JP2023531169A - Catheter system with both thermodilution and body occlusion disruption and methods for determining blood flow and performing body occlusion disruption - Google Patents

Abstract

Disclosed are catheter systems and methods for disrupting body obstructions. The catheter has proximal and distal ends and includes a catheter shaft (512) including an outer tubular member and at least one inner tubular member disposed within the outer tubular member, the inner tubular member and the outer tubular member. and at least one second lumen defined by the inner tubular member, configured to allow fluid to exit the catheter through the first fluid lumen; one or more fluid exit openings (540a, 540b) disposed in the distal end region of the catheter for directing the fluid into the first fluid lumen at a pressure range predetermined to rupture the obstruction; and fluid pressure means disposed externally of the catheter beyond its proximal end for delivering to.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation-in-part application filed in the United States on June 10, 2020 under docket no. Claim priority.

The present disclosure is directed to a catheter system that has both thermodilution and body occlusion disruption and methods for determining blood flow and performing body occlusion disruption.

Thermodilution is a method of determining blood flow through a body lumen based on an in vivo measurement of the temperature drop in blood using a temperature sensor as a result of introducing an indicator liquid (such as saline) that is cooler than the blood into the blood upstream of the temperature sensor. The measured temperature drop is a function of blood flow and set indicator fluid flow rate and can be used to determine absolute blood flow through the body lumen. Calculated absolute blood flow can be used in the diagnosis and understanding of microvascular disease.

Accordingly, there is a need to provide alternative systems and methods for determining absolute blood flow in vessels such as coronary arteries.

Furthermore, there is a need to destroy body occlusions such as thrombi, thromboses, thrombi, especially in body lumens, arteries, coronary arteries and the like.

The present disclosure is directed to several alternative designs, materials and methods of manufacturing medical device structures and assemblies and their uses.

Accordingly, one exemplary embodiment is a catheter system for determining blood flow within a body lumen. The system includes a catheter including an outer tubular member and an inner tubular member disposed within the outer tubular member. The catheter also includes a fluid lumen defined between the inner tubular member and the outer tubular member, and a second lumen (eg, guidewire lumen, temperature probe lumen, etc.) defined by the inner tubular member. One or more fluid injection openings are located in the distal end region of the catheter. The one or more fluid injection openings are configured to allow fluid to exit the catheter from the fluid lumen. Additionally, one or more fluid holes are disposed in the distal end region of the catheter and configured to allow fluid to pass from the fluid lumen to the second lumen. Optionally, the catheter system also includes an elongated member (eg, guidewire, temperature probe, etc.) advanceable through the second lumen of the catheter. The elongated member may include a temperature sensor positioned at a distal end portion of the elongated member positionable within the second lumen of the inner tubular member for measuring the temperature of fluid entering the second lumen of the inner tubular member through one or more fluid holes.

Another exemplary embodiment is a catheter system for determining blood flow within a body lumen. The system includes an elongated catheter shaft having a proximal end, a distal end and a lumen extending therethrough. The catheter shaft also includes one or more fluid injection openings located in the distal end region of the catheter shaft. The one or more fluid injection openings are configured to allow fluid to exit the lumen of the catheter shaft and enter the body cavity. A first temperature sensor is positioned within the lumen of the catheter shaft proximate to the one or more fluid injection openings. The first temperature sensor is configured to directly contact the fluid within the lumen and measure the temperature of the fluid exiting the lumen through the one or more fluid injection openings. In some cases, the elongated catheter shaft may include an elongated reduced diameter region extending distally of the one or more fluid injection openings to the distal end of the elongated catheter shaft. A second temperature sensor may be positioned outside the elongated reduced diameter region proximate the distal end of the elongated catheter shaft for measuring the mixture of blood and fluid infused into the blood from the catheter shaft.

Yet another exemplary embodiment is a method of determining blood flow within a body lumen of a patient. The method includes advancing a catheter to a desired location within the body lumen. The catheter includes an outer tubular member, an inner tubular member disposed within the outer tubular member, a fluid lumen defined between the inner and outer tubular members, and a second lumen defined by the inner tubular member. Fluid is delivered to the distal end region of the catheter through the fluid lumen. A temperature sensor attached to the elongated member is positioned within the second lumen of the catheter, and the temperature of fluid flowing from the fluid lumen to the second lumen is measured with the temperature sensor positioned within the second lumen. Fluid is infused from the fluid lumen into the blood within the body lumen, and the temperature of the fluid-blood mixture is measured with a temperature sensor attached to an elongated member positioned within the body lumen distal to the catheter. Blood flow can then be calculated based on the measured temperature of the fluid and the measured temperature of the mixture of fluid and blood.

Yet another exemplary embodiment is a catheter system for disrupting a body occlusion within a body cavity, such as a blood vessel. The term blood vessel in this specification and claims means any blood vessel through which blood flows, including blood vessels, arteries, coronary arteries, and the like. Organisms may be humans or animals. A body occlusion may be a thrombus or thrombosis, or a thrombus.

According to certain embodiments, the invention further comprises a catheter system for performing disruption of a body obstruction within a body lumen of a living organism, comprising a catheter shaft having a proximal end and a distal end, the catheter shaft having an outer tubular member, at least one inner tubular member disposed within the outer tubular member, a first fluid lumen defined between the inner tubular member and the outer tubular member, and at least one second lumen defined by the at least one inner tubular member. , to a catheter system comprising one or more fluid exit openings disposed in a distal end region of the catheter configured to allow fluid to exit the catheter from a first fluid lumen, and fluid pressure means disposed externally of the catheter beyond the proximal end for delivering said fluid into the first fluid lumen at a pressure range predetermined to disrupt said obstruction.

According to an alternative embodiment, the catheter system further comprises an elongated member advanceable through the second lumen of the catheter.

According to another feature, the elongated member includes a temperature sensor located at the distal end portion of the elongated member.

According to another variant feature, a temperature sensor at the distal end portion of the elongated member can be arranged in front of the distal end of the catheter for measuring the temperature within the blood vessel.

According to a variant embodiment, the one or more fluid exit openings extend through the wall of the outer tubular member from the inner surface of the outer tubular member to the outer surface of the outer tubular member.

According to a variant feature, the one or more fluid exit openings are configured to generate a jet of fluid exiting the catheter with sufficient pressure to cause mechanical disruption of the body occlusion.

According to a further variant feature, the one or more fluid outlet openings comprises at least a set of four fluid outlet openings equally spaced circumferentially around the outer tubular member.

According to another variant feature, the one or more fluid outlet openings comprises at least two sets of four fluid outlet openings equally spaced circumferentially around the outer tubular member.

According to another alternate embodiment, the fluid exit opening has a diameter ranging from about 50 microns (0.050 millimeters) to about 200 microns (0.200 millimeters). The diameter size selected is typically adapted to the fluid pressure, and the fluid pressure near the inlet or at least one fluid outlet opening of the catheter ranges between about 10×101,325 Pa or 10 atmospheres and about 50×101,325 Pa or 50 atmospheres.

According to a further alternative embodiment, the fluid exit opening has a diameter ranging from about 50 microns (0.050 millimeters) to about 150 microns (0.150 millimeters). The diameter size selected is typically adapted to the fluid pressure, and the fluid pressure near the inlet or at least one fluid outlet opening of the catheter ranges between about 10×101,325 Pa or 10 atmospheres and about 50×101,325 Pa or 50 atmospheres.

According to another alternate embodiment, the fluid exit opening has a diameter ranging from about 70 microns (0.070 millimeters) to about 150 microns (0.150 millimeters). The diameter size selected is typically adapted to the fluid pressure, and the fluid pressure near the inlet or at least one fluid outlet opening of the catheter ranges between about 10×101,325 Pa or 10 atmospheres and about 50×101,325 Pa or 50 atmospheres.

According to a further variant embodiment, the pressure of the fluid near the inlet or at least one fluid outlet opening of said catheter ranges between at least 30×10 1,325 Pa or 30 atmospheres and 50×10 1,325 Pa or 50 atmospheres. This pressure is particularly suitable for orifice sizes between about 70 microns (0.070 millimeters) and about 110 microns (0.110 millimeters).

According to an alternative embodiment, one or more fluid holes are located in the distal end region of the catheter and are configured to allow fluid to pass from the first fluid lumen to the second lumen, said one or more fluid holes extending through the wall of the inner tubular member from the outer surface of the inner tubular member to the inner surface of the inner tubular member.

According to a variant feature, the one or more fluid holes are one or more drainage holes configured to allow fluid to flow into the second lumen.

According to a further variant feature, the one or more fluid holes have a diameter ranging from greater than or equal to about 100 microns to about 300 microns.

According to an alternative embodiment, the elongated catheter shaft includes an elongated region of reduced diameter extending distally of the one or more fluid exit openings to the distal end of the elongated catheter shaft.

According to another alternative embodiment, a first temperature sensor is disposed within the first fluid lumen of the catheter shaft proximate to the one or more fluid exit openings, the first temperature sensor configured to directly contact the fluid in the lumen to measure the temperature of the fluid exiting the lumen through the one or more fluid exit openings.

According to another variant feature, the catheter further comprises a second temperature sensor positioned outside the elongated reduced diameter region proximate the distal end of the elongated catheter shaft.

According to a variant feature, the second temperature sensor is arranged at least 4 centimeters distal to the one or more fluid outlet openings.

According to another variant feature, the distal end of the inner tubular member is sealingly secured to the distal end of the elongated catheter shaft.

According to a further variant feature, the elongated member comprises a guidewire advanceable through the inner tubular member.

According to a variant embodiment, the guidewire comprises a temperature sensor located at the distal end portion of the guidewire to measure the temperature of the blood/fluid mixture in the body cavity distal to the one or more fluid exit openings.

According to another variant embodiment, the catheter comprises at least one pressure sensor near the at least one fluid outlet opening.

According to a further variant embodiment, the fluid is a liquid selected from saline and a blood compatible aqueous solution comprising at least one clot or thrombolytic aid.

According to another variant feature, said elongated member is a guidewire and said catheter is selected from an Over The Wire (OTW) catheter and a Single Operator Exchange (SOE) catheter.

According to a further aspect, the invention relates to a method of performing disruption of a body occlusion within a body lumen of an organism, the method comprising:
advancing the catheter to a desired location within the body lumen, the catheter comprising a catheter shaft including a proximal end and a distal end, the catheter configured to allow fluid to exit the catheter through the first fluid lumen, at least one inner tubular member disposed within the outer tubular member, a first fluid lumen defined between the inner tubular member and the outer tubular member, and at least one second lumen defined by the inner tubular member; one or more fluid exit openings located in the distal end region of the catheter;
effecting delivery of fluid through the first fluid lumen to the distal end region of the catheter at a predetermined pressure range to expel said fluid at a predetermined pressure at a pressure and duration that causes rupture of the occlusion;
including.

According to a variant embodiment, the catheter comprises at least one set of four fluid exit openings located at the distal end region of the catheter and equidistantly spaced circumferentially around the outer tubular member.

According to a further variant embodiment, the catheter comprises two sets of four fluid exit openings, located in the distal end region of the catheter and spaced equidistantly circumferentially around the outer tubular member.

According to another feature, advancing the catheter within the body step includes using an elongated member.

According to another variant feature, said elongate member is a guidewire and said catheter is selected from an over-the-wire (OTW) catheter and a single operator exchange (SOE) catheter.

According to another variant embodiment, the catheter is provided with a temperature sensor, and the method comprises using the temperature sensor to measure the temperature of the fluid exiting the catheter or of the blood in front of the distal end of the catheter.

According to a variant embodiment, the method comprises
providing at least one temperature sensor at the distal end of the elongated member and positioning the elongated member at a location distal to the catheter to measure the temperature of the fluid-blood mixture distal to the catheter;
further includes

According to another alternative embodiment, the catheter includes one or more fluid holes located in a distal end region of the catheter near at least one said fluid exit opening, the one or more fluid holes configured on the inner tube to allow fluid to flow from a first fluid lumen to a second lumen, and the method further comprising repositioning the elongated member at a position in front of said fluid holes for measuring the temperature of the fluid near the fluid exiting the catheter.

According to another alternate embodiment, the fluid exit opening has a diameter ranging from about 50 microns (0.050 millimeters) to about 200 microns (0.200 millimeters). The diameter size selected is typically adapted to the fluid pressure, and the fluid pressure near the inlet or at least one fluid outlet opening of the catheter ranges between about 10×101,325 Pa or 10 atmospheres and about 50×101,325 Pa or 50 atmospheres.

According to alternative embodiments, the fluid exit opening has a diameter in the range of about 50 microns (0.050 millimeters) to about 150 microns (0.150 millimeters).

According to further alternative embodiments, the fluid exit opening has a diameter ranging from about 70 microns (0.070 millimeters) to about 150 microns (0.150 millimeters) or about 110 microns (0.110 millimeters).

According to a further variant embodiment, the pressure of the fluid near the inlet or at least one fluid outlet opening of said catheter is at least 20×10,325 Pa or 20 atmospheres, or even in the range between 30×10,325 Pa, or 30 atmospheres and 50×10,325 Pa, or 50 atmospheres, or more. This pressure is particularly suitable for orifice sizes ranging from about 50 microns (0.050 millimeters) to about 200 microns (0.200 millimeters).

The time required to completely or substantially completely destroy the obstruction will, of course, depend on the type and amount of obstruction. Said time generally varies from a few seconds to several minutes, especially from about 30 seconds to about 5 minutes.

According to another variant embodiment, the catheter comprises at least one pressure sensor in the vicinity of the at least one fluid exit opening and the method comprises measuring pressure in the vicinity of said fluid exit opening and correcting the pressure value of the fluid injected into said fluid lumen.

The above summary of several example embodiments is not intended to describe each disclosed embodiment or every implementation of the disclosed aspects.

Aspects of the present disclosure can be more fully understood by considering the following detailed description of various embodiments in conjunction with the accompanying drawings.

1 is a schematic diagram of an exemplary catheter system including an infusion catheter and associated guidewire for determining blood flow through a body lumen using thermodilution techniques; FIG. 1A is a cross-sectional view along line 1A-1A of FIG. 1; FIG. 2 is a side view of a portion of the infusion catheter of FIG. 1; FIG. FIG. 4 is a schematic diagram of an alternative embodiment of a catheter system including an infusion catheter and associated guidewire for determining blood flow through a body lumen using thermodilution techniques; FIG. 2 illustrates aspects of an exemplary method for determining blood flow through a body lumen using the catheter system of FIG. 1; FIG. 2 illustrates aspects of an exemplary method for determining blood flow through a body lumen using the catheter system of FIG. 1; FIG. 2 illustrates aspects of an exemplary method for determining blood flow through a body lumen using the catheter system of FIG. 1; FIG. 2 illustrates aspects of an exemplary method for determining blood flow through a body lumen using the catheter system of FIG. 1; FIG. 4 is a schematic diagram of another embodiment of a catheter system for determining blood flow through a body lumen using thermodilution techniques; FIG. 4 is a schematic diagram of another embodiment of a catheter system for determining blood flow through a body lumen using thermodilution techniques; FIG. 4 is a schematic diagram of another embodiment of a catheter system for determining blood flow through a body lumen using thermodilution techniques; 1 is a schematic diagram of an exemplary additional catheter system including a catheter and associated guidewire for the disruption of a body occlusion, such as a thrombus, through a body lumen of a living body (either human or animal); FIG. 1A is a cross-sectional view along line 1A-1A of FIG. 1 showing four equally circumferentially spaced sets of fluid exit openings; FIG. 12 is a side view of a portion of the catheter of FIG. 11 with a modified feature having four fluid exit openings in a square; FIG. 1 is a schematic diagram of an alternative embodiment of a catheter system including a catheter and associated guidewire for effecting disruption of a bodily obstruction through a bodily lumen of a human or animal organism; FIG. 12A-12C illustrate aspects of an exemplary method for performing disruption of a body obstruction through a body lumen using the catheter system of FIG. 11; 12A-12C illustrate aspects of an exemplary method for performing disruption of a body obstruction through a body lumen using the catheter system of FIG. 11; 12A-12C illustrate aspects of an exemplary method for performing disruption of a body obstruction through a body lumen using the catheter system of FIG. 11; 12A-12C illustrate aspects of an exemplary method for performing disruption of a body obstruction through a body lumen using the catheter system of FIG. 11; 1 is a schematic diagram of another embodiment of a catheter system for performing disruption of a body occlusion, such as a thrombus, through a bodily lumen of a living body (either human or animal); FIG. 1 is a schematic diagram of another embodiment of a catheter system for disrupting a body obstruction, such as a thrombus, through a bodily lumen of a living organism (either human or animal); FIG. FIG. 2 is a schematic diagram of another embodiment of a catheter system for performing disruption of a body obstruction, such as a thrombus, through a body lumen of an organism, human or animal;

While the aspects of the disclosure are susceptible to various modifications and alternative forms, details thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the disclosed aspects to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure.

For the defined terms below, these definitions shall apply unless a different definition is provided in the claims or elsewhere in this specification.

All numerical values are assumed herein to be modified by the term "about," whether or not explicitly indicated. The term "about" generally refers to a range of numbers that one skilled in the art would consider equivalent to the recited value (ie, having the same function or result). In many cases, the term "about" can indicate including numbers rounded to the nearest significant figure.

The recitation of numerical ranges by endpoints includes all numbers within that range (eg 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

Although some suitable dimensions, ranges and/or values have been disclosed relating to various components, functions and/or specifications, those skilled in the art, inspired by this disclosure, will appreciate that the desired dimensions, ranges and/or values may depart from those explicitly disclosed.

As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.

A body lumen should be understood to mean any blood vessel in a living body through which blood flows, including blood vessels, arteries, coronary arteries, and the like. Living things can be humans or animals. A body or vessel occlusion can be any occlusion, such as, but not limited to, a thrombus, thrombosis, or blood clot.

The following detailed description should be read with reference to the drawings in which like elements in different drawings are numbered the same. The detailed description and drawings, which are not necessarily to scale, depict exemplary embodiments and are not intended to limit the scope of the disclosure. The illustrated exemplary embodiments are intended as examples only. Selected features of any exemplary embodiment may be incorporated into additional embodiments unless expressly stated to the contrary.

An exemplary catheter system 2 including an infusion catheter 10 and associated guidewire 30 for determining blood flow through a body lumen using thermodilution techniques is shown in FIG. Infusion catheter 10 may include an elongated catheter shaft 12 extending distally from hub assembly 20 . Catheter shaft 12 may have a proximal end 16 attached to hub assembly 20 and a distal end 18 opposite proximal end 16 . The catheter shaft 12 may be a dual lumen catheter shaft having a first infusion fluid lumen 34 and a second guidewire lumen 36 extending along at least a portion of the catheter shaft 12 and configured to advance the infusion catheter 10 over the guidewire 30. For example, in some embodiments, catheter 10 may be an over-the-wire (OTW) catheter in which guidewire lumen 36 may extend the entire length of catheter shaft 12 from distal end 18 to proximal end 16 . However, in other embodiments, such as the embodiment shown in FIG. 1, catheter 10 may be a single operator exchange (SOE) catheter in which guidewire lumen 36 extends only through a distal portion of catheter shaft 12.

Catheter shaft 12 may include an outer tubular member 13 and an inner tubular member 14 extending through the lumen of outer tubular member 13 . In the SOE catheter construction of FIG. 1, infusion fluid lumen 34 may be defined by outer tubular member 13 passing through the proximal portion of catheter shaft 12 . Infusion fluid lumen 34 , on the other hand, may be defined through the distal portion of catheter shaft 12 and between the outer surface of inner tubular member 14 and the inner surface of outer tubular member 13 . In embodiments where the catheter is of OTW construction, an infusion fluid lumen 34 may be defined throughout catheter shaft 12 between the outer surface of inner tubular member 14 and the inner surface of outer tubular member 13 . Hub assembly 20 may include proximal port 22 in fluid communication with infusion fluid lumen 34 . An infusion source (not shown), such as an infusion pump, syringe, or the like, may be coupled to proximal port 22 to supply infusion lumen 34 with infusion fluid.

The lumen of the inner tubular member 14 may define a guidewire lumen 36 having a distal guidewire port 28 proximate the distal end of the inner tubular member 14 and a proximal guidewire port 26 proximate the proximal end of the inner tubular member 14. A distal guidewire port 28 may be located proximate the distal end 18 of the catheter shaft 12, and a proximal guidewire port 26 may be located a short distance proximal to the distal end 18 of the catheter shaft 12 and distal to the proximal end 16. Proximal guidewire port 26 may be of any desired structure that provides access to guidewire lumen 36 . For example, in some embodiments, proximal guidewire port 26 may be formed according to a guidewire port forming process such as that described in US Pat. No. 6,409,863, incorporated herein by reference.

The distal end portion 38 of the outer tubular member 13 may be a reduced diameter portion or neck portion secured to the inner tubular member 14 to seal the infusion lumen 34 adjacent the distal end 18 of the catheter shaft 12. For example, distal end portion 38 may include a tapered region where outer tubular member 13 tapers to a reduced inner and/or outer diameter at the distal end of outer tubular member 13 . Thus, the inner surface of the distal end portion of outer tubular member 13 may be secured to the outer surface of the distal end portion of inner tubular member 14 at distal end portion 38 . Outer tubular member 13 may be secured to inner tubular member 14 by, for example, laser welding, hot jaws, or other thermal bonding, adhesive bonding, or other bonding as appropriate.

In some cases, catheter shaft 12 may include a distal tip 24 formed as a separate component and secured to distal end 18 of catheter shaft 12 . For example, in some cases, distal tip 24 may be secured to inner tubular member 14 and/or outer tubular member 13 by, for example, laser welding, hot jaws, or other thermal bonding, adhesive bonding, or other bonding as appropriate. As shown in FIG. 1, in some embodiments, the distal end portion of outer tubular member 13 may span the junction between inner tubular member 14 and distal tip 24 such that the distal end portion of outer tubular member 13 is joined to inner tubular member 14 and distal tip 24, respectively. In other examples, distal tip 24 may be formed as an integral part of inner tubular member 14 and/or outer tubular member 13 .

Catheter shaft 12 may also include one or more radiopaque markers 52 positioned proximate distal end 18 of catheter shaft 12 . Radiopaque markers 52 may facilitate viewing the position of distal end 18 of catheter shaft 12 using fluoroscopic or other visualization techniques during a medical procedure. In the exemplary embodiment, catheter shaft 12 includes a radiopaque marker 52 secured to inner tubular member 14 proximate tapered distal end portion 38 of catheter shaft 12 .

Catheter shaft 12 may include one or more fluid injection openings 40 (eg, holes, openings) located at the distal end region of catheter 10 . Fluid injection opening 40 may be in fluid communication with injection fluid lumen 34 and may be configured to allow injection fluid to exit catheter 10 from injection fluid lumen 34 proximate distal end 18 of catheter shaft 12 . For example, catheter shaft 12 may include a plurality of fluid injection openings 40 extending through the wall of outer tubular member 13 from the inner surface of outer tubular member 13 to the outer surface of outer tubular member 13 . As shown in FIG. 1A, in one exemplary embodiment, the catheter shaft 12 can include four fluid injection openings 40 evenly spaced circumferentially around the outer tubular member 13 (i.e., each fluid injection opening 40 is positioned approximately 90° from another fluid injection opening 40). In other embodiments, catheter shaft 12 may include one, two, three, or more fluid injection openings 40 disposed about catheter shaft 12 .

Fluid injection openings 40 may be configured to emit an injection fluid (e.g., indicator fluid) radially outwardly from each of fluid injection openings 40 to facilitate mixing of the injection fluid with blood flowing through the vessel lumen. In other embodiments, fluid injection openings 40 may be oriented differently to allow injection fluid to exit catheter shaft 12 in a generally distal direction, if desired.

As shown in FIG. 2, in some cases one or more of the fluid injection openings 40 may be longitudinally displaced from one or more of the other fluid injection openings 40 . For example, in some embodiments, oppositely positioned first and second fluid injection openings 40a (only one of which is shown in FIG. 2) may be positioned a longitudinal distance X, such as about 0.5 millimeters, about 1 millimeter, about 2 millimeters, or about 3 millimeters away from oppositely positioned third and fourth fluid injection openings 40b. In other embodiments, the oppositely positioned first and second fluid injection openings 40a can be longitudinally aligned with the oppositely positioned third and fourth fluid injection openings 40b, if desired.

One or more fluid injection openings 40 may be configured to produce a jet of injection fluid F that exits catheter shaft 12 . For example, the fluid injection openings 40 may be appropriately sized to create a pressure flow of injection fluid F exiting the fluid injection openings 40 . In some cases, the fluid injection opening 40 is about 25 microns (0.025 millimeters) to about 300 microns (0.300 millimeters), about 25 microns (0.025 millimeters) to about 100 microns (0.100 millimeters), about 100 microns (0.100 millimeters) to about 200 microns (0.200 millimeters), or about 200 microns (0.200 millimeters) to about 300 microns (0.300 millimeters). ). The size of the fluid injection opening 40 can be selected based on the amount of injection fluid to ensure that a jet of injection fluid exiting the catheter shaft 12 is formed.

Catheter shaft 12 may also include one or more fluid holes 50 (eg, openings, apertures) located in the distal end region of catheter 10 . The fluid bore may be in fluid communication with the infusion fluid lumen 34 and may be configured to allow infusion fluid to pass from the infusion fluid lumen 34 to the guidewire lumen 36 . For example, catheter shaft 12 may include one or more fluid holes 50 extending through the wall of inner tubular member 14 from the outer surface of inner tubular member 14 to the inner surface of inner tubular member 14 . As shown in FIG. 1A, in an exemplary embodiment, catheter shaft 12 may include one fluid hole 50 extending through the wall of inner tubular member 14 to allow infusion fluid F to enter guidewire lumen 36 from infusion fluid lumen 34. However, in other embodiments, catheter shaft 12 may include two, three, or more such fluid holes 50 as desired.

Fluid hole 50 may be a weep hole configured to allow infusion fluid to slowly seep or exude from infusion fluid lumen 34 into guidewire lumen 36 . For example, fluid port 50 may be configured to allow infusion fluid to seep, drip, dribble, ooze, or otherwise slowly seep into guidewire lumen 36 . In some cases, fluid hole 50 may have a diameter of, for example, about 100 microns (0.100 millimeters) to about 300 microns (0.300 millimeters), about 100 microns (0.100 millimeters) to about 200 microns (0.200 millimeters), or about 200 microns (0.200 millimeters) to about 300 microns (0.300 millimeters).

Catheter system 2 may also include an elongated member such as guidewire 30 sized and configured to be disposed through guidewire lumen 36 of infusion catheter 10 so that infusion catheter 10 may be advanced along guidewire 30 to a target location in the vasculature. Guidewire 30 may include a temperature sensor 32 , such as a thermistor or thermocouple, attached to the distal end region of guidewire 30 . An exemplary embodiment of guidewire 30 with attached temperature sensor 32 is described in US Pat. No. 6,343,514, incorporated herein by reference. Optionally, guidewire 30 may also include a pressure sensor positioned at the distal end region of guidewire 30 for measuring blood pressure at a target location within the vasculature.

Another exemplary catheter system 102 including an infusion catheter 110 and associated guidewire 30 for determining blood flow through a body lumen using thermodilution techniques is shown in FIG. In many respects, injection catheter 110 can be similar to injection catheter 10 shown in FIG. For example, the infusion catheter 110 can include an elongate catheter shaft 12 extending distally from the hub assembly 20 having a proximal end 16 attached to the hub assembly 20 and a distal end 18 opposite the proximal end 16. Catheter shaft 12 may be a dual lumen catheter shaft having a first infusion fluid lumen 34 and a second guidewire lumen 36 extending along at least a portion of catheter shaft 12 configured to advance an infusion catheter 110 over guidewire 30.

Catheter shaft 12 may include an outer tubular member 13 and an inner tubular member 14 extending through the lumen of outer tubular member 13 . In the SOE catheter construction of FIG. 3, infusion fluid lumen 34 may be defined by outer tubular member 13 passing through the proximal portion of catheter shaft 12 . Infusion fluid lumen 34 , on the other hand, may be defined through the distal portion of catheter shaft 12 and between the outer surface of inner tubular member 14 and the inner surface of outer tubular member 13 . In embodiments where the catheter is of OTW construction, an infusion fluid lumen 34 may be defined throughout catheter shaft 12 between the outer surface of inner tubular member 14 and the inner surface of outer tubular member 13 . Hub assembly 20 may include proximal port 22 in fluid communication with infusion fluid lumen 34 . An infusion source (not shown), such as an infusion pump, syringe, or the like, may be coupled to proximal port 22 to supply infusion lumen 34 with infusion fluid.

The lumen of the inner tubular member 14 may define a guidewire lumen 36 having a distal guidewire port 28 proximate the distal end of the inner tubular member 14 and a proximal guidewire port 26 proximate the proximal end of the inner tubular member 14.

Catheter 110 may include an inflatable balloon 120 attached to a distal region of catheter shaft 12 . For example, inflatable balloon 120 may include a proximal balloon waist secured (e.g., heat or adhesively bonded) to the distal end of outer tubular member 13 and a distal balloon waist secured (e.g., heat or adhesively bonded) to the distal end of inner tubular member 14. An infusion fluid lumen 34 extending along catheter shaft 12 can be in fluid communication with the interior of inflatable balloon 120 to deliver infusion fluid to inflatable balloon 120 .

Inflatable balloon 120 may include one or more fluid injection openings 140 (eg, holes, openings) configured to allow infusion fluid to exit balloon 120 from infusion fluid lumen 34 . For example, balloon 120 may include a plurality of fluid injection openings 140 that extend through the wall of balloon 120 when balloon 120 is inflated with an injection fluid. In one exemplary embodiment, the balloon 120 may include four fluid injection openings 140 equally spaced around the circumference of the balloon 120 (i.e., each fluid injection opening 140 is positioned approximately 90° from another fluid injection opening 140). In other embodiments, balloon 120 may include one, two, three, or more fluid injection openings 140 positioned around balloon 120 .

Fluid injection openings 140 may be configured to expel injection fluid radially outward from balloon 120 to facilitate mixing of the injection fluid with blood flowing through the vessel lumen. For example, fluid injection openings 140 can be located in the distal cone portion of balloon 120, the cylindrical body portion of balloon 120, or at a different location, as desired. In some cases, the balloon may be configured to create turbulence in blood flow to facilitate mixing of the infusion fluid with blood flowing distal to balloon 120 .

Fluid injection openings 140 may be configured to produce a jet of injection fluid that exits balloon 120 . For example, the fluid injection openings 140 can be appropriately sized to create a pressure flow of injection fluid exiting the fluid injection openings 140 . The size of fluid injection opening 140 can be selected based on the volume of injection fluid to ensure that a jet of injection fluid forms and exits balloon 120 .

Similar to the infusion catheter 10, the catheter shaft 12 of the infusion catheter 110 may also include one or more fluid holes 50 (e.g., openings, openings) located in the distal end region of the catheter 110 and configured to allow infusion fluid to pass from the infusion fluid lumen 34 to the guidewire lumen 36. For example, catheter shaft 12 may include one or more fluid holes 50 extending through the wall of inner tubular member 14 from the outer surface of inner tubular member 14 to the inner surface of inner tubular member 14 . Fluid hole 50 may be a weep hole configured to allow infusion fluid to slowly seep or exude from infusion fluid lumen 34 into guidewire lumen 36 . For example, fluid port 50 may be configured to allow infusion fluid to seep, drip, dribble, ooze, or otherwise slowly seep into guidewire lumen 36 .

4-7 illustrate aspects of an exemplary method for determining blood flow through a body lumen using the catheter system of FIG. As shown in FIG. 4, a guidewire, such as a guidewire 30 having a temperature sensor 32 attached to its distal end region, can be advanced through a lumen 82 of a vessel 80 of the vasculature to a desired target location, such as a coronary artery.

Infusion catheter 10 can then be advanced over guidewire 30 to a target location within blood vessel 80, as shown in FIG. In other embodiments, the infusion catheter 10 can be advanced over a different guidewire, such as a conventional guidewire, to the target location, after which the guidewire can be replaced with a guidewire 30 with a temperature sensor 32 attached.

With a temperature sensor 32 located distal to the injection catheter 10, the actual temperature _Tb of the blood can be measured by the temperature sensor 32 and recorded. In another example, an estimated temperature (eg, 98.6° F.) may be used as the blood temperature _Tb for subsequent calculations.

As shown in FIG. 6, the guidewire 30 can be withdrawn proximally to reposition the sensor 32 within the guidewire lumen 36 . For example, sensor 32 may be positioned within guidewire lumen 36 adjacent fluid bore 50 extending through inner tubular member 14 . Infusion fluid F (eg, saline) may be delivered to the distal end region of catheter 10 through infusion fluid lumen 34 . For example, infusion fluid F may be provided to the distal region of catheter 10 at a pressure of about 1 atmosphere to about 30 atmospheres. A small amount of infusion fluid F can enter guidewire lumen 36 from infusion fluid lumen 34 through fluid hole 50 . Thus, with the temperature sensor 32 positioned within the guidewire lumen 36, the actual temperature T _f of the infusion fluid F at the distal end region of the catheter 10 can be measured and recorded. For example, temperature sensor 32 may be positioned adjacent fluid bore 50 such that infusion fluid F passing within guidewire lumen 36 is in direct contact with temperature sensor 32 within guidewire lumen 36 . In other examples, the temperature sensor 32 can be otherwise positioned within the guidewire lumen 36 such that the infusion fluid F located within the guidewire lumen 36 is in direct contact with the temperature sensor 32 within the guidewire lumen 36.

A temperature sensor 32 on the guidewire 30 can then be advanced to a position distal to the catheter 10, as shown in FIG. For example, temperature sensor 32 may be advanced distally to a position located a distance D from fluid injection opening 40 . In some cases, the distance D may be about 3 centimeters or more, about 4 centimeters or more, about 5 centimeters or more, or about 6 centimeters or more to ensure that the infusion fluid F is thoroughly mixed with the blood before reaching the temperature sensor 32. For example, the temperature sensor 32 can be positioned at a distance D of about 3 cm to about 8 cm, about 3 cm to about 6 cm, about 4 cm to about 8 cm, or about 4 cm to about 6 cm distal to the infusion fluid opening 40 on the catheter shaft 12.

Infusion fluid F may be injected from infusion fluid lumen 34 through fluid infusion opening 40 into the blood stream within lumen 82 of blood vessel 80 . For example, a continuous flow of infusion fluid F at a known flow rate through infusion fluid lumen 34 may be provided by an infusion pump, with a substantial portion of infusion fluid F exiting catheter 10 through infusion lumen 40 and a small amount of infusion fluid F exiting catheter 10 through guidewire lumen 36. The flow rate of infusion F may be set at any desired flow rate, eg, a continuous flow rate of about 15 ml/min, about 20 ml/min, about 25 ml/min, about 30 ml/min, about 35 ml/min, or about 40 ml/min. Infusion fluid F may mix with blood flowing through vessel 80 to provide a mixture of blood and infusion fluid F. FIG. If the temperature T _f (eg, room temperature) of the infusion fluid F is lower than the temperature T _b of the blood, the mixture of the blood and the infusion fluid F may have a temperature T _m that is lower than the temperature T _b of the blood.

With the temperature sensor 32 positioned at a distance D distal to the infusion fluid opening 40, the temperature T _m of the mixture of blood and infusion fluid F can be measured with the temperature sensor 32 and recorded.

Multiple temperature measurements of the infusate, blood, and/or mixture of blood and infusate may be obtained to calculate an average or adjusted temperature for calculating blood flow through vessel 80 .

Note that in some cases the temperatures can be measured in any order. For _example , the temperature _Tm of the mixture of infusate fluid and blood may first be measured with a temperature sensor 32 positioned a distance D distal of the catheter 10, as shown in FIG.

Although a single temperature sensor 32 is shown to measure the temperature T _f of the fluid F, the temperature T _b of the blood, and the temperature T _m of the mixture of blood and infusate fluid, in some cases, the temperature of the fluid F, T _f , the temperature T _b of the blood, and/or the temperature T _m of the mixture of the blood and infusate fluid are different temperature sensors positioned on the guide wire 30 separate from the temperature sensor 32, positioned on the second guide wire, positioned on the catheter 10 . can be measured using a temperature sensor located on or positioned to take the corresponding temperature.

Note that the patient is usually hyperemic before temperature measurements are taken. The measured temperature can then be used to calculate the actual absolute blood flow of blood in vessel 80 at the target location. For example, blood flow based on the measured blood temperature _Tb and the measured fluid-blood mixture temperature _Tm can be calculated using the following equations.
Q _b = Q _f × (T _f - T _b )/(T _m - T _b )
where Q _b = actual blood flow
Q _f = flow rate of infusion
T _f = temperature of infusion
T _b = blood temperature
T _m = temperature of the mixture of blood and fluid.

Therefore, the actual absolute flow rate of blood through vessel 80 at the target location can be calculated. Absolute blood flow can be used in diagnostic assessments to determine patient disease status. Additionally, the calculated absolute blood flow can be combined with other measurements to provide further diagnostic analysis. For example, the calculated absolute blood flow can be combined with the absolute blood pressure measured at the target location of vessel 80 to determine the absolute resistance of vessel 80 .

In some cases, fractional flow reserve (FFR) can be used to measure the pressure drop across a stenosis or narrowing of vessel 80 . Fractional flow reserve (FFR) can be calculated by the following formula.
FFR= _Pd / _Pp
where P _d = pressure measured distal to the stenosis
P _p =pressure measured proximal to the stenosis.

Based on the pressure measured proximal and distal to the stenosis or stenosis and the absolute flow of blood through the vessel proximate to the stenosis or stenosis, the FFR can be calculated and the normal maximum flow through the vessel can be calculated using the following formula:
FFR= _Qb / _Qn
where Q _b = actual blood flow
Q _n = normal maximum flow rate.

If the blood flow rate is calculated and the pressures proximal and distal to the stenosis are calculated, the stenosis or stenotic resistance of vessel 80 can be calculated by the following equation.
R _s = (P _p −P _d )/Q _b
where R _s = resistance across the constriction or constriction
P _d = pressure measured distal to the stenosis or narrowing
P _p = pressure measured proximal to the stenosis or narrowing
Q _b = actual blood flow.

Therefore, measured actual blood flow, like other calculated parameters, is useful in diagnosing and understanding many pathophysiological conditions such as heart transplantation, stem cell therapy, or transmural myocardial infarction.

Another embodiment of a catheter system 202 for determining blood flow through a body lumen using thermodilution techniques is shown in FIG. Catheter system 202 may include an infusion catheter 210 and possibly an associated guidewire 30 . Infusion catheter 210 may include an elongated catheter shaft 212 extending distally from hub assembly 220 . Catheter shaft 212 may have a proximal end 216 attached to hub assembly 220 and a distal end 218 opposite proximal end 216 . Catheter shaft 212 may be a single lumen catheter shaft formed from a tubular member 213 having an infusion fluid lumen 234 defined therein.

Catheter shaft 212 may include a reduced diameter distal end region 224 that extends to distal end 218 of catheter shaft 212 . Guidewire 230 may extend through infusion fluid lumen 234 of catheter shaft 212 from a proximal guidewire port 226 located within hub assembly 220 to a distal guidewire port 228 at the distal tip of reduced diameter distal end region 224 . The inner diameter of the reduced diameter distal end region 224 can be sized to approximate the diameter of the guidewire 230 to substantially prevent leakage of infusion fluid from the catheter shaft 212 through the distal guidewire port 228 . The reduced diameter distal end region 224 can have a length L of, for example, about 3 centimeters to about 6 centimeters.

Hub assembly 220 may also include proximal fluid port 222 in fluid communication with infusion fluid lumen 234 . An infusion fluid source (not shown) such as an infusion pump, syringe, or the like, can be coupled to proximal fluid port 222 to supply infusion fluid F to infusion fluid lumen 234 .

Catheter shaft 212 may include one or more fluid injection openings 240 (eg, holes, openings) located at the distal end region of catheter 210 .
Fluid injection opening 240 may be in fluid communication with injection fluid lumen 234 and may be configured to allow injection fluid to exit catheter 210 from injection fluid lumen 234 proximate distal end 218 of catheter shaft 212 . For example, catheter shaft 212 can include a plurality of fluid injection openings 240 extending through the wall of tubular member 213 from the inner surface of tubular member 213 to the outer surface of tubular member 213 . Injection opening 240 may be of similar construction and arrangement as injection opening 40 of catheter 10 described above.

Fluid injection openings 240 may be configured to emit injection fluid radially outwardly from each of fluid injection openings 240 to facilitate mixing of the injection fluid with blood flowing through the vessel lumen. In other embodiments, fluid injection openings 240 can be oriented differently to allow injection fluid to exit generally distally from catheter shaft 212, if desired.

Infusion catheter 210 may include a first temperature sensor 260 , such as a thermistor or thermocouple, positioned within infusion fluid lumen 234 of catheter shaft 212 proximate fluid infusion opening 240 . The temperature sensor 260 may be configured to directly contact the infusion fluid F within the infusion fluid lumen 234 to measure the temperature T _f of the infusion fluid F exiting the infusion fluid lumen 234 through the fluid infusion opening 240 .

The infusion catheter 210 may also include a second temperature sensor 232 , such as a thermistor or thermocouple, located outside the elongated, reduced diameter distal end region 224 proximate the distal end 218 of the catheter shaft 212 . A second temperature sensor 232 may be positioned a distance D distal of one or more fluid injection openings 240 . A second temperature sensor 232 mounted on the exterior of the catheter shaft 212 may be used to measure the temperature T _b of the blood flowing within the lumen 82 of the vessel 80 and the temperature T _m of the mixture of blood and infusion fluid flowing distal to the infusion fluid opening 240. In some cases, the distance D may be about 3 centimeters or more, about 4 centimeters or more, about 5 centimeters or more, or about 6 centimeters or more to ensure that the infusion fluid F is thoroughly mixed with the blood before reaching the temperature sensor 232. For example, the temperature sensor 232 can be positioned at a distance D of about 3 cm to about 8 cm, about 3 cm to about 6 cm, about 4 cm to about 8 cm, or about 4 cm to about 6 cm distal to the infusion fluid opening 240 on the catheter shaft 212.

The measured temperature obtained at the infusion catheter 210 can then be used to calculate the actual absolute blood flow of blood within the vessel 80 at the target location, as well as other calculated parameters that can aid in the diagnosis and understanding of many pathophysiological conditions.

Another embodiment of a catheter system 302 for determining blood flow through a body lumen using thermodilution techniques is shown in FIG. Catheter system 302 may include an infusion catheter 310 and possibly an associated guidewire 330 . Infusion catheter 310 may include an elongated catheter shaft 312 extending distally from hub assembly 320 . Catheter shaft 312 may have a proximal end 316 attached to hub assembly 320 and a distal end 318 opposite proximal end 316 . Catheter shaft 312 may be a dual lumen catheter shaft having an infusion fluid lumen 334 and a guidewire lumen 336 extending through catheter shaft 212 configured to advance infusion catheter 310 over guidewire 330 . As shown in FIG. 9, catheter 310 may be an over-the-wire (OTW) catheter in which guidewire lumen 336 may extend the entire length of catheter shaft 312 from a proximal guidewire port 326 located in hub assembly 320 to a distal guidewire port 328 at distal end 218 of catheter shaft 312. However, in other embodiments, catheter 310 may be a single operator exchange (SOE) catheter in which guidewire lumen 336 extends only through a distal portion of catheter shaft 312 .

Catheter shaft 312 may include an outer tubular member 313 and an inner tubular member 314 extending through the lumen of outer tubular member 313 . In some cases, outer tubular member 313 can coaxially surround inner tubular member 314 . A lumen of inner tubular member 314 may define a guidewire lumen 336 . Infusion fluid lumen 334 may be defined between the outer surface of inner tubular member 314 and the inner surface of outer tubular member 313 . Hub assembly 320 may include proximal port 322 in fluid communication with infusion fluid lumen 334 . An infusion source (not shown), such as an infusion pump, syringe, or the like, can be coupled to proximal port 322 to supply infusion fluid lumen 334 with infusion fluid.

The distal end portion 338 of the outer tubular member 313 may be a reduced diameter portion or neck portion secured to the inner tubular member 314 to seal the infusion fluid lumen 334 proximate the distal end 318 of the catheter shaft 312 . For example, distal end portion 338 can include a tapered region where outer tubular member 313 tapers to a reduced inner and/or outer diameter at the distal end of outer tubular member 313 . Thus, the inner surface of the distal end portion of outer tubular member 313 may be secured to the outer surface of the distal end portion of inner tubular member 314 of distal end portion 38 . Outer tubular member 313 may be secured to inner tubular member 314 by, for example, laser welding, hot jaws, or other thermal bonding, adhesive bonding, or other bonding as appropriate.

In some cases, the catheter shaft 312 can include a distal tip that is formed as a separate component and fixed to the distal end 318 of the catheter shaft 312 or that can be formed as an integral part of the inner tubular member 314 and/or the outer tubular member 313.

Catheter shaft 312 may include one or more fluid injection openings 340 (eg, holes, openings) located at the distal end region of catheter 310 . Fluid injection opening 340 may be in fluid communication with injection fluid lumen 334 and may be configured to allow injection fluid to exit catheter 310 from injection fluid lumen 334 proximate distal end 318 of catheter shaft 312 . For example, catheter shaft 312 can include a plurality of fluid injection openings 340 extending through the wall of outer tubular member 313 from the inner surface of outer tubular member 313 to the outer surface of outer tubular member 313 . Infusion fluid opening 340 may be of similar construction and arrangement as infusion opening 40 of catheter 10 described above.

Fluid injection openings 340 may be configured to expel infusion fluid F in a radially outward direction from each of fluid injection openings 340 to facilitate mixing of infusion fluid F with blood flowing through the vessel lumen. In other embodiments, fluid injection openings 340 may be oriented differently in a manner that allows injection fluid to exit catheter shaft 312 in a generally distal direction, if desired.

Infusion catheter 310 may include a temperature sensor 360 , such as a thermistor or thermocouple, positioned within infusion fluid lumen 334 of catheter shaft 312 proximate fluid infusion opening 340 . For example, temperature sensor 360 may be secured to the inner surface of outer tubular member 313 proximate one of fluid injection openings 340 . The temperature sensor 360 may be configured to directly contact the infusion fluid F within the infusion fluid lumen 334 to measure the temperature T _f of the infusion fluid F exiting the infusion fluid lumen 334 through the fluid infusion opening 340 .

The catheter system 302 can also include a guidewire 330 sized and configured to be disposed through a guidewire lumen 336 of the infusion catheter 310 so that the infusion catheter 310 can be advanced along the guidewire 330 to a target location in the vascular system. Guidewire 330 may include a temperature sensor 332 , such as a thermistor or thermocouple, attached to the distal end region of guidewire 330 . An exemplary embodiment of guidewire 330 with attached temperature sensor 332 is described in US Pat. No. 6,343,514, incorporated herein by reference. Optionally, guidewire 330 may also include a pressure sensor positioned at the distal end region of guidewire 330 to measure blood pressure at a target location within the vasculature. A temperature sensor 332 attached to the guidewire 330 can be used to measure the temperature T _b of the blood flowing within the lumen 82 of the vessel 80 and the temperature T _m of the mixture of blood and infusion fluid flowing distal to the infusion fluid opening 340 . The temperature sensor 332 may be positioned a distance D distal from the infusion opening 340 when taking temperature measurements of the blood and infusion mixture. In some cases, distance D may be about 3 centimeters or more, about 4 centimeters or more, about 5 centimeters or more, or about 6 centimeters or more to ensure that infusion fluid F is thoroughly mixed with blood before reaching temperature sensor 332. For example, the temperature sensor 332 can be positioned at a distance D of about 3 cm to about 8 cm, about 3 cm to about 6 cm, about 4 cm to about 8 cm, or about 4 cm to about 6 cm distal to the infusion fluid opening 340 on the catheter shaft 312.

The measured temperatures obtained with the infusion catheter 310 and guidewire 330 can then be used to calculate the actual absolute blood flow of blood in the vessel 80 at the target location, as well as other calculated parameters that can aid in the diagnosis and understanding of many pathophysiological conditions.

Another embodiment of a catheter system 402 for determining blood flow through a body lumen using thermodilution techniques is shown in FIG. Catheter system 402 may include an injection catheter 410 and possibly an associated temperature probe 470 and/or guidewire 430 . In many respects, injection catheter 410 can be similar to injection catheter 10 shown in FIG. For example, infusion catheter 410 may include an elongated catheter shaft 412 extending distally from hub assembly 420 having a proximal end 416 attached to hub assembly 420 and a distal end 418 opposite proximal end 416 . Catheter shaft 412 may be a triple lumen catheter shaft having a first infusion fluid lumen 434, a second auxiliary lumen 435 (e.g., a temperature probe lumen), and a third guidewire lumen 436 extending along at least a portion of catheter shaft 412 and configured to advance infusion catheter 410 over guidewire 430.

Catheter shaft 412 may include an outer tubular member 413 and first and second inner tubular members 415 , 414 extending through lumens of outer tubular member 413 . Infusion fluid lumen 434 may be defined by a portion of the lumen of outer tubular member 413 outside first and second inner tubular members 415,414. Hub assembly 420 may include proximal port 422 in fluid communication with infusion fluid lumen 434 . An infusion source (not shown), such as an infusion pump, syringe, or the like, can be coupled to proximal port 422 to supply infusion lumen 434 with infusion fluid. In other embodiments, catheter shaft 412 may be an extruded tubular member including, for example, three lumens extending therethrough.

The lumen of the second inner tubular member 414 may define a guidewire lumen 436 having a distal guidewire port 428 proximate the distal end of the second inner tubular member 414 and a proximal guidewire port 426 proximate the proximal end of the second inner tubular member 414. Guidewire 430 may be extendable through guidewire lumen 436 .

The lumen of first inner tubular member 415 can define an auxiliary lumen 435 configured to longitudinally receive an elongated member, such as temperature probe 470, therethrough. Auxiliary lumen 435 may extend from the proximal end of catheter 410 to the distal end of catheter 410, with a proximal portion of temperature probe 470 extending proximal to auxiliary lumen 435 (e.g., proximal to catheter 410) and a distal portion of temperature probe 470 extending distal to auxiliary lumen 435 (e.g., distal to catheter 410).

The distal end portion 438 of the outer tubular member 413 may be a reduced diameter portion or neck portion that is secured to the first inner tubular member 415 and/or the second inner tubular member 414 to seal the injection lumen 434 adjacent the distal end 418 of the catheter shaft 412. For example, distal end portion 438 can include a tapered region where outer tubular member 413 tapers to a reduced inner and/or outer diameter at the distal end of outer tubular member 413 . Accordingly, the inner surface of the distal end portion of the outer tubular member 413 can be secured to the outer surface of the distal end portion of the first inner tubular member 415 and/or the outer surface of the distal end portion of the second inner tubular member 414 at the distal end portion 438. Outer tubular member 413 may be secured to inner tubular members 414, 415 by, for example, laser welding, hot jaws, or other thermal bonding, adhesive bonding, or other bonding as appropriate.

Catheter shaft 412 may include one or more fluid injection openings 440 (eg, holes, openings) located at the distal end region of catheter 410 . Fluid injection opening 440 may be in fluid communication with injection fluid lumen 434 and may be configured to allow injection fluid to exit catheter 410 from injection fluid lumen 434 proximate distal end 418 of catheter shaft 412 . For example, catheter shaft 412 can include a plurality of fluid injection openings 440 extending through the wall of outer tubular member 413 from the inner surface of outer tubular member 413 to the outer surface of outer tubular member 413 . Infusion fluid opening 440 may be of similar construction and arrangement as infusion opening 40 of catheter 10 described above.

Fluid injection openings 440 may be configured to expel infusion fluid F in a radially outward direction from each of fluid injection openings 440 to facilitate mixing of infusion fluid F with blood flowing through the vessel lumen. In other embodiments, fluid injection openings 440 may be oriented differently in such a manner as to allow injection fluid to be expelled from catheter shaft 412 in a generally distal direction, if desired.

Catheter shaft 412 may also include one or more fluid holes 450 (eg, openings, apertures) located in the distal end region of catheter 410 . A fluid hole can be in fluid communication with infusion fluid lumen 434 and can be configured to allow infusion fluid to pass from infusion fluid lumen 434 to auxiliary lumen 435 . For example, the catheter shaft 412 can include one or more fluid holes 450 extending through the wall of the first inner tubular member 415 from the outer surface of the first inner tubular member 415 to the inner surface of the first inner tubular member 415. Catheter shaft 412 may include one fluid hole 450 extending through the wall of first inner tubular member 415 to allow infusion fluid F to enter auxiliary lumen 435 from infusion fluid lumen 434, or catheter shaft 412 may include two, three, or more such fluid holes 450 as desired.

Fluid hole 450 may be a weep hole configured to allow infusion fluid to seep or exude slowly from infusion fluid lumen 434 into auxiliary lumen 435 . For example, fluid hole 450 may be configured to allow infusion fluid to ooze, drip, drip, ooze, or otherwise slowly seep into auxiliary lumen 435 . In some cases, fluid hole 450 may have a diameter of, for example, about 100 microns (0.100 millimeters) to about 300 microns (0.300 millimeters), about 100 microns (0.100 millimeters) to about 200 microns (0.200 millimeters), or about 200 microns (0.200 millimeters) to about 300 microns (0.300 millimeters).

Catheter system 402 may also include temperature probe 470 sized and configured to be disposed through auxiliary lumen 435 of infusion catheter 410 . Temperature probe 470 may be longitudinally operable through auxiliary lumen 435 relative to catheter 410 . Temperature probe 470 may include a temperature sensor 472 such as a thermistor or thermocouple attached to a distal end region of temperature probe 470 . One exemplary embodiment of temperature probe 470 is a fiber optic temperature sensor available from Neoptix. A temperature sensor 472 attached to the temperature probe 470 may be used to measure the temperature T _b of the blood flowing through the lumen of the vessel and the temperature T _m of the mixture of blood and infusion fluid flowing distal to the infusion fluid opening 440 . A temperature sensor 472 can be placed at a distance distal to the infusion opening 440 when taking temperature measurements of the blood and infusion mixture. In some cases, the distance may be about 3 centimeters or more, about 4 centimeters or more, about 5 centimeters or more, or about 6 centimeters or more to ensure that the infusion fluid F mixes thoroughly with the blood before reaching the temperature sensor 472. For example, the temperature sensor 472 can be positioned at a distance D of about 3 cm to about 8 cm, about 3 cm to about 6 cm, about 4 cm to about 8 cm, or about 4 cm to about 6 cm distal of the infusion fluid opening 440 on the catheter shaft 412.

A temperature probe 470 is actuated longitudinally with respect to the catheter 410 and a sensor 472 can be positioned within the auxiliary lumen 435 to obtain a measurement of the temperature _Tf of the infusion fluid. For example, sensor 472 may be positioned within auxiliary lumen 435 adjacent fluid bore 450 extending through first inner tubular member 415 . Infusion fluid F (eg, saline) may be delivered to the distal end region of catheter 410 through infusion fluid lumen 434 . For example, infusion fluid F may be provided to the distal region of catheter 410 at a pressure of about 1 atmosphere to about 30 atmospheres. A small amount of infusion fluid F can enter auxiliary lumen 435 from infusion fluid lumen 434 through fluid hole 450 . Thus, with the temperature sensor 472 positioned within the auxiliary lumen 435, the actual temperature T _f of the infusion fluid F at the distal end region of the catheter 410 can be measured and recorded. For example, temperature sensor 472 may be positioned adjacent fluid port 450 such that infusion fluid F entering auxiliary lumen 435 is in direct contact with temperature sensor 472 within auxiliary lumen 435 . In other examples, temperature sensor 472 may be otherwise positioned within auxiliary lumen 435 such that infusion fluid F within auxiliary lumen 435 is in direct contact with temperature sensor 472 within auxiliary lumen 435 .

Temperature probe 470 may include a visual marker system that includes markings or indicators 474 on a proximal portion of temperature probe 470 that can be used by medical personnel to determine the location of temperature sensor 472 relative to fluid injection opening 440 and/or fluid hole 450. A mark or indicator 474 may be placed on temperature probe 470 proximal to hub assembly 420 for direct observation by an operator. In some cases, the temperature probe 470 has a first mark or indicia 474 at a known position corresponding to when the temperature sensor 472 is positioned proximate to the fluid bore 450 , a second mark or indicia 474 at a known position corresponding to when the temperature sensor 472 is located at a first known distance (eg, 3 centimeters) distal to the catheter 410 and thus the fluid injection opening 440 , and a second mark or indicia 474 at a known position corresponding to when the temperature sensor 472 is positioned at the catheter 410 and thus the fluid injection opening 44 . A third mark or indicia 474 at a known position corresponding to when the temperature sensor 472 is at a second distance (e.g., 4 centimeters) distal to 0, a fourth mark or indicia 474 at a known position corresponding to when the temperature sensor 472 is at a third distance (e.g., 5 centimeters) distal to the catheter 410 and thus the fluid injection opening 440, and a fourth distance (e.g., 6 centimeters) distal to the temperature sensor 472 from the catheter 410 and thus the fluid injection opening 440. A fifth mark or indicator 474 or the like at a known location corresponding to the case may be included.

The measured temperature obtained by the temperature probe 470 can then be used to calculate the actual absolute blood flow of blood in the vessel at the target location, as well as other calculated parameters that can aid in the diagnosis and understanding of many pathophysiological conditions.

In accordance with a further aspect of the present invention, it was unexpectedly discovered by the inventors that the catheters described above using thermodilution to determine blood flow to effect disruption of occlusions within body cavities, particularly biological lumens, having essentially the same construction as described above for the embodiment of FIGS. A body lumen should be understood to mean any blood vessel in a living body through which blood flows, including blood vessels, arteries, coronary arteries, and the like. Living things can be humans or animals. A body or vessel occlusion can be any occlusion, such as, but not limited to, a thrombus, thrombosis, or blood clot.

Indeed, fluid outlet openings having a predetermined diameter in the range of about 50 micrometers to about 200 micrometers, in certain variations in the range of 50 microns to 150 microns, in more particular variations between 70 micrometers and 150 microns, or in other variations between 70 and 110 microns, and fluid outlet openings in the range of about 10 x 101,325 Pa or 10 atmospheres to about 50 x 101,325 Pa or 50 atmospheres, or according to variant embodiments, at least 2 By selecting a predetermined fluid pressure in the range of 0 x 101,325 Pa or 20 atmospheres or more to about 50 x 101,325 Pa or 50 atmospheres, or according to a further variant embodiment, in the range of at least 30 x 101,325 Pa or 30 atmospheres or more to about 50 x 101,325 Pa or 50 atmospheres, the fluid flow exiting the fluid exit opening is generally either a thrombosis or a thrombus. It was unexpectedly discovered by the inventors to have shear forces that cause

The selected size of the fluid exit openings depends on the value of the pressure of the fluid to be injected, which, as detailed above and below, also depends on the number of fluid exit openings present in the outer wall of the catheter.

According to a particular variant feature, there is at least one set of four equally spaced fluid outlet openings in the circumferential direction. The at least one set of four fluid outlet openings may be arranged in the same plane substantially perpendicular to the longitudinal axis of the container, or arranged in a quincunx in two separate parallel planes substantially perpendicular to the longitudinal axis of the container.

According to another particular variant feature, there are at least two sets of four fluid outlet openings equidistantly arranged in the circumferential direction, and finally, according to a further particular variant feature, there are at least three sets of four equidistantly arranged fluid outlet openings in the circumferential direction.

Under this new use of disruption of body lumen occlusions, communication with the central lumen, such as was required in the infusion catheter of FIGS. 1-10 and some embodiments of FIGS. 11-20, is not required to determine fluid temperature, as this communication is lacking in FIGS.

Accordingly, the catheter system of the present invention for the disruption of body obstructions within body vessels is shown in FIGS. 11-20 as well as FIGS. 1-10. Thus, the reference numbers for similar components are only incremented by 100 each time, as is well understood by those skilled in the art.

Referring now to FIG. 11, there is shown a catheter system 502 similar to that of FIG. 1 including an elongated catheter 510 having a catheter shaft 512 extending distally from a hub assembly 520 with a proximal end 516 attached to the hub assembly and a distal end 518 opposite the proximal end 516. The catheter shaft 512 may be dual lumen having a first fluid lumen 534 and a second lumen 536 for insertion of an elongated element, which may be a guidewire 530 extending along at least a portion of the catheter shaft 512 configured to advance the catheter 510 over the guidewire 530. For example, in some embodiments, catheter 510 may be an over-the-wire (OTW) catheter in which guidewire lumen 536 may extend the entire length of catheter shaft 512 from distal end 518 to proximal end 516, as shown in FIGS. 18 and 19, further discussed.

In other embodiments, such as those shown in FIGS. 11, 11A, 12-17 and 20, the catheter may be a single operator exchange (SOE) in which the guidewire lumen 536 extends only through the distal portion of the catheter shaft 512 or 912.

The catheter shaft 512 may include an outer tubular member 513 and an inner tubular member 514 disposed within and extending through a first fluid lumen 534 of the outer tubular member 514 such that said first fluid lumen 534 is defined between the inner tubular member 514 and the outer tubular member 513 and a second lumen 536 is defined by the inner tubular member 514.

In the SOE catheter configuration of FIG. 11, fluid lumen 534 is defined between the outer surface of inner tubular member 514 and the inner surface of outer tubular member 513 and naturally extends from proximal end 516 and distal end 518 .

One or more fluid exit openings 540 are located at the distal end region of the catheter configured to allow fluid to exit the catheter from the first fluid lumen 534 .

Hub assembly 520 may include a proximal port 522 in fluid communication with fluid lumen 534 . The control device 590 may include a fluid pressure means 592 disposed externally of the catheter beyond the proximal end 516 and coupled to the proximal port 522 to deliver the fluid into the first fluid lumen 534 at a pressure range predetermined to cause rupture of the obstruction upon exiting the fluid exit opening 540.

The catheter system may further comprise an elongated member 530 advanceable through a second lumen 536 of the catheter.

According to a variant, the elongated member may comprise a temperature sensor 532 located at the distal end portion of the elongated member 530 .

According to a further variation, temperature sensor 532 at the distal end portion of elongated member 530 can be positioned forward of catheter distal end 518 to measure temperature within blood vessel 580 shown in FIGS. 14-17.

A lumen 536 of the inner tubular member 514 may define an elongated member lumen 536, shown here as a guidewire lumen 536 having a distal port 528 proximate the distal end 518 and a proximal guidewire port 526 proximate the proximal end of the inner tubular member 514.

According to a further alternative embodiment, one or more fluid exit openings 540 extend through the wall of outer tubular member 513 from the inner surface of the outer tubular member to the outer surface of the outer tubular member.

According to a further variation, embodiment, the one or more fluid exit openings 540 are configured to produce a jet of fluid exiting the catheter, particularly radially substantially perpendicular to the surface of the outer tubular member 513, at a pressure sufficient to cause mechanical disruption of a body occlusion, such as the thrombosis T shown in FIGS.

In certain alternative embodiments, the one or more fluid exit openings 540 includes at least a set of four fluid exit openings 540 evenly spaced circumferentially around the outer tubular member, as shown in FIGS. In this embodiment of FIGS. 11, 11a, the four fluid exit openings are arranged in the same plane substantially perpendicular to the longitudinal axis of the catheter and thus also substantially perpendicular to the longitudinal axis of the body lumen 580. 12, 15 and 17, the four fluid exit openings 540a and 540b or 640a and 640b lie in two separate parallel planes substantially perpendicular to the longitudinal axis of the catheter and thus the longitudinal axis of the body lumen 580. These two parallel planes may be separated by a longitudinal distance x as in FIG. 2, such as about 0.5 millimeters, about 1 millimeter, about 2 millimeters, or about 3 millimeters apart.

In another particular alternative embodiment, the one or more fluid exit openings includes at least two sets of four fluid exit openings 840 and 940 evenly spaced circumferentially around outer tubular members 880 and 980, as shown in FIGS. 19 and 20, respectively.

In another particular alternative embodiment, one or more fluid holes 550 (FIG. 11) or fluid holes 650 (FIG. 13) are disposed in the distal end region of the catheter and are configured to allow fluid to pass from the first fluid lumen 534 to the second lumen 536, said one or more fluid holes 550 extending through the wall of the inner tubular member 536 from the outer surface of the inner tubular member to the inner surface of the inner tubular member.

According to a variant feature, the one or more fluid holes 550, 650 are one or more weep holes configured to allow fluid to seep into the second lumen.

According to alternative embodiments, one or more fluid holes 550, 650 have a diameter in the range of about 100 microns to about 300 microns.

According to an alternative embodiment, elongated catheter shaft 512 includes an elongated reduced diameter region 538 extending distally of one or more fluid exit openings 540 to the distal end of elongated catheter shaft 512 .

According to a further alternative embodiment, a first temperature sensor 760, 860 (see FIGS. 18, 19) is positioned within the first fluid lumen of the catheter shaft proximate to the one or more fluid exit openings 740, 840, the first temperature sensor 760, 860 configured for direct contact with the fluid within the lumen to measure the temperature of the fluid exiting the lumen through the one or more fluid exit openings 740, 840. It is

According to a further alternative embodiment, the catheter can further comprise a second temperature sensor 732 positioned outside the elongated reduced diameter region 724 proximate the distal end 718 of the elongated catheter shaft 710, as shown in FIG.

According to a further variant feature, the second temperature sensor 732 is positioned at least 4 centimeters distal to the one or more fluid exit openings 740 .

According to a further alternative embodiment, the distal end of the inner tubular member is sealingly secured to the distal end of the elongated catheter shaft.

As noted above, elongated member 530 may comprise a guidewire advanceable through inner tubular member 514 .

According to a further alternative embodiment, the guidewire 530 can include a temperature sensor 532 located at the distal end portion of the guidewire for measuring the temperature of the blood/fluid mixture within the body cavity distal to the one or more fluid exit openings 540.

According to a further variant embodiment, the catheter can comprise at least one pressure sensor P in the vicinity of at least one fluid exit opening 540 (Fig. 11), or 640 (Fig. 13), or 740 (Fig. 18), or 840 (Fig. 19), or 940 (Fig. 20).

According to a further variant embodiment, in all the embodiments of FIGS. 11-20, the fluid is a liquid selected from saline and blood compatible aqueous solutions. In alternative embodiments, the saline solution may include at least one clot or thrombolytic aid. These solubilizers are well known to those skilled in the art.

According to a further modified embodiment, in all of the embodiments of Figures 11-20, the fluid exit opening has a diameter in the range of about 50 microns (0.050 millimeters) to about 200 microns (0.200 millimeters). The diameter size selected is typically adapted to the fluid pressure, and the fluid pressure near the inlet or at least one fluid outlet opening of the catheter ranges between about 10×101,325 Pa or 10 atmospheres to about 50×101,325 Pa or 50 atmospheres.

According to alternative embodiments, the fluid exit opening has a diameter ranging from about 50 microns (0.050 millimeters) to about 150 microns (0.150 millimeters), or from about 70 microns (0.070 millimeters) to about 110 microns (0.110 millimeters).

According to a further variant embodiment, the pressure of the fluid near the inlet or at least one fluid outlet opening of said catheter is at least 20×10 1,325 Pa or 20 atmospheres or in the range between 30×10 1 ,325 Pa or 30 atmospheres and 50×10 1 ,325 Pa or 50 atmospheres. This pressure is particularly suitable for orifice sizes ranging from about 70 microns (0.070 millimeters) to about 150 microns (0.150 millimeters) or 110 microns (0.110 millimeters), and the pressure also depends on the number of fluid exit openings present in the outer wall of the catheter, as will be well understood by those skilled in the art.

With respect to the embodiments of FIGS. 1-10, all of the embodiments of FIGS. 11-20 can also include one or more radiopaque markers 552 (FIGS. 11 and 16), or 652 (FIG. 13), or 752 (FIG. 18), or 852 (FIG. 19) or 952 (FIG. 20) for the same reasons described for the embodiments of FIGS.

As shown in the drawings, FIG. 13 relates to a modified embodiment of a single operator exchange (SOE) catheter similar to that of FIG. Here, the catheter may include an outer tubular member 613 and an inner tubular member 614 disposed within and extending through a first fluid lumen 634 of the outer tubular member 614 such that said first fluid lumen 634 is defined between the inner tubular member 614 and the outer tubular member 613 and a second lumen 636 is defined by the inner tubular member 614. Additionally, catheter shaft 612 can extend distally from hub assembly 620 itself, which can include proximal port 622 in fluid communication with fluid lumen 634 . Control device 690 includes a fluid pressure means 692 disposed externally of the catheter beyond proximal end 616 and coupled to proximal port 622 to deliver said fluid to first fluid lumen 634 in a pressure range predetermined to cause rupture of said obstruction upon exiting fluid exit opening 640.

The catheter system may further comprise an elongated member 630 advanceable through a second lumen 636 of the catheter.

The catheter may include an inflatable balloon 620 attached to the distal region of catheter shaft 612 in this alternate embodiment similar to that of FIG. The balloon may include a proximal waist secured to the distal end of the outer tubular member 613 , eg, by heat bonding or adhesive, and a distal waist also secured to the distal end 624 of the inner tubular member 614 . In this alternate embodiment, a fluid lumen 634 extending along the catheter shaft can be in fluid communication with the interior of the inflatable balloon 620 to deliver said fluid to the inflatable balloon. Here, the inflatable balloon may include one or more fluid exit openings 640 extending through the wall of the balloon 640 and configured to allow fluid to exit the balloon 620 from the fluid lumen 634. It is well understood that balloon 620 is inflated by fluid pressure flowing within fluid lumen 634 . In one exemplary embodiment, as shown in FIG. 13, the balloon can include at least one set of four fluid exit openings 640 evenly spaced circumferentially around the balloon 620. In certain embodiments, the fluid exit openings may be located in the distal cone portion of balloon 620, as shown in FIG. 13, in the cylindrical body portion of balloon 620, or in both. As shown in FIG. 13, the catheter may be positioned to be blocked by the cone portion of balloon 620 against an anterior obstruction, such as a thrombosis T, clot, or cholesterol deposits, such that a jet of fluid causes mechanical or physical disruption of the obstruction T when the fluid exits under said predetermined pressure.

14-17 illustrate aspects of an exemplary method of disrupting an obstruction such as a T within body lumen 580 using the catheter system of FIG. As shown in FIG. 14, an elongated member 530 configured as a guidewire, here carrying a temperature sensor 532 attached to its distal region, can be advanced through a blood vessel 580 in a body cavity of an organism, such as a human or animal, to a desired target location T, i.e., an occlusion such as a thrombosis, clot, or cholesterol deposit, for destruction thereof.

Catheter 510 may then be advanced over guidewire 530 to target location T, as shown in FIGS. 15-17. Alternatively, the catheter 510 can be advanced over a conventional guidewire to the target location, after which the guidewire 530 with the temperature sensor 532 can be replaced if it is desired to measure the temperature within the blood vessel. If desired, the guidewire 530 can be withdrawn proximally and the temperature sensor repositioned adjacent the fluid hole 550 as shown in FIG. 16 to measure the temperature of the fluid near the exit opening 540. Additionally, a temperature sensor 532 on the guidewire 530 may be advanced to a distal location on the catheter, eg, a distance D from the fluid exit opening 540, as shown in FIG. This distance D may range from 3 centimeters to 6 centimeters or more for measuring and checking the temperature within blood vessel 580 .

Thus, according to another embodiment, the temperature of the infused fluid under pressure from the pressurizing means 592 is set to a desired value that may be useful in breaking the occlusion T while remaining compatible with blood. The fluid temperature may range between about 20°C or room temperature and about 35°C.

The fluid flow rate of fluid F can be set at any desired flow rate that, in combination with the fluid pressure, results in rapid rupture of the obstruction T. This fluid flow rate may range from about 15 ml/min to about 50 ml/min.

The pressure means may typically be a pressurized fluid (especially liquid) pump.

Another catheter embodiment is shown in FIG. 18 that is an over-the-wire (OTW) catheter and includes an elongated catheter 710 that also includes a catheter system 702 similar to that of FIG. Catheter shaft 712 may also be dual lumen having a first outer fluid lumen 734 and a second inner lumen 714 defined therein. The catheter shaft 712 may include a reduced diameter distal end region 724 that extends to the distal end 718 of the catheter shaft to aid in sliding of the catheter, and the lumen 714 acts as a sliding guide for an elongated element 730 that may be configured as a guidewire, similar to other OTW embodiments. Accordingly, the inner diameter of lumen 714 may be sized to approximate the diameter of guidewire 730 for proper guiding and sliding of the guidewire. Because catheter 710 is here an over-the-wire (OTW) catheter, guidewire lumen 736 can extend the length of catheter shaft 712 from distal end 718 to proximal end 716 . The hub assembly 720 has a specific fluid inlet 722 connected to a control device 790 including fluid pressure means 792 for injecting fluid under pressure into a fluid lumen 734 which exits through a fluid exit opening 740 to enable rupture of the occlusion T.

A pressure sensor P may be present near the fluid outlet opening 840 .

Another embodiment of a catheter system is shown in FIG. 19, a catheter system referenced 802 similar to that of FIG. The catheter shaft 812 may be dual lumen having a first outer fluid lumen 834 and a second inner lumen 836 for insertion of an elongated element, which may be a guidewire 830, extending along at least a portion of the catheter shaft 812 and configured to advance the catheter 580 over the guidewire 830. In that embodiment, catheter 810 is also an over-the-wire (OTW) catheter in which guidewire lumen 836 may extend the entire length of catheter shaft 812 from distal end 818 to proximal end 816 .

Hub assembly 820 also has a specific fluid inlet 822 connected to a controller 890 that includes fluid pressure means 892 for injecting fluid under pressure into fluid lumen 834 exiting through fluid outlet opening 840 .

A pressure sensor P may be present near the fluid exit opening 840 to measure the pressure near the fluid exit opening 840 .

As shown in the drawings, FIG. 20 relates to a further modified embodiment of a single operator exchange (SOE) catheter similar to that of FIGS. Catheter system 902 may include an elongated catheter 910 and possibly an associated temperature probe 970 and/or guidewire 930 . In many respects, catheter 910 may be similar to infusion catheter 10 shown in FIG. For example, infusion catheter 910 may include an elongated catheter shaft 912 extending distally from hub assembly 920 having a proximal end 916 attached to hub assembly 920 and a distal end 918 opposite proximal end 916 . Catheter shaft 912 may be a triple lumen catheter shaft comprising a first fluid lumen 934, a second auxiliary lumen 935 (e.g., a temperature probe lumen), and a third guidewire lumen 936 extending along at least a portion of catheter shaft 912 and configured to advance injection catheter 910 over guidewire 930.

Catheter shaft 912 may include an outer tubular member 913 and first and second inner tubular members 915 , 914 extending through lumens of outer tubular member 913 . A fluid lumen 934 may be defined by a portion of the lumen of the outer tubular member 913 outside the first and second inner tubular members 915,914. Hub assembly 920 may include a proximal port 922 in fluid communication with fluid lumen 934 . An infusion fluid, particularly a source of infusion fluid such as a liquid pump, syringe, etc., may be coupled to a proximal port 922 contained in the command central 990 and connected to a pressure means 992 that supplies fluid to the fluid lumen 934 and, in turn, to the fluid outlet opening 940. In other embodiments, catheter shaft 912 may be an extruded tubular member including, for example, three lumens extending therethrough.

The lumen of the second inner tubular member 914 may define a guidewire lumen 936 having a distal guidewire port 928 proximate the distal end of the second inner tubular member 914 and a proximal guidewire port 926 proximate the proximal end of the second inner tubular member 914. Guidewire 930 may be extendable through guidewire lumen 936 .

A lumen of first inner tubular member 915 may define an auxiliary lumen 935 configured to longitudinally receive an elongated member, such as temperature probe 970, therethrough. Auxiliary lumen 935 may extend from the proximal end of catheter 910 to the distal end of catheter 910, with a proximal portion of temperature probe 970 extending proximal to auxiliary lumen 935 (e.g., proximal to catheter 910) and a distal portion of temperature probe 970 extending distal to auxiliary lumen 935 (e.g., distal to catheter 910).

The distal end portion 938 of the outer tubular member 913 may be a reduced diameter portion or neck portion that is secured to the first inner tubular member 915 and/or the second inner tubular member 914 to seal the fluid lumen 934 adjacent the distal end 918 of the catheter shaft 912. For example, distal end portion 938 may include a tapered region where outer tubular member 913 tapers to a reduced inner and/or outer diameter at the distal end of outer tubular member 913 . Accordingly, the inner surface of the distal end portion of the outer tubular member 913 can be secured to the outer surface of the distal end portion of the first inner tubular member 915 and/or the outer surface of the distal end portion of the second inner tubular member 914 at the distal end portion 938. Outer tubular member 913 may be secured to inner tubular members 914, 915 by, for example, laser welding, hot jaws, or other thermal bonding, adhesive bonding, or other bonding as appropriate.

Catheter shaft 912 may include one or more fluid exit openings 940 (eg, holes, openings) located at the distal end region of catheter 910 . Fluid exit opening 940 may be in fluid communication with fluid lumen 934 and may be configured to allow infusion fluid to exit catheter 910 from infusion fluid lumen 934 proximate distal end 918 of catheter shaft 912 . For example, catheter shaft 912 may include a plurality of fluid exit openings 940 extending through the wall of outer tubular member 913 from the inner surface of outer tubular member 413 to the outer surface of outer tubular member 413 . Fluid exit opening 940 may be of similar construction and arrangement to exit opening 450 of catheter 510 described above.

Fluid exit openings 940 may be configured to expel fluid F in a radially outward direction from each of fluid exit openings 940 such that fluid F mechanically or physically disrupts an obstruction T present within container 980. In other embodiments, the fluid exit openings 940 can be oriented differently, such as to allow the fluid to exit under sufficient pressure to cause mechanical or physical disruption of the obstruction T, as desired. In Figures 13, 15 and 20 the formation of a cavity is visualized which symbolizes the beginning of the mechanical destruction of the occlusion T. Complete disruption occurs by moving the catheter back and forth several times along the length of the occlusion T, as described in the protocol further referenced.

In all embodiments, the catheter may be made from flexible, vascular compatible materials such as, but not limited to, polyethers, Pebax, HDPE, polyamides, polycarbonates, as is well known to those skilled in the art. Fluid exit openings can be easily created by micropulsing/ablation, such as with a laser. These exit holes can be made at a distance of 7-8 mm at the distal end of the catheter.

It will be appreciated that the catheter system of Figures 11-20 enables the method of the present invention to be carried out as follows.

A method of the present invention for performing disruption of a body obstruction within a body lumen of an organism comprises:
advancing a catheter to a desired location containing said obstruction within a body lumen, wherein the catheter is a catheter shaft including a proximal end and a distal end, the catheter shaft including an outer tubular member and at least one inner tubular member disposed within the outer tubular member; a first fluid lumen defined between the inner tubular member and the outer tubular member; and a second lumen defined by the inner tubular member; one or more fluid exit openings located in the distal end region of the catheter, configured to allow
delivering fluid to the distal end region of the catheter through the first fluid lumen and providing a pressure and duration to cause rupture of the occlusion within a predetermined pressure range to evacuate the fluid at a predetermined pressure;
including.

Several variations of the method result from varying embodiments of the catheter construction.

According to a particular variation, advancing the catheter within the body step includes using an elongated member that may be configured as a guidewire.

According to another particular variant, said catheter is provided with a temperature probe and said method comprises measuring, with said temperature sensor, the temperature of the fluid leaving the catheter or of the blood in front of the distal end of the catheter.

According to another particular variant, said method comprises
providing at least one temperature sensor at the distal end of the elongated member and positioning the elongated member at a location distal to the catheter to measure the temperature of the fluid-blood mixture distal to the catheter;
further includes

According to a further particular variation, the catheter includes one or more fluid holes located in the distal end region of the catheter near at least one said fluid exit opening, the one or more fluid holes being configured on the inner tube to allow fluid to flow from the first fluid lumen to the second lumen, the method comprising repositioning the elongated member at a position in front of said fluid holes for measuring the temperature of the fluid near the fluid exiting the catheter.

According to a particular method variant, said method further comprises providing said fluid exit opening having a diameter in the range between about 50 microns (0.050 millimeters) and about 200 microns (0.200 millimeters), particularly as described above, between 70 microns (0.070 millimeters) and about 150 microns (0.150 millimeters), or even 110 microns (0.110 millimeters). The fluid pressure near the inlet or at least one fluid outlet opening of said catheter ranges between about 10 x 101325 Pa or 10 atmospheres and about 50 x 101325 Pa or 50 atmospheres, in particular between at least 20 x 101325 Pa or 30 x 101325 Pa or 30 atmospheres and between about 50 x 101325 Pa or 50 atmospheres or more.

According to a particular variant, the catheter comprises at least one pressure sensor near at least one fluid outlet opening, said method comprising measuring the pressure of the fluid near said fluid outlet opening and correcting the pressure value of the fluid injected into the fluid lumen.

According to a further particular variant, said method further comprises providing said fluid as a liquid selected from saline and a blood compatible aqueous solution comprising at least one clot or thrombolytic adjuvant.

The following describes a clinical protocol for thrombus fragmentation with the catheter of the present invention described in any of Figures 11-20 during primary percutaneous coronary intervention or PCI.

BACKGROUND Thrombi are almost uniformly implicated in sudden coronary artery occlusion leading to acute myocardial infarction (AMI).

OBJECTS OF THE INVENTION The purpose of the present invention is to induce thrombus fragmentation by spraying saline perpendicular to the longitudinal axis of the artery to prevent large thromboembolism during balloon inflation and stent implantation.

Moreover, saline infusion has been shown to induce maximal and steady-state microvasodilation that may further contribute to preservation of microvascular function in the setting of AMI.

Protocol A patient is admitted with ST-segment elevation myocardial infarction or STEMI and an angiogram shows TIMI0 or TIMI1 flow in the causative artery. TIMI0 and TIMI1 are coronary artery permeability scores, TIMI0=complete occlusion, TIMI1=discrete opacification of the artery distal to the lesion.

The occlusion must be in an artery with a diameter of 3 mm or greater.

After angiographic documentation of complete or partial occlusion of the coronary arteries, a conventional guidewire is advanced across the thrombotic occlusion. This maneuver usually induces a partial recanalization that allows visualization of the vessel distal to the occlusion. This allows confirmation of the position of the wire within the lumen of the artery.

A catheter described for any of the embodiments of Figures 11-20, for example, has a length of 1403 mm and an outer diameter of less than about 1 mm. The catheter is connected to pressure means including an infusion pump or injector capable of delivering a constant flow rate of at least 20 mL/min. The infusion pump is set to a maximum of 700 PSI or about 50 atmospheres or about 50 x 101,325 Pa. The pump or injector is filled with saline at room temperature. Saline is made up with 1 L of water + 9 g of NaCl (0.9%).

After connecting to the pump, the catheter is flushed and advanced over the wire and positioned distally to the guide catheter.

Via the catheter, saline infusion is provided at a constant flow rate of 20 mL/min at a pressure of about 40 atmospheres or about 40×101325 Pa. The saline exits the catheter through at least four lateral holes so that the jet F is perpendicular to the longitudinal axis of the catheter and thus the longitudinal axis of the artery.

The catheter is slowly passed through the occlusion T and pulled back into the guiding while maintaining a substantially constant infusion rate. The passage is repeated up to 4 times.

The rest of the primary PCI is then left to the operator's discretion.

Those skilled in the art will recognize that aspects of the disclosure may be manifested in various forms other than the specific embodiments described and contemplated herein. Accordingly, changes may be made in form and detail without departing from the scope and spirit of the present disclosure as set forth in the appended claims.

Claims (33)

A catheter system for performing disruption of a body obstruction within a bodily lumen of a living organism, comprising a catheter shaft including a proximal end and a distal end, said catheter shaft including an outer tubular member, at least one inner tubular member disposed within said outer tubular member, a first fluid lumen defined between said inner tubular member and said outer tubular member, and at least one second lumen defined by said at least one inner tubular member; A catheter system comprising: one or more fluid exit openings disposed in a distal end region of said catheter configured to allow exit of said catheter from a fluid lumen; and fluid pressure means disposed externally of said catheter beyond said proximal end for delivering said fluid into said first fluid lumen at a pressure range predetermined to rupture said obstruction. The catheter system of claim 1, further comprising an elongated member advanceable through the second lumen of the catheter. 3. The catheter system of claim 2, wherein the elongated member comprises a temperature sensor located at a distal end portion of the elongated member. 4. The catheter system of claim 3, wherein the temperature sensor on the distal end portion of the elongated member is positionable forward of the distal end of the catheter to measure temperature within the blood vessel. The catheter system of any one of claims 1-4, wherein the one or more fluid exit openings extend through a wall of the outer tubular member from an inner surface of the outer tubular member to an outer surface of the outer tubular member. The catheter system of any one of claims 1-5, wherein the one or more fluid exit openings are configured to produce a jet of fluid exiting the catheter with sufficient pressure to cause mechanical disruption of the body occlusion. The catheter system of any one of claims 1-6, wherein the one or more fluid exit openings comprises at least a set of four fluid exit openings equally spaced circumferentially around the outer tubular member. The catheter system of any one of claims 1-7, wherein the one or more fluid exit openings comprises at least two sets of four fluid exit openings equally spaced circumferentially around the outer tubular member. The fluid outlet opening has a diameter between about 50 microns (0.050 millimeters) and about 200 microns (0.200 millimeters), and the fluid pressure near the inlet or at least one fluid outlet opening of the catheter ranges from about 10×101325 Pa, or 10 atmospheres, to about 50×101325 Pa, or 50 atmospheres, in particular, the fluid pressure near the inlet or at least one fluid outlet opening of the catheter is about 20 atmospheres. The catheter system of any one of claims 1-8, wherein the pressure ranges between x 101325 Pa or 20 atmospheres to about 50 x 101325 Pa or 50 atmospheres. The diameter of the fluid exit opening ranges from about 70 microns (0.070 millimeters) to about 150 microns (0.150 millimeters), or about 110 microns (0.110 millimeters), and the fluid pressure near the inlet or at least one fluid exit opening of the catheter is from about 20 x 101325 Pa or 20 atmospheres or 30 x 101325 Pa or 30 atmospheres to about 50 x 101325 Pa or 50 atmospheres. The catheter system of any one of claims 1-9, which ranges between 11. The catheter system of any one of claims 1-10, wherein one or more fluid holes are located in the distal end region of the catheter and configured to allow fluid to pass from the first fluid lumen to the second lumen, the one or more fluid holes extending through a wall of the inner tubular member from an outer surface of the inner tubular member to an inner surface of the inner tubular member. 12. The catheter system of claim 11, wherein the one or more fluid holes have diameters ranging from about 100 microns to about 300 microns. The catheter system of any one of claims 1-12, wherein the elongated catheter shaft includes an elongated reduced diameter region extending distally of the one or more fluid exit openings to the distal end of the elongated catheter shaft. A catheter system according to any preceding claim, wherein a first temperature sensor is disposed within the first fluid lumen of the catheter shaft proximate to the one or more fluid exit openings, the first temperature sensor configured to directly contact the fluid in the lumen to measure the temperature of the fluid exiting the lumen through the one or more fluid exit openings. 15. The catheter system of claim 14, further comprising a second temperature sensor positioned outside the elongated reduced diameter region proximate the distal end of the elongated catheter shaft. 16. The catheter system of claim 15, wherein the second temperature sensor is positioned at least 4 centimeters distal to the one or more fluid exit openings. A catheter system according to any preceding claim, wherein the distal end of the inner tubular member is sealingly secured to the distal end of the elongated catheter shaft. further comprising an elongated member including a guidewire advanceable through the inner tubular member;
said catheter is selected from an over-the-wire (OTW) catheter and a single operator exchange (SOE) catheter;
A catheter system according to any one of claims 1-17. 19. The catheter system of claim 18, wherein the guidewire comprises a temperature sensor, the temperature sensor positioned at a distal end portion of the guidewire to measure the temperature of the blood/fluid mixture within the body cavity distal to the one or more fluid exit openings. A catheter system according to any preceding claim, wherein the catheter comprises at least one pressure sensor near at least one fluid exit opening. The catheter system of any one of claims 1-20, wherein the fluid is a liquid selected from saline and a blood compatible aqueous solution containing at least one clot or thrombolytic adjuvant. 1. A method of performing disruption of a body occlusion within a body vessel of a living body, comprising:
advancing a catheter to a desired location within the bodily vessel containing the obstruction, the catheter comprising a catheter shaft including a proximal end and a distal end, the catheter shaft including an outer tubular member, at least one inner tubular member disposed within the outer tubular member, a first fluid lumen defined between the inner tubular member and the outer tubular member, and at least one second lumen defined by the inner tubular member; one or more fluid exit openings disposed at a distal end region of the catheter configured to allow exit of the catheter from the fluid lumen of
effecting delivery of fluid through the first fluid lumen to a distal end region of the catheter at a predetermined pressure range to expel the fluid at a predetermined pressure at a pressure and duration that causes rupture of the occlusion;
A method, including 23. The method of claim 22, wherein the catheter includes at least one set of four fluid exit openings disposed at the distal end region of the catheter and equally spaced circumferentially around the outer tubular member. 24. The method of claim 22 or 23, wherein the catheter comprises two sets of four fluid exit openings disposed at the distal end region of the catheter and equally spaced circumferentially around the outer tubular member. 25. The method of any one of claims 22-24, wherein advancing the catheter within the body step comprises using an elongated member. 26. The method of claim 25, wherein the elongated member is a guidewire and the catheter is selected from an over-the-wire (OTW) catheter and a single operator exchange (SOE) catheter. 27. A method according to any one of claims 22 to 26, wherein the catheter is provided with a temperature probe and the method comprises using the temperature sensor to measure the temperature of fluid exiting the catheter or blood in front of the distal end of the catheter. providing at least one temperature sensor at the distal end of the elongated member and positioning the elongated member at a location distal to the catheter to measure the temperature of the mixture of the fluid and the blood distal to the catheter;
The method of any one of claims 22-27, further comprising 3. The catheter includes one or more fluid holes located in the distal end region of the catheter near at least one of the fluid exit openings, the one or more fluid holes configured on the inner tube to allow the fluid to flow from the first fluid lumen to the second lumen, the method comprising repositioning the elongated member at a position in front of the fluid holes to measure a temperature of the fluid in the vicinity of the fluid exiting the catheter. 29. The method of any one of 2-28. Includes a step that provides a fluid exit opening with a diameter of about 200 microns (0.200 mm at 0.200 mm) to about 200 microns (0.050 mm), and at least one fluid pressure near the exit of the caterpillar or at least one fluid exit. The method according to any one of claims 22 to 29, which is the range between PA, 10th and about 50 × 101, 325 Pa, that is, 50 atm. providing said fluid exit openings having a diameter in the range between about 70 microns (0.070 millimeters) and about 150 microns (0.150 millimeters), wherein said fluid pressure near the inlet of said catheter or at least one fluid exit opening is between about or at least 20 x 101325 Pa or 20 atmospheres, or between at least 30 x 101325 Pa or 30 atmospheres and about 50 x 101325 Pa or 50 atmospheres. 31. The method of any one of claims 22-30, which is a range. The method of any one of claims 22-31, wherein the catheter includes at least one pressure sensor near at least one fluid exit opening, and wherein the method comprises measuring the pressure of the fluid near the fluid exit opening and correcting the fluid pressure value injected into the fluid lumen. 33. The method of any one of claims 22-32, comprising providing the fluid as a liquid selected from saline and a blood compatible aqueous solution comprising at least one clot or thrombolytic adjuvant.

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