JP2023515276A - Intravascular delivery system and method for percutaneous coronary intervention - Google Patents

Abstract

The subject guide catheter extension/pre-dilatation system includes an outer delivery sheath, an inner member extending within the sheath, and a mechanism for engagement/disengagement of the inner member with respect to the sheath. The inner member is configured with a tapered distal tip having a delivery microcatheter and a pre-dilatation balloon member attached to the tapered distal tip adjacent the microcatheter. The outer delivery sheath and inner member are modified for operation of different engagement/disengagement mechanisms. A delivery microcatheter provides improved mobility of the balloon member to the treatment site in an atraumatic, rapid, and convenient manner. During cardiac surgery, guidewires and guide catheters are advanced within blood vessels to the vicinity of the treatment site. The inner member and outer delivery sheath are then advanced in engagement over a guidewire inside the guide catheter to the treatment site. Upon reaching the treatment site, the balloon member is inflated for pre-dilatation treatment. The inner member is then separated from the outer delivery sheath and pulled back, and the stent is delivered inside the outer delivery sheath to the treatment site. [Selection drawing] Fig. 1

Description

(Cross reference to related applications)
This PCT patent application claims priority from currently pending U.S. Patent Application Serial No. 16/793,120, filed February 18, 2020, which is is a continuation-in-part (CIP) of currently pending U.S. Patent Application Serial No. 16/132,878, filed September 17, 2018, which is currently pending is a continuation-in-part (CIP) of US patent application Ser.

(INCORPORATION BY REFERENCE)
Currently pending U.S. Patent Application Nos. 16/793,120, 16/132,878, and 15/899,603 are incorporated herein by reference.

The present invention relates to minimally invasive devices used therapeutically in the human vasculature, e.g. The system relates to a delivery system enhanced with a pre-dilatation guide catheter extension feature.

In addition, the present invention provides atraumatic, convenient, and rapid delivery of various interventional devices, such as pre-dilatation balloons or stents, as well as coronary arteries within the patient's body to facilitate percutaneous revascularization. or other vascular) medical device designed for replacement of catheters.

Further, the present invention provides exceptional deliverability of the subject interventional device over conventional balloon angioplasty catheters, combined with substantially atraumatic transferability to the lesion site for treatment. We are working on an intravascular delivery system with a small, tapered soft distal tip that enables.

Additionally, the present invention relates to an intravascular guide catheter extension/pre-dilatation system that uses an inner member (interventional device delivery catheter subsystem) positioned in place within an outer member (outer delivery catheter subsystem). , the inner member is formed with a distal coil reinforcing tapered portion that interfaces with the slightly tapered distal end of the outer member. These include a low profile and substantially low profile at the interface between the distal ends of the outer member (outer catheter) and the inner member (inner catheter) at the transition point where the distal portion of the inner catheter engages or enters the outer member. dimensioned to form a "seamless" transition to This construction is extremely beneficial for smooth passage of the inner and outer members as a single unit along a diseased vessel without traumatizing the tissue.

Further, the present invention relates to an intravascular guide catheter extension/pre-dilatation system consisting of an outer catheter (member) and an inner catheter (member) displaceable inside the outer catheter along with the outer catheter. A distal tapered soft tip is formed as an expandable flexible low durometer elastomeric member having an inner diameter smaller than the outer diameter of the distal portion of the inner catheter in the region of engagement with the outer catheter in the contracted state. . This configuration achieves a reversible elastic engagement between the outer and inner catheters at the distal end, which causes the flared distal end of the outer catheter to collapse when the inner catheter is removed from the outer catheter. It ensures that the outer diameter is returned to its original diameter and reduces (or eliminates) "fishmouthing" at the distal junction of the outer and inner members as the system navigates between bends in the vessel.

Further, the present invention relates to an intravascular guide catheter extension/predilatation system configured with outer and inner catheters that are displaceable relative to each other, wherein the proximal end of the outer catheter provides enhanced reinforcement, shaft mid-stent advancement, , prevention of stent embolization, increased flexibility, and improved flow rate of contrast injection fluid.

Additionally, the present invention can be used to (1) controllably engage the inner and outer members for movement together within a guiding catheter along a guidewire, or (2) as needed in an endovascular procedure. Designed with a shaft mid-interconnection (locking) mechanism that is activated/deactivated by the physician to either separate the inner and outer catheters to retract the inner catheter from the outer member (catheter). intravascular guide catheter extension/pre-dilatation system. The inner member can carry an interventional device (such as a pre-dilatation balloon member or stent) attached to its tapered coil-reinforced distal end, and the locking mechanism provides smooth, reversible engagement/disengagement. Provide instructions. In addition, this mid-shaft reversible lock prevents forward movement of the inner member relative to the outer member when advancing or retracting the system so that the location of the distal "seamless" transition of the inner and outer catheters is It ensures that the subject system remains essentially axially fixed in place during movement.

Additionally, the present invention is configured with a tapered coil reinforced shaft at the distal end for mounting and carrying a balloon member, and the balloon member integral with the coil reinforced delivery sheath of the outer catheter to the desired treatment site. It relates to an intravascular guide catheter extension/pre-dilatation system that provides "seamless" entry and smooth delivery.

Additionally, the present invention addresses an intravascular guide catheter extension/pre-dilatation system featuring a monorail microcatheter embodiment with rapid exchange (RX) functionality for applications with short guidewires and distal end of the inner catheter. A tapered soft end is configured with a coil reinforced microcatheter that provides additional kink resistance and "pushability" while still maintaining flexibility for navigating tortuous vasculature.

Coronary occlusive disease or other diseases in the peripheral vasculature are often treated with balloon angioplasty and/or stenting. Advancement of a revascularization device, such as a balloon or stent delivery system, within a vessel to a treatment site can be difficult for a physician when the vessel is tortuous and/or calcified.

Coronary stents, commonly used in a procedure called percutaneous coronary intervention (PCI), are tubular stents that are placed in the coronary arteries that supply the heart to keep the arteries open for treatment of coronary heart disease. Device. Stents help improve coronary blood flow and reduce chest pain, and have been shown to improve survival in cases of acute myocardial infarction.

Treatment of occluded coronary arteries with stents follows essentially the same process as other angioplasty procedures, but there are important differences. A compressed stent attached to a balloon significantly reduces the flexibility of the balloon, making it difficult to advance smoothly through the coronary arteries. This can make it difficult or impossible to deliver the stent to the treatment site, and the undeployed stent can dislodge from the delivery balloon.

Intravascular imaging can be used to assess lesion thickness and hardness (calcification), which affects stent deliverability. Cardiologists use this information to decide whether to treat a lesion with a stent and, if so, what type and size of stent to use. Stents, both bare-metal stents and drug-eluting stents, are most often sold as a unit with the stent in a collapsed (pre-expanded) configuration mounted outside a balloon catheter.

Physicians can perform "direct stent placement", in which the stent is advanced through the blood vessel to the lesion and expanded. However, to facilitate stent delivery in more difficult lesions, it is common to pre-dilate the occlusion prior to stent delivery.

Predilation is accomplished by passing a conventional balloon catheter through the lesion and inflating it to increase the diameter of the lesion. A balloon catheter is a type of "soft" catheter with an inflatable balloon at its tip that is used in catheterization procedures to widen narrow openings or passageways in the body. After predilatation, the predilatation balloon is removed and a stent catheter is advanced through the vessel to the lesion, inflated, and left at the lesion site as a "scaffold", a permanent implant to widen the vessel.

Balloon catheters used in angioplasty have either over-the-wire (OTW) or rapid exchange (RX) designs. The balloon catheter is slid over a guidewire that can be loaded into the balloon catheter through the hub (in the over-the-wire variant) or the RX port (in the rapid exchange variant of the balloon catheter). In over-the-wire balloon catheters, a concentric lumen for passage of the guidewire extends through the catheter from the proximal hub to the balloon, while in rapid exchange (RX) balloon catheters, a tube for guidewire passage is provided. A lumen extends from the RX port through the interior of the catheter to the balloon to allow passage of a guidewire.

Revascularization devices typically employ guide catheters to deliver such devices to the site of treatment. Using only a guiding catheter to "back up" the advancement of revascularization devices into the coronary arteries can be limited and difficult, especially when a stent is deployed using a radial access guiding catheter.

Guide catheter extension systems have been designed and used in cardiac surgery to facilitate delivery of revascularization devices to the desired site.

For example, guide extension systems such as the "Guideliner™" are manufactured by Teleflex. This guide extension system is described in US Pat. No. 8,292,850 to Root et al. Root et al. (U.S. Pat. No. 8,292,850) describe a coaxial guide catheter threaded through the lumen of the guide catheter for use with an interventional cardiology device insertable into bifurcated arteries branching from the aorta. there is

Root's coaxial guide catheter extends through the lumen of the guide catheter, past its distal end, and is inserted into the bifurcated artery. Root uses a guide extension supported by a tapered inner catheter. The purpose of the inner catheter is to avoid vessel damage when advancing the guide extension into the proximal portion of the coronary vessel to provide additional "back-up" support for stent or balloon delivery. to provide an atraumatic tip for

Another guide extension system such as the "Guidezilla™" is designed and manufactured by Boston Scientific. This guide extension system is described in US Pat. No. 9,764,118 to Anderson et al. Anderson's guide extension system includes a proximal portion having a proximal stiffness, a distal portion having a distal stiffness different from the proximal stiffness, and a smooth transition between the proximal and distal portions. A pushing member is used that has a transition portion that provides a A distal tubular member is attached to the push member and has an outer diameter greater than the push member outer diameter.

US Patent Application Publication No. 2017/0028178 to Ho describes a guide extension system that uses a slit catheter that can expand upon insertion of a balloon or stent delivery system. Additionally, Ho's guide extension uses a rigid push rod to assist in delivery of the guide extension to the treatment site.

The "Guideliner™" and "Guidezilla™" systems, as well as Ho's system, provide an additional "backup" for delivering balloon dilatation catheters and/or stent delivery catheters to the intended site of treatment. It supports the concept of partially advancing the guide extension system through the guide catheter and into the coronary artery to achieve support.

The function of these guide extensions is to allow closer access to the lesion to provide additional support in traversing the lesion to be treated with the interventional device. However, passage of a pre-dilatation balloon catheter or stent delivery system through the lesion to be treated, despite the additional support, may result in fibrosis, calcification, previous stent struts within the lumen, and/or lesion site. can still be difficult or nearly impossible due to the angular shape of the

One of the limitations of currently used guide extenders is that they use large diameter cylindrical distal ends that are relatively blunt. Due to the relatively large profile of the distal edge, the deliverability of the guide extension is often limited and can only be advanced to the proximal or intermediate portion of the coronary artery to be treated. Even after balloon pre-dilatation of a lesion, it is extremely rare, if not impossible, to be able to reach the guide extension to the actual lesion being treated with angioplasty or stenting. These "blunt-ended" tubular guide extension devices are relatively frequently subject to failure and can lead to serious dissection complications. Published data indicate that "blunt-ended" tubular guide extension systems may fail in up to 20% of cases and cause severe coronary artery dissection in about 3% of cases.

US Patent Application Publication No. 2011/0301502 to Gill describes a catheter with a longitudinal extension that allows the diameter of the positioning device to be smaller than the stent delivery system. However, the Gill device does not envisage an inner catheter to allow easy and atraumatic traversal of the treated lesion. Gill's system simply acts as a cover for the stent delivery system and can be removed after advancing the stent delivery system because of the longitudinal stretch.

Although the idea of a tapered part inside the guide extension catheter is found in Root's device, prior art systems used very short tapers, envisioning the taper as an elongated integral member of the overall system. Nor does it envisage attaching a pre-dilatation balloon to a tapered delivery microcatheter that is brought to the desired treatment area. Furthermore, the prior art does not envision a substantially "stepless" boundary between the inner catheter and the outer guide extension inside the vessel, rather than reversibly mating the inner and outer catheter members together. , or locked to make the whole system easily moveable as one unitary device.

Root or other prior art systems have a very small profile elongated tip that is believed to be beneficial in achieving coaxial delivery of the guide catheter extension/balloon system to and past the lesion of interest. No balloon (and/or stent) delivery system is described, anticipated, or envisioned. Such an embodiment has not heretofore been commercially available and the description of the tapered tip inner device is only as a mechanism for bringing the blunt tip of the guide catheter extension proximally from the guide catheter. is intended, and is in no way intended as a mechanism for delivering a balloon (and/or stent) to and past a target treatment area within a vessel; and that the unitary nature of the outer member and the "stepless" interconnection permit passage of the outer delivery "sheath" member across the lesion of interest.

Accordingly, a device and method that allows delivery of the distal portion of a tubular guide extension system to and ideally past the lesion to be treated is the Guideliner™. It is believed to have significant advantages over conventional guide extension devices such as (Teleflex) or "Guidezilla™" (Boston Scientific).

None of the traditional balloon catheters (over-the-wire or quick exchange) are integrated with an outer delivery sheath and are advanced to and past the lesion site atraumatically within the vessel. It does not use a tapered delivery microcatheter at the distal end of the catheter to which an interventional device (eg, balloon or stent, etc.) is secured. Further, any conventional balloon catheter operates to allow the conventional balloon catheter and outer delivery sheath to move together as a single unit, with forward movement of the balloon catheter relative to the outer delivery sheath. Interconnected to the outer delivery sheath (guide catheter extension subsystem) via an interconnection mechanism that is deactivated to allow withdrawal of the balloon catheter from the outer delivery sheath while preventing displacement. Do not mean.

Delivery of an interventional device (e.g., pre-dilatation balloon) along with a guiding catheter extension subsystem (such as an outer delivery sheath) to and past the lesion in a substantially atraumatic and convenient manner It would be highly desirable and efficient to provide an intravascular delivery system that can.

In addition, a reinforced distal tip shape with a compact tapered distal tip shape with a "seamless" distal boundary to ensure that the system can be atraumatically advanced to the lesion for treatment. It would be highly desirable to provide an intravascular delivery system having an outer catheter and an inner catheter that both feature distal ends.

In addition, percutaneous revascularization procedures can be facilitated by using a balloon attached to the coil-reinforced tapered distal tip of an inner balloon catheter housed within the outer delivery sheath of the outer catheter. Considered desirable, the inner balloon catheter is distal to the tapered distal tip for carrying interventional devices (pre-dilatation balloons and/or stents) to and past the lesion to be treated. elongated tapered coil reinforced microcatheter. This is believed to represent a significant improvement over conventional guide catheter extension and pre-dilatation systems.

U.S. Pat. No. 8,292,850 U.S. Pat. No. 9,764,118 U.S. Patent Application Publication No. 2017/0028178 U.S. Patent Application Publication No. 2011/0301502

It is therefore an object of the present invention to deliver interventional devices (such as balloons or stents) to and past occlusive lesions in coronary arteries in an efficient and minimally traumatic manner. It is an object of the present invention to provide a medical device for intravascular application which can be entered.

Another object of the present invention is a compact profile that is beneficial in achieving "transversality" of pre-dilatation balloons (or other interventional devices) and enhances efficient and safe distal delivery of guide extension devices. and using a coaxial highly flexible delivery catheter device having an outer catheter and an inner catheter that interface with each other at the distal end in a "seamless" manner. .

It is a further object of the present invention to deliver a pre-dilatation balloon (or another interventional device) to a lesion of interest within a diseased human coronary artery to be treated with angioplasty (or stenting) and/or The use of a highly flexible coil reinforced distally tapered elongated microcatheter tip to deliver past the target lesion.

A further object of the present invention employs an outer catheter (outer delivery sheath subsystem) and an inner catheter (interventional device delivery subsystem) housed inside and exchangeably connected to the outer sheath of the outer catheter. A guide catheter extension/pre-dilatation system, both deliverable into and beyond a lesion area for treatment within a vessel, wherein the inner catheter guides in a substantially atraumatic manner. By providing a guide catheter extension/pre-dilatation system having at its distal end a delivery tapered micro-catheter with a pre-dilatation balloon member (or other interventional device) that slides along the wire. be.

A further object of the present invention is to provide a guide catheter extension subsystem (outer member) integrated with a pre-dilatation balloon (or other interventional device) subsystem (inner member), wherein the outer member and the inner member are coupled together (via a locking mechanism) such that they are displaced together (as a “whole system”) along the guidewire to the lesion site. After the pre-dilation procedure, the guide catheter extension subsystem (configured with the outer delivery sheath) can be disconnected from the inner member and advanced past the lesion as needed. The inner member (interventional device delivery subsystem) can then be withdrawn. When desired for surgery, the outer delivery sheath of the outer member remains within the guide catheter to facilitate delivery of the stent (or other interventional device) inside the outer delivery sheath to the lesion site. be able to. The outer delivery sheath can then be withdrawn after the stent (or other interventional device) has been delivered to the lesion and deployed for final treatment.

A further object of the present invention is to combine both the inner and outer members into a single unit for convenient and safe delivery of the pre-inflated balloon and outer sheath to and past the treatment site. Another object of the present invention is to provide a guide catheter extension/pre-dilatation system that includes a "locking mechanism" operably coupled between the inner and outer members (outer sheath) for passing together as a guide catheter.

A further object of the present invention is to achieve easy passage of a balloon (or other interventional device) and guide extension system to treat the interior of vascular structures in an atraumatic manner in order to expedite cardiac surgery. A guide extension system configured with a pre-dilatation balloon (or other interventional device) delivery catheter deliverable to a site, wherein the exposure is less than would be achieved using conventional systems. A guide that allows percutaneous coronary intervention to be performed with very low radiation dose exposure and has the added advantage of virtually no risk of stent embolization or drug loss from the stent delivery system (due to drug-eluting stents). It is to provide an extension system.

It is a further object of the present invention to be displaceable relative to each other and still increasingly flexible, yet reinforced by coil reinforcement along its length to achieve improved contrast injection flow and embolic protection. The tapered distal end of the outer catheter is in strong contact with the distal portion of the inner catheter and substantially a step at the interface between the inner and outer catheters. To provide an intravascular guide catheter extension/pre-dilatation system that can be elastically stretched to form a smooth outer surface.

The present systems and methods address an intravascular delivery system configured to controllably displace along a guidewire within a vessel of a subject. The system is formed with a proximal portion, a distal portion, and an intermediate portion located between the proximal portion and the intermediate portion. The system includes an outer member formed by a flexible, substantially cylindrically contoured elongated outer delivery sheath that defines a sheath lumen having proximal and distal ends. An outer delivery sheath extends between the intermediate portion and the distal portion and is configured with a tapered outer tip at the distal end of the sheath lumen. A tapered outer tip of the outer member located at the distal end of the outer delivery sheath defines a wall extending in a cylindrical fashion between distal and proximal edges of the tapered outer tip. configured with. The tapered outer tip wall has an inner diameter and an outer diameter. The inner and outer diameters of the walls of the tapered outer tip gradually decrease in dimension from the proximal edge to the distal edge of the tapered outer tip. A proximal (wire or hypotube) element (push or pull) connected to the tubular structure of the outer member provides improved conformability to the interior of the guiding catheter and rigidity in conventional guide extension catheters (such as Root). It may be of small profile and "flexible" (not "rigid") to allow a smaller profile than a typical "push" element. This is the "pushability" of the "system as a whole" achieved through a locked integral connection between the outer catheter (with hypotube push/pull elements) and the inner catheter (guide extension tube). Therefore it becomes possible.

The system further includes an inner member (inner catheter) having an elongated body defining an internal channel extending along the longitudinal axis. The inner member extends internally along the sheath lumen of the outer member (outer catheter) in a controllable relationship with the outer delivery sheath. The elongated body of the inner member has a tapered distal portion, the tapered distal portion having an outer diameter and comprising a tapered delivery catheter having an elongated body of a predetermined length. be done. A tapered delivery catheter of the inner member is displaceable past the distal end of the outer sheath. It is important that the inner diameter of the wall of the tapered outer tip of the outer member is smaller than the outer diameter of the tapered distal portion of the inner member in the region where the two elements form the distal junction.

An interconnection mechanism is operably coupled between the inner member and the outer member and is controllably actuated to operate the guide catheter extension/pre-dilatation subsystem in an engagement mode or a separation mode of operation. In the engaged mode of operation, the inner and outer members of the guide catheter extension subsystem engage for controllable common displacement along the guidewire. This is true even though the connected pusher (push/pull element) of the outer member has a small profile and is flexible (as flexible as or more flexible than the outer tubular sheath of the outer catheter). It also allows for improved "pushability" of the system (having the outer member connected and locked to the inner member). In the decoupled mode of operation, the inner and outer members are separated to retract the inner member from the outer member after a pre-dilatation procedure or stent delivery.

The distal portion of the inner member interfaces on its outer surface with the inner surface of the tapered outer tip of the sheath lumen. The dimensional transition between the outer diameter of the outer tip of the sheath lumen and the outer diameter of the distal tip of the inner member forms a substantially stepless boundary transition therebetween.

A tapered outer tip of the outer member has a resiliently expandable configuration. At its proximal end (also referred to herein as the mid-shaft portion of the outer member), the outer sheath is configured with an inlet opening whose circumference extends beyond the circumference of the tubular body of the outer sheath. In some embodiments, the entry opening at the proximal end of the outer sheath is funnel-shaped.

The outer sheath is preferably reinforced along its length. The outer member includes a distal soft tip encapsulant encasing the outer member's reinforced sheath at its distal end. The distal soft tip encapsulating material is a flexible, low durometer elastomeric material having a durometer value that increases from the distal end to the proximal end of the sheath.

The outer member further includes a distal lubricious liner sandwiched between the outer surface of the outer sheath and the inner surface of the distal soft tip encapsulant.

The delivery catheter is preferably a microcatheter. The microcatheter is formed of a flexible material and can have varying flexibility along its length, with the flexibility of the microcatheter increasing towards its distal end.

A balloon catheter is attached to the tapered distal portion of the inner member adjacent the tapered delivery microcatheter, and the inflation lumen extends within the inner member between the proximal and distal portion balloon members. and provides a fluid passageway between the external balloon inflation system and the balloon member. The balloon member can assume an inflated state or a deflated state. In the deflated state, the balloon member is displaced within the vessel. The balloon member is controllably deformed to an expanded configuration after being positioned at least in alignment with the treatment site for a pre-dilatation procedure.

The elongated body of the inner member and the microcatheter are reinforced with coils along their lengths.

An outer catheter pusher/puller element configured with a flat at its distal end is secured to the proximal end of the outer sheath of the outer catheter. Preferably, the pusher/puller of the outer member is configured with a channel extending along its length communicating with the sheath lumen to prevent embolization. This proximal (push and pull) element connected to the outer sheath tubular structure of the outer catheter provides a better fit inside the guiding catheter and a stiffer "push" in conventional guide extension catheters (such as Root). It may be of small profile and "flexible" (not "rigid") to allow for a smaller profile than the '' element.

The interconnection mechanism is a snap configured with a proximal coupler located at the proximal end of the sheath of the outer member (catheter) and a cooperating element located on the outer surface of the elongated body of the inner member (catheter). A mating locking mechanism can be included. The proximal coupler can include a distal solid ring and an intermediate split ring positioned a predetermined distance from the solid ring, while the cooperating members include a shift intermediate locking ring, a square annular ring, A member selected from the group comprising a snap-fit cage, and other similar members. A cooperating member is attached to the outer surface of the elongated body of the inner member. A locking engagement between the outer member and the inner member is achieved when the cooperating members are engaged and locked in a snap-fit manner between the distal solid ring and the intermediate split ring. The pusher/puller elements and couplers of the outer catheter prevent deformation during antegrade or retrograde motion of the outer member and provide a mid-shaft coupler (this section) as a stent or other device passes through the mid-shaft of the outer catheter. Also referred to herein as the proximal coupler), it may be made of a memory metal (eg, nitinol, etc.) to prevent deformation.

The proximal coupler, at its proximal end, reinforces the funneled proximal ostium of the outer member to prevent damage or permanent deformation of the funneled proximal ostium caused by displacement of the inner member or stent delivery system at the funneled ostium. further including a proximal angled split ring that prevents The coupler and shaft intermediate inlet can have an inlet opening (or "mouth") whose circumference is greater than the circumference of the flexible tubular outer sheath structure of the outer member.

The subject intravascular system further includes a guidewire that can be advanced within the subject vessel to at least the treatment site, and the guide catheter extension subsystem is configured to controllably displace along the guidewire. In one embodiment of the system, a resilient outer jacket encases the inner member at least along its proximal end and encases the inner member pusher/puller at least along its distal end. The proximal end of the inner member is connected to the pusher/puller by fusing the elastic outer jacket to the length of the proximal end of the inner member and snugly supporting the pusher/puller of the inner member within the elastic outer jacket. be.

The push-pull element of the outer catheter (or its outer jacket) may be color coated to have a distinguishing color to distinguish it from the normal gray or silver color of the push-pull element of the inner catheter as well as the coronary guidewire. . Alternatively, the elastic outer jacket of the inner member may be color coated to distinguish the pusher/puller of the inner member from the color of other elements of the system of interest for the surgeon's convenience.

These and other objects and advantages of the present invention will become apparent to those skilled in the art upon review of the detailed description of the invention in conjunction with the patent drawings.

1 schematically illustrates a subject guide catheter extension/pre-inflation system advanced to a target site within a coronary artery; 1 schematically illustrates the subject guide catheter extension/pre-inflation system, showing assembled inner and outer catheters. 1 schematically illustrates the subject guide catheter extension/pre-inflation system, detailing the inner catheter; 1 schematically illustrates the subject guide catheter extension/pre-inflation system, detailing the middle portion of the subject system; FIG. 4 is a view of the middle section of the inner catheter of interest, showing a longitudinal cross-section of the inflation lumen hypotube interconnected with the inflation lumen distal shaft within the inner catheter. FIG. 4 is a view of the middle portion of the subject inner catheter, detailing a longitudinal cross-section of the skived portion of the inflation lumen hypotube. FIG. 3B is a view of the middle section of the inner catheter of interest, showing a longitudinal section of the inner catheter showing the RX guidewire (GW) port formed in the inflation lumen distal shaft. FIG. 3D is a view of the middle section of the inner catheter of interest, showing an isometric view of the RX port section of the inner catheter shown in FIG. 3C. FIG. 10B shows a longitudinal cross-sectional view of the inner catheter detailing the distal end of the inflation hypotube at its junction with the inflation lumen distal shaft. Fig. 3 shows the distal portion of the subject system, showing the inflation balloon member; Fig. 3 shows the distal portion of the subject system, showing the balloon member in a deflated state; 11 shows the distal portion of the subject system, detailing the inflation sensate chamber/balloon junction. FIG. 6A shows a longitudinal section of the distal portion of the inner catheter of interest, detailing the 3 mm distal and proximal tapers of the balloon. FIG. 6B shows a longitudinal section of the distal portion of the inner catheter of interest, detailing the 6 mm distal and proximal tapers of the balloon. Fig. 3 shows the distal tip of the outer catheter; The interfaces at their distal ends of the inner and outer catheters are detailed, showing the tapered distal end of the inner catheter. The interfaces of the inner and outer catheters at their distal ends are shown in detail, and the connection point between the inner and outer catheters is shown somewhat enlarged. FIG. 9A depicts an alternative embodiment of a resiliently expandable distal tip of an outer catheter configured with an expandable split ring. FIG. 9B depicts an optional embodiment of an elastically expandable distal tip of an outer catheter configured with an expandable tip scaffold. FIG. 9C depicts an alternative embodiment of a resiliently stretchable distal tip of an outer catheter configured with a slit. FIG. 9D depicts an alternative embodiment of a resiliently stretchable distal tip of an outer catheter configured with a slit. FIG. 10A shows a side view of an alternative embodiment of the proximal portion of the outer catheter of interest. FIG. 10B shows a side view of an alternative embodiment of the proximal portion of the outer catheter of interest. FIG. 10C shows an isometric view of an alternative embodiment of the proximal portion of the outer catheter of interest. FIG. 10D shows a side view of an alternative embodiment of the proximal portion of the outer catheter of interest. FIG. 10E shows an isometric view of an alternative embodiment of the proximal portion of the outer catheter of interest. FIG. 10F shows a side view of an alternative embodiment of the proximal portion of the outer catheter of interest. FIG. 10G shows an isometric view of an alternative embodiment of the proximal portion of the outer catheter of interest. FIG. 11A details the coupler design at the proximal end of the outer catheter and shows an isometric view of the flattened hypotube pusher. FIG. 11B details the coupler design at the proximal end of the outer catheter and is an isometric view of the proximal end of the outer catheter. FIG. 11C details the design of the coupler at the proximal end of the outer catheter and shows a side view of the coupler at the proximal end of the outer catheter featuring a snap-fit locking mechanism. Figure 12A shows an alternative embodiment of the proximal portion of the subject outer catheter and is an isometric view of the proximal coupler. Figure 12B shows an alternative embodiment of the proximal portion of the outer catheter of interest and is an isometric view of the encapsulated proximal coupler. FIG. 12C shows an alternative embodiment of the proximal portion of the subject outer catheter and is a side view of the encapsulated proximal coupler. Figure 13A shows an isometric view of yet another embodiment of the proximal coupler at the proximal end of the outer catheter. Figure 13B shows an isometric view of yet another embodiment of the proximal coupler at the proximal end of the outer catheter. FIG. 14A shows a weld ring embodiment for the proximal entry of the outer catheter, showing a weld ring coupler. FIG. 14B shows a weld ring embodiment for the proximal entry of the outer catheter, showing an encapsulated weld ring coupler. FIG. 15A shows a further alternative embodiment of the proximal coupler of the outer catheter and is a side view of the circular profile window of the funnel. FIG. 15B shows a further alternative embodiment of the proximal coupler of the outer catheter and is an isometric view of the circular profile window of the funnel. Figure 15C shows a further alternative embodiment of the proximal coupler of the outer catheter and is a side view of the triangular window of the funnel. Figure 15D shows a further alternative embodiment of the proximal coupler of the outer catheter and is an isometric view of the triangular window of the funnel. FIG. 16A is an illustration of the hypotube pusher flushing lumen concept, showing an isometric view of the proximal coupler of the outer catheter coupled to the pusher. FIG. 16B is an illustration of the flushing lumen concept of the hypotube pusher and is a cross-sectional isometric view of FIG. 16A showing the flow path within the pusher. FIG. 16C is a diagram of the flushing lumen concept of the hypotube pusher showing the procedure for injecting flushing fluid between the inner and outer catheters. FIG. 17A shows the shaft mid-annular circular ring locking mechanism of interest, showing the "unlocked" mode of operation. FIG. 17B shows the shaft mid-annular circular ring locking mechanism of interest, showing the "locking engagement" mode of operation. FIG. 17C shows a subject shaft mid-toroidal circular ring locking mechanism and is a view of an annular circular ring in the subject locking mechanism. Figure 18A details the annular circular ring locking mechanism of interest shown in Figures 17A and 17B, and is configured with a locking pocket for engagement with the annular circular ring (of Figure 17C). It shows a coupler. FIG. 18B is a longitudinal cross-sectional view of the inner/outer catheter locked together, detailing the toroidal circular ring locking mechanism of interest shown in FIGS. 17A and 17B. FIG. 19A shows an alternative thematic embodiment of a locking mechanism featuring a mid-shaft "square" annular ring, showing an inner catheter with a ring-shaped locking mechanism. FIG. 19B shows an alternative thematic embodiment of the locking mechanism featuring a mid-shaft "square" annular ring, showing the ring of the inner catheter mated to the proximal coupler of the outer catheter. FIG. 19C shows an alternative thematic embodiment of the locking mechanism featuring a shaft intermediate "square" annular ring, showing a cross-sectional view of the square annular ring. Figure 10 shows an alternative "snap-fit cage" locking mechanism, showing an inner catheter with a welded cage lock. An alternative "snap-fit cage" locking mechanism is shown, showing cage locking by welding the inner catheter fitted to the proximal coupler of the outer catheter. FIG. 10 is an isometric view of the welded cage elements showing an alternative "snap-fit cage" locking mechanism; FIG. 12 is a side view of another embodiment of the proximal coupler of the outer catheter featuring two locking slots; FIG. 22A depicts a monorail microcatheter embodiment of the subject system and shows an isometric view of the monorail microcatheter embodiment. FIG. 22B depicts a monorail microcatheter embodiment of the subject system and shows a side view taken along line AA. FIG. 13A details an embodiment of the subject monorail microcatheter and shows an isometric view of the proximal portion of the inner catheter connected to the inner catheter hypotube pusher. FIG. 11A is a detailed view of an embodiment of the subject monorail microcatheter, detailing the proximal end of the pusher on a somewhat enlarged scale; FIG. FIG. 14 is a side view of the proximal portion of the inner catheter connected to the hypotube pusher, detailing the subject monorail microcatheter embodiment; FIG. 24A shows an isometric view of an embodiment of the coil reinforced balloon catheter of the subject system. FIG. 24B shows a side view of an embodiment of the coil reinforced balloon catheter of the subject system.

1-24B illustrate a guide catheter extension subsystem (also referred to herein as an outer catheter or outer member) and an interventional device delivery subsystem (herein, cooperating under surgeon control during cardiac surgery). The subject intravascular delivery system 10 is shown including an inner catheter or inner member (also referred to herein as an inner catheter or inner member). Although the interventional device delivery subsystem can be used to deliver a variety of cardiac interventional devices, in one of the embodiments, by way of example only, the scope of the invention is limited to this particular embodiment. Instead, the subject interventional device delivery subsystem will be further described as being configured for delivery of a balloon member to perform a pre-dilatation procedure.

In the exemplary embodiment described herein, the subject system 10 is referred to herein as a guide catheter extension/pre-dilatation system that can be used in cardiac surgery with guidewire 12 and guide catheter 14. can be done. As shown in FIG. 1, in the early stages of heart surgery, a guidewire (GW) 12 is moved into a blood vessel 16 by a surgeon. Guide catheter 14 is advanced along guidewire 12 through vessel 16 (eg, the aorta, etc.) to a position adjacent ostium 18 of coronary artery 20 . The guidewire 12 can be used in cardiac surgery to guide a guide catheter 14, followed by a subject guide catheter extension/pre-dilatation system 10 (guide catheter 14), as detailed in the following paragraphs. 14) can extend within the artery 20 toward the target location 22 .

As shown in FIGS. 2A-2C, the subject guide catheter extension/pre-dilatation system 10 includes a balloon catheter sub-system 34 (also referred to herein as an inner catheter, inner member, or pre-dilatation sub-assembly) and a guide. It includes a catheter extension subsystem 36 (also referred to herein as an outer catheter). Inner catheter 34 interacts with outer catheter 36 and can be engaged or disconnected from outer catheter 36 as required in cardiac surgery.

The subject system 10 includes a proximal portion 38, a distal portion 40, an intermediate portion extending between the proximal portion 38 and the distal portion 40 and interconnecting the proximal portion 38 and the distal portion 40. and portion 42 . A pre-dilatation balloon member 44 is retained on the distal portion 40 of the inner catheter 34 . Additionally, the distal portion 40 of the inner catheter 34 can be configured with an elongated tapered microcatheter 46, as detailed in the following paragraphs.

The subject guide extension/pre-dilatation system 10 extends within the lumen (inner channel) 48 of the guide catheter 14, as shown in FIG. To ensure that the target location 22 is reached and possibly past the target location 22, the subject guide extension/pre-dilatation system 10 extends past the distal end 50 of the guide catheter 14 and deep into the coronary artery 20. It is advanced through catheter 14 . The subject system 10 extends past the distal end 50 of the guide catheter 14 to provide adequate reachability of the pre-dilatation balloon 44 to the target location 22 and extends past the ostium 18 of the coronary artery 20 . This stabilizes the positioning of guide catheter 14 and allows for improved accessibility of subject system 10 to coronary arteries 20 and target site 22 .

As shown in FIGS. 1, 2A and 2B, 3C and 3D, 4, 5A-5C, and 6A, guidewire 12 extends through guide catheter extension/pre-dilatation system 10. , exit system 10 with the distal ends of GW 12 past outermost end 52 of distal portion 40 and the proximal ends of GW 12 at intermediate portion 42 .

In operation, the inner catheter 34 and the outer catheter 36 are coupled together and advanced (as a single unit) along the guide wire 12 inside the guide catheter 14 positioned within the blood vessel 16 and distal to the guide catheter 14 . It extends past the proximal end 50 to reach the target lesion site 22 . Once the subject balloon catheter subsystem (inner member) 34 has reached the lesion site 22 and the balloon member 44 is aligned with the lesion site 22, the intended pre-dilatation procedure can be performed. Once predilation has been performed, the outer catheter (also referred to herein as outer member) 36 is advanced across the lesion as an integral unit with inner catheter (also referred to herein as inner member) 34. after which the inner catheter 34 can be disconnected from the outer catheter 36 in order to withdraw the inner catheter from the outer catheter.

Alternatively, after performing the predilation procedure, the inner catheter 34 can be disconnected from the outer catheter 36 while the outer catheter 36 is advanced across the dilated lesion. Additionally, the outer catheter 36 may be left near the lesion after pre-dilatation and removal of the inner catheter 34 .

In either situation, the outer member (catheter) 36 left in the vicinity of the lesion after predilatation can be used to deliver the stent inside the outer member (catheter) 36 to the lesion site. . Once the stent has been placed (deployed) at the lesion site, outer member 36 is removed from guide catheter 14 .

As presented in further paragraphs, forward displacement of the inner catheter 34 inside the outer catheter 36 is prevented in the subject system. Exclusively, a posterior displacement or removal displacement of the inner member 34 relative to the outer member 36 is allowed to support retraction of the inner member from the outer member after predilation of the lesion.

2A-2C, the proximal portion 38 of the subject guide extension/pre-dilatation system 10 includes a balloon inflation hub 56 (best shown in FIG. 2B) of the inner member 34 and a proximal portion of the outer member 36. Represented by posterior end 58 .

2B, 3A-3D, 4, and 5C, inner member (also referred to herein as a balloon catheter subsystem or pre-dilatation balloon delivery subsystem) 34 includes an inflation hub 56 and a pre-dilatation balloon delivery subsystem. It is configured with an internal inflation channel 60 extending between the dilatation balloon member 44 . Internal inflation channel 60 connects balloon inflation system 62 (shown schematically in FIG. 2B) and balloon member 44 for controlled inflation/deflation of balloon member 44 as prescribed by cardiac surgery. serves as a path for inflation air between

An internal inflation channel 60 is formed by an inflation lumen hypotube 64 and an inflation lumen distal shaft 66 interconnected in an overlapping relationship with each other in a fluid tight manner.

An inflation hub 56 located at the proximal end 68 of the inner member 34 has an internal conical channel 70 connected to the balloon inflation system 62 (as shown schematically in FIG. 2B) by a proximal opening 72. Configured.

Balloon inflation system 62 may be a manual or automated system. In a preferred automated embodiment, balloon inflation system 62 includes an electronic subsystem, a pneumatic subsystem, and control software with a corresponding user interface. The electronic subsystem, under the control of control software, powers a solenoid pressure valve (fluidly connected to balloon inflation hub 56) to control the pressurization/depressurization of balloon member 44 by fluid or air flow. supply.

As shown in FIG. 2B, the inner conical channel 70 of the balloon inflation hub 56 is configured with a distal opening 74 connected to the inflation lumen hypotube 64 . The proximal end of the inflation lumen hypotube 64 extends into an internal conical channel 70 of the balloon inflation hub 56 in a fluid tight manner to support the passage of inflation air between the balloon member 44 and the inflation system 62 . is connected to the distal opening 74 of the .

The inflation lumen hypotube 64 extends through the entire length of the proximal portion 38 and a portion of the intermediate portion 42 of the subject system 10 and extends through a distal end 78 at the distal portion 40, as shown in FIGS. 2B and 4 . end with.

A flexible serrated member 80 is provided at the proximal end 76 of the inflation lumen hypotube 64 connected to the distal end 82 of the balloon inflation hub 56, as shown in FIG. 2B. A serrated flexible member 80 supports the proximal end 76 of the inflation lumen hypotube 64 and provides flexible bending of the structure when manipulated by the surgeon.

As shown in FIGS. 2A-2C, 3A-3D, 4, and 5C, inflation lumen distal shaft 66 extends along intermediate portion 42 between proximal portions 38 and distally. End with part 40. FIG. 3A details the junction between inflation lumen hypotube 64 and inflation lumen distal shaft 66 . Inflation lumen hypotube 64 does not extend all the way through inner member 34 and terminates at distal end 78 (as shown in FIGS. 2B and 4).

3B-3D, inflation lumen hypotube 64 has a shaved distal portion 90 coaxially wrapped by the wall of inflation lumen distal shaft 66, thus expanding the inflation lumen hypotube. 64 cooperates with inflation lumen distal shaft 66 for controlled inflation/deflation of balloon member 44 as required in cardiac surgery, as shown in FIGS. It provides a sealed fluid communication between the balloon inflation system 62 and the interior chamber 92 of the balloon member 44 .

2B and FIGS. 3C and 3D illustrate that inflation lumen distal shaft 66 is configured with a rapid exchange (RX) guidewire (GW) port 94 where GW lumen 96 begins at its proximal end 98. is shown. GW lumen 96 extends between RX GW ports 94 inside inflation lumen distal shaft 66 the entire length of distal portion 40 of inner catheter 34 . GW lumen 96 forms an inner channel having a proximal end 98 corresponding to RX GW port 94 and a distal end 100 corresponding to outermost distal end 52 of distal portion 40 of inner member 34 . . In distal portion 40 , GW lumen 96 extends past distal end 102 of inflation lumen distal shaft 66 , as shown in FIGS. 6A and 6B . A distal end 100 of GW lumen 96 defines a gradually tapered portion 104 that may be in the form of delivery microcatheter 46 .

2A-2B, 5A-5C, 6A-6B, and 24A-24B, an inner catheter (also referred to herein as a balloon catheter subsystem) 34 includes a distal portion 40. with a tapered distal portion (also referred to herein as a tapered distal tip) 162 . Tapered distal portion 162 includes pre-dilatation balloon member 44 secured to tapered distal portion 162 adjacent microcatheter 46 . A pre-dilatation balloon member 44 is secured to a tapered distal portion (tip) 162 of the inner member to support a pre-dilatation/stenting procedure as required to treat the patient's heart.

Balloon member 44 has a proximal portion 112 and a distal portion 114 . Balloon member 44 is coupled to delivery microcatheter 46 with proximal portion 112 coupled to distal end 102 of inflation lumen distal shaft 66 and distal portion 114 of balloon 44 coupled to the outer surface of microcatheter 46 . Attached (fixed) to distal portion 40 in close proximity.

As shown in FIGS. 5A-5C, the pre-dilatation balloon 44 is attached at its proximal portion 112 to the proximal portion 204 of the distal tip 162 aligned adjacent to the outer tip 164 of the sheath 120. As shown in FIGS. and is attached at its distal portion 114 to the distal end 166 of the distal portion (tip) 162 of the inner member 34 .

The balloon member 44 can intermittently assume a deflated (collapsed) configuration and an inflated (expanded) configuration. A contracted (collapsed) configuration is used during insertion and/or withdrawal of the subject system from a blood vessel. The balloon is inflated (expanded) when in place (target site 22) to dilate the vessel for pre-dilatation procedures or stenting procedures (where a stent is delivered to the treatment site over the balloon). Compress plaque. Upon inflation, balloon 44 assumes the inflated/open configuration shown in FIGS. 2A and 2B, 5A, 5C, 6A and 6B, and 24A and 24B for pre-dilation of diseased vessels. take. Upon deflation, balloon member 44 assumes the deflated configuration shown in FIG. 5B.

Balloon 44 can have a smooth surface or a "chocolate" configuration. A "chocolate" balloon catheter is an over-the-wire balloon dilation catheter with a braided shaft and an atraumatic tapered tip. The balloon, when inflated, is constrained by a nitinol structure that creates small "pillows" and grooves in the balloon.

2A, 2C, 5A-5C, 7, 8A and 8B, 9A, 9C and 9D, 10A-10G, 11C, 12B and 12C, 13A and FIGS. 13B, 14B, 15A-15D, 16A and 16B, 17A and 17B, 18A and 18B, 19B, 20A and 20B, 21, and 24A and 24B. For reference, an outer catheter (also called a guide catheter extension subsystem) 36 is formed with a cylindrical outer delivery sheath 120 having an inner channel 122 extending inwardly therealong. ing. A coupler mechanism 130 is formed at a proximal end 132 of cylindrical sheath 120 in surrounding relationship.

At the proximal end 58, the outer catheter 36 includes an outer member pusher (also referred to herein as a pusher/puller) 134, which is shown in FIGS. 10B-10G, 11A-11C, 12A. 12C, 13A-13B, 14A-14B, 15A-15D, 16A-16B, 17A-17B, 18A-18B, 19B, and 22 Additionally, in one embodiment, it has a circular wire proximal portion 136 and a flattened distal portion 138 that may be welded or otherwise fixedly attached to the proximal end 132 of the sheath 130 . It may be a solid wire capable of In another embodiment, push-pull element 134 may be constructed of hypotube.

Alternatively, a circular pusher wire can be welded to a flat wire, which is welded or otherwise rigidly secured to the proximal end 132 of the sheath 120 .

In yet another alternative embodiment of the outer member 36, a circular wire can be welded or otherwise securely affixed to two flat wires, which are then attached to the sheath 120. is welded or otherwise secured to the proximal end 132 of the .

The flat profile of the pusher wire portion ensures that when the inner member 34 is inserted into the outer member (catheter) 36, the pusher wire is positioned inside the proximal coupler 130 and sheath 120 of the outer member 36 as required in surgery. It is welded to the proximal coupler 130 of the outer sheath 120 so as not to create an obstruction for rotational or longitudinal movement of the inner catheter 34 of the outer sheath 120 . The proximal push/pull element 134 advances or retracts with the outer tubular sheath 120 and is preferably flexible (not rigid). The pusher/puller 134 may be flexible (not rigid) such that its flexibility along its longitudinal axis matches or exceeds the flexibility of the tubular outer delivery sheath 120 of the outer catheter 36 . exceed.

For the convenience of a surgeon performing a coronary interventional procedure in manipulating the outer member 36 to position the outer delivery sheath 120 along with the balloon delivery subsystem 34 at a desired location relative to the lesion 22 within the diseased vessel; The outer catheter pusher 134 can be provided at its proximal end with a proximal handle 140 shown in FIG. 10F.

The proximal push/pull element 134 (consisting of wire or hypotube) connected to the tubular structure 120 of the outer member should have a compact profile and be flexible (not "rigid"). achieves a better fit inside the guide catheter and a smaller profile than the rigid "push" elements in conventional guide extension catheters (such as Root). This is possible because of the "pushability" of the "system as a whole" achieved through the locked integral connection between the outer catheter (with hypotube pushing element) and the inner catheter (guide extension tube). become.

In addition, the inner catheter (inner member) 34 facilitates withdrawal of the inner member 34 from the outer member 36 as required in coronary interventional procedures, as well as facilitating the withdrawal of the inner member 34 therebetween, during various stages of cardiac surgery. To control engagement/disengagement, an inner member pusher (also referred to herein as a pusher/puller) 142 (shown in FIG. 2A) may be provided that may be attached to the inflation hub 56 . The inner member pusher/puller 142 may be configured with an inner member pusher/puller handle for convenience to the treating surgeon.

A mechanism for enabling the handles of the pushers of the inner and outer members to be additionally releasably locked with respect to each other to enhance unitary cooperation of the inner and outer members in the engaged mode of operation. (detailed in US patent application Ser. No. 15/899,603, incorporated herein by reference).

Inner member 34 may be in either an over-the-wire configuration or an RX configuration. In one of the embodiments detailed herein, guidewire 12 is routed to the proximal end of tubular inflation lumen distal shaft 66, as shown in FIGS. 3C and 3D and FIG. It extends through the formed RX GW port 94 into an inner channel 146 of the GW lumen 96 and along the inner channel 146 of the GW lumen 96 . At the distal portion 40 of the subject system 10, the guidewire 12 is delivered (at the tapered portion 104) as shown in FIGS. 2A-2B, 5A-5B, and 6A-6B. It extends within the GW lumen along the tapered microcatheter 46 and exits the distal end 100 of the GW lumen 96 at the outermost end 52 of the inner member 34 .

Outer delivery sheath 120 of outer member 36 is fabricated from a flexible cylindrical tubular body 150 that extends substantially the length of intermediate portion 42 of system 10 of interest. By manipulating outer member pusher 134 , the surgeon actuates joint advancement of outer delivery sheath 120 and inner member 34 along guide catheter 14 . Once the pre-dilation procedure is performed (as detailed in further paragraphs), the surgeon manipulates outer member pusher 134 and/or inner member pusher 142 to push inner member 34 against sheath 120 of outer member 36 . controls the desired linear posterior displacement of the .

As shown in FIGS. 8A-8B and 9A-9D, the boundary between the outer tip 164 of the sheath 120 and the distal tip 162 of the inner member 34 is inward relative to the outer tip 164 of the sheath 120. Facilitates displacement of distal tip 162 of member 34, essentially facilitating displacement of distal tip 162 relative to outer tip 164 of sheath 120 as required in cardiac surgery.

The distal end 160 of the sheath 120 as well as the outer tip 164 are formed of a flexible material through which the distal tip 162 of the inner member 34 can be easily retracted. Flat wire helical coils may be used at distal end 160 and outer tip 164 of sheath 120 .

At its proximal end 132, the sheath 120 of the outer catheter 36 has an entry "opening" (or "opening") whose circumference exceeds the circumference of the outer member flexible tubular sheath 120, as shown in FIGS. 10A-10G. mouse”) 210 . The entrance 210 (also referred to herein as the "mouth") to the inner channel 122 of the sheath 120 can be configured in a variety of variations. For example, as shown in FIG. 10A, the inlet 210 has an eccentric opening (as shown in FIG. 10A) or is contoured with concentric obtuse angles (as shown in FIGS. 10B and 10C), Alternatively, it has a funnel shape 211 with concentric slopes (as shown in FIGS. 10D and 10E) or with concentric concave contours (as shown in FIGS. 10F and 10G). The pusher 134 is mounted at a predetermined point on the proximal inlet 210 of the funnel-shaped outer catheter.

As shown in FIGS. 2A, 2C, 7, and 8A and 8B, the outer delivery sheath 120 of the outer catheter 36 has a proximal end 132 located at the intermediate portion 42 of the subject system 10 and a distal end. It extends between the distal end 160 located in the proximal portion 40 . In the distal portion 40 of the subject guide catheter extension/pre-dilatation system 10, the inner member 34 includes FIGS. Constructed of a tapered configuration 104 having a distal tapered portion (also referred to herein as a distal tapered tip) 162 that may be formed with the microcatheter 46, as shown in FIGS. 24A and 24B. be done. Microcatheter 46 is a long, thin member having a length in the cm range, eg, 1-3 cm. Microcatheter 46 has a tapered conical profile at its distal end 52 with a diameter not exceeding 1 mm. Microcatheter 46 may be integrally formed with tapered distal tip 162 of inner member 34 .

At distal end 160, outer delivery sheath 120 is interconnected with distal tip 162 of inner member 34, as shown in FIGS. 2A, 5A-5C, 7, and 8A-8B. It is formed with an outer tip 164 having a tapered conical profile configuration. Outer tip 164 of outer member 36 provides a smooth distal taper transition between distal end 160 of sheath 120 and distal portion 40 .

2A, 5A and 5B, 6A and 6B, 8A and 8B, 22A and 22B, and 24A and 24B, distal tip 162 of inner catheter 34 extends outside sheath 120. It is shown to have a gradually tapered configuration from the point of interconnection with tip 164 to the distal end 166 of distal tip 162 . The microcatheter 46 extends from the distal end 166 of the distal tapered portion 162 of the inner member 34 (approximately 1-3 cm long) in an integral connection and terminates at the outermost distal end 52 .

The subject guide catheter extension/pre-dilatation system 10 is characterized in that the distal portion of the microcatheter 46 is more flexible and compliant than the proximal portion of the microcatheter delivery device and has a significantly smaller profile than the guide catheter. Varying the durometer of the plastic (polymer) component from the proximal portion of the outer delivery sheath to the distal portion (i.e., , higher durometer in the proximal portion compared to the distal portion), and/or varying the frequency (pitch) of the turns of the helical coil of wire in the microcatheter 46 in the direction from the proximal portion to the distal portion; can be configured to have a differential flexibility of the microcatheter which is more flexible at the distal portion.

Additionally, the system 10 can include radiopaque wires such that the balloon member 44, microcatheter 46, and outer delivery sheath 120 are easily visualized using fluoroscopy. Distal tip 162 (as shown in FIGS. 5A and 6A and 6B) may include radiopaque markers 264, 266 near proximal and distal portions 112, 114 of balloon 44. is assumed. Radiographic markers 264 , 266 allow the surgeon (operator) to visualize the position of balloon member 44 relative to lesion location 22 .

In addition, the outermost distal tip 52 of the microcatheter delivery portion 46 and the tip 160 of the sheath 120 are marked with one or more radiopaque markers 268, to allow the surgeon to distinguish the radiographic markers; 270 (shown in FIGS. 2B and 5A), which when the microcatheter has passed an occlusive lesion and a balloon member carried in close proximity to the microcatheter is held in place. It is especially important.

As shown in detail in FIG. 7, in one embodiment, outer catheter 36 is configured with a catheter shaft coil reinforcement system 170 disposed (or otherwise embedded) in inner surface 152 of sheath 120 . Preferably, a lubricious liner 172 is positioned inside shaft 120 . A shaft stiffening coil 170 may be positioned inside the shaft 120 in contact with the lubricious liner 172 , i.e., in surrounding relation to the surface of the lubricious liner 172 that covers the inner surface 152 of the shaft 120 . A distal soft tip jacket 174 is attached to the distal end of outer catheter shaft 120 along longitudinal axis 176 of outer catheter 36 .

Distal soft tip jacket 174 may be adhered to shaft 120 at end 175 (as shown in FIG. 7) or may cover a length of outer surface 173 of shaft 120 .

Distal soft tip jacket 174 extends past coil reinforcement 170 and lubricious liner 172 at distal end 160 of shaft 120 and terminates in tapered portion 178 having distal edge 184 and proximal edge 182 .

Lubricious liner 172 may be formed from a PTFE material. Distal soft tip jacket 172 may be formed of a highly flexible low durometer elastomeric Pebax material that transitions along longitudinal axis 176 to a high durometer toward proximal end 132 of sheath 120 .

7 and 8A-8B, in one of the preferred embodiments, the inner diameter of sheath 120 at inner surface 152 is approximately 0.048 inches, while the outer diameter of shaft 120 at outer surface 173 is approximately 0.048 inches. is 0.058 inches. The inner diameter at the distal edge 184 of the tapered portion 178 of the outer catheter 36 is approximately 0.045 inches, while the outer diameter at the distal edge 184 of the tapered portion 178 is approximately 0.047 inches. The slope between the outer diameter of sheath 120 (0.058 inch) and the outer diameter of taper 178 (0.047 inch) defines the taper of the outer surface, while the inner diameter of sheath 120 (0.048 inch) and the distal The slope between the inner diameter (0.045 inch) of taper 178 at edge 184 defines the taper of the inner surface. A distal wall 180 of tapered portion 178 has a reduction in thickness from a boundary 182 (between sheath 120 and tapered portion 178) to an outermost edge 184 of tapered portion 178 of distal soft tip jacket 174. .

As shown in FIG. 7 in conjunction with FIGS. 8A and 8B, the outer diameter of the inner catheter tapered element 104 is equal to the outer catheter distal tip inner diameter (0.045 inches) at the outermost distal edge 184 . has an outer diameter of about 0.046 inches, which is about 0.001 inches greater than the This difference between the outer diameter of the tapered element 104 of the inner catheter 34 and the inner diameter at the distal edge 184 of the outer tip 164 of the outer catheter is the difference in the tapered portion 178 when interfering with the tapered element 104 of the inner catheter. Causes stretching of the distal soft tip jacket 174 . Such a configuration provides a substantially seamless transition between the distal tip of the inner catheter 34 and the distal tip of the outer catheter 36, as well as the tapered element 178 of the outer catheter 36 allowing the distal tip of the inner catheter 34 to be slid. Provides a compact profile for the distal end due to compression. When the inner catheter 34 is removed, the elastomeric properties of the distal tip of the distal soft tip jacket 174 of the outer catheter 36 allow the tapered portion 178 to return to its original inner diameter (0.045 inch).

In the disengaged mode of operation, the inner diameter of wall 180 of tapered outer tip 164 of outer member 36 is less than the outer diameter of inner member 34 . In the engaged mode of operation, the tapered outer tip 164 of the outer member 36 and the inner member 34 meet the outer diameter of the tapered outer tip 164 of the sheath lumen 120 and the outer diameter of the distal portion of the inner member 34 . The dimensional transitions between the diameters interact to form a substantially stepless boundary transition therebetween.

With further reference to Figures 9A-9D, for tapered portion 178, several embodiments of expandable tapered designs are contemplated. As shown in FIG. 9A, elasticity in the distal tapered portion 178 of the outer catheter 36 is attached to the tapered portion 178 allowing the distal outer tip 164 to expand (when interfacing with the inner catheter 34). is augmented by an expandable split ring 190. The expandable split ring 190 has a slit 192 that allows the ring 190 to expand and contract in response to interference at the distal end between the inner and outer catheters. This construction provides additional reinforcement to prevent permanent deformation of the tapered portion 178 during removal of the inner catheter 34 and delivery of the stent (or balloon).

Referring to FIG. 9B, in an alternative embodiment of outer catheter 36, tapered portion 178 may be configured with an expandable tip scaffold 194, which is fabricated from NiTi wire and has a distal tip. It may be configured with a proximal end 196 and a proximal end 198 having a diameter greater than the diameter of the distal end 196 . Because of its flexibility, expandable scaffolding 194 expands and contracts as needed to resist permanent deformation of jacket 174 at tapered portion 178 during removal of the inner catheter and delivery of a stent or balloon member. provide additional support for

Another alternative embodiment of tapered portion 178 at the distal end of sheath 120 is shown in FIGS. 9C and 9D in which wall 180 of tapered portion 178 extends apart along its circumference. It is molded with a slit 200 extending longitudinally along its length. Slit 200 temporarily widens to receive distal tip 162 of inner catheter 34 when tapered portion 178 interfaces with the distal end of inner member 34 . This design can prevent permanent deformation of the jacket 174 at the tapered portion 178 that can be caused by removal of the inner catheter 34 or during stent/balloon delivery.

An important "seamless" aspect of the subject system is the transition between the outer diameter of the outer tip 164 of the sheath 120 (at its tapered portion 178) and the outer diameter of the distal tip 162 of the inner member 34. is to form a substantially gradual (smooth) transition between them.

As shown in FIGS. 2C, 10A-10G, 11A-11C, 12A-12C, 13A-13B, 14A-14B, and 15A-15D, the system of interest includes: an interconnection mechanism 220 including a proximal coupler 130 formed at the proximal end 132 of the sheath 120 of the outer member 36 at the intermediate portion 42 (FIGS. 17A and 17B, 18B, 19A and 19B, and FIG. and a cooperating feature 222 formed on the outer surface of inner member 34 (as shown in FIGS. 20A-20C).

The subject guide catheter extension/pre-dilatation system 10 can operate in an inner/outer catheter engagement mode and an inner/outer catheter disconnection mode, which is achieved by controlling the interconnection mechanism 220. The subject interconnection mechanism 220 engages/disengages the inner and outer catheters 34, 36 (as required in cardiac surgery) and prevents unwanted forward displacement of the inner member 34 inside the outer delivery sheath 120. is configured to prevent The engagement mode of operation is such that the connected push/pull element 134 of the outer member 36 is configured as a small profile flexible element (as flexible as or more flexible than the outer tubular sheath 120 of the outer catheter 36). It allows for improved "pushability" of the "whole system" (having the outer catheter 36 connected and locked to the inner catheter 34), even when the inner catheter 34 is closed.

The interconnection unit 220 is positioned at the proximal end 132 of the sheath 120 when the inner surface 152 of the tubular body 150 of the sheath 120 (at the proximal end 132) engages the outer surface 224 of the cooperating mechanism 222 (on the inner member 34). , and a cooperating feature 222 configured on the outer surface 224 of the inner member 34.

As an example, a number of interconnection mechanisms applicable to the subject guide catheter extension/pre-dilatation system 10 are envisioned. The subject engagement mechanism is configured for controllable engagement/disengagement between the inner member 34 and the outer member 36 as well as preventing forward movement of the inner member 34 relative to the outer delivery sheath 120 beyond a predetermined position. be done.

For example, as shown in FIGS. 11A-11C, laser-cut coupler 130 may include a proximal open (split) ring 240 and a pair of distal rings including a solid distal ring 242 and an open (split) distal ring 244 . It can be configured with a position ring. Proximal release ring 240 and distal rings 242 and 244 are integrally formed with coupler base 246 . Coupler 130 can be formed from stainless steel or heat-set NiTi. The pusher/puller element 134 and shift intermediate coupler (also referred to herein as the proximal coupler) 130 of the outer catheter 36 prevent deformation during antegrade or retrograde motion of the outer member and prevent stent (or other to prevent deformation of the mid-shaft coupler 130 as the catheter 130 passes through the mid-shaft portion of the outer catheter 36, it may be made of a memory metal (eg, nitinol, etc.).

The open ring 240 is correlated to the proximal inlet opening (eg, funnel-shaped) 211 of the outer catheter 36 (shown in FIGS. 10A, 10D, 10E, and 11C). Proximal release ring 240 allows expansion of entrance 211 to funnel 210 as required for entry/removal of inner catheter 34 as required in the surgical procedure. As shown in FIGS. 10A, 10D, 10E, and 11A-11C, a proximal release ring 240 provides support for the proximal opening 210 at the funnel-shaped proximal end of the seat 120. . Proximal ring 240 reinforces portal opening (“mouth”) 211 to prevent damage or permanent deformation of the portal opening and to support the elastic properties of sheath 120 at portal opening 210 . Distal rings 242 , 244 form a separate snap-fit locking mechanism from proximal release ring 240 of the funnel. Distal ring 242 does not expand (it is the outline of a closed circle), but the opening of split ring 244 expands upon displacement of inner catheter 34 relative to proximal coupler 130 of outer catheter 36 .

Base 246 of coupler 130 is flattened to match cooperating distal end 250 of pusher 134, which has either a flat or crescent (in the transverse direction) profile, as shown in FIGS. 11B and 11C. or preferably slightly arcuate (in cross section). Pusher 134 can be made from stainless steel or NiTi. Distal end 250 of pusher 134 is welded (glued, glued, or otherwise attached) to base member 246 of coupler 130 . A PTFE liner (also shown in FIG. 7) 172 may wrap the coupler 130 as shown in FIG. 11C.

A sheath 120 is disposed in a surrounding relationship between the coupler and the PTFE liner 172 . A Pebax encapsulation similar to distal soft tip jacket 174 at distal end 160 of sheath 120 (shown in FIG. 7) may be used at proximal end 132 of sheath 120 . A length of catheter shaft coil reinforcement 170 (also shown in FIG. 7) at the distal end of outer catheter 36 can extend to the proximal end of outer catheter 36 .

11A-11C, 17A-17C, and 18A-18B, the cooperating mechanism 222 for the particular embodiment shown in FIGS. Further includes a shaft mid-lock ring 252 (shown in FIGS. 17B, 17C, and 18B) for.

Another embodiment of the outer catheter proximal portal structure shown in FIGS. 12A-12C is similar to that shown in FIGS. 11A-11C, with certain modifications including the following.
(a) additional thickness and additional material around base 246 of coupler 130;
(b) a modified surface treatment (e.g., bead blasting) to improve adhesion of the polymer encapsulation; and (c) to provide additional support to the funnel to prevent damage that could impede passage of the stent. use of encapsulation with rigid polymers (such as nylon).

An additional embodiment of coupler 130 at proximal inlet 210 (shown in FIGS. 13A and 13B) features open rings (ribs) 256 that stiffen inlet port 210 . Snap-fit lock 260 is represented by at least two release rings 262 at the distal end of coupler 130 . Coupler 130 is preferably a laser cut coupler formed from either stainless steel or heat-set NiTi, as shown in the variations shown in FIGS. 13A and 13B.

Hypotube pusher/puller 134 may be flattened at its distal end 250 and welded to base 246 of coupler 130 . A PTFE liner 172 extends below the coupler 130 and a Pebax encapsulation 174 encases the coupler 130 to which the pusher 134 is attached. A catheter shaft coil reinforcement structure 170 extends along the shaft 120 of the outer catheter 36 from its distal end to its proximal end. A snap-fit lock 260 cooperates with the circular ring embodiment of cooperating mechanism 222 shown in FIGS. 17A-17C and 18B. In some embodiments, encapsulation 174 and/or pusher/puller 134 distinguish outer member pusher/puller 134 from other elements of the subject configuration for surgeon convenience and surgical safety. To that end, it may be color coated with a striking color, as shown in FIG. 11A.

A further variation of coupler 130 is shown in FIGS. 14A and 14B where coupler 130 has individual rings 266 , 268 welded to distal end 250 of pusher 134 . As shown, locking mechanism 260 is formed by a solid distal ring 266 and an intermediate split ring 268 , each ring 266 , 268 welded to pusher 134 . A proximal angled split ring 270 is also welded to pusher 134 . This design provides increased flexibility regarding the size and configuration of each ring 266, 268, and 270, allowing for a variety of funnel shapes/sizes as opposed to laser cut couplers which are limited to a single diameter. Support formation.

15A and 15B show another variation of proximal coupler 130 featuring a funnel window that improves contrast injection flow by providing additional open cross-sectional paths for fluid flow. A circular opening 272 is formed in the sheath 120 as shown in FIGS. 15A and 15B. The openings 272 are arranged in a predetermined pattern unobstructed by the proximal split ring 274 and distal rings 276 , 278 of the snap-fit locking structure 280 . As shown in FIGS. 15C and 15D, the coupler 130 has a triangular opening formed in the sheath 120 in an unobstructed manner by the proximal and distal rings 274, 278, 276 of the snap-fit lock 280. 282.

Although only circular and triangular openings 272, 282, respectively, are shown in FIGS. 15A-15D, other configurations of cutouts in the plastic encapsulation may be used to allow injected contrast fluid to pass through the cutouts. In addition, it is considered in the structure of interest.

16A, 16B, and 16C, another embodiment of the proximal end of the outer catheter 36 is shown, in which fluid and air are injected between the inner and outer catheters 34,36. It is specifically designed as a potential solution to prevent undesirable embolic situations in the event of accidental entry of To prevent this, a flush lumen 290 is incorporated into pusher 134 via flat hypotube. A luer hub is connected to the proximal end of the hypotube (pusher 134) as shown in FIG. As fluid enters the outer catheter lumen 292 through the channel 290 in the hypotube 134, air bubbles are prevented from entering between the inner and outer catheters.

17A-17C, between the proximal coupler 130 shown in FIGS. 11A-11E, 12A-12C, 13A-13B, 14A-14B, and 15A-15D. The interconnection unit 220 includes a cooperating member 222 in the form of an annular circular ring 252 (also referred to herein as an intermediate locking ring) formed on the outer surface 224 of the inner catheter 34 . The stainless steel annular ring 252 is contoured with a fully rounded surface that allows minimal reversible engagement/disengagement from the required split ring mechanism of the outer catheter coupler 130 . The ring 252 shown in FIG. 17C has rounded contours on the outer surface 302 for smooth locking/unlocking action. The inner surface 304 of ring 252 is also a smooth structure that engages the outer surface 224 of inner catheter 34 .

FIG. 17A shows a cut away configuration of inner catheter 34 relative to outer catheter 36 . FIG. 17B shows inner catheter 34 extending through opening 210 at the proximal end of sheath 120 such that ring 252 engages snap fit lock 306 formed by distal solid ring 308 and intermediate split ring 310 . Fig. 3 depicts the locking engagement configuration when received and locked inside; When in this position, the proximal angled split ring 312 surrounds the inner catheter 34 and the ring 252 is locked within the snap-fit lock 306, thus providing an inner catheter for surgical manipulation as required in surgery. and outer catheter are engaged.

Upon longitudinal movement of the inner catheter 34 inside the outer catheter 36, as the ring 252 passes through the proximal angled split ring 312 and the middle split ring 310, the arms of these rings are spread from their original position, Sufficient space is provided for passage of ring 252 . When in place, ie, when ring 252 is received between rings 308 and 310, the arms of angled split ring 312 and split ring 310 return to their original closed positions. Ring 252 is captured between rings 308, 310 and locked with a snap fit therebetween, thus preventing relative displacement of the inner and outer catheters.

18A and 18B detailing the structure shown in FIGS. 17A-17C, a portion (pocket) 316 of sheath 120 of outer catheter 36 is not reinforced by coil 170 and snap-fit lock 306 is Shown to flex when shaft intermediate locking ring 252 is inserted between solid distal ring 308 and intermediate split ring 310 . Flexible portion 316 of sheath 120 between rings 308 and 310 provides additional retention force to maintain inner catheter 34 and outer catheter 36 in locking engagement.

A stainless steel annular ring 252 can be attached to the outer surface 224 of the inner catheter shaft 34 by adhesive. The shape of the locking ring (perfectly circular surface) allows for smooth reversible engagement/disengagement with the laser cut features of the coupler 130 of the outer catheter. Distal ring 308 of snap-fit lock 306 prevents further distal movement of inner catheter 34 while intermediate split ring 310 opens upon contact with shaft intermediate locking ring 252 to provide a tactile snap. Proximal angled split ring 312 allows funnel 211 to open to an inner diameter that is larger than the inner diameter of the rest of shaft 120 . It also allows smooth passage of the shaft mid-lock ring 252 .

Interference between the non-reinforced shaft pocket 316 and the shaft mid-lock ring 252 causes the outer catheter 36 to remain locked until the user attempts to remove the inner catheter 34 from the outer catheter 36, thus disengaging the snap-fit lock between them. provide retention of the inner catheter 34 to the . The force required to disengage the locking mechanism can be adjusted from 0.1 to 2.0 pounds.

Referring to Figures 19A-19C, another alternative embodiment of a shaft midlock is shown that includes a square annular ring 320 (made of metal or polymeric material). Unlike ring 252 shown in FIGS. 17A-17C and 18B, ring 320 has a square cross section 321 shown in FIG. 19C. A square annular ring 320 is attached to the outer surface 224 of the inner catheter 34 using a heat-sealed Pebax encapsulation 322 . Alternatively, it may be glued to the outer surface 224 of the inner catheter. When the inner catheter is in the locked position, as shown in FIG. 19B, square annular ring 320 snaps into snap-fit lock 324 formed by solid ring 326 and split ring 328, encapsulation 322 sealing against the sheath. Ring 320 lies between rings 326 and 328 in contact with inner surface 152 of 120 .

In a further alternative embodiment shown in FIGS. 20A-20C, the shaft mid-locking mechanism 220 consists of two NiTi rings 332, 334 connected together via several (eg, four) NiTi shape setting wires 336. is formed with a cooperating member 222 in the form of a cage-like structure 330 having a . Cage 330 is attached to outer surface 224 of inner catheter 34 by either adhesive or heat-sealed Pebax encapsulation 338, as shown in FIG. 20A. Each of wires 336 has an arcuate extension 340 left free from encapsulation 338 as shown in FIGS. 20A and 20B.

In the locked configuration, cage structure 330 fits into outer catheter coupler 130, as shown in FIG. 20B. An unencapsulated arcuate portion 340 of each wire 336 extends outside of encapsulation 338 and away from wire 336 of cage 330 . When cage 330 is received between ring 342 and split ring 344 of snap-fit mechanism 346, locking mechanism 346 is activated and inner and outer catheters 34, 36 are engaged.

Still referring to FIG. 21, the proximal coupler 130 of the outer catheter 36 can include two locking slots 350, 352 formed by rings 354 and 356 connected by a connecting element 358. As shown in FIG.

17A-17C, 18A-18B, 19A-19B, 20A-20C, and 10A-10G, 11A-11C, 12A-12B, 13A-13B, FIGS. 14A and 14B, 15A-15D, and 21, when the surgeon linearly displaces inner member 34 within internal channel 122 of proximal coupler 130, snap-fit annular rings 252, 320, Or, cage 330 enters channel 122 between the arms of proximal rings 240, 312 that flex outward to allow forward movement of inner catheter 34 (towards distal tip 162). Further passage of the snap-fit annular ring 252, 320 or cage 330 through the intermediate split rings 244, 262, 268, 310, 328 of the snap-fit lock causes the arms of the angled proximal ring to return to their original positions, but not the intermediate ring. The arms of the split ring are flexed outward to allow the rings 252, 320 of the cage 330 to be positioned between the distal solid ring and the middle split ring. When the rings/cages 252, 320, 330 snap fit between the rings of the snap-fit locking mechanism, the arms of the middle split ring return to their original positions.

To disconnect inner member 34 from outer member 36 , the surgeon pulls inner member 34 from the inner channel of proximal coupler 130 . Upon removal of the snap-fit annular ring/cage 252, 320, 330 from the channel, the pulling action bends the arms of the intermediate split ring outwardly, causing the snap-fit annular ring/cage 252, 320, 330 to extend therebetween. Passage is allowed, thus releasing the inner catheter 34 from the proximal coupler 130 of the outer catheter 36 .

Returning to FIG. 3D , the inflation lumen distal shaft 66 of the intermediate portion 42 of the subject guide catheter/pre-dilatation extension system 10 can be manufactured with a braided reinforcement structure 260 . Braided reinforcement member 260 forms a somewhat flexible tube connected to cooperating features 222 of interconnection unit 220 of inner member 34 . A RX (rapid exchange) port 94 for passage of the guidewire 12 may be formed through the wall of the braid reinforced inflation lumen distal shaft 66 .

The braided reinforcement structure 260 may consist of metal patterns or wires within the braided reinforcement inflation lumen distal shaft 66 to prevent kinking that would otherwise impart longitudinal stiffness to the shaft 66 . A metal braid 260 may be embedded in the braid stiffening shaft 66 to add the high flexibility necessary for retraction of the inner member 34 relative to the outer delivery sheath 120 during surgery.

A rectangular wire spiral coil (eg, made from a shape memory alloy such as Nitinol) having a wire thickness of about 1 mil to 3 mils can be embedded in braid 260 . This coil can be formed with a very thin coating of plastic disposed on its inner and outer surfaces, which reduces the wall thickness of the inflation lumen distal shaft 66 to less than 7 mils, preferably about 5 mils. easier to reduce.

The principle of reinforcing a tubular member with a catheter shaft coil reinforcement 170 in the form of a flat wire helical coil 262 or forming a tubular member from a flat wire helical coil is applied in the subject guide catheter extension/pre-dilatation system 10 (FIGS. 7, 8B, 9A-9D, 10A, 11C, 12B and 12C, 13A and 13B, 14B, 15A-15C, 16A and 16B, 17A and 17B, 18A and outer delivery sheath 120 (as shown in FIGS. 2A and 2B, 5A, 22, and 24A-24B); It can be applied to microcatheter 46 . Such flat wire helical coils can be embedded in the outer delivery sheath 120 and/or the microcatheter 46 at predetermined locations along the length of their walls, such as the proximal and/or distal ends. .

Alternatively, the entire length of outer delivery sheath 120 and/or microcatheter 46 can be formed with a flat wire helical coil. The pitch between the coils is such that the gradient of flexibility along the length of the tubular member (sheath 120 and/or microcatheter 46) increases toward the distal end to facilitate atraumatic surgery. can be arranged to provide

22A-22B and 23A-23C, rather than utilizing a standard over-the-wire (OTW) guidewire lumen, a monorail rapid exchange (RX) design of the inner catheter 34' is implemented. , can allow the use of short guidewires. 22A and 22B, which represent an isometric view of the subject coil-reinforced inner member shaft 400 and a side view thereof taken along line AA, the distal portion 40 of the inner member 34'. ' includes tapered element 402 attached to outer surface 224 of inner member 34 . The outer shaft 400 of the inner member 34' is coil reinforced with a coil reinforcement structure 404 extending from the distal tip 406 to the RX inlet port 94 shown in FIGS. 2A-2C and 3C and 3D. Distal tip 406 is a tapered soft tip that, along with tapered element 402, interfaces with the inner surface of outer catheter 36 when inner catheter 34' is loaded within outer catheter 36 as required in a surgical procedure. .

Distal portion 40' includes a concentric guidewire lumen 408 that communicates with the RX entry port at the proximal end of inner catheter 34 (shown in Figures 2A-2C and Figures 3C and 3D).

As shown in FIGS. 23A-23C, the proximal end 412 of the embodiment of the monorail microcatheter shown in FIGS. 22A and 22B utilizes a milled hypotube pusher 414. The proximal end 412 of the coil reinforced inner member shaft 416 and the hypotube pusher 414 are shown in FIGS. 22A and 22B as tubes along the proximal end 412 of the monorail microcatheter embodiment of the inner member 34'. Encased within a proximal outer jacket 418 extending from (and including) member shaft 416 (functioning as guidewire lumen 408 ) and hypotube pusher 414 .

The embodiment shown in FIGS. 23A and 23B features an RX guidewire “notch” termination/entrance 420 manufactured by puncturing the proximal outer jacket 418 . Coil reinforced inner member shaft 416 is then inserted into proximal outer jacket tube 418 via RX entry “notch” 420 . Skived hypotube 415 is further inserted into proximal outer jacket tube 418 via its lumen 422 such that the polymer of coil reinforced inner member shaft 416 and proximal outer jacket tube 418 joins inner member shaft 416 and proximal outer jacket tube 418 . fused together to connect pusher 414, thus forming proximal end 412 of monorail microcatheter inner member 34'.

For the convenience of the surgeon, the push/pull element 134 of the outer catheter 36 may be replaced with other elements of the system, such as the push/pull element of the inner catheter 34, as well as the coronary guidewire or stent delivery used to deliver the device. It can be colored (color coated) as shown in FIG. 11A to have a distinctive color to distinguish it from the normal gray or silver color of the system. Alternatively, the proximal outer jacket 418 of the push/pull element 414 may be color coated such that its color distinguishes it from the colors of other elements in the system of interest.

24A and 24B, which depicts an inner catheter additional coil reinforced balloon catheter embodiment 500, this structure combines the reinforced shaft properties of the microcatheter 46 with the reinforced shaft properties of the expansion balloon 44 with the following attributes: Combine with
a. Coil reinforced shaft 502 provides additional kink resistance and pushability while still maintaining flexibility for navigating tortuous vasculature,
b. The longer distal tip 504 of the structure includes a tapered soft tip with a small profile to easily cross stenoses and narrow lesions.

As shown in FIGS. 24A and 24B, the distal portion 504 of the subject structure 500 includes an inner member shaft 500 reinforced with a coil reinforcement structure 506 extending the length of the inner member shaft 500 . A distal taper element 508 is disposed on inner member shaft 500 and extends between ends 510 and 512 in surrounding relationship to inner member shaft 500 . A distal tapered soft tip 514 may be in the form of microcatheter 46 disposed at the end of coil stiffened shaft 500 .

Similar to the embodiment shown in FIGS. 22A and 22B, balloon member 44 is positioned on inner member shaft 500 and radiopaque markers 264 and 266 are positioned on inner member shaft 500 within balloon member 44 . be done. At its proximal end 516 , balloon member 44 interferes with outer tip 164 of proximal tapered element 178 of outer member sheath 120 . At distal end 518 , balloon member 44 closely surrounds shaft 500 .

1-24B, in operation for performing cardiac surgery, particularly a predilation routine, the proximal end of coronary guidewire 12 is inserted into RX port 94 formed in inflation lumen distal shaft 66. and through the inner channel (GW lumen 96) of the inner member 34 to the outermost distal end 52 of the microcatheter 46 and extend past the outermost distal end 52 of the microcatheter 46. . A guide catheter 14 is then advanced into the vessel 16 of interest.

Subsequently, the outer delivery sheath 120 of the outer member 36, with the inner member 34 locked therein, is first placed within the inner channel 48 of the guide catheter 14, along with the microcatheter 46, and the inner and inner members as a single unit. Both outer members 34 , 36 are advanced together within guide catheter 14 toward treatment site 22 . Outer member sheath 120 and inner member 34 may be displaced together by pushing on outer member pusher 134 . This action causes the microcatheter 46 of the inner member 34 to slide along the GW 12 with the outer member 36 until it extends past the distal end 50 of the guide catheter 14 and reaches the lesion site 92 . At this stage of the procedure, balloon member 44 is in a deflated configuration.

A guidewire 12 extending past the distal end 50 of the guide catheter 14 is used to slide the microcatheter 46 (with the deflated balloon 44 attached to the distal tip 162) toward the treatment site 26. Act as a guide.

Balloon member 44 (located at treatment site 22 ) was subsequently formed by inflation lumen distal shaft 66 and inflation lumen hypotube 64 to compress plaque and open the blood passageway within vessel 16 . It is inflated by a balloon inflation system 62 connected to inflation hub 56 via an inflation lumen.

Subsequently, once the lesion is dilated, the balloon 44 can be deflated to advance the outer delivery sheath 120 across the lesion 22 as an integral unit with the inner member 34 (in the engagement mode of operation). , and thereafter the inner member can be disconnected (unlocked) from outer delivery sheath 120 and removed from sheath 120 .

Alternatively, the inner member 34 can be disconnected and withdrawn from the sheath 120 immediately after lesion expansion while the outer member 36 is advanced across the lesion 22 .

Sheath 120 may be left in place proximal to the treatment site (immediately after expansion of the lesion).

After pulling inner member 34, the stent can be delivered to site 22. FIG. The stent, in its closed configuration, can be introduced into vessel 16 inside sheath 120 . Once in place, a stent support balloon (not shown) can be inflated to open the stent. Outer delivery sheath 120 is then removed, leaving the stent open within vessel 16 .

Although the invention has been described with respect to specific forms and embodiments thereof, various modifications other than those described above may be made without departing from the spirit or scope of the invention as defined in the appended claims. You will understand that you can rely on it. For example, elements specifically shown and described may be replaced with functionally equivalent elements, certain features may be used independently of other features, and in certain cases, elements may be Certain positions, steps, or processes allow reversals or interventions, none of which depart from the spirit or scope of the invention as defined in the appended claims.

Claims (23)

An intravascular delivery device having a proximal portion, a distal portion, and an intermediate portion located between the proximal portion and the intermediate portion and configured to be controllably displaced within a vessel of interest. input system,
formed by a flexible, substantially cylindrically contoured elongated outer delivery sheath defining a sheath lumen having proximal and distal ends, said outer delivery sheath being connected to said intermediate portion; an outer member extending between a distal portion and configured with a tapered outer tip at the distal end of the sheath lumen;
The tapered outer tip of the outer member at the distal end of the outer delivery sheath is cylindrically shaped between distal and proximal edges of the tapered outer tip. An extending wall having an inner diameter and an outer diameter, the inner diameter and outer diameter of the wall extending from the proximal edge to the distal edge of the tapered outer tip. an outer member gradually decreasing in a direction toward the portion;
It has an elongated body defining an interior channel extending along a longitudinal axis and extends along the inside of the sheath lumen of the outer member in controllable relationship with the outer delivery sheath. an inner member,
The elongated body of the inner member has an outer diameter and has a tapered distal portion configured with a tapered delivery catheter having an elongated body of a predetermined length, the tapered A shaped delivery catheter is displaceable past the distal end of the sheath and the wall of the tapered outer tip of the outer member at least temporarily displaces the distal end of the inner member. said wall of said tapered outer tip of said outer member at said interface between said wall of said tapered outer tip of said outer member and said distal portion of said inner member. wherein the inner diameter of the inner member is less than the outer diameter of the distal portion of the inner member;
an interconnection mechanism disposed in operative association with the inner and outer members and controllably actuated to operate the guide catheter extension/pre-dilatation subsystem in an engaged mode of operation or a disengaged mode of operation;
and
In the engaged mode of operation, the inner and outer members of the guide catheter extension subsystem engage for controllable displacement together along a guidewire, the inner member, when engaged, the outer It cannot be displaced independently with respect to the member,
The intravascular delivery system wherein, in the decoupled mode of operation, the inner and outer members are separated to retract the inner member from the outer member. the tapered distal portion of the inner member interfaces on its outer surface with the inner surface of the tapered outer tip of the sheath lumen;
the tapered outer tip of the outer member is an elastomeric tapered outer tip;
wherein, in the separation mode of operation, the inner diameter of the wall of the tapered outer tip of the outer member is less than the outer diameter of the inner member;
In the engaged mode of operation, the dimensional transition between the outer diameter of the tapered outer tip of the sheath lumen and the outer diameter of the distal portion of the inner member is substantially 3. The intravascular system of claim 1, wherein the tapered outer tip of the outer member and the inner member interact to form a stepless interface. said sheath being reinforced along its length, said outer member further comprising at its distal end a distal soft tip encapsulant encapsulating said reinforced sheath of said outer member; 2. The system of claim 1, wherein the soft tip encapsulating material is a flexible low durometer elastomeric material having a durometer value with an increasing gradient from the distal end to the proximal end of the sheath. 4. The system of claim 3, wherein the outer member further comprises a distal lubricating liner sandwiched between an outer surface of the sheath and an inner surface of the distal soft tip encapsulant. the delivery catheter is a microcatheter;
a balloon member attached to the tapered distal portion of the inner member proximate the tapered delivery microcatheter;
an inflation lumen extending within the inner member between the proximal portion and the balloon member of the distal portion to provide a fluid passageway between an external balloon inflation system and the balloon member; 2. The system of claim 1, further comprising: 6. The intravascular system of Claim 5, wherein the balloon member has a proximal portion having a proximal diameter greater than a distal outer diameter at its distal portion. The balloon member assumes an inflated state and a deflated state, wherein in the deflated state the balloon member is displaced within the vessel and the balloon member is positioned at least in alignment with a treatment site for a pre-dilatation procedure. 6. The intravascular system of claim 5, wherein the endovascular system is controllably changed to the inflated state after the expansion. The elongate body of the inner member and the microcatheter were reinforced with a coil along their length, and the tapered distal portion of the inner member was disposed on the coil reinforced elongate body. 6. The system of claim 5, comprising a distal taper element. The outer delivery sheath of the outer member has a tubular body having a first predetermined perimeter, the tubular body of the outer member extending from the tapered outer side of the distal end of the outer delivery sheath. Extending between a distal end and said proximal end, at said proximal end said outer delivery sheath is configured with an inlet opening having a second predetermined circumference, said inlet opening 3. The system of claim 2, wherein the second predetermined perimeter of exceeds the first perimeter of the tubular body of the outer delivery sheath. The tapered outer tip of the outer member has a resiliently expandable configuration and the inlet opening at the proximal end of the outer sheath is funnel-shaped. 10. The system according to Item 9. an outer member pusher configured with a flattened portion at a distal end and secured to the proximal end of the sheath of the outer member;
3. The intravascular system of claim 2, wherein the outer member pusher is configured with a channel extending along its length, the channel communicating with the sheath lumen. The outer sheath of the outer member is a flexible sheath having a first flexibility along its length and the outer member pusher has a second flexibility along its length. 12. The intravascular system of Claim 11, wherein the flexible member is a flexible member and the second flexibility is substantially the same as or exceeds the first flexibility. The interconnection mechanism includes a snap-fit mechanism, the snap-fit mechanism disposed on the outer surface of the elongated body of the inner member and a proximal coupler disposed at the proximal end of the sheath of the outer member. wherein the proximal coupler includes a distal solid ring and an intermediate split ring positioned a predetermined distance from the solid ring, the cooperating member comprising: a member selected from the group comprising a shaft mid-lock ring, a square annular ring, and a snap-fit cage, said cooperating member attached to said outer surface of said elongated body of said inner member; 2. The intravascular system of claim 1, wherein the members are releasably locked in a snap-fit manner between the distal solid ring and the intermediate split ring for engaging members. 14. The vessel of claim 13, wherein the cooperating member is secured to the outer surface of the inner member in surrounding relationship and the proximal coupler further includes a proximal angled split ring at its proximal end. internal system. 15. The system of claim 14, further comprising a window system formed in said sheath at its proximal end. 4. The microcatheter is formed of a flexible material having differential flexibility along its length, the flexibility of the microcatheter increasing toward its distal end. 6. The intravascular system according to 5. The microcatheter includes a flat wire helical coil extending along the predetermined length of the microcatheter, the pitch of the flat wire helical coil being such that the flexibility of the microcatheter increases toward its distal end. 17. The intravascular system of claim 16, wherein the length varies along the length of the microcatheter such that: a flat wire helical coil member forming at least a portion of a wall of each of a member selected from the group comprising: said outer delivery sheath of said outer member; said delivery catheter; said elongated body of said inner member; and combinations thereof. 2. The intravascular system of claim 1, further comprising: wherein the flat wire helical coil is formed of a shape memory alloy such as Nitinol or is formed of a radiopaque material. the tapered delivery catheter structure is a microcatheter formed with a longitudinally extending lumen for sliding over a guidewire;
an inner member pusher coupled at its distal end to the proximal end of the inner member;
an outer member pusher coupled at its distal end to the proximal end of the outer member;
3. The intravascular system of claim 1, wherein the outer member pusher is color coated, the color coating having a color distinguishable from the guidewire color and the inner member and inner member pusher colors. An intravascular system comprising a guide catheter extension subsystem cooperating with a guidewire, comprising:
a guide catheter extension subsystem having a proximal portion, a distal portion, and an intermediate coupling portion interconnected between the proximal and distal portions;
The guide catheter extension subsystem includes:
an outer member formed by a flexible, substantially cylindrically contoured elongated sheath having a stiffening structure along said sheath, said sheath extending from a proximal end and a distal end; defining a sheath lumen having a proximal end, the sheath extending between the intermediate connecting portion and the distal portion of the guide catheter extension subsystem, the outer member distal of the sheath lumen; a cylinder having a distal soft-elastic tip disposed at an end, said distal soft-elastic tip having a thickness decreasing from a proximal edge to a distal edge of said distal soft-elastic tip; an outer member configured with a shaped wall, said wall having an inner diameter at said distal edge;
an inner member having a coil reinforced elongated body defining an interior channel extending along a longitudinal axis, said inner member being positioned in said sheath lumen in controllably displaceable relationship with said sheath; said inner member having a tapered distal portion of said distal end configured with a tapered delivery catheter structure; said tapered distal portion of said inner member; The posterior portion has an elongated body reinforced with a length of coil, the elongated body of the inner member having an outer diameter exceeding the inner diameter of the wall of the distal soft elastic tip of the outer member. wherein the tapered distal portion of the inner member resiliently interfaces at its outer surface with the inner surface of the distal soft resilient tip of the sheath, the tapered delivery catheter structure comprising: an inner member displaceable past the distal end of the sheath;
disposed in operative association with the inner and outer members of the guide catheter extension subsystem for controllably actuating the guide catheter extension subsystem to intermittently operate in an engagement mode or a disengagement mode of operation; wherein in the engaged mode of operation the outer surface of the tapered distal tip of the inner member and the outer surface of the wall of the distal soft resilient tip of the outer member are both and an interconnection mechanism that forms a substantially smooth transition between
In the engaged mode of operation, the inner and outer members of the guide catheter extension subsystem are engaged for controllable displacement together along a guidewire;
An intravascular system wherein, in the decoupled mode of operation, the inner and outer members are decoupled for controllable individual linear or rotational displacement relative to each other. The sheath is configured at its proximal end with an inlet opening having a perimeter that exceeds the outer perimeter of the tubular body of the sheath, the inlet opening being an angled split mounted adjacent to the inlet opening. 21. The system of claim 20, reinforced by ring elements. further comprising a guidewire capable of being advanced within the subject's vessel to at least the treatment site;
the guide catheter extension subsystem configured to be controllably displaced along the guidewire;
an inner member pusher coupled at its distal end to the proximal end of the inner member;
an outer member pusher coupled at its distal end to the proximal end of the outer member;
an elastic jacket enclosing the inner member at least at the proximal end thereof and the inner member pusher along at least the distal end thereof;
21. The intravascular system of Claim 20, wherein the tapered delivery catheter structure is a microcatheter formed with a longitudinally extending lumen for sliding over the guidewire. 23. The vessel of claim 22, wherein the outer member pusher is color coated, the color coating having a color distinguishable from the color of the guidewire and the color of the elastic jacket encasing the inner member and the inner member pusher. internal system.

Images