CN118266932A

CN118266932A - Fractal cylindrical cage system and method for distributed tissue contact for mapping and ablation

Info

Publication number: CN118266932A
Application number: CN202311830032.XA
Authority: CN
Inventors: J·罗德里格斯苏涂; M·阿巴斯; B·易卜拉希米; P·E·范尼克; S·巴苏
Original assignee: Biosense Webster Israel Ltd
Current assignee: Biosense Webster Israel Ltd
Priority date: 2022-12-29
Filing date: 2023-12-28
Publication date: 2024-07-02

Abstract

The present invention relates to fractal cylindrical cage systems and methods for distributed tissue contact for mapping and ablation. The disclosed technology includes a medical probe including a plurality of spine members forming a generally cylindrical structure. Each ridge is stamped from a continuous sheet of flat stock material and heat treated to a configuration including a first section extending along a longitudinal axis from a first end to a first bend, a second section extending from the first section curvedly relative to the longitudinal axis and including a bifurcation point, and a third section extending along the longitudinal axis from a second bend to a second end such that a proximal portion of the third section is substantially parallel to the first section. The second section includes a continuous leg and a discontinuous leg. The continuous leg extends between the first section and the bifurcation point. The discontinuous leg extends toward the first section and terminates at a termination point between the bifurcation point and the first end.

Description

Fractal cylindrical cage system and method for distributed tissue contact for mapping and ablation

Cross Reference to Related Applications

The present application claims the benefit of priority from U.S. c. ≡119 to U.S. provisional patent application No. 63/477,800, filed on even 29 days of 2022, 12, the entire contents of which provisional patent application is hereby incorporated by reference as if fully set forth herein.

Technical Field

The present invention relates generally to medical devices, and in particular to catheters having electrodes, and further but not exclusively to catheters suitable for mapping, ablating, or inducing irreversible electroporation (IRE) of cardiac tissue and pulmonary veins.

Background

Electrophysiology catheters are commonly used to map the electrical activity of the heart or induce ablation of regions of heart tissue to stop or alter the propagation of unwanted electrical signals from one portion of the heart to another. Many electrophysiology catheters have basket electrode arrays. In particular, catheters having basket electrode arrays are known and described, for example, in U.S. patent 5,772,590, 6,748,255, and 6,973,340, each of which is incorporated herein by reference and attached in the appendix of priority application U.S.63/477,800. Some ablation methods use irreversible electroporation (IRE) to ablate cardiac tissue using non-thermal ablation methods. IRE delivers short pulses of high pressure to the tissue and produces unrecoverable cell membrane permeabilization. The use of multi-electrode catheters to deliver ablation or irreversible electroporation (IRE) energy to tissue has previously been proposed in the patent literature. Examples of systems and devices configured for IRE ablation are disclosed in U.S. patent publications 2021/0169550A1 (now U.S. patent No. 11,660,135), 2021/0169567A1, 2021/0169568A1, 2021/0161592A1 (now U.S. patent No. 11,540,877), 2021/0196372A1, 2021/0177503A1, and 2021/0186604A1 (now U.S. patent No. 11,707,320), each of which is incorporated herein by reference and attached to the appendix of priority application u.s.63/477,800.

Areas of cardiac tissue may be mapped through the catheter to identify abnormal electrical signals. Ablation may be performed using the same or different catheters. Some example catheters include a plurality of ridges on which electrodes are disposed. The electrodes are typically attached to the ridges and secured in place by brazing, welding, or using an adhesive. Further, the plurality of linear ridges are typically assembled together to form a ball basket by attaching both ends of the linear ridges to a tubular shaft (e.g., a pusher tube). The ball basket assembly is capable of detecting the electrical function of the left atrium or the right atrium. However, because the cross-section of the pulmonary vein is generally not perfectly circular but rather more elliptical, a generally cylindrical assembly with a planar electrode array may provide for more uniform detection of the electrical function of cardiac tissue at or near the pulmonary vein. However, due to the smaller size of the ridges and electrodes, adhering the electrodes to the ridges, and then forming the ball basket from multiple linear ridges can be a difficult task, increasing manufacturing time and cost, and increasing the chance of failure of the electrodes due to improper bonding or misalignment. Accordingly, what is needed are devices and methods of forming improved medical probes that generally can help reduce the time required for manufacturing and alternative catheter geometries.

Disclosure of Invention

Various embodiments of a medical probe and related methods are described and illustrated. The present disclosure includes a structural unit for a medical probe that includes a spine member having a first section extending along a longitudinal axis from a first end to a first bend, a second section extending from the first section curvedly relative to the longitudinal axis, and a third section extending along the longitudinal axis from a second bend to a second end such that a proximal portion of the third section is substantially parallel to the first section. The second section may include a bifurcation point.

The medical probe may include a generally cylindrical structure formed from a plurality of spine members disposed about a longitudinal axis and a plurality of electrodes. Each of the plurality of spine members may include a first section extending from the first end to the first bend along the longitudinal axis, a second section extending from the first section curvedly relative to the longitudinal axis, and a third section extending from the second bend to the second end along the longitudinal axis such that a proximal portion of the third section is substantially parallel to the first section. The second section may include a bifurcation point. A plurality of electrodes may be coupled to each of the plurality of spine members.

The present disclosure includes a medical probe that may include a generally cylindrical structure. The generally cylindrical structure may include a plurality of discrete ridge members. Each spine member may include a distal bend, a middle portion, and a first spine end. A plurality of spine members may be disposed together at the distal end of the generally cylindrical structure at each respective distal bend. The plurality of spine members may also be disposed at a proximal end of the generally cylindrical structure at each respective first spine end. Each respective intermediate portion may be axially bent from the longitudinal axis to form an outer surface of the generally cylindrical structure.

The present disclosure includes a method of constructing a medical probe. The method may include stamping a plurality of spine members from a continuous flat stock material, heat treating the plurality of spine members such that each spine member forms a configuration, and aligning distal bends of at least four spine members to define a generally cylindrical structure. Each of the plurality of spine members may include a first section extending from the first end to the first bend along the longitudinal axis, a second section extending from the first section curvedly relative to the longitudinal axis, and a third section extending from the second bend to the second end along the longitudinal axis such that a proximal portion of the third section is substantially parallel to the first section. The second section may include a bifurcation point.

The present disclosure includes a method of constructing a medical probe. The method may include fabricating one or more electrical traces on the film, aligning one or more electrodes within the one or more electrical traces, and positioning the film over a plurality of discrete ridge members shaped to form a generally cylindrical structure.

Drawings

FIG. 1 is a schematic illustration of a medical system including a medical probe having a distal end with a fractal, generally cylindrical structure with electrodes, according to an embodiment of the present invention;

FIG. 2A is a schematic illustration showing a perspective view of a medical probe in an expanded form according to an embodiment of the invention;

FIG. 2B is a schematic illustration showing a side view of a medical probe in a collapsed form according to an embodiment of the invention;

FIG. 3 is a schematic illustration showing an exploded side view of a medical probe according to an embodiment of the present invention;

FIG. 4A is a schematic illustration of a spine member stretched into a linear configuration according to an embodiment of the present invention;

FIGS. 4B and 4C are schematic illustrations showing side views of the spine member of FIG. 4A in various heat treatment configurations in accordance with embodiments of the present invention;

Fig. 5A and 5B are schematic illustrations showing a side view (fig. 5A) and a top view (fig. 5B) of two adjacent ridge members having different bifurcation points according to an embodiment of the present invention;

fig. 6 is a schematic illustration showing a perspective view of a generally cylindrical structure having a fractal ridge member in an expanded form in accordance with an embodiment of the present invention;

Fig. 7A is a schematic illustration showing a perspective view of a generally cylindrical structure having a fractal ridge member in an expanded form in accordance with an embodiment of the present invention;

FIG. 7B is a schematic illustration showing a side view of the ridge member of FIG. 7A, in accordance with an embodiment of the invention;

Fig. 8A and 8B are schematic illustrations showing perspective views of various exemplary membranes having electrodes according to embodiments of the present invention;

FIG. 8C is a schematic illustration showing a close-up of electrodes and electrical traces on the film of FIG. 8B, according to an embodiment of the invention;

FIG. 9 is a flow chart illustrating another method of assembling a medical probe according to an embodiment of the present invention; and

Fig. 10 is a flow chart illustrating another method of assembling a medical probe according to an embodiment of the present invention.

Detailed Description

The following detailed description should be read with reference to the drawings, in which like elements in different drawings are numbered identically. The drawings, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of the invention. The detailed description illustrates by way of example, and not by way of limitation, the principles of the invention. This description will clearly enable one skilled in the art to make and use the invention, and describes several embodiments, adaptations, variations, alternatives and uses of the invention, including what is presently believed to be the best mode of carrying out the invention.

As used herein, the term "about" or "approximately" for any numerical value or range indicates a suitable dimensional tolerance that allows a collection of parts or components to achieve the intended purpose thereof as described herein. More specifically, "about" or "approximately" may refer to a range of values of ±20% of the recited values, for example "about 90%" may refer to a range of values of 71% to 110%.

As used herein, the terms "patient," "subject," "user," and "subject" refer to any human or animal subject, and are not intended to limit the system or method to human use, but use of the subject invention in a human patient represents a preferred embodiment. Furthermore, the vasculature of a "patient," "subject," "user," and "subject" may be that of a human or any animal. It should be understood that the animal may be of any suitable type including, but not limited to, a mammal, a veterinary animal, a livestock animal or a companion animal, and the like. For example, the animal may be a laboratory animal (e.g., rat, dog, pig, monkey, etc.) specifically selected to have certain characteristics similar to humans. It should be appreciated that the subject may be, for example, any suitable human patient. Likewise, the term "proximal" refers to a location closer to an operator or physician, while "distal" refers to a location further from the operator or physician.

As discussed herein, a "physician" may include a doctor, surgeon, technician, scientist, operator, or any other individual or delivery meter device associated with delivering a multi-electrode catheter for treating drug refractory atrial fibrillation to a subject.

As discussed herein, when referring to the devices and corresponding systems of the present disclosure, the term "ablation" refers to components and structural features configured to reduce or prevent the generation of unstable cardiac signals in cells by utilizing non-thermal energy, such as irreversible electroporation (IRE), interchangeably referred to in the present disclosure as Pulsed Electric Field (PEF) and Pulsed Field Ablation (PFA). "ablation" as used throughout the present disclosure, when referring to the devices and corresponding systems of the present disclosure, refers to non-thermal ablation of cardiac tissue for certain conditions, including, but not limited to, arrhythmia, atrial flutter ablation, pulmonary vein isolation, supraventricular tachycardia ablation, and ventricular tachycardia ablation. The term "ablation" also includes known methods, devices and systems for effecting various forms of ablation of body tissue as understood by those skilled in the relevant art.

As discussed herein, the terms "bipolar" and "monopolar" when used in reference to an ablation scheme describe an ablation scheme that differs in terms of current path and electric field distribution. "bipolar" refers to an ablation protocol that utilizes a current path between two electrodes, both of which are positioned at a treatment site; the current density and the current flux density at each of the two electrodes are typically approximately equal. "monopolar" refers to an ablation procedure utilizing a current path between two electrodes, wherein one electrode comprising a high current density and a high electrical flux density is positioned at the treatment site and a second electrode comprising a relatively lower current density and a lower electrical flux density is positioned away from the treatment site.

As discussed herein, the terms "biphasic pulse" and "monophasic pulse" refer to the corresponding electrical signals. A "biphasic pulse" refers to an electrical signal comprising a positive voltage phase pulse (referred to herein as a "positive phase") and a negative voltage phase pulse (referred to herein as a "negative phase"). "monophasic pulse" refers to an electrical signal that includes only a positive or negative phase. Preferably, the system providing biphasic pulses is configured to prevent the application of a direct current voltage (DC) to the patient. For example, the average voltage of the biphasic pulse may be zero volts relative to ground or other common reference voltage. Additionally or alternatively, the system may include a capacitor or other protective component. Voltage amplitudes of biphasic and/or monophasic pulses are described herein, it being understood that the expressed voltage amplitudes are absolute values of the approximate peak amplitudes of each of the positive voltage phase and/or the negative voltage phase. Each phase of the biphasic pulse and the monophasic pulse preferably has a square shape that includes a substantially constant voltage amplitude during most of the phase's duration. The phases of the biphasic pulse are separated in time by an inter-phase delay. The inter-phase delay duration is preferably less than or approximately equal to the duration of the phase of the biphasic pulse. The inter-phase delay duration is more preferably about 25% of the duration of the phase of the biphasic pulse.

As discussed herein, the terms "tubular" and "tube" are to be understood in a broad sense and are not limited to structures that are right circular cylinders or that are entirely circumferential in cross-section or have a uniform cross-section throughout their length. For example, the tubular structure is generally shown as a substantially right circular cylinder structure. However, the tubular structure may have a tapered or curved outer surface without departing from the scope of the present disclosure.

As used herein, the term "temperature rating" is defined as the maximum continuous temperature that a component can withstand during its lifetime without causing thermal damage such as melting or thermal degradation (e.g., charring and chipping) of the component.

The present disclosure relates to systems, methods, or uses and devices utilizing an end effector that includes an electrode attached to a membrane positioned over a spine. The exemplary systems, methods, and devices of the present disclosure may be particularly useful for mapping and IRE ablation of cardiac tissue to treat cardiac arrhythmias. Ablation energy is typically provided to the heart tissue by an end portion of the catheter that can deliver ablation energy along the tissue to be ablated. Some example catheters include a three-dimensional structure at the tip portion and are configured to apply ablation energy from various electrodes positioned on the three-dimensional structure. Fluoroscopy may be used to visualize the ablation procedure in combination with such exemplary catheters.

Cardiac tissue ablation using thermal techniques such as Radio Frequency (RF) energy and cryoablation to correct for a malfunctioning heart is a well-known procedure. Typically, for successful ablation using thermal techniques, the cardiac electrode potentials need to be measured at various locations in the myocardium. Furthermore, temperature measurements during ablation provide data that enables ablation efficacy. Typically, for ablation protocols using thermal ablation, electrode potential and temperature are measured before, during, and after the actual ablation.

RF methods may have risks that may lead to charring of tissue, burns, steam bursts, phrenic nerve paralysis, pulmonary vein stenosis, and esophageal fistulae. Cryoablation is an alternative to RF ablation, which may reduce some of the thermal risks associated with RF ablation. However, manipulating a cryoablation device and selectively applying cryoablation is generally more challenging than RF ablation; thus, cryoablation is not feasible in certain anatomical geometries that may be reached by an electrical ablation device.

IRE as discussed in this disclosure is a non-thermal cell death technique that may be used for atrial arrhythmia ablation. To ablate using IRE/PEF, biphasic voltage pulses are applied to disrupt the cellular structure of the myocardium. The biphasic pulse is non-sinusoidal and can be tuned to target cells based on the electrophysiology of the cells. In contrast, to ablate using RF, a sinusoidal voltage waveform is applied to generate heat at the treatment region, heating all cells indiscriminately in the treatment region. Thus, IRE has the ability to avoid adjacent heat sensitive structures or tissue, which would be beneficial in reducing the possible complications known to be affected by ablation or separation modalities. In addition or alternatively, monophasic pulses may be used.

Electroporation can be induced by applying a pulsed electric field across the biological cells to cause reversible (temporary) or irreversible (permanent) creation of pores in the cell membrane. Upon application of a pulsed electric field, the cell has a transmembrane electrostatic potential that rises above the static potential. Electroporation is reversible when the transmembrane electrostatic potential remains below the threshold potential, meaning that the pores can close when the applied pulsed electric field is removed and the cells can repair and survive themselves. If the transmembrane electrostatic potential rises above the threshold potential, electroporation is irreversible and the cell becomes permanently permeable. Thus, cells die from a loss of homeostasis, typically from programmed cell death or apoptosis, which is believed to leave less scar tissue than other modes of ablation. Typically, different types of cells have different threshold potentials. For example, cardiac cells have a threshold potential of about 500V/cm, whereas for bone, the threshold potential is 3000V/cm. These differences in threshold potential allow IRE to selectively target tissue based on the threshold potential.

The solutions of the present disclosure include systems and methods for applying electrical signals from catheter electrodes positioned near myocardial tissue, preferably by applying a pulsed electric field effective to induce electroporation in myocardial tissue. The systems and methods can effectively ablate targeted tissue by inducing irreversible electroporation. In some examples, the systems and methods are effective to induce reversible electroporation as part of a diagnostic procedure. Reversible electroporation occurs when the electricity applied with the electrodes is below the electric field threshold of the target tissue that allows cell repair. Reversible electroporation does not kill cells, but allows the physician to view the effect of reversible electroporation on the electrical activation signal near the target site. Exemplary systems and methods for reversible electroporation are disclosed in U.S. patent publication 2021/0162210, the entire contents of which are incorporated herein by reference and attached to the appendix of priority application U.S.63/477,800.

The pulsed electric field and its effectiveness in inducing reversible and/or irreversible electroporation may be affected by the physical parameters of the system and the biphasic pulse parameters of the electrical signal. Physical parameters may include electrode contact area, electrode spacing, electrode geometry, and the like. Examples presented herein generally include physical parameters suitable for effectively inducing reversible and/or irreversible electroporation. Biphasic pulse parameters of an electrical signal may include voltage amplitude, pulse duration, pulse-to-pulse delay, inter-pulse delay, total applied time, delivered energy, and the like. In some examples, parameters of the electrical signal may be adjusted to induce both reversible and irreversible electroporation given the same physical parameters. Examples of various ablation systems and methods including IRE are disclosed in U.S. patent publications 2021/0169550A1 (now U.S. patent 11,660,135), 2021/0169567A1, 2021/0169568A1, 2021/0161592A1 (now U.S. patent 11,540,877), 2021/0196372A1, 2021/0177503A1, and 2021/0186604A1 (now U.S. patent 11,707,320), the entire contents of each of these patent publications being incorporated herein by reference and attached to the appendix of priority application u.s.63/477,800.

To deliver Pulsed Field Ablation (PFA) in an IRE (irreversible electroporation) procedure, the surface area of the electrode in contact with the tissue being ablated should be sufficiently large. As described below, the medical probe includes a plurality of spine members disposed about a longitudinal axis and a plurality of electrodes coupled to each of the plurality of spine members, the plurality of spine members defining a generally cylindrical shape. Each spine member includes a first section extending along the longitudinal axis from the first end to the first bend, a second section extending curvingly from the first section relative to the longitudinal axis and having a bifurcation point, and a third section extending along the longitudinal axis from the second bend to the second end such that a proximal portion of the third section is substantially parallel to the first section.

The medical probe also has a membrane surrounding the plurality of spine members, the membrane defining an interior volume of the medical probe. The membrane includes one or more external electrodes disposed on an outer surface of the membrane and an internal electrode disposed on an inner surface of the membrane. The membrane has a plurality of apertures that allow fluid communication from outside the membrane to the interior volume.

Referring to fig. 1, an exemplary catheter-based electrophysiology mapping and ablation system 10 is shown. The system 10 includes a plurality of catheters that are percutaneously inserted by a physician 24 into a chamber or vascular structure of the heart 12 through the vascular system of a patient 23. Typically, the delivery sheath catheter is inserted into the left atrium or the right atrium near the desired location in the heart 12. A plurality of catheters may then be inserted into the delivery sheath catheter in order to reach the desired location. The plurality of catheters may include catheters dedicated to sensing Intracardiac Electrogram (IEGM) signals, catheters dedicated to ablation, and/or catheters dedicated to both sensing and ablation. An exemplary catheter 14 configured for sensing IEGM is shown herein. The physician 24 brings the distal tip 28 of the catheter 14 including the medical probe 16 into contact with the heart wall at or near the pulmonary vein for sensing a target site in the heart 12. For ablation, the physician 24 would similarly bring the distal end of the ablation catheter including the medical probe 16 to the target site to perform the ablation.

The medical probe 16 is an exemplary probe that includes one and preferably a plurality of electrodes 26 optionally distributed over a plurality of ridges 22 at a distal tip 28 and configured to sense IEGM signals. The medical probe 16 may additionally include a position sensor 29 embedded in or near the distal tip 28 for tracking the position and orientation of the distal tip 28. Optionally and preferably, the position sensor 29 is a magnetic-based position sensor comprising three magnetic coils for sensing three-dimensional (3D) position and orientation. As shown in more detail in fig. 2A, medical probe 16 may include a membrane 70 positioned over the plurality of spine members 22. The position sensor 29 may be a conventional wire-wound sensor, a flat PCB-based sensor, or a deformable electromagnetic ring sensor. Although not depicted, the position sensor 29 may alternatively be positioned on the basket assembly 28 or designed into each spine 22. In some embodiments, each ridge 22 may be insulated and act as a position sensor.

In some embodiments, medical probe 16 may include a deformable electromagnetic ring sensor. Examples of various systems and methods for deformable electromagnetic ring sensors are given in U.S. patent 11,304,642 and 10,330,742 and U.S. patent publications 2018/0344202A1 and 2020/0155224A1, each of which is incorporated herein by reference and attached in the appendix of priority application u.s.63/477,800.

The magnetic-based position sensor 29 is operable with a placemat 25 that includes a plurality of magnetic coils 32 configured to generate a magnetic field in a predetermined workspace. The real-time position of the distal tip 28 of the catheter 14 may be tracked based on the magnetic field generated with the location pad 25 and sensed by the magnetic-based position sensor 29. Details of magnetic-based position sensing techniques are described in U.S. patent No. 5,391,199、5,443,489、5,558,091、6,172,499、6,239,724、6,332,089、6,484,118、6,618,612、6,690,963、6,788,967、6,892,091, each of which is incorporated herein by reference and attached in the appendix of priority application U.S.63/477,800.

The system 10 includes one or more electrode patches 38 that are positioned in contact with the skin of the patient 23 to establish a positional reference for impedance-based tracking of the location pad 25 and the electrode 26. For impedance-based tracking, current is directed toward the electrodes 26 and sensed at the electrode skin patches 38 so that the position of each electrode can be triangulated via the electrode patches 38. Details of impedance-based location tracking techniques are described in U.S. patent nos. 7,536,218, 7,756,576, 7,848,787, 7,869,865, and 8,456,182, each of which is incorporated herein by reference and attached in the appendix of priority application u.s.63/477,800.

Recorder 11 displays an electrogram 21 captured with body surface ECG electrodes 18 and an Intracardiac Electrogram (IEGM) captured with electrodes 26 of catheter 14. Recorder 11 may include pacing capabilities for pacing the heart rhythm and/or may be electrically connected to a separate pacemaker.

The system 10 may include an ablation energy generator 50 adapted to conduct ablation energy to one or more electrodes at a distal tip of a catheter configured for ablation. The energy generated by ablation energy generator 50 may include, but is not limited to, radio Frequency (RF) energy or Pulsed Field Ablation (PFA) energy, including monopolar or bipolar high voltage DC pulses that may be used to achieve irreversible electroporation (IRE), or a combination thereof.

The Patient Interface Unit (PIU) 30 is an interface configured to establish electrical communication between a catheter, electrophysiological equipment, a power source, and a workstation 55 for controlling operation of the system 10. The electrophysiological equipment of system 10 can include, for example, a plurality of catheters, location pads 25, body surface ECG electrodes 18, electrode patches 38, an ablation energy generator 50, and a recorder 11. Optionally and preferably, the PIU 30 additionally includes processing power for enabling real-time calculation of the position of the catheter and for performing ECG calculations.

The workstation 55 includes memory, a processor unit with memory or storage loaded with appropriate operating software, and user interface capabilities. Workstation 55 may provide a number of functions, including optionally: (1) Three-dimensional (3D) modeling of endocardial anatomy and rendering of the model or anatomical map 20 for display on display device 27; (2) Displaying the activation sequence (or other data) compiled from the recorded electrogram 21 on a display device 27 with a representative visual marker or image superimposed on the rendered anatomic map 20; (3) Displaying real-time positions and orientations of a plurality of catheters within a heart chamber; and (4) displaying the site of interest (such as where ablation energy has been applied) on a display device 27. A commercial product embodying elements of system 10 is available from the Biosense Webster, inc.,31TechnologyDrive,Suite 200,Irvine,CA 92618,USA as a CARTO ^TM system.

Fig. 2A is a schematic illustration showing a perspective view of the medical probe 16 including a generally cylindrical structure 60 in an expanded form when unconstrained, such as by being pushed out of an insertion tube lumen 82 at a distal end 83 of an insertion tube 80. The medical probe 16 shown in fig. 2A lacks the introducer sheath shown in fig. 1. Fig. 2B shows the generally cylindrical structure 60 in a collapsed form within the insertion tube 80 of the introducer sheath. During a medical procedure, physician 24 may deploy cylindrical structure 60 by extending tubular shaft 84 from insertion tube 80, causing cylindrical structure 60 to exit insertion tube 80 and transition to an expanded form. Each spine member 220 of the plurality of spine members 22 is aligned at a distal end 225 and a proximal end 222 of the generally cylindrical structure 60 and along the longitudinal axis 86. Each spine member 220 may have an oval (e.g., circular) or rectangular (which may appear flat) cross-section and comprise a flexible, resilient material (e.g., a shape memory alloy such as nitinol, also referred to as nitinol) that forms the spine member, as will be described in more detail herein. The ridge member 220 may have a nominal width of about 0.6mm and may be as low as 0.05mm or as high as 1.5mm. The thickness of each ridge member may be about 0.09mm and may vary between 0.01mm and 2 mm. It should be noted that these values of width and thickness may vary depending on the stiffness desired.

As shown in fig. 2A, the generally cylindrical structure 60 includes a proximal circular base 62 (not visible through the membrane 70 in fig. 2A) and a distal circular base 65 such that the proximal base 62 and the distal base 65 are generally flat and parallel. In some examples, the distal circular base 65 includes a smaller radius than the proximal circular base 62 such that the generally cylindrical structure 60 tapers with a proximal portion being larger than a distal portion. Alternatively, some example medical probes 16 have a generally cylindrical structure 60 with a radius at a distal circular base 65 that is greater than a radius at a proximal circular base 62 such that the generally cylindrical structure 60 tapers with a distal portion that is greater than a proximal portion. As shown, the radius of the distal circular base 65 is similar to the proximal circular base 62.

Fig. 3 is an exploded side view of medical probe 16, showing ridge member 220, when the plurality of ridge members 22 are aligned, forming a generally cylindrical structure 60. In addition, the medical probe 16 includes a membrane 70 having an electrode array including an outer electrode 26a on an outer surface of the membrane 70, an inner or reference electrode 26b on an inner surface of the membrane 70, and a mapping electrode 26c on a planar surface of the membrane 70. The membrane 70 also has apertures 72 along the body of the membrane that allow fluid to enter the interior volume 66 such that there is fluid communication between the exterior of the membrane 70 and the interior volume 66. As shown in fig. 2A, the membrane 70 fits over the plurality of ridges 22 that expand into a generally cylindrical shape. In some embodiments, the membrane aperture 72 may extend along the entire length of the membrane 70, as shown in fig. 3, or may be limited near the distal and/or proximal ends of the membrane 70.

The generally cylindrical structure 60 may be physically connected to the tubular member 84 via a suitable technique, such as adhesive or molding. In one embodiment, not shown, an eyelet may be provided along the proximal ring 232 and a locator provided on the surface of the tubular member 84 to aid in assembly and to physically retain the ridge to the tubular member 84. The plurality of spine members 22 may be folded or otherwise bent such that each spine member 220 or proximal ring 232 may be inserted into the distal end 85 of the tubular shaft 84 (as shown in fig. 3). The electrode 26 may be formed directly onto the spine member 220 using, for example, vacuum deposition. Vacuum deposition may include, but is not limited to, physical vapor deposition or chemical vapor deposition. It should be appreciated that by forming the electrodes directly onto the spine member 220 using vacuum deposition, the disclosed techniques may reduce or eliminate many of the complications and errors associated with forming and spine-separated electrodes and subsequently assembling the electrodes onto the spine. Although not shown in fig. 3, it should be appreciated that the electrodes 26 may be attached to the membrane 70 using vacuum deposition (e.g., physical vapor deposition) prior to positioning the membrane 70 over the plurality of spine members 22 and inserting the spine members 22 into the tubular shaft 84 to form the medical probe 16. As previously described, the spine members 22 may comprise a flexible, resilient material (e.g., a shape memory alloy such as nickel titanium (also referred to as nitinol)) such that each spine member 20 may be bent into a configuration and enable the generally cylindrical structure 60 to transition to its expanded form when the generally cylindrical structure 60 is deployed from the tubular shaft 84.

As shown in fig. 3, the plurality of spine members 22 extend along the longitudinal axis 86 between a distal end 225 and a proximal end 222 of the cylindrical structure. The plurality of spine members 22 are aligned along each straight portion 211c of the spine members 22 such that the distal end 225 of the cylindrical structure 16 includes a distal bend 215 of each spine member 220 and the proximal portion 216 of each spine member 220 is coupled with a proximal ring 232 at the proximal end 212 of the generally cylindrical structure 60.

Turning to fig. 4A-4C, the spine member 220 may be fabricated from a continuous piece of flat stock material 210. The spine member 220 may be stamped from such material and heat treated to bend into a configuration, examples of which are shown in fig. 4B and 4C. The flat stock 210 is cut into the desired shape of the spine member. Thereafter, as known to those skilled in the art, the cut material 210 may be shaped (or heat set) to provide a plurality of spine members 22 aligned together to form the generally cylindrical configuration shown in fig. 2A, 3 and 6.

As shown more clearly in fig. 4B and 4C, each of the plurality of spine members 22 includes a first section 211a extending along the longitudinal axis 86 from the first end 212 to the first bend 213, a second section 211B extending from the first section 211a curvingly relative to the longitudinal axis, and a third section 211C extending along the longitudinal axis from the second bend 215 to the second end 218 such that a proximal portion 216 of the third section 211C is substantially parallel to the first section 211a. Along a portion of second section 211b, spine member 220 includes bifurcation point 217 such that a portion of second section 211b has a continuous leg 217c extending between bifurcation point 217 and first end 212 and a discontinuous leg 217d extending along the length of second section 211b between bifurcation point 217 and some termination point 219. Although not shown, the discontinuous leg 217d may extend from the bifurcation point 217 along the length of the second section 211b and optionally along the length of the first section 211a such that the discontinuous leg 217d terminates at a point substantially equal to the first end 212. The second section 211b also includes a distal portion 214 extending between the bifurcation 217 and the second bend 215. In some examples, as shown in fig. 4B, the bifurcation 217 is positioned near the second bend such that the distal portion 214 is shorter, while the bifurcation 217 of fig. 4C is positioned closer to the first bend 213 and the distal portion 214 is longer.

Fig. 5A and 5B are schematic illustrations showing side views (fig. 5A) and top views (fig. 5B) of two adjacent spine members 220a, 220B aligned along straight portion 211c and having different bifurcation points 217a, 217B. In some embodiments, as shown herein, the distal portion 214b does not affect the termination point 219 of the discontinuous leg 217d of the adjacent spine member 220a, 220 b. When the distal portion 214 forms a generally planar portion of the generally cylindrical structure 60, at least two distal circular bases 65a, 65b may be formed. As shown in fig. 5B, having different bifurcation points 217a, 217B changes the length of the distal portions 214a, 214B. In some examples, as shown in fig. 5A, the length of distal portion 214a is changed,

Fig. 6 is a schematic illustration showing a perspective view of a generally cylindrical structure 60 in an expanded form having a plurality of fractal ridge members 22 with different bifurcation points 217a, 217b forming a first distal circular base 65a and a second distal circular base 65 b. When in the expanded form, the intermediate portion 221 of each of the spine members 22 between the first and second distal circular bases 65a, 65b and the proximal circular base 62 forms the outermost portion of the cylindrical structure 60. In some exemplary medical probes 16, the intermediate portion 221 has a length ranging from about 10mm to about 20 mm. Preferably, the length L of the cylindrical structure 60 between the proximal end 222 and the distal end 225 is about 15mm.

Fig. 7A is a schematic illustration showing a perspective view of a generally cylindrical structure 60 formed from a plurality of fractal ridge members 22, with an exemplary fractal ridge member 22 design shown in fig. 7B. As shown, each spine member 220 includes a first end 212 and a second end 218. Unlike the spine member 220 designs of fig. 4B and 4C, the generally cylindrical structure 60 lacks any portion of the spine member 220 within the interior volume 66 of the structure. A plurality of spine members 22 are coupled at each respective second end 218 of spine members 220 rather than at the second bends. Each spine member 220 includes at least one bifurcation point 217 and a convergence point 227 along the longitudinal axis 86 of the generally cylindrical structure 60. The spine member 220 of fig. 7B provides two bifurcation points 217, 217' and two convergence points 227, 227', with one bifurcation point 217 being closer to the proximal side than the second bifurcation point 217 '. It will be appreciated that having two or more bifurcation points extending along the length of the fractal ridge member provides additional surface area for placement of the electrodes and enhanced structure for the generally cylindrical structure, and may reduce or eliminate the complexity of structural support of the medical probe during surgery.

In some embodiments, electrical traces 96 are embedded within the membrane and connect one or more electrodes 26a that are coupled to the outer surface of the membrane 70, as shown in fig. 2A and 8C. In fig. 3, the membrane 70 includes electrodes on the outer surface 26a, electrodes on the inner surface 26b, and mapping electrodes 26c on the distal planar surface of the cylindrical structure 60. The mapping electrode 26c may be a conventional coil sensor, a flat PCB-based sensor, or a deformable electromagnetic ring sensor. Although not shown, the mapping electrode 26c may alternatively be positioned on the generally cylindrical structure 60 or designed as a separate ridge section 210 of the plurality of ridges 22. In some embodiments, individual ridge segments 210 of the plurality of ridges 22 may be insulated and act as position sensors.

Electrodes are disposed on the outer surface of the membrane 70 and on the inner surface of the membrane 70 such that the electrodes define a pair of stacked electrodes 26. The electrode 26 disposed on the inner surface of the membrane may be used as a reference electrode. The reference electrode may measure electrical signals from the fluid in the interior volume 66 of the medical probe 16 to reduce noise, improve mapping accuracy, and the like. The reference electrode may be configured to measure electrical signals from fluid and/or blood directly adjacent to the electrode contacting the tissue. Thus, the reference electrode does not contact tissue, and the resulting signal collected is a non-local far-field signal. Information from the reference electrode may be used to cancel far field signals from adjacent tissue contacting electrodes to ensure that only local information is collected by the tissue contacting electrodes.

In embodiments described herein, one or more electrodes 26 positioned on the membrane 70 of the cylindrical structure 60 may be configured to deliver ablation energy (RF and/or IRE) to tissue in the heart 26. The plurality of ridge members 22 may be electrically insulated from the electrode 26 to prevent arcing of the electrode 26 to the corresponding ridge member 220. In addition, the electrodes may also be used to determine the position of medical probe 16 and/or to measure physiological characteristics, such as local surface potentials at corresponding locations on tissue in heart 26. The electrodes 26 may be biased such that a greater portion of one or more electrodes 26a face outwardly from the generally cylindrical structure 60 such that the one or more electrodes 26a deliver a greater amount of electrical energy outwardly away from the cylindrical structure 60 (i.e., toward the heart 12 tissue) than inwardly.

Examples of materials that are ideally suited for forming electrode 26 include gold, platinum, and palladium (and their corresponding alloys). These materials also have a high thermal conductivity, which allows the minimal heat generated on the tissue (i.e., by the ablation energy delivered to the tissue) to be conducted through the electrode to the back of the electrode (i.e., the portion of the electrode on the inside of the ridge) and then to the blood pool in the heart 12.

As described above, the PIU 30 and workstation 55 include a controller for irrigation that delivers irrigation fluid to the medical probe 16. Although not shown, a plurality of irrigation openings may be positioned within the interior volume 66 of the generally cylindrical structure 60 and angled to spray or otherwise disperse irrigation fluid to tissue in a given electrode 26 or heart 12. Since the electrode 26 does not include irrigation openings that deliver irrigation fluid, the described configuration enables heat transfer from the tissue to the portions of the electrode on the inner sides of the plurality of ridges 22 (i.e., during an ablation procedure), and the electrode 26 may be cooled by aligning the irrigation fluid with the portions of the electrode 26 on the inner sides of the ridges 22 via the irrigation openings.

Fig. 8A and 8B are schematic illustrations showing perspective views of various example membranes 70A, 70B having arrays of electrodes 26a, 26B, 26c, an aperture 72 along the surface of the membranes 70A, 70B, a proximal attachment point 72, and a distal attachment point 75. Fig. 8A illustrates an outer surface of an example membrane 70A, which may include electrodes 26a on the outer surface and mapping electrodes 26c configured to be positioned on a substantially planar surface of a substantially cylindrical structure 60. Fig. 8B shows an inner surface of an example membrane 70B having an electrode 26B configured to face the interior volume 66 of the generally cylindrical structure 60. The film 70A of fig. 8A shows a plurality of proximal attachment points 72a and distal attachment points 75a, while the film 70B of fig. 8B has a uniform proximal attachment point 72B and a uniform distal attachment point 75B. Although not shown, the membrane 70 may be designed from a planar material with the proximal attachment point 72 centered and the material extending proximally along the longitudinal axis 86.

In some embodiments described herein, the membranes 70A, 70B include an array of electrodes 26a, 26B distributed along the outer and/or inner surfaces of the membranes 70A, 70B, respectively. As shown in fig. 8A, the electrodes 26c extend along the proximal attachment point to form a generally planar electrode array at the distal tip 28 of the medical probe 16, which may be used to map cardiac tissue 12, as described above with reference to fig. 3. Fig. 8C is a schematic illustration showing a close-up of the electrode 26 and electrical trace 96 on the film 70 of fig. 8B.

The films 70A, 70B may be made of biocompatible electrically insulating materials such as polyamide-polyether (Pebax) copolymers, polyethylene terephthalate (PET), polyurethane, polyimide, parylene, silicone, and combinations thereof. In some examples, the insulating material may include biocompatible polymers including, but not limited to, polyethylbenzene, polydimethylsiloxane, polyglycolic acid, poly-L-lactic acid, polycaprolactone (polycaprolactive), polyhydroxybutyrate, polyhydroxyvalerate, polydioxanone, polyamide, polyimide, ethylene vinyl acetate, polyvinylidene fluoride, polycarbonate, polypropylene, polyethylene, polyurethane, polyethylene terephthalate, polyethylene naphthalate, polyanhydride, polycaprolactone, polydioxanone, polybutylene lactone, polyglutarite, poly (lactide-co-glycolide), polydimethylsiloxanes, silicones, epoxy resins, fluoropolymers, polytetrafluoroethylene, the proportions of some polymers being selected to control the extent of the inflammatory reaction. The insulating jackets 880A, 880B may also include one or more additives or fillers, such as Polytetrafluoroethylene (PTFE), boron nitride, silicon carbide, aluminum oxide, aluminum nitride, zinc oxide, and the like. The films 70A, 70B may help insulate the plurality of ridges 22, electrical traces 96, or wires passing through the films 70A, 70B from the electrode 26 to prevent arcing of the plurality of ridge members 22 by the electrode 26 and/or mechanical wear of the wires passing through the films 70A, 70B.

Fig. 9 is a flow chart illustrating a method 900 of manufacturing a medical probe 16 according to an embodiment of the present invention. The method 900 may include stamping a plurality of spine members 22 from a continuous sheet of flat stock material 210 (step 902). Method 900 may also include heat treating the plurality of spine members 22 such that each spine member 210 forms a configuration that when aligned forms a generally cylindrical structure 60. Each spine member 210 may include a first section 211a extending along the longitudinal axis 86 from a first end 212 to a first bend 213; a second section 211b extending curvilinearly from the first section 211a relative to the longitudinal axis 86; and a third section 211c extending along the longitudinal axis 86 from the second bend 215 to the second end 218 such that a proximal portion 216 of the third section 211c is substantially parallel to the first section 211a (step 904). The method 900 may optionally include the steps of: the spine member 220 is split along a portion of the second section 211b at the bifurcation point 217 to form a continuous leg 217c extending between the first section 211a and the bifurcation point 217, and a discontinuous leg 217d extending from the bifurcation point 217 toward the second section 211b and terminating at a termination point 219 between the bifurcation point 217 and the first end 212. The method 900 includes aligning the distal curved portions 215 of at least four spine members 210 to define a generally cylindrical structure 60 (step 906).

In some examples, steps 902 through 906 may occur as simultaneous steps or as a series of steps.

Fig. 10 is a flow chart illustrating a method 1000 of manufacturing a medical probe 16 according to an embodiment of the present invention. Method 1000 may include fabricating one or more electrical traces 96 on film 70 (step 1002). Fabrication of the electrical traces 96 may be completed prior to or simultaneously with alignment of the one or more electrodes 26 within the one or more electrical traces 96 on the film 70 (step 1004). The membrane 70 may include an electrode array including an outer electrode 26a, an inner or reference electrode 26b, and a mapping electrode 26c on a planar surface. The electrodes may be positioned such that the electrodes 26 are offset from adjacent electrodes 26 along the membrane 70 or within a linear array. Materials that are ideally suited for forming electrode 26 include gold, platinum, and palladium (and their corresponding alloys). The method 1000 may optionally include adding one or more orifices 72 along a surface of the membrane 70 such that fluid may flow within the interior volume 66 of the membrane 70 (step 1006). The membrane may be cut from a planar elastic material. The planar elastic material may include a shape memory alloy such as nickel-titanium (also known as nitinol) or a biocompatible polymer including, but not limited to, polyethylbenzene, polydimethylsiloxane, polyglycolic acid, poly-L-lactic acid, polycaprolactone, polyhydroxybutyrate, polyhydroxyvalerate, polydioxanone, polyamide, polyimide, ethylene vinyl acetate, polyvinylidene fluoride, polycarbonate, polypropylene, polyethylene, polyurethane, polyethylene terephthalate, polyethylene naphthalate, polyanhydride, polycaprolactone, polydioxanone, polybutylene lactone, polycaprolactone, poly (lactide-co-glycolide), polydimethylsiloxane, silicone, epoxy, fluoropolymer, polytetrafluoroethylene, or combinations thereof. In some examples, the method 1000 may form a film by vapor deposition (e.g., chemical Vapor Deposition (CVD), physical Vapor Deposition (PVD), or Atomic Layer Deposition (ALD)). For vapor deposition, a nitinol layer may be deposited, followed by a thin insulating layer, then a conductive trace layer and an electrode layer. In some examples, method 1000 may form a film by a photolithographic method, a sputtering method (e.g., spin coating, direct write sputtering, or sputter coating), printing (e.g., 3D printing), electrodeposition, photolithography.

The method 1000 further includes positioning the film 70 over the plurality of discrete ridge members 220 shaped to form the generally cylindrical structure 60, as described in more detail with reference to the method 900 (step 1008). The membrane 70 may be secured over the plurality of spine members 22 as described herein. As will be appreciated by those skilled in the art having the benefit of this disclosure, the fastening film 70 may include a proximal ring 232 that attaches the proximal attachment point 72 to the plurality of spine members 22 or to the tubular shaft 84. Method 1000 may include configuring the plurality of spine members 22 to extend radially outward from the longitudinal axis 86 to define the generally cylindrical structure 60 (step 1010). As described above, the plurality of spine members 22 includes at least a bifurcation 217 along at least a portion of the spine member 220.

In some examples, steps 1002 through 1010 may occur as simultaneous steps or as a series of steps. In some examples, method 900 and steps 902 through 906 may occur immediately prior to method 1000 and steps 1002 through 1010.

The method 1000 may further include inserting each spine member 220 or proximal ring 232 into a lumen of a tubular shaft 84 sized to traverse the vasculature such that the generally cylindrical structure 60 is positioned at the distal end of the medical probe 16 and the respective spine member 220 is movable from the tubular configuration to the arcuate configuration.

As will be appreciated by those of skill in the art, the method 1000 may include any of the various features of the disclosed technology described herein and may vary depending on the particular configuration. Thus, the method 1000 should not be construed as limited to the particular steps and sequence of steps explicitly described herein. It is noted that while the exemplary embodiment of the medical probe is preferably used for mapping, IRE or PFA, it is also within the scope of the invention to use the medical probe alone for RF ablation only (monopolar mode or bipolar mode with external ground electrode), or in combination with IRE ablation and RF ablation sequentially (some electrodes in IRE mode and other electrodes in RF mode) or simultaneously (electrode set in IRE mode and other electrodes in RF mode).

The disclosed technology described herein may be further understood in light of the following clauses:

Clause 1: a spine member for use in a medical probe, the spine member comprising: a first section extending along a longitudinal axis from a first end to a first bend; a second section extending curvilinearly from the first section relative to the longitudinal axis and including a bifurcation point; and a third section extending along the longitudinal axis from a second bend to a second end such that a proximal portion of the third section is substantially parallel to the first section.

Clause 2: the spine member of clause 1, wherein the spine member is stamped from a continuous sheet of flat stock material and heat treated to its configuration.

Clause 3: the spine member of clause 1, the second section comprising: a continuous leg extending between the first section and the bifurcation point; and a discontinuous leg extending toward the first section and terminating at a termination point between the bifurcation point and the first end.

Clause 4: the spine member of clause 1, the second section comprising: a distal portion extending between the bifurcation point and the second bend.

Clause 5: the spine member of clause 1 configured to align with four or more spine members in their respective configurations to form a generally cylindrical structure.

Clause 6: the spine member of clause 5, wherein the third sections of the four or more spine members are aligned such that the second curved portion of each spine member forms a distal tip of the generally cylindrical structure.

Clause 7: a medical probe comprising a plurality of spine members disposed about a longitudinal axis to define a generally cylindrical structure, each of the plurality of spine members comprising: a first section extending along the longitudinal axis from a first end to a first bend; a second section extending curvilinearly from the first section relative to the longitudinal axis and including a bifurcation point; and a third section extending along the longitudinal axis from a second bend to a second end such that a proximal portion of the third section is substantially parallel to the first section; and a plurality of electrodes coupled to each of the plurality of spine members.

Clause 8: the medical probe of clause 7, further comprising a membrane surrounding the plurality of ridge members to define an interior volume, the membrane comprising: a plurality of apertures to allow fluid communication from the interior volume to the ambient environment; a plurality of external electrodes disposed on an outer surface of the membrane; and a plurality of internal electrodes disposed on an inner surface of the film.

Clause 9: the medical probe of clause 7 or 8, the generally cylindrical structure being configured to move from a deployed tubular configuration to an expanded configuration.

Clause 10: the medical probe of any one of clauses 7-9, the generally cylindrical structure comprising a generally flat distal portion circular base.

Clause 11: the medical probe of any of clauses 7-10, the generally cylindrical structure comprising a generally flat proximal portion circular base.

Clause 12: the medical probe of any one of clauses 9-11, the second section of each ridge member forming a middle portion defining an outermost portion of the generally cylindrical structure in the expanded configuration, the generally cylindrical structure including a middle portion having a length in a range from about 10mm to about 20 mm.

Clause 13: the medical probe of any of clauses 7-11, wherein the generally cylindrical structure comprises at least four discrete ridge members.

Clause 14: the medical probe of clause 13, wherein the generally cylindrical structure comprises eight discrete ridge members.

Clause 15: the medical probe of any of clauses 11-14, wherein the distal circular base has a smaller radius than the proximal circular base.

Clause 16: the medical probe of any of clauses 11-14, wherein the distal circular base has a larger radius than the proximal circular base.

Clause 17: the medical probe of any of clauses 11-14, wherein the distal circular base has a radius approximately equal to the proximal circular base.

Clause 18: the medical probe of any of clauses 11-14, wherein the distal circular base is oriented substantially parallel to the proximal circular base.

Clause 19: the medical probe of any one of clauses 7-18, the first end of each respective discrete ridge member converging into a proximal ring at the proximal end of the cylindrical structure.

Clause 20: the medical probe of any one of clauses 1-16, the cylindrical structure further comprising one or more electromagnetic positioning coils on one or more of the plurality of discrete ridge members.

Clause 21: a medical probe, comprising:

A generally cylindrical structure comprising a plurality of discrete ridge members, the ridge members comprising: a distal bend; an intermediate portion; and a first ridge end; the plurality of spine members are disposed together at a distal end of the generally cylindrical structure at each respective distal bend and at a proximal end of the generally cylindrical structure at each respective first spine end, and each respective intermediate portion is bent axially from the longitudinal axis to form an outer surface of the generally cylindrical structure.

Clause 22: the medical probe of clause 21, the discrete ridge member further comprising a straight portion between the distal bend and the second ridge end of the respective ridge segment, the straight portion being positioned in the generally cylindrical structure.

Clause 23: the medical probe of clause 22, wherein the first ridge end of each ridge segment meets the second ridge end of the ridge segment when the generally cylindrical structure is in the expanded configuration.

Clause 24: the medical probe of clause 22 or 23, the generally cylindrical structure formed by the plurality of discrete ridge members aligning each straight portion of a respective ridge segment adjacent to a straight portion of an adjacent ridge segment.

Clause 25: the medical probe of clause 21, the discrete ridge member further comprising a bifurcated portion between the first ridge end and the second ridge end.

Clause 26: the medical probe of any of clauses 21-25, the generally cylindrical structure being configured to move from a deployed tubular configuration to an expanded configuration.

Clause 27: the medical probe of any one of clauses 21-26, the generally cylindrical structure comprising a generally flat distal portion circular base.

Clause 28: the medical probe of any one of clauses 21-27, the generally cylindrical structure comprising a generally flat proximal portion circular base.

Clause 29: the medical probe of any of clauses 21-28, the generally cylindrical structure comprising a middle portion having a length in the range of from about 10mm to about 20 mm.

Clause 30: the medical probe of any of clauses 21-29, wherein the generally cylindrical structure comprises at least four discrete ridge members.

Clause 31: the medical probe of clause 30, wherein the generally cylindrical structure comprises eight discrete ridge members.

Clause 32: the medical probe of any of clauses 28-31, wherein the distal circular base has a smaller radius than the proximal circular base.

Clause 33: the medical probe of any of clauses 28-31, wherein the distal circular base has a larger radius than the proximal circular base.

Clause 34: the medical probe of any of clauses 28-31, wherein the distal circular base has a radius approximately equal to the proximal circular base.

Clause 35: the medical probe of any of clauses 28-34, wherein the distal circular base is oriented substantially parallel to the proximal circular base.

Clause 36: the medical probe of any one of clauses 21-35, the first end of each respective discrete ridge member converging into a proximal ring at the proximal end of the generally cylindrical structure.

Clause 37: the medical probe of any of clauses 21-36, the generally cylindrical structure further comprising one or more electromagnetic positioning coils on one or more of the plurality of discrete ridge members.

Clause 38: the medical probe of clause 37, the generally cylindrical structure further comprising a membrane positioned over the plurality of ridge members, the membrane comprising one or more electrodes coupled to an outer surface of the membrane.

Clause 39: the medical probe of clause 38, the membrane comprising one or more apertures to allow fluid communication from the interior volume to the surrounding environment.

Clause 40: the medical probe of clause 39, the membrane further comprising one or more conductive traces disposed on a surface of the membrane between the one or more apertures, each electrical trace being connected to a respective electrode of the plurality of electrodes.

Clause 41: the medical probe of any one of clauses 38-40, the film being formed of a planar material.

Clause 42: the medical probe of any of clauses 38-41, wherein the one or more electrodes are positioned on the membrane such that the one or more electrodes are aligned with at least a portion of the intermediate portion of the generally cylindrical structure.

Clause 43: the medical probe of any one of clauses 38-42, the membrane further comprising one or more reference electrodes coupled to an inner surface of the membrane.

Clause 44: the medical probe of any of clauses 38-43, wherein the one or more electrodes are configured to deliver an electrical pulse for irreversible electroporation, the pulse having a peak voltage of at least 900 volts.

Clause 45: the medical probe of any one of clauses 21-44, further comprising an irrigation opening disposed proximate the distal end of the tubular shaft, the irrigation opening configured to deliver irrigation fluid to the one or more electrodes.

Clause 46: the medical probe of any of clauses 21-45, wherein the plurality of ridge members comprise nitinol.

Clause 47: the medical probe of any of clauses 21-45, wherein the plurality of ridge members comprise metal strands.

Clause 48: the medical probe of any of clauses 38-47, wherein the membrane comprises nitinol.

Clause 49: the medical probe of any of clauses 38-47, wherein the membrane comprises an inert biocompatible polymer.

Clause 50: the medical probe of clause 49, the inert biocompatible polymer being selected from the group consisting of: polyethylbenzene, polydimethylsiloxanes, polyglycolic acid, poly-L-lactic acid, polycaprolactone, polyhydroxybutyrate, polyhydroxyvalerate, polydioxanone, polyamide, polyimide, ethylene vinyl acetate, polyvinylidene fluoride, polycarbonate, polypropylene, polyethylene, polyurethane, polyethylene terephthalate, polyethylene naphthalate, polyanhydride, polycaprolactone, polydioxanone, polybutylene lactone, polycaprolactone, poly (lactide-co-glycolide), polydimethylsiloxanes, silicones, epoxy resins, fluoropolymers, polytetrafluoroethylene, or combinations thereof.

Clause 51: a method of constructing a medical probe, the method comprising:

Stamping a plurality of ridge members from a continuous sheet of flat stock material; heat treating the plurality of spine members such that each spine member forms a configuration comprising: a first section extending along a longitudinal axis from a first end to a first bend; a second section extending curvilinearly from the first section relative to the longitudinal axis; and a third section extending along the longitudinal axis from a second bend to a second end such that a proximal portion of the third section is substantially parallel to the first section; and aligning the distal bends of the at least four spine members to define a generally cylindrical structure.

Clause 52: the method of clause 51, further comprising:

The spine member is split along a portion of the second section at a bifurcation point to form a continuous leg extending between the first section and the bifurcation point and a discontinuous leg extending toward the second section and terminating at a termination point between the bifurcation point and the first end.

Clause 53: the method of clause 52, wherein the spine member is split at a plurality of points along the distal portion of the second section such that the first spine member includes a first bifurcation point at a first location and the second spine member includes a second bifurcation point at a second location.

Clause 54: the method of clause 53, further comprising adjacently aligning the first ridge member with the second ridge member.

Clause 55: the method of any one of clauses 51-54, further comprising coupling a plurality of electrodes to each of the plurality of spine members.

Clause 56: the method of any one of clauses 51-55, further comprising positioning a film over the substantially cylindrical structure, the film comprising one or more electrical traces on a surface of the film.

Clause 57: a method of constructing a medical probe, the method comprising: fabricating one or more electrical traces on the film; aligning one or more electrodes within the one or more electrical traces; and positioning the film over a plurality of discrete ridge members shaped to form a generally cylindrical structure.

Clause 58: the method of clause 57, further comprising: the discrete ridge members are stamped from a continuous sheet of flat stock material.

Clause 59: the method of clause 58, further comprising: cutting a distal straight portion having a first width and a proximal straight portion having a second width; and cutting at least a portion of the proximal straight portion into a continuous leg and a discontinuous leg, the discontinuous leg forming a bifurcated portion of the respective spine member.

Clause 60: the method of any one of clauses 57-59, further comprising:

one or more apertures are added to the surface of the membrane.

Clause 61: the method of any one of clauses 57-60, further comprising securing the film over the substantially cylindrical structure.

Clause 62: the method of any one of clauses 57-61, further comprising connecting one or more electrical traces to a wire traveling through a tubular shaft of the medical probe.

Clause 63: the method of any one of clauses 57 to 61, further comprising printing the film by physical vapor deposition.

Clause 64: the method of any one of clauses 57-63, further comprising cutting the film from a planar sheet comprising nitinol.

Clause 65: the method of any of clauses 57-64, further comprising positioning one or more electromagnetic positioning coils on the plurality of spine members of the generally cylindrical structure.

Clause 66: the method of any of clauses 57-65, the plurality of ridge members further comprising a straight portion, the method comprising:

the straight portion of each respective ridge member is arranged in the centre of the substantially cylindrical structure.

Clause 67: the method of clause 66, further comprising positioning the film over the plurality of ridge members such that the one or more electrodes are aligned with at least a portion of the middle portion of the cylindrical structure.

The above embodiments are cited by way of example, and the present invention is not limited to what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes both combinations and sub-combinations of the various features described and illustrated above, as well as variations and modifications thereof which would occur to persons skilled in the art upon reading the foregoing description and which are not disclosed in the prior art.

Claims

1. A spine member for use in a medical probe, the spine member comprising:

A first section extending along a longitudinal axis from a first end to a first bend;

A second section extending curvilinearly from the first section relative to the longitudinal axis and including a bifurcation point; and

A third section extending along the longitudinal axis from a second bend to a second end such that a proximal portion of the third section is substantially parallel to the first section.

2. The spine member of claim 1, the second section comprising:

A continuous leg extending between the first section and the bifurcation point; and

A discontinuous leg extending toward the first section and terminating at a termination point between the bifurcation point and the first end.

3. The spine member of claim 1, the second section comprising:

a distal portion extending between the bifurcation point and the second bend.

4. The spine member of claim 1 configured to align with four or more spine members in their respective configurations to form a generally cylindrical structure.

5. The spine member of claim 4 wherein the third sections of the four or more spine members are aligned such that the second curvature of each spine member forms a distal tip of the generally cylindrical structure.

6. A medical probe, comprising:

A generally cylindrical structure comprising a plurality of discrete ridge members, the plurality of discrete ridge members comprising:

A distal bend;

An intermediate portion; and

A first ridge end;

The plurality of discrete spine members are disposed together at a distal end of the generally cylindrical structure at each respective distal bend and are disposed together at a proximal end of the generally cylindrical structure at each respective first spine end, an

Each respective intermediate portion is bent axially from the longitudinal axis to form an outer surface of the generally cylindrical structure.

7. The medical probe of claim 6, the discrete spine members further comprising a straight portion between the distal bend and second spine end of the respective discrete spine member, the straight portion being positioned in the generally cylindrical structure.

8. The medical probe of claim 7, wherein the first ridge end of each ridge member meets the second ridge end of the ridge member when the generally cylindrical structure is in an expanded configuration.

9. The medical probe of claim 7, the generally cylindrical structure formed by the plurality of discrete spine members aligning each straight portion of a respective spine member adjacent to the straight portion of an adjacent spine member.

10. The medical probe of claim 7, the discrete ridge member further comprising a bifurcated portion between the first ridge end and the second ridge end.

11. The medical probe of claim 6, the first spine end of each respective discrete spine member converging into a proximal loop at the proximal end of the generally cylindrical structure.

12. The medical probe of claim 6, the generally cylindrical structure further comprising one or more electromagnetic positioning coils on one or more of the plurality of discrete spine members.

13. The medical probe of claim 12, the generally cylindrical structure further comprising a membrane positioned over the plurality of discrete ridge members, the membrane comprising one or more electrodes coupled to an outer surface of the membrane.

14. The medical probe of claim 13, the membrane comprising one or more apertures to allow fluid communication from the interior volume to the surrounding environment.

15. The medical probe of claim 14, the membrane further comprising one or more conductive traces disposed on a surface of the membrane between the one or more apertures, each electrical trace connected to a respective electrode of the one or more electrodes.

16. The medical probe of claim 13, the membrane further comprising one or more reference electrodes coupled to an inner surface of the membrane.

17. A method of constructing a medical probe, the method comprising:

stamping a plurality of ridge members from a continuous sheet of flat stock material;

Heat treating the plurality of spine members such that each spine member forms a configuration comprising:

a second section extending curvilinearly from the first section relative to the longitudinal axis; and

A third section extending along the longitudinal axis from a second bend to a second end such that a proximal portion of the third section is substantially parallel to the first section; and

The first curved portions of the plurality of ridge members are aligned to define a generally cylindrical structure.

18. The method of claim 17, the method further comprising:

19. The method of claim 18, wherein the spine member is split at a plurality of points along a distal portion of the second section such that a first spine member includes a first bifurcation point at a first location and a second spine member includes a second bifurcation point at a second location.

20. The method of claim 17, further comprising positioning a film over the substantially cylindrical structure, the film comprising one or more electrical traces on a surface of the film.