Basket catheter with solid conductive ridges as electrodes for IRE

Abstract

The invention is entitled "Basket Catheter with Solid Conductive Ridges as Electrodes for IRE". The invention discloses a medical device comprising a probe comprising: an insertion tube configured for insertion into a body cavity of a patient; and a basket assembly connected distally to the insertion tube and comprising a plurality of resilient conductive ridges configured to contact tissue in the body. The device further comprises an electrical signal generator configured to apply between one or more pairs of ridges a bipolar pulse having an amplitude sufficient to induce irreversible electroporation (IRE) in the tissue contacted by the ridges.

Description

Technical Field

[0001] This invention relates generally to medical devices, and more specifically to devices and methods for ablating tissues in vivo. Background Technology

[0002] Irreversible electroporation (IRE) is a soft tissue ablation technique that applies short pulses of a strong electric field to create permanent and therefore lethal nanopores in the cell membrane, thereby disrupting cellular homeostasis (internal physical and chemical conditions). Cell death following IRE is due to apoptosis (programmed cell death) rather than necrosis (cell damage, which leads to cell destruction through the action of its own enzymes), as is the case in other heat- and radiation-based ablation techniques. IRE is commonly used for tumor ablation in areas where the precision and preservation of the extracellular matrix, blood flow, and nerves are crucial. Summary of the Invention

[0003] The embodiments of the present invention described below provide improved systems and methods for ablation of tissues in vivo.

[0004] Therefore, according to an embodiment of the present invention, a medical device including a probe is provided. The probe includes: an insertion tube configured for insertion into a patient's body cavity; a basket-shaped assembly distally connected to the insertion tube; and a plurality of resilient conductive ridges configured to contact tissue within the body. The device also includes an electrical signal generator configured to apply bipolar pulses between one or more pairs of ridges, the bipolar pulses having an amplitude sufficient to induce irreversible electroporation (IRE) in the tissue contacted by the ridges.

[0005] In the embodiments disclosed in this invention, the spine has a corresponding proximal end and a distal end, wherein the proximal end of the spine is mechanically engaged at the proximal end of the basket assembly, and the distal end of the spine is mechanically engaged at the distal end of the basket assembly, and when the basket assembly is deployed in a body cavity, the spine bends radially outward to contact the tissue in the body cavity.

[0006] In another embodiment of the invention, the basket assembly has a stable collapsed state, and the device includes a puller attached to the distal end of the basket assembly and slidably disposed within the insertion tube, such that the ridge bends radially outward in response to pulling the puller proximally through the insertion tube. Alternatively, the puller may include a reinforced polymer tube.

[0007] In some implementations, the insertion cannula includes a flexible catheter configured to be inserted into a chamber of a patient's heart, and a ridge is configured to contact the myocardial tissue within the chamber and apply an electrical signal to the myocardial tissue within the chamber.

[0008] In an additional embodiment, the ridge includes a drawn metal strip, which may be made of a nickel-titanium alloy. Alternatively, the ridge may include a flexible printed circuit board bonded to a structural member.

[0009] In the embodiments disclosed in this invention, the bipolar pulses applied by the electrical signal generator comprise a sequence of bipolar pulses having an amplitude of at least 200V, and the duration of each bipolar pulse is less than 20μs. Alternatively, the bipolar pulse sequence comprises multiple pairs of pulses, each pair comprising a positive pulse and a negative pulse.

[0010] In some implementations, the electrical signal generator is configured to apply a bipolar pulse between a first set of ridges and a second set of ridges, wherein at least one of the sets includes two or more ridges.

[0011] In another embodiment, the device includes a controller configured to transmit control signals to an electrical signal generator, wherein the electrical signal generator includes a pulse generation component configured to receive the control signals from the controller and, in response to the control signals, transmit a bipolar pulse sequence having amplitude and duration. The electrical signal generator also includes a pulse routing component comprising a switch of a configurable network configured to receive the control signals from the controller, receive the bipolar pulse sequence from the pulse generation component, and, in response to the received control signals, select multiple sets of ridges, each set including one or more ridges, for transmitting the bipolar pulse sequence through the selected set.

[0012] According to an embodiment of the invention, a method for medical use is further provided, comprising inserting a basket-shaped assembly comprising a plurality of resilient conductive ridges into a patient’s body cavity such that the ridges contact tissue within the body cavity, and applying a bipolar pulse between two or more groups of ridges having an amplitude sufficient to induce irreversible electroporation (IRE) in the tissue contacted by the ridges, each group comprising one or more ridges.

[0013] The invention will be more fully understood through the following detailed description of embodiments thereof, taken in conjunction with the accompanying drawings, wherein: Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a system used in IRE ablation surgery according to an embodiment of the present invention;

[0015] Figure 2a A schematic side view of a basket-shaped assembly according to an embodiment of the present invention;

[0016] Figure 2b and Figure 2c A schematic cross-sectional view of the ridge in a basket assembly according to two embodiments of the present invention;

[0017] Figure 3a and Figure 3b A schematic side view of a basket assembly in a collapsed state and an expanded state, respectively, according to an alternative embodiment of the present invention;

[0018] Figure 4 A schematic diagram of a bipolar IRE pulse according to an embodiment of the present invention;

[0019] Figure 5 This is a schematic diagram of the bursting of a bipolar pulse according to an embodiment of the present invention; and

[0020] Figure 6 A block diagram illustrating an IRE module according to an embodiment of the present invention is shown schematically. Detailed Implementation

[0021] Overview

[0022] IRE is primarily a non-thermal process, resulting in a slight increase in tissue temperature of a few degrees Celsius within seconds. Therefore, it differs from RF (radiofrequency) ablation, which raises tissue temperature by 20°C to 70°C and destroys cells through heating. IRE utilizes bipolar pulses, a combination of positive and negative pulses, to avoid muscle contraction due to direct current voltage. The pulses are applied between two bipolar electrodes, such as those in a catheter. Typically, the electrodes are relatively small to achieve localized IRE within the tissue. However, using small electrodes reduces the size of the electroporation area.

[0023] The embodiments of the invention described herein address the problem of increasing the electroporation area by providing a basket-shaped conduit with conductive ridges that contact tissue in a body cavity, such as myocardial tissue in the heart. Each ridge acts as an electrode, and an electrical signal generator applies a bipolar pulse between one or more pairs of ridges, the bipolar pulse having an amplitude sufficient to induce IRE in the tissue contacted by the ridge. Multiple pairs of ridges are selected according to the area to be electroporated, and pulses are applied through multiple pairs of ridges. Using an entire ridge as an electrode in this way allows for simultaneous electroporation of a relatively large area.

[0024] Alternatively, a group of multiple ridges can be electrically connected together to form a larger “virtual electrode.” An IRE signal can be applied between one or more pairs of these “virtual electrodes” or groups.

[0025] A catheter having an expandable basket assembly according to an embodiment of the invention is typically inserted into the heart through a narrow sheath, with the basket assembly in a collapsed state. For deployment in a body cavity, the basket assembly protrudes from the sheath and expands to its operational state. In some embodiments, the ridge is made of an elastic material and is manufactured to bend outwards into a basket shape upon release from the sheath. The catheter may include a pusher tube located within the insertion cannula of the catheter. This pusher tube can be pushed distally at the end of the ablation procedure to straighten the ridge, thereby collapsing the basket assembly so that it can be pulled back into the sheath, facilitating catheter removal from the subject.

[0026] In other embodiments, the ridge is manufactured such that the basket assembly is stable in a collapsed state rather than an inflated state. A puller, passing through the insertion cannula, is attached to the distal end of the basket assembly. After the basket assembly is exposed from the sheath within the body cavity, pulling the puller causes the assembly to inflate from its stable collapsed state to its inflated state, thus enabling its deployment. By releasing the puller, the basket assembly returns to its collapsed state and can be pulled back into the insertion cannula for removal from the subject. This configuration is advantageous because the puller is typically thinner and more flexible than the actuator tube, thus allowing the catheter to be manufactured thinner and more flexible. The puller may comprise, for example, a simple cord or a more complex assembly, such as a polymer tube with braided or embedded cords to minimize elongation.

[0027] System Description

[0028] Figure 1 This is a schematic illustration of a system 20 used in an IRE ablation procedure according to an embodiment of the present invention. (In the following description, the IRE ablation procedure will also be referred to as "IRE ablation" or "IRE procedure".) In the illustrated embodiment, a physician 22 uses system 20 to perform an IRE ablation procedure in the heart 23 of a subject 24. The physician 22 is performing the procedure using an ablation catheter 26 comprising an insertion cannula 28 with a longitudinal axis 27, wherein the distal end 29 of the insertion cannula is connected to a basket assembly 31 comprising a plurality of conductive ridges 30 (in... Figure 2a , Figure 2b and Figure 2c (This is shown in more detail below).

[0029] IRE system 20 includes processor 32 and IRE module 34. IRE module 34 includes IRE generator 36 and IRE controller 38, wherein the IRE generator includes a dedicated pulse generator, as described in detail below. IRE generator 36 generates IRE signals, which consist of bipolar electrical pulse trains, under the control of IRE controller 38. The pulses are directed to a selected ridge 30, which serves as an electrode for performing the IRE procedure. Processor 32 handles the input and output interfaces between IRE system 20 and physician 22, as well as communication with IRE controller 38. References below... Figure 4 and Figure 5 The bipolar electrical pulse and IRE module 34 are further described.

[0030] Processor 32 and IRE controller 38 typically each include a programmable processor programmed in software and / or firmware to perform the functions described herein. Alternatively or additionally, each of them may include hard-wired and / or programmable hardware logic circuitry to perform at least some of these functions. IRE generator 36 includes analog and digital components and elements for generating IRE signals relating to ridge 30. Although processor 32, IRE generator 36, and IRE controller 38 are shown in the accompanying drawings, for simplicity, they are represented as separate monolithic functional blocks; in reality, some of these functions may be combined in a single processing and control unit.

[0031] Processor 32 and IRE module 34 are typically located within console 40. Console 40 includes input devices 42, such as a keyboard and mouse. Display screen 44 is located adjacent to (or integrated with) console 40. Display screen 44 may optionally include a touchscreen, thus providing another input device.

[0032] IRE system 20 may additionally include one or two of the following modules (typically located within console 40) that connect to suitable interfaces and devices within system 20:

[0033] • An electrocardiogram (ECG) module 46 is coupled via a cable 48 to an ECG electrode 50 attached to the subject 24. The ECG module 46 is configured to measure the electrical activity of the heart 23.

[0034] The tracking module 52 is coupled to one or more electromagnetic position sensors 54, which may also be located within the basket assembly 31, in the presence of an external magnetic field generated by one or more magnetic field generators 56. In the presence of such an external magnetic field, the electromagnetic position sensors 54 output signals that vary with the sensor's position. Based on these signals, the tracking module 52 tracks the position of the spine 30 within the heart 23.

[0035] Modules 46 and 52 typically include both analog and digital components and are configured to receive analog signals and transmit digital signals. Each module may additionally include hardwired and / or programmable hardware logic circuitry that performs at least some of the module's functions.

[0036] The conduit 26 is coupled to the control console 40 via an electrical interface 58 (such as a port or socket). Therefore, IRE signals are transmitted from the IRE generator 36 via interface 58 and wired within the insertion tube 28 to the ridge 30 in the basket assembly 31. Similarly, the tracking module 52 can receive signals via interface 58 for tracking the position and orientation of the distal end 28.

[0037] External electrode 60, or “return patch,” may be additionally externally coupled between subject 24 (typically on the skin of the subject’s torso) and IRE module 34. External electrode 60 may be used to couple IRE signals between one of the ridges 30 and the external electrode, thereby enabling electroporation located deeper within tissue 62.

[0038] Before and / or during IRE surgery, processor 32 receives setup parameters 66 for the procedure from physician 22 (or from another user). Using one or more suitable input devices 42, physician 22 sets the setup parameters 66 to select one or more pairs of ridges 30 as electrodes for activation (for receiving IRE signals) and to select the order of activation of the electrodes, as well as defining the characteristics (timing and amplitude) of the IRE signal. Additionally, processor 32 may display the setup parameters 66 on display screen 26. As used herein, multiple pairs of ridges are not limited to adjacent ridges, but rather to all possible configurations that allow biphasic energy to be delivered between two single ridges that act as two separate electrodes (a) or between two sets of multiple ridges (b). For case (a), an example of two singular ridges acting as an electrode “pair” in (a) is ridge 30a adjacent to ridge 30b in Figure 2, defining a “pair of electrodes” when biphasic voltage is delivered to these ridges 30a and 30b. Alternatively, ridge 30a can be paired with a non-adjacent ridge 30c to form "another pair"; ridge 30a can be paired with a non-adjacent ridge 30d to form yet another "pair"; ridge 30a can be paired with a distal ridge 30f to form another "pair"; and ridge 30b can be paired with a distal ridge 30d to form yet another "pair". In another form of case (a), ridges 30a and 30c can be energized as an "electrode pair", and ridges 30b and 30d can be energized as different "electrode pairs", and so on in various arrangements. In the case (b) involving the cooperation of a set of ridges acting as one electrode with another set of different ridges acting as another electrode to achieve a “pair of electrodes,” two or more ridges (e.g., 30a and 30b) may act as one electrode to operate together with two or more ridges (30c and 30d) combined together as another electrode to define an “electrode pair” for delivering biphasic energy to the electrodes (i.e., ridges 30a and 30b as one electrode and ridges 30c and 30d as another electrode to define an “electrode pair”). Various arrangements of a single ridge acting as a pair of electrodes may be combined with multiple sets of ridges acting as an electrode pair, and such combinations are considered to be within the scope of the invention. For example, the ridges shown in FIG2 may be used to define two electrode pairs: ridges 30a and 30b define one electrode pair, and a set of ridges 30c+30d (one electrode) and another set of ridges 30e+30f (as another electrode) define a second electrode pair in FIG2 (i.e., 30a+30b, as the first pair of electrodes; 30c and 30d+30e and 30f as the second pair of electrodes).

[0039] In some implementations, the processor 32 displays relevant images 68 of the subject's anatomy, such as diagrams of the chambers of the heart 23, on a display 44 based on signals received from the tracking module 60. These relevant images are annotated, for example, to show the current position and orientation of the basket assembly 31. Alternatively or additionally, the processor 32 may display the electrical activity of the heart 23 on the display 44 based on signals received from the ECG module 46.

[0040] To begin the procedure, the physician 22 inserts catheter 26, for example, through the subject's vascular system into the subject 24, and then uses control handle 70 to navigate insertion tube 28 to the appropriate site inside or outside the heart 23. During insertion and navigation, basket assembly 31 is typically collapsed within a sheath (not shown) for easy insertion into the subject 24.

[0041] Once the insertion cannula 28 is positioned in the required area within the heart 23, the basket assembly 31 is advanced from the sheath, presenting an expanded form. A further detailed description of the basket assembly 31 is given in Figure 2 below. As schematically shown in Illustration 71, the physician 22 now brings the basket assembly 31 into contact with the tissue 62 of the heart 23 (such as myocardial or epicardial tissue). Next, the IRE generator 36, under the control of the IRE controller 38, generates an IRE signal comprising a pulse train (shown in detail in...). Figure 5 (In the middle). The IRE signal is transmitted through different corresponding electrical conductors (not shown) through the conduit 26 to the paired ridges 30, such that the current 72 generated by the IRE signal flows between each pair of ridges (bipolar ablation), and performs the desired irreversible electroporation of tissue 62 over the extended region between the ridges.

[0042] Figure 2a This is a schematic side view of a basket assembly 31 according to an embodiment of the present invention. The basket assembly 31 includes ridges 30, which are individually labeled 30a, 30b, 30c, 30d, 30e, and 30f in FIG. 2. Ridges 30a to 30f include long segments of elastic material that are conductive or have a conductive coating or conductive member attached thereto. For example, ridges 30a to 30f may comprise a nickel-titanium alloy known as nitinol.

[0043] The proximal ends 74 of ridges 30a to 30f are mechanically engaged at the proximal end 76 of basket assembly 31, and the distal ends 78 of the ridges are mechanically engaged at the distal end 80 of basket assembly. (However, the proximal ends 74 and distal ends 78 of ridges 30a to 30f are electrically insulated from each other, allowing the ridges to be used as separate electrodes.) Ribs 30a to 30f are manufactured such that basket assembly 31 has an expanded state as its stable state. Therefore, when basket assembly is deployed in a body cavity, ridges 30a to 30f bend radially outward, thereby contacting tissue 62 in the body cavity. Ribs 30a to 30f are electrically coupled to IRE generator 36 via conductors within conduit 26. Figure 1 () is used to receive IRE ablation signals.

[0044] The IRE signal received from IRE generator 36 is coupled between, for example, ridges 30a and 30b, resulting in electroporation between these two ridges. Due to the applied IRE signal, current 72 ( Figure 1 The flow extends along the entire length of ridges 30a and 30b, between them, thereby inducing electroporation over a larger area in tissue 62. For example, applying basket assembly 31 to pulmonary vein ablation will induce electroporation over a ring 6 mm to 12 mm wide around the pulmonary vein.

[0045] The IRE signal can be coupled between any pair of ridges 30a to 30f, but typically the signal will be applied between multiple pairs of adjacent ridges. Alternatively, the signal can be applied simultaneously or alternately between several pairs of ridges. Although the basket assembly 31 is shown in Figure 2 as comprising six ridges, other numbers of ridges, less than and greater than six, may also be used. Alternatively, a group of multiple ridges 30 can be electrically connected together to form a larger “virtual electrode” comprising multiple ridges. The IRE signal can be applied between one or more pairs of these “virtual electrodes” or groups.

[0046] Figure 2b and Figure 2c This is a schematic cross-sectional view of the ridge 30 according to two embodiments of the present invention.

[0047] Figure 2b This is a schematic cross-sectional view of ridge 30, which includes drawn nitinol strip 33. The nitinol strip 33 serves both as a structural member of ridge 30 and as an electrical conductor for current 72. Figure 1 It is advantageous to form the nitinol strip 33 by a drawing process because the resulting strip has rounded edges 35 (as opposed to the sharp edges formed in a strip cut from a nitinol sheet), thus avoiding damage to the tissue 62 that is in contact with the ridge 30.

[0048] Figure 2c The diagram shows a schematic cross-sectional view of ridge 30 in an alternative embodiment, where ridge 30 comprises a composite of structural member 37 and conductive member 39. Structural member 37 includes, for example, […]. Figure 2b The drawn nitinol tape is shown. The conductive member 39 includes a conductive film (such as gold) disposed on a flexible printed circuit board (PCB) 41, which is then bonded to the structural member 37 using a suitable adhesive and insulating material 43 (such as a biocompatible epoxy resin or other adhesive). Thus, the structural member 37 is insulated from the tissue 62, and the current 72 is conducted to the tissue through the conductive member 39 exposed to the tissue.

[0049] Alternatively, ridge 30 may include a conductive or non-conductive structural member having a conductive coating (not shown).

[0050] Figure 3a and Figure 3b A schematic side view of a basket assembly 90 in a collapsed state and an expanded state, respectively, according to an alternative embodiment of the present invention. Figure 1The same numerical markings as in Figure 2 are used Figure 3a and Figure 3b Similar projects in [the context]. For example... Figure 2a , Figure 3a and Figure 3b In the middle, the ridge 30 includes a long section of elastic material, which is conductive or has a conductive coating or conductive component attached thereto.

[0051] Figure 3a A basket assembly 90 in a collapsed state is shown, with the ridge 30 straight and aligned parallel to the longitudinal axis 27. This is the stable state of the basket assembly 90: when it is pushed out of the sheath, the assembly 90 remains in the collapsed state unless forced into an expanded state. The ablation catheter 26 contains a retractor 92 that extends through the insertion tube 28 and is capable of longitudinal movement within the insertion tube 28. The retractor 92 has a distal end 94 attached to the distal end 80 of the basket assembly 90 and a proximal end (not shown) attached to the control handle 70. Since the proximal end 74 of the ridge 30 is secured to the insertion tube 28, pulling the retractor 92 from its proximal end shortens the distance between the corresponding distal end 78 and proximal end 74 of the ridge 30, resulting in the ridge bending outward for deployment, as... Figure 3b As shown. Due to the elasticity of the ridge 30, the release tensioner 92 allows the basket assembly 90 to collapse back to its stable state. Figure 3a ), so that catheter 26 can be removed from subject 24.

[0052] The puller 92 may include any suitable elongated component with sufficient tensile strength and bending flexibility. For example, the puller 92 may include a simple wire. Alternatively, the puller 92 may include a more complex structure, such as a polymer tube with reinforcements in the form of braided or embedded wires, to minimize its elongation.

[0053] Figure 5 This is a schematic diagram of a bipolar IRE pulse 100 according to an embodiment of the present invention.

[0054] Curve 102 shows the voltage V of the bipolar IRE pulse 100 as a function of time t during IRE ablation. The bipolar IRE pulse 100 includes a positive pulse 104 and a negative pulse 106, where the terms "positive" and "negative" refer to the arbitrary polarity of the two ridges 30 of the bipolar pulse applied therebetween. The amplitude of the positive pulse 104 is denoted as V+, and the pulse's duration is denoted as t+. Similarly, the amplitude of the negative pulse 106 is denoted as V-, and the pulse's duration is denoted as t-. The duration between the positive pulse 104 and the negative pulse 106 is denoted as t. 间隔 Typical values ​​for the parameters of the bipolar pulse 100 are given in Table 1 below.

[0055] Figure 5This is a schematic diagram of a bipolar pulse burst 200 according to an embodiment of the present invention.

[0056] During IRE surgery, the IRE signal is delivered to the spine 30 as one or more bursts 200, as shown by curve 202. The bursts 200 include N... T There are 204 pulse trains, each consisting of N pulses. P One bipolar pulse 100. The length of the pulse train 204 is marked as t. T The period of the bipolar pulse 100 within pulse train 204 is denoted as t. PP The interval between consecutive strings is marked as Δ. T No signal is applied during this interval. Typical values ​​for the parameters of burst 200 are given in Table 1 below.

[0057] Table 1: Typical values ​​of IRE signal parameters

[0058]

[0059] Figure 6 A block diagram illustrating details of the IRE module 34 according to an embodiment of the present invention. As stated above regarding... Figure 1 As explained, IRE module 34 includes an IRE generator 36 and an IRE controller 38. IRE generator 36 includes a pulse generation component 406 and a pulse routing component 408. Pulse generation component 406 is configured to receive control signals from IRE controller 38 (described below) and, in response to the control signals, transmit a bipolar pulse sequence having amplitude and duration. Pulse routing component 408 includes a configurable network switch configured to receive control signals from IRE controller 38, receive the bipolar pulse sequence from pulse generation component 405, and, in response to the received control signals, select multiple pairs of ridges 30 to transmit the bipolar pulse sequence through the selected pairs.

[0060] IRE controller 38 communicates with processor 32 via bidirectional signal 410, whereby the processor transmits commands reflecting setting parameters 66 to the IRE controller. IRE controller 38 further transmits digital command signals 418 derived from setting parameters 66 to pulse generation component 406, thereby commanding IRE generator 36 to generate IRE pulses, such as those described above. Figure 4 Those shown in the diagram. These IRE pulses are sent as analog pulse signals 420 to the pulse routing component 408, as instructed by the IRE controller 38.

[0061] Pulse routing component 408 is coupled to ridge 30 via output channel 422 and (optionally) to return patch 60 via connection 424. For example, when pulse routing component 408 is coupled to the six ridges 30a to 30f (FIG. 2) of basket assembly 31, the six output channels in output channel 422 are coupled to the ridges. Pulse routing component 408 is driven by IRE controller 38 to couple IRE pulses to the ridges 30, as defined by setting parameter 66. Specifically, IRE controller 38 drives pulse routing component 408 to couple IRE pulses to one or more pairs of selected ridges 30. Routing component 408 can also electrically couple multiple ridges 30 together to form a group that can be used as a “virtual electrode.” Thus, IRE controller 38 controls the generation and routing of IRE pulses to the ridges 30.

[0062] although Figure 6 Ten channels 422 are shown, but the IRE generator 36 may optionally include a different number of channels, such as 8, 16 or 20 channels, or any other suitable number of channels.

[0063] It should be understood that the above embodiments are cited by way of example, and the invention is not limited to the specific contents shown and described above. Rather, the scope of the invention includes combinations and sub-combinations of the various features described above, as well as variations and modifications thereof, which should be apparent to those skilled in the art upon reading the above description, and which are not disclosed in the prior art.

Claims

1. A medical device comprising: The probe includes: An insertion tube, configured for insertion into a patient's body cavity; and A basket-shaped assembly, distally connected to the insertion tube and including a plurality of conductive ridges, each of the plurality of conductive ridges forming an electrode along the entire length of the ridge and configured to contact tissue within the body; and An electrical signal generator is configured to apply bipolar pulses between one or more pairs of the plurality of conductive ridges, the bipolar pulses having an amplitude sufficient to induce irreversible electroporation (IRE) in the tissue contacted by the ridges.

2. The device of claim 1, wherein the ridge has a corresponding proximal end and a distal end, wherein the proximal end of the ridge is mechanically engaged at the proximal end of the basket assembly, and the distal end of the ridge is mechanically engaged at the distal end of the basket assembly, and the ridge bends radially outward when the basket assembly is deployed in the body cavity to contact the tissue in the body cavity.

3. The device of claim 2, wherein the basket assembly has a stable collapsed state, and wherein the device includes a puller attached to the distal end of the basket assembly and slidably disposed within the insertion tube, such that the ridge bends radially outward in response to pulling the puller through the insertion tube in a proximal direction.

4. The device of claim 3, wherein the puller comprises a reinforced polymer tube.

5. The device of claim 1, wherein the insertion tube comprises a catheter configured for insertion into a chamber of the patient's heart, and the ridge is configured to contact myocardial tissue within the chamber and apply an electrical signal to the myocardial tissue within the chamber.

6. The device according to claim 1, wherein the ridge comprises a drawn metal strip.

7. The device of claim 6, wherein the metal strip comprises a nickel-titanium alloy.

8. The device of claim 1, wherein the ridge comprises a flexible printed circuit board bonded to a structural member.

9. The device of claim 1, wherein the bipolar pulse applied by the electrical signal generator comprises a sequence of bipolar pulses having an amplitude of at least 200V, and the duration of each bipolar pulse in the bipolar pulses is less than 20µs.

10. The device of claim 9, wherein the bipolar pulse sequence comprises multiple pairs of pulses, wherein each pair comprises a positive pulse and a negative pulse.

11. The device of claim 1, wherein the electrical signal generator is configured to apply the bipolar pulse between a first group of the ridges and a second group of the ridges, wherein at least one of the first group and the second group includes two or more of the ridges.

12. The device of claim 1, further comprising a controller configured to transmit control signals to the electrical signal generator, wherein the electrical signal generator comprises: A pulse generation component configured to receive the control signal from the controller and, in response to the control signal, transmit a bipolar pulse sequence having amplitude and duration; and A pulse routing component, comprising a configurable network switch configured to receive control signals from the controller, receive the bipolar pulse sequence from the pulse generation component, and, in response to the received control signals, select multiple sets of the ridges, each set including one or more of the ridges, for transmitting the bipolar pulse sequence through the selected sets.

Images