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US-12616517-B2 - Expandable basket assemblies with linear spine patterns for improved tissue contact and methods for making thereof

US12616517B2US 12616517 B2US12616517 B2US 12616517B2US-12616517-B2

Abstract

The disclosed technology includes an expandable basket assembly for a medical probe, which may include a single unitary structure including a plurality of spines converging at a central spine intersection. The central spine intersection being positioned on a longitudinal axis of the expandable basket assembly at a distal end thereof. The single unitary structure may include a plurality of radial cutouts with each radial cutout defining an opening in each of the plurality of spines proximate the central spine intersection so that each opening extends for a length along each spine away from the central spine intersection.

Inventors

  • Kevin Mark Okarski
  • Keshava Datta
  • Abubakarr BAH
  • Thanh Nguyen

Assignees

  • BIOSENSE WEBSTER (ISRAEL) LTD.

Dates

Publication Date
20260505
Application Date
20230224

Claims (19)

  1. 1 . An expandable basket assembly for a medical probe, comprising: a single unitary structure comprising a plurality of spines converging at a central spine intersection, the central spine intersection being positioned on a longitudinal axis of the expandable basket assembly at a distal end thereof; and a plurality of radial cutouts with each radial cutout defining an opening in each of the plurality of spines proximate the central spine intersection so that each opening extends for a length along each spine away from the central spine intersection, each cutout comprises a tadpole shaped cutout, the tadpole shaped cutout includes a head portion contiguous to a circumference of a first virtual circle with a first radius r 1 disposed about the longitudinal axis, the head portion defining a negative area approximating a second virtual circle with a second radius r 2 , the head portion connected to a slotted tail portion extending for a first length L 1 along the spine and contiguous to an inside circumference of a third virtual circle having a third radius r 3 , and the first length of the slotted tail portion is approximately 6-10 times that of the length of the first radius r 1 of the first virtual circle.
  2. 2 . The expandable basket assembly according to claim 1 , further comprising a center aperture disposed on the central spine intersection, wherein the plurality of radial cutouts are separated from the center aperture by a portion of the central spine intersection.
  3. 3 . The expandable basket assembly of claim 1 , further comprising a center cutout disposed on the longitudinal axis to define a central negative area of a center aperture approximating a central circle including a central radius r 0 smaller than the first radius r 1 .
  4. 4 . The expandable basket assembly of claim 3 , in which the negative area of each of the tadpole shaped cutouts comprises approximately 0.2 mm-squared while the negative area of the center aperture is approximately 0.05 mm-squared so that a total negative area defined by all of the cut outs is approximately 1.4 mm-squared.
  5. 5 . The expandable basket assembly of claim 3 , wherein central void radius r 0 comprises approximately 0.13 mm, the second radius r 2 comprises approximately 0.2 mm, and the first radius r 1 comprises approximately 0.23 mm.
  6. 6 . An expandable basket assembly for a medical probe, comprising: a single unitary structure comprising a plurality of spines converging at a central spine intersection, the central spine intersection being positioned on a longitudinal axis of the expandable basket assembly at a distal end thereof; a plurality of radial cutouts with each radial cutout defining an opening in each of the plurality of spines proximate the central spine intersection so that each opening extends for a length along each spine away from the central spine intersection, and a center aperture disposed on the central spine intersection, wherein the plurality of radial cutouts are separated from the center aperture by a portion of the central spine intersection, the center aperture comprises an area of about 0.01 mm-squared to about 0.4 mm-squared, each of the plurality of radial cutouts includes an area of about 0.1 mm-squared to about 0.55 mm-squared and each of the spines includes a first portion proximate to the central spine intersection with a first width, a second portion proximate the first portion with a second width less than the first portion, and a third portion proximate the second portion with a third width that is greater than the first width and greater than the second width, each of the plurality of radial cutouts defines a comet-shaped cutout with head portion with a slotted tapered tail extending to a proximal portion of each spine.
  7. 7 . The expandable basket assembly according to claim 6 , wherein the first width is about 0.15 mm to about 0.5 mm, the second width is about 0.05 mm to about 0.35 mm, and the third width is about 0.3 mm to about 0.7 mm, and the third portion of each spine comprises an electrode attachment slot configured to accept an electrode, the electrode attachment slot bisects each spine into two minor widths of about 0.05 mm to about 6 mm.
  8. 8 . An expandable basket assembly for a medical probe, comprising: a single unitary structure comprising a plurality of spines converging at a central spine intersection, the central spine intersection being positioned on a longitudinal axis of the expandable basket assembly at a distal end thereof; and a plurality of radial cutouts with each radial cutout defining an opening in each of the plurality of spines proximate the central spine intersection so that each opening extends for a length along each spine away from the central spine intersection, a center aperture disposed on the central spine intersection, wherein the plurality of radial cutouts are separated from the center aperture by a portion of the central spine intersection, wherein each cut out comprises two teardrop cutouts attached at their narrow portions to define a single cutout on each spine of about 0.4 mm-squared.
  9. 9 . The expandable basket assembly according to claim 6 , wherein the third portion of each spine comprises a slot that bisects each spine into two minor widths each of which comprises a width of approximately 0.1 mm to approximately 6 mm.
  10. 10 . The expandable basket assembly according to claim 6 , wherein the third portion of each spine comprises a slot that bisects each spine into two minor portions with the slot comprising a width of approximately 0.05 mm to approximately 0.55 mm and the center aperture includes a radius of approximately 0.4 mm to approximately 1.2 mm.
  11. 11 . The expandable basket assembly according to claim 8 , wherein each radial cutout comprises an ellipse shape at an end furthest from the center aperture and the ellipse shape includes a length of about 0.20 mm to about 0.55 mm and a width of about 0.1 mm to about 0.45 mm.
  12. 12 . The expandable basket assembly according to claim 1 , further comprising a center aperture disposed on the central spine intersection, wherein the plurality of radial cutouts extend from and are connected to the center aperture to form a single cutout.
  13. 13 . The expandable basket assembly according to claim 1 , each of the spines includes a first portion proximate to the central spine intersection with a first width, a second portion proximate the first portion with a second width less than the first portion, and a third portion proximate the second portion with a third width that is greater than the first width and greater than the second width, wherein the first width is about 0.15 mm to about 0.5 mm, the second width is about 0.05 mm to about 0.35 mm, and the third width is about 0.3 mm to about 0.7 mm.
  14. 14 . The expandable basket assembly according to claim 1 , each of the spines includes a first portion proximate to the central spine intersection with a first width, a second portion proximate the first portion with a second width less than the first portion, and a third portion proximate the second portion with a third width that is greater than the first width and greater than the second width, wherein the third portion of each spine comprises an electrode attachment slot configured to accept an electrode, the electrode attachment slot bisects each spine into two minor widths of about 0.05 mm to about 6 mm.
  15. 15 . The expandable basket assembly according to claim 1 , each of the spines includes a first portion proximate to the central spine intersection with a first width, a second portion proximate the first portion with a second width less than the first portion, and a third portion proximate the second portion with a third width that is greater than the first width and greater than the second width, wherein the third portion of each spine comprises a slot that bisects each spine into two minor widths each of which comprises a width of approximately 0.1 mm to approximately 6 mm.
  16. 16 . The expandable basket assembly according to claim 8 , each of the spines includes a first portion proximate to the central spine intersection with a first width, a second portion proximate the first portion with a second width less than the first portion, and a third portion proximate the second portion with a third width that is greater than the first width and greater than the second width, wherein the first width is about 0.15 mm to about 0.5 mm, the second width is about 0.05 mm to about 0.35 mm, and the third width is about 0.3 mm to about 0.7 mm.
  17. 17 . The expandable basket assembly according to claim 8 , each of the spines includes a first portion proximate to the central spine intersection with a first width, a second portion proximate the first portion with a second width less than the first portion, and a third portion proximate the second portion with a third width that is greater than the first width and greater than the second width, wherein the third portion of each spine comprises an electrode attachment slot configured to accept an electrode, the electrode attachment slot bisects each spine into two minor widths of about 0.05 mm to about 6 mm.
  18. 18 . The expandable basket assembly according to claim 8 , each of the spines includes a first portion proximate to the central spine intersection with a first width, a second portion proximate the first portion with a second width less than the first portion, and a third portion proximate the second portion with a third width that is greater than the first width and greater than the second width, wherein the third portion of each spine comprises a slot that bisects each spine into two minor widths each of which comprises a width of approximately 0.1 mm to approximately 6 mm.
  19. 19 . The expandable basket assembly according to claim 8 , each of the spines includes a first portion proximate to the central spine intersection with a first width, a second portion proximate the first portion with a second width less than the first portion, and a third portion proximate the second portion with a third width that is greater than the first width and greater than the second width, wherein the third portion of each spine comprises a slot that bisects each spine into two minor portions with the slot comprising a width of approximately 0.05 mm to approximately 0.55 mm.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims priority under 35 U.S.C. § 119 to U.S. Provisional Patent Application No. 63/323,849, filed Mar. 25, 2022, the entire contents of which are incorporated herein by reference. FIELD The present invention relates generally to medical devices, and in particular catheters with expandable basket assemblies and electrodes, and further relates to, but not exclusively, catheters suitable for use to induce irreversible electroporation (IRE) of cardiac tissues. BACKGROUND Cardiac arrhythmias, such as atrial fibrillation (AF), occur when regions of cardiac tissue abnormally conduct electric signals to adjacent tissue. This disrupts the normal cardiac cycle and causes asynchronous rhythm. Certain procedures exist for treating arrhythmia, including surgically disrupting the origin of the signals causing the arrhythmia and disrupting the conducting pathway for such signals. By selectively ablating cardiac tissue by application of energy via a catheter, it is sometimes possible to cease or modify the propagation of unwanted electrical signals from one portion of the heart to another. Many current ablation approaches in the art tend to utilize radiofrequency (RF) electrical energy to heat tissue. RF ablation can have certain rare drawbacks due to operator's skill, such as heightened risk of thermal cell injury which can lead to tissue charring, burning, steam pop, phrenic nerve palsy, pulmonary vein stenosis, and esophageal fistula. Cryoablation is an alternative approach to RF ablation that generally reduces thermal risks associated with RF ablation but may present tissue damage due to the very low temperature nature of such devices. Maneuvering cryoablation devices and selectively applying cryoablation, however, is generally more challenging compared to RF ablation; therefore cryoablation is not viable in certain anatomical geometries which may be reached by electrical ablation devices. Some ablation approaches use irreversible electroporation (IRE) to ablate cardiac tissue using nonthermal ablation methods. IRE delivers short pulses of high voltage to tissues and generates an unrecoverable permeabilization of cell membranes. Delivery of IRE energy to tissues using multi-electrode catheters was previously proposed in the patent literature. Examples of systems and devices configured for IRE ablation are disclosed in U.S. Patent Pub. Nos. 2021/0169550A1, 2021/0169567A1, 2021/0169568A1, 2021/0161592A1, 2021/0196372A1, 2021/0177503A1, 2021/0186604A1, 2021/0162210, and 2021/0077180, each of which are incorporated herein by reference and attached in the Appendix of parent application 63/323,849. Regions of cardiac tissue can be mapped by a catheter to identify the abnormal electrical signals. The same or different catheter can be used to perform ablation. Some example catheters include a number of spines with electrodes positioned thereon. The electrodes are generally attached to the spines and secured in place by soldering, welding, or using an adhesive. Furthermore, multiple linear spines are generally assembled together by attaching both ends of the linear spines to a tubular shaft (e.g., a pusher tube) to form a spherical basket. Due to the small size of the spines and the electrodes, however, adhering the electrodes to the spines and then forming a spherical basket from the multiple linear spines can be a difficult task, increasing the manufacturing time and cost and the chances that the electrode fails due to an improper bond or misalignment. What is needed, therefore, are devices and methods of forming an improved basket assembly that can help to reduce the time required for manufacturing the basket assembly and alternative catheter geometries in general. SUMMARY Various embodiments of an expandable basket assembly for a medical probe and related methods are described and illustrated. An expandable basket assembly for a medical probe may include a single unitary structure comprising a plurality of spines converging at a central spine intersection. The central spine intersection may be positioned on a longitudinal axis of the expandable basket assembly at a distal end thereof. The single unitary structure may include a plurality of radial cutouts with each radial cutout defining an opening in each of the plurality of spines proximate the central spine intersection so that each opening extends for a length along each spine away from the central spine intersection. Each cut-out may include a tadpole shaped cutout. The tadpole cutout may include a head portion contiguous to a circumference of a first virtual circle with a first radius r1 disposed about the central axis. The head portion may define a negative area approximating a second virtual circle with a second radius r2. The head portion may be connected to a slotted tail portion extending for a first length L1 along the spine and contiguous to an inside circumference of a third virtual circle having a third