EP-4734862-A1 - ROTATIONAL ATHERECTOMY DEVICES AND METHODS

EP4734862A1EP 4734862 A1EP4734862 A1EP 4734862A1EP-4734862-A1

Abstract

Some embodiments of a rotational atherectomy device can remove (partially or completely) stenotic lesions in blood vessels by rotating one or more abrasive elements in an orbital path to abrade and breakdown the lesion. In particular implementations, multiple abrasive elements are arranged along a distal portion of a drive shaft with an improved configuration so as to facilitate both efficient navigation into smaller blood vessels below the ankle or in the heart and effective orbital paths for abrading stenotic material in such smaller vessels.

Inventors

MUSTAPHA, JIHAD A.
PETRUCCI, GARY M.
BENJAMIN, ALBERT SELDEN
WELTY, RYAN D.

Assignees

Cardio Flow, Inc.

Dates

Publication Date: 20260506
Application Date: 20240626

Claims (20)

1. A rotational atherectomy system for removing stenotic lesion material from a pedal artery or coronary artery of a patient, comprising: a 4-French introducible rotational atherectomy device, comprising: a torque-transmitting coil of one or more filars that are helically wound around in a fdar wind direction from a distal end to a proximal end to define a coil diameter and a drive shaft axis; and a series of abrasive burrs fixedly mounted to a distal end portion of the torquetransmitting coil and having a maximum burr diameter of no greater than 1.25 mm, wherein the series of abrasive burrs includes a distal concentric abrasive burr coaxially mounted to a distal-most end of the torquetransmitting coil, a proximal concentric abrasive burr having the same size as the distal concentric abrasive burr and being coaxially mounted to the torque-transmitting coil at a position no greater than 0.5-inches from the distal-most end of the torque-transmitting coil, and an intermediate eccentric abrasive burr having a larger size than the distal and proximal concentric abrasive burrs and being mounted the torque-transmitting coil with a center of mass offset from the drive shaft axis; and a rotational atherectomy handle assembly coupled to a proximal end of the torquetransmitting coil and housing an electric motor configured to, responsive to user input at an actuator of the rotational atherectomy handle assembly, drive rotation of the series of abrasive burrs about the drive shaft axis in a rotational direction.
2. The rotational atherectomy system claim 1, further comprising a sheath that extends from the rotational atherectomy handle assembly and over the torque transmitting coil, wherein the actuator of the rotational atherectomy handle assembly is configured to longitudinally adjust the torque-transmitting coil relative to the sheath such that, in a proximal position, the series of abrasive burrs are housed within a distal-most end of the sheath.
3. The rotational atherectomy system of claim 2, wherein responsive to distal longitudinal movement of the actuator of the rotational atherectomy handle, the series of abrasive burrs are adjusted to a distal position so as to extend distally from the distal-most end of the sheath.
4. The rotational atherectomy system of claim 3, wherein the electric motor housed within the rotational atherectomy handle is prevented from rotating the torquetransmitting coil when the series of abrasive burrs are in the proximal position and housed within the distal-most end of the sheath.
5. The rotational atherectomy system of claim 4, wherein when the series of abrasive burrs are adjusted to the distal position to extend distally from the distal-most end of the sheath, a switch that is housed within the rotational atherectomy handle is triggered and the electric motor is selectively activatable to drive rotation of the series of abrasive burrs.
6. The rotational atherectomy system of claim 5, wherein when the actuator of the rotational atherectomy handle assembly is adjusted to a location proximal of a threshold position along an upper face of the rotational atherectomy handle assembly, the series of abrasive burrs are in the proximal position and housed within the distal-most end of the sheath.
7. The rotational atherectomy system of claim 6, wherein when the actuator of the rotational atherectomy handle assembly is adjusted to a location distal of the threshold position along the upper face of the rotational atherectomy handle assembly, the series of abrasive burrs are in the distal position and extend distally from the distal-most end of the sheath.
8. The rotational atherectomy system of claim 1, wherein the torque-transmitting coil has an outer coil diameter and each abrasive burr in the series of abrasive burrs has a respective burr diameter, wherein burr-to-coil diameter ratio defined by each respective burr diameter and the outer coil diameter is about 1.3- 1.7.
9. The rotational atherectomy system of claim 1, wherein a diameter of the proximal concentric abrasive burr is equal to the diameter of the distal concentric abrasive burr, and the diameter of the proximal and distal concentric abrasive burrs is less than a diameter of the intermediate eccentric abrasive burr.
10. The rotational atherectomy system of claim 9, wherein a diameter of the intermediate eccentric abrasive burr is 1.25 mm and a diameter of each of the proximal and distal concentric abrasive burrs is 1.1 mm.
11. The rotational atherectomy system of claim 10, wherein each abrasive burr of the series of abrasive burrs is a spherical metallic burr coated with diamond grit.
12. The rotational atherectomy system of claim 1, wherein the electric motor housed within the rotational atherectomy handle is configured to rotate the torque-transmitting coil so that the series of abrasive burrs orbit in the rotational direction opposite of the filar wind direction.
13. A method for rotational atherectomy in a pedal artery below an ankle, comprising: advancing a torque-transmitting coil of a rotation atherectomy device over a guidewire and into a pedal artery below an ankle so that at least one abrasive bunmounted to a distal end portion of the torque-transmitting coil is proximate to a stenotic lesion within the pedal artery; and rotating the torque-transmitting coil of the rotation atherectomy device so that the at least one abrasive burr mounted to the torque-transmitting coil abrades the stenotic lesion within the pedal artery.
14. The method of claim 13, wherein said rotating the torque-transmitting coil comprises manually actuating an actuator of a rotational atherectomy handle assembly to activate an electric motor housed with the rotational atherectomy handle assembly so that the electric motor drives rotation of the at least one abrasive burr in a rotational direction.
15. The method of claim 14, further comprising retracting a sheath positioned over the at least one abrasive burr until the at least one abrasive burr is exposed within the pedal artery.
16. The method of claim 15, wherein the sheath that extends from the rotational atherectomy handle assembly and over the torque transmitting coil, further comprising sliding the actuator of the rotational atherectomy handle assembly along the upper face of the rotational atherectomy handle assembly to longitudinally adjust the torquetransmitting coil relative to the sheath.
17. The method of claim 16, slidably moving the actuator of the rotational atherectomy handle to adjust the at least one abrasive burr from a proximal position in which the at least one abrasive burr is housed within a distal-most end of the sheath to a distal position in which the at least one abrasive burr extends distally from the distal-most end of the sheath.
18. The method of claim 17, wherein the electric motor housed within the rotational atherectomy handle is prevented from rotating the torque-transmitting coil when the at least one abrasive burr is in the proximal position and housed within the distal-most end of the sheath.
19. The method of claim 13, wherein the rotation atherectomy device is a 4-French introducible rotational atherectomy device.
20. The method of claim 19, wherein the at least one abrasive burr comprises a set of three spherical abrasive burrs including a distal-most concentric abrasive burr, an intermediate eccentric abrasive burr, and a proximal-most concentric abrasive burr, wherein the distal-most concentric abrasive burr is mounted directly to a distal-most end of the torque-transmitting coil and the proximal-most concentric abrasive burr is mounted to the torque-transmitting coil at a position no greater than 0.5-inches from the distal- most end of the torque-transmitting coil, wherein a diameter of the proximal-most concentric abrasive burr is equal to the diameter of the distal-most concentric abrasive burr, and wherein the diameter of the proximal-most and distal-most concentric abrasive burrs is less than a diameter of the intermediate eccentric abrasive burr.

Description

ROTATIONAL ATHERECTOMY DEVICES AND METHODS CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Application 18/523,683 filed November 29, 2023, which claims the benefit under 35 U.S.C. § 119 to U.S. Provisional Application Serial No. 63/542,438, filed on October 4, 2023, and to U.S. Provisional Application Serial No. 63/523,583, filed on June 27, 2023, the contents of each of which are incorporated herein by reference in their entirety. TECHNICAL FIELD This document relates to rotational atherectomy devices and systems for removing or reducing stenotic lesions in blood vessels, for example, by urging one or more abrasive elements in an orbital motion within the vessel to remove (partially or completely) the stenotic lesion material. BACKGROUND Atherosclerosis, the clogging of arteries with plaque, is often a result of coronary heart disease or vascular problems in other regions of the body. Plaque can be formed from fat, cholesterol, calcium, and other substances found in the blood. Over time, the plaque hardens and narrows the arteries. This limits the flow of oxygen-rich blood to organs and other parts of the body. Blood flow through the central and peripheral arteries (e g., carotid, iliac, femoral, renal, etc.) can be similarly affected by the development of atherosclerotic blockages. For example, peripheral artery disease (PAD) can be serious because without adequate blood flow, the kidneys, legs, arms, and feet may suffer irreversible damage. Left untreated, the tissue may die or harbor infection. In another example, coronary artery disease (CAD) arises from the buildup of atherosclerotic material in one or more coronary arteries and may result in a deprivation of blood, oxygen, and nutrients to the heart muscle. Rotational atherectomy can be used to treat such blockages in some types of blood vessels. In some versions of rotational atherectomy, a drive shaft carrying an abrasive burr or other abrasive surface (e.g., having diamond grit or diamond particles) rotates at a high speed within the vessel, and the clinician operator slowly advances the atherectomy device distally so that the abrasive burr scrapes against the occluding lesion and grinds it into very small particles, reducing the occlusion and improving blood flow through the vessel. While rotational atherectomy is commonly performed in larger arteries in the leg, such a process can be obstructed in small arteries, such as those below the ankle (e.g., in the feet) or in particular coronary arteries (e.g., in the left anterior descending coronary artery or the left circumflex coronary artery), especially where the vessel interior diameter is often 3 mm or less and the access path follows a tortuous route. SUMMARY Some embodiments of rotational atherectomy systems described herein can remove (partially or completely) stenotic lesions in blood vessels by rotating one or more abrasive elements in an orbital path to abrade and breakdown the lesion. In particular implementations, multiple abrasive elements are arranged along a distal portion of a drive shaft with an improved configuration/relative sizing so as to facilitate both efficient navigation into smaller blood vessels (below the ankle or in the heart) and effective orbital paths for abrading stenotic material in such smaller vessels. Additionally, some versions of the improved configuration of the multiple abrasive elements are arranged along the drive shaft can be effective for the removal or reduction of stenotic lesions in larger vessels too (e.g., those in the leg above the ankle or larger coronary arteries), thereby providing the user with options for efficiently treating a variety of arterial sites during a single procedure. In one aspect, this disclosure is directed to a rotational atherectomy device for removing stenotic lesion material from a pedal artery or coronary artery of a patient. The device can include an elongate flexible drive shaft defining a longitudinal axis and comprising a torque-transmitting coil of one or more filars that are helically wound around the longitudinal axis in a filar wind direction from a distal end to a proximal end. The device may also include one or more abrasive burrs (e.g., such as a series of abrasive burrs as illustrated herein below) fixedly mounted to a distal end portion of the torquetransmitting coil. Optionally, the abrasive burrs can have a maximum burr diameter of no greater than 1.25 mm. At least one of the abrasive burrs can be an eccentric abrasive burr having a center of mass offset from the longitudinal axis so as to orbit in a rotational direction opposite of the filar wind direction. In another aspect, this disclosure describes a method for rotational atherectomy in a pedal artery below an ankle. The method can include advancing a torque-transmitting coil of a rotation atherectomy device over a guidewire and into a pedal artery below an ankle so that at least one abrasive burr mounted to a distal en