89 results about "Rotational atherectomy device" patented technology

The invention provides a rotational atherectomy device having, in various embodiments, a flexible, elongated, rotatable drive shaft with at least one flexible eccentric enlarged abrading head attached thereto. In other embodiments, the eccentric abrading head is not flexible or partially flexible. At least part of the eccentric enlarged cutting head has a tissue removing surface—typically an abrasive surface. In certain embodiments, the abrading head will be at least partially hollow. When placed within an artery against stenotic tissue and rotated at sufficiently high speeds the eccentric nature of the enlarged cutting head causes the cutting head and drive shaft to rotate in such a fashion as to open the stenotic lesion to a diameter substantially larger than the outer diameter of the enlarged cutting head. Preferably the eccentric enlarged cutting head has a center of mass spaced radially from the rotational axis of the drive shaft, facilitating the ability of the device to open the stenotic lesion to a diameter substantially larger than the outer diameter of the enlarged cutting head when operated at high speeds.

A rotational atherectomy device that includes an expandable head that can clean a blockage from vessel larger than its rest diameter, in which the drive shaft may rotate in two opposite directions and may have different abrasive characteristics for each rotation direction. In one direction, the head may be configured for cutting and / or slicing, which may be well suited to removing particularly soft blockage material. In the other direction, the head may be configured for grinding, scraping and / or sanding, which may be well suited to removing particularly hard blockage material. The head includes one or more arms that are pivotally or hingedly attached to the drive shaft. One or more abrasive elements are disposed on or are attached to the one or more arms. The abrasive elements have a cutting feature, such as a sharpened edge that cuts like a razor blade when the drive shaft is rotated in the “cutting” direction. The abrasive elements also have a grinding feature, such as an abrasive material disposed on the abrasive element adjacent to the sharpened edge, which grinds away a blockage when the drive shaft is rotated in the “grinding” direction.

The invention provides a rotational atherectomy system, device and method comprising a flexible, elongated, rotatable drive shaft with a pre-curved abrasive section disposed within a catheter that deforms the abrasive section to a substantially straight profile and, when the abrasive section is moved distally out of the catheter, the abrasive section resumes its pre-curved profile. Directional ablation is achieved by rotation of the drive shaft along its pre-curved axis as the abrasive section is urged against a portion of the lumen wall.

An atherectomy device is disclosed, which is rotationally driven by an electric motor. In some designs, the device includes features unavailable on gas turbine-driven systems, such as the storing in memory of low / medium / high preset rotation speeds for particular models of handle, calculations of the amount of saline left in the IV and associated warnings when it gets sufficiently low, and automatic adjustment of the IV pump rate to a predetermined or calculated level when the rotational speed of the motor is changed. The electric motor has far more rotational inertia than a comparable gas turbine, so the system includes a control mechanism that helps prevent damage from excessive torque being applied to the distal end of the drive shaft. When an obstruction at the distal end is detected, by a drop in the motor rotational speed, the motor is released and is allowed to spin freely as a flywheel. The freely-spinning motor allows the large angular momentum of the system to dissipate rapidly and safely, without excessive torque to the drive shaft.

The invention provides a rotational atherectomy system, device and method comprising a flexible, elongated, rotatable drive shaft with an abrasive section within a pre-curved section of the drive shaft. The device may further comprise a concentric or eccentric enlarged diameter section that is at least partially covered with abrasive material to comprise the abrasive section. The abrasive section may further comprise an abrasive crown or burr mounted to the drive shaft. The pre-curved drive shaft allows smaller diameter and / or massive abrasive regions to be used while sweeping larger diameters during high-speed rotation. The pre-curved region is substantially straightened for insertion into vasculature and placement adjacent stenosis by insertion of the guide wire. Removal of guide wire proximally from the pre-curved region allows the drive shaft to return to its pre-curved form for ablation. Reinsertion of the guide wire beyond the pre-curved region straightens the drive shaft for ease of removal.

The invention provides a rotational atherectomy device having, in various embodiments, a flexible, elongated, rotatable drive shaft with a system of eccentric abrading heads attached thereto. At least part of the eccentric enlarged abrading heads in the system have a tissue removing surface—the abrading heads may be at least partially hollow. Preferably the abrading heads have centers of mass spaced radially from the rotational axis of the drive shaft, facilitating the ability of the system of abrading heads to work together to open the stenotic lesion to a diameter larger than the outer resting diameter of the abrading heads when operated at high speeds. Therefore, certain embodiments comprise a system having unbalanced centers of mass to not only stimulate greater rotational diameters but also arranged in a manner whereby a debris-removing augering effect occurs. Other embodiments may comprise systems having abrading heads with balanced centers of mass.

The invention provides a rotational atherectomy device having a flexible, elongated, rotatable drive shaft with an abrasive section comprising an enlarged diameter section of the drive shaft or, alternatively, a solid abrasive crown which may be attached to the drive shaft. The device further comprises a proximal and / or a distal counterweight attached to the drive shaft, spaced from the abrasive section wherein each counterweight has its center of mass offset from the longitudinal axis of the drive shaft to stimulate orbital motion by the abrasive section. When placed within an artery against stenotic tissue and rotated at sufficiently high speeds (e.g., in the range of about 20,000 rpm to about 200,000 rpm) the orbiting nature of the abrasive section causes such section to rotate as to open the stenotic lesion to a diameter substantially larger than the resting outer diameter of the abrasive section.

An rotational atherectomy apparatus for abrading tissue, comprising: a flexible, elongated, rotatable drive shaft having a proximal end and a distal end opposite the proximal end; a nose cone operatively attached proximate the distal end of the drive shaft comprising a distal tapered section and a plurality of elongate, flexible members adjacent to the distal tapered section of the drive shaft, each member in the plurality being fixed at both a proximal end and a distal end opposite the proximal end; a proximal mount rotatable with the drive shaft and fixedly connected to the proximal ends of all the flexible members in the plurality; and a distal mount axially separated from the proximal mount and fixedly connected to the distal ends of all the flexible members in the plurality. When the axial separation of the proximal and distal mounts is reduced by pulling the distal tapered section proximally, each member in the plurality bows outward from the drive shaft and expands radially in an at least partially elliptical profile.

A rotational atherectomy device for removing a stenotic tissue from a vessel of a patient is disclosed. The device comprises a rotatable, flexible, hollow drive shaft having an open distal end. The drive shaft comprising a fluid impermeable wall, an abrasive element mounted to the drive shaft proximal to and spaced away from its distal end, the fluid impermeable wall being formed from a torque transmitting coil and at least one fluid impermeable membrane which define a lumen for the antegrade flow of pressurized fluid through the drive shaft and into a distal fluid inflatable support element to inflate said fluid inflatable support element. The distal fluid inflatable support element is located at the distal end of the drive shaft and has an outer wall comprising an outflow opening located such that said outflow opening faces an inner surface of a treated vessel during rotation of the drive shaft so that a flow of fluid out of said opening forms a layer of fluid between the outer wall of the fluid inflatable distal support element and a wall of the treated vessel. The layer of fluid forming a fluid bearing between the outer wall of the rotating fluid inflated distal support element and the wall of the treated vessel.

An atherectomy device with an exchangeable drive shaft is disclosed, having a mechanical coupling that can allow for axial translation of the drive shaft while keeping the drive shaft rotationally locked to the prime mover. The coupling is geometrically keyed, with one side of the coupling having an aperture with a particular internal cross-section, and the other side of the coupling having an external cross-section that matches all or a part of the corresponding internal cross-section. Key shapes may be hexagonal, square, n-sided polygonal, star-shaped, or any other suitable shape. The keys may optionally include one or more rounded corners to simplify manufacturing. Axial motion may be locked by an optional twist-lock connection of two elements that surround the keyed coupling.

The invention provides a rotational atherectomy device having, in various embodiments, a flexible, elongated, rotatable drive shaft with at least one asymmetric and at least partially spherical abrading element attached thereto, which comprises an abrasive surface. The abrading element comprises more mass above the drive shaft than below and comprises a flattened side or transverse surface which creates hard cutting edges and spaces the center of mass radially from the rotational axis of the drive shaft. Thus the center of mass is moved vertically and transversely by the structure of the abrading element, conferring geometric and mass eccentricity upon the element. When placed against stenotic tissue and rotated at high speed, the eccentric nature of the abrading element moves along an orbital path, opening the lesion to a diameter larger than the resting diameter of the abrading element.

The invention provides a rotational atherectomy device having, in various embodiments, a flexible, elongated, rotatable drive shaft with at least one flexible or inflexible eccentric enlarged abrading and cutting head attached thereto which comprises an abrasive surface. When placed against stenotic tissue and rotated at high speed, the eccentric nature of the abrading and cutting head moves along an orbital path, opening the lesion to a diameter larger than the resting diameter of the enlarged abrading and cutting head. Preferably the abrading and cutting head has a center of mass spaced radially from the rotational axis of the drive shaft, facilitating the ability of the device to travel along an orbital path. The abrading and cutting head comprises proximal and / or distal radiused surfaces that facilitate cutting difficult stenosis material while minimizing trauma to the vessel.

The invention provides a rotational atherectomy device having, in various embodiments, a flexible, elongated, rotatable drive shaft with at least one flexible or inflexible eccentric enlarged abrading and cutting head attached thereto which comprises an abrasive surface. When placed against stenotic tissue and rotated at high speed, the eccentric nature of the abrading and cutting head moves along an orbital path, opening the lesion to a diameter larger than the resting diameter of the enlarged abrading and cutting head. Preferably the abrading and cutting head has a center of mass spaced radially from the rotational axis of the drive shaft, facilitating the ability of the device to travel along an orbital path. The abrading and cutting head comprises proximal and / or distal radiused surfaces that facilitate cutting difficult stenosis material while minimizing trauma to the vessel. In some cases, the abrading and cutting head is made from a relatively dense metal.

A rotational atherectomy device for removing a stenotic tissue from a vessel of a patient is disclosed. The device comprises a rotatable, flexible, hollow drive shaft having a fluid impermeable wall defining a fluid impermeable lumen of the drive shaft and, an abrasive element mounted to a distal end portion of the drive shaft proximal to and spaced away from a distal support element formed at a distal end of the drive shaft, the distal support element being inflatable by pressurized fluid which flows in an antegrade direction through said lumen of the drive shaft and is at least partially re-directed into the distal fluid inflatable support element. The distal fluid inflatable support element has an outer wall comprising an outflow opening located such that said outflow opening faces an inner surface of a treated vessel during rotation of the drive shaft so that a flow of fluid through said outflow opening forms a layer of fluid between the outer wall of the rotating fluid inflated distal support element and a wall of the treated vessel to form a fluid bearing between the outer wall of the rotating fluid inflated distal support element and the wall of the treated vessel, the drive shaft being comprised of at least one fluid impermeable membrane and at least two torque transmitting coils, one of said coils extending distally beyond the distal end of the other coil and conveying torque to the abrasive element mounted to the drive shaft distal to and spaced away from a portion of the drive shaft formed from the fluid impermeable membrane and said torque transmitting coils.

A rotational atherectomy device for abrading a stenotic lesion from a vessel of a patient comprises a flexible drive shaft (1) which extends towards a distal end of the device, a distal fluid inflatable support element (3, 3″) located at a distal end of the drive shaft and an abrasive element (5) mounted to the drive shaft proximal to and spaced away from the distal fluid inflatable support element. Both the abrasive element and the distal fluid inflatable support element are rotatable together with the drive shaft and the drive shaft comprises a torque transmitting coil (2) which defines a long lumen of the drive shaft. The distal fluid inflatable support element is formed from a fluid impermeable membrane (9, 9″) that crosses a longitudinal axis (x-x) common to the torque transmitting coil and the lumen of the drive shaft at the distal end of the device, thereby preventing pressurized fluid flowing along the lumen of the drive shaft from entering the vessel in the direction of said longitudinal axis so that fluid has to pass through the fluid inflatable support element, inflating said support element and exiting from the device through an outflow opening (66) in the fluid inflatable support element in a direction different from the direction of the longitudinal axis of the coil and the lumen.

The invention provides a rotational atherectomy system, device and method comprising a bi-directional drive shaft with a flexible ablation element disposed at the distal end of the drive shaft. The flexible ablation element comprises a first retracted position for insertion into vasculature and a second expanded position for ablation, i.e., cutting, sanding and / or grinding. The ablation element comprises more than one flexible finger or blade which allows changing, in certain embodiments, of curvature radius to fit inside a deployment catheter and / or enlarge to the diameter of larger lumens, up to at least 9 mm in diameter. Bi-directional rotation of the expanded ablation element allows cutting in one rotational direction and grinding and / or sanding in the opposite rotational direction.