Cardiovascular Systems, Inc.

Charles A Plowe

Jody Lee Rivers

Cassandra Ann Piippo Svendsen

Scott M Hanson

Walter John Dobrovolny

Michael John Eng

Jesse Darley

Matthew D Cambronne

Cassandra A Piippo

Todd James Bakken

Ryan D Welty

Robert Edward Kohler

David C Franchino

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.

Rotational atherectomy device with electric motor

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.

Bidirectional expandable head for rotational atherectomy device

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.

Directional rotational atherectomy device with offset spinning abrasive 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. In some cases, the abrading and cutting head is made from a relatively dense metal.

Eccentric abrading and cutting head for high-speed rotational atherectomy devices

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Hugo, MN, United States of America

Charles A Plowe