Ablation system with catheter clearing abrasive

摘要

An ablation system is provided that comprises an atherectomy device and an aspiration catheter, each routed to a position just proximal to a lesion within a patient's vessel to ablate and remove the lesion so that blood flow through the vessel is adequately restored. The atherectomy device includes a flexible driveshaft coupled to an ablation burr. The ablation burr includes a concave front surface having an abrasive disposed thereon and a generally frusto-conical rear surface having an abrasive disposed thereon. The aspiration catheter has an elongate body and includes a centrally located lumen that is separated into two portions having different inner geometries. The two portions consist of a generally constant inner diameter portion and a frusto-conical distal portion. The distal portion of the lumen is positioned approximately at the distal end of the catheter to define an aspiration mouth. The distal portion narrows from the distal end of the catheter toward the proximal end of the catheter in an inwardly tapered manner to form generally frusto-conical inner surface. The taper of the inner surface of the catheter generally corresponds to the taper of the rear surface of the ablation burr so that the ablation burr may be pulled back into the distal portion of the lumen of the catheter during operation of the system.