Current status of atherectomy for peripheral arterial occlusive disease.

Abstract

Atherectomy physically removes plaque by cutting, pulverizing, or shaving it in atherosclerotic arteries using a mechanical, catheter-deliverable endarterectomy device. Theoretically, atherectomy offers the following advantages over percutaneous transluminal angioplasty (PTA): It shows a greater immediate success rate with less dissection and acute occlusion, treats complex lesions, and reduces the restenosis rate. This article presents the unique features of four atherectomy devices designed to meet the above challenges: Simpson AtheroCath, Transluminal Extraction Catheter (TEC), Trac-Wright Catheter, and Auth Rotablator. The results, complications, and limitations reported by clinical investigators are discussed critically and realistically. A new device, the OmniCath, under investigative trial, is presented briefly. Clinical studies evaluating the Simpson AtheroCath have reported impressively high initial success rates (ranging from 82% to 100%) but disparate intermediate patency results (ranging from 35% to 84%). Complications associated with the device include hematoma, pseudoaneurysm, and distal embolization. Clinical studies show that the device is relatively ineffective for treating diffusely diseased and long-occluded lesions. Restenosis has also been a primary constraint of the Simpson device, with reported restenosis rates ranging from 11% to 55% at 6 months. The initial technical and clinical success rates reported with the TEC atherectomy device have been promising at 79% to 92%; however, short- and mid-term follow-up results have been either lacking or disappointing, with a reported patency of 67% at 6 months and 51% at 12 months. Furthermore, the problems of restenosis and reocclusion have limited its short-term benefits. The Trac-Wright catheter has demonstrated widely disparate technical success rates (from 58% to 100%) and clinical success rates (from 33% to 80%). Patency rates reported have been suboptimal, ranging from 25% to 68% at 6 months and 25% to 45% at 12 months. Furthermore, severe complications associated with the device include perforation, dissection, and embolization. Reocclusion also limits the applicability of the device. The reported immediate success rates of 72% to 94% using the Auth Rotablator are similar to those reported for other atherectomy devices. Patencies reported at 1 and 2 years are dismal, ranging from 31% to 61% and from 12% to 18%, respectively. Significant complications are associated with the device, including thrombosis, arterial spasm, hemoglobinuria, hematoma, and embolization. Contrary to previous studies and expectations, perforations and dissections have been encountered by some investigators. Late restenosis and reocclusion are also significant limiting factors of the Auth Rotablator. Atherectomy currently has limited applications for treatment of peripheral arterial occlusive disease. The intermediate- and long-term results obtained with the atherectomy devices are worse than those reported for PTA. Furthermore, all of the atherectomy devices have failed to reduce the restenosis and reocclusion rates from those reported for PTA. The problem of restenosis, reocclusion, and other complications must be solved before atherectomy can be used generally as an alternative to vascular reconstruction procedures such as PTA.