Mechanical dilatation rather than plaque removal as major mechanism of transluminal coronary extraction atherectomy.

Atherectomy with the transluminal extraction endarterectomy catheter (TEC) is a new approach for treatment of coronary artery disease, which continues to undergo FDA investigational studies. The major mechanism of the TEC device should be excision of plaque and its removal due to suction applied through an attached vacuum. We report about the acute results in 24 patients treated with TEC atherectomy in native vessels and the outcome of 18 patients who, until recently, underwent follow-up catheterization after 6 months. The procedure was successful (residual stenosis less than 50%) in 7 of 24 patients with TEC atherectomy alone (29%); 15 of 24 patients (65%) required additional PTCA in order to achieve angiographic success (10 of 24) or to treat total occlusion (2 of 24) or distal embolization (3 of 24) following atherectomy. One TEC attempt failed due to guiding catheter problems, another major complication was a vessel perforation leading to a non-Q wave infarction. The minimal residual diameter after passage of the stenosis (prior to additional PTCA) with the 5.5 Fr catheter (n = 14) was 1.5 +/- 0.2 mm, with the 6 Fr catheter (n = 9) 1.8 +/- 0.4 mm, and 2.2 +/- 0.2 mm using the 7 Fr catheter (n = 10). The histologic findings revealed intimal cells, fibrous tissue, and homogenate with no identifiable tissue in five cases (21%), whereas in 17 patients (72%) light microscopy could only assess blood cells.(ABSTRACT TRUNCATED AT 250 WORDS)