USEFULNESS OF A PROTOTYPE DIRECTIONAL CATHETER FOR EXCIMER-LASER CORONARY ANGIOPLASTY IN NARROWINGS UNFAVORABLE FOR CONVENTIONAL EXCIMER OR BALLOON ANGIOPLASTY

We report clinical and angiographic results in 53 patients with 57 significant coronary or saphenous vein graft narrowings treated with directional excimer laser angioplasty. The target vessels were the left main (1%), anterior descending (32%), circumflex (19%), right coronary artery (39%), and vein grafts (9%). Lesions were morphologic class Pr (18%), B2 (79%), or C (3%), with 40 de novo and 17 restenotic lesions, Adjunctive balloon angioplasty was used in 53 lesions (93%), Mean pre- and postprocedural minimal lumen diameters were 0.6 +/- 0.3 and 1.9 +/- 0.7 mm (p<0.001), corresponding to a mean diameter stenosis of 72 +/- 20% and 27 +/- 16%, Procedural success rate was 91%. Cumulative risk of death, Q-wave myocardial infarction, or emergency bypass operation was 9% (5 patients), Of patients who had a successful laser procedure, 28 (60%) with 30 lesions underwent angiographic follow-vp at 6 +/- 3 months after the procedure, Restenosis rates (>50% diameter restenosis or acute gain loss) were 37% and 23%, respectively Four patients underwent bypass, 3 angioplasty, and; patient died from cancer. This study demonstrates the feasibility of directional application of laser energy to selected unfavorable narrowings for conventional excimer laser or balloon angioplasty, Further evaluation of this device using the now standard saline infusion technique is necessary to establish its ultimate role as a primary interventional device.