Laser recanalization of acutely thrombosed coronary arteries in live dogs: early results.

Laser recanalization was attempted in thrombosed coronary arteries of 10 dogs. In all dogs a coronary thrombus was obtained by passing a low grade electrical current through a guide wire advanced into the artery. Recanalization was then attempted using an argon laser with energy levels ranging from 3 to 30 J. In six dogs a 140 micron core optical fiber was positioned proximal to the thrombus and lasing was done during fiber advancement. The thrombosed artery was recanalized in one dog, perforated in four and neither recanalized nor perforated in one. In the remaining four dogs a steerable guide wire was advanced across the thrombus and a catheter was passed over the guide wire and exchanged for a 200 micron core optical fiber. After fiber withdrawal, mechanical recanalization without lasing was performed in one of the four dogs. In the remaining three dogs, both the fiber and the catheter were again advanced distal to the thrombus and lasing was done during withdrawal; this caused coronary perforation in all dogs. Laser recanalization of thrombosed coronary arteries in dogs using currently available techniques is feasible but results in a very high incidence of perforation.