Transluminal laser irradiation of coronary arteries in live dogs: an angiographic and morphologic study of acute effects.

In vivo coronary transluminal laser irradiation, using energies known to vaporize atherosclerotic plaques and thrombi, was performed in normal coronary arteries of 5 anesthetized mongrel dogs. A 200-mu core silica optical fiber with a radiopaque tip was advanced through a catheter to either the left anterior descending or circumflex coronary arteries. Coronary artery perforation occurred during manipulation of the fiber in 1 dog. In 4 dogs, argon laser radiation was delivered at 1-second intervals. A total of 45 different sites were irradiated in 8 coronary arteries. In 5 of these arteries 1 W was used and in the 3 other arteries 2 W were used. Coronary angiography showed perforation of 5 of these 8 arteries. Two arteries were perforated using 1 W and 3 using 2 W. Within 30 minutes, 3 dogs with perforation died of cardiac tamponade. In all 4 dogs postmortem examination showed perivascular blood extravasation around all 8 lased coronary arteries. Transluminal lasing of normal dog coronary arteries using delivery systems and energies similar to those known to vaporize atherosclerotic plaques and thrombi resulted in arterial perforation, frequently followed by cardiac tamponade.