Transluminal coronary angioplasty of postmortem human hearts.

Twelve autopsy human hearts were submitted to coronary angiography and coronary arterial balloon angioplasty. The effect of angioplasty was determined by follow-up coronary angiography as well as gross and microscopy inspection of the coronary arteries dilated. Fifty-four dilations were performed in 24 coronary arteries. Angiographically 50 of the 54 dilations resulted in a mean (+/- standard deviation) increase in luminal diameter ranging from 1.9 +/- 0.9 to 2.7 +/- 0.8 mm. Failure to increase luminal size was usually related to a predilation coronary diameter greater than that of the inflated angioplasty balloon. Dilation resulted in mural disruption with intimal or medial tears, or both, in 65 percent of arteries dilated. Disruption was more frequent in arteries with atherosclerosis and calcification. The mechanism of luminal enlargement in coronary angioplasty may be focal damage to the arterial wall with intimal or medial splitting as opposed to plaque compression as initially suggested.