Coronary histology after percutaneous transluminal coronary angioplasty.

This article describes previously unreported histologic changes in the vessels of a patient who was admitted with an evolving myocardial infarction due to subtotal occlusion of the left anterior descending coronary artery. The patient died of cardiogenic shock 15 hours after undergoing a technically successful percutaneous transluminal coronary angioplasty procedure. Upon early postmortem study, histologic sections from the proximal, middle, and distal thirds of the left anterior descending coronary artery were polymorphic in appearance. Sections from the most proximal angioplasty site revealed intimal proliferation of polymorphonuclear leukocytes, as well as intimal fibrosis with plaque cleavage. Sections from the more distal angioplasty sites revealed plaque cleavage, intimal polymorphonuclear infiltration, and intimal, medial, and adventitial fracture with dissecting hemorrhage, although mural integrity had been maintained. Intense subintimal proliferation with inflammatory cells has previously been described only in an experimental animal model. Our case also appears to be the first in which adventitial disruption has been observed after percutaneous transluminal coronary angioplasty; this finding provides new evidence that an atherosclerotic coronary artery can tolerate vigorous dilatation without rupture.