The relationship between growth of atherosclerotic plaques, variant angina and sudden death.

Clinico-pathological findings are described in two patients with typical variant angina who died suddenly during an ischemic attack. In both cases, detailed pathologic examination of the coronary arteries disclosed severe focal atherosclerosis of the anterior descending coronary artery. The only distinctive histological finding was new intimal proliferation of smooth muscle cells enmeshed within mucoid substance, superimposed on the old fibrous cap of the plaque. These findings agree with experimental and clinical data which suggest that coronary vasospasm may be related to growth of atherosclerotic plaques. This study provides histological evidence that progression of an atherosclerotic plaque may underlie variant angina and sudden death.