Spasm in ectatic coronary arteries.

Patients with ectatic coronary arteries often have occlusion of the affected arteries. Because ectatic arteries are considered to have medial damage, they are normally assumed to have little capacity to constrict; therefore, spasm has not been considered a factor in the occlusive process. In two patients who had diffuse coronary ectasia, no appreciable stenosis, and angina pectoris, we found that the ectatic arteries indeed had an augmented vasoconstrictor response to ergonovine. This finding indicates that some ectatic arteries have a sufficient amount of smooth muscle to cause coronary spasm and may produce symptoms of coronary disease by causing recurrent arterial spasm.