Myocardial injury in patients with aortic stenosis

Clinical studies of patients with aortic stenosis suggest that left ventricular myocardial injury is frequent. To examine the morphologic basis of this observation, we studied 32 patients with isolated aortic stenosis, no cardiac surgery, and hearts studied at autopsy after postmortem arteriography and fixation in distension. The patients were 46-87 years old (average 69), and 21 (66%) were male. Calcific aortic stenosis was present in 19 hearts, 12 had congenital bicuspid aortic valve, and 1 had rheumatic aortic stenosis. In 19 hearts there was moderate or marked coronary atherosclerosis, and 12 hearts had 17 myocardial infarcts. However, among 13 hearts with no or mild coronary atherosclerosis, 9 had either subendocardial myocardial contraction band necrosis, a lesion occurring when periods of no perfusion are followed by reflow, or focal replacement fibrosis. In 13 hearts there was subendocardial vacuolization of myocytes, an alteration produced by ischemia, that was not accounted for by coronary artery disease. Our results are consistent with clinical observations and show that ischemic myocardial injury may be associated with isolated aortic stenosis in the absence of coronary artery obstruction. The contraction band necrosis and vacuolated myocytes suggest that both episodic and sustained reductions of subendocardial blood flow occur in the presence of aortic stenosis.