Fibromuscular dysplasia and acute myocardial infarction: evidence for a unique clinical and angiographic pattern.

Fibromuscular dysplasia (FMD) is a noninflammatory, nonatherosclerotic disease of the small- to medium-sized vessels that primarily affects young females in their second to fourth decades of life. Typically, FMD involves the renal and extracranial arteries, but at autopsy, it has also been reported to affect the coronary arteries. However, its association with acute coronary syndromes is not yet well recognized. We describe three cases of FMD that presented with an acute myocardial infarction as the initial manifestation and discuss a specific pattern found in all cases as well as the possible patholophysiologic mechanism responsible for the acute coronary syndrome.