This report describes the occurrence of a pheochromocytoma in a middle-aged, black female with a 12-year history of hypertension, and a strong family history of hypertension. In this case, the pheochromocytoma was associated with a subendocardial myocardial infarction and congestive heart failure which occurred in the presence of large, dilated coronary arteries without intraluminal obstructions. The patient also had the murmur and echocardiographic and ventriculographic signs typical of idiopathic hypertrophic subaortic stenosis, which resolved following removal of the tumor and return of the blood pressure to normal. The authors believe this to represent a form of transient physiological hypertrophic subaortic stenosis secondary to a hypercatecholamine state.