Pheochromocytoma and acute myocardial infarction. When a pheochromocytoma is manifested as an acute myocardial illness, diagnosis may be difficult to make. If the tumor is suspected early enough, a workup can be done while the complications of the myocardial illness are being controlled (as in our case). The tumor can then be expeditiously removed before any further problems develop. The case presented here underscores the importance of maintaining a high index of suspicion for a pheochromocytoma in any patient who has an unexpected myocardial event. 