Ruptured pheochromocytoma presenting with acute myocardial injury and hemoperitoneum.

Pheochromocytoma is an uncommon neuroendocrine tumor that may present with highly variable and misleading clinical manifestations. We report the case of a 64-year-old woman with a history of hypertension who presented with acute chest pain, electrocardiographic changes, and marked elevation of cardiac biomarkers, initially suggestive of an acute coronary syndrome. Coronary angiography revealed no obstructive coronary disease. During hospitalization, the patient developed severe hemodynamic instability with alternating hypertensive crises and hypotension. Imaging studies identified a large heterogeneous right adrenal mass with high attenuation and associated hemoperitoneum. Biochemical evaluation demonstrated markedly elevated urinary metanephrines and normetanephrines, confirming the diagnosis of pheochromocytoma. The patient was stabilized medically and treated with preoperative α-adrenergic blockade using doxazosin, followed by successful surgical resection. Histopathological examination revealed extensive tumor necrosis with minimal viable tissue. Postoperatively, the patient had an uneventful recovery, with normalization of blood pressure and no recurrence of symptoms during follow-up. This case highlights the diagnostic and therapeutic challenges posed by pheochromocytoma presenting as acute myocardial injury and complicated by spontaneous tumor rupture with hemoperitoneum.