Extra-adrenal pheochromocytoma is rare and presents variable symptoms. Its difficulty to diagnosis delays appropriate treatment. We would like to report an unusual case of extra-adrenal pheochromocytoma. The patient came to the emergency room with dyspnea, palpitation, and cyanosis. He had a history of hospitalization for Fontan operation due to congenital heart disease. Despite medication, his blood pressure remained high. After additional laboratory and image exams, he was diagnosed with extra-adrenal pheochromocytoma and had surgical treatment. The final pathology report was extra-adrenal pheochromocytoma with high risk of malignancy. The postoperative course was uneventful and showed normal laboratory results even after 3 months of outpatient follow-up. Extra-adrenal pheochromocytoma presents variable symptoms. We should consider endocrinologic diseases like extra-adrenal pheochromocytoma in cases presenting with palpitation and high blood pressure, even with a past history of cardiac surgery.
Keywords: Congenital heart defect; Fontan procedure; Paraganglioma; Pheochromocytoma.