A case of paroxysmal pheochromocytoma concurrent with coronary artery aneurysm presenting as acute coronary syndrome

A 51-year-old man recently diagnosed with preclinical Cushing's syndrome complained of chest oppression concomitant with back pain. Following contrast-enhanced computed tomography (CT) to rule out acute aortic dissection, he developed chest symptoms accompanied by elevation of blood pressure to 240/120 mmHg and ischemic electrocardiographic change. Urgent coronary angiography revealed a coronary artery aneurysm (15 mm × 6 mm) in the distal portion of the left anterior descending artery concomitant with coronary flow delay. Re-analysis of the blood sample taken at admission showed elevated plasma catecholamine concentrations, leading to a diagnosis of paroxysmal pheochromocytoma. An adrenal tumor was excised laparoscopically and histologically shown to be a pheochromocytoma. These findings show that coronary artery aneurysm may be a rare complication of pheochromocytoma, and indicate that monitoring of blood pressure or analysis of stored blood samples, if necessary, is essential to detect pheochromocytoma when using contrast medium or glucagon in patients known to have an adrenal incidentaloma. It should be noted that pre-treatment with an α-blocker is necessary when patients who are likely to have pheochromocytoma need to undergo contrast-enhanced CT.