We report a 42-year-old female who presented with retrosternal pain, dyspnoea and nausea. Electrocardiography suggested a recent anterior myocardial infarction. However, emergency coronary angiography showed normal blood flow through all the coronary arteries. Paroxysmal hypertension raised the suspicion of a pheochromocytoma. Indeed, abdominal ultrasonography and computed tomography revealed a mass in the left adrenal gland. Elevated levels of plasma and urine catecholamines supported the diagnosis of pheochromocytoma. Left adrenalectomy was performed without complications and pathological examination revealed a 5.5 cm pheochromocytoma. After surgery, all antihypertensive medication was discontinued and the blood pressure returned to normal within several days. Currently, the patient is asymptomatic, has normal catecholamine levels and the electrocardiographic signs of ischaemia have resolved entirely. This case illustrates that a rare clinical entity such as pheochromocytoma should be considered in the differential diagnosis of acute coronary syndrome.