I t has been reported that when the diagnosis of a pheochromocytoma is not made before anesthesia and surgery, hypertensive and/or hypotensive crisis may occur, possibly resulting in unexpected circulatgry shock or sudden death) '2 It is, therefore, essential to be alert for the possible existence of the disease, and to make a strong recommendation for routine preoperative screening for a pheochromocytoma in any recently diagnosed hypertensive patient. 3 However, many drugs, vitamins, and foodstuffs interfere with the analysis of urinary catecholamines an~t vanillylmandelic acid (VMA). 4 Thus, the Ser-Ap-Es (combination tablet of reserpine 0.1 mg, hydralazine hydrochloride 25 mg, and hydrochlorothiazide 15 mg). She also had type II diabetes mellitus, which was treated with 40 units of NPH insulin daily. Two months before entering the hospital for surgery, she was hospitalized following a prolonged episode of chest pain. However, no laboratory findings suggested an acute myocardial infarction. One month prior to the present admission, she was reevaluated for her symptoms, which consisted of chest pain, dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea, and pedal edema. During a physical examination she experienced another episode of chest pain with ischemic changes on the electrocardiogram (ECG). Five days prior to the present admission, she was admitted to the Coronary Care Unit for follow-up. She was scheduled for cardiac catheterization since diagnosis of a pheochromocytoma is still considthere were no demonstrable changes in either serial ECGs or ered one of many challenging problems in clini! .'. efizyme studies. Her arterial blood pressure was usually in cal medicine) Hypertension is the clinical hall, . t he range of 130/70 mmHg, except for a few mild hypertenmark of a pheochromocytoma, but it is no t sive episodes (>160/80 mmHg), which were not related to always present. Headache, palpitations, and diaphoresis are common manifestations, but in rare cases the tumor may cause neither signs nor clinical symptoms. 6 The following case report illustrates the grave complications of an undiagnosed pheochromocytoma in a woman who was essentially asymptomatie until she underwent coronary artery bypass graft (CABG) surgery. She died of acute heart failure resulting from "malignant" hypertension and tachycardia during the perioperative period.
