Pheochromocytoma presenting as severe biventricular failure requiring insertion of a biventricular assist device.

ATASTROPHIC CARDIOMYOPATHY resulting from pathologic catecholamine release has been well described in several disease states. Pheochromocytoma, a rare neuroendocrine tumor, can present with acute and profound myocardial depression requiring inotropic support and, in some instances, left ventricular assist device insertion. An unusual case of occult pheochromocytoma presenting as diabetic ketoacidosis (DKA) and biventricular failure, which was then managed with insertion of a biventricular assist device (BiVAD) and, subsequently, surgical resection of the primary tumor is presented. CASE REPORT The patient was a 38-year-old man with a past medical history significant for type-1 diabetes and mild mental retardation with developmental delay. He presented to an outside hospital with nausea, vomiting, fever, and signs of DKA. The laboratory workup revealed an initial blood glucose level of 1,100 mg/dL, arterial pH of 6.9, and an anion gap metabolic acidosis. After admission, he was intubated for acute respiratory failure. Upon transfer to The Mount Sinai Hospital, an echocardiogram revealed severely depressed left ventricular function (ejection fraction 5%-10%) with global hypokinesis and mild tricuspid and mitral regurgitation. An attempt was made to place a tandem heart percutaneous ventricular assist device without success. Despite intense inotropic and vasopressor support, the patient’s condition continued to deteriorate with the development of acute renal failure and mild hepatic failure. The cardiothoracic surgery service was consulted and a Thoratec CentriMag (Thoratec Corp, Pleasanton, CA) was implanted. Over a short span of 4 days, inotropes were weaned, and the BiVAD was explanted. A transthoracic echocardiogram revealed normalization of right and left ventricular function. Despite this, the patient was unable to be weaned from the ventilator secondary to an ongoing systemic inflammatory response syndrome and the development of pneumonia. Because of prolonged endotracheal intubation, a tracheostomy was performed. On postoperative day 5, the patient developed unexplained elevated serum lactate levels with acidosis. Variations in blood pressure also were noted. A computed tomography (CT) scan of the abdomen was performed to exclude possible ischemic bowel. There was an incidental finding of a 6.5-cm left suprarenal mass (Fig 1). Pheochromocytoma was considered in the differential diagnosis of a possible adrenal mass in the setting of labile blood pressure. The patient was treated with large doses of norepinephrine and other vasopressor agents precluding the immediate use of serum catecholamine levels for diagnostic purposes. After successful weaning of all vasopressors, urinary metanephrines levels were found to be markedly elevated at greater than 10,600 nmol/24 hours (normal, 1-145 nmol/24 hours), and plasma metanephrines were noted to be greater than 7,100 pmol/L (normal, 0-62 pmol/L). While awaiting the results of the urinary and plasma metanephrines, a meta-iodobenzylguanidine scan was requested and found to be strongly positive and supportive of the diagnosis of pheochromocytoma. In addition, while this evaluation was being completed, an -receptor blockade with phentolamine was instituted. After 14 days and adequate establishment of the -receptor blockade, an infusion of esmolol was begun. The patient was then taken to the operating room for surgical resection of the presumed pheochromocytoma. Anesthetic management included 1% isoflurane in 80% oxygen/air, fentanyl, and cisatracurium infusion. A pulmonary arterial catheter and transesophageal echocardiography were used to assist with fluid management. The infusions of phentolamine and esmolol were discontinued before ligation of the adrenal vessels (Fig 2). Immediately after ligation, fluid resuscitation and vasopressor therapy were needed to restore blood pressure and perfusion. With continued resuscitation, the patient left the operating room on minimal vasopressors. Her postoperative course was complicated by critical illness polyneuropathy that eventually resolved. The patient was subsequently discharged from the hospital in good condition.