Safety of preoperative carvedilol in a patient with recent atenolol-induced pheochromocytoma crisis and cardiomyopathy: A case report

INTRODUCTION: Beta-adrenergic blockade without adequate alpha blockade is an established trigger of pheochromocytoma crisis (PC). Carvedilol is a nonselective beta-adrenergic and alpha 1-adrenergic blocking agent, and its use for preoperative preparation of pheochromocytoma patients with prior cardiomyopathy secondary to PC resulting from unopposed beta-blocker therapy has never been reported. CASE PRESENTATION: A 48-year-old woman was admitted to the Urology Department for evaluation of a huge right upper abdominal mass. She developed hypertensive crisis with acute pulmonary edema resulting in respiratory failure after administration of atenolol to treat hypertension and tachycardia. Transthoracic echocardiogram revealed global hypokinesia. The patient was managed with intravenous nicardipine, furosemide, and prazosin because of the clinical suspicion of pheochromocytoma that was subsequently confirmed by elevated plasma and urine catecholamine levels. Within 3 days of alpha-adrenergic blockers treatment, there was rapid amelioration of hypertension and pulmonary congestion, as well as normalization of left ventricular function by echocardiography. However, tachycardia persisted after 1 month of adequate alpha-adrenergic blockade. Given the benefit of beta-adrenergic blockers in patients with systolic dysfunction, we slowly titrated carvedilol while carefully monitoring the patient's condition in the intensive care unit. Tachycardia was controlled without inducing PC. Surgical resection was successful without perioperative complications. CONCLUSION: Clinicians should be cautious when prescribing beta-adrenergic blocker in patients with hypertension and upper quadrant mass of unknown etiology. The mass may be pheochromocytoma. Preoperative use of carvedilol after sufficient alpha-adrenergic blockade for control of tachycardia in a patient with prior cardiomyopathy associated with atenolol-induced PC is safe and effective.