FRI194 Pheochromocytoma Presenting As Catecholamine-Induced Cardiomyopathy: A Case Report

Disclosure: M. Tsikala Vafea: None. D. Lee: None. Introduction: Pheochromocytoma (PCC) is a rare catecholamine-secreting neuroendocrine tumor presenting with the classic triad of episodic headache, sweating and tachycardia. Catecholamine-induced cardiomyopathy (CICMP) can occur as a complication of PCC in 7-11% of patients. It presents more commonly as dilated cardiomyopathy and inverted Takotsubo cardiomyopathy but also as hypertrophic or unspecified cardiomyopathy. Following appropriate pharmacologic treatment and resection of PCC, these cardiac complications usually resolve. Case report: 36 year old man with history of hypertension presented to the hospital with worsening orthopnea and cough. Following antibiotic treatment failure for suspected pneumonia, he was re-admitted with hemoptysis, tachycardia, hypoxia, and hypertensive emergency. Troponin and brain natriuretic peptide were found to be elevated. CT chest and abdomen showed pulmonary nodules and a large left adrenal mass measuring 9.6x9.3x9.4 cm, concerning for metastatic PCC. He was subsequently started on doxazosin. Transthoracic echo showed bi-atrial enlargement, diffuse severe left ventricle hypokinesis, reduced ejection fraction 25% and diastolic dysfunction. Stress cardiac MRI showed non-ischemic cardiomyopathy, corroborating the diagnosis of CICMP. After achieving adequate alpha-adrenergic blockade, he was started on goal-direct medical therapy consisting of valsartan, metoprolol and empagliflozin. His pulmonary nodular opacities improved on repeat imaging, congruent with pulmonary edema rather than metastases. Plasma and 24-hour urine metanephrines (2,964 pg/mL and 23,310 mcg/24 hr, respectively) and normetanephrines (9,266 pg/mL and 33,927 mcg/24 hr, respectively), as well as dopamine (493 pg/mL), epinephrine (3,205 pg/mL) and norepinephrine (above reportable range of 4,800 pg/mL) eventually came back significantly elevated, confirming his diagnosis of PCC. A month after presentation, he underwent left adrenalectomy, which revealed an 11 cm composite PCC ganglioneuroma. One-month postoperatively, urine metanephrines and normetanephrines were normal but his ejection fraction remained unchanged. Discussion: CICMP should be considered in patients presenting with acute heart failure and an incidental adrenal mass to avoid delays in treatment. Acute pulmonary edema may resemble pulmonary nodules on CT, so interpretation of these findings should correlate with the clinical presentation. Timely initiation of alpha-adrenergic blockade upon suspicion of PCC is crucial as it can significantly improve hemodynamics, and biochemical markers take time to result. 96% of CICMP cases improve after resection of PCC within a variable time frame ranging from one week to several months. Our patient’s CICMP had not improved one month after his adrenalectomy, but it remains to be seen whether he eventually recovers his cardiac function. Presentation: Friday, June 16, 2023