MON-472 Two Cases of Pheochromocytoma Presenting as Acute Heart Failure and Cardiogenic Shock During Pregnancy

Abstract V. Cascio: None. F. Benyaminov: None. A. Wang: None. A. Sinha: None. Two Cases of Pheochromocytoma Presenting as Acute Heart Failure and Cardiogenic Shock During Pregnancy Background: Previously undiagnosed pheochromocytoma may be unmasked during pregnancy due to physiologic stress, compression of the tumor by the gravid uterus, and/or gestational hormones precipitating marked catecholamine release. “Pheochromocytoma crisis” can manifest with severe blood pressure variability and organ failure including acute heart failure causing cardiogenic shock. We present two cases of pregnant patients with pheochromocytoma. Clinical cases: The first case is a 25-year-old woman, 18 weeks pregnant, presenting with nausea, vomiting, and SOB. She briefly lost her pulse and underwent CPR before achieving ROSC. She was intubated and started on ECMO for cardiogenic shock and extremely labile BP. She underwent urgent atrial septostomy for LV venting. Echocardiogram demonstrated EF <20%. CT scan demonstrated a 12.0 x 9.9 x 10.7 cm right adrenal mass. Laboratory evaluation including plasma metanephrine (1188 pg/mL, n<88 pg/mL) and normetanephrine (5118 pg/mL, n<210 pg/mL) was diagnostic of pheochromocytoma. The patient was treated with phenoxybenzamine, metoprolol, and sodium chloride tablets, and underwent open right adrenalectomy once stabilized. Pathology confirmed moderately differentiated pheochromocytoma. Repeat echocardiogram and cardiac MRI demonstrated significant recovery of cardiac function. Unfortunately, fetal demise was diagnosed early in the hospital course. Genetic workup revealed a pathogenic mutation in RET consistent with MEN2A. The second case is a 32-year-old woman, 10 weeks pregnant, presenting with nausea, vomiting, and fatigue. She was intubated and required ionotropic support for cardiogenic shock. Echocardiogram demonstrated EF 15-20%. MRI of the abdomen demonstrated a 12.9 x 10.8 x 9.3 cm right adrenal mass. Laboratory evaluation including plasma metanephrine (7472 pg/mL, n<88 pg/mL) and normetanephrine (85904 pg/mL, n<210 pg/mL) was diagnostic of pheochromocytoma. The patient was treated with phenoxybenzamine, IV phentolamine PRN, and carvedilol, and underwent open right adrenalectomy once stabilized. Pathology confirmed poorly differentiated pheochromocytoma. Repeat echocardiogram demonstrated normalization of cardiac function. Patient had a normal fetal US prior to discharge. Conclusion: Pregnant patients with previously undiagnosed pheochromocytoma may present with pheochromocytoma crisis. ECMO and alpha blockade can be used successfully to treat refractory catecholamine-induced cardiogenic shock with recovery of cardiac function. Monday, June 3, 2024