Vasopressin role in hypertrophic obstructive cardiomyopathy post-cardiac surgery: A case report

Managing left ventricular outflow tract obstruction (LVOTO) and systolic anterior motion (SAM) of the mitral valve can be challenging, especially in the context of circulatory shock and pulmonary edema post cardiac surgery.

We describe a case of an 80-year-old female patient with a history of severe aortic stenosis and hypertrophic obstructive cardiomyopathy that underwent aortic valve replacement and myectomy. The patient presented with acute pulmonary edema and low blood pressure due to LVOTO and SAM post cardiac surgery in the intensive care unit. She was paced with an epicardial dual-chamber pacing system due to complete atrioventricular block and treated initially with norepinephrine, furosemide, and esmolol infusion and continuous positive pressure ventilation. The patient remained hypoxemic and kept deteriorating hemodynamically despite titrating up norepinephrine. The addition of vasopressin infusion and tapering of norepinephrine finally stabilized the patient with significant reduction of LVOTO, confirmed by transthoracic echocardiography assessment, improved oxygenation and increased urine output.

Vasopressin seems to be the preferred vasopressor for managing LVOTO and SAM post-cardiac surgery, because of its absence of inotropic effects. Echocardiography is crucial for early diagnosis and therapeutic management.