Perioperative Management of a Patient with Hypertrophic Obstructive Cardiomyopathy.

Abstract

A 69 year old female with medical history of HOCM, GERD, HTN, A-fib with RVR, NSTEMI, and CVA, presented for an EGD. She had undergone a cardiac myomectomy for HOCM one year prior, with transthoracic echocardiogram showing immediately prior to myomectomy demonstrating an LVOT gradient of 80 mmHg at rest and 178 mmHg with the Valsalva maneuver. She developed an acute gastrointestinal bleed secondary to ulcers, resulting in a hemoglobin drop from 12.3 to 7.8 g/dL and persistent tachycardia in the 120s despite transfusion with one unit of packed red blood cells. Her home metoprolol had been held due to concerns about hypotension. Prior to the procedure, metoprolol was administered along with a second unit of PRBCs. Intraoperatively, a phenylephrine infusion was utilized alongside a small dose of fentanyl, oral lidocaine, and a propofol infusion. The patient was successfully weaned off phenylephrine in the PACU and tolerated the endoscopic procedure without complications. HOCM is a genetic cardiac disorder recognized as the leading cause of sudden cardiac death in young people. At least 1400 genetic markers have been associated with this condition, making it incredibly heterogeneous. With this heterogeneity, many cases go unrecognized and are asymptomatic for their entire lives. This means that patients may present at any age without a prior diagnosis of this condition. When symptomatic, its pathophysiology is characterized by hyperdynamic left ventricular function, which can generate a Venturi effect that draws the anterior mitral valve leaflet into the LVOT, sealing against the hypertrophied septum and causing dynamic obstruction at the base of the aorta. Effective anesthetic management, therefore, relies on five key principles: increasing preload, increasing afterload, reducing heart rate, decreasing contractility, and maintaining sinus rhythm. Optimizing preload and afterload prevents LVOT collapse and is achieved through fluid resuscitation and the use of peripherally selective vasopressors like phenylephrine. Heart rate and contractility are controlled with negative inotropes, typically β1-selective β-blockers. Antiarrhythmics such as amiodarone should be considered if necessary for arrhythmia management. With meticulous preoperative planning and hemodynamic optimization, anesthesia providers can significantly improve outcomes for patients with HOCM.