Septal myectomy complicated by an embolic stroke in a patient with hypertrophic cardiomyopathy: a case report

BACKGROUND: Hypertrophic cardiomyopathy is estimated to affect 1 out of every 500 adults in the USA. One of its main complications is left ventricular outflow obstruction, which may require surgical septal myectomy in severe cases. We report a rare complication of postoperative septal akinesis leading to thrombus formation presenting as an acute ischaemic stroke. CASE SUMMARY: A 48-year-old woman presented with acute stroke 2 years after surgical septal myectomy for hypertrophic obstructive cardiomyopathy. Diagnostic workup identified an intraventricular thrombus arising in the left ventricular outflow tract (LVOT). After comprehensive evaluation, it was determined that the thrombus development was a complication of the prior septal myectomy causing focal septal akinesis. Treatment with anticoagulation resulted in improvement of neurological symptoms and resolution of the intraventricular thrombus. DISCUSSION: This case illustrates the rarity and unusual presentation of an intracardiac thrombus that arises from septal myectomy site. A thrombus arising in the LVOT, which is characterized by high gradient laminar flow, is highly unusual. This suggests microscopic and macroscopic alteration in the ventricular septal wall structure, as evident by the septal wall akinesis seen on echocardiography. Recognition of this complication is critical to the selection of appropriate anticoagulation as secondary stroke prevention in these patients.