Hemolytic Anemia Caused by Dynamic Left Ventricular Outflow Tract Obstruction Following Surgical Aortic Valve Replacement: A Case Report.

Hemolysis following surgical aortic valve replacement (SAVR) is typically attributed to paravalvular leakage or prosthetic valve dysfunction. However, we present a rare case of hemolytic anemia caused by dynamic left ventricular outflow tract obstruction (LVOTO) due to septal hypertrophy following SAVR with a bioprosthetic valve. A 78-year-old woman underwent SAVR with annular enlargement via the Manougian procedure. Despite an uneventful intraoperative course and initial recovery, she developed progressive hemolysis postoperatively without evidence of valve dysfunction or paravalvular regurgitation. Echocardiography revealed dynamic LVOTO and moderate mitral regurgitation (MR). Conservative treatment, including beta blockers and calcium channel blockers, led to improvement of the obstruction and resolution of hemolysis. This case highlights the need to consider dynamic LVOTO in the differential diagnosis of post-SAVR hemolysis and to more aggressively evaluate the indication for concomitant septal myectomy in patients with preexisting hypertrophy.