A 68-year-old woman with concentric left ventricular hypertrophy, prosthetic valve endocarditis with aortic root abscess, and sepsis had aortic root replacement with an aortic allograft. On weaning from cardiopulmonary bypass, she had hemodynamic instability caused by systolic anterior motion of the mitral valve, which resulted in a left ventricular outflow tract obstruction; the peak pressure gradient across the left ventricular outflow tract was 130 mm Hg, and there was moderately severe (3+) mitral regurgitation. After reinstitution of cardiopulmonary bypass, a central Alfieri edge-to-edge stitch was placed between the anterior and posterior leaflets of the mitral valve. This reduced the gradient across the left ventricular outflow tract to 10 mm Hg and eliminated the mitral regurgitation, which enabled successful separation from cardiopulmonary bypass.