Bail-Out Alcohol Septal Ablation for Left Ventricular Outflow Tract Obstruction After Transcatheter Mitral Valve Replacement.

A 76-year-old woman with degenerative mitral valve disease was referred for refractory heart failure. An echocardiogram showed the presence of a massive mitral annular calcification with severe stenosis (mitral valve area, 1.0 cm; mean gradient, 11 mm Hg) and a small left ventricular cavity with a 23-mm septal bulge without obstruction (Figures 1A to 1C, Online Video 1). Computed tomography (CT) findings were almost circumferential calcification of the mitral annulus; mitral annulus diameter of 22.8 30.0 mm and area of 472 mm, and mitral annulus-aorta angle of 122 (Figures 1D to 1F). The heart team recommended a transcatheter mitral valve replacement (TMVR). The procedure was performed via the transseptal approach using a 26-mm SAPIEN 3 valve (Edwards Lifesciences, Irvine, California) (Online Video 2). Immediately after deployment, the patient had severe hypotension requiring hemodynamic support (Figures 2A and 2B). An echocardiographic assessment showed a satisfactory function of the prosthesis (trace paravalvular leak and a mean gradient of 5 mm Hg), which contacted the septum, leading to a severe left ventricular outflow