Transcatheter aortic valve implantation (TAVI) has emerged as a less invasive and potentially high efficacious procedure for the treatment of high-risk patients with symptomatic aortic stenosis. Appropriate patient selection for TAVI is a key component to ultimate clinical success. Herein, we describe a patient with left ventricular outflow tract (LVOT) obstruction that became apparent only following relief of aortic stenosis with TAVI. This report highlights the dynamic nature of LVOT obstruction, which was successfully treated in our patient with catheter-based alcohol septal ablation. The potential to unmask dynamic LVOT obstruction with TAVI should be an important consideration in patient selection for the procedure, and the postoperative assessment of these patients. © 2012 Wiley Periodicals, Inc.