Radiation Following Percutaneous Balloon Aortic Valvuloplasty to Prevent Restenosis

The RADAR trial is a prospective, randomized, double-blind, sham-controlled, two-stage, adaptive clinical trial. Following successful Balloon Aortic Valvuloplasty, patients with severe aortic stenosis will be randomized in a 2:1 fashion to External Beam Radiation Therapy (EBRT) plus standard medical therapy or standard medical therapy along with sham EBRT (placebo). During Stage One, approximately 110 patients will be enrolled in order to have 80 patients randomized and 66 patients with valid 6 month data. The sample size for Stage Two will be calculated at the end of Stage One. At the time of study commencement, the expectation is that the total sample size will be approximately 155 patients with valid 6-month data, and thus 195 will be randomized and up to 250 enrolled. Patients will be followed for a period of two (2) years. Echocardiographic and clinical endpoint data will be collected and analyzed.