Nearly 300,000 people in the U.S. have severe aortic stenosis (AS), a condition in which their aortic valve doesn’t open fully, causing a decreased blood flow from the heart to the body. Patients with aortic stenosis, as well as those not suitable for open heart surgery, may receive a balloon valvuloplasty or a Medtronic CoreValve aortic valve replacement.

During a balloon valvuloplasty, a thin flexible tube, called a catheter, is inserted through the artery to widen the valve opening. The catheter and deflated balloon are then removed from the valve.

AS can also be treated with a Medtronic CoreValve aortic valve replacement, a non-surgical, minimally invasive technique in which a valve made from pig heart tissue is implanted using an artery that leads to the heart. The valve leaflets are secured into a flexible, self-expanding metal frame for support. Patients who are considered high risk or ineligible for aortic valve surgery may be considered for the clinical trial.