What if a heart valve could be replaced without surgically opening the chest cavity?
The leaflets of a calcified aortic valve are unable to open wide, obstructing blood flow from the left ventricle into the aorta. The narrowed valve allows less blood to flow through and as a result, less oxygen-rich blood is pumped out to the body, which may cause symptoms like severe shortness of breath.
With the TAVR procedure, an artificial device (see SAPIEN valve, pictured below) opens the aortic heart valve wide to allow oxygen-rich blood to flow unobstructed in one direction. The blood flows through the valve into the aorta where it then flows out to the rest of the body.
Edwards SAPIEN Transcatheter Heart Valve
FDA-approved in November 2011, the Edwards SAPIEN Transcatheter Heart Valve is the first biologic transcatheter aortic valve replacement (TAVR) therapy approved for use in the U.S. Select hospitals are now performing the procedure on qualified patients. This transcatheter procedure enables the placement of a collapsible aortic heart valve into the body via a catheter-based delivery system, which allows the valve to be inserted via the femoral artery in the thigh. The valve is designed to replace a patient’s diseased native aortic valve without traditional open-heart surgery and while the heart continues to beat – eliminating the need for cardiopulmonary bypass.
||Illustrations courtesy of Edwards Lifesciences.
That “what if” is now a reality for some patients.
Replacing a heart valve with traditional surgery would require a large incision and dividing the breastbone. However, for certain patients, a heart valve can be replaced endovascularly using a wire and a new procedure called Transcatheter Aortic Valve Replacement
, or TAVR
TAVR is a percutaneous procedure recently proven to be an appropriate alternative to standard medical care (a combination of careful observation, medications and balloon aortic valvuloplasty.) TAVR is appropriate for select patients with severe aortic stenosis (narrowing of the aortic valve opening) who are not candidates for surgery and those who are at very high risk. To be eligible for the TAVR, patients must have severe aortic stenosis
(see sidebar) and be deemed not a candidate for traditional surgery.
In the United States, TAVR continues to be studied as part of the PARTNER (Placement of Aortic Transcatheter Valves) trial
which studied inoperable patients with severe symptomatic aortic stenosis. Compared to standard medical care, among the inoperable patients who had TAVR, the procedure reduced their absolute risk of dying by 20 percent
. The risk of mortality decreased from 50 percent
to 30 percent