Aortic Stenosis, AVR and TAVR

Aortic stenosis is a disease in which the aortic valve leaflets become stiff, calcified and less “pliant”. This makes it more difficult for the left ventricle (the main pumping chamber of the heart) to eject blood. Consequently the heart muscle tries to adapt during which pressure rises within the ventricle. Ultimately, and usually after a long latency period, patients may develop chest discomfort or shortness of breath with exertion or may get lightheaded or even pass out.

Aortic stenosis is generally a disease of the elderly. Patients typically develop symptoms in their late seventies or eighties. Occasionally, patients will present earlier; these patients often have a congenitally abnormal valve (bicuspid or 2 leaflet valve, rather than the usual 3 leaflets). However, the vast majority of patients with this disease are elderly.
There is no medical treatment for this condition. There are no medicines that make the valve leaflet open more freely. Nor are there any medicines that have been shown to reliably slow the progression of the disease.

Until recently, the only therapy was surgical: aortic valve replacement. Both mechanical and bioprosthetic (tissue) valves are used, with mechanical valves generally reserved for the younger age population. The surgery is major and requires sternotomy in most instances.

Recently a new technique, TAVR, or transcatheter aortic valve replacement, has become available. With this technique, a team of cardiologists and cardiothoracic surgeons first “balloon” or stretch the native valve to create some room, and then implant a new tissue valve, all through a catheter inserted usually in through the femoral artery in the groin. The patient is spared a sternotomy and recovery time may be substantially shortened. At present this technique is restricted to patients who are judged to be high risk surgical candidates. This may very well change as we gain more experience with TAVR.