Mitral valve replacement the bottom of the heart through a tube inserted in a small incision in the patient’s chest. The physician uses the tube to deploy the valve and positions it so that it rests over the heart's existing mitral valve. It is then anchored securely in place by an adjustable tether. The valve is fully retrievable, totally repositionable and is sewn onto a Nitinol frame. Nitinol is a superelastic nickel and titanium "shape memory alloy" whose flexibility eases implantation, but regains its original shape when it returns to a patient’s normal body temperature. The transition of TMVR from concept to reality
Mitral valve away from the free margin. This disposition has important effects on systolic stress distribution physiology The mitral annulus is a fibrous ring that is attached to the mitral valve leaflets. Unlike prosthetic valves, it is not continuous. The mitral annulus is saddle shaped and changes in shape throughout the cardiac cycle. The annulus contracts and reduces its surface area during systole to help provide complete closure of the leaflets. Expansion of the annulus can result in leaftlets that do not join soundly together, leading to functional mitral regurgitation. The normal diameter of the mitral annulus is , and the circumference