Mitral valve stenosis the pressures in the left atrium and the left ventricle during ventricular diastole will be equal. The result is that the left ventricle gets filled with blood during early ventricular diastole, with only a small portion of extra blood contributed by contraction of the left atrium (the "atrial kick") during late ventricular diastole. When the mitral valve area goes below 2 cm, the valve causes an impediment to the flow of blood into the left ventricle, creating a pressure gradient across the mitral valve. This gradient may be increased by increases in the heart rate or cardiac output. As the
Mitral valve replacement biological or mechanical valve. The left artium is then closed, and the patient weaned from cardiopulmonary bypass. After surgery patients are typically taken to an intensive care unit (ICU). There are two primary types of artificial mitral valves: mechanical valves and bioprosthetic tissue (biological) valves. The mechanical valves are made from metal and pyrolytic carbon, and can last a lifetime. Patients with mechanical valves must take blood-thinning medications to prevent clotting. Bioprosthetic valves are made from animal tissues. Use of these biological valves allows patients to avoid blood thinners. However, the bioprosthetic valves may only last 10 to 15 years.