Please see the webpages for more details on Heart valve surgery, Mitral regurgitation, Aortic stenosis, Aortic insufficiency and Artificial heart valve. There are four main valves in the heart. Mitral valve connecting left auricle and left ventricle. Aortic valve situates in the left ventricle at the beginning of the aorta, the main artery of the human body. Tricupid valve connecting right auricle and right ventricle. Pulmonary valve situates in the right ventricle at the beginning of the pulmonary artery carrying the impure blood to the lungs. (1) The valves may adhere together, causing a narrowing of the valve opening and obstruction to the flow of blood. This is usually known as stenosis of the valve. (2) Because of the loss of elasticity and distortion of the valve the latter may not close proerly, so that a leakage or regurgitation of blood results.This is known as incompetence of the valve. Chronic rheumatic valvular disease may affect all the valves of the heart but the most commonly damaged are the mitral and aortic valves. Mitral stenosis and aortic incompetence are the conditions which most commonly arise, although mitral incompetence and aortic stenosis also occur. Quite often, mitral stenosis and aortic incompetence develop in the same person.