Master Mitral Regurgitation with Picmonic for Medicine

Mitral regurgitation, also called mitral insufficiency, is a heart disorder in which the mitral valve does not properly close when the heart pumps blood. The mitral valve is a bicuspid valve that lies between the left atrium and the left ventricle. During diastole, the mitral valve normally opens allowing the left ventricle to fill with blood. At the end of diastole, the mitral valve closes to prevent reversal of blood flow back into the left atrium. Mitral regurgitation is characterized by a faulty mitral valve that cannot fully close during systole, which allows blood to flow back into the left atrium rather than being pumped forward through the aorta. The regurgitant blood flow causes a characteristic holosystolic blowing heart murmur that is heard loudest at the apex of the heart with radiation towards the axilla. This murmur is increased when there is increased total peripheral resistance like during squatting or hand grip due to higher pressures that the left ventricle must pump against resulting in increased regurgitant blood flow. This left sided valvular disease can be distinguished from right sided tricuspid regurgitation because it becomes louder during expiration due to increase in venous return from the pulmonary veins to the left heart resulting in a large volume of blood that flows back to the left atrium. Mitral regurgitation is often a congenital condition or a consequence of rheumatic heart disease, marked left ventricular dilatation, or papillary muscle dysfunction secondary to myocardial infarction.