Q. Physical Signs of mitral regurgitation?
Pulse is of normal character but carotid upstroke may be brisk. Atrial fibrillation is often present in a patient with advanced disease. Blood pressure is normal. Jugular venous pressure is normal in compensated phase. Left ventricle is often dilated with a downward and laterally displaced forcible apex. A systolic left para sternal lift may be palpable as the regurgitant blood enters the left atrium and this is different from para sternal lift due to prominent right ventricle.
Occasionally systolic thrill of mitral regurgitation is palpable. First heart sound (S1) is usually soft in rheumatic mitral regurgitation but it is normal in mitral valve prolapse. Second heart sound (S2) may be widely split. A third heart sound (S3) may be palpable at the apex. A fourth heart sound (S4) may be seen with recent onset severe mitral regurgitations and sinus rhythm. A holosystolic murmur starting with S1 and ending with S2 due to mitral regurgitation is audible at apex. In mitral valve prolapse it is a mid systolic murmur starting after a mid systolic click.
Murmur radiates to axilla and back with a posteriorly directed jet as seen with anterior leaflet abnormalities, ischaemic and dilated cardiomyopathies. It radiates superiorly and medially towards base with posterior leaftlet abnormalities. Patients with severe mitral regurgitation due to valve pathology have loud and long murmurs while soft, short, barely audible early murmurs are present in patients with functional mitral regurgitation. Murmur is often not audible in patients with acute mitral regurgitation. Physical maneuvers like valsalva, squatting and respiration will help in differentiating it form other systolic murmurs. Mid diastolic murmur may follow an S3 especially in rheumatic mitral regurgitation and is unusual in mitral regurgitations of other etiologies.