Murmurs Quiz

See Section. Option D describes the classic holosystolic, or pansystolic, murmur of mitral regurgitation: it lasts throughout ventricular contraction. The mitral valve normally closes to stop blood returning from the left ventricle to the left atrium. If its seal is ineffective, the ventricle can eject blood backwards as well as forwards while its pressure exceeds atrial pressure. Turbulence from that backward flow produces the murmur between the first and second heart sounds. It is usually best heard at the apex, the lower left point of the heart, and often radiates towards the axilla. This is the characteristic pattern, although some forms of mitral regurgitation have a shorter or late systolic murmur.

An early diastolic decrescendo murmur (A) reflects aortic regurgitation, with leakage into the relaxing left ventricle. The opening snap and diastolic rumble in E belong to mitral stenosis, where a narrowed valve obstructs filling rather than leaking during contraction. A carotid-radiating ejection murmur (C) suggests aortic stenosis and rises then falls as forward ejection changes. The machinery-like continuous sound in B can occur with a patent ductus arteriosus, a persistent aortic-to-pulmonary connection across which blood flows during both systole and diastole.