Learning Objectives

Differentiate between systolic, diastolic, and continuous murmurs. Identify the classic auscultation findings and radiation patterns for major valvular lesions. Correlate murmurs with pathophysiological triggers like chordae tensing or fused leaflet tips. Recognize high-yield clinical associations such as SAD symptoms or rheumatic fever sequelae.

Systolic Murmurs

Systolic murmurs occur between S1 and S2. They can be ejection-type (crescendo-decrescendo) or holosystolic.

Aortic Stenosis (AS):

Crescendo-decrescendo ejection murmur heard at the base; radiates to carotids. Associated with the “SAD” triad (Syncope, Angina, Dyspnea) and Pulsus parvus et tardus. In AS, LV pressure > aortic pressure during systole.

Mitral/Tricuspid Regurgitation (MR/TR):

Holosystolic, high-pitched “blowing” murmur. MR radiates to the axilla (often post-MI or MVP); TR is heard at the tricuspid area (often due to RV dilation).

Mitral Valve Prolapse (MVP):

Late systolic crescendo murmur with a midsystolic click (MC). The click is due to the sudden tensing of the chordae tendineae as leaflets prolapse into the LA.

Ventricular Septal Defect (VSD):

Harsh holosystolic murmur loudest at the tricuspid area. Smaller VSDs typically produce higher intensity murmurs than larger ones.

Diastolic Murmurs

Diastolic murmurs occur after S2 and are often clinically significant.

Aortic Regurgitation (AR):

High-pitched, decrescendo “blowing” murmur. Presents with a hyperdynamic pulse, head bobbing, and wide pulse pressure.
Commonly caused by “BEAR”: Bicuspid aortic valve, Endocarditis, Aortic root dilation, or Rheumatic fever.

Mitral Stenosis (MS):

Delayed rumbling mid-to-late murmur following an opening snap (OS). The OS is caused by the abrupt halt of fused leaflet tips during diastole. Highly specific for rheumatic fever; LA pressure >> LV pressure during diastole.

Continuous Murmurs

These murmurs persist throughout both systole and diastole.

Patent Ductus Arteriosus (PDA):

Continuous machine-like murmur loudest at S2; best heard in the left infraclavicular area. Often associated with prematurity or congenital rubella.

Activity