Heart Sounds & Murmurs
Improve your auscultation skills by listening to and learning about normal heart sounds and common heart murmurs.
Understanding heart sounds
S1 ("lub") is produced by closure of the mitral and tricuspid valves at the beginning of systole. S2 ("dub") is produced by closure of the aortic and pulmonary valves at the end of systole.
What are heart murmurs?
Heart murmurs are sounds caused by turbulent blood flow during the cardiac cycle. They can occur with increased flow, narrowed or leaking valves, or abnormal connections between chambers.
- Systolic murmurs occur between S1 and S2.
- Diastolic murmurs occur between S2 and S1.
- Murmurs are described by timing, intensity, quality, pitch, location, radiation, and shape.