A midsystolic murmur begins just after the S1 heart sound and terminates just before the P2 heart sound, so S1 and S2 will be distinctly audible. The term midsystolic is preferred to SEM ...

A murmur is either systolic, diastolic or continuous throughout systole and diastole. Remember that systole occurs between the S1 and S2 heart sounds, whereas diastole occurs between S2 and S1.

A third heart sound, or S3, is a low-frequency, extra heart sound that may be heard with a stethoscope right after the normal S1 and S2 heart ... Heart murmurs may be harmless ("innocent ...