Interactive Guide to Physical Examination

Heart Murmurs

Heart murmurs are caused by turbulent blood flow and are distinguished from heart sounds by their longer duration. While many heart murmurs arise from structurally normal hearts, narrowed or leaky heart valves are a common pathologic cause.

When evaluating a heart murmur, several characteristics should be noted. These include: timing, configuration, location, radiation, intensity, pitch and quality of the sound.


First, decide if the murmur is occurring between S1 and S2 (systolic) or between S2 and S1 (diastolic), or if it begins in systole and continues into diastole. Systolic murmurs may be either midsystolic, late systolic, or present throughout systole (pansystolic or holosystolic). Diastolic murmurs may be early diastolic, mid-diastolic, or late diastolic. While systolic murmurs may be heard in patients with a perfectly normal heart, diastolic murmurs are classically associated with valvular pathology.


Note the configuration of the murmur, defined as its intensity over time. Some murmurs grow louder over time (crescendo murmurs), some grow less intense over time (decrescendo murmurs), others first rise and then fall in intensity (crescendo-decrescendo murmurs). Other murmurs may not vary in intensity, but rather stay constant throughout (plateau murmurs).


Find the location where the murmur is best heard and describe this location in relation to a specific thoracic landmark (e.g. an intercostal space, lower left sternal border etc.).


After locating where the murmur is best heard, auscultate around this site to determine where else, if anywhere, the murmur is transmitted. For example, some murmurs heard best at the apex radiate to the axilla or even to the posterior thorax. Similarly some murmurs heard along the left sternal border radiate to the carotids.


Rate the intensity of the murmur using a 6-point scale. Record this as a fraction where the numerator refers to the greatest intensity of the murmur heard and the denominator refers to the scale being used. For example an easily discernible murmur would be recorded as 3/6 and reported as "three over six."


Note whether the pitch is high, medium, or low.


Describe the quality of the murmur as either blowing, harsh, rumbling, or musical.

View interactive module Click on the interactive icon to practice listening to characteristics of cardiac murmurs.