When is a diastolic murmur audible?

A diastolic murmur is audible during diastole, which is the phase of the cardiac cycle when the heart relaxes and fills with blood. During diastole, the heart chambers, particularly the ventricles, are in a state of rest, allowing for the passive filling of blood from the atria. If there are any abnormalities in the heart structures, such as aortic regurgitation or mitral stenosis, turbulent blood flow can lead to murmurs being produced during this resting phase.

The specific timing of the cardiac cycle is critical in understanding when these murmurs occur. Unlike systole, where the heart actively pumps blood out to the body and any interference or abnormal flow would produce different types of sounds, diastolic murmurs result from the conditions present when the heart is filling with blood. Recognizing this distinction between the phases of the heart cycle is essential for identifying and interpreting heart sounds during a clinical assessment.