What is the characteristic murmur of aortic regurgitation?

The characteristic murmur of aortic regurgitation is a diastolic decrescendo murmur. This murmur occurs due to the backflow of blood from the aorta into the left ventricle during diastole as a result of an incompetent aortic valve. The decrescendo nature of the murmur is important; it starts at its loudest point when the aortic pressure is at its peak and then gradually diminishes as the pressure gradient between the aorta and the left ventricle decreases with the filling of the heart.

The timing of this murmur is crucial. It occurs in diastole, contrasting with murmurs that occur during systole, which encompasses other options like systolic ejection murmurs, pansystolic murmurs, and mid-systolic clicks. Identifying the specific timing and quality of the murmur helps in distinguishing aortic regurgitation from other cardiac conditions.

Understanding the hemodynamics involved in aortic regurgitation and recognizing the typical auditory features during a physical examination are critical for accurate diagnosis and management in emergency medicine.