Doppler study of precordial musical murmurs

Sixty-two patients with either musical (periodic, harmonic patterns) or noisy heart murmurs were examined. The murmurs were recorded by phonocardiography, which graphically records heart sounds and murmurs. Patients were also evaluated with Doppler ultrasound, an imaging and evaluation technique using sound waves. Using Doppler, the musical murmurs were all found to be caused by valvular regurgitation, a backward flow of blood through heart valves due to imperfect valves. When the Doppler probe was placed two centimeters away from the sound's origin, the signal disappeared. Doppler ultrasonography can identify the source of musical murmurs. This technique has shown that musical murmurs are usually caused by a vibrating structure.