On the correlation of acoustical sounds and ultrasound velocimetry in the subclavian steal syndrome.

Patients with suspected subclavian steal syndrome were examined by Doppler ultrasonography and by auscultation, particular attention being paid to the velocity profiles and "augmentation bruits" in the vertebral arteries, and the findings being compared with angiography. This was done with the patients at rest and during and after ischemic exercise of the affected arm. The recorded bruits were analyzed for their frequency content and it was found that the bruits in a particular kind of vessel are well characterized by the first moment of the spectrum.