[Non-invasive study of the patency of aortocoronary bypass with pulsed Doppler technic. Preliminary studies].
The pulsed Doppler effect is a non-invasive investigation technique based on the fact that the blood cells moving in a vessel on which ultrasound is incident cause a rebound of different frequency, according to their rate. This technique allows us to measure flow in a "measuring volume", whose size and depth are regulable. It is also possible to collect the signal from one or several aorto-coronary grafts, and to distinguish these from the sorrounding vasculature by their diastolic perfusion. This preliminary study (11 cases) is an attempt to formulate strict procedural criteria by comparison with follow-up arteriography of the grafts. The ease of performance of this investigation should, eventually, make it unnecessary to have to carry out repeated arteriography.