[Doppler ultrasound determination of pressure decrease in model peripheral arterial stenoses].

In a pulsatile in vitro flow model with mounted concentric peripheral arterial stenoses, we compared the mean trans-stenotic pressure difference between pre- and poststenotic segment with the Doppler-estimated mean pressure gradient calculated according to the simplified Bernoulli equation applied over an entire stroke cycle. A close linear correlation was found between Doppler-estimated and invasively measured pressure drop values: Y = 1.13X + 0.47 (r = 0.98, SEE = 1.4 mmHg, n = 16). The Doppler-derived overestimation of the invasively measured mean pressure-drop by an average of 16% (absolute values 2.2 +/- 1.7 mmHg) suggests that in this in vitro model a small part of the kinetic energy of the stenotic jet is recovered distal to the poststenotic turbulences. The difference between both methods is so little that the Doppler-estimated mean pressure drop is acceptable in concentric peripheral model arterial stenoses.