Assessment of an automatic determination of left ventricular dP/dt from Doppler spectra of mitral regurgitation

摘要

Left ventricular (LV) pressure can be derived noninvasively from the continuous wave Doppler spectra of a mitral regurgitation using the simplified Bernoulli equation. The peak of its first derivative (dP/dt) reflects LV systolic function. Presently, it can be computed on profiles digitised tediously by hand tracings. This paper describes an evaluation of peak dP/dt based on the automatic determination of the contour of regurgitant velocity profiles after digitisation of raw Doppler signals with an A/D board and a PC. This method has been validated in vitro on a pulse duplicator in which a leaking mitral prosthesis was studied under several hemodynamic conditions. The Doppler derived peak dP/dt was well correlated (r/sup 2/=0.9, SEE=251 mmHg) with the measured one. Also recordings on patients showed a good correlation with the mean (1-3 m/s) dP/dt (r/sup 2/=0.7. SEE=365 mmHg), showing a systematic underestimation (199/spl plusmn/176 mmHg). In conclusion, our method is an easy and reliable tool to measure peak LV dP/dt.