[A simplified method of continuous-wave Doppler noninvasive assessment of ventricular relaxation in mitral insufficiency].
OBJECTIVE
The minimum value of dP/dT is a parameter of diastolic function that can be estimated noninvasively by analyzing the profile of velocity of the mitral regurgitant jet, recorded by continuous-wave Doppler. This estimation requires a complex analysis of the curves that impedes its practical use. Our objective was to validate a simplified method to estimate noninvasively the value of dP/dTmin when mitral regurgitation exists. We calculated the pendient of the profile of velocity of the curve of mitral regurgitation during its deceleration, between 3 and 1.5 m/s, an interval that defines a difference in pressure using the formula delta p = (4v2(1) - 4v2(2)). We divided this interval by the time needed by the jet to decelerate from 3 to 1.5 m/s, obtaining the rate of pressure decay, in mmHg/s.


METHODS
We provoked mitral regurgitation in five pigs and registered dP/dT and the curve velocity of mitral regurgitation simultaneously, by micromanometer-tipped catheter and continuous-wave Doppler, respectively. The rate of pressure decay was calculated on the mitral regurgitation curve.


RESULTS
We obtained 29 simultaneous registers. The coefficient for the correlationship between dP/dT and the rate of pressure decay was with an r value of 0.62 (p < 0.0001). The rate of pressure decay underestimated systematically the value of dP/dT. Intra and interobserver variability of TDP was 9 and 11%, respectively.


CONCLUSIONS
This study validates a simplified method to estimate dP/dT noninvasively, with acceptable correlation with invasive measurements and adequate reproducibility.
Sección de Cardiología del Hospital Universitario de Guadalajara, Universidad de Alcalá.
J A
JA
García Lledó
J L
JL
Moya Mur
J
J
Balaguer Recena
E
E
Novo García
C
C
Correa Gorospe
P
P
Jorge
R
R
Barea Navarro
L
L
Boquete
D000818:Animals; D003627:Data Interpretation, Statistical; D003971:Diastole; D015150:Echocardiography, Doppler; D008944:Mitral Valve Insufficiency / Q000503:physiopathology*; D015588:Observer Variation; D015203:Reproducibility of Results; D013552:Swine; D016276:Ventricular Function / Q000502:physiology*; D017725:Ventricular Pressure / Q000502:physiology
Método simplificado para el análisis no invasivo de la relajación ventricular mediante Doppler continuo en la insufficiencia mitral.