title: [Doppler ultrasound evaluation of aortic insufficiency using half-pressure time. Absence of arterial rigidity influence].
abstract: In 20 patients with pure aortic regurgitation we studied the relationship between the severity of regurgitation, as assessed haemodynamically by the percentage of leakage (%L), and the half-pressure (T 1/2 P) and half-velocity (T 1/2 V) times, as obtained from doppler aortic blood velocity curves, taking into account the rigidity of the systemic vascular circuit characterized by the pressure wave propagation velocity (PWPV). The systemic arterial circuit was supple in 14 patients (PWPV less than 7.5 m/sec) and rigid in 6 patients (PWPV greater than 7.5 m/sec). The regression slopes between %L and T 1/2 P and between %L and T 1/2 V were calculated with their confidence limits in the 14 patients with supple arteries. The 6 patients with rigid arteries fitted into this nomogram, thus demonstrating that systemic arterial rigidity makes no difference in the relationship between %L and doppler indices. The half-velocity and half-pressure times measured by doppler ultrasound were acquired from a velocity signal directly determined by the aortic regurgitation, without any detectable effect of vascular circuit rigidity. Being equivalent by nature to the signal decrease time constant, they are independent of the absolute protodiastolic value of diastolic pressure gradient or blood flow velocity. For this reason these two doppler parameters are reliable to evaluate the severity of aortic regurgitation.
authors.affiliation: CSK académie médicale, service de cardiologie, Varsovie, Pologne.
authors.forename: H
authors.initials: H
authors.lastname: Kalotka-Bratek
authors.forename: G
authors.initials: G
authors.lastname: Drobinski
authors.forename: K
authors.initials: K
authors.lastname: Klimczak
authors.forename: P
authors.initials: P
authors.lastname: Busquet
authors.forename: J B
authors.initials: JB
authors.lastname: Fraysse
authors.forename: A
authors.initials: A
authors.lastname: Bejean-Lebuisson
authors.forename: Y
authors.initials: Y
authors.lastname: Grosgogeat
mesh_terms: D000328:Adult; D000368:Aged; D001022:Aortic Valve Insufficiency / Q000175:diagnosis* / Q000503:physiopathology; D001783:Blood Flow Velocity; D001794:Blood Pressure; D015150:Echocardiography, Doppler; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D014655:Vascular Resistance
vernacular_title: Evaluation doppler de l'insuffisance aortique par le temps de demi-pression. Absence d'influence de la rigidité artérielle.