title: [Evaluation of left ventricular relaxation by mitral regurgitant curve].
abstract: To examine whether left ventricular (LV) isovolumic relaxation can be assessed noninvasively using a continuous-wave Doppler technique, we compared Doppler-determined parameters derived from mitral regurgitation (MR) velocity curve with micromanometer-derived indices of LV relaxation, peak negative dP/dt and tau, in 9 patients with MR (5 with dilated cardiomyopathy, 2 with old myocardial infarction and 2 with rheumatic MR). The rate of LV pressure decay (delta P/delta t) at aortic valve closure was calculated from the recordings of MR jet velocities based on the simplified Bernoulli equation. The time constant of LV pressure decay (tD) was determined as the time from the aortic valve closure to the point where the velocity declined by (1/e)1/2. Doppler-determined delta P/delta t correlated well with hemodynamic peak negative dP/dt (r = 0.97, p < 0.001), and tD with hemodynamic tau (r = 0.89, p < 0.005). Thus, we concluded that left ventricular isovolumic relaxation can be noninvasively assessed with a continuous-wave Doppler technique in the presence of mitral regurgitation.
authors.affiliation: First Department of Medicine, Osaka University School of Medicine.
authors.forename: Y
authors.initials: Y
authors.lastname: Doi
authors.forename: J
authors.initials: J
authors.lastname: Tanouchi
authors.forename: K
authors.initials: K
authors.lastname: Yamamoto
authors.forename: J
authors.initials: J
authors.lastname: Naito
authors.forename: M
authors.initials: M
authors.lastname: Uematsu
authors.forename: T
authors.initials: T
authors.lastname: Masuyama
authors.forename: A
authors.initials: A
authors.lastname: Kitabatake
authors.forename: T
authors.initials: T
authors.lastname: Kamada
mesh_terms: D001783:Blood Flow Velocity; D001794:Blood Pressure; D003971:Diastole; D015150:Echocardiography, Doppler; D006801:Humans; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging / Q000503:physiopathology*; D009200:Myocardial Contraction; D016277:Ventricular Function, Left / Q000502:physiology*