Tissue Doppler-derived myocardial acceleration for evaluation of left ventricular diastolic function.
OBJECTIVE
Our purpose was to evaluate a tissue Doppler-based index-peak myocardial acceleration (pACC)-during isovolumic relaxation and in evaluating left ventricular (LV) diastolic function.


BACKGROUND
Simple, practical indexes for diastolic function evaluation are lacking, but are much desired for clinical evaluation.


METHODS
We examined eight sheep by using tissue Doppler ultrasound images obtained in the apical four-chamber views to evaluate mitral valve annular velocity at the septum and LV wall. The pACC thus derived was analyzed during isovolumic relaxation (IVRT) and during the LV filling period (LVFP). We then changed the hemodynamic status of each animal by blood administration, dobutamine, and metoprolol infusion. We compared the pACC values during IVRT and LVFP over the four different hemodynamic conditions with a peak rate of drop in LV pressure (-dP/dt(min)) and the time constant of LV isovolumic pressure decay (tau), as measured with a high-frequency manometer-tipped catheter.


RESULTS
The pACC of the septal side of the mitral valve annulus during IVRT showed a good correlation with -dP/dt(min) (r = -0.80, p < 0.0001) and tau (r = -0.87, p < 0.0001). The mean left atrial pressure (LAP) correlated well with the septal side pACC during LVFP (r = 0.81, p < 0.0001). There was a weak correlation between the mitral valve annulus pACC at the LV lateral wall and mean LAP.


CONCLUSIONS
The pACC during IVRT is a sensitive, preload-independent marker for evaluation of LV diastolic function. In addition, pACC during LVFP correlated well with mean LAP.
Clinical Care Center for Congenital Heart Disease, Oregon Health and Science University, Portland, Oregon 97239-3098, USA.
Ikuo
I
Hashimoto
Aarti Hejmadi
AH
Bhat
Xiaokui
X
Li
Michael
M
Jones
Crispin H
CH
Davies
Julia C
JC
Swanson
Sebastian T
ST
Schindera
David J
DJ
Sahn
D000818:Animals; D002302:Cardiac Output; D003326:Coronary Circulation; D003971:Diastole; D015150:Echocardiography, Doppler; D005240:Feasibility Studies; D006339:Heart Rate; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006439:Hemodynamics; D015588:Observer Variation; D012756:Sheep; D016277:Ventricular Function, Left