Influence of body size and age on maximal diastolic velocity of mitral annulus motion.

Background: Maximal long-axis relaxation velocity (RVm), measured from the mitral annulus motion (MAM), has recently been suggested as an index of left ventricular (LV) diastolic function. M-mode recording and pulsed tissue Doppler have been used. Regarding the M-mode method, reference values have not been presented previously. In the current study, therefore, the influence on RVm of such variables as age, body size, heart rate, and blood pressure was investigated to obtain adequate reference values. Methods and Results: Fifty-seven healthy subjects were included in the study. RVm was recorded by M-mode echocardiography from apical 4- and 2-chamber views from 4 sites of the mitral annulus. Multiple regression analysis showed that heart rate ought to be taken into account when reference values are calculated for children and adolescents, and age must be considered in adults. For reference values in children and adolescents, the following equation is suggested: RVm = 171 − 0.54 × heart rate (SEE = 18.7). In adults over 18 years, the suggested equation is RVm = 163 − 1.29 × age (SEE = 8.4.) (J Am Soc Echocardiogr 2002;15:29-35.)