Left ventricular diastolic parameters in 288 normal subjects from 20 to 80 years old

Abstract
Left ventricular diastolic indexes are influenced by several variables. In order to evaluate the relationship of these indexes to age, heart rate, sex and to standard echo parameters, 288 normal subjects aged from 20 to 80 years, divided into six age groups, underwent a two-dimensional colour Doppler examination. Doppler examination was performed from the apical four chamber view to evaluate transmitral flow; isovolumic relaxation time (IVRT) was measured from an apical five chamber view. In order to obtain a sufficient number of subjects for an adequate statistical analysis, seven hospitals were involved in the study. Univariate analysis showed that age influences the peak velocity of the E (r=−0.46) and A waves (r=0.46), the E/A ratio (peak velocities) (r=−0.69), the A wave integral (r=0.48) and the E/A integral ratio (r=−0.57), the early and late filling fractions (r=−0.48 and r=0.51 respectively), and the E wave deceleration (r=−0.43) and deceleration time (r=0.36). In subjects older than 70 years an inversion of the E/A wave ratio was observed. Multivariate analysis confirmed that age has an important influence on left ventricular diastolic indexes but also demonstrated that heart rate has a significant influence. Sex, ejection fraction (EF), and the dimensions of the mitral annulus and the left ventricular posterior wall had less influence on left ventricular diastolic indexes. The mean values of E and A wave acceleration, deceleration and peak velocity were used to depict left ventricular filling morphology in various age groups for three different heart rate values. The conclusions of the study, are: (1) normal left ventricular diastolic parameters were obtained as mean values at seven different hospitals (2) when evaluating left ventricular diastolic function parameters it is important to take into account age and heart rate; E/A inversion in older subjects should be considered the normal mitral flow pattern.