Diastolic left ventricular function in normal children: the maximal positive dD/dt compared with the E/A ratio of mitral flow pattern.

The normal values for left ventricular diastolic function in children are influenced by numerous factors. As an index of this function, the maximum velocity of left ventricular internal dimension expansion (+ max dD/dt) was calculated from M-mode echocardiography for 33 normal persons who ranged in age from seven days to 18 years. This index showed a linear correlation with left ventricular end-diastolic dimension in the resting state. This index was compared with the E/A ratio which is ordinarily used as the diastolic functional index for children. Considering changes in physical development during childhood, both indices showed similar trends in relation to body surface area. The E/A ratio was strongly influenced by heart rate, but + max dD/dt was not. This was the major difference between two indices.