EFFECTS OF RESPIRATION ON LEFT-VENTRICULAR DIASTOLIC FUNCTION IN HEALTHY-CHILDREN

Pulsed Doppler echocardiographic indices of mitral valve filling were measured in 20 healthy children, between 3 and 12.5 years old, in orde r to evaluate the effects of spontaneous respiration on left ventricul ar diastolic filling patterns. There were significant respiratory vari ations in four parameters of left ventricular diastolic function: The peak early filling velocity, the ratio of early to late peak filling v elocity, and the ratio of early to late diastolic velocity-time integr al decreased significantly during inspiration (mean decrease 7%, P < 0 .05; 16%, P < 0.01; and 12%, P < 0.05, respectively). On the other han d there was a significant increase in late peak filling velocity with inspiration (10% increase, P < 0.05). Other variables of left ventricu lar diastolic filling were unchanged with inspiration. These results s uggest that assessment of left ventricular diastolic function in child ren should be standardized with regard to respiratory phases in any cl inical application.