Echocardiographic measurement of left ventricular stroke volume in newborn infants: a correlative study with pulsed Doppler and M-mode echocardiography.

Noninvasive monitoring of stroke volume by pulsed Doppler echocardiography is an important recent advance in neonatal care. Using this technique, we assessed stroke volume in 112 healthy neonates (birth weight 780-5350 g, menstrual age 27-42 weeks). Stroke volume increased with advancing birth weight (r = +0.93) and gestational age (r = +0.90). Mean stroke volume per kilogram body weight (1.77 +/- 0.28 ml/kg) was constant throughout the study population. Doppler-derived stroke volumes correlated linearly with left ventricular dimensions in diastole and in systole. Stroke volumes calculated from left ventricular dimensions using the Feigenbaum and Teichholz equations correlated equally well with Doppler-derived stroke volume values (r = +0.76 and +0.77, respectively).