title: Echographic ventricular systolic time intervals in normal term and preterm neonates.
abstract: Right ventricular and left ventricular systolic time intervals (RVSTIs and LVSTIs) were measured in normal term and preterm infants from 1 hour to 90 days of life. LVSTIs in both term and preterm infants were similar in the first five days of life. The ratio of left pre-ejection period (LPEP) to left ventricular ejection time (LVET) was lower in preterm infants older than age 5 days. Estimated gestational age had no influence on LVSTI. The ratio of right pre-ejection period (RPEP) to right ventricular ejection time (RVET) was lower in preterm infants (0.32) than in term newborns (0.37). The preterm RPEP/RVET ratio decreased with age, but at a slower rate than in term babies. This was consistent with the lower pulmonary vascular resistance present in preterm infants.
mesh_terms: D004452:Echocardiography; D004562:Electrocardiography; D005865:Gestational Age; D006339:Heart Rate; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature; D009200:Myocardial Contraction; D013599:Systole; D014655:Vascular Resistance; D016276:Ventricular Function