Left heart volume estimation in infancy and childhood. Reevaluation of methodology and normal values.

Left ventricular (LV) volume determinations by the area-length method were reevaluated in postmortem studies of left ventricles ranging from 0.5 to 90 cm3 absolute volume. The regression equation relating known and calculated volumes for calculated volumes <15 cm3 (V' 0.733V) was found to be significantly different from that for calculated volumes >15 cm3 (V'= 0.974V -3.1). From these equations, normal values for cinecardiographic LV end-diastolic volume (LVEDV), LV ejection fraction (LVEF), LV systolic output (LVSO), LV mass (LVM), and left atrial maximal volume (LAMax) were derived from 56 children (19 < 2 years) with normal left ventricles who underwent cardiac catheterization. Values for LVEDV/BSA were significantly less for infants (< 2 years) than for older children (42 10 versus 73 + 11 cm3/m2, P < 0.001). Values for LAMax/BSA were also less for infants than for older children (26 5 versus 38 8 cm3/m2, P < 0.001), and LVEF was significantly increasel for infants (0.68 0.05 versus 0.63 + 0.05, P < 0.01). The values for LVM/BSA (88 12 g/m2) and LVSO/BSA (4.42 + 0.95 liters/min/m2) were not significantly different for infants and older children. Multiple regression equations