Congestive heart failure during early infancy in patients with ventricular septal defect relative to early closure.

The hemodynamic features of 44 patients requiring surgical closure of a ventricular septal defect (VSD) during early infancy were evaluated. The VSD was closed within the first 6 months of life in 29 patients (group A) and during the second 6 months in 15 patients (group B). The left-to-right (L-R) shunts were significantly greater in group A than in group B, although in all patients they were more than 50%. In contrast, the left ventricular end-diastolic volume was significantly greater in group B than in group A, whereas the right ventricular end-diastolic volume was greater in group A; the difference was not statistically significant. The step-up in blood oxygen saturation in the lower right atrium, which was significantly more in group A, indicated the L-R shunt across the patent foramen ovale (PFO). The L-R shunt across the VSD during diastole was also detected in all patients angiographically. With early infantile VSD, the larger the L-R shunt the greater was the likelihood of early surgery. Right ventricular volume overload caused by the L-R shunt across a PFO as well as through the VSD during diastole is a useful indicator of a large shunt in infants with VSD.