Comparison of hemodynamic data before and after corrective surgery for Down's syndrome and ventricular septal defect.

Left ventricular function and the extent of pulmonary vascular disease were studied in 18 children with Down's syndrome and 20 children without Down's syndrome who underwent corrective surgery for ventricular septal defect (VSD) and severe pulmonary hypertension. This study was conducted between 1985 and 1993. All patients underwent routine cardiac catheterization preoperatively and postoperatively (mean, 11.4 months after surgery). Left ventricular function was estimated using cineangiographic levograms. In both groups, the pulmonary-to-systemic arterial pressure ratio (Pp/Ps) and pulmonary vascular resistance (PVR) were significantly lower after surgery (P < 0.05). Postoperative improvement was more remarkable in the non-Down group (P < 0.05). Left ventricular end-diastolic volume (percent of normal) (LVEDV%N) was significantly lower after surgery in both groups (P < 0.01). The left ventricular stroke work-to-end-diastolic volume ratio (LVSW/EDV) was significantly higher after surgery in the non-Down group only (P < 0.01). Postoperative left ventricular ejection fraction (LVEF) was significantly lower in the Down group than in the non-Down group (P < 0.01). Some degree of irreversible pulmonary vascular disease was present after repair of VSD in patients with Down's syndrome. In the Down group, there were no significant changes in left ventricular function after surgery, despite the relief of volume overload. These results suggest that early diagnosis and surgical repair are key elements in the management of patients with Down's syndrome and VSD.