Purpose: Children with tetralogy of Fallot (TOF) and superior cavopulmonary anastomoses (SCPA) can have chronically elevated central venous pressure (CVP), which has been postulated to put patients at risk for cerebral ventriculomegaly. We aimed to examine cerebral ventricle size in children with these congenital heart lesions before and after surgery to determine how changes in CVP affect ventricle size.
Methods: We reviewed the records of patients who underwent SCPA or TOF repair between 2006 and 2015. Patients with pre- or post-operative cranial imaging were included. Frontal-occipital (FO) horn ratios were calculated as measures of cerebral ventricle volume. Reported normal mean FO ratio is 0.37 ± 0.03. Patient characteristics including occipito-fronto circumference (OFC) and available CVP measurements were recorded. CVP, FO ratios, and OFC percentiles were compared using paired and unpaired t tests and Wilcoxon matched pairs signed-rank test as appropriate.
Results: We reviewed 44 patients who underwent SCPA and 31 patients who underwent TOF repair who had cranial imaging studies available. In the 22 patients who underwent SCPA and had pre- and post-operative imaging, mean FO ratios significantly increased from 0.37 ± 0.03 to 0.40 ± 0.04 (P < 0.001). In contrast, in the seven patients with TOF with pre- and post-operative imaging, FO ratio was elevated at baseline and remains so after surgical repair, 0.43 ± 0.08 to 0.42 ± 0.08 (P = 0.65). Similar patterns were noted with OFC percentiles, which were significantly increased as compared to baseline after SCPA (P < 0.001) but were not significantly changed after TOF repair (P = 0.58). Finally, when available, preoperative and postoperative CVP measurements of all patients were examined, CVP increased in patients who underwent SCPA, from 6.5 ± 2 mmHg preoperatively to 9.1 ± 2.3 mmHg postoperatively (P < 0.001), while CVP remained statistically unchanged in patients who underwent TOF repair, 12.9 ± 3.3 mmHg preoperatively to 14.4 ± 3.1 mmHg postoperatively (P = 0.2).
Conclusion: Cerebral ventriculomegaly was observed in patients with SCPA and TOF, and the observed changes in FO ratio and OFC may be related, at least in part, to CVP.
Keywords: Central venous pressure; Congenital heart defects; Pediatric; Tetralogy of Fallot; Ventriculomegaly.