Univentricular repair: is routine fenestration justified?

BACKGROUND: A decade after the introduction of baffle fenestration, the outcome of Fontan-type repair for hearts with a functional single ventricle finally looks promising. Our study was designed to assess the impact of fenestration on the outcome of univentricular repairs.

METHODS: From January 1988 to December 1997, 348 patients (104 with tricuspid atresia and 244 with other morphological diagnoses) underwent univentricular repair at our institute. Since 1994, routine fenestration of the atrial baffle was performed in all patients (n = 126).

RESULTS: The overall Fontan failure rate was 14% (50 of 348) and included 45 early deaths and five Fontan take downs. Absence of fenestration was the only and highly significant predictor of Fontan failure (risk ratio [RR] 3.3, 95% confidence interval [CI] 1.49 to 7.31, p = 0.002). Significant pleural effusion was seen in 27% of patients. Absence of fenestration of the atrial baffle (RR 3.97, 95% CI 2.17 to 7.26, p < 0.001) and aortic cross-clamp time more than 60 minutes (RR 2.15, 95% CI 1.3 to 3.5, p = 0.002) were found to be significant risk factors. The follow-up ranged from 6 to 120 months (mean 46.0 +/- 18.0 months). There were 12 late deaths and 5 patients were lost to follow-up. Actuarial survival (Kaplan Meier) at 90 months was 81% +/- 4%. Two hundred and fifty-eight patients (90%) were in New York Heart Association class I at their last follow-up visit. Oxygen saturation in the fenestrated group ranged from 85% to 94% (mean 89%). Thirty patients (26%) had spontaneous closure of the fenestration over a mean period of 34 months, and there has been no incidence of late systemic thromboembolism. In no instance has there been a need to close the fenestration.

CONCLUSIONS: Elective fenestration of the intraatrial baffle is associated with decreased Fontan failure rate and decreased occurrence of significant postoperative pleural effusions. Routine elective fenestration of the atrial baffle may, therefore, be justified in all univentricular repairs.