Fontan with lateral tunnel is associated with improved survival compared with extracardiac conduit

The study aim was to compare Fontan patients undergoing lateral tunnel (LT) versus extracardiac conduit (ECC) technique.

Fontan patients (LT vs ECC) from January 2000 to December 2017 were analyzed retrospectively. Baseline characteristics were analyzed as covariates. Primary outcomes (ie, mortality, Fontan failure, thrombosis, and pacemaker implantation) were compared using time-to-event models. Subgroup analysis including only initially fenestrated cases and propensity score matching were performed.

Eight hundred one Fontan patients: LT (n = 638) versus ECC (n = 163) were included. Median follow-up time was 4.8 years (range, 1.1-10.8 years). Baseline characteristics were similar except for age: LT versus ECC: 2.6 years (range, 2.2-3.2 years) versus 3.1 years (range, 2.6-4.7 years) (P < .01) and mean pulmonary artery pressure: LT versus ECC: 12 mm Hg (11-15 mm Hg) versus 11 mm Hg (10-13 mm Hg) (P < .05). Early mortality was significantly higher in ECC versus LT group (3.1%; vs 0.5%; P < .05). Freedom from death, heart transplantation and Fontan failure were significantly longer in LT vs ECC (P < .01). After correcting for age, diagnosis, surgical technique, surgeon, mean pulmonary artery pressure, and fenestration, the ECC group showed worse freedom from death (hazard ratio, 2.8; P < .01) and Fontan failure (hazard ratio, 3.0; P < .01). No difference in pacemaker implantation rate was demonstrated (P = .25). Early fenestration closure was associated with higher risk of early (hazard ratio, 30.5) and late mortality (hazard ratio, 3.5). After matching, log-rank tests showed significant differences between the 2 groups for Fontan failure at 5 and 10 years (P < .01) and mortality at 5 years (P = .02).

When compared with ECC, LT Fontan is associated with better short and midterm outcomes. Spontaneous fenestration closure is an independent risk factor for early/late mortality.