A dramatic learning curve of extracardiac Fontan operation in the modern era.

BACKGROUND

This study aimed to describe the learning curve of the extracardiac Fontan procedure in a single center and to analyze the changes in clinical applications and outcomes.

METHODS

A retrospective chart review of all extracardiac Fontan patients in a single tertiary care center was undertaken. Patients with a diagnosis of hypoplastic left heart syndrome and those who had undergone a lateral tunnel modification, intra/extracardiac Fontan, Kawashima procedure, or inferior vena cava-to-azygous vein connection were excluded from the analysis.

RESULTS

Between May 2004 and February 2018, data of 159 extracardiac Fontan patients were analyzed. The median age was 5.5 years (range 4.5-8.2 years). Based on a cumulative sum analysis, a hinge point was determined to divide the cohort into 2 phases. Phase 1 ( n = 70) represented the first learning phase and phase 2 ( n = 89) represented the later phase. Mortality decreased in phase 2 (2/89; 2%) compared to phase 1 (10/70; 14%; p = 0.004). Two (3%) patients had extracorporeal membrane oxygenation in phase 1, and 5 (6%) in phase 2 ( p = 0.47). More patients in phase 2 underwent a prior bidirectional Glenn procedure (83/89 vs. 57/70; p = 0.02), fenestration (80/89 vs. 9/70; p < 0.001), and pulmonary artery reconstruction (37/89 vs. 2/70; p < 001).

CONCLUSIONS

This study shows that increased use of extracorporeal membrane oxygenation, strict implementation of the three-stage management plan, routine fenestration, and a low threshold for pulmonary artery reconstruction may be associated with decreased mortality in the extracardiac Fontan procedure.