Long-term Outcomes of Tetralogy of Fallot: A Study From the Pediatric Cardiac Care Consortium

Abstract

Importance: Tetralogy of Fallot (TOF) is a surgically repairable form of cyanotic congenital heart disease. Multicenter data for long-term survival following repair are sparse.

Objective: To evaluate the long-term transplant-free survival of TOF by surgical strategy adjusted for era and patient characteristics.

Design, setting, and participants: Retrospective cohort study enriched with data from the National Death Index and the Organ Procurement and Transplantation Network through 2014. Multicenter cohort from the Pediatric Cardiac Care Consortium (PCCC), a large, US-based clinical registry for interventions for congenital heart disease. The cohort included patients with adequate identifiers for linkage with the National Death Index and the Organ Procurement and Transplantation Network who were enrolled in the PCCC registry between 1982 and 2003 and survived surgical repair of simple TOF. Data were analyzed between September 2015 and April 2018.

Exposures: We examined patient-associated and surgery-associated risk factors affecting survival.

Main outcomes and measures: We analyzed the transplant-free survival during early (<6 years) and late (≥6 years) phase after TOF surgical repair.

Results: Of the 3283 patients who survived repair for simple TOF and met the study's inclusion criteria, 56.4% were male and 43.6% were female. Twenty-five-year survival following TOF repair was 94.5%. Multivariable analysis demonstrated increased risk of early mortality with staged repair (HR, 2.68; 95% CI, 1.59-4.49) and non-valve-sparing operation (HR, 3.76; 95% CI, 1.53-9.19). Presence of a genetic abnormality was associated with increased risk of death both in the early (HR, 3.64; 95% CI, 2.05-6.47) and late postoperative phase (HR, 4.41; 95% CI, 2.62-7.44).

Conclusions and relevance: Long-term survival after simple TOF repair is excellent. Staged repair and non-valve-sparing operations were negatively associated with survival in the early postrepair phase but not the late postrepair phase. These data are important for patients with repaired TOF and their caretakers and may guide surgical strategies for optimizing the long-term outcomes of this population.

Figure 1.. Kaplan-Meier Survival Curve and Hazard of Mortality/Transplant Curve Following Discharge From Definitive TOF Repair

A, Transplant-free survival following TOF repair. Red dots represent the nonparametric Kaplan-Meier survival estimates. The solid black line is the estimated parametric survival model. Dashed lines represent the 95% confidence limits for the parametric survival estimates. B, Hazard of mortality/transplant following discharge from definitive TOF repair. Hazard function shows an early peaking hazard that rapidly decreases during the first year and reaches a minimum at 4 years following discharge followed by an increasing late hazard period through 30 years following TOF repair. Insert: zoomed view of the hazard function that shows the trough of the hazard around 6 years followed by a slow steady increase throughout the follow-up period. The dotted line at 6 years for both Figures represents division between early and late deaths.

Figure 2.. Stratified Transplant-Free Survival Plots of Survivors of TOF Repair by Variables of Interest

A, Sex (m = male; f = female); B, Age at time of TOF repair; C, Primary repair vs staged repair strategy; D, Valve-sparing vs non–valve-sparing approach; E, Genetic condition; F, Era of repair. Shaded area illustrates the 95% confidence intervals.