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Multicenter comparison of hybrid and Norwood procedures in patients with Fontan circulation
Kei Kobayashi1, Mary Schiff1, Laura Seese1
1Division of Pediatric Cardiothoracic Surgery, Department of Cardiothoracic Surgery, Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, Pa.
Insights
The hybrid stage 1 procedure (HS1P) shows similar long-term outcomes and cardiac magnetic resonance (CMR) findings compared to the Norwood operation in patients undergoing Fontan completion. Further research is needed to optimize patient selection for improved long-term results.
Area of Science:
- Pediatric Cardiology
- Congenital Heart Disease Surgery
- Cardiac Surgery Outcomes
Background:
- The Norwood operation is a standard initial surgical palliation for complex single-ventricle congenital heart disease.
- The hybrid stage 1 procedure (HS1P) has emerged as a potential alternative to the Norwood operation.
- Comparative data on the long-term efficacy of HS1P versus the Norwood operation is limited.
Purpose of the Study:
- To compare the outcomes of the hybrid stage 1 procedure (HS1P) with the Norwood operation in patients with single-ventricle physiology.
- To evaluate cardiac magnetic resonance (CMR) findings between the two surgical strategies.
- To assess the impact of shunt type (Sano vs. Blalock-Thomas-Taussig) within the HS1P group.
Main Methods:
- A multicenter database (Fontan Outcomes Registry) was queried for patients undergoing HS1P or Norwood operation.
- Propensity score matching was employed to create comparable cohorts.
- Composite outcomes (death, transplant, specific complications) and CMR variables were compared between groups.
Main Results:
- After propensity score matching, 76 HS1P patients and 152 Norwood patients were analyzed.
- Freedom from composite outcomes at 5, 10, and 15 years post-Fontan completion was similar between HS1P and Norwood groups (e.g., 15-year freedom: 61.2% vs. 54.7%).
- No significant differences were observed in individual composite outcome components, PA reintervention rates, or CMR/echocardiographic parameters between the matched HS1P and Norwood cohorts.
Conclusions:
- The hybrid stage 1 procedure (HS1P) demonstrates comparable long-term Fontan-era outcomes and cardiac magnetic resonance (CMR) findings to the Norwood operation in a propensity-matched multicenter cohort.
- These findings suggest HS1P is a viable alternative for initial palliation in select patients.
- Further longitudinal studies are crucial for refining patient selection criteria and optimizing long-term management strategies for single-ventricle physiology.
Objective:
The hybrid stage 1 palliation (HS1P) procedure has been proposed as an alternative to the Norwood operation. We utilized a multicenter database to compare both strategies.
Methods:
The Fontan Outcomes Registry using Clinical Examinations was queried for patients who underwent HS1P or Norwood. Propensity score matching was performed. Composite outcome (death, transplant listing, protein losing enteropathy, plastic bronchitis, atrial/ventricular tachyarrhythmia, or pulmonary artery reintervention) and cardiac magnetic resonance variables were compared. Secondary analyses compared between HS1P and shunt type (Sano vs Blalock-Thomas-Taussig).
Results:
Two hundred twenty-eight patients were analyzed (76 HS1P, 152 Norwood) after exclusion and matching. Median follow-up after Fontan was 14 years (95% CI, 13.0-15.1 years) using the reverse Kaplan-Meier method. The freedom from composite outcome was 82.3%, 74.5%, and 61.2% for HS1P patients compared with 81.4%, 69.5%, and 54.7% for Norwood patients at 5-, 10-, and 15-year follow-ups, respectively (hazard ratio, 1.02; 95% CI, 0.62-1.70; P = .9305). Individual components of the composite outcome were also similar between HS1P and Norwood in the matched cohort, including pulmonary artery reintervention. Cardiac magnetic resonance and echocardiographic parameters did not differ between groups. In a 3-group analysis of the unmatched cohort (n = 954) using Blalock-Thomas-Taussig conduit as the reference, HS1P was not associated with differences in adjusted hazard for the composite outcome or its individual components compared with Blalock-Thomas-Taussig.
Conclusions:
HS1P in those who survived to Fontan completion had comparable Fontan era outcomes and cardiac magnetic resonance findings to Norwood in a propensity matched multicenter cohort. Further longitudinal work is essential to refine patient selection and to optimize long-term outcomes.
