Increasing Use of the Right Ventricle to Pulmonary Artery Shunt for Stage 1 Palliation: A Report from the National Pediatric Cardiology Quality Improvement Collaborative
Scott Wirth, MD; Haleh Heydarian, MD; Elisa Marcuccio, MD; Brooke Tepe, RN; Laurel Stein, RN; Garick Hill, MD
Background: Stage 1 palliation (S1P) of single ventricle heart defects with aortic hypoplasia consists of either the Norwood operation with a modified Blalock-Taussig shunt (MBTS) or a right ventricle-to-pulmonary artery shunt (RVPAS), or a hybrid procedure. Changes in national trends over time and factors influencing surgical approach remain unclear.
Objective: We aimed to assess changes in type of S1P utilized over time and associations between patient- and center-dependent risk factors and type of S1P performed. Additionally, we aimed to compare outcomes between types of S1P performed.
Methods: Data from the National Pediatric Cardiology Quality Improvement Collaborative (NPC- QIC) phase 1 (6/2008-8/2016) and phase 2 (8/2016-9/2019) databases were used. S1P type was evaluated by year of operation. Factors influencing the choice of MBTS versus RVPAS, as well as length of stay after S1P and death/transplant rates prior to Stage 2 palliation (S2P) between shunt types, were evaluated. Sites were stratified by the number of patients in the database per year as small (<5), medium (<10) and large (≥10) centers.
Results: The combined database included 3335 eligible patients; 1,028 (30.8%) with MBTS, 1,989 (59.7%) with RVPAS, and 318 (9.5%) with hybrid procedure. Overall, of 62 centers, 14.6% of S1P were at small centers (n=26), 40.6% at medium centers (n=24), and 44.7% at large centers (n=12). There was an increase in RVPAS use over time (p=0.02). In multivariable analysis, increasing hospital volume (OR 1.2 [95% CI 1.1-1.4], p=0.003) and absence of other organ system anomalies (OR 1.5 [95% CI 1.0-2.2], p=0.049) were associated with MBTS use over RVPAS. Median length of stay after S1P with MBTS was longer than with RVPAS (31 [95% CI 20-49] vs 29 [95% CI 19-47] days, p=0.054) and death/transplant rate was higher prior to S2P (12.3% vs 9.6%, p=0.03).
Conclusions: Use of RVPAS with S1P has increased over time with a decrease in MBTS use and unchanged hybrid frequency. MBTS is used more commonly in centers with higher volume and in patients without other anomalies but is associated with longer post-op hospitalization and lower transplant-free survival to stage 2 palliation.