Outcomes after Biventricular Repair Using a Conduit between the Right Ventricle and Pulmonary Artery in Infancy

Area of Science:

• Pediatric Cardiac Surgery
• Congenital Heart Disease
• Cardiovascular Surgery

Background:

• Biventricular repair is a complex procedure for congenital heart defects.
• Right ventricle to pulmonary artery (RV-PA) conduit placement is a critical step in biventricular repair for infants.
• Outcomes in very young patients (<1 year) undergoing RV-PA conduit placement require further investigation.

Purpose of the Study:

• To evaluate the outcomes of biventricular repair using RV-PA conduit in patients younger than 1 year.
• To identify risk factors for mortality, conduit reintervention, and conduit dysfunction in this patient population.
• To determine the optimal conduit size (z-score) to minimize adverse events.

Main Methods:

• Retrospective study of 141 patients (<1 year) undergoing RV-PA conduit placement between 2011-2020.
• Outcomes assessed included all-cause mortality, conduit reintervention, and conduit dysfunction (peak velocity ≥3.5 m/sec or moderate/severe regurgitation).
• Multivariable analysis and analysis of variance were used to identify risk factors and relationships between conduit z-score and outcomes.

Main Results:

• The 5-year survival rate was 89.6%. Younger age and longer cardiopulmonary bypass time were associated with mortality.
• 61 patients (43.3%) required conduit reintervention, and 68 patients (48.2%) experienced conduit dysfunction within 5 years.
• A smaller conduit z-score was a significant risk factor for both reintervention and dysfunction. Optimal z-scores were 1.3 for reintervention and 1.4 for dysfunction.

Conclusions:

• RV-PA conduit placement is a feasible surgical option for infants.
• A substantial proportion of patients require reintervention or develop conduit dysfunction.
• Utilizing a slightly oversized conduit (z-score of 1.3-1.4) may improve long-term outcomes by reducing reintervention and dysfunction rates.