Decreasing Interstage Mortality After the Norwood Procedure: A 30-Year Experience

Area of Science:

• Pediatric Cardiology
• Congenital Heart Surgery
• Critical Care Medicine

Background:

• Hypoplastic left heart syndrome (HLHS) poses high interstage mortality risks between initial and subsequent surgical procedures.
• The superior cavo-pulmonary connection (SCPC) is a critical palliative step for HLHS infants.
• Optimizing the period between the Norwood procedure and the SCPS is vital for improving outcomes.

Purpose of the Study:

• To compare interstage mortality rates in HLHS patients across four distinct eras (1988-2017).
• To identify factors influencing interstage mortality in HLHS patients undergoing the Norwood procedure and awaiting SCPS.
• To evaluate the impact of evolving surgical and medical management on HLHS interstage outcomes.

Main Methods:

• Retrospective analysis of 1111 HLHS patients who underwent the Norwood procedure and were eligible for SCPS.
• Stratification of patients into four eras based on changes in management protocols.
• Logistic regression models used to assess risk factors for interstage mortality.

Main Results:

• Overall interstage mortality was 10.8% (120/1111 patients).
• The most recent era (era 4) demonstrated significantly lower mortality (4.6%) compared to the earliest era (13.4%).
• Reduced age at SCPS, introduction of an interstage monitoring program, and increased use of the right ventricle to pulmonary artery (RVPA) shunt were associated with decreased mortality.

Conclusions:

• Interstage mortality for HLHS has significantly decreased over a 30-year period.
• Key factors contributing to improved survival include earlier SCPS, dedicated interstage monitoring, and RVPA shunt utilization.
• These findings underscore the importance of optimized care pathways for HLHS patients.