Surgical Valve Intervention Impact on Tricuspid Regurgitation in Single Ventricle Reconstruction

Overview

In patients with single right ventricle anomalies undergoing staged surgical palliation, tricuspid regurgitation (TR) severity increases after the Norwood procedure and remains stable through age 6. Surgical tricuspid valve interventions and TR severity are associated with transplant-free survival, with right ventricular function modestly affected by TR severity post-Norwood.

Background

Tricuspid valve regurgitation is common in single right ventricle anomalies and negatively impacts survival and transplant rates. Mechanisms include leaflet tethering, clefts, annular dilation, and prolapse. The Single Ventricle Reconstruction (SVR) trial followed infants undergoing Norwood procedures to evaluate outcomes related to TR severity and surgical interventions. Understanding TR progression and intervention effects is critical to improving long-term outcomes in this population.

Data Highlights

Key Findings

• The proportion of patients with > mild TR significantly increased from 12.1% at baseline to 24.3% post-Norwood (p < 0.001).
• The prevalence of > mild TR remained stable through subsequent echocardiograms up to 6 years of age.
• Among transplant-free survivors, 50% had ≤ mild TR at all echocardiograms, while only 1% had consistently > mild TR.
• Post-Norwood, patients with ≤ mild TR had modestly better right ventricular ejection fraction (47% vs. 45%, p = 0.005) and fractional area change (37% vs. 35%, p = 0.02) compared to those with > mild TR.
• Baseline TR severity was not consistently associated with right ventricular size or function at later time points.
• Surgical tricuspid valve interventions and TR severity were associated with transplant-free survival, highlighting the clinical importance of valve management.

Clinical Implications

Monitoring TR severity closely after the Norwood procedure is essential, as TR worsens early and then stabilizes. Surgical intervention on the tricuspid valve may influence survival outcomes, suggesting that timely valve management could improve long-term prognosis. Right ventricular function shows modest differences related to TR severity post-Norwood, emphasizing the need for integrated assessment of valve and ventricular status.

Conclusion

Tricuspid regurgitation severity increases after the Norwood procedure and remains stable through early childhood in single right ventricle patients. Surgical valve interventions and TR severity are important factors influencing transplant-free survival, underscoring the need for targeted management strategies.

References

1. SVR Trial Investigators 2010 -- Single Ventricle Reconstruction Trial Design and Outcomes
2. SVR Trial Follow-up 2016 -- Transplant-Free Survival and Echocardiographic Outcomes
3. Echocardiographic Core Lab Analysis 2018 -- RV Remodeling and Function in SVR Cohort