Mid-term prognosis and risk stratification in patients with post-operative pulmonary hypertension: Insights from the Japanese Association of Congenital Heart Disease Registry (JACPHR).

Background: Post-operative pulmonary hypertension (PH) following biventricular repair of congenital heart disease (CHD) remains a high-risk condition, but its prognosis and risk stratification are poorly defined. This study aimed to identify prognostic factors and develop a simple clinical risk score. Methods: Patients with post-operative PH enrolled in the Japan CHD-Pulmonary Hypertension Registry (2021-2024) were analyzed. Continuous and categorical variables were assessed by log-rank testing, and a composite risk score was developed to predict cardiovascular events. Prognostic performance was evaluated by Kaplan-Meier and Cox regression analyses. Results: Among 84 patients (median age 11.6 years; 55% men), eight cardiovascular events occurred during a mean follow-up of 18.2 months: three all-cause deaths, three hospitalizations for heart failure, and two cases of worsening functional class. Mean pulmonary artery pressure ≥30 mmHg, pulmonary vascular resistance index ≥4.0 WU·m Conclusions: This nationwide, registry-based study provides new insights into prognostic determinants and risk stratification in patients with post-operative PH. This study identified practical prognostic factors and proposed a simple, exploratory equal-weighted risk score. Prognostic significance was evident even at thresholds below conventional criteria, highlighting the vulnerability of this population and supporting the score's potential clinical utility pending external validation.