Survival prospects of pulmonary arterial hypertension associated with congenital heart disease: Insights from the HOPE registry

Background: Pulmonary arterial hypertension (PAH) is a severe complication among adult patients with congenital heart disease (ACHD). This study presents real-world data on risk stratification, pharmacotherapy and survival rates in PAH-ACHD. Methods: Data from PAH-ACHD patients were analyzed using The Hellenic Pulmonary Hypertension Registry (HOPE), spanning eight specialized centers between 2015 and 2023. Patients were categorized into low, intermediate, and high-risk groups using the ESC/ERS three-strata model to assess 1-year mortality risk. Results: A total of 93 PAH-ACHD patients were included (median age 38.5 years, 60.2 % women). Most patients had an atrial septal defect (37.6 %) or a ventricular septal defect (35.5 %), with 11.8 % presenting with complex ACHD. Eisenmenger syndrome was present in 35.5 % of patients. The proportion of low-risk patients nearly doubled from first to last assessment (24.7 % vs. 40.9 %, p = 0.001). Initially, 52.7 % of patients were on PAH monotherapy, with a subsequent shift towards combination therapy (73.1 %) during follow-up. Over a median follow-up of 5.9 years, 29 patients (31.1 %) died, with 1- and 5-year survival rates of 95.5 % and 81.9 %, respectively. Compared to the high-risk group, low- and intermediate-risk patients exhibited a 70 % and 50 % lower hazard of death, respectively. The lowest survival rates were observed in patients with Eisenmenger physiology. Conclusion: Survival prospects were favorable for the non-high risk patients in this nationwide cohort of PAHACHD patients. The observed shift towards combination therapy use may have contributed to the improvement in 1-year ESC mortality risk, underscoring the importance of timely combination therapy with PAH drugs.