# Prevalence and Prognostic Value of Right Ventricular–Pulmonary Artery Uncoupling in Adults with Right-Sided Congenital Heart Disease

## TL;DR

This study shows that right ventricular-pulmonary artery uncoupling is a strong predictor of poor outcomes in adults with right-sided congenital heart disease.

## Contribution

The study establishes RV–PA uncoupling as a novel and robust independent prognostic marker in adults with R-CHD.

## Key findings

- RV–PA uncoupling was found in 36.4% of patients and strongly predicted adverse outcomes.
- RV–PA uncoupling outperformed individual components like TAPSE and PASP in predicting risks.
- RV–PA uncoupling and RV mid-diameter independently predicted the need for surgical or interventional procedures.

## Abstract

Background: Right-sided congenital heart diseases (R-CHDs) are frequently associated with right ventricular (RV) dysfunction and heterogeneous clinical trajectories, underscoring the need for individualized risk assessment. RV–pulmonary artery (RV–PA) coupling has emerged as an important prognostic marker in several cardiovascular conditions. However, its role in adults with R-CHD has not been well established. Methods: We retrospectively reviewed consecutive adults with R-CHD evaluated at our outpatient clinic between October 2013 and November 2023. RV–PA uncoupling was defined by echocardiography as a tricuspid annular plane systolic excursion (TAPSE) to pulmonary artery systolic pressure (PASP) ratio ≤0.55. The primary composite endpoint included all-cause mortality, major supraventricular and ventricular arrhythmias, unplanned cardiac hospitalizations, and need for (re)-interventions. Results: A total of 132 patients (mean age 41.6 ± 15.7 years; 51.5% male) were included. RV–PA uncoupling was identified in 48 patients (36.4%). Over a median follow-up of 40.3 months, the primary composite endpoint occurred in 71 patients (53.8%). Patients experiencing adverse outcomes were older and showed lower TAPSE, higher PASP, larger RV and right atrial dimensions, and a significantly higher prevalence of RV–PA uncoupling (p < 0.001). Multivariable Cox regression analysis demonstrated that RV–PA uncoupling was a strong independent predictor of adverse outcomes (HR 4.478, p < 0.001), outperforming its individual components. In addition, RV–PA uncoupling and RV mid-diameter independently predicted the need for surgical or interventional procedures during follow-up. Conclusions: RV–PA uncoupling provides robust and independent prognostic information in adults with R-CHD and represents a practical tool for personalized risk stratification, potentially guiding tailored surveillance strategies and timing of therapeutic interventions.