Longitudinal changes in right ventricular-pulmonary arterial coupling after defect closure in adult congenital heart disease: The LET SHINE registry

Background: Right ventricular-pulmonary arterial (RV-PA) coupling reflects right ventricular adaptation to afterload and can be estimated non-invasively by echocardiography. Whether coupling recovery after defect closure in adult left-to-right shunt congenital heart disease (CHD) differs by lesion location, and whether baseline coupling predicts persistent pulmonary hypertension (PH), remains poorly defined in Southeast Asian populations. Objective: To evaluate longitudinal change in echocardiographic RV-PA coupling after defect closure, compare trajectories between pre-tricuspid (atrial septal defect) and post-tricuspid (ventricular septal defect and patent ductus arteriosus) lesions, and assess baseline coupling as a predictor of persistent PH at 12 months. Methods: This retrospective cohort study included 93 adults with left-to-right shunt CHD from the LET SHINE Registry who underwent defect closure and echocardiography at baseline (T0), 3 months (T1), and 12 months (T2), right heart catheterization is performed before the defect was closed. Six RV-PA coupling ratios (TAPSE/sPAP, TAPSE/PVAcT, TAPSE/TRV max, FAC/sPAP, FAC/PVAcT, FAC/TRV max) were compared across time, between lesion groups (Linear Mixed Model), and by ROC analysis for persistent PH (echocardiographic sPAP ≥35 mmHg at T2). Result: All six ratios improved significantly from T0 to T1 (p<0.001) and remained stable to T2. Pre-tricuspid lesions had lower baseline coupling but greater, more sustained improvement (group×time interaction p<0.001 for all ratios). Persistent PH occurred in 23/93 patients (24.7%). Baseline TAPSE/sPAP and FAC/sPAP discriminated persistent PH (AUC 0.780 and 0.786) comparably to invasive mPAP and PVR (AUC 0.805 and 0.800). Conclusion: RV-PA coupling improves substantially within 3 months after defect closure (all ratios, p<0,001), reflecting an acute fall in RV loading once the shunt is closed rather than slow structural remodelling, but follows a lesion-specific trajectory (group×time interaction p≤0,012; greater 12-month gains in pre-tricuspid than post-tricuspid lesions, Cohen's d 0,53-0,77), consistent with the differing reversibility of volume-overload (ASD) versus combined volume-pressure overload (VSD/PDA) remodelling. Baseline coupling ratios offer non-invasive predictive value for persistent PH (TAPSE/sPAP and FAC/sPAP AUC 0,780 dan 0,786) comparable to invasive hemodynamics (mPAP and PVR AUC 0,805 dan 0,800), because these ratios capture RV function relative to its afterload rather than contractility alone.