Echocardiographic Assessment of RV–PA Coupling in Advanced Heart Failure: A Comparative Analysis of Volumetric and Strain‐Based Measures
Seda Tanyeri, Murat Karaçam, Barkın Kültürsay, Azmican Kaya, Deniz Mutlu, Süleyman Çağan Efe, Gülümser Sevgin Halil, Özgür Yaşar Akbal, Cem Doğan, Mehmet Kaan Kırali, Rezzan Deniz Acar
Abstract
BACKGROUND: Right ventricular (RV) dysfunction is a key determinant of prognosis in advanced heart failure (HF) patients, particularly those undergoing heart transplantation. Noninvasive RV-pulmonary arterial (PA) coupling indices, such as tricuspid annular plane systolic excursion (TAPSE)/pulmonary artery systolic pressure (PASP), fractional area change (FAC)/PASP and strain-based parameters, offer potential in predicting clinical outcomes. However, their comparative prognostic value remains unclear. METHODS: A retrospective cohort of 247 patients evaluated for heart transplantation between 2021 and 2023 was included. Echocardiographic parameters, including TAPSE (mm), FAC (%), RV ejection fraction (RVEF, %), lateral tricuspid annular systolic velocity (s' by tissue Doppler imaging, cm/s), RV free-wall strain (RVFWS, %), and global longitudinal strain (RVGLS, %) and PASP (mmHg), were measured. The primary composite outcome was heart transplantation, LV assist device implantation, or all-cause mortality. Cox regression (hazard ratios per 1-standard deviation [SD] change; for strain, per 1-SD decrease in absolute magnitude) and time-dependent receiver operating characteristic (ROC) analyses were performed to assess the prognostic value of RV-PA coupling indices. RESULTS: During a median follow-up of 452 days, 62 patients (25.1%) experienced the primary outcome. Patients with adverse outcomes had significantly lower TAPSE, FAC, s' (TDI), and higher PASP. RV-PA coupling indices, including TAPSE/PASP, FAC/PASP, and RVGLS/PASP, were significantly lower in these patients. Among those parameters, RVEF/PASP and TAPSE/PASP showed numerically higher prognostic performance with C-index values of 0.827 and 0.826, respectively, while RV strain indices appeared to demonstrate relatively stronger prognostic capacity during longer follow-ups. CONCLUSION: Noninvasive RV-PA coupling indices, particularly TAPSE/PASP, FAC/PASP, and RVEF/PASP, were associated with adverse outcomes in advanced HF patients and may provide useful information for early risk stratification. Strain-based indices, especially RVFWS/PASP, appeared to offer additional prognostic value during longer-term follow-up. These findings highlight the potential clinical relevance of RV-PA coupling; however, they should be regarded as descriptive and hypothesis-generating until validated in larger, prospective cohorts.