Multimodality Assessment of Right Ventricular Function in Tricuspid Regurgitation and Its Impact on Outcomes in Patients undergoing Transcatheter Tricuspid Valve Interventions

Background Right ventricular (RV) adaptation to chronic volume and pressure overload is a key determinant of outcomes in severe tricuspid regurgitation (TR). Multi-slice cardiac computed tomography (MSCT) allows detailed assessment of RV morphology and function. RV–pulmonary artery (RV–PA) coupling, reflecting RV contractile performance relative to afterload, may provide prognostic information. Aim To evaluate TR-related changes in RV geometry, function, and RV–PA coupling using MSCT and invasive hemodynamics, and assess their predictive value for mortality after transcatheter tricuspid valve intervention (TTVI). Methods and Results In this multicenter retrospective study, 185 patients (mean age 78±7 years; 64% female) undergoing TTVI underwent full-cycle MSCT, echocardiography, and right heart catheterization. RV–PA coupling was calculated as MSCT-derived RV ejection fraction (RVEF) divided by invasively measured mean pulmonary artery pressure (mPAPinvasive). RV dilatation was associated with a geometric shift from triangular to cylindrical shape. RV–PA uncoupling (RVEF/mPAPinvasive <1.6, identified cut-off for 1-year mortality using Youden’s Index) was associated with higher RV sphericity and reduced RV and LV stroke volumes. Over a median follow-up of 316 days, 30 patients (16%) died. RV–PA uncoupling was associated with increased 1-year mortality (HR 6.4; 95% CI 2.7–14.8; P<0.001), even after adjustment for clinical baseline factors and residual TR after TTVI. Conclusion In severe TR, chronic volume overload may lead to adverse RV remodeling, impaired forward flow, and RV–PA uncoupling. The RVEF/mPAPinvasive ratio is a robust predictor of mortality after TTVI, supporting its use for risk stratification and clinical decision-making.