2D-Echocardiographic Estimation of Right Ventricular Volumes Using a Previously Validated Geometric Model Is Associated With Outcomes After Transcatheter Tricuspid Interventions

Aims: To determine whether a simplified, previously proposed two-dimensional (2D) approach to RV volume assessment can provide adjunctive prognostic information in patients undergoing Transcatheter Tricuspid Valve Interventions (TTVI). Methods and Results: In this prospective single-center study, 113 patients undergoing TTVI were included (T-TEER; n = 91, heterotopic caval valve implantation; n = 17, and orthotopic transcatheter tricuspid valve replacement; n = 5). RV end-diastolic and end-systolic volumes were calculated using a previously described 2D-based geometric model. The primary endpoint was a composite of all-cause mortality or rehospitalization for acute decompensated heart failure at 1 year. The primary endpoint occurred in 47 patients (41.6%). In univariable Cox regression analysis, both RVEDVi (HR 1.05 per 10 mL/m(2), 95% CI 1.01-1.10, p = 0.03) and RVESVi (HR 1.13 per 10 mL/m(2), 95% CI 1.01-1.25, p = 0.03) were associated with adverse outcome. Receiver operating characteristic analysis identified cut-off values of 90 mL/m(2) for RVEDVi and 35 mL/m(2) for RVESVi. Patients above these thresholds (diastolic, systolic, or both) showed significantly reduced event-free survival (log-rank p < 0.01). In a multivariable Cox regression analysis, RV dilatation showed a trend toward worse outcomes (HR 2.09, 95% CI 0.91-4.80, p = 0.08), whereas the TriScore remained independently associated with outcome (HR 1.30, 95% CI 1.10-1.53, p < 0.01). Conclusion: RV volumes derived from a simple 2D echocardiographic model are associated with clinical outcomes and may provide additional information for the assessment of patients undergoing TTVI.