Incremental Prognostic Value of Right Ventricular-Pulmonary Artery Coupling to a Clinical Risk Score in Tricuspid Regurgitation: The TRIO-RV Score.

Objectives: There are limited data evaluating the echocardiographic parameters of risk in tricuspid regurgitation (TR) patients. We sought to evaluate the incremental prognostic value of quantitative right ventricle (RV) function and RV-pulmonary artery (RV-PA) coupling to an established clinical risk score in TR patients.

Methods: We retrospectively identified patients with moderate or greater TR from January 1, 2019, to June 30, 2019. Univariable and multivariable Cox proportional hazards regressions were used to test the association of right ventricular free wall strain (RVFWS), RVFWS indexed to right ventricular systolic pressure (RVSP), and the Tricuspid Regurgitation Impact on Outcomes (TRIO) risk score with mortality. A novel TRIO-RV risk score was developed by incorporating RVFWS/RVSP into the clinical TRIO risk score.

Results: Among 417 patients, age 73 ± 11.5 years, 47% female, the TRIO score was 3.5 ± 2. The TRIO score was low risk in 213 (51%), intermediate risk in 162 (39%), and high risk in 42 (10%). During a median follow-up of 3.96 years (interquartile range, 1.66-4.34 years), death occurred in 157 patients (38%). The baseline TRIO risk category was associated with mortality (P < .001). After adjustment by TRIO risk score, both RVFWS <18.6% (adjusted hazard ratio, 3.08; 95% CI, 2.01-4.72; P < .001) and RVFWS/RVSP <0.43 %/mm Hg (adjusted hazard ratio, 2.76; 95% CI, 1.75-4.35, P < .001) remained significantly correlated with mortality. With the addition of RVFWS/RVSP, 151 (40%) patients with low- and intermediate-risk TRIO scores were reclassified to a higher-risk TRIO-RV score. The chi-square value increased in sequential models predictive of mortality for the TRIO score alone, the TRIO score plus RVFWS <18.6%, and the TRIO score plus RVFWS/RVSP <0.43 %/mm Hg (model chi-square 38.3, 72.2, and 82.3, respectively).

Conclusions: Quantitative parameters of RV function are associated with mortality in TR patients even after correction for an existing clinical risk score. Incorporating RVFWS/RVSP into the TRIO clinical risk score, the TRIO-RV score, reclassifies a substantial number of low- and intermediate-risk patients into higher-risk categories and improves risk stratification.