A novel quantitative grading system to further characterize the prognosis of patients with functional tricuspid regurgitation

Abstract

Abstract Background Recent studies have suggested that current grading of tricuspid regurgitation (TR) has significant limitations and specifically cannot identify the various grades of severe TR (such as torrential). New cut-off values for the recommended measures of vena contracta (VC) width and effective regurgitant orifice area (EROA) have been proposed but not yet validated. Purpose To test the prognostic utility of new cut-offs for VC width and EROA in a large registry of patients with functional TR (FTR) and to integrate them into a novel comprehensive grading system. Methods FTR severity was evaluated in 1148 patients (mean age: 69±13 years, 50% male) with significant FTR (≥ moderate). Patients with congenital heart disease or who underwent tricuspid valve repair during follow-up were excluded. The primary endpoint was all-cause mortality. Based on Kaplan-Meier survival analyses, VC width significantly differentiated the prognosis of patients with moderate FTR vs severe FTR (with a cut-off value of 7 mm), whereas EROA was able to further stratify patients with more than severe (torrential) FTR. Therefore these two parameters were combined into a novel grading system (Figure: Upper Panel) to define: moderate FTR (VC <7 mm), severe FTR (VC ≥7 mm, EROA <80 mm2) and torrential FTR (VC ≥7 mm, EROA ≥80 mm2). Results According to our novel grading system a total of 146 patients (13%) showed moderate FTR, 547 patients (48%) had severe FTR and 454 patients (39%) presented with torrential FTR. Patients with torrential FTR had greater right ventricular (RV) dimensions, lower RV systolic function and were more likely to receive diuretics. The cumulative 10-year survival rates were significantly different among the groups: 54% for moderate FTR, 43% for severe FTR and 32% for torrential FTR (P=0.004 Figure – Lower Panel). After adjusting for potential confounders, torrential FTR retained its association with worse prognosis compared with other FTR grades (HR 1.28; 95% CI 1.07–1.54; P=0.007) together with age, coronary artery disease, diabetes, severe renal impairment, lower RV or left ventricular systolic function, higher pulmonary artery pressures, and dilated tricuspid annulus. Differently, severe FTR graded according to current guidelines did not show any association with the primary outcome (HR for severe FTR vs moderate FTR 1.17; 95% CI 0.96–1.42; P=0.128). Conclusion The proposed novel grading system combining measures of VC width and EROA is able to further risk stratify patients with FTR and specifically to identify patients with torrential FTR, a new clinical condition associated with even worse mortality than severe FTR. Figure 1 Funding Acknowledgement Type of funding source: None