Messika-Zeitoun, D

Abstract Background While tricuspid regurgitation (TR) is predominantly functional, it can arise from various cardiac conditions. This study aimed to evaluate whether the benefits of tricuspid valve intervention, compared to conservative management, differ based on the underlying etiology. Methods In the TRIGISTRY international cohort, which includes consecutive patients with severe isolated functional TR across 33 centers in 10 countries, we compared mortality rates at 2 years between patients who underwent a tricuspid valve intervention (surgical or transcatheter) versus conservative management according to TR etiology. Patients were classified into three groups: (1) Isolated TR (ITR), defined as left ventricular ejection fraction (LVEF) >60%, systolic pulmonary artery pressure (sPAP) <50 mmHg, and no prior left-heart intervention (LHI); (2) LHI-TR, comprising patients with a history of LHI; and (3) Undetermined TR (UTR), which included those who did not meet the criteria for ITR or LHI, as well as those with missing sPAP data. Given previous findings indicating that intervention provided no survival benefit for patients with a high TRI-SCORE, the present analysis was restricted to individuals with low to intermediate TRI-SCORE (≤5). Survival outcomes between groups were compared using restricted mean survival time (RMST). Results A total of 1,552 patients (72±13 years; 56% female) with severe functional TR and a low (48%) or intermediate (52%) TRI-SCORE were included. Of these, 772 (50%) underwent an intervention, while 780 (50%) were conservatively managed. TR was classified as ITR in 201 patients (13%), LHI in 395 (25%), and UTR in 956 (62%). Overall, patients with ITR exhibited the lowest comorbidity burden, whereas those with UTR had the highest. After adjusting for comorbidities and TRI-SCORE, a survival benefit of a tricuspid valve intervention was observed in patients with ITR (survival estimate: 0.17, 95% CI [0.009, 0.32], P=0.039) and, to a lesser extent, in patients with UTR (survival estimate: 0.09, 95% CI [0.0, 0.184], P=0.048), but not in those with prior LHI (survival estimate: 0.06, 95% CI [-0.08, 0.2], P=0.4). Similar results were found when excluding patients with moderate or greater residual TR after intervention. Conclusion In TRIGISTRY, patients with ITR appeared to derive the greatest benefit from tricuspid valve intervention, followed to a lesser extent by those with UTR, while no benefit was observed in patients with prior LHI. However, the potential influence of unaccounted confounders cannot be excluded, and further studies are needed to better identify patients’ subsets that may derive the most benefit from a tricuspid valve intervention.