Assessment of STS-TR score for transcatheter tricuspid valve interventions: an international multicenter study

Background Transcatheter tricuspid valve intervention (TTVI) is increasingly utilized for symptomatic severe tricuspid regurgitation (TR), particularly in high-risk surgical patients. The Society of Thoracic Surgeons Tricuspid Regurgitation (STS-TR) score, that was developed for prediction of 30-day mortality after tricuspid valve surgery. The purpose of the current study is to evaluate the performance of the STS-TR score in patients who underwent TTVI. Methods A six-center international cohort of 457 patients who underwent TTVI for symptomatic severe or greater TR between 2019-2024 were assessed using the STS-TR score. TTVI included tricuspid edge-to-edge repair (T-TEER) (n=243), tricuspid valve replacement (TTVR) (n=131), and transcatheter tricuspid annuloplasty (TTA) (n=83). The STS-TR 30-day all-cause mortality score was calculated for each patient and compared to observed mortality. The performance of the STS-TR score was assessed using calibration plots, the Hosmer-Lemeshow (H-L) test, and C-statistic. Subgroup analyses were performed based on TTVI procedure type. Results Mean age was 78.6 ± 8.7 years, and 54.7% were female. The mean predicted 30-day all-cause STS-TR mortality was 8.16% ± 7.2%, while the observed mortality was 2.63% (p < 0.001). Subgroup analyses revealed similar calibration patterns, Figure 1. Calibration plots demonstrated overestimation across all procedure types. The C-statistic for the STS-TR score was 0.68 (95% CI: 0.54 - 0.82) (Figure 2), indicating suboptimal discrimination Conclusions The STS-TR score for isolated TR significantly overestimates TTVI 30-day mortality across all procedure types, including transcatheter repair (T-TEER and TTA) and replacement (TTVR), and demonstrates suboptimal discrimination. This may be related to lower risk of TTVI procedures compared to surgery or disparate cohorts. Prospective dedicated TTVI-specific risk prediction models for transcatheter repair and replacement procedures are needed.