Validation of the TRI-SCORE in patients undergoing surgery for isolated tricuspid regurgitation

Introduction: Estimation of peri-procedural risk in patients with tricuspid regurgitation (TR) undergoing isolated tricuspid valve surgery (ITVS) is of paramount importance. The TRI-SCORE is a new surgical risk scale specifically developed for this purpose, which ranged from 0 to 12 points and included eight parameters: right-sided heart failure signs, daily dose of furosemide ≥125 mg, glomerular filtration rate <30 mL/min, elevated bilirubin (with a value of 2 points), age ≥70 years, New York Heart Association Class III-IV, left ventricular ejection fraction <60% and moderate/severe right ventricular dysfunction (with a value of 1 point). The objective of the study was to evaluate the performance of the TRI-SCORE in an independent cohort of patients undergoing ITVS.

Methods: A retrospective observational study was performed in four centres, including consecutive adult patients undergoing ITVS for TR between 2005 and 2022. The TRI-SCORE and the traditional risk scores used in cardiac surgery (Logistic EuroScore (Log-ES) and EuroScore-II (ES-II)) were applied for each patient, and discrimination and calibration of the three scores were evaluated in the entire cohort.

Results: A total of 252 patients were included. The mean age was 61.5±11.2 years, 164 (65.1%) patients were female, and TR mechanism was functional in 160 (63.5%) patients. The observed in-hospital mortality was 10.3%. The estimated mortality by the Log-ES, ES-II and TRI-SCORE was 8.7±7.3%, 4.7±5.3% and 11.0±16.6%, respectively. Patients with a TRI-SCORE ≤4 and >4 had an in-hospital mortality of 1.3% and 25.0%, p=0.001, respectively. The discriminatory capacity of the TRI-SCORE had a C-statistic of 0.87 (0.81-0.92), which was significantly higher than both the Log-ES (0.65 (0.54-0.75)) and ES-II (0.67 (0.58-0.79)), p=0.001 (for both comparisons).

Conclusion: This external validation of the TRI-SCORE demonstrated good performance to predict in-hospital mortality in patients undergoing ITVS, which was significantly better than the Log-ES and ES-II, which underestimated the observed mortality. These results support the widespread use of this score as a clinical tool.