The effect of chronic kidney disease on the association of tricuspid regurgitation with overall survival: Insights from SHEBAHEART big data

Background: Chronic kidney disease (CKD) is a common comorbidity among patients with tricuspid regurgitation, yet its impact on tricuspid regurgitation outcomes is underexplored. This study examines how CKD affects the relationship between severe tricuspid regurgitation and overall survival. Methods: This is a retrospective cohort study of all adult patients (> 18 years old) evaluated at the Sheba Medical Center, between 2007 and 2022, who underwent transthoracic echocardiographic evaluation. It is based on the SHEBAHEART big data registry. Sheba Medical Center is the largest hospital in Israel with approximately 115,000 admissions per year. The echocardiographic reports together with the electronic medical records of all patients are the source for this study. Patients with missing creatinine data within one month of their echocardiography study, as well as those who underwent tricuspid regurgitation intervention, were excluded from the study. Patients were categorized into four groups, according to the presence and severity of tricuspid regurgitation and stratified by CKD stage. The primary outcome was all-cause mortality. Results: The study included 78,147 patients (median age 67, IQR 55–78), with 2989 (4%) having severe tricuspid regurgitation and 19,910 (25%) with an estimated glomerular filtration rate [eGFR] < 60 mL/min/1.73 m². Over a median 4-year follow-up, 28,112 patients (36%) died. Both tricuspid regurgitation severity and CKD stage were associated with increased mortality risk (log-rank p < 0.001 for both). Adjusted models showed that compared to the none/trivial group, patients with mild, moderate, and severe tricuspid regurgitation had a 6%, 12%, and 35% higher risk of death, respectively (p < 0.001 for all). The association of tricuspid regurgitation with poor survival was CKD-dependent, with increased mortality risk of 56% vs. 23% among patients with eGFR < 60 vs. eGFR ≥ 60 (p for interaction < 0.001). The interaction analysis was no longer significant when right ventricular function was incorporated into the multivariable model. Subanalysis, limited to patients with isolated tricuspid regurgitation, yielded consistent results. Conclusions: The association between severe tricuspid regurgitation and poor survival is stronger in advanced CKD patients and may be modulated through right ventricular function.