Background: The fibrosis-4 (FIB-4) index is used to evaluate liver disease patients. It can also be used to evaluate the prognosis for heart disease patients; however, its ability to determine the prognosis of severe isolated tricuspid regurgitation (TR) patients is unclear. This study aimed to clarify the association between FIB-4 index scores and the cardiovascular prognosis for severe isolated TR patients.

Methods and Results: This was a dual-center, retrospective study. From 2011 to 2019, 111 consecutive outpatients with severe isolated TR (mean age, 68.6 years; 53.2% male) were evaluated. Major adverse cardiovascular events (MACEs) were defined as the composite of cardiovascular death, hospitalization for heart failure, myocardial infarction, and stroke. The association between FIB-4 index scores and echocardiography was also evaluated. During a median follow up of 3.0 years, 24 patients were lost to follow up and 40 MACEs occurred. Baseline FIB-4 index scores for patients with MACEs were significantly higher than those for patients without MACEs. A multivariate analysis revealed that FIB-4 index scores are significantly associated with MACEs (hazard ratio, 1.89; 95% confidence interval, 1.01–3.54; P=0.046). A linear regression analysis indicated that FIB-4 index scores were correlated with echocardiographic parameters, including the left atrial volume index and left ventricular end-diastolic diameter.

Conclusions: The FIB-4 index score may be a useful predictor of MACEs for patients with severe isolated TR.