Prognostic value of the liver fibrosis marker fibrosis-5 index in patients with severe isolated tricuspid regurgitation: comparison with fibrosis-4 index

The fibrosis-4 index (FIB4), a liver fibrosis maker, has been shown to be associated with the prognosis in patients with severe isolated tricuspid regurgitation (TR). Recent study showed that the fibrosis-5 index (FIB5), which was calculated by albumin, alkaline phosphatase, aspartate transaminase, alanine aminotransferase and platelet count, had better prognostic value than FIB4 in patients with heart failure. The aim of this study was to evaluate the usefulness of FIB5 index for predicting prognosis in patients with severe isolated TR and compare the prognostic value between the FIB4 and the FIB5 in those patients. This was a dual-center, retrospective study. 113 consecutive outpatients with severe isolated TR (mean age, 65.8 years; 47.8% male) were analyzed. Major adverse cardiovascular events (MACEs) were defined as the composite of cardiovascular death, hospitalization for heart failure, myocardial infarction, and stroke. During a median follow-up of 3.0 years, 41 MACEs occurred. Patients with MACEs had a lower the FIB5 than patients without MACEs. The multivariate Cox analysis revealed that the FIB5 < -4.30 was significantly associated with higher incidence of MACEs after adjusted by confounding factors. Receiver-operating characteristic curve analyses showed that prognostic values did not differ between the FIB5 and the FIB4 in whole patients and in patients aged ≥ 70 years; while, in patients aged < 70 years, the FIB5 had better prognostic value than the FIB4. The FIB5 may be a useful predictor of MACEs in patients with severe isolated TR.