Assessment of liver stiffness in patients with tricuspid regurgitation: relationship with disease severity

Abstract

OBJECTIVE: Tricuspid regurgitation (TR) is known to be associated with liver cirrhosis. However, the pathophysiological effect of TR, right ventricular systolic pressure (RVSP) and the right ventricular (RV) function on the liver remains uncertain. The aim of this study was to evaluate the association between TR severity and the stiffness of liver. METHODS: A total of 105 patients with various degrees of (mild to severe) TR secondary to left heart disease were enrolled. Patients were divided into two groups based on their TR severity: 40 patients with mild-moderate TR (effective regurgitant orifice [ERO]<0.4cm2) and 65 patients with severe TR (ERO≥0.4cm2). Detailed transthoracic echocardiography was performed in all subjects. LV ejection fraction (LVEF), RVSP and RV systolic function assessed by tricuspid annular plane systolic excursion (TAPSE) were measured. Fibroscan transient elastography was used to estimate the level of liver stiffness and the threshold of significant fibrosis was defined as 7.5kPa. RESULTS: There was no significant difference in age, gender and LVEF between patients with mild-moderate and severe TR. Compared to patients with mild-moderate TR, patients with severe TR had higher RVSP (50.17±14.48 vs. 41.98±11.93mmHg, p=0.003), lower TAPSE (1.62±0.38 vs. 1.78±0.40cm, p=0.042), and higher value of liver stiffness (20.83±14.46 vs. 9.14±7.02Kpa, p<0.001). Liver fibrosis was found in 16 (40%) patients with mild-moderated TR and 59 (90.8%) patients with severe TR. ERO was significantly correlated with liver stiffness (B=10.81, 95% confidence interval [CI] 9.32 to 12.31, p<0.001). In multivariate analysis, adjusting for age, TAPSE, LVEF and RVSP, ERO remained independently predictive of liver fibrosis (B=10.39, 95%CI 8.77 to 12.00, p<0.001). CONCLUSIONS: Patients with TR have increased liver stiffness measured by fibroscan and was related closely with the severity of the TR. ERO remained an independent predictor of liver fibrosis in these patients after multivariable adjustment.