Impaired right ventricular strain is associated with worse prognosis in patients with liver cirrhosis

Abstract Introduction Cirrhotic cardiomyopathy is a complication of liver cirrhosis accounting for significant morbidity and associated with reduced patient survival. It is characterized by reduced afterload, increased cardiac output, and diastolic dysfunction. However, there are limited data regarding the prognostic significance of right ventricular (RV) mechanics. Novel echocardiographic techniques such as speckle tracking echocardiography can detect subclinical myocardial dysfunction early in the course of non-ischemic myocardiopathies. Purpose To investigate the prognostic role of RV free wall strain (RVFWS) in patients with liver cirrhosis. Methods We prospectively enrolled 70 patients with liver cirrhosis in stable clinical condition. Patients with coronary artery disease, valvular heart disease, ongoing alcohol consumption or poor acoustic window were excluded from the study. Transthoracic echocardiography was performed and RVFWS was calculated from RV focused 4-chamber views using a dedicated software. Since RVFWS was as expected negative in all patients, absolute values were used for all calculations. Clinical and laboratory examination was also performed in all patients and the Model for End-Stage Liver Disease (MELD) score a widely used tool for assessing liver disease severity was calculated. All-cause mortality at 24 months was the primary endpoint and was available in all patients. Results Mean RVFWS in the cohort was 27.4±6.3% and using a lower normal limit of 20%, reduced RVFWS was detected in six patients. According to the Spearman coefficient analysis, RVFWS was correlated with MELD (rho=0.274, p=0.023) indicating increased values in patients with more advanced liver disease. According to the univariate Cox-regression proportion hazard models RVFWS as a continuous variable was not significantly correlated with worse two year survival (HR: 1.01 (0.95-1.08, p=0.658). Interestingly, among conventional echocardiographic parameters basal RV diameter (p=0.004) and right atrial end-systolic area (p=0.008) were associated with increased risk for the primary endpoint. The association of the primary endpoint with other parameters of RV systolic function was also not statistically significant. The Multivatiate Cox Regression survival analysis, which incorporated age, sex, MELD, hemoglobin, systolic blood pressure and cardiac output, showed that among echocardiographic parameters for the evaluation of the RV, only RVFWS showed a tendency to be associated with worse survival (p=0.062). When patients were stratified into tertiles according to RVFWS values, those in the first tertile (with lower absolute RVFWS values) had significantly increased hazard for the primary endpoint (HR: 5.82, 2.18-15.8, P<0.001) (figure 1). Conclusions RVFWS values are within normal limits in most patients with liver cirrhosis. When adjusted for the severity of the liver disease, reduced RVFWS values are associated with worse prognosis in cirrhotics.