Reduced left ventricular elastance as a novel marker of cardiac dysfunction in patients with severe liver disease

Abstract

Abstract Introduction Left ventricular (LV) elastance reflects the contractility of the myocardium and is an index of cardiac performance. Liver cirrhosis is characterized by reduced systemic vascular resistance, leading to reduced afterload on the LV. This, combined with increased blood volume, results in increased preload, increased stroke volume and remodeling of the LV. The latter may result to alterations in end-systolic LV elastance (Ees) a parameter that has not been extensively studied in cirrhotics. Purpose To investigate the relationship between Ees and the severity of liver cirrhosis. Methods We conducted a cross-sectional study in which transthoracic echocardiography was performed in 75 patients with liver cirrhosis (mean age 58.9±8.5 years, 74.7% males). A verified noninvasive single-beat formula was used to calculate Ees. Specifically, Ees was calculated employing systolic and diastolic blood pressures, echo-derived stroke volume (SV), ejection fraction (LVEF) and the estimated normalized ventricular elastance at arterial end-diastole (ENd). The ENd was estimated from a group-averaged value adjusted for individual contractile/loading effects. The Model for End-Stage Liver Disease-Sodium (MELDNa) score, a widely used tool for assessing liver disease severity was also calculated. We compared Ees between patients with MELDNa scores above and below 15, which is the cutoff commonly used to indicate severe liver disease. Results Mean Ees in the cohort of the 75 patients was 2.34±0.81mmHg/ml. Ees was correlated with end-systolic LV volume (rho=-0.448, p<0.001), SV (rho=-0.568, p<0.001) and systolic blood pressure (rho=0.283, p=0.014), but not with LVEF. Mean MELDNa score was 15.5±7.3 and 32 (42.7%) of patients had MELDNa score ≥ 15. Mean Ees in patients with MELDNa score above 15 was significantly lower than in patients with MELDNa score below 15 (2.08±0.61mmHg/ml vs 2.54±0.89mmHg/ml, p=0.015). The association remained significant in a multivariate model after adjusting for age, sex, and body surface area (B=-0.426, p=0.015). Conclusion Our study demonstrates that patients with severe liver disease have lower Ees, indicating impaired LV function. Ees could be a useful marker for identifying patients with liver cirrhosis who are at increased risk of cardiovascular complications. Further research is needed to better understand the mechanisms underlying this association and to propose therapeutic interventions aimed at improving LV function in this special population.