Interplay between Heart Disease and Metabolic Steatosis: A Contemporary Perspective

Abstract

The liver-heart axis is a growing field of interest owing to rising evidence of complex bidirectional interplay between the two organs. Recent data suggest non-alcoholic fatty liver disease (NAFLD) has a significant, independent association with a wide spectrum of structural and functional cardiac diseases, and seems to worsen cardiovascular disease (CVD) prognosis. Conversely, the effect of cardiac disease on NAFLD is not well studied and data are mostly limited to cardiogenic liver disease. We believe it is important to further investigate the heart-liver relationship because of the tremendous global health and economic burden the two diseases pose, and the impact of such investigations on clinical decision making and management guidelines for both diseases. In this review, we summarize the current knowledge on NAFLD diagnosis, its systemic manifestations, and associations with CVD. More specifically, we review the pathophysiological mechanisms that govern the interplay between NAFLD and CVD and evaluate the relationship between different CVD treatments and NAFLD progression.

Keywords: atrial fibrillation; cardiovascular diseases; cardiovascular diseases prognosis; cardiovascular medications; fatty liver; ischemic heart disease; metabolic syndrome; non-alcoholic fatty liver disease; non-alcoholic fatty liver disease diagnosis; pathophysiology.

Figure 1

Summary of Mutual Exacerbation of Hepatic and Cardiac Disease Severity. Nonalcoholic fatty liver is associated with several cardiac diseases, including heart failure, cardiomyopathy, ischemic heart disease, and arrythmias. In contrast, there is a paucity of studies evaluating cardiac diseases leading to hepatic dysfunction.

Figure 2

Summary of suggested pathophysiological mechanisms underlying the cardio hepatic interactions in NAFLD, ischemic hepatitis and congestive hepatopathy with cardiovascular diseases. ADMA, asymmetric dimethyl arginine; CCL3, chemokine ligand 3; CO, cardiac output; CRP, C-reactive protein; EPCs, endothelial progenitor cells; HDL, high-density lipoproteins; HF, heart failure; HTN, hypertension; IL-1, interleukin 1; IL-6, interleukin 6; LDL, low-density lipoprotein; M1/M2, macrophage phenotype 1/2 ratio; NAFLD: non-alcoholic fatty liver disease; OxLDL oxidized low-density lipoprotein; sICAM, soluble intracellular adhesion molecule; TG, Triglycerides; TNF-α, tumor necrosis factor α; VLDL, very low-density lipoproteins.