However, the major effect of β-AR blockage in the heart is the suppression of lipolysis, decreased fatty acid uptake, and a reduction in myocardial fatty acid oxidation which may result in a compensatory increase in glucose oxidation and its resulting metabolic benefit in treating HF [362,363,364,365,366,367,368] (Figure 2). This evidence concerns the gene ADRB2 and hydrops fetalis.