Derangements in adrenergic-adipokine signalling establish a neurohormonal basis for obesity-related heart failure with a preserved ejection fraction

Among patients with heart failure and a preserved ejection (HFpEF), obesity is associated with a distinct phenotype that is characterized by adiposity-driven plasma volume expansion and cardiac overfilling, which is coupled with an impairment of ventricular distensibility. These pathophysiological abnormalities may be related to the increased actions of specific adipocyte-derived signalling molecules (aldosterone, neprilysin and leptin) that work in concert with increased renal sympathetic nerve traffic and activated beta2-adrenergic receptors to promote sodium retention, microvascular rarefaction, cardiac fibrosis and systemic inflammation. This interplay leads to striking activation of the mineralocorticoid receptor, possibly explaining why obese patients with heart failure are most likely to benefit from spironolactone and eplerenone in large-scale clinical trials. Additionally, adipocytes express and release neprilysin, which (by degrading endogenous natriuretic peptides) can further promote plasma volume expansion and cardiac fibrosis. Heightened neprilysin activity may explain the low circulating levels of natriuretic peptides in obesity, the accelerated breakdown of natriuretic peptides in HFpEF, and the cardiac decompression following neprilysin inhibition in HFpEF patients who are obese. Furthermore, as adipose tissue accumulates and becomes dysfunctional, its secretion of leptin promotes renal sodium retention, microvascular changes and fibrotic processes in the heart, and systemic inflammation; these effects may be mediated or potentiated by the activation of beta2-adrenergic receptors. These adrenergic-adipokine interactions provide a mechanistic framework for novel therapeutic strategies to alleviate the pathophysiological abnormalities of obesity-related HFpEF. Ongoing trials are well-positioned to test this hypothesis.