Implications of Oxidative Stress in the Pathophysiological Pathways of Heart Failure

Heart failure (HF) is a major socioeconomic problem worldwide, associated with high morbidity and mortality due to several underlying diseases. HF is driven by several closely linked mechanisms whose effects are mutually reinforcing. Some of the signalling pathways involved in the progression of HF may initially be compensatory, such as the renin–angiotensin–aldosterone system (RAAS), whose hyperactivation plays a central role in the progression of HF by promoting fluid retention, inflammation, oxidative stress (OS), and myocardial dysfunction. Fluid retention is also promoted by the action of neprilysin, which contrasts natriuresis and vasodilation. Among the compensatory and subsequently maladaptive systems, chronic hyperactivation of the sympathetic nervous system (SNS) exacerbates maladaptive remodelling and drives the progression of HF. At the molecular level, mitochondrial dysfunction and inflammatory substances are involved in the development of a state of systemic oxidative stress and inflammation. The aim of the following manuscript was to revise the pathophysiology and role of OS in HF, focusing on the current knowledge of the molecular pathways involved.