Role of ACE Inhibitors and Angiotensin Receptor Blockers in Acute Heart Failure

Acute heart failure (AHF) is a critical medical condition characterized by sudden worsening of symptoms, requiring immediate treatment. Managing AHF is challenging due to the complexity of patient populations, insufficient understanding of pathogenesis, and limited evidence-based guidelines. The renin-angiotensin-aldosterone system (RAAS) plays a key role in heart failure pathophysiology, with its dysregulation leading to sodium retention, vasoconstriction, and adverse remodeling. RAAS inhibitors, such as ACE inhibitors and ARBs, have proven effective in reducing morbidity and mortality in heart failure with reduced ejection fraction (HFrEF), although their impact on heart failure with preserved ejection fraction (HFpEF) remains uncertain. Early initiation of these medications within 48 hours of hospital admission has shown improved outcomes in both HFrEF and HFpEF patients. Despite their benefits, ACE inhibitors and ARBs pose risks such as hypotension, hyperkalemia, and kidney dysfunction in AHF patients. This chapter discusses the clinical efficacy, safety, and evolving guidelines for ACE inhibitors and ARBs in treating AHF.