systolic heart failure

Systolic heart failure (heart failure with reduced ejection fraction, HFrEF) is characterized by impaired left ventricular contractility with ejection fraction (EF) ≤ 40% (moderate to severe systolic dysfunction). Causes include: (1) Ischemic cardiomyopathy (prior MI, chronic coronary disease)—most common cause in developed countries; (2) Idiopathic dilated cardiomyopathy (genetic, viral myocarditis, alcohol); (3) Pressure overload (hypertension, aortic stenosis) leading to concentric hypertrophy then eccentric dilatation; (4) Volume overload (regurgitant valves, anemia, renal failure); (5) Restrictive/infiltrative processes; (6) Toxic (alcohol, chemotherapy, cocaine); (7) Tachycardia-mediated cardiomyopathy. Pathophysiology involves neurohormonal activation: sympathetic overactivity, RAAS activation, and cytokine upregulation (TNF-alpha, IL-6). Initially compensatory but maladaptive long-term, leading to progressive remodeling (chamber enlargement, wall thinning). Presentation includes dyspnea (orthopnea, PND), fatigue, edema, and reduced exercise tolerance. Physical exam findings: rales, S3 gallop, elevated JVP, peripheral edema, cool extremities. Diagnosis: echocardiography shows reduced EF; BNP/NT-proBNP elevated. Management: ACE inhibitors/ARBs (reduce afterload and prevent remodeling), beta-blockers (reduce mortality), aldosterone antagonists, diuretics (symptom relief), and newer agents (SGLT2 inhibitors, ARNI). Acute decompensation treated with diuretics, vasodilators, and inotropes as needed.