- Heart failure is a complex clinical syndrome that occurs when the heart is unable to pump sufficient blood to meet the metabolic demands of the body or can do so only at elevated filling pressures. It represents the final common pathway of many cardiovascular diseases, including coronary artery disease, hypertension, cardiomyopathy, and valvular disorders. Rather than being a single disease, heart failure is a multifactorial condition characterized by impaired ventricular function, neurohormonal activation, and progressive structural remodeling of the heart. It is a leading cause of hospitalization and mortality worldwide, particularly in older adults.
- The condition is broadly classified into heart failure with reduced ejection fraction (HFrEF) and heart failure with preserved ejection fraction (HFpEF). In HFrEF, the heart’s pumping ability is weakened due to systolic dysfunction, most often from myocardial damage such as that caused by myocardial infarction or dilated cardiomyopathy. HFpEF, on the other hand, arises from diastolic dysfunction, where the ventricles become stiff and cannot relax properly, limiting their ability to fill with blood, even though systolic function is relatively preserved. A third category, heart failure with mildly reduced ejection fraction (HFmrEF), has also been recognized in recent years, representing an intermediate group with overlapping features.
- Pathophysiologically, heart failure involves maladaptive processes that perpetuate disease progression. Reduced cardiac output triggers activation of the renin–angiotensin–aldosterone system (RAAS) and the sympathetic nervous system, which initially help maintain perfusion but eventually contribute to fluid retention, vasoconstriction, hypertrophy, and fibrosis. Elevated levels of natriuretic peptides (BNP, NT-proBNP) reflect compensatory mechanisms attempting to counteract these effects. Persistent imbalance between neurohormonal systems leads to ventricular remodeling, worsening dysfunction, and clinical deterioration.
- Clinical manifestations of heart failure are diverse and can be insidious or acute. The cardinal symptoms include dyspnea, fatigue, exercise intolerance, and fluid retention. Left-sided failure typically presents with pulmonary congestion, orthopnea, and paroxysmal nocturnal dyspnea, while right-sided failure manifests as peripheral edema, hepatomegaly, ascites, and jugular venous distention. Advanced cases can lead to cachexia, renal dysfunction, and multi-organ failure. Symptoms often fluctuate, with periods of stability punctuated by episodes of acute decompensation requiring hospitalization.
- Diagnosis relies on a combination of history, physical examination, laboratory testing, and imaging. Measurement of natriuretic peptides provides valuable diagnostic and prognostic information. Echocardiography is the cornerstone imaging modality, used to assess ejection fraction, wall motion, chamber size, and valvular function. Additional tests such as ECG, chest X-ray, cardiac MRI, and invasive hemodynamic monitoring may be used in selected cases.
- Management of heart failure involves both lifestyle measures and pharmacological or device-based therapies. Lifestyle recommendations include sodium restriction, fluid management, exercise training, and avoidance of alcohol or smoking. For HFrEF, cornerstone therapies include ACE inhibitors (or ARNI: angiotensin receptor–neprilysin inhibitors), beta-blockers, mineralocorticoid receptor antagonists (MRAs), and sodium-glucose cotransporter-2 (SGLT2) inhibitors. Diuretics are used for symptomatic relief of fluid overload. In advanced cases, implantable cardioverter-defibrillators (ICDs), cardiac resynchronization therapy (CRT), and left ventricular assist devices (LVADs) may be indicated. Heart transplantation remains the ultimate option for selected patients with refractory disease. In contrast, treatment for HFpEF remains less well defined, focusing on symptom control, risk factor management (e.g., hypertension, atrial fibrillation, diabetes), and emerging therapies like SGLT2 inhibitors.
- From a public health perspective, heart failure is a major challenge due to its high prevalence, chronic course, and substantial healthcare costs. Despite advances in treatment, prognosis remains poor: five-year mortality rates rival those of many cancers. However, early detection, optimal guideline-directed therapy, and personalized approaches have significantly improved survival and quality of life in recent decades.
