Key Facts

Heart failure occurs when the heart cannot pump sufficient blood to meet metabolic demands or can only do so at elevated filling pressures. It is classified by ejection fraction into HFrEF, HFmrEF, and HFpEF. Management is guided by ejection fraction and NYHA class.

Epidemiology

• Prevalence: 1-2% of UK adults; 900,000+ people affected
• Incidence increases with age; mean age at diagnosis 75 years
• Accounts for approximately 5% of all emergency hospital admissions
• 1-year mortality after first hospitalisation: 25-30%

Aetiology

• Coronary artery disease: most common cause in UK (60-70% of HFrEF)
• Hypertension: major contributor, particularly to HFpEF
• Valvular heart disease: aortic stenosis, mitral regurgitation
• Cardiomyopathy: dilated (idiopathic, alcohol, familial), hypertrophic, restrictive, peripartum
• Arrhythmia: tachycardia-induced cardiomyopathy, AF
• Other: congenital heart disease, myocarditis, infiltrative disease (amyloidosis, sarcoidosis)

Pathophysiology

• Reduced cardiac output triggers neurohormonal activation: RAAS activation, sympathetic nervous system activation, ADH secretion
• These compensatory mechanisms initially maintain perfusion but cause progressive fluid retention, vasoconstriction, and myocardial remodelling
• Chronic volume and pressure overload leads to progressive ventricular dilatation and fibrosis
• Evidence-based therapies (ACEi, beta-blockers, MRA, SGLT2i) counteract these maladaptive neurohormonal responses

Left Heart Failure

• Breathlessness on exertion (most common symptom)
• Orthopnoea (breathlessness lying flat)
• Paroxysmal nocturnal dyspnoea (PND)
• Fatigue
• Bibasal crepitations on auscultation
• Third heart sound (S3 gallop)
• Tachycardia

Right Heart Failure

• Peripheral oedema (ankle swelling)
• Raised JVP
• Hepatomegaly and hepatojugular reflux
• Ascites (in severe cases)

NYHA Classification

• Class I: no limitation of physical activity
• Class II: slight limitation; comfortable at rest, symptoms with ordinary activity
• Class III: marked limitation; comfortable only at rest
• Class IV: symptoms at rest; unable to carry out any physical activity

Red Flags

• Acute pulmonary oedema: severe dyspnoea at rest, pink frothy sputum, hypoxia
• Cardiogenic shock: hypotension, cold peripheries, oliguria
• New-onset AF with rapid ventricular rate and decompensation
• Syncope in heart failure (consider arrhythmia, may need ICD assessment)

Bedside

• Observations: HR, BP, RR, SpO2, weight
• JVP assessment, auscultation (S3, murmurs, crepitations)
• Peripheral oedema assessment
• ECG: may show LVH, AF, Q waves, bundle branch block (normal ECG makes HFrEF unlikely)

Bloods

• NT-proBNP (or BNP): first-line diagnostic test in primary care
  • NT-proBNP <400 pg/mL: HF unlikely
  • NT-proBNP 400-2000 pg/mL: refer for echocardiogram within 6 weeks
  • NT-proBNP >2000 pg/mL: urgent referral within 2 weeks
• FBC: exclude anaemia
• U&Es: baseline renal function, electrolytes (before ACEi/MRA)
• LFTs: hepatic congestion
• TFTs: exclude thyroid disease
• HbA1c: diabetes screening
• Lipid profile

Imaging

• Echocardiogram: confirms diagnosis, classifies by EF, identifies structural abnormality
• CXR: cardiomegaly, pulmonary oedema, pleural effusions
• Cardiac MRI: gold standard for EF assessment; useful for cardiomyopathy, myocarditis, infiltrative disease

Special Tests

• Coronary angiography: if ischaemic aetiology suspected
• Iron studies: iron deficiency (ferritin <100 or ferritin 100-300 with transferrin saturation <20%) should prompt IV iron

Non-pharmacological

• Fluid restriction (1.5-2L/day in severe HF)
• Daily weight monitoring
• Low-sodium diet
• Cardiac rehabilitation and exercise programme
• Smoking cessation and alcohol moderation
• Annual influenza and pneumococcal vaccination
• Self-management plan with action plan for deterioration

Pharmacological (HFrEF — the 'four pillars')

1. ACE inhibitor:

• Ramipril: start 1.25mg OD, titrate to 10mg OD
• Enalapril: start 2.5mg BD, titrate to 20mg BD
• If intolerant (cough): switch to ARB (candesartan 4-32mg OD or valsartan 40-160mg BD)

2. Beta-blocker:

• Bisoprolol: start 1.25mg OD, titrate to 10mg OD
• Carvedilol: start 3.125mg BD, titrate to 25-50mg BD
• Nebivolol: start 1.25mg OD, titrate to 10mg OD (if age ≥70)

3. Mineralocorticoid receptor antagonist (MRA):

• Spironolactone 25-50mg OD (RALES trial: 30% mortality reduction)
• Eplerenone 25-50mg OD (EMPHASIS-HF trial; less gynaecomastia)

4. SGLT2 inhibitor:

• Dapagliflozin 10mg OD (DAPA-HF trial: 26% reduction in CV death/HF hospitalisation)
• Empagliflozin 10mg OD (EMPEROR-Reduced trial)
• Recommended regardless of diabetes status

Additional therapies:

• Sacubitril/valsartan (Entresto): start 24/26mg BD, titrate to 97/103mg BD — replaces ACEi/ARB if symptomatic despite optimal therapy (PARADIGM-HF: 20% mortality reduction vs enalapril)
• Ivabradine: 2.5-7.5mg BD if sinus rhythm HR ≥75 bpm despite maximally tolerated beta-blocker (SHIFT trial)
• Loop diuretics: furosemide 20-80mg OD for fluid overload (symptomatic, not mortality benefit)
• IV iron (ferric carboxymaltose): if ferritin <100 or ferritin 100-300 + TSAT <20% (IRONMAN, AFFIRM-AHF trials)
• Digoxin: for persistent symptoms or AF rate control
• Hydralazine + isosorbide dinitrate: if ACEi/ARB/ARNI not tolerated (A-HeFT trial; particularly beneficial in Black patients)

Devices

• ICD (implantable cardioverter-defibrillator): primary prevention if EF ≤35% despite ≥3 months optimal therapy (NYHA I-III)
• CRT (cardiac resynchronisation therapy): if EF ≤35%, QRS ≥150ms (LBBB), NYHA II-IV

Surgical

• Coronary revascularisation if ischaemic aetiology
• Valve repair/replacement for significant valvular disease
• Heart transplant: refractory HF in selected patients
• LVAD: bridge to transplant or destination therapy

Referral Criteria

• All patients with suspected HF: cardiology/HF specialist assessment after NT-proBNP
• Acute decompensation: hospital admission
• Consider palliative care referral for NYHA IV refractory symptoms

• 5-year mortality: approximately 50% for all-cause heart failure
• 1-year mortality: 25-30% after first HF hospitalisation
• HFrEF with optimal quadruple therapy: estimated survival benefit of 6-8 additional years compared to no treatment
• NYHA class IV: 1-year mortality >50%
• Each HF hospitalisation associated with progressive decline and increased subsequent mortality
• Heart transplant: 1-year survival 85-90%; 5-year survival 70-75%

Heart Failure Classification by Ejection Fraction

Landmark Heart Failure Trials