Heart Failure

Definition | Aetiology | Pathophysiology | Risk Factors | Signs and Symptoms | Investigations | Management | Patient Advice

Definition

Heart Failure is a clinical syndrome characterised by the heart's inability to pump blood effectively to meet the body's needs. This results in symptoms such as breathlessness, fatigue, and fluid retention.

Aetiology

Common causes include:

• Ischaemic Heart Disease: The most common cause, often due to previous myocardial infarction.
• Hypertension: Long-standing high blood pressure leading to left ventricular hypertrophy.
• Cardiomyopathies: E.g., dilated or hypertrophic cardiomyopathy.
• Valvular Heart Disease: Conditions such as aortic stenosis or mitral regurgitation.
• Arrhythmias: Persistent atrial fibrillation or ventricular arrhythmias.

Pathophysiology

Heart failure involves the following mechanisms:

• Decreased Cardiac Output: Impaired ability to pump blood effectively.
• Neurohormonal Activation: Activation of the renin-angiotensin-aldosterone system (RAAS) and sympathetic nervous system exacerbates fluid retention and vasoconstriction.
• Ventricular Remodeling: Structural changes in the heart lead to worsening function.

Risk Factors

Key risk factors include:

• Hypertension and ischaemic heart disease.
• Diabetes and obesity.
• Smoking and alcohol misuse.
• Family history of cardiomyopathies.
• Chronic kidney disease.

Signs and Symptoms

Heart failure presents with a variety of symptoms and signs:

• Dyspnoea: Breathlessness on exertion or at rest.
• Orthopnoea: Breathlessness when lying flat.
• Paroxysmal Nocturnal Dyspnoea: Sudden breathlessness during sleep.
• Peripheral Oedema: Swelling in the lower limbs.
• Fatigue: Persistent tiredness and reduced exercise tolerance.
• Elevated Jugular Venous Pressure (JVP):

Figure 1: Elevated JVP in a patient with heart failure.

Investigations

Key investigations include:

• Clinical Symptoms and Signs: Initial assessment includes recognising symptoms such as dyspnoea and fatigue.
• Blood Tests:
  • Brain Natriuretic Peptide (BNP):
    • BNP <100 ng/L: Heart failure unlikely.
    • BNP 100–400 ng/L: Referral to heart failure clinic within 6 weeks.
    • BNP >400 ng/L: Urgent referral within 2 weeks.
  • Renal Function and Electrolytes: Assess for kidney involvement and medication side effects.
• Chest X-ray: Key findings include cardiomegaly, pulmonary oedema, and Kerley B lines.
• Echocardiography: To assess ejection fraction and structural abnormalities.

Figure 2: Major signs and symptoms of heart failure.

Management

1. Acute Management

• Oxygen Therapy: For hypoxia.
• Diuretics: Furosemide or bumetanide to relieve fluid overload.
• Nitrates: For acute pulmonary oedema to reduce preload.

2. Chronic Management

• ACE Inhibitors: E.g., ramipril to reduce afterload and improve cardiac function.
• Beta-blockers: E.g., bisoprolol for rate control and neurohormonal modulation.
• Mineralocorticoid Receptor Antagonists: E.g., spironolactone for patients with reduced ejection fraction.
• SGLT2 Inhibitors: E.g., dapagliflozin for additional benefit in heart failure with reduced ejection fraction.

3. Specialist Referral

Referral to a heart failure clinic is essential for optimisation of medical therapy and monitoring.

Patient Advice

Key advice includes:

• Maintain a low-sodium diet and avoid excess fluid intake.
• Take prescribed medications consistently.
• Engage in regular light exercise as tolerated.
• Report worsening symptoms such as weight gain, increased dyspnoea, or swelling.

Figure 3: Pitting oedema in a patient with heart failure.

References

1. James Heilman, MD (2009). Elevated Jugular Venous Pressure [Image]. Available at: https://upload.wikimedia.org/wikipedia/commons/4/4d/Elevated_JVP.JPG (Accessed: 30 December 2024).
2. National Heart, Lung, and Blood Institute (2008). Signs and Symptoms of Heart Failure [Image]. Available at: https://upload.wikimedia.org/wikipedia/commons/9/99/Heartfailure.jpg (Accessed: 30 December 2024).
3. James Heilman, MD (2009). Pitting Oedema in Heart Failure [Image]. Available at: https://upload.wikimedia.org/wikipedia/commons/8/84/Combinpedal.jpg (Accessed: 30 December 2024).