Heart Failure/Congestive Heart Failure

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Heart Failure/Congestive Heart Failure (CHF)

Common serious clinical syndrome due to an imbalance in the pump function of the heart failing to maintain the circulation of the blood adequately  fluid retention. Characterised by inadequate tissue perfusion and volume overload  syndrome of dyspnoea, fatigue and oedema. Common final state for many cardiovascular disorders.

Aetiology:
Usually a complication of other diseases – hypertension; ischaemic heart disease; valvular heart disease; arrhythmias; cardiomyopathy; congenital defects; pulmonary hypertension; connective tissue diseases; endocrine and metabolic disorders.

Pathophysiology:
Oedema – due to reduced renal blood flow  increase in circulating angiotensin II  retention of Na and water  oedema in lungs and lower limb

Classification:
1) High output failure (output is normal or increased when needs are increased – failure occurs when cardiac output fails to meet the need; due to anaemia, hyperthyroidism, Paget’s disease, arteriovenous malformation)
2) Low output failure (output of heart is not adequate to meet needs; due to excessive preload (eg mitral regurgitation, fluid overload), failure of heart pump (eg ischaemic heart disease, cardiomyopathy, constrictive pericarditis, beta-blockers, hypertension)
3) Left or right ventricular failure (if left  to pulmonary oedema; if right  peripheral oedema)

Clinical features:
Initially only apparent during exercise  later classical symptoms of oedema, breathlessness and lethargy occur during everyday activity.
Acute symptoms – tachycardia; dyspnoea; poor tolerance of exercise
Chronic symptoms – cardiac arrhythmia’s; hypertension and oedema

Lower limb implications:
• oedema  irritation and shoe fitting problems; higher risk of skin breakdown
• stasis dermatitis and ulcers

New York Heart Association Functional Classification :
• Class 1 – no limitations; ordinary physical activity does not cause undue fatigue, dyspnoea or palpitations
• Class 2 – slight limitation of physical activity; such patients are comfortable at rest; ordinary physical activity results in fatigue, palpitations, dyspnoea or angina
• Class 3 – marked limitation of physical activity; although patients are comfortable at rest, less than ordinary activity will lead to symptoms
• Class 4 – inability to carry on physical activity without discomfort; symptoms of congestive heart failure are present even at rest; with any physical activity, increased discomfort is experienced

Management:
Initial assessment – ECG to evaluate left ventricular function
Nonpharmacological:
• restricted salt intake; avoidance of excessive fluids; weight reduction if obese; limit alcohol intake
• exercise training (walking or cycling)

Pharmacological:
ACE inhibitors (dilate arteries and veins  reduces cardiac afterload  increase in stroke volume and cardiac output); diuretics if blood volume high (reduce blood volume  decrease venous pressure, afterload, peripheral oedema); beta blockers; cardiac glycoside

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