Congestive Heart Failure PDF

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Summary

Congestive Heart FailureCHF may be acute or chronic - Common complication of: o Chronic hypertension o Ischaemic heart disease o Heart valve disease o Chronic arrythmia (esp. Atrial Fibrillation)  Increased demands on the heart: Hyperthyroidism Severe anaemia  Acute onset of heart failure most com...

Description

Congestive Heart Failure

CHF may be acute or chronic •

Common complication of:



o Chronic hypertension o Ischaemic heart disease o Heart valve disease o Chronic arrythmia (esp. Atrial Fibrillation) Increased demands on the heart: Hyperthyroidism Severe anaemia



Acute onset of heart failure most commonly associated with myocardial infarction

Clinical manifestations: •

Dyspnoea (shortness of breath)

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Nocturnal cough

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Paroxysmal Nocturnal Dyspnoea (accumulation of fluid in lungs)

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Confusion

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Renal Failure } to brain & kidneys

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Oedema

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Reduced exercise tolerance, lethargy, fatigue (reduced cardiac output, impaired oxygenation)

} reduced blood flow

NYHA classification: •

Class I – asymptomatic = No symptoms on ordinary physical activity

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Class II – mild = Ordinary activity leads to symptoms

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Class III – moderate = Less than ordinary activity leads to symptoms

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Class IV – severe = Inability to carry out any activity without symptoms

Aims of treatment: •

Relief of symptoms

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Improved quality of life

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Slow deterioration in LV function

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Prevent admissions to hospital

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Prevent complications of disease

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Prolong survival

Heart failure management: To achieve improvement in symptoms: –

Diuretics

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Digoxin

–

ACE inhibitors

To achieve improvement in survival: –

ACE inhibitors

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β-blockers (eg. carvedilol and bisoprolol)

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Spironolactone

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Ivabradine

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Oral nitrates plus hydralazine

ACE inhibitors: •

Reduced mortality (typically by 30-40%)

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Delay disease progression

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Improvements in NYHA class

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Reduce hospital admissions

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Reduced need for diuretics

Contra-indications: Pregnancy Bilateral renal artery stenosis Aortic stenosis   BP Hyperkalaemia (serum K+ > 5.5mmol/L) Common side effects: –

Dry cough

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Hypotension

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Hyperkalaemia

Angiotensin II antagonists: Reserve for patients unable to tolerate ACE inhibitor –

Do not inhibit the breakdown of bradykinin so unlikely to cause persistent dry cough

Examples: candesartan, valsartan An alternative method of blocking RAAS system Monitoring in line with recommendations for ACE inhibitors

Beta blockers: •

Consider for patients with chronic stable heart failure resulting from LV dysfunction (NYHA class I-III)

•

Carvedilol, bisoprolol and nebivolol are currently licensed for heart failure in the UK

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Traditionally contraindicated in CHF

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More recent trials have shown benefits in mortality, reductions in hospital admissions, and symptom control

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Should be used in addition to diuretics and ACE inhibitors

Contraindications: Asthma Bradycardia Acute heart failure

Doses: LOW, titrated up every 1-2 weeks Introduce beta-blockers in a 'start low, go slow' manner. Assess heart rate and clinical status after each titration. Measure blood pressure before and after each dose increment of a beta-blocker

Diuretics: •

Consider for patients with signs and symptoms of water retention (eg. peripheral oedema, pulmonary oedema)

•

Examples: Furosemide, bumetanide, metolazone

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Remove excess fluid =  oedema and pulmonary congestion

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Improve symptoms and exercise tolerance

Side-effects: Dehydration

Hypotension

Electrolyte imbalance (Esp K+) Patients should be monitored regularly for renal failure and electrolyte imbalances, especially if they are also taking ACE inhibitors

Mineralocorticoid receptor antagonists: Consider in patients with moderate to severe heart failure (NYHA class III-IV) who are symptomatic despite taking ACE inhibitors and beta-blockers •

Examples: Eplerenone, sprironolactone

Improves symptom control

Reduce hospital admissions Reduce mortality •

Contraindications: Pregnancy   Na+

•

Severe renal failure   K+

Side-effects: Hyperkalaemia (esp. with ACE inhibitor)

Measure serum sodium and potassium, and assess renal function, before and after starting an MRA and after each dose increment.

Ivabradine: •

NYHA II-IV (mild- to-severe) class, in combination with beta-blocker or as alternative if beta-blocker not tolerated

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NOT administer if heart rate below 75bpm, unstable or acute heart failure

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Dose: 5mg twice daily initially, increased if necessary after two weeks to 7.5mg twice daily

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Side-effects: Bradycardia, headache, visual disturbance

Digoxin: •

Consider for patients with CHF 2o to AF

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More controversial in absence of AF

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Positive inotropic agent

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Improved symptom control

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Reduced hospital admissions = but, no change in mortality

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Contraindications Severe heart block Wolff–Parkinson-White syndrome (arrythmias)

•

Side-effects: (usually associated with excessive dosage) Arrythmias Nausea

Anorexia Vomiting

Confusion

Other treatment options: NITRATES plus HYDRALAZINE Typical place in therapy:    

ACE inhibitors (and ACE II inhibitors) are C/I (eg severe renal impairment) ACE inhibitor side-effects Patient has other conditions eg angina (nitrate only) Symptoms persist despite first-line treatment

Vasodilators: •

Survival benefits plus modest exercise capacity improvement (but less than ACE inhibitors)

•

Side effects (more common than ACE inhibitors): –

Postural hypotension (30% of patients) which may limit tolerability

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Dizziness and headaches

Drugs to avoid in CHF: • Class I antiarrthmnic drugs eg, lidocaine, flecainide • NSAIDs eg, ibuprofen, diclofenac • Negative inotropic calcium channel blockers = eg. diltiazem, verapamil

Non-drug management: • Stop smoking • Weight reduction &/or low fat diet • Regular physical exercise • Limited alcohol consumption • Reduced salt intake

Role of the pharmacist: • Promoting evidence-based prescribing • Advising on choice of agent • Optimising doses • Simplification of regimens • Monitoring efficacy • Highlighting adverse effects • Patient counselling...