clinical knowledge summaries cks heart failure - chronic diagnosis and initial management in primary...

Clinical Knowledge Summaries CKS

Heart failure - chronic

Diagnosis and initial management in primary care.

Educational slides based on the CKS topic; Heart failure - chronic (Nov 2010), and NICE guidance (2010); Management of chronic heart failure in adults in primary and secondary care.

Key learning points and objectives

• To be able to:o Recognise people with suspected heart failure

(HF).o Outline how to investigate suspected HF.o Describe why natriuretic peptides are measured

and how they are used to decide on the urgency of referral.

o Explain why referral to a specialist is required.

Based on the CKS topic; Heart failure - chronic (Nov 2010), and NICE guidance (2010); Management of chronic heart failure in adults in primary and secondary care.

Definition• Heart failure (HF) - the ability of the heart to

maintain the circulation of blood is impaired.• HF with left ventricular systolic dysfunction.

o Evidence of left ventricular systolic dysfunction (e.g. reduced left ventricular ejection fraction [LVEF] on echocardiography [echo]).

o Accounts for a little more than half of the people with HF.

• HF with preserved ejection fraction (PEF).o Good contraction of the heart muscle on echo.o An LVEF of 45–50% or more is normal. o The usual cut off for PEF is 40-50% LVEF.


Causes• Conditions that damage heart muscle or limit its

ability to function normally e.g. o Coronary artery disease (most common).o Hypertension (next most common).o Cardiomyopathies.

• Conditions that reduce cardiac output e.g. o Increased vascular resistance with hypertension.o Abnormal heart rhythm

• Conditions that result in a high cardiac output e.g.o Anaemia.o Thyrotoxicosis.o Septicaemia.


How common is it? • Prevalence increases with age.

o 7% for people 75–84 years of age.o 20% for people 85 years of age or older.

• Accounts for:o 2% of all hospitalised bed-days.o 5% of all medical emergency admissions.

• Average GP will:o Look after 30 people with HF at any one time. o Suspect a new diagnosis of HF in 10 people annually.


New York Heart Association (NYHA) HF classification• Class I: asymptomatic left ventricular dysfunction is included:

o No limitations. Ordinary physical activity does not cause fatigue, breathlessness, or palpitation.

• Class II: symptomatically “mild”.o Slight limitation of physical activity. Such people are comfortable at rest.

Ordinary physical activity results in fatigue, palpitation, breathlessness, or angina pectoris.

• Class III: symptomatically “moderate”.o Marked limitation of physical activity. Although people are comfortable at rest,

less than ordinary physical activity will lead to symptoms.

• Class IV: symptomatically “severe”.o Inability to carry on physical activity with out discomfort. Symptoms of cardiac

failure are present even at rest.


Complications • Arrhythmias – common at any stage.

o Atrial fibrillation — prevalence increases with severity of HF. o Ventricular arrhythmias — common with dilated left ventricle and

reduced LVEF.

• Depressiono Occurs in up to one third of people with HF.

• Sexual dysfunctiono Common – may be caused by HF or drugs (e.g. beta-blockers).

• Cachexia (wasting) – serious complicationo Usually occurs together with severe dyspnoea and weakness.o Life expectancy is worse for people with cachexia and HF than that for

most cancers.

• Sudden death – about half of HF deaths are related to sudden cardiac death.


Prognosis• Prognosis depends on the cause, age,

comorbidities, and adherence to treatment. • But, in general, the prognosis is poor:

o 50% of people die within 4 years of diagnosis. o 40% of people admitted to hospital die or are

readmitted within 1 year.o Younger people and people with no other medical

problems do better.


Prognosis

• Mortality rates are beginning to drop.• Drug treatments and input from heart failure

specialists have reduced mortality and morbidity, but

• Prognosis is consistently poor for people who receive suboptimal care.


Cost of HF to the NHS• Total annual cost of HF is around 2% of the total

NHS budget: o 70% of this is due to the costs of hospitalisation.

• Admissions are usually protracted (7-8 days). • Readmissions are common:

o 1 in 4 patients are readmitted in three months. • Co-morbidities account for a substantial proportion

of admissions.• The costs increase with disease severity.


Suspecting HF • Suspect HF if there are symptoms, signs, or risk factors for

HF.• Symptoms include:

o Breathlessness (on exertion, lying flat, or on waking).o Fatigue.

o Fluid retention (ankle swelling, abdominal swelling). • Signs include:

o Laterally displaced apex beat.o Raised jugular venous pressure.o Enlarged liver (due to engorgement).o Third or fourth heart sound (gallop rhythm).o Tachycardia.o Lung crepitations (persisting after coughing).o Dependent oedema (legs, sacrum).


Suspecting HF• Risk factors for HF include:

o Myocardial infarction, coronary artery disease, or angina.o Atrial fibrillation.o Diabetes mellitus.o Hypertension.o Excessive alcohol consumption.o Previous cardiotoxic chemotherapy (e.g. doxorubicin,

daunorubicin).o Family history of heart failure or sudden cardiac death

from cardiomyopathy at a young age.


Differential diagnosis• Conditions causing shortness of breath such as:

o Chronic obstructive pulmonary disease.o Asthma.o Obesity.o Volume overload from renal failure or nephrotic syndrome.o Angina.o Anxiety.

• Conditions causing peripheral oedema such as: o Dependent oedema that is not pathological, (e.g. prolonged

inactivity).o Nephrotic syndrome.o Drugs (e.g. calcium-channel blockers, NSAIDs).o Hypoalbuminaemia.o Venous insufficiency.


How to investigate?

• Measure natriuretic peptides:o B-type natriuretic peptide (BNP)

• Secreted from the heart wall especially when stretched or when the pressure within it increases.

• Increases renal excretion of sodium and water.• Relaxes vascular smooth muscle, which leads to

vasodilation.o N-terminal pro-BNP (NT-proBNP)

• Inactive prohormone of BNP.


Why use natriuretic peptides?

• Natriuretic peptides help to determine:o The likelihood of the presence of heart failure.o The need for referral for specialist assessment and

confirmation of the diagnosis by echocardiography.

o The urgency of the referral.


Why use natriuretic peptides?• Good evidence that *:oElevated levels do not confirm the

diagnosis of heart failure, butoNormal levels rule the diagnosis out.oThe accuracy of both tests (BNP and

NT-proBNP) are similar.oBNP has a greater diagnostic accuracy

than ECG.* Based on a Health Technology Appraisal Mant, J. (2009) Systematic review and individual patient data meta-analysis of diagnosis of heart failure, with modelling of implications of different diagnostic strategies in primary care. 13(32), 1-207

How to investigate• If no previous MI:

o Measure the natriuretic peptide level, using either• B-type natriuretic peptide (BNP), or • N-terminal pro-BNP.

• If previous MI:o Do not measure the natriuretic peptide level.o Refer (within 2 weeks) for specialist assessment and

echocardiography.o If HF is suspect the prognosis is poor.

• For everyone (regardless of MI status) also do 12-lead electrocardiography.


How to investigate

• Look for aggravating factors and exclude other conditions using:o Chest X-ray.o Blood tests; U & Es, creatinine, FBC, thyroid function,

LFTs, glucose, lipids, and urinalysis.o Lung function tests (peak flow or spirometry).


If natriuretic peptides not measured• Where it is not possible to measure

natriuretic peptides:o Use an ECG to decide if referral is required.

• A normal ECG can help rule out HF, but o The presence of any abnormality does not help to

rule in the diagnosis of heart failure.o About 1 in 10 people with HF have a normal ECG.


Initial management• NICE recommends referral for specialist

assessment and echo to confirm the diagnosis as:o The diagnosis should not be based on the results

of echocardiography alone.o It is important to identify the type and severity of

the abnormality responsible for heart failure. • While awaiting confirmation of the diagnosis:

o Consider stopping any drugs that may affect the person’s heart failure (e.g. NSAIDs or calcium channel blockers).


Role of echocardiography • Excludes valve disease. • Assesses systolic and diastolic function.• Detects intracardiac shunts.• Measures ventricular function - (e.g. LVEF).

o An LVEF of 45–50% or more is normal. o Most people with HF have a reduced LVEF.

• For people with preserved ejection fraction:o Echo shows normal or only mildly abnormal left ventricular

systolic function (LVEF >= 45–50%).o May be evidence of diastolic dysfunction.


Initial management• Refer within 2 weeks if:

o Previous MI (prognosis is poor).o No previous MI but high levels of natriuretic

peptide.• B-type natriuretic peptide (BNP) level above 400 pg/mL

(116 pmol/L), or• N-terminal pro-B-type natriuretic peptide (NT-proBNP)

level above 2000 pg/mL (236 pmol/L).o Severe symptoms.o Pregnant.


Initial management• Refer within 6 weeks:

o If no previous MI and raised levels of natriuretic peptide:

• BNP level between 100–400 pg/mL (29-116 pmol/L), or • NT-proBNP level between 400–2000 pg/mL (47–

236 pmol/L).o If natriuretic peptide levels are normal and:

oClinical suspicion of HF persists and the person is obese or taking drugs which lower natriuretic peptide levels.

oAnother condition is suspected which requires referral.


Initial management

• Where it is not possible to measure natriuretic peptide levels, refer if:o The ECG is abnormal, oro The ECG is normal, but there is still a strong

suspicion of heart failure.


Management awaiting referral• If possible - stop medicines affecting the person’s

heart failure, for example:o Some calcium channel blockers – verapamil and diltiazem, o NSAIDs.

• If symptoms need treatment (but not admission), start a loop diuretic such as:o Furosemide 20 mg/day to 40 mg/day.

• If higher doses are needed:o Check adherence.o Review the differential diagnosiso Seek specialist advice.


Summary• About 50% of people die within 4 years of having a diagnosis of HF. • Treatment with an ACE inhibitor and beta-blocker significantly improves

mortality and morbidity.• To confirm the diagnosis refer for specialist assessment and echo. • Refer within 2 weeks if:

o No previous MI but high levels of natriuretic peptide.o There is a previous MI - no need to measure natriuretic peptides, prognosis is poor.o Severe symptoms or pregnant.

• Refer within 6 weeks if no previous MI and raised levels of natriuretic peptide.• Reconsider diagnosis if natriuretic peptides are not raised.• If unable to measure natriuretic peptides use results of the 12 lead ECG; refer if

o The ECG is abnormal, oro The ECG is normal, but there is still a strong suspicion of heart failure.

• While awaiting referral start a loop diuretic to manage symptoms.

clinical knowledge summaries cks heart failure - chronic diagnosis and initial management in primary...

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