Cardiac failure

Class I Cardiac disease that does not limit normal physical activity.
(Normal physical exertion is not associated with undue fatigue, dyspnoea, or angina pain.)
Class II Patients with cardiac disease causing slight limitation of physical activity.
(Comfortable at rest, ordinary physical activity results in fatigue, palpitation, SOB or angina)
Class III Patients with cardiac disease causing marked limitation of their physical activity.
(Comfortable at rest, < ordinary physical activity causes fatigue, palpitation, SOB, or angina).
Class IV Patients with cardiac disease that prevents them carrying out any physical activity without discomfort and onset of symptoms. (Symptoms may be present at rest (angina, SOB). Symptoms increase with any physical activity)

Perform echocardiography in patients with certainor probable heart failure to refine the diagnosis and plan treatment
Measurebrain natriuretic peptide (BNP) in patients with an uncertaindiagnosis
A normal BNP result is better than electrocardiographyfor diagnosing heart failure and rules out heart failure; ifraised perform echocardiography
Echocardiography can determinethe underlying structure and function of heart failure
It iscrucial to distinguish heart failure with low ejection fractionfrom that with preserved ejection fraction because most highquality evidence on treatment is for patients with low ejectionfraction
While waiting for echocardiography (or if not available)give an angiotensin converting enzyme inhibitor and β blocker(where possible) and uptitrate to maximum doses

Class	Symptoms	Treatment if left ventricular ejection fraction is low	Treatment if left ventricular ejection fraction is preserved
Class I (mild)	No limitation of physical activity; ordinary physical activity does not cause undue fatigue, palpitation, or dyspnoea (shortness of breath)	ACE inhibitor*; consider a β blocker ${dagger}$
Class II (mild)	Slight limitation of physical activity; comfortable at rest, but ordinary physical activity results in fatigue, palpitation, or dyspnoea	ACE inhibitor; β blocker; candesartan $§$ (specialist advice needed if adding to an ACE inhibitor)	Candesartan (specialist advice needed)
Class III (moderate)	Marked limitation of physical activity; comfortable at rest, but less than ordinary activity causes fatigue, palpitation, or dyspnoea	ACE inhibitor; β blocker; candesartan (specialist advice needed if adding to an ACE inhibitor); spironolactone ${ddagger}$ ; digoxin	Candesartan (specialist advice needed)
Class IV (severe)	Cannot carry out any physical activity without discomfort; symptoms of cardiac insufficiency at rest; discomfort increases if any physical activity is undertaken	ACE inhibitor; carvedilol or bisoprolol as β blocker; spironolactone ${ddagger}$ ; digoxin	Candesartan (specialist advice needed)

*Any angiotensin converting enzyme inhibitor (ACE) inhibitor is recommended but not all have been evaluated in clinical trials.
${dagger}$ Recommended β blockers are carvedilol, bisoprolol, nebivolol, and metoprolol succinate (not available in the UK).
${ddagger}$ Avoid giving an ACE inhibitor, angiotensin receptor blocker, and spironolactone together because of the risk of hypotension and hyperkalaemia.
$§$ Uncertainty exists about angiotensin receptor blockers as a class because irbesartan is not effective whereas candesartan is.