Classification

The New York Heart Association (NYHA) classification is widely used to classify the severity of heart failure:

NYHA Class I
  • no symptoms
  • no limitation: ordinary physical exercise does not cause undue fatigue, dyspnoea or palpitations

NYHA Class II
  • mild symptoms
  • slight limitation of physical activity: comfortable at rest but ordinary activity results in fatigue, palpitations or dyspnoea

NYHA Class III
  • moderate symptoms
  • marked limitation of physical activity: comfortable at rest but less than ordinary activity results in symptoms

NYHA Class IV
  • severe symptoms
  • unable to carry out any physical activity without discomfort: symptoms of heart failure are present even at rest with increased discomfort with any physical activity

Epidemiology

  • Incidence: 200.00 cases per 100,000 person-years
  • Peak incidence: 70+ years
  • Sex ratio: 1:1
Condition Relative
incidence
Chronic heart failure1
Pulmonary arterial hypertension0.002
<1 1-5 6+ 16+ 30+ 40+ 50+ 60+ 70+ 80+

Clinical features

Features:
  • dyspnoea
  • cough: may be worse at night and associated with pink/frothy sputum
  • orthopnoea
  • paroxysmal nocturnal dyspnoea
  • wheeze ('cardiac wheeze')
  • weight loss ('cardiac cachexia'): occurs in up to 15% of patients. Remember this may be hidden by weight gained secondary to oedema
  • bibasal crackles on examination
  • ankle oedema

Investigations

NICE issued updated guidelines on diagnosis and management in 2018. Previously the first-line investigation was determined by whether the patient has previously had a myocardial infarction or not this is no longer the case - all patients should have an N-terminal pro-B-type natriuretic peptide (NT‑proBNP) blood test first-line.

Interpreting the test
  • if levels are 'high' arrange specialist assessment (including transthoracic echocardiography) within 2 weeks
  • if levels are 'raised' arrange specialist assessment (including transthoracic echocardiography) echocardiogram within 6 weeks

Serum natriuretic peptides

B-type natriuretic peptide (BNP) is a hormone produced mainly by the left ventricular myocardium in response to strain. Very high levels are associated with a poor prognosis.

BNP NTproBNP
High levels> 400 pg/ml (116 pmol/litre)> 2000 pg/ml (236 pmol/litre)
Raised levels100-400 pg/ml (29-116 pmol/litre)400-2000 pg/ml (47-236 pmol/litre)
Normal levels< 100 pg/ml (29 pmol/litre)< 400 pg/ml (47 pmol/litre)

Factors which alter the BNP level:

Increase BNP levelsDecrease BNP levels
Left ventricular hypertrophy
Ischaemia
Tachycardia
Right ventricular overload
Hypoxaemia (including pulmonary embolism)
GFR < 60 ml/min
Sepsis
COPD
Diabetes
Age > 70
Liver cirrhosis
Obesity
Diuretics
ACE inhibitors
Beta-blockers
Angiotensin 2 receptor blockers
Aldosterone antagonists

Management

NICE issued updated guidelines on management in 2010, key points include:
  • first-line treatment for all patients is both an ACE-inhibitor and a beta-blocker*. Generally, one drug should be started at a time
  • second-line treatment is now either an aldosterone antagonist, angiotensin II receptor blocker or a hydralazine in combination with a nitrate
  • if symptoms persist cardiac resynchronisation therapy or digoxin** should be considered. An alternative supported by NICE in 2012 is ivabradine. The criteria for ivabradine include that the patient is already on suitable therapy (ACE-inhibitor, beta-blocker + aldosterone antagonist), has a heart rate > 75/min and a left ventricular fraction < 35%
  • diuretics should be given for fluid overload
  • offer annual influenza vaccine
  • offer one-off*** pneumococcal vaccine

Other drugs
  • sacubitril-valsartan is considered in heart failure with reduced ejection fraction who are symptomatic on ACE inhibitors or ARBs
  • sacubitril-valsartan should be initiated following ACEi or ARB wash-out period


Cardiac resynchronisation therapy
  • for patients with heart failure and wide QRS
  • biventricular pacing
  • improved symptoms and reduced hospitalisation in NYHA class III patients

Exercise training
  • improves symptoms but not hospitalisation/mortality


*ACE-inhibitors and beta-blockers have no effect on mortality in heart failure with preserved ejection fraction

**digoxin has also not been proven to reduce mortality in patients with heart failure. It may however improve symptoms due to its inotropic properties. Digoxin is strongly indicated if there is coexistent atrial fibrillation

***adults usually require just one dose but those with asplenia, splenic dysfunction or chronic kidney disease need a booster every 5 years