Chronic heart failure refers to the clinical features of impaired heart function, specifically the function of the left ventricle to pump blood out of the heart and around the body.
Impaired left ventricular function results in a chronic backlog of blood waiting to flow into and through the left side of the heart. The left atrium, pulmonary veins and lungs experience an increased volume and pressure of blood. They start to leak fluid and cannot reabsorb excess fluid from the surrounding tissues, resulting in pulmonary oedema.
The ejection fraction is the percentage of blood in the left ventricle squeezed out with each ventricular contraction. An ejection fraction above 50% is considered normal.
Heart failure with reduced ejection fraction is when the ejection fraction is less than 50%.
Heart failure with preserved ejection fraction is when someone has the clinical features of heart failure but an ejection fraction greater than 50%. This is the result of diastolic dysfunction, where there is an issue with the left ventricle filling with blood during diastole (the ventricle relaxing).
Causes
- Ischaemic heart disease
- Valvular heart disease (commonly aortic stenosis)
- Hypertension
- Arrhythmias (commonly atrial fibrillation)
- Cardiomyopathy
Presentation
The key symptoms of chronic heart failure are:
- Breathlessness, worsened by exertion
- Cough, which may produce frothy white/pink sputum
- Orthopnoea, which is breathlessness when lying flat, relieved by sitting or standing (ask how many pillows they use)
- Paroxysmal nocturnal dyspnoea (more detail below)
- Peripheral oedema
- Fatigue
Signs on examination include:
- Tachycardia (raised heart rate)
- Tachypnoea (raised respiratory rate)
- Hypertension
- Murmurs on auscultation indicating valvular heart disease
- 3rd heart sound on auscultation
- Bilateral basal crackles (sounding “wet”) on auscultation of the lungs, indicating pulmonary oedema
- Raised jugular venous pressure (JVP), caused by a backlog on the right side of the heart, leading to an engorged internal jugular vein in the neck
- Peripheral oedema of the ankles, legs and sacrum
Paroxysmal Nocturnal Dyspnoea
Paroxysmal nocturnal dyspnoea (PND) describes the experience that patients have of suddenly waking at night with a severe attack of shortness of breath, cough and wheeze.
They may describe having to sit on the side of the bed or walk around the room, gasping for breath. They may feel suffocated and want to open a window to get fresh air. Symptoms improve over several minutes.
There are a few proposed mechanisms to explain paroxysmal nocturnal dyspnoea.
Firstly, fluid settles across a large surface area of the lungs as they lie flat to sleep, causing breathlessness. As they stand up, the fluid sinks to the lung bases, and the upper lung areas function more effectively.
Secondly, during sleep, the respiratory centre in the brain becomes less responsive, so the respiratory rate and effort do not increase in response to reduced oxygen saturation like they would when awake. This allows the person to develop more significant pulmonary congestion and hypoxia before they wake up feeling very unwell.
Thirdly, there is less adrenalin circulating during sleep. Less adrenalin means the myocardium is more relaxed, reducing cardiac output.
Assessment
Establishing a diagnosis of heart failure involves:
- Clinical assessment (history and examination)
- N-terminal pro-B-type natriuretic peptide (NT‑proBNP) blood test
- ECG
- Echocardiogram
Other investigations include:
- Bloods for anaemia, renal function, thyroid function, liver function, lipids and diabetes
- Chest x-ray and lung function tests to exclude lung pathology
New York Heart Association Classification
The New York Heart Association (NYHA) classification system is used to grade the severity of symptoms related to heart failure. Here is a simplified summary:
- Class I: No limitation on activity
- Class II: Comfortable at rest but symptomatic with ordinary activities
- Class III: Comfortable at rest but symptomatic with any activity
- Class IV: Symptomatic at rest
Management
The management here is summarised based on NICE guidelines from 2018 and the NICE clinical knowledge summaries (updated January 2023). Follow local and national guidelines and get input from seniors when treating patients.
There are five principles of management. You can remember this with the “RAMPS” mnemonic:
- R – Refer to cardiology
- A – Advise them about the condition
- M – Medical treatment
- P – Procedural or surgical interventions
- S – Specialist heart failure MDT input, such as the heart failure specialist nurses, for advice and support
The urgency of the referral and specialist assessment depends on the NT-proBNP result. According to the NICE guidelines:
- From 400 – 2000 ng/litre should be seen and have an echocardiogram within 6 weeks
- Above 2000 ng/litre should be seen and have an echocardiogram within 2 weeks
Additional management:
- Flu, covid and pneumococcal vaccines
- Stop smoking
- Optimise treatment of co-morbidities
- Written care plan
- Cardiac rehabilitation (a personalised exercise programme)
Medical Treatment
The first-line medical treatment of chronic heart failure can be remembered with the “ABAL” mnemonic:
- A – ACE inhibitor (e.g., ramipril) titrated as high as tolerated
- B – Beta blocker (e.g., bisoprolol) titrated as high as tolerated
- A – Aldosterone antagonist when symptoms are not controlled with A and B (e.g., spironolactone or eplerenone)
- L – Loop diuretics (e.g., furosemide or bumetanide)
An angiotensin receptor blocker (ARB) (e.g., candesartan) can be used instead of an ACE inhibitor if not tolerated. Avoid ACE inhibitors in patients with valvular heart disease until initiated by a specialist.
Aldosterone antagonists are used when there is a reduced ejection fraction and symptoms are not controlled with an ACEi and beta blocker.
Patients should have their U&Es closely monitored whilst taking diuretics, ACE inhibitors and aldosterone antagonists, as all three medications can cause electrolyte disturbances. It is particularly essential to closely monitor the renal function in patients taking ACE inhibitors and aldosterone antagonists. Both can cause hyperkalaemia (raised potassium), which is potentially fatal.
Additional specialist treatments in patients with heart failure are:
- SGLT2 inhibitor (e.g., dapagliflozin)
- Sacubitril with valsartan (brand name Entresto)
- Ivabradine
- Hydralazine with a nitrate
- Digoxin
Procedural and Surgical Interventions
Surgical procedures may be used to treat underlying valvular heart disease.
Implantable cardioverter defibrillators continually monitor the heart and apply a defibrillator shock to cardiovert the patient back into sinus rhythm if they identify a shockable arrhythmia. These are used in patients who previously had ventricular tachycardia or ventricular fibrillation.
Cardiac resynchronisation therapy (CRT) may be used in severe heart failure, with an ejection fraction of less than 35%. CRT involves biventricular (triple chamber) pacemakers, with leads in the right atrium, right ventricle and left ventricle. The objective is to synchronise the contractions in these chambers to optimise heart function.
A heart transplant may be considered in suitable patients with severe disease.
Last updated March 2023
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