In final guidance NICE has clearly defined which heart devices – known as implantable cardiac devices – are the most clinically and cost effective. The new guidance will help people with a variety of heart conditions including those with an irregular heartbeat (arrhythmia). Arrhythmia causes 4 out of 5 deaths from sudden cardiac death in England and Wales. 

The guidance is an update of 2 existing pieces of NICE Guidance:

• NICE guidance on the use of implantable cardioverter defibrillators (ICDs) in people who have arrhythmias in the lower chambers of the heart (ventricular arrhythmias).
• NICE guidance on cardiac resynchronisation therapy for people with heart failure. People with heart failure also have an increased risk of developing life threatening ventricular arrhythmias and sudden cardiac death is the most common cause of death in people with mild to moderate heart failure.

Only the recommendations about the use of the different implantable cardiac devices for people at risk of sudden cardiac death because of heart failure have been updated in this guidance. There was no new evidence on the use of ICDs for people who have survived an episode of ventricular tachycardia or ventricular fibrillation, for people with specific inherited cardiac conditions who have a high risk of sudden death or who have undergone surgical repair of congenital heart disease.

People who survive a life-threatening ventricular arrhythmia are at high risk of further arrhythmias and are usually fitted with an ICD. An ICD is a small battery powered device that is put into the upper chest below the left shoulder. Leads from the device go through a vein into the heart to control the rate (pace) of the heartbeat. They continually monitor for an irregular heartbeat, and deliver a small electric shock to return the heartbeat to its normal rhythm (defibrillate) if necessary.

The aim of cardiac resynchronisation therapy (CRT- also known as cardiac resynchronisation pacemaker [CRT-P]) - is to improve the heart’s pumping efficiency by bringing the pumping action of the heart chambers back in time with each other.

Another type of CRT, called CRT-D (combining CRT-P and ICD devices) defibrillates the heart internally if it starts beating irregularly and improves the heart’s pumping efficiency. 

Professor Carole Longson, NICE Health Technology Evaluation Centre Director, said: “Heart problems, particularly of the severity covered by this guidance where there is a high risk of sudden death caused by irregular heartbeats, kills or injures tens of thousands of people each year.

“There are drugs that can prevent arrhythmias but they are often not effective, can have unpleasant side-effects and sometimes need frequent dose adjustments which can be demanding for patients and lead to missed doses, taking the wrong dose or overdose.

“Heart devices can be used to treat and prevent potentially life threatening arrhythmias and heart failure.

“This guidance defines which of the different implantable cardiac devices is a clinically and cost effective treatment option for people who are at risk of sudden cardiac death because of left ventricular dysfunction.” 

Ends

For further information, please contact the NICE press office on 0300 323 0142/ pressoffice@nice.org.uk or out of hours on 07775 583 813.

Notes to Editors

References

1. Arrhythmia describes a condition caused by an abnormality in the heart muscle or in the electrical conduction system of the heart which causes the heart to beat irregularly or at a faster or slower pace than normal. Ventricular arrhythmias are most common in people with underlying heart disease. They can happen suddenly and unexpectedly, and can cause sudden death. Over 50,000 people die suddenly each year in England from heart problems caused by ‘fast’ arrhythmias in the ventricles (conditions called ventricular tachycardia or ventricular fibrillation).
2. Heart failure is a complex condition that reduces the heart’s ability to function efficiently as a pump. One cause of heart failure is left ventricular systolic dysfunction (LVSD) where the left ventricle starts pumping out of time with the rest of the heart. LVSD is associated with a reduced left ventricular ejection fraction (The amount of oxygen rich blood that is pumped out of the left ventricle per heartbeat. It is used to measure how well the heart is working. A normal LVEF is 50–70%). People with heart failure also have an increased risk of developing life threatening ventricular arrhythmias and sudden cardiac death is the most common cause of death in people with mild to moderate heart failure.

About the guidance

The guidance states that:

1. Implantable cardioverter defibrillators (ICDs) are recommended as options for:

• treating people with previous serious ventricular arrhythmia, that is, people who, without a treatable cause:
• have survived a cardiac arrest caused by either ventricular tachycardia (VT) or ventricular fibrillation or
• have spontaneous sustained VT causing syncope or significant haemodynamic compromise or
• have sustained VT without syncope or cardiac arrest, and also have an associated reduction in left ventricular ejection fraction (LVEF) of 35% or less but their symptoms are no worse than class III of the New York Heart Association (NYHA) functional classification of heart failure.
• treating people who:
• have a familial cardiac condition with a high risk of sudden death, such as long QT syndrome, hypertrophic cardiomyopathy, Brugada syndrome or arrhythmogenic right ventricular dysplasia or
• have undergone surgical repair of congenital heart disease.

2. Implantable cardioverter defibrillators (ICDs), cardiac resynchronisation therapy (CRT) with defibrillator (CRT‑D) or CRT with pacing (CRT‑P) are recommended as treatment options for people with heart failure who have left ventricular dysfunction with a left ventricular ejection fraction (LVEF) of 35% or less as specified in table 1.

Table 1 Treatment options with ICD or CRT for people with heart failure who have left ventricular dysfunction with an LVEF of 35% (according to NYHA class, QRS duration and presence of left bundle branch block (LBBB))

About arrhythmias

1. The average survival of adults with an out of hospital episode of ventricular arrhythmia has been reported as low as 7%. With appropriate treatment and secondary preventive strategies, recent studies have reported 5 year survival of 69 to 100%.
2. Many patients presenting with arrhythmias with or without symptoms are treated with anti-arrhythmic drug therapy. Anti-arrhythmic drugs are often not effective and need  constant titration which can be confusing for patients and lead to missing doses, taking the wrong dose or overdose. Many anti-arrhythmic drugs result in tiredness and inability to perform day to day activities, dependence on carers and consequently increase the risk of depression. Anti-arrhythmic drugs also have many side effects on the thyroid, liver or lungs.
3. Chronic prophylactic anti-arrhythmic drug therapy aims to suppress the development of arrhythmias, but does not terminate an arrhythmia once it is initiated. People who survive a first episode of a life-threatening ventricular arrhythmia are at high risk of further episodes and usually treated with implantable cardioverter defibrillators (ICDs).
4. Risk factors for sudden cardiac death include age, hereditary factors, having high risk of for coronary artery disease, inflammatory markers, hypertension, left ventricular hypertrophy, conduction abnormalities (for example left bundle-branch block), obesity, diabetes and lifestyle factors.

About heart failure

1. Heart failure is a chronic condition predominantly affecting people over the age of 50 years. It is a condition caused by any structural or functional cardiac disorder that impairs the heart’s ability to function efficiently as a pump to support circulation. It is characterised by breathlessness, fatigue and fluid retention. About 900,000 people in England and Wales have heart failure, of which at least half have LVSD.
2. Clinically heart failure is classified using the New York Heart Association (NYHA) functional class, ranging from Class I (no limitation of physical activity) to Class IV (symptomatic at rest and discomfort from any physical activity).
3. Heart failure is also classified based on which heart function or which side of the heart is most affected: some patients have heart failure due to left ventricular systolic dysfunction (LVSD) which is associated with a reduced left ventricular ejection fraction (left heart failure or biventricular failure); while others have only right heart failure with a preserved ejection fraction.
4. Management of chronic heart failure in adults in primary and secondary care” initially recommends pharmacological treatment.  However, as the condition becomes more severe, cardiac function and symptoms may no longer be controlled by pharmacological treatment and require invasive procedures. Cardiac function and heart failure symptoms may be improved by the implantation of a cardiac rhythm device which can sense and stimulate the atria, right and left ventricles independently.