More than 2 million people experience cardiac arrhythmia each year in the UK. Atrial fibrillation, supraventricular tachycardia, bradycardia, heart block and ventricular fibrillation are the main types of arrhythmia (NHS Choices 2015). Ventricular arrhythmias caused about 75–80% of the 70,000 sudden cardiac deaths in England and Wales in 2010 (NICE technology appraisal on implantable cardioverter defibrillators and cardiac resynchronisation therapy). In addition, around 900,000 people in the UK have heart failure, commonly caused by coronary artery disease and previous heart attack (NICE guideline on chronic heart failure in adults). Both arrhythmia and heart failure can significantly affect a person's quality of life as well as putting them at risk of sudden cardiac death.

The first-line treatment for arrhythmia and heart failure focuses on pharmacological therapy but when this is no longer effective or can no longer be used, one of the following implantable cardiac devices may be used:

  • Pacemaker: monitors the heart's rhythm and sends small electrical pulses to restore normal rhythm if needed.

  • Implantable cardioverter defibrillator: like a pacemaker, but can send larger electrical shocks for more serious heart rhythm problems that pacemakers cannot correct.

  • Cardiac resynchronisation with pacing device: improves the heart's pumping efficiency.

  • Cardiac resynchronisation therapy with a defibrillator device: combines cardiac resynchronisation with pacing and implantable cardioverter defibrillator.

  • Implantable loop recorder: records the heart's rhythm to provide information to help guide clinical decision-making.

People with implantable electronic cardiovascular devices need regular monitoring of their condition and to ensure that the device is working correctly, to check battery life and to optimise the device where applicable. Monitoring is usually done in a hospital outpatient setting at defined regular intervals. Home monitoring technology offers another option, so that clinicians can monitor the person's device remotely. This could reduce the frequency of hospital visits, and may also help with faster identification of abnormalities.