Leadless Pacemakers: practice and promise in congenital heart disease

The development of the implantable cardiac pacemaker nearly 60 years ago represented a paradigm shift in the control of potentially lethal heart rhythms and has revolutionized the lives of those at risk of sudden death from bradycardia. Subsequent technological developments have resulted in devices that offer additional benefits to patients, including defibrillation and resychronisation therapy. Previously, Cardiac Implantable Electronic Devices (CIEDs) relied on leads, either transvenous or epicardial, to transmit electronic impulses to the heart. The potential value of self-contained leadless intracardiac pacemaker devices has long be recognised with their potential to avoid intrinsic problems with traditional CIEDs, particularly device-related infection and lead failure. Two leadless devices have been introduced since 2012 which may offer a safe, long term alternative to leaded CIEDs with greater patient acceptability and greater flexibility, particularly for congenital heart disease patients where venous access problems may otherwise limit access to traditional transvenous systems. Here we examine the development of leadless pacemakers, the current state of affairs in clinical practice, and key considerations for future developments, with a focus on the usage of such devices in the setting of congenital heart disease.