According to the European Society of Cardiology, around 10% of the 700,000 pacemakers implanted worldwide every year are associated with lead-related problems.
Pacemakers are small devices implanted into the chest or abdomen to treat arrhythmia, as they can help an abnormal heart beat at a normal rate using electric impulses.
Since the first artificial pacemaker was implanted in 1958, the technology has continued to advance in terms of longevity, functionality, and compactness. However, this progression has not changed the fact that implantation still requires a complicated surgical procedure. A pocket is created in the chest for the pacemaker and one or more leads are introduced into cardiac chambers to deliver pacing therapy. These devices are also at a disadvantage when it comes to the device-holding pocket, as it is prone to infection and lead failures.
This problem is overcome by leadless pacemakers as they have fewer complications. Leadless pacemakers are small, cylindrical devices measuring 26mm to 46mm in size. They are delivered via the femoral vein with a steerable, deflectable catheter, which can be repositioned based on certain electrical parameters. They attach directly to the endocardium of the heart’s right ventricle and do not need any leads or pockets, decreasing chances of infection.
Leadless devices also have an advantage when it comes to patient comfort and ensuring safety during magnetic resonance imaging (MRI) procedures. In addition, the device eliminates the visible lump and scar caused by conventional pacemakers. However, the future of these miniatures is unknown as there is not enough data about their longevity, battery life, and retrieval from the body.
Medtronic introduced Micra, which claims to have a battery life of 12 years as compared to the average battery lifespan of six to seven years for conventional pacemakers. The downside of Micra is that it costs twice as much as a conventional device. There are also concerns over its retrieval from the heart in case of infection, reposition, or re-implant. According to Medtronic, the design of Micra enables it to be taken out when needed, but it is intended to be left in the body. Patients in need of another device will have their old pacemaker turned off and a new one inserted. St.Jude Medical, an American global medical device company, claims that its Nanostim device is smaller in diameter and easily retrievable.