A study, published in New England Journal of Medicine, describes the use of a new pacemaker that can be implanted into the heart without the necessity for surgery to test its safety and efficacy in fragile patients who require permanent pacing for normal functioning of the heart.
The device, the Nanostim from St. Jude Medical, which only measures 6mm in diameter and 42mm in length, can be implanted into either side of the heart using a catheter inserted via the leg arteries, similar to how stents are currently placed. Moreover, unlike traditional pacemakers, the device does not need an external generator or wires to function. Instead, a small battery with an estimated lifetime of 15 years is built into the device.
“This is another landmark in the development of pacemakers” said Dr. Christopher Granger of the American Heart Association, who was not part of the new study. However, he cautions that more testing needs to be done before the device can function well in patients. The pacemaker has already been approved for use in Europe and is to be submitted to the US Food and Drug Administration (FDA) soon.
From the results section of the study abstract:
The leadless pacemaker was successfully implanted in 504 of the 526 patients in the total cohort (95.8%). The intention-to-treat primary efficacy end point was met in 270 of the 300 patients in the primary cohort (90.0%; 95% confidence interval [CI], 86.0 to 93.2, P=0.007), and the primary safety end point was met in 280 of the 300 patients (93.3%; 95% CI, 89.9 to 95.9; P<0.001). At 6 months, device-related serious adverse events were observed in 6.7% of the patients; events included device dislodgement with percutaneous retrieval (in 1.7%), cardiac perforation (in 1.3%), and pacing-threshold elevation requiring percutaneous retrieval and device replacement (in 1.3%).
Study in New England Journal of Medicine: Percutaneous Implantation of an Entirely Intracardiac Leadless Pacemaker…