Pacemakers Go Wireless
Complications are fewer with new, more compact version of the heart-regulation device.
So much in the world of electronics is moving to
wireless. For computers, music systems, phones and other items, the days of connecting wires are going away. And health care is no different. A wireless pacemaker, approved by the Food and Drug Administration in 2016, is giving some heart patients a new and better way to correct a faulty heart rhythm.
Marc Roelke, M.D., director of Electrophysiology at Saint Barnabas Medical Center, prefers the term “leadless” to wireless, because “leads” is the term used for the wires that connect the pacemaker generator (with its battery and computer programming) to the heart muscle. With conventional pacemakers, the generator—as big as a wristwatch—is implanted under the skin in the upper chest near the shoulder, and one to three lead wires run through blood vessels to positions implanted in the heart and deliver the electrical pulses that regulate heartbeat.
The new device, the Micra Transcatheter Pacing System, is made by Medtronic. It’s about the size of a quarter, and Medtronic claims it is the world’s smallest pacemaker. All the components are contained within the Micra, which is inserted through a catheter that is threaded from the femoral vein in the leg up to the right ventricle, the lower right chamber of the heart. It attaches to the heart wall by small tines. Its battery lasts 10 to 12 years, the same as those of conventional pacemakers.
In a study of clinical trial results published in the New England Journal of Medicine, leadless pacing with Micra had 51 percent fewer major complications, such as infection, when compared with traditional pacemakers. The study found that up to six months after implantation, 96 percent of patients experienced no major complications, no dislodgements and no infections. And more than 98 percent of patients had stable heartbeats.
That is not to say that traditional pacemakers are ineffective. “They are excellent,” says David Dobesh, M.D., a cardiac electrophysiologist at Saint Barnabas Medical Center, “but they have limitations.” In some patients it can be difficult to connect the battery in the chest to the heart because of other health conditions, previous surgery or anatomical issues. “The beauty of this new device is that it goes through a vein in the leg and bypasses any vein blockages in the upper extremities,” he says.
In June, Dr. Roelke became the first doctor at Saint Barnabas Medical Center to implant one of the new devices in a patient. “Micra removes the stigma of having a pacemaker—there is no visible scar and no device protruding in the chest,” says Dr. Roelke.
The FDA says the Micra pacemaker is not recommended for patients who have other implanted devices that could interfere with its function—or for those who are severely obese or have an intolerance to materials in the device or to the blood thinner heparin. In addition, patients’ veins must be big enough to accommodate the 7.8-millimeter implant.
Dr. Dobesh says the Micra is now approved for any patient who is a candidate for single-lead devices. (In many cases, that means a patient with a slow heart rate and persistent atrial fibrillation.)
To find out more about cardiovascular services available ayt Saint Barnabas Medical Center, please call 973.322.5244 or go to RWJBH.ORG/SBMCHEART. to share this article with a friend or to recommend it on your facebook page, visit MSXHEALTHANDLIFE.COM.