Emory Healthcare is using a new type of implantable cardioverter-defibrillator (ICD) device that helps reduce the risk of dying from cardiac arrest. Emory is the first health care system in Georgia to offer the device, according to a Jan. 9 University press release.
The new device, also known as a subcutaneous or S-ICD, is implanted under the skin on the left side of the chest, unlike a traditional ICD, which uses wires called "leads" that are threaded through a series of veins to the heart, according to Emory School of Medicine Assistant Professor of Cardiology Michael Lloyd.
Whereas conventional ICDs attach to the inside of the heart muscle to deliver electric shocks to the heart, S-ICDs deliver these shocks through an electrode beneath the skin. These shocks help correct arrthymias, or irregular heart rhythms, which can lead to cardiac arrest, according to the National Institutes of Health (NIH).
The NIH states that cardiac arrest occurs when the heart develops an irregular heart rhythm that causes it to stop beating. If not treated properly, cardiac arrest can cause death within minutes. The American Heart Association reported on its website that almost 360,000 incidences of out-of-hospital cardiac arrest occurred in 2013.
Lloyd said S-ICDs present two important advantages over regular ICDs, which can cause dangers and complications in patients. The wires that cross the heart valve in traditional ICDs can potentially cause degeneration and leak of the heart valve. In addition, Lloyd said that having a metal device such as an ICD in the bloodstream could increase the risk of infections. Implanting ICDs under the skin, Lloyd said, eliminates such risks
"Whenever there's transient germs that enter the bloodstream that we all have like when we brush our teeth or when we floss, the germs have a much easier time sticking on metal in the bloodstream and that can pose a source of a bloodstream infection if it's the right circumstances," Lloyd said.
The S-ICD is slightly bigger than a traditional ICD and is surgically implanted under the left armpit, tunneling in an L-shape to the left side of the chest. Lloyd said the S-ICDs have been used in a number of cases at Emory and have proved to be just as tolerable if not more, for the patients.
"We've done a handful over here and we've had good success with them," Lloyd said. "Time will tell if this is going to replace the old-fashioned ones that go in the bloodstream across the heart valve."
Lloyd said he and others at Emory participated in some of the initial clinical trials for the S-ICD. A study published in the journal Circulation found that S-ICDs were efficient and safe to use in the treatment of irregular heart rhythms.
Raul Weiss, an electrophysiologist at Ohio State University and a lead author on the study, said that he was part of the team that got the new device approved by the FDA in late September 2012.
Weiss said that many traditional ICDs also include pacemakers, while S-ICDs do not. He said that he expects S-ICDs to be much more common among patients that do not need pacemakers.
"In other words, it's not a niche product," Weiss said. "I think it will be widely used."
- Contact Harmeet Kaur at hbhagra@emory.edu
Read More
