From the May 2015 issue of HealthCare Business News magazine


Patients with an underlying cardiovascular condition that puts them at risk of cardiac arrest may be candidates for these internal systems, which deliver shock in a timely fashion and offer survival rates upwards of 98 or 99 percent. However, transvenous defibrillators are not without their drawbacks. Dr. Kenneth Stein, chief medical officer for Rhythm Management at Boston Scientific, says the human heart beats approximately 100,000 times per day.

Over the course of many years, that puts a strain on these wires. That means even the best transvenous defibrillators have a failure rate around one percent after seven to ten years. If an infection develops and the transvenous ICD has to be removed, a laser must be used to melt the scar tissue and free up the wire. That presents another potential problem. “As these wires are present in the body for extended periods of time, years typically, anchoring fibrosis develops,” says Dr. Daniel Cantillon, cardiologist at Cleveland Clinic, “which means scar tissue is developing in the veins that hold the wire closely to the blood vessel and the heart itself.”


A new approach to internal defibrillators was pioneered by Cameron Health, a company Boston Scientific invested in and later purchased. With subcutaneous ICDs the lead does not have to run through blood vessels but instead utilizes a pulse generator and electrode beneath the skin. S-ICD does not have those kinds of removal complications. Instead, they provide a way to avoid navigating blood vessels with the lead by using a shocking coil that is planted and tunneled through the soft tissues of the body from the space just under the left arm—the axilla region—up, just to the left of the breast bone.

These systems are still in their first generation but Stein says developers are looking for ways to implement some of the more advanced features of transvenous ICDs into S-ICDs. That means better battery longevity, smaller size, and remote monitoring capabilities.

“Remote monitoring technology is a really important and useful feature as you look to the long-term,” says Stein, who says his company’s transvenous ICD systems already feature EHR integration. Even with those added features, there is a drawback to S-ICD systems that could make a transvenous system better for certain patients. “A traditional ICD can serve as both an ICD and a pacemaker,” says Cantillon, “so for patients who need both, the traditional version is more appropriate.”

Data and maintenance
Defibrillators are linking up with hospital IT in the interest of yielding better insight into patient care as well as quality assurance and monitor readiness information. “The biomed in a given hospital could be responsible for keeping 200-300 crash cart defibrillators ready at all times,” says White.

May 2015 Magazine

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