Boston Scientific‘s (NYSE:BSX) subcutaneous implantable cardioverter defibrillators showed high rates of successful therapy and low rates of inappropriate pacing in data from the 1st large, real-world clinical trial of the novel device.
Researchers followed more than 450 patients for an average of more than 1.5 years, reporting a 100% treatment rate for spontaneous ventricular tachyarrhythmias and a 99.7% treatment rate for acute ventricular tachyarrhythmias at 12 months. The researchers also reported a 6.4% rate of inappropriate shocks, similar to results for traditional ICDs.
"The EFFORTLESS registry publication provides even more supportive evidence for this innovative therapy," Boston Scientific CMO Dr. Kenneth Stein said in prepared remarks. "These long-term results in a large patient cohort are comparable to similar data for transvenous ICDs and should help physicians as they decide which patients are the best candidates for the S-ICD System."
The report is the largest to date to examine the S-ICD system, reflecting findings from centers all over the world. The device has been on the European market since 2009 and won FDA approval for the U.S. in 2012. Boston Scientific acquired the S-ICD technology in June 2012 when it acquired Cameron Health in a deal worth $1.35 billion.
Traditional implanted defibrillators require wire leads that are threaded into the heart to provide shock therapy to interrupt abnormal heart rhythms. The technology has been around for some 30 years, but the leads are the "Achilles heal" of the device, EFFORTLESS researchers wrote. The wires pose a risk of complications, especially for younger patients who may have to have the leads replaced at some point.
Cameron Health developed the world’s 1st and only lead-free implantable cardioverter defibrillator, which sits just under the skin and, unlike traditional ICDs, does not require leads threaded into the heart.
More studies are needed to suss out the true benefits of subcutaneous versus transvenous ICDs, the researchers cautioned, citing ongoing head-to-head studies that should provide a clearer sense of when S-ICDs should be offered as a 1st-line therapy. Further research is also needed to highlight long-term use of the device.
The EFFORTLESS S-ICD trial is slated to enroll 1,000 patients and amass 5 years of follow-up data.