Boston Scientific (NYSE:BSX) today unveiled strong 22-month results for its subcutaneous implantable cardioverter defibrillator, saying the device continues to show efficacy with low rates of complications.
The S-ICD device showed greater than 79% freedom from complications at 22 months, and the device terminated 96% of cardiac episodes with one or more shocks, according to research presented today during Heart Rhythm 2014, the Heart Rhythm Society’s 35th Annual Scientific Sessions. Findings came from the S-ICD IDE trial, which Boston Scientific used to support the FDA approval it won in 2012.
None of the deaths reported in the trial were associated with device-related issues, lead author Dr. Angel Leon said today.
The session was another in a string of reports coming out this week about the S-ICD device, which has been the subject of a lot of buzz at this year’s HRS conference. A well attended poster session yesterday also found strong safety results for S-ICD, with low rates of complications at 2 years.
The most common S-ICD complications were inappropriate shocks, device movement and position issues, and erosion or infection, but rates remained within allowed parameters for safety. Of the 314 patients implanted with the device, 10 required "invasive action" for inappropriate shock, 8 for electrode or pulse generator movement/position issues, 5 for discomfort, 4 for erosion and 4 for system infection, according to the study.
All reported device-related complications cropped up only in centers’ early implants, suggesting that complications may dwindle as clinicians become more experienced implanting with the device, Leon noted.
Another trial examined S-ICD outcomes following explantation of a transvenous ICD in patients that had experienced infections with the traditional implants. Prior studies have reported that ICD extraction patients face a mortality rate of up to 25% following implantation of a new transvenous ICD, indicating an important area of clinical need, lead author Dr. L.V. Boersma noted.
In data pooled from the IDE study and Boston Scientific’s EFFORTLESS trial, researchers examined more than 850 S-ICD patients, 87 of which had a prior transvenous implant removed for infection. The remaining patients either had no previous implant or had their devices removed for reasons other than infection.
Of the non-infection group, 1% developed an infection within 1 year and 1.8% died. In the post-infection group, which was generally older and sicker, 1.1% developed an infection with in 1 year and 2.3% died.
Patients that did develop S-ICD-related infections were able to undergo explantation, and no reported deaths were associated with the S-ICD system or its extraction.