Abstract 18017: Low Prevalence of Electrical Failure in St. Jude Riata Family ICD Leads with Externalized Cables
BACKGROUND AND HYPOTHESIS: Silicone insulation disruption in St. Jude Riata family implantable cardioverter defibrillator (ICD) leads with externalization of high voltage or sensing cables has been recently reported.The prevalence of extruded cables and their impact on electrical integrity of the lead and clinical outcome remains unclear.
METHODS: All patients with St. Jude Riata family ICD leads being followed at our institution that consented for fluoroscopic evaluation of their leads were enrolled in this study. High-resolution fluoroscopy in the right anterior oblique 45°, left anterior oblique 45° and anteroposterior projections were examined with aim to identify any externalized cables. Electrical data and patient characteristics were compared between the groups with and without externalization. Patients are being followed with annual fluoroscopy and 6 monthly device interrogation.
RESULTS: Occurrence of externalized cables was identified in 25 (17%) of 147 patients with St. Jude Riata family ICD leads. The site of externalization was identified just proximal to the right ventricular coil in the region of tricuspid valve in most of the (23/25) patients and near the pulse generator in the remaining two. Electrical abnormalities requiring lead revision were noted in1(4%) of the patients with externalized leads compared to 0.8% without externalization(P=0.31).(Electrical data is presented in the table below). There were no inappropriate shocks noted in patients with externalized leads. Follow up period since lead placement was significantly longer in patients with externalized cables than those without (72.3±12.3 months vs 65.4±18.5 months, p= 0.02).
CONCLUSIONS: Prevalence of externalized cables in St. Jude Riata family ICD leads was high and increased with time from lead placement. However, this did not impact electrical lead integrity in majority probably because externalized cables remained insulated by ethylene tetrafluoroethylene.
- © 2012 by American Heart Association, Inc.