Prevalence and Presentation of Externalized Conductors and Electrical Abnormalities in Riata Defibrillator Leads After Fluoroscopic Screening

Abstract

Background-The Riata family of implantable cardioverter-defibrillator (ICD) leads is prone to a specific insulation abrasion characterized by externalization of conductor cables. The objective of this study was to determine the prevalence of externalized conductors and electrical abnormalities in Riata ICD leads by fluoroscopic screening and standard ICD interrogation. Methods and Results-All ICD implantation centers were contacted by the Netherlands Heart Rhythm Association Device Advisory Committee to identify all patients with an active Riata ICD lead and to perform fluoroscopic screening of the lead. In addition, the electrical integrity of the lead was assessed. As of March 1, 2012, data for 1029 active Riata leads were available; 47% of these were 8-F Riata and 53% were 7-F Riata ST. Externalized conductors were observed in 147 leads (14.3%). Proportion of externalized conductors was higher in 8-F Riata compared with 7-F Riata ST (21.4% vs 8.0%; P<0.001). Median time from implantation to detection of externalized conductors was 65.3 months. The estimated rates of externalized conductors were 6.9% and 36.6% at 5 and 8 years after implantation, respectively. Of the 147 leads with externalized conductors, 10.9% had abnormal electrical parameters vs 3.5% in nonexternalized leads (P<0.001). Conclusions-The

Cable externalization and electrical failure of the Riata family of implantable cardioverter-defibrillator leads: A systematic review and meta-analysis

“…Prevalence of CE ranged from 11% to 43% ( Figure 2A). 6,[10][11][12][13][15][16][17][19][20][21][22]25 Based on random effects modeling, the overall rate of CE was 23.1% (95% CI 19.0%-27.6%). In most but not all of these 13 studies, an average lead dwell time was reported (range 3.5-6.2 years).…”

Performance of Lead Integrity Alert to Assist in the Clinical Diagnosis of Implantable Cardioverter Defibrillator Lead Failures

“…1 The lead is the weakest link in all ICD systems: multiple studies have shown failure rates ranging from 10% to 50% during long-term follow-up and smaller lead size may be a predictor of a higher failure rate. [2][3][4][5][6] Even with alerts based on absolute values of pacing impedance, the most common presentation of lead failure (LF) is inappropriate shocks [1][2][3][4] delivered in response to rapid oversensing of nonphysiological signals. To improve detection of LF compared with conventional impedance monitoring, the Lead Integrity Alert (LIA) 7,8 was developed, which is triggered by relative changes in impedance and evidence of transient, rapid oversensing.…”

Insight into the mechanism of failure of the Riata lead under advisory

“…Cheung et al 5 reported on 314 patients and found a significantly higher rate of externalized conductors (57%) in failed leads than did other investigators. 5,[8][9][10] This difference may relate to implantation technique or dedicated surveillance at this single center that resulted in a greater proportion of externalization than seen in our study. Previous studies have examined venous approach, degree of slack in leads, lead placement in the pocket, and degree of curvature in the lead as it passes through the tricuspid valve as it relates to ICD fracture.…”