Fluoroscopic and electrical assessment of implantable cardioverter defibrillator leads: a prospective observational study.

Background: Insulation defects resulting in conductor externalization (CE) have been reported in the Riata family of implantable cardioverter defibrillator (ICD) leads (St. Jude Medical, Sylmar, CA, USA). The aim of this study was to identify, prospectively, the rate of CE and outcomes following this, within a group of patients with a Riata ICD lead.

Methods: Patients with a Riata ICD lead attended for fluoroscopic screening and electrical assessment of the lead at yearly intervals between 2010 and 2012.

Results: One hundred and forty patients had no or borderline evidence of CE on initial assessment in 2010. These patients were prospectively followed for 3 years (304.6 patient-years). During this time, 11 patients developed definite CE, equating to an event rate of 3.6 (95% confidence intervals: 1.8-6.5) per 100 patient-years of follow-up. Of those patients developing definite CE, one patient had the ICD lead explanted (for reasons unrelated to CE) and no patients died. CE was not associated with any electrical abnormalities of the ICD lead.

Conclusions: CE was observed at a rate of 3.6 per 100 patient-years of follow-up, in 140 individuals with a Riata ICD lead and no definite evidence of CE at baseline.