Nationwide Longitudinal Follow-Up of Riata Leads Under Advisory at 3 Annual Screenings: Report From the Netherlands...

This study sought to determine prospectively the rate of conductor externalization (CE), and whether this was associated with electrical failure.

The Riata family of defibrillator leads was placed under U.S. Food and Drug Administration advisory as of November 28, 2011 because of high rates of CE.

A nationwide cohort established in 2012 of 1,029 patients with recalled Riata leads with 147 CE were followed until death, lead discontinuation, or 3 annual screenings with fluoroscopy and device interrogation.

Follow-up of 882 patients with normal baseline fluoroscopy revealed incident overt CE in 95 leads (11%) after median risk time of 2.9 years, yielding an incidence rate of 4.9 (95% confidence interval [CI]: 3.9 to 5.9) per 100 patient-years. The incidence rate was significantly higher in 8-F Riata leads than in 7-F Riata ST leads (7.0 vs. 3.2 per 100 patient-years; p < 0.001). Electrical follow-up demonstrated electrical abnormality in 77 leads, resulting in an incidence rate of 4.0 (95% CI: 3.2 to 5.0) per 100 patient-years. The incidence rate of electrical abnormalities was not different between leads without CE and those with CE (3.9 vs. 5.2 per 100 patient-years; p = 0.39).

The development of CE is progressive in nature with an incidence rate of new CE of 4.9 per 100 patient-years, with a higher rate for 8-F Riata leads than for 7-F Riata ST leads. Despite the high rate of structural failure, no association between development of CE and electrical failure was observed.