Canadian Registry of Implantable Electronic Device Outcomes

Abstract

Background— The Riata lead under advisory has posed a unique clinical scenario where inside-out abrasion results in externalization of conductor cables, with a higher risk of electrical failure. We developed a comprehensive registry to assist with clinical management of this lead. Methods and Results— This Canadian registry reports the findings of 3763 (74.2% of all Riata leads in Canada) Riata leads under advisory, with a mean follow-up time of 8.9±1.5 years. The overall electrical failure rate was 5.2% at 8 years, with no difference between 7-French and 8-French lead models. Cable externalization was found to be more common in the 8-French model (12.3% versus 5.2%, P <0.0001) and was associated with a higher risk of electrical failure. Predictors of electrical lead failure included cable externalization, higher left ventricular ejection fraction, younger age, higher body mass index, and a passive fixation lead. One patient died due to electrical failure, a further 2 patients survived an event where the device failed to deliver high-voltage therapy. Major complications because of lead extraction were higher when compared with lead abandonment, no difference among lead model observed. Two deaths occurred as a consequence of lead extraction, in the context of an underlying infection. Conclusions— The Riata lead under advisory has a steady electrical failure rate over time. There are identifiable predictors of lead failure that can assist with clinical decisions as to whether lead revision should be performed prophylactically.

Failure-free survival of the Riata implantable cardioverter-defibrillator lead after a very long-term follow-up

“…Although the cumulative incidence of EF was similar to previous studies at 8 years (4% in our cohort vs. 5.2% in the registry of Parkash et al. [5]), during the complete follow-up it rose to 20%. On the other hand, over the whole follow-up period the 14% CE rate was within the lower range of previous studies (11%–43%) [6] but was only 2% at eight years.…”

“…In 2011, the United States Food and Drug Administration (FDA) issued a class I advisory for the Riata and Riata ST ICD leads [3]. This advisory described design problems in silicone-coated Riata leads, resulting in conductor cable externalization (CE) [4,5]. An increased rate of electrical failure (EF) also has been observed [4].…”

“…Although most observational studies have demonstrated a significantly increased rate of EF in the setting of CE (between 3 and 6 times higher when CE was present, compared to leads without externalization), this specific association remains unclear [4,6,7]. The use of routine radiographic screening for CE has accordingly been questioned, in particular because the incidence of EF without externalization is not trivial and lead revision (and especially lead extraction) has been associated with a higher rate of major complications [4,5].…”

“…Several studies have focused on the short-term performance of the Riata ICD lead; however, only two studies [5,12] have investigated the associated long-term complications, with a mean follow-up duration of 8.9 and 7 years, respectively.…”

Inside-out abrasion and contained conductor cable externalization in a defibrillation lead with asymmetric conductor cable lumen distribution

“…Inside-out abrasion (IOA) is a distinct mode of insulation damage caused by conductor cables moving relative to the lead body, and may result in conductor cable externalization (CCE) and electric malfunction. 1 , 2 , 3 IOA/CCE mainly affects defibrillation (DF) leads and has so far been observed only in models with symmetric conductor cable lumen distribution—the Riata 1 , 2 and Durata 4 , 5 leads by St Jude Medical/Abbott (Sylmar, CA) and the Kentrox 6 , 7 and Linox 8 leads by Biotronik (Berlin, Germany). This report describes the first case of IOA/CCE in a DF lead with asymmetric conductor cable lumen distribution: the Sprint Quattro Secure lead by Medtronic (Minneapolis, MN).…”