Learning From Implantable Cardioverter-Defibrillator Leads in Children

If you want to break something, give it to your kid. That truism applies to many items from toys to technology. The paper describing the results of the PLEASE study (Pediatric Lead Extractability and Survival Evaluation Study) from Berul et al in this issue of Circulation provides sobering but important evidence that this also applies to implantable cardioverter-defibrillator (ICD) leads.1 Most ICD systems are implanted in adults, but many are implanted in children. These pediatric patients with ICD systems now participate in larger ICD registries,2 but an earlier specific pediatric registry is the target of this study. This study encompasses 874 patients and 965 ICD leads, spanning 24 centers. The initial ~1/5th of the patients were enrolled in a randomized study comparing two specific lead designs: the smaller Medtronic Fidelis lead, and a larger but ePTFE coated Boston Scientific alternative. This portion of the study was terminated when concerns about Fidelis lead performance surfaced, and these and all subsequent patients entered into a registry, with more patients and nearly inclusive entry for the latter portion of the enrollment. Although not pre-specified, I think this flexibility was laudatory, allowing the salvage of useful and generalizable information, and does not appear to be an obvious source of bias or scientific compromise. The study design however is essentially that of a registry rather than a randomized study.