Regional results of the lead evaluation for defibrillation and reliability (LEADR) trial
Authors: Mason P , Sanders P , Hansky B , De Filippo P , Shah M , Shoda M , St Martin A , Crossley G 
Published: October 2024

Abstract

Introduction
ICD/CRT-D patients are living longer, and interest in reliable leads with targeted placement is growing. The Lead EvaluAtion for Defibrillation and Reliability (LEADR) trial was designed to assess the novel small-diameter, lumenless, catheter-delivered, defibrillation study lead. The study lead is based on the SelectSecure SureScan MRI Model 3830 lumenless pacing lead delivered by catheter that has a simplified durable construction with improved long-term reliability (97.2% 12-year RV lead survival).

Purpose
The LEADR trial assessed the efficacy and safety of the novel defibrillation lead.

Methods
The global LEADR Pivotal trial (NCT04863664) enrolled patients with ACC/AHA/ESC guideline-directed indications for de novo implant of a primary or secondary prevention ICD/CRT-D. The primary efficacy and safety endpoints were defibrillation success at implant and freedom from study lead-related major complications at 6-months, respectively.

Results
A total of 643 patients were successfully implanted (61.9±12.9 years, 26% female, 28.5±6.4 kg/m2 BMI, and 80.9% NYHA Class II) with the study lead placed in the desired RV location in 99.5%. The estimated freedom from study lead-related major complications was 97.1% at 6- and 12-months. Defibrillation testing was successful in 116/119 (97.5%) patients. The prespecified primary efficacy and safety thresholds (88% and 90%, respectively) were exceeded. There were zero study lead fractures and electrical measurements were stable through 12.7±4.8-month mean follow-up.
Approximately 20% of patients were in Asia, 9% in Australia, 21% in Europe, and 50% in North America (Table). The estimated freedom from study lead-related major complications at 6- and 12-months per region were 96.2% in Asia, 100% in Australia, 96.4% in Europe, and 97.2% in North America (Figure), P=0.82 across regions. There were 19 study lead-related major complications (5 in Asia, 0 in Australia, 5 in Europe, 9 in North America), with the most common being lead dislodgement across regions. Defibrillation testing was successful in 116/119 patients with 33/33 in Asia, 32/32 in Australia, 7/8 in Europe, and 44/46 in North America, P=0.11 across regions. Among the 3 patients with unsuccessful testing, 2 (North America) remained in the study at physician discretion after successful conversion outside of protocol requirements, and 1 (Europe) was exited. Pacing capture threshold, pacing impedance, and R-wave amplitude were chronically stable across regions.

Conclusion
The LEADR Pivotal trial demonstrated the safety, efficacy, and reliability of the novel defibrillation lead, exceeding prespecified efficacy and safety thresholds. There were no notable differences in primary endpoints between regions. The trial has met its endpoints and ongoing follow-up will provide long-term performance. This trial demonstrated the ability to place the lead in targeted RV locations; a study of this lead for conduction system pacing is forthcoming.TableFigure