Jacketed Telemetry with Integrated ECG electrodes: A Comparison with Traditional Implants in Beagle Dogs
FARES Raafat1, BENDRIMIA Anes1, BOUARD Delphine1, CAMBIER Agathe2, NADJAR Clémence2, EYNARD Charles2, FLENET Timothé2, Pascal CHAMPEROUX1
1ERBC Chemin de Montifault, 18800 Baugy, France
2R&D Department, ETISENSE, Lyon, RHONE, France
Abstract
Jacket telemetry technology enables the collection of both qualitative and quantitative ECG interval data in routine repeat-dose toxicology studies. The ICH M3(R2) guideline Q&As emphasize that integrated safety pharmacology assessments should maintain a level of rigor comparable to stand-alone safety pharmacology studies. However, unlike implanted telemetry, jacket-based ECG electrodes are more prone to displacement or disconnection, especially in socially housed animals such as monkeys and dogs, which can compromise data quality.
To address these challenges, the Decro jacket—previously validated as a reliable platform for integrating safety pharmacology endpoints in dog toxicology studies—was completely redesigned and upgraded to include integrated 3D ECG electrodes embedded within the jacket. The new design features an adjustable, single-layer soft and stretchable jacket with integrated 3D ECG electrode patches, eliminating the need to shave or trim the animals’ fur.
Our study aimed to evaluate the performance of this new system by comparing its signal quality to that of invasive telemetry in six group-housed Beagle dogs.
Dogs received vehicle control, quinidine (30 mg/kg), or ivabradine (2 mg/kg) orally according to a Latin square design. To ensure objective comparison, data from both systems were analyzed using a specialized software developed in RPL (RS/1 programming language). Ventricular repolarization was assessed with QT intervals corrected by the probabilistic method and the one-step QTc model. Drug effects on autonomic control were quantified using the High Frequency Autonomic Modulation (HFAM) model known to be highly sensitive to overall ECG quality signal. Beat-to-beat analysis was fully automated.
Across four 8-hour recording sessions per dog, the jacket showed no damage or adverse interactions, indicating robust design and excellent animal acceptance. High-quality lead II ECG signals were consistently obtained despite intact hair. Mean predose heart rate, PQ, PR, QRS, and QT intervals showed no or minimal differences between jacketed and implanted telemetry. Pharmacological responses to quinidine and ivabradine were reliably detected by both systems, with identical results.
This upgraded jacket telemetry system overcomes traditional limitations by providing sensitive, high-quality ECG data with improved animal welfare, making it a valuable tool for safety pharmacology assessment in toxicology studies involving conscious dogs.
