Ambulatory ECG Recording in Mice

Summary

Telemetric ECG has emerged as an essential tool in evaluating animal models for cardiac arrhythmias and sudden cardiac death. Here, we present a stepwise guide to telemetric ECG recordings for application in long-term ambulatory ECG monitoring in mice.

Abstract

Telemetric ECG recording in mice is essential to understanding the mechanisms behind arrhythmias, conduction disorders, and sudden cardiac death. Although the surface ECG is utilized for short-term measurements of waveform intervals, it is not practical for long-term studies of heart rate variability or the capture of rare episodes of arrhythmias. Implantable ECG telemeters offer the advantages of simple surgical implantation, long-term recording of electrograms in ambulatory mice, and scalability with simultaneous recordings of multiple animals. Here, we present a step-by-step guide to the implantation of telemeters for ambulatory ECG recording in mice. Careful adherence to aseptic technique is required for favorable survival results with the possibility of implantation and recording from weeks to months. Thus, implantable ECG telemetry is a valuable tool for detection of critical information on cardiac electrophysiology in ambulatory animal models such as the mouse.

Protocol

1. Preparation of Telemeter for Surgical Implantation Before inserting an ECG telemeter into the mouse, it is important to make sure the ECG telemeter is sterile and in good working order. New telemetry devices are typically provided in a sterile condition by the manufacturer. ECG telemeters can be reused provided the device is cleaned using Tergazyme 1% solution for at least 4 hours. You may rinse the telemeter with sterile water after cleaning with Tergazyme. Additionally, use Wavicide-01 disinfect…

Discussion

The critical steps of this procedure are proper cleaning and preparation of the mouse prior to survival surgery. When a telemeter and the mouse operative site are properly cleaned, there is a much better post-surgical outcome. Additionally, close attention to lead placement reduces post-surgical skin erosion. Possible modifications to the technique include alternative configurations to evaluate lateral LV wall function (lead I configuration), or the use of the telemeter not only for ECG waveform analysis, but also for…

Materials

Material Name	Tipo	Company	Catalogue Number	Comment
Steri 250 Bead Sterilizer		Inotech	IS-250
Blunt-Ended Scissors		Roboz	RS-5980
Blunt-Ended Forceps (x2)		Roboz	RS-5138
Veterinary Anesthesia Vaporizer		Surgivet	Isotec 4
T/Pump		Gaymar	P/N11184-000
Propylene Blue Monofilament Suture		Ethicon	8718
Povodone Iodine, 10%		Equate	N/A
Alcohol Swabs		PDI	B339
Tergazyme		Alconox	21837-118
Wavidicde-01		Medical Chemical Corporation	Wavicide-01
ECG Telemeter		DataSciences International	EA-F20