Development of an experimental method for long-term electrocardiographic recordings in a heart failure rabbit model

A method has been developed where the electrocardiogram (ECG) is monitored continuously using implantable monitors in a doxorubicin rabbit model of heart failure. The primary goal is to devise strategies to detect and analyze changes in the ECG as the disease develops. Doxorubicin was injected weekly in four rabbits at two different doses, 2 mg/kg and 4 mg/kg per week. Two control rabbits received saline injections. The ECG was continuously tracked and recorded (1000 samples per sec) for three control and up to ten treatment weeks. Data was produced 180 MB per ECG channel per day per rabbit, totaling around 200 GB for the study. Eleven classic heart rate variability (HRV) parameters were derived for every usable 5-minute segment for the entire period of the recordings. A new visualization technique was designed The results graphically show changes in the circadian rhythm in treatment group with a general loss in circadian rhythm and decrease in HRV.