Arrhythmias occur spontaneously in normal, healthy animals at a low incidence. Many arrhythmias are not harmful and have no clinical significance; however, some may have more serious effects and lead to cardiac arrest or sudden death. Changes in the incidence rate or type of arrhythmia may indicate disease progression or treatment effect. 

The tables below shows the most prevalent arrhythmias in the beagle dog and the cynomolgus monkey. Both the dog and the cynomolgus monkey can have prevalent occurrences of sinus rhythms to include bradycardia, tachycardia, sinus arrhythmia and premature ventricular complexes.  

Incidence/prevalence of spontaneous arrhythmia: beagle dog1

Arrhythmia Incidence Found Incidence Rate
Sinus rhythms (i.e. sinus rhythm, sinus arrhythmia, wandering sinus pacemaker, sinus arrest/block, sinus bradycardia, sinus tachycardia)
2450 100%
Ventricular premature complexes
4 0.16%
Second degree AV block
Bundle branch block (right)
Ventricular pre-excitation and Wolff-Parkinson-White syndrome

Incidence/prevalence of spontaneous arrhythmia: cynomolgus monkey1

Arrhythmia Incidence Found Incidence Rate
Sinus rhythms (i.e. sinus rhythm, sinus arrhythmia, wandering sinus pacemaker, sinus arrest/block, sinus bradycardia, sinus tachycardia)
1563 100%
Atrial premature complexes
2 0.12%
Ventricular premature complexes
Ventricular tachycardia
Ventricular bigeminy
1 0.06%
Bundle branch block (right)
11 0.7%
Ventricular escape rhythms
1 0.06%

Arrhythmias are identified by looking at an electrocardiogram (ECG) signal and assessing the rate and regularity of the heartbeat. Typically, ECG is measured by placing two electrodes directly on the skin and reading the potential difference between them. The detected waveform features depend on the amount of cardiac tissue involved in the contraction, and well as the orientation of the electrode placement with respect to the heart. A number of different ECG lead configurations exist based on electrode location and configuration.

The most common arrhythmia types1

Classification of Cardiac Arrhythmias
Normal sinus impulse formation
Normal sinus rhythm
Sinus arrhythmia
Wandering sinus pacemaker
Disturbances of sinus impulse formation
Sinus arrest/block
Sinus bradycardia
Sinus tachycardia
Disturbances of supraventricular impulse formation
Atrial premature complexes
Atrial tachycardia
Atrial flutter
Atrial fibrillation
Atrioventricular junctional rhythm
Ventricular premature complexes
Disturbances of ventricular impulse formation
Ventricular tachycardia
Ventricular asystole
Ventricular fibrillation
Sinoatrial block
Disturbances of impulse conduction
Persistent atrial standstill
Atrial standstill
Ventricular pre-excitation
First degree AV block
Second degree AV block
Complete AV block
Bundle branch block
Sick-sinus syndrome
Disturbances of both the impulse formation and impulse conduction
Ventricular pre-excitation and Wolff-Parkinson-White syndrome
Atrial premature complexes with aberrant ventricular conduction
Ventricular escape rhythms
Junctional escape rhythms
Ventricular escape rhythms

Arrhythmia Detection
Traditional arrhythmia detection is accomplished by examining ECG waveforms to assess heart rate and rhythm. Anomalies are found by manually counting the number of normal complexes (p waves for atrial rate, QRS for ventricular) in a given time period, looking for variations in waveform morphology, and marking missing waveforms. Previously developed software made only marginal improvements in the process.

Data Analysis Software

Data Insights™ offers an automated analysis method to accurately and consistently find, classify, and report on the arrhythmias within the ECG signal. The following table outlines the arrhythmia types, classifications, and quantification parameters available with Data Insights.

Types of Arrhythmias Classifications Reporting Parameters
Ventricular beats Runs of complexes Durations
Atrial beats Couplets Occurrences
Junctional beats Triplets Cycles per occurrence
Atrioventricular (AV) block Bigeminy Distribution
Sinus pause Trigeminy
Premature beats

Data insights screenshot
 DSI’s arrhythmia solutions offer flexibility, reliable performance, and quality to satisfy your research needs. 

DSI offers a variety of solutions for monitoring, analyzing and reporting arrhythmias in freely moving or restrained animal models. Implantable telemetryexternal telemetry, and hardwired methods are available for small to large animal models, offering you the ability to collect one or many physiologic signals. Each of DSI’s solutions for ECG research includes the necessary sensors, hardware, software, and accessories.





Data Acquisition and Analysis Software

DSI offers Ponemah™ software to help you facilitate acquisition of your ECG data. ECG PRO, a Ponemah analysis module, uses template-based analysis to select template cardiac cycles for precise comparison to other cycles in a dataset. Data Insights™, an add-on to Ponemah v5.20, was designed to automatically find, classify and report arrhythmias.




Scientific Services

DSI offers Technical Training Services to minimize the time it takes to set up and become proficient with our sophisticated ECG monitoring and analysis tools. DSI also offers Data Services—our team of experts can simplify your arrhythmia research by analyzing your data and accurately reporting the results.

PTD System Hardware






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DSI's bibliography search tool may help you find publications known to use DSI technology. It is searchable by keyword, title and author and references of interest can be easily exported. The following publications have been included as references to demonstrate how arrhythmias can be assessed and data applied to specific research applications.


Large Animal 

1Gauvin, D.V., Tilley, L. P., Smith, F. W. K. Jr., Theodore J. Baird. (2009). Spontaneous cardiac arrhythmias recorded in three experimentally- and drug-naive laboratory species (canine, primate, swine) during standard pre-study screening. Journal of Pharmacological and Toxicological Methods. 59(2) 57-61. doi: 10.1016/j.vascn.2008.12.001

Chui, R. W., Derakhchan, K. & Vargas, H. M. (2012). Comprehensive analysis of cardiac arrhythmias in telemetered cynomolgus monkeys over a 6 month period. Journal of Pharmacological and Toxicological Methods. 66(2):84-91. doi: 10.1016/j.vascn.2012.05.002

Cools, F., & Gallacher, D. (2009). Normal prevalence of cardiac arrhythmias in 24 h ECG recordings of chronically telemetered, healthy, freely moving beagle dogs. Journal of Pharmacological and Toxicological Methods, 60(2), 235–236. http://doi.org/10.1016/j.vascn.2009.04.112

Tilley, L. P., Smith, F. W. K., Oyama, M. A., & Sleeper, M. M. (2008). Manual of Canine and Feline Cardiology (Fourth Edition). Elsevier.