Two digital electrocardiographs and their computer-based analysis programs produce clinically significant differences...

Area of Science:

• Veterinary Cardiology
• Biomedical Engineering
• Canine Physiology

Background:

• Electrocardiography (ECG) is crucial for assessing canine cardiac health.
• Establishing accurate reference intervals for ECG parameters in athletic dogs is essential for proper diagnosis.
• Differences in electrocardiograph (ECG) technology may influence measured values.

Purpose of the Study:

• To compare ECG measurements between veterinary and human electrocardiographs in endurance-trained dogs.
• To develop specific ECG reference intervals for this canine population.
• To identify how device characteristics affect ECG readings.

Main Methods:

• Simultaneous standard limb lead ECG recordings were obtained from 121 endurance-trained dogs using two digital electrocardiographs (veterinary and human).
• Computer-based ECG measurements were compared using statistical tests (Wilcoxon signed-rank, Deming regression) and Bland-Altman plots.
• Predefined acceptable median differences (effect sizes) were used to assess clinical significance.

Main Results:

• Significant differences were found in most global ECG indices and lead amplitudes between the two electrocardiographs.
• The veterinary ECG showed higher Q- and R-wave amplitudes (11-23%) in leads II and III.
• The veterinary ECG identified more dogs with potential ventricular enlargement and produced narrower reference intervals for most indices.

Conclusions:

• Veterinary and human electrocardiographs produce different ECG measurements in endurance-trained dogs.
• The low-pass filter characteristics of the veterinary ECG contribute to observed differences.
• Accurate canine ECG reference intervals are dependent on the specific electrocardiograph, its filtering, and analysis software.