[The effect of age and training on the ECG time curve of purebred horses].

The study observed the impacts of aging and training on the heart activity (ECG – Electrocardiogram) of English Thoroughbred horses. The researchers found that with increasing age and extensive training, the heart action slowed down gradually, characterizing the origin of sports ECG in trained racehorses.

Study Participants

• The research was conducted on 246 English Thoroughbred horses of varying age groups.
• The horses were divided into four distinct test populations for a comprehensive comparison.

Observation Metrics

• The researchers studied the effects of age and training on the pulse rate of horses.
• Time intervals of several ECG components were also observed – PQ (Atrioventricular conduction time), QRS (Ventricular depolarization), QT (Total duration of electrical activity in the heart’s lower chambers), and QTc (Corrected QT interval that adjusts the QT interval for heart rate).

Findings

• The researchers noted that with increasing age and more intense training, the heart action of horses slowed down progressively.
• Specifically, the time duration for the atrioventricular path (PQ interval) was prolonged as the horses aged and underwent more training.
• Similarly, the time of ventricular activation (QRS interval) and the time of the electrical systole (QT and QTc intervals) also exhibited an increase, indicating slower heart action.

Significance of the Study

• Through the research, the scientists could characterize the origin of the so-called sports electrocardiogram in trained racehorses. This is a specific kind of ECG pattern often found in athlete horses due to their intense physical training and performance.
• The findings from this research can be beneficial for further studies focusing on maintaining the cardiovascular health of sports horses or investigating cardiac conditions in equine athletics.