Arrhythmogenic right ventricular cardiomyopathy as a cause of unexpected cardiac death in two horses.

This research article investigates the unexpected deaths of two mature horses, which were found to have a heart condition known as arrhythmogenic right ventricular cardiomyopathy, following postmortem examination.

Introduction to the Condition

• The research study focused on a condition called arrhythmogenic right ventricular cardiomyopathy (ARVC).
• ARVC is a type of heart disease that primarily affects the right ventricle of the heart.
• This disease involves the replacement of myocardium, or heart muscle, with fibrous and fatty tissues, disrupting the normal heart rhythm.

Postmortem Examination

• Following the unexpected deaths of two horses, a postmortem examination was conducted to determine the cause.
• The horses in question were a five-year-old Clydesdale gelding and a 15-year-old cob gelding.
• During the examination, gross pathological changes were found, notably, the right ventricular endocardium and interventricular septum of the horses’ hearts were largely replaced with a gelatinous yellow fibroareolar tissue.

Histological Findings

• A histological examination of the changes further confirmed the presence of ARVC.
• The tissue that had replaced the normal myofibres in the right ventricle was found to be a combination of fibrous and fatty, or adipose, tissue.
• This is typical of ARVC, as these tissues disrupt normal cardiac function by replacing the myocardium and interrupting the function of the Purkinje fibres which are crucial for maintaining a healthy and stable heart rhythm.
• The disruption of these fibres can lead to a range of cardiac abnormalities, including failure of the right side of the heart, arrhythmias and, ultimately, sudden death.

Conclusion

• Through gross postmortem and histological examination, the study concluded that the unexpected deaths of both geldings were caused by ARVC.
• These findings highlight the possible presence and impact of this condition within the equine community, calling for more research and awareness about its prevalence and effects among horses.