CARDIAC ASSESSMENTS AND IMPLANTABLE LOOP RECORDER PLACEMENT IN THREE MALE GELADAS (THEROPITHECUS GELADA)

Area of Science:

• Veterinary Cardiology
• Primate Medicine
• Zoological Wildlife Health

Background:

• Cardiac disease is a significant cause of mortality in zoo-housed primates.
• Ten cases of sudden cardiac death occurred in adult male geladas at the Bronx Zoo between 2007 and 2018, with no preceding symptoms.
• Occult cardiac disease and fatal arrhythmias are a concern in this species.

Purpose of the Study:

• To conduct comprehensive cardiac evaluations in clinically normal, adult male geladas.
• To investigate the utility of implantable loop recorders for diagnosing cardiac abnormalities in primates.
• To explore potential mechanisms behind sudden cardiac death in geladas.

Main Methods:

• Performed thoracic radiographs, transthoracic echocardiograms (echo), and 12-lead electrocardiograms (ECG) on three geladas.
• Utilized continuous ECG monitoring with implantable loop recorders for up to 2.5 years.
• Assessed serum lipid profiles, vitamin E, cardiac troponin I isoform (cTnI), and complete blood work.

Main Results:

• One gelada exhibited an elevated cTnI level, reduced ejection fraction (46%), and documented supraventricular and non-sustained ventricular tachycardias.
• This individual was treated with metoprolol and lisinopril for nearly two years.
• The treated gelada experienced sudden cardiac death due to sustained ventricular fibrillation, confirmed by postmortem loop recorder data and histology showing cardiomyopathy.

Conclusions:

• Implantable loop recorders are valuable tools for diagnosing and managing arrhythmias in primates.
• This study highlights the potential for cardiomyopathy and fatal arrhythmias in geladas.
• Further research is needed to establish species-specific reference ranges for cardiac diagnostics and develop treatment protocols.