Use of an Implantable Loop Recorder in a Chimpanzee (Pan troglodytes) to Monitor Cardiac Arrhythmias and Assess the Effects of Acupuncture and Laser Therapy

Abstract

Cardiovascular disease is a leading cause of death in captive chimpanzees and is often associated with myocardial fibrosis, which increases the risk of cardiac arrhythmias. In this case report, we present a 36-y-old male chimpanzee (Pan troglodytes) diagnosed with frequent ventricular premature complexes (VPC). We placed a subcutaneous implantable loop recorder for continual ECG monitoring to assess his arrhythmias without the confounding effects of anesthetics. During his initial treatment with the antiarrhythmia medication amiodarone, he developed thrombocytopenia, and the drug was discontinued. After reviewing other potential therapies for the treatment of cardiac arrhythmias, we elected to try acupuncture and laser therapy in view of the positive results and the lack of adverse side effects reported in humans. We used 2 well-known cardiac acupuncture sites on the wrist, PC6 (pericardium 6) and HT7 (heart 7), and evaluated the results of the therapy by using the ECG recordings from the implantable loop recorder. Although periodic increases in the animal's excitement level introduced confounding variables that caused some variation in the data, acupuncture and laser therapy appeared to decrease the mean number of VPC/min in this chimpanzee.

Figure 1.

ECG strip (3-lead) from January 2012, demonstrating couplet VPC (arrows).

Figure 2.

Implantable loop recorder placed subcutaneously between shoulder blades.

Figure 3.

Male chimpanzee presenting his back for downloading of ECG data stored on the implantable loop recorder.

Figure 4.

ECG from the implantable loop recorder, demonstrating the presence of VPC (arrows).

Figure 5.

Adult male chimpanzee receiving acupuncture and laser therapy at acupuncture sites PC6 and HT7.

Figure 6.

The frequency (mean ± 1 SD) of VPC during amiodarone treatment and after acupuncture and laser therapy.