Evaluation of a novel ambulatory electrocardiogram monitor (the Carnation Ambulatory Monitor) for use in horses

Comparison of the diagnostic value of a small, single channel, electrocardiogram monitoring patch with a standard 3-lead Holter system over 24 h in dogs

INTRODUCTION/OBJECTIVES

The aim of this study was to compare a novel small event recorder device, the Carnation Ambulatory Monitor (CAM), with a standard Holter.

ANIMALS

Nineteen adult dogs.

MATERIAL AND METHODS

Comparative and explorative study. The two devices were simultaneously applied for approximately 24 h.

RESULTS

analysis time (p=0.013) and percentage of artefacts (p<0.001) were greater for the CAM (110 min [40-264]; and 9% [0-34], respectively) compared to a standard Holter (30 min [18-270]; and 0.3% [0-9], respectively). The total number of beats (p=0.017) and maximum (p=0.02) and mean (p=0.037) heart rates were lower for the CAM (113,806 ± 23,619 beats; 227 ± 35 bpm; and 88 ± 22 bpm, respectively) compared to the standard Holter (131,640 ± 40,037 beats; 260 ± 64 bpm; and 92 ± 26 bpm, respectively). The minimal heart rate (p=0.725), number of pauses (p=0.078), duration of the longest pause (p=0.087), number of ventricular ectopic beats (p=0.55), ventricular couplets (p=0.186), ventricular triplets (p=0.203), ventricular tachycardia (p=0.05), Lown grade (p=0.233), presence or absence of ventricular bigeminy, trigeminy, supraventricular tachycardia, and atrial fibrillation (p=0.98) did not differ. The CAM missed some relevant events, like complex ventricular arrhythmias, and the Lown grade did not match in 5/19 dogs when comparing the devices.

CONCLUSIONS

CAM can be used to record ECG traces in dogs over a prolonged period, allowing to detect arrhythmias. Due to some clinically relevant limitations, including a higher percentage of artefacts, a longer reading time (which precludes quantitative counts of >300VPCs), and underestimation of complex ventricular arrhythmias, the CAM appears not suitable for quantitative arrhythmia analysis in dogs.

Paroxysmal Atrial Fibrillation in Horses: Pathophysiology, Diagnostics and Clinical Aspects

Atrial fibrillation (AF) is the most common arrhythmia in horses causing poor performance. As in humans, the condition can be intermittent in nature, known as paroxysmal atrial fibrillation (pAF). This review covers the literature relating to pAF in horses and includes references to the human literature to compare pathophysiology, clinical presentation, diagnostic tools and treatment. The arrhythmia is diagnosed by auscultation and electrocardiography (ECG), and clinical signs can vary from sudden loss of racing performance to reduced fitness or no signs at all. If left untreated, pAF may promote electrical, functional and structural remodeling of the myocardium, thus creating a substrate that is able to maintain the arrhythmia, which over time may progress into permanent AF. Long-term ECG monitoring is essential for diagnosing the condition and fully understanding the duration and frequency of pAF episodes. The potential to adapt human cardiac monitoring systems and computational ECG analysis is therefore of interest and may benefit future diagnostic tools in equine medicine.