A new electrocardiogram (ECG) recording technique can quickly detect a difficult to diagnose heart condition, paroxysmal atrial fibrillation (PAF), which can be fatal in horses. This condition is also a major cause of stroke in humans.
In a study published in the journal Nature Scientific Reports, researchers from the University of Surrey detail how they developed a rapid and inexpensive technique to identify PAF, a condition that causes rapid, erratic heart beats in horses. Due to the intermittent nature of the condition it is often difficult to diagnose and can impact on a horse’s racing performance and in some cases can be fatal.
In humans, this arrhythmia can be very dangerous as it can cause disruption of blood flow in the upper two chambers of the heart, which could lead to the formation of blood clots in the organ. Such clots could block blood vessels elsewhere in the body, including the brain, resulting in cognitive decline and ischaemic strokes.
During the study, ECG recordings were obtained during routine clinical work from healthy horses and those with a diagnosis of PAF. ECG traces with no other electrical disturbances were converted to a string of computational numbers using a range of detection algorithms. It was found that ECG results, recorded at rest (low heart rate of 25–60 bpm) and processed by the novel detection method, were found to be significantly different between horses with and without PAF. This allowed identification of horses with PAF from sinus-rhythm ECGs with high accuracy.
Timely detection of PAF is crucial for effective treatment of the condition. Electrical stimulation or antiarrhythmic drugs could restore the normal heart rhythm and anti-coagulation drugs might prevent formation of blood clots preventing strokes or greatly reducing their consequences.
Leader author of the study Dr Vadim Alexeenko, a Research Fellow at the School of Veterinary Medicine at the University of Surrey, said: “I am very happy to see that in horses we obtained such excellent results and came up with a tool which could be easily used even by a non-professional. It was also very exciting to devise the new approach of ECG parsing, which is absolutely essential for high sensitivity and specificity of our method”.
Head of this research team, Dr Kamalan Jeevaratnam, said: “The fascinating aspect of this study is that we are looking at the arrhythmia which typically is provoked by high heart rate, but we diagnose it looking at low heart rate recordings. There is no need to exercise the horse and the analysis could be done in minutes, using low power computers. As a clinician, I think such analysis will greatly facilitate detection of this arrhythmia and it will promote the use of ECG by my colleagues.”
In line with the University of Surrey’s One Health agenda, Dr Jeevaratnam is now in discussion with several other groups based elsewhere in the UK and US to move this exciting piece of work into human studies whilst in parallel exploring the potential of partnering with device companies in the equine industry. This study was funded by the PetPlan Charitable Trust.
