Atrial Fibrillation in the Horse

Holmes, J. R.; Darke, P. G. G.; Else, R. W.

doi:10.1111/j.2042-3306.1969.tb03375.x

Cited by 40 publications

(23 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Bergsten (1974) used the same method of exercise to examine horses with lung disease. Holmes, Darke and Else (1969) and Deegen (1971) measured the exercising heart rates of horses with atrial fibrillation. More recently, research on exercising heart rates in horses with heart disease has been presented by Hall, Steel and Stewart (1976) and in horses with lung disease by Littlejohn,Kruger and Bowles ( I 977).…”

Section: Introductionmentioning

confidence: 99%

Heart Rate during a defined Exercise Test in Horses with Heart and Lung Diseases

Maier-Bock

Ehrlein

1978

Equine Veterinary Journal

View full text Add to dashboard Cite

SUMMARY During a gradually increasing exercise test heart rates were determined in healthy animals and in 2 groups of sick horses. These included 31 animals with a chronic pulmonary disorder and 5 with chronic heart disease. The alteration in heart rate was correlated with the clinical signs exhibited. In the horses with lung disease there was a close correlation between the stage of the disease and the heart rate during the exercise test. In 3 animals with heart valve disease there was no apparent difference in heart rate compared with healthy horses. On the other hand the exercising heart rate of horses with atrial fibrillation showed a significant increase. The recovery rate of pulse and respiration after a 20 min trot did not show any correlation with the stage of disease or the results of gradually stepping up the exercise in horses with lung disease. RÉSUMÉ Durant un exercice graduellement accru le rythme du coeur a été déterminé chez des chevaux sains et chez des chevaux malades. Parmi ceux ci 31 animaux souffraient d'une affection pulmonaire chronique et 5 d'une maladie cardiaque chronique. L'alteration du rythme cardiaque était en relation avec des signes cliniques. Chez les chevaux atteints d'une affection pulmonaire il est apparu une étroite correlation entre le degré de l'affection et le rythme du coeur durant l'exercice. Chez les chevaux présentant une affection valvulaire cardiaque le rythme ne fut au contraire point different de celui constaté chez des animaux sains. Par contre les chevaux atteints de fibrillation auriculaire montràrent dans les mêmes conditions un accroissement appreciable de leur rythme cardiaque. La rapidité de récupération du pouls et de la respiration apràs 20 min de trot ne montra point l'existence d'une correlation avec le degré de l'affection. ZUSAMMENFASSUNG Während einer graduell gesteigerten Belastung wurde die Herzschlagfrequenz bei gesunden Pferden und bei zwei Gruppen kranker Tiere bestimmt. Die Gruppen umfassten 31 Pferde mit chronischen Lungenleiden, 5 Tiere mit chronischen Herzkrankheiten. Die Veränderungen der Frequenz wurde mit den klinischen Symptomen korreliert. Bei Pferden mit Lungenleiden bestand eine enge Beziehung zwischen Krankheitsstadium und Herzfrequenz während der Belastung. Pferde mit Klappenerkrankungen wiesen keine Frequenzunterschiede zu gesunden Tieren auf. Im Gegensatz dazu zeigten Patienten mit Vorhofflattern unter Belastung eine signifikante Frequenzzunahme. Die Erholungsfrequenz von Herz und Atmung nach 20 Minuten Trab liess sich nicht mit dem Krankheitsstadium korrelieren, ebensowenig wie mit den Resultaten zunehmender Belastung von lungenkranken Pferden.

show abstract

Section: Introductionmentioning

confidence: 99%

Heart Rate during a defined Exercise Test in Horses with Heart and Lung Diseases

Maier-Bock

Ehrlein

1978

Equine Veterinary Journal

View full text Add to dashboard Cite

show abstract

“…The only abnormality demonstrated in the ECG was AF. It cannot be excluded that the co-existence of AF obscured recognition of this phenomenon (12). To what extent baroreceptor responses contribute to alterations in the electrophysiological behaviour of the atrioventricular node caused by autonomous nervous influences on atrioventricular conduction, and therefore to the slow heart rate, remains unclear (1, 3,20).…”

Section: Discussionmentioning

confidence: 99%

“…Myocardial disease is characterized by a reduced myocardial contractility and is associated with congestive heart failure (CHF) and arrhythmias including atrial fibrillation (AF) (12,21,23,24,26). Systemic factors involved in the development of myocardial disease are viral or bacterial infections, electrolyte disturbances, hypoxia, septicaemia, (endo-)toxaemia, monensin intoxication, lymphosarcoma, and severe metabolic derangements (5,21,23,29).…”

Section: Introductionmentioning

confidence: 99%

“…Myocardial disease accompanied by eccentric hypertrophy can result in annular valve dilatation and atrioventricular valve incompetence, which further increases the atrial enlargement (10,26), increasing the risk of AF (10). Two categories of AF can be distinguished in horses, namely, AF occurring without underlying cardiac disease and AF occur-ring secondary to or in relation with heart disease (3,6,7,12,19,24). The first type is most frequently seen in racehorses of racing age, showing signs of exercise intolerance.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Atrial fibrillation associated with central nervous symptoms and colic in a horse: A case of equine cardiomyopathy

Wijnberg

Kolk

Garderen

et al. 1998

Veterinary Quarterly

View full text Add to dashboard Cite

SUMMARYA 18-year-old Dutch Warmblood mare was referred for colic. Upon arrival, lethargy, blindness, head pressing, ataxia, and circling were the main clinical signs. On rectal examination a hard mass and oedema around the cranial mesenteric artery were palpated. Plasma liver enzyme activities and the ammonia level were elevated. Atrial fibrillation with a pulse frequency of 36-52 beats per minute was noticed. On both sides a holosystolic murmer with the maximum intensity on the right side could be auscultated. Postmortem examination revealed eccentric hypertrophy of the right atrium and a pale spotted myocardium, most prominently of the right ventricle, with secondary venous congestion of the azygos and mesenteric veins. The liver changes were indicative of chronic congestion. Despite the normal pulse rate, it appeared that congestive heart failure due to cardiomyopathy, was responsible for the presenting symptoms of this patient.

show abstract

“…Bei Hunden kann die Rhythmusstörung dagegen leicht provoziert werden, ist allerdings meist von nur kurzer Dauer [4]. Pferde schließlich entwickeln spontan Vorhofflimmern, welches für lange Zeit persistieren kann [16]. Bei primär kleinem Vorhof erhöht eine sekundäre Größenzunahme im Rahmen unterschiedlicher Krankheitsprozesse ebenfalls die Anfäl-ligkeit für persistierendes Vorhofflimmern.…”

Section: Introductionunclassified

Vorhofflimmern: Pathophysiologie

Schoels

Bauer²,

Becker³

et al. 2002

Herz

View full text Add to dashboard Cite

Based on the findings of Garrey and of Moe & Abildskov, atrial fibrillation has long been considered as the prototype of an arrhythmia being caused by multiple, random reentrant circuits, the number of which would determine the stability of the reentrant process. Local refractory and conduction properties would determine the size of individual circuits, a hypothesis quite convincing with respect to refractoriness, but so far hard to prove with respect to conduction. The finding that rapid atrial rates shorten atrial refractory periods and reverse rate adaptation (atrial remodeling) has coined the phrase "atrial fibrillation begets atrial fibrillation", indicating that any atrial tachyarrhythmia modifies the substrate in a way that favors reentry. With intracellular calcium overload being the initial trigger, down-regulation of genes encoding for calcium channels seems to primarily account for atrial remodeling. Primarily neglected concepts on the pathophysiology of atrial fibrillation suggesting single, meandering circuits or focal activity have regained attention. Atrial fibrillation as a random phenomenon is questioned not only by the dominant role of the left atrium for the maintenance of the arrhythmia, but also by most recent data demonstrating a spatio-temporal periodicity in activation patterns. Finally, ablation studies have provided convincing evidence that there is a subset of patients with focal or at least focally induced atrial fibrillation.

show abstract

Atrial Fibrillation in the Horse

Cited by 40 publications

References 15 publications

Heart Rate during a defined Exercise Test in Horses with Heart and Lung Diseases

Heart Rate during a defined Exercise Test in Horses with Heart and Lung Diseases

Atrial fibrillation associated with central nervous symptoms and colic in a horse: A case of equine cardiomyopathy

Vorhofflimmern: Pathophysiologie

Contact Info

Product

Resources

About