Open AccessFactors Affecting Prognosis and Conversion in Equine Atrial Fibrillation
Author(s) -
Reef Virginia B.,
Levitan Chelsie W.,
Spencer Pamela A.
Publication year - 1988
Publication title -
journal of veterinary internal medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.356
H-Index - 103
eISSN - 1939-1676
pISSN - 0891-6640
DOI - 10.1111/j.1939-1676.1988.tb01970.x
Subject(s) - medicine , heart failure , horse , atrial fibrillation , cardiology , sinus rhythm , digoxin , regurgitation (circulation) , quinidine , mitral regurgitation , sinus tachycardia , heart disease , paleontology , biology
Sixty‐seven horses presented with atrial fibrillation (AF) from January I, 1980 to August 1, 1986. All horses were evaluated for the type and severity of the underlying cardiac disease and the probable duration of the arrhythmia. Fifty‐two (78%) of the horses were treated with quinidine sulfate and/or digoxin. The response to treatment was assessed in each horse. Horses were followed for periods extending from 8 months to 7 years. Standardbreds, young horses, and males predominated in the study group. There were more male horses (stallions and geldings) than mares. Most horses with AF had no evidence of other cardiac disease (56.7%). All performance horses without other cardiac disease were treated, and return to performance was significantly associated with conversion to sinus rhythm. Horses that did not convert with quinidine sulfate therapy, whose arrhythmia recurred, and that had side effects from quinidine sulfate therapy, had a longer history of poor performance. Tachycardia (heart rate > 60 beats/min) was significantly associated with the existence of congestive heart failure. The horses with congestive heart failure had a poor prognosis for life (7.7% survived) and a poor conversion to normal sinus rhythm (23.1 %). Mitral regurgitation (19 horses) was the most common underlying cardiac disease. Tricuspid regurgitation (15 horses), aortic regurgitation (3 horses), myocardial dysfunction (3 horses), and atrial septal defect (1 horse) also were diagnosed. Congestive heart failure was common in this group of horses with underlying cardiac disease.