A survey of the frequency and development of heart disease in riding-horses - Part 1: retrospective evaluation (92 - 03) and questionnaires

Abstract

In this study first of all the frequency of various heart diseases in 555 horses was examined over a period of eleven years (4.1 years). The most frequently occurring disease was mitral valve insufficiency, either isolated (n = 132; 24%) or combined with another valve insufficiency (n = 102; 18%). 37 (28%) of the 132 horses with mitral valve insufficiency had a dilated left atrium of more than 13.5 cm at the time of the first examination, 38 horses (7%) showed an isolated, and 45 horses a combined aortic valve insufficiency. 25 horses (5%) had a tricuspid valve insufficiency. 77 horses (14%) showed a tricuspid valve insufficiency accompanied by another valve insufficiency. 42 horses (8%) had regurgitations at more than two valves. 174 of the 555 horses (31%) had a cardiac arrhythmia (atrial fibrillation n: = 133, atrial extra systoles: n = 30, ventricular extra systoles: n = 11). 46 of the 555 horses were euthanatized immidiatly after the examination or after attempted therapy because of a poor prognosis. Of the remaining 509 owners the addresses of 478 were ascertained and these received a questionnaire inquiring about use and symptoms of disease in their horses. 38% of these questionnaires were returned. Although 59% of the horses were described by their owners as free from health problems at the time of the first examination, but only 31% at the time of answering the questionnaires, nevertheless 55% of the owners used their horses after the first cardiological diagnosis on the same level of sport as before the heart disease was discovered. 4% used their horses more intensively in equestrian sport and in the case of the other horses (41%) the demands were reduced. Of the 182 horses 20% showed a perceptible loss of performance, 15 % of the 182 horses were euthanatized at various intervals after the first cardiological examination because of the heart disease. A connection between duration, type and severity of heart disease and length of survival could not be proved.