Abstract :
[en] Risk factors for valvular regurgitations (VR) have been suspected in equids, but no extensive epidemiologic study has been performed in a large mixed equine population. Therefore, the aim of this study was to statistically test risk factors for VR in a large population of equids.
Hospital records were reviewed for 3.499 equids, admitted at the internal medicine department of the Liege Equine Teaching Hospital between 1994 and 2011, aged ≥2 years, and which underwent thorough cardiac clinical evaluation. Of this population, 495 cases had ECG and echocardiography performed because of a clinical suspicion of cardiac disease. Chi-square test or logistic regressions (as appropriate) were used to test if breed, gender, age, body weight (BW), and co-existence of various cardiac diseases were risk factors for each VR. Moreover, the risk of development of congestive heart failure (CHF) was tested for each VR. Significance was set at p<0.05.
Most of the studied animals were warmbloods, and observed prevalences were 4.4% for mitral regurgitation (MR), 2.1% for aortic regurgitation (AR), 1.7% for tricuspid regurgitation (TR), and 1.0% for pulmonary regurgitation (PR). Significant risk factors were male gender and increasing age for AR (OR=2.03, CI=1.07-4.94), and racehorses breed group and middle-age for TR (OR=4.36; CI=1.10-17.24). No effect of age or BW was demonstrated for MR. MR was the major valvular disease associated with atrial fibrillation (AF), ventricular tachyarrhythmia, PR and CHF. TR was also linked to AF, PR and CHF; but AR was not linked to CHF.
In conclusion, several previously suspected risks factors for VR were confirmed statistically in this study and should be taken into account in health and athletic monitoring of horses presenting predisposing factors.