PREVALENCE OF VALVULAR REGURGITATIONS IN CLINICALLY HEALTHY CAPTIVE LEOPARDS AND CHEETAHS: A PROSPECTIVE STUDY FROM THE WILDLIFE CARDIOLOGY (WLC) GROUP (2008-2013)

Abstract

The purpose of this prospective study was to evaluate transthoracic echocardiograms from clinically healthy large felids for the presence of valvular regurgitations (VR). Physiologic VR commonly occur in normal dogs and cats, but the percentage of large felids with VR has not been previously reported. During a 5-yr study period (2008-2013), 28 healthy animals were evaluated under general anesthesia: 16 cheetahs (Acinonyx jubatus soemmeringuii) with a mean age of 1.5±0.8 yr (range 0.7-3.5 yr), 5 Amur leopards (Panthera pardus orientalis), 1 snow leopard (Uncia uncia), and 6 clouded leopards (Neofelis nebulosa). For this study, all the leopards were gathered in one so-called "leopards group" with a mean age of 2.8±3.4 yr (range 0.3-10.7 yr). All valves observed in each view were examined for evidence of regurgitant jets and turbulent blood flow using the color-flow Doppler mode. Valves were also examined for structural changes. Mitral valve and aortic cusp abnormalities were considered to be of congenital origin. Mitral valve lesions led to mitral insufficiency in all the felids. Aortic cusp abnormalities led to aortic regurgitation in 94% of the cheetahs and 67% of the leopards. Leopards showed a predominance of early systolic mitral regurgitations, whereas all the mitral regurgitation jets in cheetahs were holosystolic. Tricuspid regurgitation was found in 81% of the cheetahs and in 50% of the leopards, whereas pulmonic regurgitation was detected in 44% of the cheetahs and 33% of the leopards. Interestingly, none of these tricuspid and pulmonic regurgitations were associated with two-dimensional structural valve abnormalities, thus suggesting their physiologic origin, as described in humans, cats, and dogs. In conclusion, subclinical valvular diseases are common in apparently healthy leopards and cheetahs. Longitudinal follow-up of affected animals is therefore required to assess their clinical outcome.

Keywords: Acinonyx jubatus; Neofelis nebulosi; Panthera pardus orientalis; Uncia uncia; congenital heart anomaly; valvular insufficiency..