Anatomical and ultrasonographic approach to the heart of the shetland pony (Equus ferus caballus): does size matter?

Abstract

The Shetland pony is a unique equine breed due to its anatomical and morphological characteristics. In addition, its usefulness as a pet determines the importance of its specific characteristics. The purpose of this study was to describe the anatomic features of the normal heart of a group of Shetland ponies using transthoracic echocardiography, gross dissections, and anatomical sections. Transthoracic echocardiography was performed in 12 Shetland ponies obtaining longitudinal and transverse images. After transthoracic echocardiography imaging, 4 Shetland ponies’ hearts were dissected and sectioned to facilitate the interpretation of previous transthoracic echocardiography images. Anatomic details of the heart of the Shetland pony were identified and compared according to other 4 dissections and sections of standard horse's heart. Macroscopic and echocardiographic measurements were additionally performed. The information obtained provided a valid anatomic pattern of the heart of the Shetland pony, and useful information for anatomical transthoracic echocardiography and clinical studies of this structure.