Overview The equine heart is a hollow organ com- prised of two chambers—one with two atria and the other with two ventricles—that function in concert to receive deoxygenated blood from veins into the right side and sub- sequently propel oxygenated blood through the body via arteries from the left side. Cardiac disease is considered the third- most-common cause of “poor performance” in athletic horses (after musculoskeletal disease and respiratory disorders); how- ever, cardiac abnormalities are rare. Horses with cardiac dysfunctiontypically present with a history of poor performance/exercise intolerance, distended veins, swelling of the limbs, weakness, or collapse. Structure and Function The equine heart is located in the ante- rior region, largely covered (externally) by the forelimbs. The exact anatomic loca- tion within the chest cavity and the overall size of the heart is breed-dependent. The equine heart is a four-chambered, hollow, muscular organ divided into right and left sides by a septum (wall). Each side has an atrium (a receiving chamber) and a ven- tricle (an ejecting chamber). Blood is dumped into the right ventricle from the venous circulation via the infe- rior and superior vena cava. This oxygen- poor blood then flows through the right atrioventricular valve (also known as the tricuspid valve) to the right ventricle. The right ventricle contracts to pump the blood through the pulmonic valve and pulmo- nary arteries to the lungs, where oxygen is loaded onto the hemoglobin within the red blood cells. Oxygenated blood returns to the heart by way of pulmonary veins to the left atrium and ventricle, which are separated by the left atrioventricular (mi- tral) valve. Finally, the oxygenated blood in the muscular left ventricle is pumped out of...
Website: www.thehorse.com | Filesize: 354kb
No of Page(s): 2
Download Cardiology: The Equine Heart.pdf
No comments:
Post a Comment