Aortic Rupture
Aortic rupture is caused by severe trauma such as a traffic accident, a congenital defect or weakness, or by an _______________ created by the migration of strongyles larvae within the aorta. Any of these situations causes an area of weakness in the wall of the aorta. As blood pressure increases during exercise the ____________________ pressure within the aorta exceeds the structural integrity of the aorta at the site of weakness causing massive haemorrhage into the thorax or abdomen. Haemorrhagic shock occurs usually followed by death within _____________ minutes of the rupture. Horses with internal parasite infestations or those with a poor history of de-worming are at a higher risk of suffering from aortic rupture. Aortic rupture is seen clinically as pale mucous membranes, weakness, trembling, syncope, collapse and sudden death following trauma or heavy exercise. Diagnosis of aortic rupture is usually made ___________________ ; however partial ruptures may be able to be diagnosed through radiography or ultrasound. Treatment is the surgical repair of the aorta; however __________________ percent of affected individuals die within minutes of rupture and eighty to eighty-five percent of those who survive the initial rupture die before surgery can take place.
Prognosis is grave.
Valvular Heart Disease
Valvular heart disease describes a group of conditions affecting the integrity or function of one or more valves in the heart. The valve most commonly affected is the aortic valve, followed by the mitral valve, the tricuspid valve and the pulmonary valve. Valvular disease is characterized by ___________________________ , which are audible with a stethoscope. Poor performance and heart failure also commonly accompany valvular disease. Valve disease is not common in horses though parasitic damage to the heart valves is not unknown.
Aortic Valve Insufficiency
Aortic valve insufficiency describes the dysfunction of the aortic semilunar valve. This valve is located between the _______________ and the ________________ . This valve functions to prevent the backflow of blood from the aorta into the left ventricle.
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