RESUMO
INTRODUCTION: Aortic dissection is characterized by a tear in the aortic wall resulting in blood from the aortic lumen penetrating into the media, which causes dissection. When aortic dissection does not cause rupture, it provokes localized dilation of the aorta or aneurism, also called dissecting aortic aneurism (DAA). This case report describes a DAA in a cat associated with systemic arterial hypertension (SAHT). A 10-year-old male Domestic shorthair cat was presented for cardiac evaluation. Anamnestic clinical complaints were a syncope associated with paraparesis and weak femoral pules. Cardiomegaly had been found radiographically, and cardiogenic arterial thromboembolism had been suspected. Upon presentation physical abnormalities were tachycardia and a heart murmur. Measurement of systolic systemic arterial blood pressure (SABP) revealed severe SAHT. Echocardiographic images showed severe DAA, and marked aortic valve insufficiency. Palliative antihypertensive treatment resulted in fast clinical improvement and significant decrease in blood pressure. Four months later, acute severe respiratory distress due to cardiogenic pulmonary edema led to the cat's euthanasia. In human medicine, DAA is a well-reported complication of SAHT. This is the second case of DAA with congestive heart failure reported in a hypertensive cat.