Lecture 21 9/27/24 Flashcards
What is hemangiosarcoma?
malignant tumor of endothelial cells
What are the characteristics of hemangiosarcoma?
-very common in dogs
-right atrium most common site
-rupture or oozing results in hemopericardium and cardiac tamponade
-grossly hemorrhagic, cavitated, and irregularly shaped
What is chemodectoma?
heart base tumor/aortic body tumor
What are the characteristics of chemodectoma?
-most common in dogs but also seen in cats and cattle
-arise from aortic body between aorta and pulmonary artery
-chemoreceptor organs are responsive to alterations in blood O2 levels
-grossly spherical, smooth, and firm
What are the characteristics of lymphoma?
-cardiac location is most common in cattle but occurs in dogs and cats
-often caused by Bovine Leukosis Virus infection
What are the types of arteriovenous communication closure failures?
-patent ductus arteriosus
-atrial septal defect
-ventricular septal defect
-AV canal defect
What are the characteristics of PDA?
-normally patent in fetus and in foals up to 5 days old
-location is centimeters above aortic valve
What must atrial septal defect be distinguished from?
patent foramen ovale, which has a flap
What is AV canal defect?
open communication between all 4 chambers of the heart, which is most common in calves
What are the characteristics of pulmonic stenosis?
-common in dogs
-may be subvalvular, valvular, or supravalvular
-causes marked right ventricular hypertrophy
-commonly mistaken for HCM
Which breeds are predisposed to subaortic stenosis?
-golden retriever
-newfoundland
What are the characteristics of subaortic stenosis?
-fibrous tissue below aortic valve
-any fibrous tissue on interventricular septum below aortic valve is abnormal
-results in marked left ventricular hypertrophy
-myocardial necrosis and sudden death are common
What are the characteristics of mitral valve dysplasia?
-can be subtle, so short and thick chordae tendinae are looked for
-thickened, nodular, and fused valve leaflets
-results in valvular insufficiency and dilated left atrium
What are the characteristics of tricuspid valve dysplasia?
-thickened, nodular, and fused valve leaflets
-short or absent chordae tendinae
-results in valvular insufficiency and dilated right atrium
What are the components of Tetralogy of Fallot?
-ventricular septal defect
-overriding aorta
-pulmonic stenosis
-right ventricular hypertrophy
What are the characteristics of persistent right aortic arch?
-common in German Shepherds
-ductus arteriosus compresses esophagus on left side
-esophagus is only dilated cranial to heart base
What are the characteristics of anomalous coronary arteries?
-common in calves
-can result in ischemic myocardial necrosis
-sudden death or myocardial dysfunction and CHF occur
What are the characteristics of arteriosclerosis?
-thickening/hardening of arteries
-fibrosis and mineralization
-common aging change in caudal abdominal aorta in dogs; predisposes to aortic thrombosis
What are the characteristics of atherosclerosis?
-intramural deposition of lipids
-rarely seen in dogs
-seen in dogs with diabetes mellitus or hypothyroidism
What are the characteristics of aortic rupture?
-though to be due to trauma, excessive internal pressure, or both
-uncommon in animals but most often seen in horses
-aorta is normal in most horses; may have defect in Friesians
What is hemangioma?
benign tumor of endothelial cells of blood vessels
What are the characteristics of hemangioma?
-dermal hemangioma in dogs can be associated with sun exposure
-dermal hemangioma can undergo malignant transformation
-subcutaneous hemangioma is a common benign tumor
Which breeds are predisposed to hemangiosarcoma?
-golden retriever
-german shepherd
What are the common primary sites for hemangiosarcoma?
-spleen
-right atrium
-liver
What are the metastatic sites for hemangiosarcoma?
-lung
-liver
-kidney
-brain
-spleen
-right atrium
What is lymphangiosarcoma?
malignant tumor of endothelial cells of lymphatic vessels
What are the characteristics of lymphangiosarcoma?
-found in caudal ventral abdominal subcutis in cats
-very rare in other species
-NOT lymphoma
