FELINE ENDOMYOCARDITIS AND LEFT-VENTRICULAR ENDOCARDIAL FIBROSIS

A retrospective study was conducted of all feline necropsies over a 7- year period. Of a total of 1,472 necropsies, 37 cases of endomyocardit is (EMC) and 25 cases of left ventricular endocardial fibrosis (LVEF) (previously called restrictive or intermediate cardiomyopathy) were id entified. There was a subset of four cats with EMC that had histologic features of both diseases. Interstitial pneumonia was seen in 25 of 3 5 cats (71%) with EMC but in only seven of 25 cats (28%) with LVEF. Th rombi or thromboemboli were seen in 14 of 25 cats (56%) with LVEF but in only six of 37 of cats (16%) with EMC. In both LVEF and EMC, thromb oemboli were located in the abdominal aorta, left atrium and ventricle of the heart, femoral artery, cranial mesenteric artery, liver, pulmo nary artery, jugular vein, or a meningeal vessel. Each cat had a singl e thrombus/thromboembolus, except for four cats with LVEF that had mor e than one. The histologic and clinical findings suggest that EMC and LVEF represent temporally different manifestations of a single disease entity.