Preliminary Report on Myrna Loy's Necropsy (Animal Autopsy)

Gross Description

MYRNALOY Feline
6 years

Necropsy Preliminary Report

A 6 year old spayed DSH died on 8/19/15. The cat had a history of clotting secondary to heart disease. Owner isconcerned about gastric and renal disease. A 4.45 kg female spayed cat is necropsied on 8/19/15. Autolysis is mild. There are adequate visceral fat stores and the body condition score is 6/9. The eyes are mildly sunken into the orbits, and mucous membranes are pale pink. The thoracic cavity and pericardial sac respectively contain 15-20 ml of red, clear, slightly opaque fluid, and 5 ml of dark red clear fluid. The parietal surfaces of the pericardial sac and pleura are multifocally and loosely adhered to the thoracic wall by numerous fibrinous adhesions. The edges of the cranioventral lung lobes are collapsed and plumb colored. All lung lobes float in formalin. The heart is enlarged weighing 20.1 g (0.45% of total body weight), and the right ventricular free wall and left ventricular free wall respectively measure 0.1 cm (RVF) and 0.8 cm (LVF). The left atrioventricular valvular leaflets contain numerous, 0.2-0.3 mm in diameter, tan, firm, smooth nodules. Lining the endocardial surface of the left ventricle are ~10, thin, white-pink, string-like bands of connective tissue (moderator bands) bridging the ventricular septum and the left ventricular free wall. The liver has slightly round edges and a prominent reticulated pattern. The cortex of both kidneys is slightly granular. There are no additional remarkable gross lesions.

Heart:

Left ventricular concentric hypertrophy

Left atrioventricular endocardiosis

Excessive moderator bands

Liver: Mild hepatomegaly and centrilobular congestion

Pericardial sac: Pericardial effusion

Lung: locally extensive atelectasis and mild fibrinous pleuritis

Comments

The heart was overall large and the left ventricle was markedly thickened, consistent with hypertrophic cardiomyopathy which is a condition in which the muscle of the heart thickens (especially on the left side) and compromises the contractility and blood-pumping efficiency of the heart. Left sided heart failure often presents clinically with a thoracic/pleural effusion, as seen in this case; however, the slight milky consistency suggest a chylous/lymph component which can occur if there is damage to the thoracic duct. In addition, the large liver and centrilobular congestion are common changes seen in right sided heart failure. There was also evidence of endocardiosis of the mitral valve, and excessive moderator bands, but the significance of these changes in relation to the enlarged heart is unknown.  Endocardiosis is a common age related degenerative of the valvular leaflets. If severe, these lesions can cause leaky valves and eventually heart failure, but the changes were mild in this case. Excessive moderator bands have been observed in normal cats and in cats with hypertrophic cardiomyopathy, but the significance is unknown.

A final report is pending histopathologic examination of all the major organ systems.