Lecture 43: Endocardial, Valvular, & Epicardial/Pericardial Diseases

What is the function of the heart valves?

separate different chambers of the heart to that during contraction there’s time for ventricular filling

What species do hematocysts and lymphocysts occur most commonly in?

ruminants

What is affecting these heart valves?

hematocyst (top) and lymphocyst (bottom)

What is endocardial mineralization?

variable size coalescing, gritty white plaques associated with the endocardium of valve leaflets

What are the causes of endocardial mineralization?

• Vitamin D - rodenticides, plants

• granulomatous disease: johne’s disease, fungal disease

• uremia

What has occurred in this heart? note the gritty white plaques near the valve leaflets.

endocardial mineralization

What condition is this an example of? note the white plaques in this aorta.

endocardial mineralization (calcification due to vitamin D toxicosis

What is ulcerative endocarditis caused by and where is it typically seen?

caused by uremia typically seen in the left atrium > right atrium in dogs

What is affecting this canine heart? note the white-yellow plaques.

ulcerative endocarditis

What is vegetative valvular endocarditis the result of?

chronic bacterial infections (in horses usually a result of jugular vein thromboses from catheterization)

What valves does vegetative valvular endocarditis have a predilection for?

mitral > aortic > tricuspid > pulmonary

How does vegetative valvular endocarditis present?

large adhered, tan to mottled red, irregular, and rough friable vegetations (nodules) associated with the heart valves → pieces will break off forming emboli and shower other tissues

What is affecting this heart? note the rough irregular nodules around the heart valves.

vegetative valvular endocarditis

What cardiac disease has a predilection for male middle aged-older dogs, specifically cavalier king charles spaniels and effects mostly the mitral valve?

valvular endocardiosis (myxomatous valvular degeneration)

How does valvular endocardiosis present?

smooth raised off white to coalescing nodular thickenings associated with the AV valve leaflets often associated with contraction of the valve leaflet

What is affecting this cavalier king charles spaniel’s heart? note the off white nodular thickenings around the AV valve leaflets.

valvular endocardiosis (myxomatous valvular degeneration)

What is fibrinous to fibrinosuppurative pericarditis typically a result of?

bacterial septicemia

What is affecting this equine heart? note the heart is covered dorsally by a thick, yellow layer of fibrin.

fibrinous pericarditis

What is affecting this heart?

clostridium chauveoi (black leg)

What has affected this bovine heart? The owner had recently purchased this bovid and usually gives his herd magnets, but this bovid died before he could administer one.

traumatic reticulopericarditis aka hardware disease

What species is visceral gout common in?

avian and reptilian species

What is visceral gout?

deposits of uric acid caused by dehydration or renal disease

What is affecting this chicken heart? The owner noted that their automatic water filler broke recently.

visceral gout due to dehydration

What are the causes of epicardial mineralization?

•Vit E/ Selenium deficiency (extension of myocardial mineralization)

•Vit D toxicosis

•Hereditary (mice and hamsters)

•Spontaneous (rats and guinea pigs)

What has occurred in this heart? The animal was emaciated.

serous atrophy of pericardial fat (gelatinous transformation of fat)