Cardiovascular Pathology 4

Question 0

What changes are seen in arterial hypertrophy?

Answer 0

Local changes are seen in renal arteries and causes chronic nephritis in dogs and cats.
Hypertrophy of the intimal and medial layers in dogs with heart worm.

Question 1

What is arterial hypertrophy?

Answer 1

An increase in the elastic components of the media and intima layers- response to hypertension.

Question 2

What is Arteriosclerosis and what diseases is it seen in?

Answer 2

Fibrous thickening and degeneration of the arterial wall.

Hypertrophic cardiomyopathy in cats and myxomatous mitral valve disease in small dogs.

Question 3

What are sclerotic lesions characterised by?

Answer 3

Mucopolysaccharide accumulation in the intima, followed by fibrosis, calcification and muscle hypertrophy.
Sub-intimal layers are disrupted and there may be duplication of the internal elastic lamina- no marked inflammation, plaques and grey streak-like markings.

Question 4

What is atherosclerosis?

Answer 4

Accumulation of cholesterol in the vessel wall- atheroma.

Rare- can be due to hypercholesterolaemia or hypothyroidism.

Question 5

What is amyloidosis and where are the two types found?

Answer 5

It is an insoluble protein derived from Ig light chain or from SAA.
AL type is associated with Ig-secreting malignant plasma cell neoplasia.
AA type- Ideopathic familial condition

Question 6

Where can amyloid deposits be found?

Answer 6

in renal vessels and glomeruli, splenic white pulp, spaces of Disse (sinusoids), coronary and meningeal arteries.
In the cats=renal medulla, Pancreatic islet cell amyloidosis in older cats.

Question 7

What are the two types of calcification?

Answer 7

Dystrophic-necrosis

metastatic- hypercalcaemia. Large arteries have plaque-like lesions and can be completely encircled.

Question 8

How is Johne’s Disease different in terms of calcification?

Answer 8

Shows metastatic calcification but there is no hypercalcaemia.

Question 9

What is arteritis and what are the two types called?

Answer 9

It is inflammation of the arterial walls.

Infectious and non-infectious

Question 10

What is generalised infectious arteritis?

Answer 10

It is bacterial, e.g. FIP (feline corona virus), distemper.

Question 11

What is localised infectious arteritis and what do the lesions look like?

Answer 11

Local extension of an infective focus, especially if it is suppurative or necrotising. e.g. pasturella spp, meningitis.
Lesions are petechial haemorrhages on serosal surfaces in adrenal glands and visible mucosa.

Question 12

What do localised infectious arteritis lesions look like microscopically?

Answer 12

Lesions affect the endothelium and intima which swell and the muscle layer undergoes necrosis. Thrombosis can occur. lesions tend to be confined to the outer layers.

Question 13

What is polyarteritis nodosa and what do its lesions look like?

Answer 13

It is a non-infectious arteritis. it affects the media of the arteries and arterioles.
fibrinoid necrosis of the media with intense neutrophil invasion.

Question 14

How do the nodules form in polyarteritis nodosa?

Answer 14

As a result of extensive granulation reaction, with eosinophils, plasma cells and lymphocytes.
Could be due to type III hypersensitivity- Ab-Ag complexes.

Question 15

How can parasites cause arteritis?

Answer 15

Strongylus vulgaris- larvae and adults migrate through arterial walls and cause intimal damage. Lesions are found in the ascending aorta, roots of the cr mesenteric, ileocaecal and renal arteries.

Question 16

What are aneurysms?

Answer 16

Balloon-like dilation of the wall of an artery due to weakening and loss of elasticity, blood enters the wall to form a bulge.

Question 17

Were is an aneurysm seen?

Answer 17

Proximal to a stenotic lesion or as a result of weakening following vascular degeneration or excessive blood flow- PDA.
e.g. verminous aneurysm

Question 18

When can aortic rupture occur?

Answer 18

In the horse as a result of a verminous aneurysm- rupture of the root of the aorta. This can happen after a racehorse has run- the heart can cope with the extra strain but the aorta root cannot= sudden death due to haemorrhage into the pericardial sac and cardiac tamponade.

Question 19

What does aortic thrombosis look like grossly?

Answer 19

Firm, dark, red aggregate in the posterior aorta and extending into the iliac arteries.

Question 20

What is aortic thrombosis most common in and what will it result in?

Answer 20

male cats with hypertrophic cardiomyopathy or atrial thrombosis.
Sudden posterior paralysis with hypothermia of hind-limbs and loss of femoral pulse due to embolisation of a left atrial thrombus = “saddle thrombus”

Question 21

What are the two diseases of veins?

Answer 21

Thrombosis, phlebitis or rupture

Question 22

When can venous thrombosis occur?

Answer 22

In cattle with traumatic reticulitis or liver abscesses, the caudal vena cava can become thrombosed.

Question 23

What is phlebitis of veins and how does it occur?

Answer 23

Inflammation of veins. It accompanies thrombosis, vene puncture where sterility is poor or irritants are injected e.g. farmers injecting Ca into milk vv.

Question 24

What is a common type of venous rupture?

Answer 24

Epistaxis in racehorses- Exercise induced pulmonary haemorrhage.