Craft

Question 1

Can mature cardiac muscle cells divide?

Answer 1

No - respond to stress by atrophy, hypertrophy, degeneration, necrosis, fibrosis

Question 2

Hypertrophy

Answer 2

Requires healthy myocardium

Myocytes get thicker until nutrition used up, then responds by dilating (stretching of myofibers)

Question 3

Cardiac compensatory methods

Answer 3

Hypertrophy
Increased HR
Increase peripheral resistance
Increase in blood volume
Redistribution of blood flow (movement to areas of lowest pressure, peripheral vasoconstriction, shunting)

Question 4

Clinical signs of cardiac decompensation

Answer 4

Cardiac syncope (acute)
Congestive heart failure (chronic)

Question 5

Cycle of cardiac decompensation

Answer 5

The failing heart must pump a greater volume of thicker fluid

Decompensation -> hypoxia -> RAAS -> edema -> EPO -> increased blood viscosity

Question 6

What can cause cardiac hypertrophy?

Answer 6

Chronic pressure overload
Chronic volume overload
Hyperplasia

Question 7

Concentric cardiac hypertrophy

Answer 7

an increase in the mass of the ventricle without increase in end-diastolic volume (preload)
Increased systolic volumes (afterload)

Aortic stenosis, pulmonic stenosis, pulmonary hypertension in PDA, cats with hyperthyroidism

Decrease in ventricular lumen

Walls are very fat

Question 8

Eccentric cardiac hypertrophy

Answer 8

An increase in myocardial mass with increased end-diastolic volume (preload)
Dilated chamber

AV or semilunar valve insufficiencies
Arteriovenosus shunts

Walls are not fat, just bigger

Question 9

With cardiac hypertrophy, what can cause the endocardium to look opaque?

Answer 9

subendocardial fibrosis

Question 10

Causes of left sided heart failure

Answer 10

Myocardial loss of contractility
Valvular insufficiency (mitral, aortic)
Congenital defects

Question 11

Causes of right sided heart failure

Answer 11

valvular insufficiency (tricuspid, pulmonary)
pulmonary hypertension
cardiomyopathy

Question 12

Cor pulmonale

Answer 12

right heart failure secondary to pulmonary disease

pulmonary dz, dirofilariasis, pulmonary thromboembolism, neoplasia

Question 13

What is a sign of cor pulmonale caused by dirofilariasis?

Answer 13

Endarteritis

Question 14

Congenital heart defects of dogs

Answer 14

PDA
pulmonic stenosis
subaortic stenosis

Question 15

Congenital heart defects of cattle

Answer 15

atrial and ventricular septal defects

transpositions of main vessels

Question 16

Congenital heart defects of pigs

Answer 16

Subaortic stenosis

endocardial cushion defects

Question 17

Congenital heart defects of cats

Answer 17

endocardial cushion defects

left AV valve insufficiency

Question 18

Malformations causing left to right shunting

Answer 18

Atrial septal defect
Atrioventricular septal defect
Ventricular septal defect
PDA

Question 19

Causes of atrial septal defect

Answer 19

Sinus venous defect
ostium primum defect
ostium secondum defect

Question 20

What does an atrial septal defect ultimately result in?

Answer 20

Cyanosis

Question 21

Atrioventricular septal defects are also know as what

Answer 21

Endocardial cushion defects

AV canal defects

Question 22

Causes of AV septal defects

Answer 22

ostium primum defect

VSD with a cleft in the right AV valve

Question 23

What three parts of the embryonic heart form the interventricular septa?

Answer 23

Muscular portion
Downward growth of the conotruncal ridges
Membranous portion of the septum derived from the endocardial cushions

Question 24

What do most VSDs involve?

Answer 24

The membranous septum

Question 25

Eisenmenger complex

Answer 25

VSD cases with reversal and right to left shunting

Question 26

What are consquences of VSDs?

Answer 26

Eccentric ventricular hypertrophy | Cyanosis, death

Question 27

What do valvular insufficiencies increase?

Answer 27

preload

Question 28

What does valvular (semilunar) stenosis increase?

Answer 28

Afterload

Question 29

What does AV valve stenosis increase?

Answer 29

preload

Question 30

What do you see subendocardial hemorrhage with?

Answer 30

``` septiciemia endotoxemia anoxia electrocution trauma agonal change ```

Question 31

Subendocardial mineralization

Answer 31

``` dystrophic or metastatic vit D toxicity calcinogenic plant toxicosis calcium phosphorus imbalance johnes disease ```

Question 32

Vegetative valvular and mural endocarditis

Answer 32

usually bacterial, septic emboli lodge in heart usually mitral valve Grey masses of fibrin ("vegetations")

Question 33

Causes of endocarditis

Answer 33

sepsis | uremia

Question 34

Uremic endocarditis

Answer 34

dogs acute or repeated uremia ulcerative left atrium

Question 35

Diseases that distort valves

Answer 35

endocardiosis valvular stenosis valvular dysplasia hematocysts and lymphocysts

Question 36

Endocardiosis

Answer 36

Myxomatous valvular degeneration small, toy breeds Mitral>tricuspid Short, thick valves with smooth tan nodules

Question 37

Sequelae of endocardiosis

Answer 37

``` valvular incompetency congestive heart failure atrial dilation jet lesions left atrial rupture (hemopericardium) chordae tendinae rupture ```

Question 38

Hematocysts or lymphocysts

Answer 38

Ruminants do not cause problems regress within a few months of birth

Question 39

Myocardial diseases

Answer 39

myocardial necrosis myocarditis cardiomyopathies

Question 40

Causes of myocardial necrosis

Answer 40

infectious nutritional (vit E and selenium, thiamine, copper) exertional toxic (monensin, cardiac glycosides, doxorubicin)

Question 41

Brain-heart syndrome

Answer 41

subendocardial necrosis seen following acute brain or CNS injury Caused by coronary artery spasm and excess catecholamine release

Question 42

Myocarditis

Answer 42

Inflammation of myocardium hematogenous Causes conduction abnormalities Chronically can lead to congestive heart failure

Question 43

Causes of myocarditis

Answer 43

``` Viruses (parvo) Bacteria (clostridium - black leg) Fungal (blastomyces) Protozoa (trypanosoma cruzi) Helminths ```

Question 44

three forms of cardiomyopathies

Answer 44

dilated hypertrophic restrictive

Question 45

restrictive cardiomyopathy

Answer 45

impaired filling, fibrosis cats also called left ventricular endocardial fibrosis

Question 46

What is feline dilated cardiomyopathy associated with?

Answer 46

taurine deficiency

Question 47

feline excessive moderator bands

Answer 47

Excess bands in left ventricle bridging the septum to the free wall heart failure and death

Question 48

hydropericardium

Answer 48

excess of clear fluid in pericardial sac | usually accumulates slowly to stretch the pericardium so dont see tamponade

Question 49

hemopericardium

Answer 49

blood in pericardial sac will clot usually a result of cardiac rupture

Question 50

Serous atrophy of pericardial fat

Answer 50

cachexia of any cause

Question 51

fibrinous pericarditis

Answer 51

usually due to hematogenous microbial infections | glassers disease in pigs

Question 52

purulent pericarditis

Answer 52

Pyogenic bacteria | Usually in cattle from foreign body in reticulum penetrating

Question 53

Neoplasms of the heart

Answer 53

Chemodectomas (aortic body tumors) Ectopic thyroid and parathyroid tumors Rhabdomyomas Metastatic lymphoma