Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

C & R II - wk1 > cardiovascular pathology - pt 1 > Flashcards

cardiovascular pathology - pt 1 Flashcards

1
Q

what is the function of the heart

A

pump sufficient volumes of blood to all organs to meet the varying metabolic needs of the animal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the 3 layers of the heart wall

A
  1. endocardium
  2. myocardium
  3. pericardium, visceral layer (epicardium)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is the blood supply to the heart

A
  • left & right coronary arteries & their branches in epicardium -> intramural arteries that penetrate myocardium
  • venules & veins collect blood from heart wall & return it to right atrium via coronary sinus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are the 3 specific characteristics to cardiac myocytes

A
  1. central nuclei
  2. intercalated discs
  3. cross-striations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what are sarcomeres

A

the contractile units composed of actin & myosin filaments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what are intercalated discs

A

specialized junctions between myocytes that allow myocardium to function as a unit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what is the cardiac conduction system composed of

A

modified cardiac myocytes that initate & conduct an electrical impulse -> coordinate cardiac muscle contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is the function of the cardiac valves

A

allow unimpeded unidirectional blood flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are atrioventricular (AV) valves

A
  • supported by tendinous cords (chordae tendinae) & ventricular papillary muscles
  • allow flow from atria into ventricles, prevent backflow into atria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what are semilunar valves

A

allow flow into pulmonary artery & aorta, prevent backflow into ventricles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is heart failure

A

heart is unable to meet the metabolic needs of the animal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

loss of pumping efficiency due to cardiac disease or increased cardiac workload can lead to ____ & _____

A

ischemia and congestion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is ischemia

A

decreased blood flow to the tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is congestion

A

pooling of blood behind the failing chambers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are gross findings of right-sided CHF

A
  • subcutaneous edema
  • ascities
  • chronic hepatic congestion (nutmeg liver)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are gross findings of left-sided CHF

A

pulmonary congestion & edema

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the gross findings of right/left-sided CHF

A
  • pleural effusion
  • common in cats
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are myocardial diseases

A

cardiac responses to increased workload or dysfunction

  • hypertrophy
  • dilation
  • cardiomegaly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is hypertrophy

A

increase in myocardial mass due to increase myocyte size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is dilation

A

increase in chamber volume due to stretching and/or hypertrophy of myocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is cardiomegaly

A

increase in external dimensions of heart due to hypertrophy and/or dilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is concentric hypertrophy

A
  • due to pressure overload
  • sarcomeres added in parallel
  • increase wall thickness
  • decrease chamber volume
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is eccentric hypertrophy

A
  • due to volume overload
  • sarcomeres added in series
  • increase chamber volume (dilation)
  • normal to decreased wall thickness
24
Q

what is cardiomyopathies

A
  • diseases of the myocardium
  • primary (genetic or idiopathic)
  • secondary (known cause other than genetic)
25
Q

what are the 3 main types of cardiomyopathies

A
  • hypertrophic
  • dilated
  • restrictive
26
Q

what is hypertrophic cardiomyopathy (HCM)

A
  • common in cats (esp. young to middle-aged adult males)
  • PRIMARY (heritable) in some cat breeds (known mutation in Maine coon & ragdoll, idiopathic in others)
27
Q

what are the gross findings of hypertrophic cardiomyopathy (HCM)

A
  • englarged heart (cardiomegaly)
  • thick LV wall, decreased LV volume (concentric hypertrophy)
  • +/- LA dilation, thrombosis
28
Q

what is thyrotoxic cardiomegaly

DDX for HCM

A
  • common in cats
  • SECONDARY to hyperthyroidism
  • thyroid gland hyperplasia -> increase thyroid hormone production -> increase production of myocardial contractile proteins -> myocardial hypertrophy
  • potentially reversible on return to euthroidism
29
Q

what are the gross findings of thyrotoxic cardiomegaly

A
  • heart looks similar to HCM
  • enlarged nodular thyroid glands
30
Q

what is dilated cardiomyopathy (DCM)

A
  • most common type in dogs (esp. young to middle-aged giant & large breed)
  • PRIMARY (hertible) in some breeds (doberman, juvenile portuguese water dogs)
  • SECONDARY (acquired) form due to nutritional imbalances (taurine deficiency in dogs & cats)
31
Q

what are the gross findings of DCM

A
  • enlarged rounded heart
  • dilated chambers, thin walls (eccentric hypertrophy), atrophied papillary muscles
32
Q

what is restrictive cardiomyopathy (RCM)

A
  • second most common type of cardiomyopathy in cats
  • endomyocardial fibrosis -> impaired ventricular filling
  • sequela of ENDOMYOCARDITIS (idiopathic inflammation that often follows a stressful event)
33
Q

what are the gross findings of RCM

A
  • thick opaque endocardium (usually involving LV outflow tract)
  • thick LV wall, decreased LV volume (concentric hypertrophy)
  • LA dilation
34
Q

what are cardiomyopathy sequelae (may include)

A
  • arrhythmia (syncope, sudden death)
  • cardiac thrombosis -> thromboembolism
  • aortic (“saddle”) thromboembolism -> hind limb ischemia, paresis
  • thromboemboli to other organs -> ischemia, infarcts
  • congestive heart failure
35
Q

what is myocardial necrosis

A
  • death of cardiac myocytes
  • myocytes have minimal capacity to regenerate
  • irreversible injury -> myocyte necrosis -> inflammation & healing by fibrosis
  • clinical significance determined by location and extent of injury
  • may be subclinical or clinical -> arrhythmias, sudden death, CHF
36
Q

what does acute myocardial necrosis look like grossly

A

myocardial pallor, dry +/- gritty texture (dystrophic mineralization)

37
Q

what does chronic myocardial necrosis look like grossly

A

firm depressed myocardial scar (fibrosis)

38
Q

what are the causes of myocardial necrosis

A
  • nutritional (VE, selenium deficiency)
  • toxic (ionophores)
  • ischemic (coronary vasopasm, thrombosis)
  • genetic (X-linked muscular dystrophy in goldens)
  • traumatic
39
Q

what is nutritional myopathy

A
  • VE/selenium deficiency -> decreased antioxidant activity -> oxidative membrane damage -> cardiac & skeletal myocyte necrosis
  • “white muscle disease” in ruminants & horses
  • “mulberry heart disease” in pigs; accompanies by multiprgan vascular necrosis/thrombosis +/- hepatic necrosis
  • tan foci of myocardial necrosis & mineralization
40
Q

what is myocarditis

A

inflammation of myocardium

41
Q

what are the gross and histological findings of myocarditis

A
  • similar to myocardial necrosis (which may be present)
  • myocytes separated/replaced by inflammatory cells
42
Q

what are the causes of myocarditis

A

often hematogenous infection of local extension from endocardium & pericardium

  • viral
  • bacterial
  • fungal
  • parasitic
43
Q

what are endocardial diseases

A

most clinically significant lesions affect the valves rather than the mural endocardium

44
Q

what is valvular stenosis

A

failure to open completely

45
Q

what is valvular insufficiency

A

failure to close completely

46
Q

what is degenerative valve disease (“endocardiosis”)

A
  • most common cardiovascular lesion in dogs
  • idiopathic degeneration of valvular collagen with replacement by myxomatous matrix
  • most common in smaller breeds, prevalance increases with age. earlier onset with cavalier king charles spaniel
  • mitral > tricuspid&raquo_space; aortic & pulmonic
47
Q

what are the gross findings of degenerative valve disease

A

white, opaque, thickened/nodular valve leaflets with a smooth, glistening surface

48
Q

what is myxomatous valvular degeneration

A
  • valves thickened by loose fibroblastic tissue & wispy blue-gray matrix rich in mucopolysaccharides
  • not an inflammatory lesion
49
Q

what may happen with degenerative valve disease

A
  • valvular insufficiancy: regurgiation (heart murmur)
  • atrial volume overload: eccentric hypertrophy +/- CHF
  • atrial subendocardial fibrosis: “jet lesion”
  • atrial thrombosis: thromboembolism +/- infarcts
  • chordae tendinae rupture
  • atrial tear: hemopericardium
50
Q

what is endocarditis

A
  • inflammation of endocardium
  • bacterial&raquo_space; fungal or parasitic causes
  • tricuspid lesions most common in cattle
  • mitral lesions most common in others
51
Q

what is the pathogenesis of endocarditis

A
  • sustained or recurrent bacteremia & minor endocardial injury at lines of valve apposition
  • bacterial adhesion & proliferation
  • inflammation & further endocardial injury
  • thrombosis
52
Q

what are the gross findings of endocarditis

A

rough, friable, red-tan thrombi (“vegetations”) on valvular endocardium

53
Q

what is vegetative valvular endocarditis

A

septic thombi composed of fibrin, bacteria, neutrophils +/- granulation tissue/fibrosis

54
Q

what may happen with vegetative endocarditis

A
  • death may result from valvular insufficiency (leading to CHF) or effects of bacteremia
  • septic thromboemboli to heart, kidneys, brain, other organs causing: ischemia (infarcts) & infection (inflammation)
55
Q

what is uremic endocarditis

A
  • due to renal failure in dogs
  • endocardial necrosis: mineralization & inflammation of LA endocardium
  • pathogenesis is poorly understood
  • DDX for endocardial mineralization: VD intoxication

C & R II - wk1 (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions