Cardiomyopathy Pathology DS

Question 1

Cardiomyopathy?

Answer 1

describe heart disease resulting from an abnormality in the myocardium

Question 2

Primary cardiomyopathies?

Answer 2

disease primarily confined to the heart muscle

Question 3

Secondary cardiomyopathies?

Answer 3

have myocardial invlolvement as a component of a systemic or multiorgan disorder

Question 4

Categories of Cardiomyopathies?

Answer 4

Dilated cardiomyopathy, Hypertrophic cardiomyopathy, restrictive cardiomyopathy, other causes, left ventricular noncompaction

Question 5

Common cause of Dilated Cardiomyopathy (DCM)?

Answer 5

Genetic autosomal dominance, gene that encodes dystrophin

Question 6

Dystrophin?

Answer 6

cell membrane associated cytoskeletal protein that plays a critical role in couping the internal cytoskeleton to the extracellular matrix

mutated in most skeletal myopathies

Question 7

Other causes DCM?

Answer 7

myocardities, alcohol (beriberi), childbirth

Question 8

Gross morphology DCM?

Answer 8

enlarged heart, heavy
mural thrombi
mitral reguritation (left or right ventricle dilation)

Question 9

Mitral reguritation?

Answer 9

when the Left ventricle contracts blood flows back into the left atrium because the mitral valve did not close properly

Question 10

Micro morphology DCM?

Answer 10

nonspecific and usually do not point to any particular etiologic agent
can be hypertrophied, irregular cells, variable fibrosis present

Question 11

Clinopathologic pattern of DCM?

Answer 11

Same no matter the cause
end stage- ejection fraction less than 25%, 50% die within 2 years

secondary mitral regurgitation and abnormal cardiac and abnormal cardiac rhythms are common

death from progressive cardiac failure or arrthymia, embolism from thrombus can occur

Question 12

DCM is primarily?

Answer 12

impairment of contractility

Question 13

treat DCM?

Answer 13

cardiac transplant, long term ventricular assist

Question 14

Arrhythmogenic right ventricular cardiomypathy (ARVC)?

Answer 14

under the category of DCM
inherited disease of cardiac muscle that causes right ventricular failure and various rhythm disturbances (ventricular tachycardia or fibrilation)
– sudden death in young people

Question 15

ARVC cause?

Answer 15

defective cell adhesion protein in desmosome that link adjacent cardiac myocytes

Question 16

Naxos syndrome?

Answer 16

disorder characterized by ARVC and hyperkeratosis of plantar palmar skin surfaces that is associated with mutation in gene encoding plakoglobin

Question 17

Hypertrophic cardiomyopathy? (HCM)

Answer 17

myocardial hypertrophy, poorly compliant left ventricle mycardium leading to abnomal diastolic filling, and sometimes intermittent ventricular outflow obstruction

Question 18

HCM summary?

Answer 18

impairment of compliance (diastolic dysfuntion)

thick walled, heavy, hypercontracting

Question 19

Common cause HCM?

Answer 19

single gene mutation
most common cardiovascular problem caused by single gene mutation

genes encoding proteins on the sarcomere

Question 20

Most common gene/protein in HCM?

Answer 20

gene encoding Beta myosin heavy chain (most)

cardiac TnT, alpha tropomyosin, myosin binding protein C

Question 21

Common btw DCM and HCM?

Answer 21

hypertrophy, dilation, fibrosis, intersitial

lead to heart failure, sudden death, atrial fibrilation, stroke

Question 22

DIfference DCM and HCM?

Answer 22

HCM has a thick walled, heavy, hypercontracting heart
HCM is caused by mutations in the sarcomere while DCM is a disease caused my abnormalities of cytoskeletal proteins
DCM is flabby, hypercontracting

Question 23

Gross morph of HCM?

Answer 23

massive myocardial hypertrophy, asymmetrical is more common
thickened ventricular septum
endocardial thickening, mural plaque formation in left ventricular outflow tract and thickening of anterior mitral leaflet– echo functional left ventricular outflow tract obstruction during midsystole

Question 24

histo findings HCM?

Answer 24

extensive myocyte hypertrophy
haphazard disarray of bundles of myocytes, individual myocytes, and contractile elements in sarcomeres within cells
intersitial and replacement fibrosis

Question 25

Clin features of HCM?

Answer 25

reduced stroke volume from decreased diasolic filliing, harsh systolic ejection murmur
focal myocardial ischemia, angina

Question 26

Treat HCM?

Answer 26

beta andrenergic blockers, reduce mass of septum

Question 27

Restrictive cardiomyopathy?

Answer 27

primary decrease in ventricular compliance, resulting in impaired ventricular filling during diastole

Impairment of compliance (diastolic dysfunction)

Question 28

Common cause of restrictive cardiomyopathy?

Answer 28

idiopathic
Associated with distinct disease or process that affect the myocardium, principally radiation fibrosis, amyloidosis, sarcoidosis, metastatic tumors, or the deposition of metabolites that accumulate due to inborn errors of metabolism

Question 29

Gross morphology of Restrictive cardiomyopathy?

Answer 29

ventricles normal/enlarged, cavities are not dilated, myocardium firm and noncompliant
biatrial dilation is common

Question 30

Histo morphology of Restrictive cardiomyopathy?

Answer 30

patchy or diffuse intersitial fibrosis, minimal to extensive

endomyocardial biopsy will reveal a specific etiology

Question 31

Other restrictive conditions?

Answer 31

Endomyocardial fibrosis
Loeffler endomycoarditis
Endocardial fibroelastosis

Question 32

Myocarditis?

Answer 32

group of pathologies, infectious microoragnsisms and/or inflammatory process cause myocardial injury

Question 33

Common cause myocarditis?

Answer 33

Cosackieviruses A and B in the US (viral infections most common) HIV

Nonviral- Trypansoma cruzi (Chagas disease), Lyme disease (Borrelia burgdorferi)

Noninfectious- hypersensitivity reaction to drugs (antibiotics, diuretics, antihypertensive drugs)

Question 34

Gross morphology of Myocarditis?

Answer 34

heart may be normal/dilated, venticular myocardium flabby and often mottled in advanced
mural thrombi may be present

Intersitial inflammatory infiltrate associated with focal myocyte necrosis

Question 35

Hypersensitivty myocariditis?

Answer 35

intersitial infiltrates, principally perivascular
(lymphocytes, macrophages, high proportion eosinophils)
Giant cell myocarditis

Question 36

Clin features of myocarditis?

Answer 36

asymptomatic to precipitous onset of heart failure r arrhythmias

btw- fatigue, dyspnea, palpitations, precordial discomfort, fever

Question 37

Other causes of myocardial disease?

Answer 37

Cardiotoxic drugs
Catecholamines
Amyloidosis
Iron overload
Hyperthyroidism/Hypothyroidism

Question 38

Takotsubo cardiomyopathy?

Answer 38

sudden intense emotion or physical stress can induce acute left ventricular dysfunction due to myocardial stunning

Question 39

Cardiac amyloidosis produces what kind of cardiomyopathy?

Answer 39

Restrictive, varied based on location of deposit

deposits often form rings around cardiac myocytes and capillaries