Lecture 6: Cardiomyopathy

Question 1

Cardiomyopathy (Def)

Answer 1

Geterogenous group of disease of mycardium w/ mechanical/electrical dysfunction w/ ventricular hypertropy or dilation

Question 2

Are cardiomyopathies ever genetic?

Answer 2

Yes, typically.

Question 3

To diagnose cardiomyopathy, you must exclude…

Answer 3

Coronary, valvular, and HT diseases

Question 4

Mechanical dysfunction can lead to…(and 4 symptoms)

Answer 4

Progressive heart failure (dyspnea, fatigue, edema, syncope)

Question 5

Electrical dysfunction can lead to…

Answer 5

Arrhythmias and sudden death

Question 6

Two classifications of cardiomyopathy

Answer 6

Primary (confined to heart) or secondary (part of generalized systemic disorder)

Question 7

Morphological and functional classifications of cardiomyopathy (3)

Answer 7

Dilated (progressive dilation and systolic dysfunction); Hypertrophic (decreased compliance –> diastolic dysfunction); Restrictive (stiff mycoardium, decreased compliance –> diastolic dysfunction)

Question 8

What is the most common cardiomyopathy? Which is associated with decreased ejection fraction?

Answer 8

Dilated; dilated again!

Question 9

100% of which morphological cardiomyopathy is related to genetics?

Answer 9

Hypertrophic

Question 10

Dilated cardiomyopathy is generally concomitant with…

Answer 10

Hypertrophy of ventricle

Question 11

What do we see in the heart w/ hypertrophic cardiomyopathy? (3)

Answer 11

Thickened ventricle wall, reduced LV volume, enlarged LA

Question 12

In all 3 morphological cardiomyopathies, what is enlarged?

Answer 12

LA

Question 13

Describe patients with dilated cardiomyopathy (age, onset)

Answer 13

Typically 40-50 years of age, insidious onset

Question 14

The causes of dilated cardiomyopathy are…given examples

Answer 14

Diverse! Idiopathic, familial (~30%), infectious (viral = coxsackie B), inflammatory, toxic (alcohol), metabolic, muscular dystrophy

Question 15

What gene is associated with dilated cardiomyopathy?

Answer 15

TTN, encodes for titin, the largest protein expressed in humans

Question 16

Describe common features of dilated heart

Answer 16

Large, globular, flabby heart; dilation of AV valves, fibrous thickening, mural thrombosis (stasis)

Question 17

Histologic features of dilate cardiomyopathy are…Name a few findings

Answer 17

Non-specific; myocytes w/ box-car nuclei, some myocytes are attenuated/irregular; interstitial and endocardial fibrosis

Question 18

What are some disease-related causes of dilated cardiomyopathy? What do we find with viral cardiomyopathy?

Answer 18

Viral: Coxsackie, adenovirus (white spots, congested vessels, lymphocyte aggregates); Parasitic: Chagas (amastigoes within cytoplasm)

Question 19

Three causes of noninfective cardiomyopathy

Answer 19

Granulomatous inflammatory disease; Hypersensitivity myocarditis; Collagen vascular disease

Question 20

What is diagnostic of granulomatous inflammatory diseae?

Answer 20

Multinucleated giant cells

Question 21

What do we see with sarcoidosis?

Answer 21

White patchy discoloration and non caseating granulomas

Question 22

What do we see with hypersensitivity myocarditis?

Answer 22

Eosinophil-rich infiltrate

Question 23

What drugs/toxins can lead to dilated cardiomyopathy?

Answer 23

Alcohol, cocaine, chemotherapeutic agents

Question 24

T/F: Alcohol is a major cause of dilated cardiomyopathy

Answer 24

True

Question 25

What is a cause of dilated cardiomyopathy that only women get?

Answer 25

Peripartum

Question 26

What is a metabolic cause of dilated cardiomyopathy?

Answer 26

Hemochromatosis (iron storage disorder)

Question 27

Hypertrophic cardiomyopathy is an important cause of sudden cardiac death in…

Answer 27

Young males

Question 28

What is the most common gene related to hypertrophic cardiomyopathy? What kind of heredity?

Answer 28

Genes encoding beta-myosin heavy chain; AD w/ complete penetrance

Question 29

The hypertrophy is…

Answer 29

Asymmetric: proportionately greater hypertrophy of the interventricular septum (IVS) than the free LV wall

Question 30

What causes fatal arrhythmias in hypertrophic cardiomyopathy?

Answer 30

Aberrant myofibers in conduction system

Question 31

How can you tell HT and HCM apart grossly?

Answer 31

HT = concentric, symmetric; HCM = asymetric septal hypertrophy

Question 32

What is a characteristic gross feature of hypertrophic cardiomyopathy in the mitral valve?

Answer 32

White-ish mitral valve impact lesion

Question 33

Histologically, what do we see in hypertrophic cardiomyopathy? Why is this important?

Answer 33

Myocardial fiber disarray; regular conduction is not possible –> arrhythmia

Question 34

Restrictive cardiomyopathy is the ________ common

Answer 34

Least

Question 35

Primary and secondary etiology of restrictive…

Answer 35

Primary: tropical endomyocardial fibrosis; Secondary: amyloidosis (most common), sarcoidosis, storage/metabolic disorders (hemochromatosis)

Question 36

Describe Loefflers endomyocarditis

Answer 36

Males, temperate climates, death w/in months, hypereosinophilic states

Question 37

What do we see in amyloidosis? What stains? What is most common?

Answer 37

Gross: englarged atrium w/ waxy appearance; histologically: pale pink inflitrate; CongoRed (apple green) and immunoflourescent tests; AL

Question 38

What is Arhythmogenic Right Ventricular Cardiomyopathy (ARVC)? What happens grossly?

Answer 38

Rare, inherited disease with mutations in desmosomal proteins that primarily affects RIGHT ventricle; fatty tissue replaces heart muscle

Question 39

What is Left Ventricular Noncompaction (LVNC)? What happens grossly?

Answer 39

Arrest in endomycoardial morphogenesis in embryonic development; sponge-like appearance of left ventricular wall