The Heart 3

Question 0

All cardiomyopathies are characterized by______dysfunction.

Answer 0

Ventricular

Question 1

Cardiomyopathies are ________ diseases of the myocardium characterized as ________ cardiac dysfunction, as opposed to dysfunction secondary to ischemia, valvular, or hypertensive diseases.

Answer 1

intrinsic diseases of myocardium characterized by principal cardiac dysfunction

Question 2

What are the two general types of causes of cardiomyopathies?

Answer 2

Genetic, and acquired.

Question 3

What is the difference between primary and secondary cardiomyopathies?

Answer 3

Primary cardiomyopathies are diseases solely or predominantly confined to the heart muscle, where as secondary cardiomyopathies or when the heart is part of a generalized multi organ disorder.

Question 4

What are the three categories of the cardiomyopathies?

Answer 4

Dilated (most common), hypertrophic, restrictive

Question 5

What is the most common form of cardiomyopathy?

Answer 5

Dilated

Question 6

Describe dilated cardiomyopathy.

Answer 6

Progressive hypertrophy and dilation of all four chambers leading to systolic failure.

Question 8

Name seven potential causes of dilated cardiomyopathy.

Answer 8

Infection/myocarditis, drugs like anthracyclines such as doxorubicin, toxins, metabolic disorders, neuromuscular disorders, childbirth, genetics.

Question 9

______% of cases of dilated cardiomyopathy are familial, mostly autosomal dominant, affecting genes that encode cytoskeletal/sarcomere/microtubule proteins like titin/connectin, TNN.

Answer 9

25-35%

Question 10

In what age range is dilated cardiomyopathy most often seen?

Answer 10

25-50 year olds

Question 11

In end-stage dilated cardiomyopathy, the ejection fraction is typically less than _____% of normal.

Answer 11

less than 25% of normal

Question 12

Only ____% of patients with dilated cardiomyopathy survive for two years and only ____% survive for five years or longer.

Answer 12

50, 25

Question 13

What is the definitive treatment for dilated cardiomyopathy?

Answer 13

Cardiac transplantation.

Question 14

Describe the morphological changes associated with dilated cardiomyopathy.

Answer 14

Enlarged heart 3 to 4 times the normal size, flabby, with dilation of all four chambers.

Question 15

Are mural thrombi common and dilated cardiomyopathy? What is the biggest complication from the mural thrombus?

Answer 15

Yeah common, thromboemboli is the complication.

Question 16

Is coronary artery occlusion common in dilated cardiomyopathy?

Answer 16

Nope

Question 17

What microscopic morphological changes are common in cardiomyopathy?

Answer 17

Hypertrophied myocytes with enlarged nuclei, other myocytes show signs of degeneration; variable interstitial and endocardial fibrosis.

Question 18

In hypertrophic cardiomyopathy, the hypertrophy is out of _______ compared to the hemodynamic load.

Answer 18

proportion

Question 19

In hypertrophic cardiomyopathy there is disproportionate thickening of the left part of ventricular septum, causing the chamber to be ________ shaped. This is also known as ____ _____ ______.

Answer 19

banana. aka assymetrical septal hypertrophy

Question 20

In hypertrophic cardiomyopathy, concentric hypertrophy is seen in ____% of cases.

Answer 20

10

Question 21

What causes hypertrophic cardiomyopathy?

Answer 21

Autosomal dominant missense gene mutations in one or more genes encoding sarcomeric proteins such as in the Beta myosin heavy chain.

Question 22

Describe the myofiber orientation in hypertrophic cardiomyopathy.

Answer 22

Disarray; not parallel, branches running in all directions

Question 23

What is the main cause of death in young athletes with hypertrophic cardiomyopathy?

Answer 23

Arrhythmias

Question 24

Restrictive cardiomyopathy is characterized by a primary decrease in ventricular ________, resulting in impaired ______.

Answer 24

compliance resulting in impaired filling

Question 25

What is the least common type of cardiomyopathy?

Answer 25

Restrictive

Question 26

What is the only histologic abnormality in restrictive cardiomyopathy?

Answer 26

Interstitial fibrosis

Question 27

What disease does restrictive cardiomyopathy invariably progress to?

Answer 27

Congestive heart failure

Question 28

Name four causes of restrictive cardiomyopathy.

Answer 28

1. Interstitial infiltration of amyloid. 2. Endomyocardial diseases. 3. Storage diseases like hemochromatosis 4. Markedly increased interstitial tissue

Question 29

How does amyloid stain with Congo red stain?

Answer 29

It stains apple-green in cross-polarizing light.

Question 30

Describe the gross morphological changes of restrictive cardiomyopathy.

Answer 30

Ventricles are normal size, maybe slightly enlarged, cavities are not dilated, myocardium is firm.

Question 31

What is myocarditis?

Answer 31

Inflammation of the myocardium with myocyte necrosis and degeneration. Inflammation is the primary cause of the disease.

Question 32

In what population has myocarditis most common?

Answer 32

Children 1-10 years old

Question 33

What are the two major complications of myocarditis?

Answer 33

1. acute biventricular heart failure in previously healthy children/young adults. 2. Arrhythmias --> sudden cardiac death (SCD)

Question 34

What are the three causes of myocarditis?

Answer 34

1. Viral 2. Non-viral infections 3. Hypersensitivity/immunological.

Question 35

What are the major causes of myocarditis?

Answer 35

1. Viral infections, mostly coxsackieviruses (injury is due to immune response agaist virally-infected myocardial cells). 2. Non-viral organisms such as Trypanosoma cruzi (causative agent for Chagas disease), Trichinosis, Borrelia burgdorferi (Lyme disease).

Question 36

What are the four types of myocarditis?

Answer 36

1. Lymphocytic myocarditis 2. Hypersensitivity myocarditis 3. Giant cell myocarditis 4. Chagas disease

Question 37

What morphological changes are characteristic of Lymphocytic myocarditis?

Answer 37

Infiltrate of mononuclear inflammatory cells with diffuse myocardial degeneration and necrosis.

Question 38

What morphological changes are characteristic of Hypersensitivity myocarditis?

Answer 38

Interstitial inflammatory infiltrate of eosinophils and monocytes with diffuse myocardial degeneration and necrosis.

Question 39

What morphological changes are characteristic of Giant cell myocarditis?

Answer 39

Mononuclear inflammatory cells with lymphocytes and macrophages, extensive muscle loss, and multinucleated giant cells.

Question 40

Where is Chagas disease most common? What is the treatment?

Answer 40

South America, no Tx

Question 41

What is a myxoma?

Answer 41

A benign primary neoplasm of the heart.

Question 42

Myxomas are often associated with clonal abnormalities of chromosomes 12 and 17 and are thought to arise from primitive multipotent _________ cells.

Answer 42

mesenchymal

Question 43

_____% of myxomas arise in the left atrium as a glistening, gelatinous, polypoid mass 5-6cm in diameter with a short stalk.

Answer 43

75

Question 44

Myxomas have a loose myxoid stroma (clear jelly-type crap) of stellate or globular myxoma cells embedded within a background of abundant ________.

Answer 44

proteoglycans.

Question 45

Do myxomas often form peculiar vessel-like or gland-like structures?

Answer 45

Yeah!

Question 46

How can a myxoma cause death?

Answer 46

Embolus --> stroke

Question 47

The normal amount of fluid in the pericardium is 30-50 ml but in pericardial disease there can be up to ______ ______ ml in the pericardium.

Answer 47

several hundred ml

Question 48

Pericardial disease can cause cardiac tamponade. What is that?

Answer 48

It is when the effusion restricts the heart from filling.

Question 49

Name five possible causes of pericardial effusion. Which one is most likely after a MI?

Answer 49

1. Trauma 2. Dissecting aorta 3. Vessel infiltration by a tumor 4. Cardiac wall rupture (after MI) 5. Bleeding diathesis (hypocoagulability)

Question 50

What is hemopericardium? After what type of event can this occur?

Answer 50

Bleeding into the pericardium - can happen after a MI

Question 51

Describe the three general types of pericarditis.

Answer 51

1. Fibrinous: Exudate effusion rich in monocytic inflammatory cells and collagen. Seen in acute MI, uremia, chest radiation, rheumatic fever, and trauma. 2. Purulent/supperlative pericarditis: From invasion of the pericardial space by microbes. Acute inflammation often leads to organization and scarring. 3. Constrictive - a potential result of purulent pericarditis.

Question 52

When during embryonic development do the major cardiovascular structures form?

Answer 52

3-8 weeks.

Question 53

Congenital heart diseases are seen in approximately ___% of live births.

Answer 53

1

Question 54

What type of congenital heart disease is most common?

Answer 54

Left-to-right shunt

Question 55

Name three types of left-to-right shunts. Which one is most common?

Answer 55

1. Ventricular septal defect (VSD) - 40% 2. Atrial septal defect - 10% 3. Patent ductus arteriosus (PDA) - 7%

Question 56

Which type of left-to-right shunt is associated with increased pulmonary blood volumes?

Answer 56

Atrial septal defect

Question 57

Which type of left-to-right shunt is associated with increased pulmonary blood pressure and flow?

Answer 57

VSD

Question 58

Cyanosis is characteristic of what type of heart shunting?

Answer 58

Right-to-left only.

Question 59

What are the two most common congenital heart diseases that are right-to-left shunts?

Answer 59

Tetralogy of Fallot and transposition of the great arteries.

Question 60

Clubbing of the fingertips and polycythemia (increased RBCs/blood volume) is characteristic of which congenital heart disease?

Answer 60

Tetralogy of Fallot

Question 61

What is a paradoxical embolism?

Answer 61

A venous embolism that passes through a right-to-left shunt and causes a stroke.

Question 62

What are the four anatomical abnormalities seen in Tetralogy of Fallot?

Answer 62

1. VSD 2. Pulmonary valve (subpulmonic) stenosis 3. Overriding aorta 4. RV hypertrophy

Question 63

What causes cyanosis in patients with Tetralogy of Fallot?

Answer 63

The pulmonary stenosis forces blood from the RV to pass into the LV and mix with oxygenated blood, causing O2 desaturation

Question 64

What two other diseases are patients with Tetralogy of Fallot at risk for?

Answer 64

Bacterial endocarditis and brain abscesses.

Question 65

What is transposition of the great arteries?

Answer 65

When the aorta arises from the RV and the pulmonary artery arises from the LV

Question 66

What compensatory anatomical abnormalities usually co-exist with transposition of the great arteries?

Answer 66

Atrial or ventricular septal defect or patent ductus arteriosus.

Question 67

What is aortic coarctation? How common is it?

Answer 67

A constriction of the aorta at the ductus arteriosus. Makes up 7% of congenital heart diseases.

Question 68

In which gender is aortic coarctation 2-5 times more common?

Answer 68

Males

Question 69

Describe the blood pressure discrepancy seen in aortic coarctation.

Answer 69

1. Upper body is hypertensive, results in LV hypertrophy | 2. Lower body is hypotensive, leads to weakness, pallor, and lower extremity coldness.

Question 70

What causes notching of the inner surfaces of the ribs in patients with aortic coarctation?

Answer 70

Intercostal arteries, which branch off the aorta proximal to the coarctation become dilated due to the increased pressure and flow. These dilated arteries pulse with the heartbeats and notch the ribs.