8.6 Cardiomyopathy

Question 1

most common type of cardiomyopathy

Answer 1

dilated cardiomyopathy

Question 2

types of cardiomyopathies, and how they’re different

Answer 2

1. Dilated–all chambers enlarge. systolic dysfunction
2. Hypertrophic–heart walls thicken, making walls stiffer. diastolic dysfunction
3. Restrictive–heart walls stiffen (not necessarily thicken), diastolic dysfunction

Question 3

dilated cardiomyopathy

-complications (3)

Answer 3

1. systolic dysfunction, so both sided heart failure
2. mitral and tricuspid regurg b/c stretched heart walls pull valves apart
3. arrythmias from wall stretch

Question 4

dilated cardiomyopathy

• causes (6)
• which is most common cause
• what infection is associated

Answer 4

1. idiopathic (most common)
2. myocarditis (usu Coxsackie)
3. Alcohol abuse
4. Drugs
5. Pregnancy
6. Hemochromatosis

Question 5

hypertrophic cardiomyopathy

-main cause

Answer 5

-auto dom genetic mutation in sarcomeres

Question 6

hypertrophic cardiomyopathy

-what do you see on histology?

Answer 6

-myofiber disarray–myocytes are not parallel but random directions

Question 7

Myocarditis

-what do you see on histology

Answer 7

• lymphocyte infiltration of myocardium
• eg Coxsackie infection, which can lead to dilated cardiomyopathy

Question 8

hypertrophic cardiomyopathy

-clinical features/complications (3)

Answer 8

1. diastolic dysfunction–decreased CO
2. Sudden death from ventricular arrythmias
3. Syncope with exercise (functional aortic stenosis from hypertophy of LV septum)

Question 9

Restrictive cardiomyopathy

-main causes (4)

Answer 9

1. amyloidosis
2. sarcoidosis
3. endocardial fibroelastosis (stiffened endocardium, in children)
4. Loeffler syndrome (both endo and myocardial layers fibrose)

Question 10

How does Restrictive cardiomyopathy present on EKG

Answer 10

-classic finding of low-voltage EKG with diminished QRS amplitude