Cardiomyopathies 2

Question 1

sarcoidosis restrictive cardiomyopathy (cardiac sarcoid) - overview

Answer 1

*noncaseating sarcoid granulomas can deposit in the heart, causing whitish tissues (sarcoid) and an associated scar
*characterized by the presence of non-caseating granulomas on histology

Question 2

prevalence of cardiac sarcoidosis

Answer 2

*only 5% of people with sarcoidosis have CLINICAL evidence of cardiac involvement, but on autopsy 70% have cardiac involvement
*most likely symptom/clinical manifestation of cardiac sarcoidosis = VENTRICULAR TACHYCARDIA

Question 3

echo findings of clinical sarcoidosis

Answer 3

*thin LV septum
*thin LV wall
*ventricular aneurysms, particularly in the inferolateral wall
*systolic dysfunction with LV dilation

Question 4

Loeffler’s Endocarditis / Endomyocardial Fibrosis - causes

Answer 4

*eosinophilic states that may result in Loeffler’s endocarditis include:
-hypereosinophilic syndrome
-eosinophilic leukemia
-carcinoma
-lymphoma
-drug reactions
-parasites

Question 5

Loeffler’s Endocarditis / Endomyocardial Fibrosis - pathogenesis

Answer 5

*eosinophilia & eosinophilic penetration of the cardiac myocytes leads to a fibrotic thickening of the endocardium
*commonly, the heart will develop large mural thrombi (thrombi which lay against the ventricle walls) due to deterioration of LV wall muscle contractility

Question 6

Loeffler’s Endocarditis / Endomyocardial Fibrosis - symptoms

Answer 6

*edema
*breathlessness
*the disease is commonly contracted in temperate climates (due to favorable conditions for parasites)
*rapidly fatal

Question 7

Fabry’s Disease - overview

Answer 7

*an X-linked disease of lysosomal metabolism, resulting in attenuated activity or, in most males, absence of the enzyme alpha-galactosidase A (alpha-Gal A)
*as a result, the breakdown of glycosphingolipids is impaired, leading to systemic lysosomal accumulation of Gb3

Question 8

Fabry’s Disease - diagnosis

Answer 8

*enzyme assay (usually done on leukocytes) to measure the level of alpha-galactosidase activity

Question 9

Fabry’s Disease - symptoms

Answer 9

*cardiac complications
*peripheral neuropathy
*renal complications
*GI motility

Question 10

Fabry’s Disease - imaging/EKG

Answer 10

*EKG findings: symmetrical T-wave inversion across the prochordium
*echo: muscle function normal but thickened wall
*coronary angiography shows that the coronaries are wide open
*cardiac MRI: thickened muscle; deposition of Gb3

Question 11

hemochromatosis - overview

Answer 11

*characterized by an accelerated rate of intestinal iron absorption and progressive iron deposition in various tissues
*most common presentation is hepatic cirrhosis, in combination with: hypopituitarism, cardiomyopathy, diabetes, arthritis, hyperpigmentation
*autosomal RECESSIVE trait

Question 12

iron deposition cardiomyopathy (due to hemochromatosis)

Answer 12

*deposition of iron in the cardiac muscle, leading to a restrictive cardiomyopathy
*heart is dilated due to iron deposition
*treatment with phlebotomy allows the heart to remodel back to normal shape

Question 13

hypertrophic cardiomyopathy (HCM) - overview

Answer 13

*abnormal muscle thickness without increased afterload (i.e. hypertension or aortic stenosis) due to a GENETIC ABNORMALITY, most likely with the SARCOMERE
*characterized by myocyte disarray
*affects 1 in 500 people

Question 14

hypertrophic cardiomyopathy vs. concentric left ventricular hypertrophy

Answer 14

*hypertrophic cardiomyopathy: genetic; REGIONAL LV wall thickening

*concentric LVH: due to pressure overload (aortic stenosis, HTN); GLOBAL LV wall thickening

Question 15

hypertrophic cardiomyopathy - histology

Answer 15

*disarray in the arrangement of the myocytes relative to normal myocytes

Question 16

genetics of hypertrophic cardiomyopathy

Answer 16

*genetic mutations associated with the SARCOMERE, such as: myosin binding protein C and beta-myosin heavy chain

Question 17

hypertrophic cardiomyopathy - types

Answer 17

1. asymmetric septal hypertrophy without resting murmur
2. obstructive hypertrophic cardiomyopathy, associated with the classic murmur (this is the type we are usually referring to)
3. mid-ventricular HCM with associated apical aneurysm
4. apical HCM

Question 18

obstructive hypertrophic cardiomyopathy & Venturi Effect

Answer 18

*very thick septum can lead to abnormal motion of mitral valve during systole
*mitral valve gets sucked toward the septum, obstructs flow into the aorta

Question 19

hypertrophic cardiomyopathy - symptoms

Answer 19

*dyspnea
*angina (chest pain)
*syncope
*sudden death
*S4 SYSTOLIC MURMUR

Question 20

therapy for LVOT obstruction in hypertrophic cardiomyopathy

Answer 20

*medical therapies:
-disopyramide (Na+ blocker)
-beta-blockers
-verapamil (Ca blocker)
-mavacamten

*if not relieved by medical therapy, options:
1. alcohol septal ablation (once balloon inflated, infuse alcohol, which causes infarction of the thickened portion of the septum)
2. surgical myectomy (removal of excess myocardial tissue)

Question 21

hypertrophic cardiomyopathy - clinical manifestations

Answer 21

*myofibrillar disarray → increased risk of ventricular arrhythmias (es. ventricular tachycardia) → sudden cardiac death

Question 22

hypertrophic cardiomyopathy & sudden cardiac death risk factors

Answer 22

*prior cardiac arrest
*family members with sudden death caused by HCM
*unexplained syncope
*non-sustained ventricular tachycardia
*patients whose blood pressure falls during exercise
*extreme thickness of left ventricular wall (33 mm or more)

Question 23

arrhythmogenic right ventricular cardiomyopathy (ARVC) - overview

Answer 23

*inherited disease involving FIBROFATTY REPLACEMENT of the right ventricle myocardium leading to conduction abnormalities and arrhythmias
*primary risk is that it can induce malignant ventricular arrhythmias → sudden cardiac death
*if certain criteria met, need ICD
*no cure
*epsilon wave on EKG

Question 24

“unclassifiable” cardiomyopathies

Answer 24

1. Takotsubo cardiomyopathy (stress-induced cardiomyopathy)
2. left ventricular noncompaction cardiomyopathy

Question 25

Takotsubo cardiomyopathy (stress-induced cardiomyopathy) - typical presentation

Answer 25

*emotional malady/intense feelings can cause the HEART TO CHANGE SHAPE
*ventricular apical ballooning likely due to INCREASED SYMPATHETIC STIMULATION (i.e increased release of catecholamines)
*often precipitated by emotional stress, but can be instigated by physiologic stress as well (surgery, trauma, illness)
*with the apical involvement, you worry about the left anterior descending artery, but it’s completely open

Question 26

Takotsubo cardiomyopathy (stress-induced cardiomyopathy) - treatment

Answer 26

*supportive care
*perhaps tx with beat blocker to protect from over-stimulation by epinephrine or norepinephrine
*expect 100% recovery

Question 27

left ventricular noncompaction cardiomyopathy

Answer 27

*noncompacted layer of cardiac tissue; significant trabeculations; muscle function is poor
*REFRACTORY CHF, VENTRICULAR TACHYCARDIA, and STROKES occurring in young individuals were the 3 things that demarcated this condition
*ventricular tachycardia because some of these tissues conduct electricity
*typically seen in younger individuals
*complications include cardiac shock, pulmonary edema, stroke