Pathology of Myocarditis

Question 1

Myocarditis Definition

Answer 1

Primary inflammatory process causes myocardial injury

Question 2

Myocarditis vs. Infectious Heart Disease

Answer 2

Myocarditis is group of pathological entities in which infectious micro-organisms and/or primary inflammatory process cause myocardial injury.

Question 3

What are the various causes of myocarditis ?

Answer 3

viral, bacterial, parasitic/fungal, other

Question 4

Coxsackie B Virus Pathology

Answer 4

Coxsackie virus is small, acid stable RNA virus, and is widely present in the environment, fecal/oral route transmission, male children affected

Hand-foot, and mouth disease, aonjunctivitis, myocarditis, pericarditis, ect. Meningitis

Question 5

Coxsackie B Seasonality

Answer 5

50% of specimen type collected in the lab.

Serology: real time RT-PCR is the main method

June-October: 80% of the viruses

Question 6

Myocarditis symptoms

Answer 6

EKG–> sinus arrythmia with ST-T wave changes

History and Physical Exam suggestive of heart failure

Troponin and creatine kinase elevated

MRI can visualize tissue changes

Question 7

Gross changes in Acute Myocarditis

Answer 7

Heart may appear normal, dilated, flabby

mural thrombi

interstitial inflammation associated with focal myocyte necrosis

acute phase survival

Question 8

Amyloid

Answer 8

Are fibrillar proteins and a beta secondary structure (cross perpendicular to

Question 9

Management and Prognosis of Myocarditis

Answer 9

5%- 20% of sudden death in young adults

Patients who survive acute fulminant myocarditis have reasonably good prognosis

Management: reduce congestion and improve heart failure

Cardiac Transplants

Question 10

Parasite Trypanosoma Cruzi

Answer 10

causes Chagas disease and is spread by feces of the Reduviid bug.

Question 11

Management and Prognosis of Myocarditis

Answer 11

5%-20% of sudden death in young adults

Patients who survive acue have reasonably good prognosis but recurrent infections

Question 12

Chagas disease micro-pathology features:

Answer 12

pseudocysts + mixed inflammatory response of neutrophils, lymphocytes, macrophages, and eosinophils

Question 13

Amyloid

What is the characteristic

Answer 13

Starch like proteins

Stained with Congo-Red dye exhibits apple-green birefringence under polarized light.

Question 14

Amyloid protein types:

Answer 14

1. AL –> cardiac
2. AA –> liver
3. B-amyloid Protein –> core of cerebral plaques in alzheimer’s disease and cerebral blood vessels
4. ATTR –> organs, heart, and endocrine

Question 15

Clinical Presentation of Cardiac Amyloid

Answer 15

Gross Pathology of the amyloid heart can be normal, firm, or rubbery.

Question 16

Cardiac Amyloidosis Features

Answer 16

1. Histopathology shows Congo-red stain viewed under polarized light microscopy
2. always between muscle fibers
3. Atrophy and toxicity of muscle fibers
4. Lev’s syndrome: EKG abnormalities and conduction system defects

Question 17

Pericarditis

Answer 17

Primary Pericarditis is unusual and usually of viral origin.

Question 18

Types of Pericarditis:

Answer 18

1. Purulent or suppurative pericarditis: Active infection such as empyema of the pleural cavity.
2. Constrictive pericarditis: healed pericarditis may follow infectious type. Cardiac dilation and hypertrophy do not occur because of the scarring.

Question 19

What is pathology of fibrinous pericarditis?

Answer 19

Dry surface, granular, roughening. “Bread and Butter” is charactersitic gross appearance.

Question 20

Cardiac Myxoma

Answer 20

Most frequent cardiac tumor in adults. 2nd most frequent in children, second to rhabdomyoma.

Bland spindle cells, contains numerous blood vessels.

Usually do not undergo malignant transformation

Numerous blood vessels and usually do not undergo malignant transformation.

Question 21

Rhabdomyolysis

Answer 21

Tuberous Sclerosis

80% of fetuses with rhabdomyomas will have tuberous sclerosis