Flashcards in Myocarditis and other Cardiac Disease Deck (16):
What is the most common cause of myocarditis in the US?
Coxsackie virus A and B (more B)
What causes myocarditis more in South America?
Chaga's disease= trypanosoma cruzi
What else can cause myocarditis?
- neisseria, borrelia (lyme), or candida albicans
- sarcoidosis, SLE, drugs, radiation
What will we see in the heart with myocarditis?
soft focal hemorrhage, mononuclear cell infiltrate (if viral), neutrophil infiltrate (if bacterial), or necrosis.
What is giant cell myocarditis?
Has giant cells but also eosinophils, plasma cells, macrophages, and lymphocytes leading to extensive necrosis. Poor prognosis with rapid and lethal clinical course.
Does hypersensitivity myocarditis tend to occur in older or younger people?
older, and associated with drug hypersensitivity such as methyldopa. Will see large numbers of eosinophils.
What do you see in cardiac sarcoidosis and how do you distinguish it from giant cell myocarditis?
giant cells and noncaseating granulomas, but you won't see eosinophils or necrosis.
What will you see in lymphocytic myocarditis?
lots of lymphoctyes
How do pts present with myocarditis?
most are asymptomatic and will be self limiting. Others however may have lethal arrhythmias or develop into dilated cardiomyopathy.
What is arrhythmogenic right ventricular dysplasia?
inherited disease causing right ventricular failure and rhythm disturbances (ventricular tachycardia or fibrillation) and can lead to sudden death (especially in young people).
It is related to defective cell adhesion proteins in the desmosomes that link adjacent cardiac myocytes causing thin right ventricle.
What drugs have been linked to myocardial injury?
cocaine, lithium, phenothiazides, and chloroquine. Also chemo and immunotherapy drugs.
Can intense catecholamine (vasopressor) stimulation cause myocardial damage?
YES. Also pheochromocytoma can cause this.
What does amyloidosis do to the myocardium?
deposition of insoluble extracellular fibrillar material forming beta-pleated sheets. Senile (deposition of transthyretin) has better prognosis than systemic amyloidosis.
Looks like amorphous pink material around the myocytes.
****How do we stain for amyloidosis?
congo red, which produces an apple green birefringence.
What causes iron overload?
hemochromotosis or multiple blood transfusions.