Cardiology - Pericarditis and Myocarditis Flashcards
How does myocarditis typically present?
- young and acute
- heart failure over days/weeks with dyspnoea and chest pain
- ECG abnormalities and elevated troponins
What are the indications for biopsy in myocarditis?
- ventricular arrythmias
- high grade conduction block
- lack of response to usual HF treatment
What is the DALLAS criteria?
The histological criteria for myocarditis
= inflammatory cellular infiltrate PLUS myocyte necrosis
Management of myocarditis?
HF medications
Usually no mortality/EF benefit with steroids
How long should you wait before deciding to ICD implant post myocarditis?
6 months
What are the viral causes of myocarditis?
RNA viruses: enterovirus / Coxsackie / echovirus
DNA viruses: adenovirus / herpesviruses / HHV6 / parvovirus B19 (MOST COMMON)
HIV
Hep C
What are the parasitic causes of myocarditis?
Chagas (T cruzi)
- acute phase in <5% with acute myocarditis / meningoencephalitis
- over 10-30 years develop conduction block, AF and dilated cardiomyopathy
African Trypanosomiasis
- T brucei rhodesiense: RAPID myocariditis and heart failure
- T brucei gambiense presents GRADUAL HF over years
Toxoplasmosis
- also assoc: encephalitis / chorioretinitis / pericarditis and myocarditis / heart failure
Trichinellosis:
- assoc: myalgias, fever, weakness, periorbital/facial oedema
- eosinophilic inflammation
How does African Trypanosomiasis present as a cause of myocarditis?
- T brucei rhodesiense: RAPID myocariditis and heart failure
- T brucei gambiense presents GRADUAL HF over years
What are the bacterial causes of myocarditis?
Diphtheria
Clostridium
** produce a toxin that damages myocytes
What are the inflammatory causes of myocarditis?
Sarcoidosis
Giant Cell Myocarditis
Eosinophilic myocarditis
(can be idiopathic or associated with eosinophilic syndromes)
Hypersensitivity myocarditis
Features of sarcoidosis myocarditis?
- pulm sarcoid has higher risk
- steroid treatment is more effective for arrhythmias than HF
How does Giant Cell Myocariditis present?
Acute rapidly progressive HF with tachyarrythmias
Usually in patients <40yrs old
Assoc:
- thymoma
- thyroiditis
- pernicious anaemia
Treat with cardiac transplant
PLUS some improved survival with aggressive steroids
What does the biopsy in hypersensitivity myocarditis show?
Lymphocytes and mononuclear cells with eosinophilia
What drugs are associated with hypersensitivity myocarditis?
Thiazides
Anticonvulsants
Indomethasin
Methyldopa
What drugs can cause myocarditis?
Doxorubicin
