Myocarditis - intrinsic Flashcards
What is myocarditis?
clinically & pathologically defined as:
- inflammation of the myocardium
- in the absence of:
- the predominant acute / chronic ischaemia characteristic of coronary artery disease.
- It is a clinical syndrome of non-ischaemic myocardial inflammation resulting from a heterogeneous group of infectious, immune, and non-immune diseases
What is the histopathological definition of myocarditis?
- inflammatory cellular infiltrate
- with / without evidence of myocyte injury
What is the cause of myocarditis?
infectious:
- viral
- bacterial
- Spirochetal
- myocytic
- Protozoal
- Rickettsial
- Q fever
- Rocky mountain spotted fever
non- infectious
- Toxins/drug related
- Hypersensitivity
- Systemic disorders
Name some viruses that can cayse myocarditis
- Influenza A and B
- Adenovirus
- Coxsackie B virus
- Dengue
- Hepatitis B and C virus
- Mumps
- Rubella
- Rubeola
- HIV
- Echovirus
- Epstein-Barr virus
- Cytomegalovirus
- Parvovirus
- Herpes simplex virus
- Poliomyelitis
- Rabies
- Varicella
Name some bacteria that can cause myocarditis
- Mycobacterial
- Streptococcal species
- Mycoplasma pneumoniae
- Treponema pallidum
- Tuberculosis
- Staphylococcal species
- Clostridium species
- Neisseria gonorrhea
Name some spirochetal causes of myocarditis
- Lyme disease
- Leptospirosis
- Syphilis
Name some mycotic causes of myocarditis
- c species
- Candida species
- Coccidiomycosis
- Cryptococcus species
- Histoplasma species
- Sporotrichosis species
- Blastomycosis
Name some protazoal causes of myocarditis
- Trypanosoma cruzi (Chagas’ disease)
- African trypanosomiasis (sleeping sickness)
- Toxoplasmosis
- Malaria
- Parasitic
- Schistosomiasis
- Larva migrans
Name some toxins/drugs that can cause myocarditis
- Anthracyclines
- Arsenic
- Carbon monoxide
- Ethanol
- Iron
- Interleukin-2
- Cocaine
- Smallpox vaccination
- Catecholamines (e.g., adrenaline, noradrenaline, dopamine)
- Cyclophosphamide
- Heavy metals (copper, iron, lead)
Name some hypersensitivity causes of myocarditis
- Antibiotics (penicillins, cephalosporins, sulfonamides, amphotericin B)
- Thiazide diuretics
- Antiepileptics (carbamazepine, phenytoin, phenobarbital)
- Digoxin
- Lithium
- Amitriptyline
- Dobutamine
- Snake bites
Name some systemic causes of myocarditis
- Collagen-vascular diseases
- IBD
- Giant cell myocarditis
- Diabetes mellitus
- Sarcoidosis
- Thyrotoxicosis
- Granulomatosis with polyangiitis (formerly known as Wegener’s granulomatosis)
- Loeffler’s syndrome
What are the risk factors for myocarditis?
-
infection
- actual organism varies nationally, but worldwide: Trypanosoma cruzi
- HIV
- smallpox vaccine
- autoimmune/immune-mediated diseases
- peripartum and postnatal periods of life
- drugs use & toxins
Summarise the epidemiology of myocarditis
sudden cardiac death in young adults suggests myocarditis as the aetiology in approximately 10% of cases
in dilated cardiomyopathy, myocarditis is the aetiology in 9% of patients
What are the presenting symptoms of myocarditis?
Prodromal flu-like illness with:
- Fever
- Malaise
- Fatigue
- Lethargy
- dyspnoea
- (due to pericardial effusion/myocardial dysfunction)
- palpitations
- sharp chest pain
- (suggesting there is also pericarditis)
What other symptoms are present when myocarditis manifests as new-onset congestive heart failure (CHF) ?
- orthopnoea
- rales
- elevated neck veins
- S3 gallop
- sinus tachycardia
