Non-Ischaemic Myocardial Disease Flashcards
What is a cardiomyopathy
Any disease of the cardiac muscle that is not ischaemic, hypertensive
What changes may cardiomyopathy cause?
Changes in size of chamber walls
What are the four classifications of cardiomyopathy?
Dilated
Hypertrophic
Restrictive
Arrhythmogenic right ventricular dysplasia
Describe dilated cardiomyopathy?
Weak and flabby heart
Bigger than it should be may only be by 50g though
What are the histological features of dilated cardiomyopathy?
none
What are the causes of dilated cardiomyopathy?
50% genetic toxins -alcohol -doxorubicin (chemo) cardiac infection pregnancy
What are the clinical features of DCM?
General heart failure
Describe hypertrophic cardiomyopathy?
Big solid heart
Strong contraction
Heart doesn’t relax as it should
What does hypertrophic cardiomyopathy cause?
Outflow obstruction
Sudden death
What are the causes of HCM?
Genetic
Actin or myosin mutated genes
beta myosin heavy chain
What is the appearance of HCM?
RV and RA look normal
LA may be dilated
LV will be extraordinarily thick- normally 15mm, may be 4cm
Coronary Arteies are not increased and therefore there must be areas of relative hypoxia or ischaemic- possibly angina
What is the histology of HCM?
Myofibres will be disorganised (swirls-myofibre disarray) as opposed to linear
Describe restrictive cardiomyopathy?
Lack of compliance
Stiff heart
Doesn’t fill well- diastolic dysfunction
Can’t generate a sufficient stroke volume to generate BP
Bi-atrial dilatation as a result of back pressure
What does RCM look like histologically?
Normal
What are the causes of RCM?
>Deposition of something in the myocardium >metabolic by-products (iron) >amyloidosis >sarcoidosis >tumour >fibrosis
Describe amyloidosis
o abnormal deposition of an abnormal protein throughout the body
o lots of different types of protein- lots of types of amyloid
o tendency to form beta-pleated sheets
o body cannot get rid of them
What kind of amyloidosis is isolated to the heart?
Senile cardiac amyloidosis
What kind of amyloidosis may be isolated to the atrium?
Abnormal atrial natriuretic protein
What is the appearance of amyloidosis on histology?
o waxy pink material
o eosinophilic
o exhibits apple green birefringence
o stains positively for Congo red
What does amyloid generally resemble?
RCM
What is arrhythmogenic right ventricular dysplasia?
> Right ventricle becomes largely replaced by fat
>Big and floppy
What does ARVD look like histologically?
only a tiny bit of myocardium and muscle is replaced by adipocytes
What is the cause of ARVD?
Genetic
What is myocarditis?
Inflammation of the heart
What are the types of myocarditis?
Infectious vs non infectious
Bacterial, viral, fungal, protozoal and helminthic
What is the most common type of myocarditis?
Infectious
What are the causes of infectious myocarditis?
- Coxsakie A and B
- ECHO virus
- chaga’s disease- trypanosomiasis in S. America
- borrelia burgdorferi- Lyme’s disease
- HIV
What does the myocardium look like in infectious myocarditis?
Thick and beefy
What might you see on biopsy of infectious myocarditis?
Inflammatory infiltrate
What are the causes of non-infectious myocarditis?
> Immune mediated hypersensitivity disorders
hypersensitivity to infection
hypersensitivity to drugs
SLE
Describe hypersensitivity to infection in myocarditis?
rheumatic fever after strep sore throat
o classic mitral stenosis with thickening and fusion of valve leaflets
o short, thick chordae tendinae
o myocardium is also patchily inflamed
o fibrotic scarring will effect heart valves and give you mitral stenosis
What will you see histologically in myocarditis caused by hypersensitivity to infection?
o histologically- aschoff bodies, central destructive region which peppers the heart valves
What is pericarditis?
Inflammation of the pericardial layers
Outer layers of the heart become inflamed
What are the causes of pericarditis?
Infectin Immune related Idiopathic Uraemic Post MI SLE
What is post MI pericarditis?
Dressler’s syndrome
- abnormal response to dead cells
- many weeks post MI
Which virus produces serious effusion in pericarditis?
ECHO
What is the common cause of bacterial pericarditis?
extension from elsewhere, pneumonias, produce purulent effusions
Who gets fungal pericarditis?
immunosuppressed pts, post-transplant (bone marrow for example), produce purulent effusions
What are the complications of pericarditis?
>pericardial effusion >tamponade >constrictive pericarditis >cardiac failure >death
Describe constrictive pericarditis?
- fibrotic response to inflammation on surface of the heart
- wherever there is fibrosis there is collagen, which contracts and cause a contracture, strangling the heart from the inside
What is endocarditis?
inflammation of the inside of the heart lining generally referring to the inflammation of the valves
Where does infective endocarditis occur?
can occur at normal valves
What does infective endocarditis usually require?
A very virulent organism
What are the most common causes of infective endocarditis now?
prosthetic valves, congenital defects, bicuspid valves, MV prolapse, calcific disease in the elderly
What are the HACEK organisms?
Organisms of endocarditis
- haemophilus
- aggregatibacter
- cardiobacterium
- eikenella corrodens
- kingella king
What is the pathology of IV drug users?
Right sided valves
Which organism is common in prosthetic valves?
S. epidermidis
What is a vegetation
aggregates of organisms on heart valves
What are some common signs of endocarditis?
- oslers nodes
- janeway lesions
- roth spots
- splinter haemorrhages
- septicaemia
What is non-infectious endocarditis?
Marantic
What is non-bacterial thrombotic endocarditis?
Smaller
What is non-bacterial thrombotic endocarditis associated with?
cancers
o mucinous adenocarcinomas
What is found on the valves in non-bacterial thrombotic endocarditis ?
Small and multiple vegetation
non-invasive and don’t destroy valves
When is non-bacterial thrombotic endocarditis common?
In hyper-coagulable states
What kind of endocarditis occurs in lupus?
Libman-sacks endocarditis
What are the symptoms of Libman-sacks endocarditis?
Often asymptomatic
What kind of emboli are found in Libman-sacks endocarditis?
Small sterile emboli
What is carcinoid heart disease?
Neuroendocrine cancer
can see them in any mucosa- common in GI and lung
Where do carcinoid tumours metastasise to?
The liver
What kind of heart disease does carcinoid heart disease produce?
Right sided cardiac valve disease
Tricuspid and pulmonary insufficiency
What is the commonest heart tumour?
Atrial myxoma is the commonest primary
Where is atrial myxoma found?
sits just above the mitral valve
Is atrial myxoma benign?
Yes but can produce clinical pathology that is just as bad as malignancy
What is a side effect of atrial myxoma?
Myxoid tumour emboli
May develop endocarditis
Systemic fever and malaise, IL-6
Potential secondary
Where are atrial myxoma found?
90% in atria, usually left
