Cardiomyopathy Flashcards
what is a cardiomyopathy
a disease affecting the cardiac muscle
what does a cardiomyopathy often result in
changes in the size and thickness of the heart chambers
describe the pathological and histological features of dilated cardiomyopathy
weak and flabby heart, 2 or 3 x bigger, floppy, non specific histological features
what are the causes of dilated cardiomyopathy
genetics (50%- genes that encode heart muscle proteins) toxins (alcoholics- ethanol toxicity), chemotherapy (doxorubicin), cardiac infection, pregnancy
what are the clinical features of dilated cardiomyopathy
heart failure, SOB, poor exercise tolerance, poor ejection
what are the physical characteristics of hypertrophic cardiomyopathy
thickened left ventricle, big strong heart, v heavy, bulging inter ventricular septum. LV luminal reduction,
what are the effects of hypertrophic cardiomyopathy on the circulation
strong contractions, diastolic dysfunction, outflow tract obstruction
what are the histological features of hypertrophic cardiomyopathy
disorganised myofibres, cant contract regularly
what is the extreme effect of hypertrophic cardiomyopathy in athletes
sudden death
what are the causes of hypertrophic cardiomyopathy
genetics (genes that generate cardiac muscle fibres (beta myosin heavy chain)
what are the physical features of restrictive cardiomyopathy
stiff heart (cant relax or expand properly), lack of compliance, diastolic dysfunction, bilateral dilation, cant eject properly, can look normal
why is bilateral dilatation a feature of restrictive cardiomyopathy
a result of back pressure
what are the causes of restrictive cardiomyopathy
deposition of something in myocardium;
- amyloid
- metabolic by-products
- sarcoid
- tumours
- fibrosis following radiation
what is amyloid
abnormal deposition of abnormal protein, forms beta pleated sheets that body cant get rid of
what does amyloid breakdown
breakdown of every vessel and organ
how does amyloid affect the heart
uniformly thick heart, may be localised to the atrium, looks paler
describe the histological features of amyloid
waxy pink material, stains positively for congo red, exhibits apple green birefringence
what are the classifications of amyloid
AA- relates to chronic diseases (rheumatoid), AL- light chains, abnormal immunoglobulin, haemodialysis associated, familial forms, diabetes, alzheimers
what term describe how amyloid affects the body
pansystemic
what type of cardiac disease does amyloid resemble
restrictive cardiomyopathy
what can amyloid
arrhythmogenic death
what is arrhythmogenic right ventricular dysplasia
An inherited myocardial disease associated with paroxysmal ventricular arrhythmias and sudden cardiac death
what inheritance patter does ARVD follow
autosomal dominant
what are the pathological features of amyloid
right ventricle myocardium becomes replaced by adipose tissue
heart big and floppy
what is myocarditis
inflammation of the heart
what are the two forms of myocarditis
infectious (most common) and non infecttious
what can cause an infectious myocarditis
viral (most), bacterial, fungal, protozoal and helminthic
name organisms that can cause myocarditis
coxasckie A and B and ECHO viruses most common
what are the pathological features of infectious myocarditis
thickened ‘beefy’ myocardium
what are the histological features of infectious myocarditis
inflammatory infiltrate
what causes non infectious myocarditis, give 3 examples
immune mediated hypersensitivity reactions;
-hypersensitivity to infection (rheumatic fever after strep throat), to drugs ro SLE (systemic lupus erythematosus)
what are the pathological features of rheumatic fever
thickening and fusion of valve leaflets causing mitral stenosis
short thick chordae tendinae
myocardium patchily inflamed
what are the histological feature of rheumatic fever
aschoff bodies
what is pericarditis
inflammation of pericardial layers
what are the causes of pericarditis
- Infection
- Immune mediated (rheumatic fever)
- Idiopathic
- Uraemic (renal failure)
- Post M.I. (Dressler’s syndrome)
- Connective tissue dse. eg. SLE
what type of infectious pericarditis produces serous effusions
viruses, especially ECHO virus
what type of infectious pericarditis produces purulent effusions
bacterial (pneumonias), fungi (Immunosuppressed pts, post transplant)
what type of infectious pericarditis produces caseous material in sac
tuberculosis
what type of pericarditis does tuberculous pericarditis cause
constrictive pericarditis
what does uraemic pericarditis look like and what causes it
bread and butter, renal failure, accumulation of urea (nitrogen) inflames the pericardium
what is dresslers syndrome
pericarditis post MI (many weeks post)
what causes dressler’s syndrome
immune mediated, damages heart muscle release previously un-encountered material that stimulates an immune response
what are 5 complications of pericarditis
pericardial effusion (inflammation= leajy vessels= fluid), tamponade, constrictive pericarditis (fibrotic healing response= collagen- if cross linked contracts and makes scar around heart compressing it), cardiac failure, death
what is endocarditis
affects heart lining but generally refers to inflammation of the valves
what are the two forms of endocarditis
infectious or non infectious
what can cause infectious endocarditis
very virulent organism, bacteria or fungi- IV drug abuse and septicaemia
when does infectious endocarditis affect the valves
can affect them when normal but usually when abnormal e.g.
- rheumatic heart disease
- prosthetic valves
- congenital defects
- bicuspid valves
- MV prolapse
- calcific disease
what microorganisms cause infectious endocarditis
HACEK haemophilus, actinbacillus, cardiobacteria, eikenella, kignella
PWIDs- candida, staph aureus
prosthetic valves- s. epidermis
what are the vegetations associated with infectious endocarditis
aggregates of organisms on heart valves
how do vegetations cause damage
Bacteria excite acute inflammation and bacterial and inflammatory cell products digest the valve leaflets
Vegetations are also friable and can cause emboli
what are the cardiac complications of infectious endocarditis
Acute valvular incompetence
High output cardiac failure
Abscess, fistula, pericarditis
what other manifestations are common in infectious endocarditis
systemic; clubbing Oslers nodes Janeway lesions Roth spots Splinter haemorrhages Septicaemia Systemic septic emboli – brain, kidney etc. Mycotic aneurysms
what can cause non infectious endocarditis
rheumatic fever, SLE, non infectious thrombotic endocarditis (hypercoaguable states- cancer), carcinoid heart disease
describe non bacterial thrombotic endocarditis
non invasive, doesnt destroy valves, small multiple vegetations
what can NBTE cause
embolic disease
what is NBTE associated with
cancer, hypercoaguable states, mucinous adrenocarinomas
describe the presentation of lupus
Small sterile emboli
Often undersurfaces of the valves or on chords
Range of changes – often small asymptomatic deposits or significant valvulitis
what is LSE
lupus (libman-sacks endocarditis)
what is carcinoid heart disease
carcinoid tumours, common in GI tract and lung, release hormones
carcinoid syndrome occurs when tumour had spread to the liver
what hormones are secreted by the hormone
serotonin, histamine, bradykinin
what do carcinoid heart disease cause (effects and symptoms)
Flushing of skin
Nausea, vomiting and diarrhea
Produces right sided cardiac valve disease
Tricuspid and Pulmonary insufficiency
how common are cardiac tumours and which is the most common
rare, artial myxoma, usually in left atria
what does a artial myxoma lead to
ball/valve obstruction, tumour emboli, maybe endocarditis, systemic fever and malaise
