Cardiomyopathy and myocarditis Flashcards
What is dilated cardiomyopathy?
- dilation of the ventricles and thinner ventricular walls, hence affecting ventricular function
- strength of muscle contraction will be weaker
- can be primary/end result of any pathological insult to the myocardium
Causes of dilated myopathy
- Genetic and familial: SCN5A gene, muscular dystrophy
- inflammatory: viruses, autoimmune, postpartum
- toxic; drugs, exogenous chemicals, alcohol, endocrine
- Injury, cell loss, scar replacement
- Ischaemia/valvular causes
Irreversible/reversible causes of dilated cardiomyopathy
-alcohol
-endocrine
-tropical disease
-post partum
-haemaochrmatosis ( ion storage disease)
sarcoid
Symptoms of dilated cardiomyopathy
Slow onset
- dyspnoea
- fatigue
- orthopneoa
- PND
- ankle oedema
- weight gain of fluid overload
- cough
PMX of dilated cardiomyopathy
- systemic illness
- travel
- vascular disease
- thyroid, neuromuuscular disease
Examination of cardiomyopathy (findings)
-poor superficial perfusion
-thready pulse
0irregular in AF
-sob at rest
-narrow pulse pressure
-high JVP
-may have TR waves?
-displaced apex
-S3, S4
-MR murmur
=pumnary oedema, PE, ankle oedema, sacral odema, acites, hepatomegaly
Investigation of dilated cardiomyopathy
- ECG
- CXR
- N termial prp BNP?
- Bloods ( FBC, U+E)
- ECHO
- CMRI
- Coronary angiogram
- Biopsy
Treatment -Non specific
Correct:
- anaemia
- exacerbating drugs ( NSAIDS)
- endocrine disturbance
- reduce fluid/salt intake
- manage weight
- reduce alcohol intake
Treatment - Specific
- ACEI
- ATII blockers
- diuretics
- beta blockers
- spironlactone
- anticoagulants
- cardiac transplant
- SCD risk assestment with ICD/CRT-DP implant ( pacing systems)?
What is restrictive and infiltrative cardiomyopathy?
- when ventricle has reduced compliance so cannot fill well.
- stiffness
Causes of restrictive and infiltrative cardiomyopathy
-Non infiltrative: familial, forms of HCM, scleroderma, diabetic, pseudoxanthoma elasticum
Infiltrative; amyloid, sarcoid
Storage disease; haemachromatosis, fabry disease
Endomyocardial; fibrosis, carcinoid, radiation, drug effects
Evalutation of restrictive and infiltrative cardiomyopathy
- ECG
- CXR
- N termial prp BNP?
- Bloods ( FBC, U+E ; look out for sarcoid + haemachromatosis)
- autoantivoies for sclerotic CT diseases
- amyloid requires non cardiac biopsy to establish diagnosis
- fabry; low plasma alpha galactosidase A activity
- ECHO
- CMRI
- Coronary angiogram
- Biopsy (more helpful but high false negative rate)
Treatment - Specific for restrictive infiltrative cardiomyopathy
- limited diuretics as low filling pressures cause problems
- beta blockers limited
- anticoagulants
- cardiac transplant
- SCD risk assestment with ICD/CRT-D/P implant ( pacing systems)?
- if Fe overload, specific forms of amyloid of fabrys then specific treatment are available
- endomyocardial fibrosis has little specific
Prognosis of restrictive and infiltrative cardiomyopathy
-if irreversivle poor prognosis
What is hypetrophic cardiomyopathy
-part of heart becomes thickened idiopathic. This results in heart being less able to pump properly
Causes of hypertrophic cardiomyopathy
Genetics
-sacromere gene defect which is autosomal dominant.
Describe the pathology of Hypertrophy cardiommyopathy
- myocyte hypertrophy and disarray
- segmental wall thickness >14mm or >12mm in primary relative
- can be apical, septal or generalised
- impaired relaxation so behaves in a restrictive manner
- if septal hypertrophy this can with mitral valve defect lead to LVOT obstruction
- CA also affected with small vessel narrowing and consequent ischaemia and fibrosis, arrythmias are common
Symptoms of hypertrophic cardiomyopathy
- asymptomatic
- fatigue
- dyspnoea
- angina
- chest pain (exertional)
- syncope related to arrhythmias
Examination of hypertrophic cardiomyopathy
- none
- notched pulse pattern
- irregular pulse if in AF or ectopy
- double impulse over apex, thrills and murmurs, often dynamic, LVOT murmur will will increase with valsalve and decrease with squatting
- JVP can be raised in very restrictive filling
Symptoms of hypertrophic cardiomyopathy
- breathlessness
- palpitations
- syncope
- exertional symptoms
- SCD
- asymptomatic
- fatigue, anginal chest pain, exertional pre syncope
Examination findings of hypertrophic cardiomyopathy
- none
- notched pulse pattern/irregular
- double impulse over apex, thrills, murmurs, dynamic, LVOT murmur will increase with valsalve and decrease with squatting
- JVP can be raised in a restrictive filling
Investigation of hypertrophic cardiomyopathy
- ECG ( abnormal but few normal where phenotype is poorly expressed in genotype +ve individuals)
- Echo
- CMRI
- risk for SCD, may need ICD
Non specific treatment for hypertrophic cardiomyopathy
- avoid heavy excercise/dehydration
- consider genetic testing
- regular FU to re appraise risks and progress
Specific treatmet for hypertrophic caridomyopathy
- drugs to try and enhance relaxation
- beta blockers, verapamil, disopyrimide
- if AF anricoagulate
- surgical/alcohol septal ablation
- ICD if required based on risk stratification
