Cardiomyopathy Flashcards
what is the commonest cause of sudden cardiac death in young adults?
hypertrophic cardiomyopathy
what is cardiomyopathy?
structural and functional abnormality of the myocardium without coronary artery disease, hypertension, valvular or congenital heart diseases
what are the 4 main types of cardiomyopathy?
- dilated
- hypertrophic
- restricted
- arrhythmogenic right ventricular cardiomyopathy
what is the most common type of cardiomyopathy?
dilated cardiomyopathy
what are the cause of dilated cardiomyopathy?
- ischaemic changes
- hypertensive
- genetic and congenital
- toxin-related (e.g. alcohol abuse, cocaine, chloroquine, clozapine)
- infiltrative (e.g. haemochromatosis, amyloidosis, sarcoidosis)
- peripartum
- thyotoxicosis
- infectious
- stress
- idiopathic
what medications can cause dilated cardiomyopathy?
- anthracyclin chemotherapy (doxorubicin)
- cyclophosphamide
- anti-retroviral drugs (zidovudine)
- chloroquine
- clozapine
what is takotsubo cardiomyopathy?
transient left ventricular ballooning precipitated by intense psychologic stress
stress-induced cardiomyopathy
what are the typical symptoms in dilated cardiomyopathy?
- exertional dyspnoea
- orthopnoea
- paroxysmal nocturnal dyspnoea
- peripheral oedema
- arrhythmia - AF or ventricular tachycardia
- conduction disturbances
- sudden cardiac death
what are the examination findings in dilated cardiomyopathy?
- displaced apex beat
- S3 gallop rhythm (rapid ventricular filling)
- murmur of mitral regurgitation - due to displacement of the valve leaflets
- signs of heart failure - e.g. oedema, hepatomegaly, ascites, raised JVP
what is the diagnostic test for dilated cardiomyopathy?
echocardiogram - may show poor R-wave progression
what is hypertrophic cardiomyopathy (HCM)?
genetic condition characterised by left ventricular hypertrophy of varying degrees
what is the pathophysiology of hypertrophic cardiomyopathy?
mutation in one of several myocyte sarcomere genes such as myosin and troponin, caysing myocyte hypertrophy and disarray
what is the inheritance of hypertrophic cardiomyopathy?
autosomal dominant - though 50% of cases are sporadic mutations
what are the consequences from hypertrophic cardiomyopathy?
- left ventricular outflow tract obstruction (LVOTO)
- disastolic dysfunction
- ischaemia
- mitral regurgitation
what are the typical symptoms of hypertrophic cardiomyopathy?
- presyncope
- syncope
- sudden death
what are the clinical signs of hypertrophic cardiomyopathy?
- ‘jerky’ pulse
- double apex beat
- harsh ejection systolic murmur
- apical thrill
what ECG findings are seen in hypertrophic cardiomyopathy?
- abnormal Q waves
- deeply inverted T waves
- left ventricular hypertrophy
how do you diagnose hypertrophic cardiomyopathy?
echocardiography = left ventricular wall thickness in the absence of any other causes
what is restrictive cardiomyopathy?
involves non-dilated non-hypertrophied ventricles with impaired ventricular filling
what are the broad causes of restrictive cardiomyopathy?
- familial non-infiltrative cardiomyopathy (inherited genetic disorders)
- infiltrative disorders
- storage disorders
- others
how do you diagnose restrictive cardiomyopathy?
- echocardiogram (thickened ventricular walls and valves)
- cardiac MRI - used to distinguish between restrictive cardiomyopathy and constrictive pericarditis
what is the presenting features of hereditary haemochromatosis?
- dilated cardiomyopathy
- diabetes mellitus
- joint pain
- hepatomegaly
- ascites
what is hereditary haemochromatosis?
iron deposition affects the liver, pancreas, joints and heart. it can also affect the skin, pituitary and adrenal glands
what is amyloidosis?
amyloid protein deposition in various tissues in the body, such as kidneys and the heart
