Cardiomyopathy Flashcards
Inherited cardiomyopathies tend to be inherited in which pattern?
Autosomal Dominant
What are the two inherited forms of cardiomyopathy?
Hypertrophic obstructive cardiomyopathy
Arrhythmogenic right ventricular dysplasia
How can you prevent sudden cardiac death in primary cardiomyopathies?
implantable cardioverter-defibrillator
What condition is a common cause of sudden death?
Hypertrophic obstructive cardiomyopathy (HOCM)
What causes the pathology in HOCM?
Usually due to a mutation in the gene encoding β-myosin heavy chain protein
HOCM usually causes sudden death in which group?
young athletes
Echo findings in HOCM?
Mitral regurgitation
Systolic Anterior Motion (SAM) of the anterior mitral valve and asymmetric septal hypertrophy
What is the pathophysiology Arrhythmogenic right ventricular dysplasia?
Right ventricular myocardium is replaced by fatty and fibrofatty tissue
Around 50% of patients have a mutation of one of the several genes which encode components of desmosome
What ECG abnormalities would you see in Arrhythmogenic right ventricular dysplasia?
ECG abnormalities in V1-3, typically T wave inversion.
An epsilon wave is found in about 50% of those with ARV - this is best described as a terminal notch in the QRS complex
Can cardiomyopathies be acquired?
yes
What is the mixed category of cardiomyopathies?
patients will have a genetic predisposition to cardiomyopathy which is then triggered by the secondary proces
Name 4 causes of dilated cardiomyopathy?
alcohol
Coxsackie B virus
wet beri beri
doxorubicin
Name 3 causes of Restrictive cardiomyopathy?
amyloidosis
post-radiotherapy
Loeffler’s endocarditis
When does peripartum cardiomyopathy typically develop?
Typical develops between last month of pregnancy and 5 months post-partum
Periartum cardiomyopathy is common in who?
older women
greater parity
multiple gestations
What is Takotsubo cardiomyopathy?
‘Stress’-induced cardiomyopathy e.g. patient just found out family member dies then develops chest pain and features of heart failure
How do you treat Takotsubo cardiomyopathy?
Treatment is supportive
What happens to the myocardium in Takotsubo cardiomyopathy?
Transient, apical ballooning of the myocardium
What are secondary cardiomyopathies?
pathological myocardial involvement as part of a generalized systemic disorder
What are Infective secondary cardiomyopathies typicall caused by?
Coxsackie B virus
Chagas disease
What are Infiltrative secondary cardiomyopathies typicall caused by?
Amyloidosis
What are Storage secondary cardiomyopathies typicall caused by?
Haemochromatosis
What are Toxicity secondary cardiomyopathies typicall caused by?
Doxorubicin
Alcoholic cardiomyopathy
What are Inflammatory (granulomatous) secondary cardiomyopathies typicall caused by?
Sarcoidosis
What are Endocrine secondary cardiomyopathies typicall caused by?
Diabetes mellitus
Thyrotoxicosis
Acromegaly
What are Neuromuscular secondary cardiomyopathies typicall caused by?
Friedreich’s ataxia
Duchenne-Becker muscular dystrophy
Myotonic dystrophy
What are Nutritional deficiencies secondary cardiomyopathies typicall caused by?
Beriberi (thiamine)
What are Autoimmune secondary cardiomyopathies typicall caused by?
Systemic lupus erythematosis
What is the most common form of cardiomyopathy?
Dilated cardiomyopathy (DCM) is the most common form of cardiomyopathy, accounting for 90% of cases.
What is the most common cause of dilated cardiomyopathy?
idiopathic
What are some cardiovascular causes of dilated cardiomyopathy?
myocarditis: e.g. Coxsackie B, HIV, diphtheria, Chagas disease
ischaemic heart disease
hypertension
What drugs can cause dilated cardiomyopathy?
iatrogenic: e.g. doxorubicin
substance abuse: e.g. alcohol, cocaine
What nutrional cause of dilated cardiomyopathy?
thiamine deficiency, wet beriberi
dry is peripheral neuropahty
What role do genetics play indilated cardiomyopathy?
either a familial genetic predisposition to DCM or a specific syndrome e.g. Duchenne muscular dystrophy
What are some infiltrative causes of dilated cardiomyopathy?
haemochromatosis, sarcoidosis
What are the three key points in the pathophysiology of dilated cardiomyopathy?
- dilated heart leading to predominately systolic dysfunction
- all 4 chambers are dilated, but the left ventricle more so than right ventricle
- eccentric hypertrophy (sarcomeres added in series) is seen
What type of murmur would you hear in dilated cardiomyopathy?
systolic murmur
This is because stretching of the valves may result in mitral and tricuspid regurgitation
What would you see on CXR for dilated cardiomyopathy?
‘balloon’ appearance of the heart
Would you hear an S3 in dilated cardiomyopathy?
yes
dilated cardiomyopathy presents with what?
classic findings of heart failure
What would an echo show in dilated cardiomyopathies?
reduction in the LVEF (normal range is 55-70%)
dilated left ventricle and no regional wall motion abnormalities
