Cardiomyopathies Flashcards
What are 2 genetic cardiomyopathies?
- Hypertrophic obstructive cardiomyopathy
- Arrhythmogenic right ventricular dysplasia
What is hypertrophic obstructive cardiomyopathy?
- Leading cause of sudden cardiac death in young athletes
- Usually due to a mutation in the gene encoding β-myosin heavy chain protein
- Common cause of sudden death
- Echo findings include:
- MR
- systolic anterior motion (SAM) of the anterior mitral valve
- asymmetric septal hypertrophy
What is 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
- 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
Name mixed cardiomyopathies?
- Dilated cardiomyopathy:
- A dilated, flabby heart of unknown cause
- Restrictive cardiomyopathy
What is the cause of dilated cardiomyopathy?
Classic causes include:
- Alcohol
- Coxsackie B virus
- wet beri beri (thiamine deficiency)
- doxorubicin
- ↑bp
- haemochromatosis
- autoimmune
- peri- or postpartum
- thyrotoxicosis
- congenital (x-linked)
What are the presentation and signs of dilated cardiomyopathy?
Presentation:
- Overall: fatigue, dyspnoea, pulmonary oedema
- Cardiac: RVF, Emboli, AF, VT
Signs:
- Overloaded: ↑Pulse, ↓bp, ↑jvp, oedema, pleural effusion
- Rhythm + cardiac: Displaced diffuse apex, S3 gallop, Mitral or tricuspid regurgitation (mr/tr)
- Abdominal: Jaundice, hepatomegaly, ascites
What tests do you order for dilated cardiomyopathy?
Blood:
- plasma bnp
- ↓Na+ indicates a poor prognosis
CXR:
- cardiomegaly (baloon appearance)
- pulmonary oedema
ECG:
- tachycardia
- non-specific t wave changes
- poor r wave progression
ECHO:
- globally dilated hypokinetic heart
- low ejection fraction
- Look for mr, tr, lv mural thrombus
What is the treatment for dilated cardiomyopathy?
- Bed rest
- Diuretics
- Digoxin
- ACE-i
- Anticoagulation
- Biventricular pacing
- ICDS
- Cardiac transplantation.
What are the causes of restrictive myopathy?
- Idiopathic
- Amyloidosis
- Haemochromatosis
- Sarcoidosis
- Scleroderma
- Löffler’s eosinophilic endocarditis
- Endomyocardial fibrosis.
What is the presentation of restrictive cardiomyopathy?
- Features of rvf predominate:
- Overload: ↑jvp with prominent x and y descents, oedema
- Abdomen: hepatomegaly; ascites
How do you diagnose and treat restrictive cardiomyopathy?
Cardiac catheterization + treat the cause
What are examples of acquired cardiomyopathy?
- Peripartum cardiomyopathy
- Takotsubo cardiomyopathy
What is peripartum cardiomyopathy?
- Typical develops between last month of pregnancy and 5 months post-partum
- More common in older women, greater parity and 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
- Transient, apical ballooning of the myocardium
- Treatment is supportive
What are secondary cardiomyopathies?
