Paediatric Cardiology 2 Flashcards
What do the genes often involved in hypertrophic cardiomyopathy encode?
Mutations of the genes encoding cardiac β-myosin heavy-chain (MYH7) and myosin-binding protein C (MYBPC3)
Approximate prevalence of dilated cardiomyopathy:
50/100,000 = 1/2000
How is hypertrophic cardiomyopathy inherited?
Autosomal dominant
What cardiac issue is associated with Duchenne and Becker Muscular Dystrophy?
Dilated Cardiomyopathy
What % of dilated cardiomyopathy is genetic?
20-50%
Describe presentation of dilated cardiomyopathy (common and uncommon features)
- often presents in congestive heart failure (rarer: palpitations, syncope or sudden death)
- cough, dyspnoea and wheeze on exertion
- abdominal pain, nausea
- irritable/lethargic
- may have creps/wheeze on examination
- hepatomegaly
- increased precordial impulse
- increased cardiac size
- tachycardia, gallop rhythm (kentucky, S3), MV insufficiency
- narrow pulse pressure
- uncommon: pallor, hypotension, altered mentation, shock
- also may have signs of underlying issue (e.g. Gower sign for DMD)
ECG signs of dilated cardiomyopathy
Non-specific: atrial/ventricular hypertrophy, T-wave anomalies, atrial/ventricular arrhythmias
Commonest cause of dilated cardiomyopathy?
Idiopathic
Which chemotherapy agent is most likely to cause cardiomyopathy? (Bonus: what additional treatment makes it worse?)
Doxorubicin
Radiotherapy concurrently makes it worse
What metabolic issues are associated with dilated cardiomyopathy?
- Mitochondrial myopathies e.g muscular dystrophies
- Disorders of fatty acid oxidation.
- Phospholipid disorders
What is the commonest cause for cardiac transplantation?
Dilated cardiomyopathy
Risk factors at DCM diagnosis for subsequent death or transplantation:
- Older
- congestive heart failure
- low left ventricular fractional shortening z score
- underlying etiology
Which syndrome is associated with hypertrophic cardiomyopathy?
Noonan
Describe the characteristic ECG in Pompe disease:
Prominent P waves, a short P-R interval, and massive QRS voltages
What is the cardiac issue associated with mumps?
Endocardial fibroelastosis (EFE)
What viruses can cause myocarditis?
Most common:
- Coxsackievirus and other enteroviruses, CMV, Hep C
- Adenovirus
- Parvovirus, parechovirus
- Influenza
- EBV, Enteroviruses
(Hep C - mainly in Asia)
Describe the variety of signs/symptoms of myocarditis.
Infants and young children specifically - fulminant presentation with fever, respiratory distress, tachycardia, hypotension, gallop rhythm, murmur.
Can also have rash, end organ involvement such as hepatitis or aseptic meningitis.
Generally: chest discomfort, fever, palpitations, easy fatigability, or syncope/near syncope. Cardiac findings include overactive precordial impulse, gallop rhythm, apical systolic murmur of mitral insufficiency. In patients with associated pericardial disease, a rub may be noted. If cardiac failure: hepatic enlargement, peripheral oedema, and creps/wheeze
Describe the possible ECG changes in myocarditis.
Nonspecific
- sinus tachycardia
- atrial or ventricular arrhythmia
- heart block
- decreased QRS voltages
- nonspecific ST and T-wave changes, often suggestive of acute ischemia
What is the mortality of acute myocarditis in newborns?
Up to 75%
What % of patients with myocarditis are reported to recover LV function?
10-50%