Dr Mark Ryan presented an update on cardiomyopathies at the October medical update.
Types of cardiomyopathies include:
- Hypertrophic cardiomyopathy (HCM) is one of the most common causes of sudden death in young people during sport. It is found in up to 1 in 200 people. Sometimes it causes no symptoms, or it can lead to blackouts and sudden death. It is usually an unexpected diagnosis, with abnormal q waves, LVH and bundle branch blocks on ECG, then confirming the diagnosis on echocardiogram. The ejection fraction is normal or hyperdynamic (better than normal). Risk stratification is important, which includes looking for major and minor risk factors and using online calculators.
- Arrhythmogenic RV Cardiomyopathy has deep T wave inversions V1-3 and epsilon waves on the ECG.
- Restrictive cardiomyopathy can be caused by amyloid, sarcoid and a long list of other causes.
Cardiomyopathy can be congenital, but may present differently in individuals within a family. If you do find someone with a cardiomyopathy, take a careful history looking for other affected family members. There are many genes involved. Some mutations don’t get expressed until later in life (i.e. aged 30-40+), so even if a patient with a family history is normal at age 25, they may still need specialist follow up.
Causes of sudden cardiac death include structural and arrhythmogenic causes. HCM is one of the most common structural causes. Long QT and Brugada are some of the arrhythmogenic causes.