Inherited cardiac conditions are genetic diseases typically passed down within families. Whilst family members are born with the abnormal genes, the conditions themselves can present at any age. Ideally, these conditions should be managed in expert centres with access to specialist input from heart muscle and electrical experts alongside genetic doctors and counselors. This is to ensure both patients and their families get the best possible coordinated care, including genetic testing where appropriate. London Bridge Hospital offers a dedicated Inherited Cardiac Disease Clinic covering all these aspects.
There are many inherited cardiac conditions, however the majority fall into the following broad groups:
Cardiomyopathies: These are genetic diseases affecting the heart muscle and include Hypertrophic Cardiomyopathy (HCM), Dilated Cardiomyopathy (DCM), Arrythmogenic Right Ventricular Cardiomyopathy (ARVC), and Restrictive Cardiomyopathy (RCM)
Inherited arrhythmias (or inherited heart rhythm problems): These are genetic conditions that tend to only affect the electrical circuits in the heart. Common examples include Long QT Syndrome, Brugada Syndrome, and Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT)
Sudden Arrhythmic Death Syndrome (SADS), also known as sudden adult death syndrome: occurs in approximately 30% to 40% of young adults, resulting in sudden death with no obvious causes, due to inherited cardiomyopathies or arrhythmias
Familial Hypercholesterolaemia: Affects around 600,000 people in the UK and can lead to premature strokes and heart attacks
Aortopathies: Refers to inherited problems with the aorta and includes such conditions as Marfan’s Syndrome and Ehlos Danlos Syndrome
Neuromuscular Diseases: Many genetic neuromuscular diseases affect the heart and these include Myotonic Dystrophy, Limb Girdle Muscular Dystrophies and Dystrophinopathies.
Metabolic diseases: This group includes many very rare diseases such as Mitochondrial and storage diseases.
The majority of people that have an inherited cardiac disease of some type is unaware they have it. Most people tend not to have problems or symptoms, but sometimes the first presentation can be with a very severe event. Initial assessment will include drawing a detailed family tree and investigations may include: Electrocardiogram (ECG), Echocardiogram (ECHO), 24 Hour ECG, Exercise stress test, Cardiac MRI or Ajmaline provocation test.
Management involves coordinated treatment of symptoms, assessment of associated risk and preventative measures such as ICD implantation (if the risk is high) and family screening with either investigations (such as ECG and echo) or targeted genetic screening.