Inherited heart conditions are passed on through families and can prove life-threatening if not detected and treated. Dr Amanda Varnava, a leading cardiologist, explains how common they are and what symptoms they might display.
How common are inherited heart conditions?
Inherited cardiac conditions are actually not uncommon; affecting 1 in 300 of the population. The commonest is familial hyperlipidaemia, which is a family trait of high cholesterol. The next commonest is hypertrophic cardiomyopathy which affects 1 in 500 of the population. The other conditions are rarer and generally affect only 1 in a few thousand of the population.
How serious are they?
Hypertrophic cardiomyopathy is generally associated with relatively few symptoms and a good outlook. However, some patients with this condition may be at risk of sudden death. A careful assessment should be made in all patients with an inherited cardiac condition at their first assessment to look at potential risk. If clear risk features are identified, then patients are offered very effective treatment to protect them from this risk. If no clear risk features are found, then regular reviews are usually recommended. Over time, the risk generally reduces as patients reach older age (over 65 years or so).
What are the symptoms?
Hypertrophic cardiomyopathy can cause symptoms of chest pains, breathlessness and collapse. For other conditions such as ARVC, Brugada syndrome or long QT syndrome, many patients can have little in the way of symptoms, except for collapse which is a red flag for urgent medical assessment.
How are they usually diagnosed?
For some patients, symptoms can trigger a diagnosis. For some, a murmur or an abnormal ECG during a routine medical check-up can lead to a diagnosis in individuals who have no symptoms. However, as an awareness of the familial nature of these diseases increases, for many, the diagnosis follows family screening.
Should everyone be screened for an inherited heart condition?
Screening of the whole population for these conditions is at present not feasible. Targeted screening is recommended for the first degree relatives of patients known to have an inherited cardiac condition. Tragically for some families, screening follows the sudden and unexpected death of a previously fit and well young person.
Screening identifies an inherited cardiac condition in around 40% of these families and offers the opportunity to offer preventative treatment where needed. As there is up to a fourfold greater risk of sudden death from these conditions in competitive athletes; screening of sports people is often performed and is a legal requirement in some countries (such as Italy). In the UK, pre-participation screening is not obligatory, but it is undertaken by an increasing number of sports bodies such as the Football Association.
If you are concerned about your cardiac health, make an appointment with an expert.