Presentation: Patient with a family history of cardiomyopathy

A 20-year-old man attends your clinic requesting advice about cardiac screening. His paternal aunt died suddenly at a young age and his father was recently diagnosed with hypertrophic cardiomyopathy following an echocardiogram.

• Cardiomyopathy is usually diagnosed following secondary care investigations. This involves the patient meeting specific diagnostic criteria based on an echocardiogram and an electrocardiogram (ECG).
• Familial cardiomyopathy is suspected when a patient meets the diagnostic criteria on investigation (echocardiogram and ECG with or without an MRI) but non-familial causes are absent. In these cases, the patient may be offered diagnostic genomic testing.
• A pathogenic genetic variant can be identified in 30%–50% of patients with familial cardiomyopathy, and this proportion is increasing as more variants are discovered.
• As inheritance is often autosomal dominant, first-degree relatives are likely to have a 50% chance of carrying the same variant.
• In rare circumstances, there may be a different mode of inheritance or the cardiomyopathy may be part of a recognised condition, such as Fabry disease, amyloidosis or Noonan syndrome.

• It is important to take a careful family history that includes any sudden deaths in the family.
• Patients should be offered referral to a clinical genetics service if they have an affected first-degree relative with an identified pathogenic variant.
• In cases in which no pathogenic variant has been identified but familial cardiomyopathy is suspected, first-degree relatives of affected patients should be referred to cardiology services for screening, including an ECG and an echocardiogram.
• Due to varying degrees of penetrance, signs of cardiomyopathy may be absent on initial screening but develop later in life. Because of this, screening is often offered on an ongoing basis.
• The consensus view of the European Society of Cardiology (see the resources list below) is that children should be referred to paediatric cardiology for clinical screening from around the age of 10, or earlier if there is a family history of childhood-onset cardiomyopathy. The age of predictive genomic testing is usually guided by the clinical genetics team.
• For information about how to arrange testing in Wales, Scotland or Northern Ireland, see our dedicated Knowledge Hub resource.
• Information about patient eligibility and test indications were correct at the time of writing. When requesting a test, please refer to the National Genomic Test Directory to confirm the right test for your patient.

For clinicians

• European Society of Cardiology: Hypertrophic cardiomyopathy guidelines
• Patient Info: Cardiomyopathies

For patients

• British Heart Foundation: Cardiomyopathy
• British Heart Foundation: Life with hypertrophic cardiomyopathy (downloadable booklet)