Genomics in Cardiology

While genetics looks at individual genes, genomics refers to the study of all of a person’s or organism’s DNA and it can provide a more comprehensive view of health and disease. 

Rapid advances in our knowledge and the increased availability and affordability of tests mean that genomics and genetics are increasingly important and relevant within specialist clinics 

Genomic data is increasingly used in the clinic to inform diagnosis, risk stratification, and treatment selection. 

Cardiologists working in specialist inherited cardiac conditions (ICC) teams are taking increasing responsibility for genetic aspects of patient care, including initial counselling and testing, with more targeted support from Clinical Geneticists when needed. 

Other cardiologists, general physicians, and other health professionals in cardiovascular medicine are increasingly likely to encounter genetic and genomic information and should be aware of how to deal with it.   

As well as a role in rarer, inherited cardiac conditions, genomics is increasingly going to have a role in assessment and management of common cardiovascular diseases like hypertension and coronary disease.  

Genomic research directly identifies genes and pathways underpinning disease that may represent new therapeutic targets.  Genetics and genomics also have an important and growing role in patient stratification. 

Take a family history. For example, the evaluation of a patient who’s collapsed might be very different if we know that a family member died suddenly early in life. 

Be aware of when genomics could be relevant and know when and how to refer for specialist advice. All patients with a potentially inherited condition should have the opportunity to be assessed by a specialist Inherited Cardiac Conditions service, and most will be managed in partnership with such a team. 

Be familiar with the genetic test report and with what to do with genetic data in the clinic. For example, will it influence family management, prescribing, etc?  Genetic test results should only be returned to the patient by those confident and competent to do so. 

Families with inherited cardiac conditions 

Patients with a suspected ICC should be referred to a specialist ICC service to ensure they benefit from the latest developments in genomic medicine. 

Most ICCs are autosomal dominant, meaning that immediate family members have a 50% risk of inheriting the same condition. 

Genetic testing can be used to determine the risk to the patient’s family members; this is known as ‘cascade testing’.  

Treatment and management of cardiac conditions 

For some inherited cardiac conditions, treatment can be refined when we understand the precise molecular basis of an individual’s condition. For example, those with inherited arrhythmia may receive treatment tailored to the genetic cause. 

Increasingly other cardiological treatment can also be chosen in accordance with an individual’s genetics. For example, genetic testing can determine whether an individual will be resistant to clopidogrel, or has an elevated risk of developing statin myopathy. 

Genetic information can be used to intervene early. For example, adopting a favourable lifestyle has been shown to reduce coronary disease risk by about 50% even in the presence of a high genetic predisposition.  

New therapies 

Understanding the genetic basis of disease can give us an insight into the molecular mechanisms and pathways involved which can allow us to develop new treatment strategies. For example, specific disease-modifying targeted therapies are currently in phase 3 trials in both dilated and hypertrophic cardiomyopathies. 

Inherited conditions can serve as genetic models for more common forms of disease. For example, PCSK9 inhibitors – a new class of lipid lowering therapy – were developed as a result of studies into familial hypercholesterolemia. 

New genome technologies are also offering the promise of new therapies through gene repair or replacement.