Understanding the genetic risk factors of hereditary heart arrhythmias.

In light of recent news about Tess Hughes, a young woman who tragically lost her life due to a genetic condition known as arrhythmogenic right ventricular cardiomyopathy (ARVC), we want to address concerns and provide information about this condition.

If you or someone you know is worried about genetic risks that can increase one's chances of developing a heart arrhythmia or increasing the risk of sudden cardiac death, we hope this blog post will help alleviate some of your concerns and guide you on a path towards proactive health management. 

Understanding ARVC: Causes, Symptoms, and Prevalence

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic heart muscle disorder that affects the ventricles, the lower chambers of the heart. ARVC occurs due to a gradual weakening of the ventricle wall, potentially leading to life-threatening abnormal heart rhythms (cardiac arrhythmias), especially during intense physical activity symptoms of ARVC. Symptoms usually begin in adulthood.

It is estimated that ARVC affects between 1 in 1,000 to 1 in 2,500 people¹. However, ARVC may be more common than reported, as it can be challenging to detect in people with mild or no symptoms.

In Tess Hughes' case, the condition went undetected until her sudden and tragic passing in her sleep. This scenario highlights the importance of raising awareness about heart arrhythmias and the benefits of early detection to prevent further loss of lives.

Taking Action: Genetic Testing and Monitoring

One of the key takeaways from Tess's story is the power of genetic testing and monitoring for individuals who may carry the ARVC gene. The field of cardiac genetics is evolving rapidly. It is reported that variations in at least 13 genes can lead to ARVC. However, only 60% of people with ARVC will have an identifiable genetic cause. The most common genetic cause is a variation in the PKP2 gene inherited in an autosomal dominant pattern. This means that once a person is identified as carrying a variation in this gene, there is a 50% chance that any of their first-degree relatives will also carry the variation. As in Tess’ family’s story, not all carriers will experience symptoms - however, knowing if you are at increased risk of an arrhythmogenic disorder could save your life as you can access screening, surveillance and potential interventions to decrease the chances of sudden death.

Once Tess's mother, Karen Hughes, became aware that ARVC was passed through her side of the family, she underwent genetic testing, which confirmed that she carries a genetic predisposition to the condition and was diagnosed with the disorder, enabling her to have an internal defibrillator implanted proactively. Additionally, many of Tess's relatives and siblings were found to carry the ARVC gene and are now being regularly monitored. This proactive approach - will undoubtedly improve the heart health outcomes for members of Tess’ family.

It is crucial for individuals with a family history of ARVC to consult with medical professionals specialising in cardiac genetics. By understanding your risk and having a clinical assessment, picking up early signs of heart damage may be possible. If a gene variant is known in the family, is it possible for blood relatives - especially first-degree relatives (parents, siblings and children) to consider whether genetic testing is appropriate?

You can control your family's narrative by taking proactive steps to manage the condition and minimise potential catastrophic events. Using IVF technologies can also use this information to prevent passing it on to future generations. 

Genetic Testing and Counselling for ARVC

Seeing the support and resources available to families affected by ARVC is heartening in the face of tragedy. The Victorian Institute of Forensic Medicine, through its Family Health Information Service, offers valuable support to grieving families, information, and referrals to medical specialists. They aim to diagnose previously undetected conditions and provide support to families grappling with concealed medical conditions.

Furthermore, the Royal Melbourne Hospital's cardiac genetics clinic investigates family histories and provides long-term care for individuals referred to their services. Individuals and families affected by ARVC can receive the necessary guidance and care by working closely with healthcare professionals and utilising available resources.

Those who may not get access to testing through these options can access testing privately. At Eugene, we offer comprehensive genetic testing services for cardiac conditions, including some genetic causes of ARVC.

Our genetic tests can help identify specific genetic variants with a well-documented association with the condition, providing valuable insights into your cardiac health. Just to let you know, Eugene does not offer diagnostic testing, and there are limitations to the proactive test.

Eugene’s Proactive Heart Health testis most appropriate for healthy individuals looking to learn more about their inherited risk of a cardiac condition. It is not designed for people with symptoms. Those who have symptoms should consider diagnostic testing with their cardiac specialist.

Furthermore, we understand that genetic testing can be an emotionally charged process. That's why we offer genetic counselling services to support you throughout your testing journey. Our certified genetic counsellors will interpret your test results, address any concerns you may have, and guide you in making informed decisions about your healthcare.

Managing ARVC and Leading a Healthy Life

Living with ARVC requires a comprehensive approach to managing the condition effectively and reducing the complication risk. Upon diagnosis, your healthcare provider will create a personalised management plan tailored to your needs. Here are some aspects of managing ARVC:

• Routine cardiac evaluations, such as electrocardiograms (ECGs) and echocardiograms, can help monitor the structure and function of your heart.

• Depending on the severity of your condition, your healthcare provider may prescribe medications to manage specific symptoms and reduce the risk of arrhythmias. In some cases, implantable cardiac devices, such as defibrillators.

• Genetic counselling plays a vital role in understanding the hereditary aspect of ARVC and its potential impact on family members. A genetic counsellor can guide genetic testing, assess the risk of passing on the condition, and help you make informed decisions about family planning.

Family Screening

• When considering genetic testing for heritable heart conditions, involving your family in the screening process is important. Genetic counsellors can guide your family members, giving them the necessary information to make informed decisions about their cardiac health.

Conclusion

It is crucial not to let fear or uncertainty overshadow your well-being. If you have concerns about genetic causes of heart disease, please take proactive steps to seek medical advice and take the appropriate assessment. Early detection and personalised management and support can significantly improve your long-term outcomes.

Remember, you are not alone on this journey. Contact healthcare professionals, genetic counsellors, and support networks to receive your needed guidance and support. By taking control of your health and staying informed, you can lead a fulfilling life while managing ARVC effectively.

¹Wallace R, Calkins H. Risk stratification in arrhythmogenic right ventricular cardiomyopathy. Arrhythm Electrophysiol Rev. 2021;10:26–32.

Disclaimer: The information provided in this blog post is for educational purposes only and should not be considered a substitute for professional medical advice. Always consult your healthcare provider for personalised guidance and treatment recommendations based on your circumstances.