Following an application to the Medical Services Advisory Committee (MSAC) by the RCPA, genetic testing for the diagnosis of inheritable cardiac arrhythmia syndromes has been approved for public funding. Although COVID-19 has caused delays to budget cycles, it is hoped that this item will be listed on the Medicare Benefits Schedule (MBS) by late 2021. Honorary RCPA Fellow, Professor Chris Semsarian is an internationally renowned cardiologist and scientist studying genetic heart disease and has been involved in this MSAC application since it began in 2010.

“This is a true “game-changer”. Across the nation we have been struggling to get funding for genetic testing, so this is a massive, massive win for patients. This application involves testing a group of at least 20 genes that are known to be involved in inherited heart rhythm problems. This is something that we just wouldn’t have been able to do ten years ago with the technology available. There has been an explosion in our genetic sequencing technologies, such that we can now test hundreds or thousands of genes very quickly, relatively cheaply to find out the genetic cause of disease.

Associated conditions include long QT syndrome, Brugada syndrome and catecholaminergic polymorphic ventricular tachycardia (CPVT), which may present as palpitations, fainting, cardiac arrest or sudden death. Whilst these disorders are relatively uncommon in the population, they may be found in up to half of all initially unexplained cases of sudden cardiac death in young persons.

“The exciting thing about genetic testing in these conditions is that it impacts on three aspects of care; diagnosis, treatment and prevention. Most importantly, genetic testing allows a diagnosis to be clarified so the cause of disease is established. Depending on which gene is involved, there are also different courses of treatment available. For example, long QT syndrome, which is the more common of the three, has several different subtypes, which may require different medications and prevention strategies,” said Prof Semsarian.

Most arrhythmia syndromes are inherited in an autosomal dominant manner, meaning that first-degree family members such as siblings and children have a 50% chance of inheriting the disease gene abnormality. Cascade testing is therefore offered to family members, where appropriate.

“Cascade testing allows people to make more informed health and family planning decisions. If genetic variants are found in family members, they can be monitored or started on treatment earlier, such as beta blockers, or (in more severe cases) the insertion of a defibrillator, which could save their life. Family members who do not have the genetic variant do not need to be monitored or treated which means this testing is also cost-effective for the health system.

“In addition, people with some gene variants who are planning on having children can potentially consider pre-implantation genetic diagnosis to eliminate the disease gene variant from future offspring,” said Prof Semsarian.

In patients tested for these disease genes where no causative gene variant is identified (so- called “gene elusive” patients), the opportunity arises for research efforts to find novel disease genes.