BENGALURU: While genetics has been one of the major reasons for sudden cardiac deaths, here is a new electrical test that will allow families around the world, suffering from inherited heart disorders, to discover if they are carrying genetic mutations that cause sudden cardiac arrests.
Such cardiac arrests happen when electrical activity in the heart stops, and the organ can’t pump blood around the body, causing death within 10 minutes. Researchers from Sydney’s Victor Chang Cardiac Research Institute have come up with an electric test that can screen hundreds of gene mutations to pinpoint the exact mutations that are harmful to the heart for those suffering from inherited heart disorder syndromes, that can cause sudden death.
“We need to see if this is practically feasible or not. We should not misunderstand that it will help in all cardiovascular diseases. There are a few genetically driven cardiac diseases like Hypertrophic Cardiomyopathy. In such cases, this test will definitely help,” explains Dr Manjunath C N, Director, Jayadeva Institute of Cardiovascular Research and Hospital.
Lead researcher Professor Jamie Vandenberg, in papers published in the American Journal of Human Genetics, says that sudden cardiac arrests in young people “send alarm bells” for the “high chance” that a genetic condition is to blame.
“The problem with these genetic mutations is that they’re often silent, so the patients themselves don’t know, and it’s only when the first member of the family has a major event that we find out,” Prof Jamie explains. This test assesses variants in an ion channel gene that causes an inherited heart arrhythmia condition called Long QT Syndrome Type 2.
They’re now classifying all known variants in this gene to determine which are benign and which are dangerous, and will be uploading the findings to a giant genetic database that will be accessible to clinicians the world over. The test they have developed can easily be adapted to test other ion channel genes -- not just ones associated with sudden cardiac arrests but a wide range of other diseases spanning neurological, kidney and muscle disorders.
Dr Manjunath added that this will definitely be of help in risk categorising. However, genetic basis alone cannot be a univariate factor for sudden cardiac deaths and that must be remembered, he added.