Arrhythmogenic Right Ventricular Dysplasia / Cardiomyopathy
What is Arrhythmogenic Right Ventricular Dysplasia / Cardiomyopathy?
Also known as ARVD/C, this is an abnormality of the right ventricle of the heart that affects its ability to beat regularly and effectively, thus causing an irregular heartbeat (arrhythmia). This is a genetic, progressive heart condition where the right ventricle is replaced by fat and fibrosis, which causes the arrhythmia.
AVRC affects one in 2500 individuals, though some who have the condition may not develop symptoms. Men and women are equally at risk, with men more likely to show symptoms. And although it is a relatively uncommon cause of sudden cardiac death, it does account for up to a fifth of sudden cardiac deaths in people under 35 years of age.
What causes Arrhythmogenic Right Ventricular Dysplasia / Cardiomyopathy?
ARVD/C is a genetic, heritable condition. Mutations in seven genes have been identified in 40 to 50 percent of individuals with ARVC. There is also some evidence that ARVD/C could result from an infection of the heart muscle.
Patients with ARVD/C are commonly found to have genetic abnormalities in genes that encode for desmosomal proteins. Such mutations mean that the mechanical bonds that hold heart cells together are defective. These cells can pull apart over time, starting a process of scar and fat replacement. This process can be quickened by a high level of exercise, which is why it appears to be common among young athletes.
ARVD/C is inherited in an autosomal dominant manner – an affected individual with a disease-causing mutation has a 50 percent chance of transmitting the mutation to their child. Autosomal recessive inheritance has also been reported in a minority of cases.
Not all individuals who carry an ARVC mutation will have symptoms. Also, not all individuals with ARVC will have a genetic cause of their disease. Environmental factors and physical activity can also influence the disorder.
Why test for Arrhythmogenic Right Ventricular Dysplasia / Cardiomyopathy?
Identifying the genetic cause of your ARVC is important as it can help your physician determine the best way to monitor and treat your condition. It can also help to confirm a clinical diagnosis of ARVC if the diagnosis is unclear. Further, it can help to identify your family members who are at risk of developing the condition, and helps you make informed personal and family health decisions.
How does the test work?
The ARVC genetic test is a blood test ordered by your physician. Your DNA is extracted from the blood and analyzed by searching for mutations that are associated with ARVC. The test takes approximately 10 weeks to complete, and the results will be sent to your physician, who will explain the test results to you.
We will need two tubes of blood (about 7 to 10ml) and a signed consent form from you to send to the laboratory. We recommend genetic counselling before genetic tests are ordered to discuss the implications of the testing and potential results.