Addressing Cardiovascular Genetic Testing in Children

According to a new statement from the American Heart Association, cardiovascular genetic testing in children presents challenges that require pre-and post-test counseling with a personalized approach for families.

This is the first American Heart Association scientific statement guiding genetic testing of cardiovascular disease in children. Previous statements issued by the Association regarding genetic testing primarily focused on adults.

According to the statement writing group, it was important to issue a pediatric-focused statement recognizing the unique challenges children and their families face with pediatric gene testing.

“There is growing recognition that a genetic test is not a simple blood test where you get a yes or no answer. With this statement, we illustrate some of that complexity, particularly as it relates to cardiovascular diseases passed from parents to children,” chair of the statement writing group Andrew P. Landstrom, MD, PhD, FAHA, said in a press release.

“We provide consensus-based recommendations for best practices and principles to assist health care professionals in determining when cardiovascular gene testing is appropriate in children, highlighting the need for a multi-disciplinary approach to family counseling before and after testing, and we raise the importance of appropriate follow-up.”

The statement writing group explained that pre-test counseling is critical in the genetic testing of children. Before deciding on the genetic test, children and their parents should go through counseling. The counseling will cover the potential benefits of the test as well as the disadvantages.

Pre-test counseling should address the possibility that the genetic results may be inconclusive since there is still much to discover regarding genetic components of several diseases of the heart. Clinicians must work with families to prepare them for all potential scenarios before the test is conducted.

Additionally, pre-test counseling allows the families to address any concerns about possible medical costs or the possibility that genetic test results could lead to discrimination or an inability to obtain health insurance in the future. The statement outlines federal laws families should know to help to alleviate some of these concerns.

According to the statement, post-test counseling and follow-ups are also essential. After the genetic test results are in, post-test counseling allows clinicians to explain the findings and how the information will be used to develop a treatment plan. Follow-ups should be ongoing as medical professionals continue to learn more about genetics and the field of study evolves.

Landstrom explained that it’s important to explain to families what’s ahead before they begin the process. In diseases such as QT syndrome or catecholaminergic polymorphic ventricular tachycardia, genetic testing can identify possible causes of the disease 60 percent -75 percent of the time.

If medical professionals suspect that an individual has one of these diseases, the test will most likely find the gene variant responsible for the disease about two-thirds of the time.

“Identification of the presence or absence of this gene variant in family members of the individual can identify those who are, or are not, at risk of developing the same disease. In this situation, gene testing makes sense in most scenarios,” Landstrom said.

“With some inherited cardiovascular diseases, the genetic causes are not well known and the likelihood of finding the gene causing the condition is much lower in pediatric testing. For these diseases, the likelihood of finding one of these genetic variants of uncertain significance can make the test challenging to interpret. These are important considerations for clinicians and families to understand and discuss together before testing is done.”

There are two main types of cardiovascular genetic tests provided to children; diagnostic and risk-predicting. If a child is showing signs of a hereditary heart condition after a cardiology workup, a diagnostic genetic test may be requested to determine if the child has the gene variants associated with the condition. A diagnostic gene test can refine the diagnosis and assist with treatment decisions.

A risk-predictive test typically occurs when a close relative is found to have a genetic variant associated with a heart condition.

“If a relative is found to have the same gene variant that was determined to be the likely cause of disease in an affected family member, the relative may be at-risk for developing the same condition. This doesn’t mean they are guaranteed to develop the condition in the same way, or even that they will get the condition at all, just that they are ‘at-risk,’ and they will need to be closely monitored because of this increased risk,” Landstrom said.

“Conversely, if the gene variant causing the condition in the family is identified and a relative tested doesn’t have that genetic variant, that person likely does not need additional follow-up or screening beyond that of the general population.”

The statement recommends that before conducting genetic testing, practitioners should consider referring children with suspected heritable cardiovascular disease to a multidisciplinary cardiovascular genetics program. While these programs are typically at large medical centers, improved telehealth has made them more accessible.

“Pediatric genetic testing has important considerations beyond those of adult testing, including the vulnerability of children as a population, and these considerations should be at the forefront of all decision-making about genetic testing,” Landstrom said.

“Additional factors to help inform the decision-making process to ensure the best outcomes for children and family members are the characteristics of the specific heritable cardiovascular disease, the likelihood and timing of disease development, the availability of therapies and interventions that can treat or prevent disease, and the availability and cost of testing.”