A family-based approach to inherited arrhythmia
"It runs in the family"
That’s a statement doctors are listening for when they ask their patients about cancer, heart disease, diabetes and many other conditions. Because a wide range of diseases show up again and again in families, generation to generation, family histories are critical for doctors making accurate diagnoses and determining effective treatments.
Given the significance of family histories, Dominic Abrams, MD, of the Cardiology Department at Boston Children’s Hospital, is developing a new approach to treating inherited diseases, an approach that looks at the entire family rather than just the single patient.
A major feature of many inherited heart conditions is arrhythmia, which is a disturbance in heart rhythm. This condition includes the arrhythmic syndromes, such as long QT syndrome (LQTS), Brugada syndrome (BS) and catecholaminergic polymorphic ventricular tachycardia (CPVT), where rhythm disturbances are the only feature. The condition also includes cardiomyopathies, such as arrhythmogneic right ventricular cardiomyopathy and hypertrophic cardiomyopathy, where arrhythmia is associated with heart muscle conditions. The arrhythmia associated with these conditions can lead to palpitations, syncope (black-outs) and sudden cardiac death, often in response to specific triggers.
According to Abrams, arrhythmias show “dominant inheritance.” “People who have a first-degree relative with one of these conditions, typically have a 50% chance of also having the condition,” he says. Moreover, “most of these conditions can affect individuals from the womb into your 80s, meaning assessment of the whole family, irrespective of age, is of great importance.”
Through the new program called “Inherited Cardiac Arrhythmia Program” Abrams and his colleagues are helping to develop more familial-based services for inherited arrhythmia. The program centers on meetings with entire families that take place all at once, usually in one day. This approach, Abrams explains, creates a “one-stop shop where we can diagnose problems and come up with a plan.”
Diagnosing inherited cardiac conditions is “often a detective game,” Abrams states. “We know that some family members, especially children, may show no or only very subtle evidence of the disease, making accurate clinical diagnosis challenging.” Genetic testing, he says, is an increasingly useful mechanism to identify all family members at risk of developing the condition, although the results require detailed evaluation and correlation with clinical findings.
When doing this “detective” work, Abrams and his team start by looking at first-degree relatives. For example, if one family member is diagnosed with a condition, shows symptoms or suddenly dies from a known or suspected arrhythmia, “we get as much information as we can ahead of time—autopsy results, results of an EKG performed for another reason—so when the family walks through the door, we have a targeted and family-specific approach to the next wave of investigations.” Complete medical information is gathered, and genetic testing results, if available, are used to reveal an inherited heart condition.
During the day-long meetings, children are typically seen in the morning and undergo specific investigations, while parents and other adult family members are seen in the afternoon. At the end of the day, findings are explained to the entire family, and a plan for further tests or treatment is presented. Not only does this strategy make clinical sense by allowing for more comprehensive interpretation of clinical and genetic data, but, as Abrams explains, it also allows for exciting research opportunities. “Occasionally, findings in one family shed new light on our understanding of the genetic basis of one specific condition and have significant implications for other patients.”
This all-day, all-inclusive approach was designed, Abrams says, “to make sure the whole family is looked after and is getting a consistent and clear message, avoiding the problem of having the family spread over different centers and allowing us to identify similarities and variability between individuals.”
Ultimately, Abrams and his colleagues are seeking to create the family-centered, coordinated approach fundamental to the investigation and care of families with inherited cardiac conditions.
The Inherited Cardiac Arrhythmia Program is evolving rapidly, and Abrams and his team at Boston Children’s are working in close collaboration with colleagues at neighboring affiliated hospitals.