According to the March of Dimes, 40,000 children are born with heart defects each year in the United States. That’s nearly 800 kids every week. In about 20% of the cases, (8,000 annually), family history plays a significant role. The remaining 80% are due to other causes we may not typically consider.
Heart defects come in several forms, both structural & electrical. Structural defects arise from abnormal formation of the heart or major blood vessels and can be due to a genetic or developed condition. There are at least 18 distinct types of heart defects with many additional anatomic variations.
Electrical defects can cause the heart to beat irregularly or rapidly, and can even cause it to stop beating altogether. Underlying and undetected genetic or congenital cardiovascular diseases that occur in youth is a rising concern with parents as more reports of athletes collapsing on the playing field from Sudden Cardiac Arrest (SCA) find their way through the media.
SCA in youth is a horrific, complex event. The reliable identification of individuals at risk has become a focus of many for several reasons, including the opportunity to try to reduce the number of these events.
There has been much discussion in recent years over the incidence of heart-related issues in youth. Much of the controversy is due to several differing reports on cardiovascular screening usefulness. Unfortunately, there is no US centralized or mandatory registry for pediatric sudden cardiac arrest (SCA). Available data is generally collected through media reports, lay SCA advocacy groups, or from peer-reviewed publications, often derived from major referral medical centers. Some say the number is somewhere around 100 deaths per year. However, in 2008 The Center for Disease Control published estimates with the number of deaths closer to 2,000 a year (<18 yo). In 2014, the American Heart Association (AHA) released the Heart Disease and Stroke Statistics – 2014 Update, published in Circulation, that estimated the number of deaths to be 7,000, (<18 yo) based largely on information derived from an ongoing registry from the Resuscitation Outcomes Consortium (ROC) multi-center clinical trial. With such disparity in the statistics, it’s no wonder we haven’t made it a priority to find the most reliable way to identify these kids sooner.
Many of the heart screening programs in the US, understandably, target athletes. Most of these programs are born out of the loss of a child and operate with the assistance of an adult cardiologists or family physician. Typically these screenings include Electrocardiogram’s (ECG) only. ECG has been the tool of preference due to the low per-test cost, capability of identifying certain heart disorder’s, and ease to perform. They are often made accessible through community-based events because the idea of getting every child screened seems to make sense. The quality of these screenings, however, is very difficult to manage due to the often large number of kids to be screened in a small amount of time. The process is further complicated by the lack of consistent technicians conducting the screenings as well as the ability for the volunteer cardiologists to provide accurate interpretations of so many ECGs in a limited amount of time. It could be argued that a more controlled setting, without the pressure of trying to help an unlimited number of kids in a set time period, would help improve the quality of screenings being offered.
The ECG is subject to issues related to consistency, reproducibility, and variability in interpretation. The performance of the ECG, in a real-world mass screening setting, will vary due to readers and technicians with vastly different expertise and efficiency being confronted with large numbers of studies to perform and interpret rapidly. There have been efforts to improve test specificity and recognition of abnormalities. These initiatives, which attempt to reduce high false-positive rates, have stated success in improving normal from abnormal ECGs by reducing false-positives to a range of <5% to 10%. However, there is concern that attempts in improving the test outcomes may result in higher false-negative results, which in fact represent athletes with potentially lethal cardiovascular diseases that the screening is designed to recognize and protect.
Additionally, difficulties in test interpretation can be expected in mass screening if the 12-lead ECG is used to detect (or raise suspicion) of those diseases that cause SCA in young people and athletes. ECGs can also miss dangerous heart problems. For those with hypertrophic cardiomyopathy (HCM), a thickening of the heart muscle, and the most common cause of sudden cardiac death in young athletes, research shows that at least one in 10 will have a normal ECG. Coronary artery anomalies are the second-most common cause of death in youth and are missed at least nine out of 10 times through ECG alone.
So where do we go from here? Most reports on cardiovascular screening efficacy have predominantly involved populations of adolescents and young adults (school-aged, 12–25 years old, of both sexes) participating in competitive athletics. It has long been assumed that strenuous physical activity exacerbates abnormalities. Therefore, the true effect of SCA in the adolescent/young adult population may truly be underestimated when you include athletes and non-athletes alike. There are also studies suggesting that a significant percentage of the childhood population has cardiac disease undetected by clinical means alone. Some of these children require corrective intervention procedures, and/or follow-up by a pediatric cardiologist. The challenge is to develop a strategy to detect these children because careful physical examination, performed by a medical professional, may not be adequate.
The America Heart Association (AHA) and American College of Cardiology (ACC) recommends a careful evaluation with personal and family history and a cardiovascular examination be done on young people, athletes and non-athletes alike. But there are issues with the recommendation, however, that only 5% of the examiners use the 14-point questionnaire, or they lack the expertise to diagnose heart issues in children through physical exams. The AHA/ACC also recommends that if there is any initiative to screen youth for heart abnormalities, it be conducted properly, and with adequate trained resources. One could assume since the target age of the group is school aged kids, a pediatric cardiologist should lead the effort.
Not to take anything away from ECG testing, because it is a useful test and is fairly inexpensive, typically a $25 screening test, but it’s really only effective at diagnosing 3 potentially fatal heart abnormalities. The ability to fully screen the population in question is achievable, but must include additional testing that includes echocardiograms or echo, (heart ultrasound). Not only are echo’s more accurate in diagnosing HCM, it is the gold standard and the next in line of tests when HCM is indicated on ECG. Being able to “peer into the heart” allows for more accurate diagnosis of structural abnormalities thus increasing the overall accuracy of heart screenings.
And there are a number of reasons to justify early diagnosis of cardiac abnormalities. First, repair of congenital abnormalities, such as septal defects (an estimated 25% of the population), reduces the later risk of arrhythmias, right ventricular dysfunction, and pulmonary hypertension. Second, not only severe but also some mild cardiac abnormalities, have potential long-term health consequences and risk of bacterial endocarditis. Additionally, echo is the only way to diagnose a dilated aortic root, an indicator of potential connective tissue disorders (Marfan’s).
Most parents assume when they sign their child up for a heart screening the entire heart is being evaluated, including heart walls, coronary arteries, valves, etc. for underlying and undetected genetic and congenital cardiovascular diseases. Parents and kids deserve the highest quality heart screening available so they can take corrective action if necessary. Any screening effort should include Blood Pressure readings, ECG tracing, and an Echocardiogram (all for under $150) to give the best opportunity to diagnose structural and electrical issues. After all, would you buy your child a $25 pair of athletic shoes, or the type that will give them the best opportunity to excel?
The ATS HeartCheck is one of only a handful of screening programs that utilizes medical and family history questionnaire, weight, height, blood pressure, heart rate, electrocardiogram (ECG), and echocardiogram (ECHO) on every participant in the evaluation for heart abnormalities; all under the direction of a Pediatric Cardiologists. After all, where do you draw the line in protecting your child, and what medical conditions are OK for them to have without you knowing?
Author: Eric Schroeder has spent the last 25 years in healthcare with an emphasis on cardiovascular testing, committing to use his knowledge to educate, create awareness, and screen for heart issues facing today’s youth. Through his work, Eric has become a leader in providing high-quality screening of undiagnosed heart conditions in student athletes and young people. Follow him on Twitter at @EasyE520.