WASHINGTON — While ECG screenings in school-age athletes may be necessary to reduce risk for sudden cardiac death, there are questions that need to be answered about accuracy of diagnosis, two experts said in a debate held at the American College of Cardiology Scientific Session.
“In a vote from Italian physicians and American physicians, … 74% of Italian physicians voted that the screening should be required and should include history, physical examination and ECG,” Francesco Fedele, MD, professor in the department of cardiovascular, respiratory, nephrology, anesthesia and geriatric science at Sapienza University of Rome and president of the Italian Federation of Cardiology, said during the session. “Otherwise, for American physicians, only 45% vote on this way, and 20% vote that the screening should not be required.”
Fedele said in Italy, 1,000 incidents per year of sudden death occur in people under the age of 35. “In younger [patients], the prevalence [of sudden death] is relatively low, but … in puberty, the prevalence is relatively high,” Fedele said.
Benefits of ECG screenings
Cardiologists in Italy see ECG screening as a mandatory process for young athletes. “In young competitive athletes, [they] must undergo family and personal history, physical examination, ECG and eventually other examinations in order to evaluate the clinical situation,” Fedele said. Many international sporting federations require pre-participation CV screenings including ECG, but the American association does not suggest this inclusion, he added.
Fedele mentioned a study performed by Kimberly G. Harmon, MD, from the department of family medicine, University of Washington, and colleagues, and published in the Journal of Electrocardiology, in which they wrote, “ECG is the most effective strategy for screening [CVD] in athletes, and the use of history and physical exam alone as a screening tool should be reevaluated.” According to Fedele, the end of puberty matches the time when a patient’s ECG is similar to that of an adult patient. Although ECGs are a helpful tool in screening children, Fedele said, “ECG screening is likely to prove less effective as a pre-participation tool than in adult athletes.”
“The lack of expertise and human resources in interpreting ECG in athletic children should also be addressed,” Fedele added. “Until those drawbacks are corrected, the personal and familial history and physical exam remain the cornerstone in the risk assessment of [sudden cardiac death] in children.”
Athletes aren’t the only patients that should be screened for sudden cardiac death. “Many children, adolescents and young adults participate in various levels of play, physical activity, nonorganized competitive sports and intensive physical conditioning programs,” Fedele said. “More than 25 million children and adolescents who do not participate in school-related sports teams, but participate in various physical activities, will be overlooked if ECG screening is limited to athletes.”
Fedele and colleagues completed a study that analyzed ECG screenings from 16,000 Italian participants. Of those, 33% participated in competitive sports. From the total cohort, 21% reported abnormal ECGs and proceeded with level 2 examinations, which included echocardiography, ergometric tests and ECG-Holter. One percent of participants required level 3 examinations such as cardiac MRIs and genetic testing.
“Our research is the largest prospective ECG screening study in young population of post-puberty age,” Fedele said. “For the first time, competitive athletes’, non-competitive athletes’ and non-athletes’ ECG findings were compared. No significant differences were observed between competitive athletes and non-competitive athletes in terms of major and minor ECG abnormalities.”
Fedele said according to one study, adding ECGs to the family history and physical examination portions of screening “would save 2.06 life-years per 1,000 young athletes.
“The benefit of screening goes beyond the identification of the student’s risk of [sudden cardiac death] because it often triggers the evaluation of first-degree relatives who may also be at risk from inherited cardiac diseases.” Fedele said. “Cardiac screening with ECG has the potential of saving additional lives.”
Difficulties with processes
While the cost of saving per human life cannot be valued, “there are too many issues right now to implement universal ECG screening,” Bryan C. Cannon, MD, FACC, FHRS, pediatric cardiology fellowship director at Mayo Clinic, said in his discussion on the disadvantages of ECG screening.
Bryan C. Cannon
Although it’s not required in the United States, countries such as Italy, Japan, Israel, Canada and Taiwan have made ECG screenings mandatory. Bills are in the process of being passed in various states, including Illinois, South Carolina, Texas and Washington.
A study published in 1985 in the Journal of the American College of Cardiology showed “there’s about 5,000 to 7,000 annual [sudden cardiac] deaths in the United States, 5% [of the] deaths [are] in children, and one to eight per 100,000 patient-years,” Cannon said. “During the Italian sports study that I mentioned, there were 265 deaths in unscreened non-athletes.”
ECG screening doesn’t immediately help diagnose a patient with sudden cardiac arrest, as it sometimes develops over time. “If you take a look at these patients, there was a study of 61 family members with the genetic defect,” Cannon said. “Thirty-four percent had a normal echo and ECG when they were first screened, including nine children and 12 adults. When they followed serial echocardiography over the next 6 years, 60% developed new hypertrophy. So if you screen somebody at one point, it may not mean that they don’t have the underlying condition or disease.”
Cannon said substantial ventricular remodeling occurs, but morphologic expression is completed by age 18. “The question is when do we first do the screening? Do we start in elementary school, junior high or high school? And if we do it at that time, how many times and when do we need to repeat this so we don’t miss patients that are potentially at risk.”
False positives, negatives
Another issue with ECG screening is the incidence of false positives, which can vary between 2% and 15%, according to Cannon. “If you take a look at truly elite athletes, about 40% will have an abnormal ECG, but 5% of those will have a structural heart defect.”
A variety of conditions can be missed by ECG screening, including paroxysmal arrhythmias, coronary artery anomalies, Marfan syndrome and cathecolaminergic polymorphic ventricular tachycardia.
“In some cases, there’s no impact [with false positives and false negatives], but there may be a cascade of increasingly expensive or invasive follow-up testing, the potential for missing patients at risk, lengthened exposure time to medical personnel, inappropriate therapy, and both false reassurance of not being affected as well as psychological trauma caused by false belief of having a disease,” Cannon added in his discussion.
Some of the misinterpretations of ECG can be contributed to those read the ECG. There are some states that have approved practitioners such as chiropractors, homeopathic and podiatrists to read the results. At this time, there are no regulations or guidelines on who should be reading the ECGs.
Even with a positive ECG screening, the athlete is occasionally cleared for participation by a family doctor who did not tell the athlete that they have a risk for sudden cardiac death.
Cannon also said cost is a concern, especially since follow-up, which is an important step in the screening process, is often not calculated in these totals.
Fedele added that he and his colleagues calculated the cost of ECGs and follow-up care using their data. If an ECG costs 11 euro plus any additional tests and follow-ups, each year of saved life is an estimated 160 euro, he said.
“The purpose of screening is to save lives and not save money,” Fedele said. – by Darlene Dobkowski
Fedele F. ECG Screening in Athletes: The Great Debate. Presented at: American College of Cardiology Scientific Session; March 17-19, 2017; Washington, D.C.
Disclosure: Cannon reports serving on a Data Safety Monitoring Board for Medtronic and on the board of directors for Mayo Support Services, Texas. Fedele reports no relevant financial disclosures.