Over the years sudden death (SD) in young athletes has become an increasingly hot-button issue that has attracted interest from not only concerned parents but from those in the cardiovascular field. While the American Heart Association has proposed its own guidelines recommending a pre-participation history and physical examination for young athletes intent on joining competitive sports, implementing routine use of an electrocardiogram (ECG) has never been a part of such parameters.

A study published Feb. 26 in the Journal of the American College of Cardiology assessed the implications for a nationwide screening program for conditions causing sudden cardiac death (SCD) and found that "over one-fifth of young individuals would require further cardiac investigation if an ECG-based screening program were implemented using current recommendations," while a separate study defined the incidence and causes of death in college student athletes and found "a substantial minority of confirmed cardiovascular deaths would not likely have been reliably detected by preparticipation screening with 12-lead ECGs."

The first study, led by Navin Chandra, BSc, investigated the prevalence of potentially abnormal ECG patterns in young individuals, and looked at ECGs performed on 7,764 non-athletes (defined as someone not involved in regular competitive team or individual sports, including sedentary individuals and recreational exercisers) aged 14-35 years-old and 4,081 athletes (defined as individuals competing at the regional, national, international level). Their scans were analyzed for Group-1 (training related) and Group-2 (potentially pathological) patterns. Results showed group-1 patterns were unsurprisingly prevalent among athletes, and common in the non-athlete group (87.4 percent and 49.1 percent respectively).

Meanwhile, Group-2 ECG patterns were present in both cohorts (33 percent in athletes and 21.8 percent in non-athletes). Anne Curtis, MD, FACC, Department of Medicine, Division of Cardiology, University of Buffalo, explains in an editorial comment that "echocardiographic evaluation of all 784 non-athletes with Group-2 ECG patterns suggestive of a cardiomyopathy or structural cardiac abnormality identified a normal heart in the majority (84 percent) of individuals. Only two percent of non-athletes with Group-2 ECG patterns had echocardiographic findings that could be consistent with a mild cardiomyopathy, and the rest had incidental findings that would not impact sports participation." Given the low event rate of cardiomyopathy, Chandra and his co-authors ultimately felt their finding to have significant implications on the feasibility and cost-effectiveness on a nationwide screening program.

Mirroring this pragmatic point of view, a separate study led by Barry Maron, MD, FACC, Hypertrophic Cardiomyopathy Center, Minneapolis Heart Institute Foundation, Minneapolis, MN, assessed databases — including autopsy reports — from both the U.S. National Sudden Death in Athletes Registry and National Collegiate Athletic Association to define the incidence and causes of death in college student athletes.

Maron and his researchers found that from a total number of 4,052,369 student athletes participating in 30 intercollegiate sports from 2002 to 2011, 182 cases of SD were recorded. Of those deaths, 47 were confirmed to be from a cardiovascular abnormality. Of those 47, 28 would have been likely identified or suspected by an ECG screening.

Taking in these two studies as a whole, the infrequency in which SD occurs among a young and relatively active population speaks volumes. "Despite the tragedy of losing even one young individual to SCD, mass ECG screening programs prior to sports participation, especially in recreational athletes, are neither cost effective nor sustainable," writes Curtis. "The most common finding by far turns out to be a false positive leading to additional testing before most individuals are found to be normal and cleared to exercise. The best way to avoid that scenario is not to screen with ECGs in the first place."

Keywords: Athletes, Prevalence, Incidence, Registries, Cardiovascular Abnormalities, Cardiomyopathy, Hypertrophic, Sports, Electrocardiography, Physical Examination, Death, Sudden, Cardiac