EVIDENCE-BASED ANSWER
PROBABLY NOT. Although some European and international experts recommend that all athletes undergo preparticipation electrocardiogram (EKG) screening, it’s unclear whether screening reduces the risk of sudden cardiac death (SCD); US experts don’t recommend it routinely for school-aged athletes (strength of recommendation [SOR]:C, observational studies and expert opinion).
However, further cardiac work-up, including EKG, is indicated if concern exists about increased cardiovascular risk (SOR: C, expert opinion).
Evidence summary
SCD in athletes is a rare event; researchers estimate the annual incidence at 0.5 to 2 per 100,000 athletes per year.1,2 The rarity of SCD, lack of registries recording cases, multiple causes, and varying demographics limit accurate estimation of its incidence.3 Experts also debate whether the ability of a single EKG to detect a potentially lethal arrhythmia outweighs the expense and potential harm of false-positive results. No randomized controlled trials have assessed the efficacy of preparticipation screening, with or without EKG, to reduce SCD. The major studies evaluating this issue are observational and retrospective.
An Italian study suggests lower SCD mortality with EKG screening
An Italian observational study of 33,735 athletes reported results of a 25-year program of mandated SCD screening (1979-2004).4 Researchers found that the incidence of sudden death was 89% lower at the end of the screening program (0.4/100,000 athletes/year), compared with the baseline (3.6/100,000 athletes/year).
The program used highly trained sports medicine physicians and supplemented the history and physical examination with universal EKG screening. Screening began at 12 to 14 years of age and was repeated regularly as long as the athlete was engaging in competition. The incidence of SCD in nonathletes (0.79/100,000 nonathletes/year) didn’t change over the 25 years of the study.
Limitations of the study include the lack of a concurrent control group of unscreened athletes and time-dependent bias, also known as immortal time bias. (Studies with time-dependent outcomes in which the test of interest, such as EKG screening, and the outcome analyzed, such as SCD, occur during the same period are susceptible to immortal time bias. Athletes who may have died suddenly during the prescreening period would never have made it to the first screening, so the group of athletes who made it alive to the first screening already represented a selected lower-risk population whose characteristics contributed to the lower mortality rates in the postscreening period.)
Other study limitations included baseline differences in male-to-female ratio (82% male) and age range (12-35 years). In addition, the study used a short measurement time (approximately 3 years) to establish a baseline SCD incidence, resulting in a higher incidence than the average in other studies.
An Israeli study suggests otherwise
An uncontrolled observational study done in Israel compared the number of SCDs before and after implementation of a mandatory nationwide screening program for all athletes.5 The screening protocol included a medical questionnaire, physical examination, resting EKG, and exercise stress test. Researchers estimated the SCD incidence by scrutinizing newspaper reports of sudden deaths in competitive athletes for 2 time periods: 12 years before (1985-1997) and 12 years after (1997-2009) the intervention.
They identified 24 presumed cardiac deaths, all in male athletes 12 to 44 years of age (mean 23.9 years). The incidence of SCD in the athletes before and after this protocol was 2.54 and 2.66/100,000 athletes/year, respectively (P not significant).
An advantage of this study is the longer period used to estimate SCD incidence (12 years compared with approximately 3 years). A disadvantage is that the researchers calculated the SCD incidence by relying only on media reports rather than on a death registry.
A US comparison study supports the Israeli findings
In the United States, researchers compared SCD rates in high school and college athletes in Minnesota with the rates reported in the Italian study discussed previously.1 They collected mortality data from several sources, including a national death registry, over a similar time period (1985-2007), during which routine EKG screening of Minnesota athletes wasn’t mandated or recommended.
During the 23-year study period, SCD mortality rates in young athletes in Minnesota remained stable at 0.97/100,000 athletes/year (range 0.5-1.3). This rate didn’t differ significantly from the death rate reported at the end of the Italian study.4 The US authors concluded that their data didn’t support the hypothesis that routine EKG screening in young athletes results in lower SCD mortality.1