CardioExchange Archive

CardioExchange’s Erica Spatz asks William O. Roberts and Steven D. Stovitz about their research, published in JACC, on the incidence of sudden cardiac death among high school athletes in Minnesota.

THE STUDY

Researchers retrospectively assessed the incidence of sudden cardiac death (SCD) during Minnesota State High School League (MSHSL) games and practices. Among nearly 4 million athletes (age 12–19; 55% boys) who were screened every 3 years using a state-approved preparticipation examination (PPE) form, 4 SCDs occurred, all in boys (2 during cross country, 1 during basketball, 1 during wrestling). The overall incidence of SCD was 0.24 per 100,000 athlete-years during a period of 19 years.

THE INTERVIEW

Spatz: You found a very low incidence of SCD among high school students in Minnesota who were screened using a state-approved PPE form. What are the implications of these findings?

Roberts and Stovitz: The Preparticipation Physical Evaluation Monograph cited in our study is the work of 6 organizations, including the American College of Sports Medicine, the American Academy of Family Physicians, and the American Academy of Pediatrics. It uses the 12-point cardiovascular preparticipation screening question set from the American Heart Association and the participation recommendations from the current Bethesda Guidelines. The question set for the Minnesota standardized form is used statewide by all health professionals who do the exams. The Minnesota form is reviewed and updated annually by the MHSHL Sports Medicine Advisory Committee to reflect the most recent changes. Notably, the questions on the form have not been derived from or subjected to scientific scrutiny; they are based on expert opinion.

The implications of our findings are fourfold: First, this long-term cohort of high school athletes screened every 3 years with a standard PPE form had a very low rate of SCD during activities for which they were screened. Second, this type of form, if used nationwide, may be effective in screening for SCD at the high school level (with some caveats we discuss below). Third, high school level athletes may be at less risk than college and older athletes, so we should focus research efforts on narrower age ranges than the broad categories of <30–35 and >35–40. Fourth, we found that most high school athletes participate in 2 to 3 sports each year, at least in Minnesota.

Spatz: Describe the Preparticipation Physical Evaluation Monograph. Which groups or risk factors might prompt further diagnostic workup, including an ECG?

Roberts and Stovitz: The PPE Monograph is a comprehensive look at athlete preparticipation issues, including the cardiovascular exam. It focuses mainly on competitive athletes age 12 to 25 but does extend to older and younger athletes.

The cardiovascular questions are grouped into two important areas: “Heart Health Questions About You” and “Heart Health Questions About Your Family.” Other questions address asthma, concussion, musculoskeletal problems, eating issues, and other matters of concern for athletes and parents. The provider is also prompted to address depression, drugs, tobacco, alcohol, sex, and risky behaviors that are not likely to be disclosed by adolescent athletes on a form signed by a parent.

With respect to the cardiovascular questions, a “yes” or positive response should initiate a set of secondary questions outlined in the monograph; in most instances, the athlete is moved on to a case-finding cardiovascular evaluation starting with an ECG. The monograph addresses the educational gap in interpreting findings such as syncope, which may be misinterpreted as a neurologic sign or even ignored.

Spatz: Why do you think you found lower rates of SCD in your study than in previously studied populations (e.g., Italian athletes and NCAA athletes)?

Roberts and Stovitz: Both the Italian and NCAA data sets include older athletes, and some cardiac problems manifest in older athletes. The intensity of training and activity is likely greater in the NCAA (especially Division I) and in young-adult athletes. Also, the genetic predisposition to some cardiac problems may differ among Italian athletes, U.S. college athletes, and Minnesota high school athletes. Also note that our study does not address all the exercise-related cardiac deaths in this age group, only the incidents that met the cardiovascular criteria for catastrophic insurance payments.

Spatz: Should your results, based on high school students in Minnesota, be generalized to other high school populations?

Roberts and Stovitz: We do not think the data can be extrapolated to all U.S. high school athletes, primarily because Minnesota has a lower proportion of African Americans than many other states and a larger proportion of people of northern European heritage. Given that African Americans have a higher rate of hypertrophic cardiomyopathy and SCD than European Americans, SCD rates among high school athletes in other states may be higher. We encourage other researchers to evaluate how states with different ethnic and racial mixes compare with Minnesota. In addition, it would be interesting to see how our data compare with those from states that require PPEs each year or every other year rather than every third year. Given that an increasing number of high school–age athletes now compete for club teams rather than their high schools, future research may need to account for club sport participation. Finally, the spectrum of sports participation in Minnesota may differ from that in other states, even though the average intensity of activity is likely to be similar.

JOIN THE DISCUSSION

Do these data from Minnesota change your thinking about SCD incidence among high school athletes and about how they should be screened before participating in sports?