INTRODUCTION
Sudden cardiac death (SCD) is the leading cause of death during exercise and accounts for nearly 75% of collegiate deaths during exertion.1 A recent study of National Collegiate Athletic Association Athletes (NCAA) found the overall incidence of SCD to be 1:43 000, meaning that at least 10-15 cardiac-related deaths occur in this population annually. Higher risk subgroups include males (3.02/100 000), NCAA Division I football athletes (3.95/100 000), black athletes (5.65/100 000), and Division I basketball athletes (33.33/100 000).1
Although there is universal agreement that cardiovascular screening should be performed in athletes, there is international debate surrounding the optimal screening strategy. The currently endorsed protocol by the American Heart Association (AHA) includes a 12-element history and physical examination2 (Table 1). However, limitations of this strategy were highlighted in an autopsy-based American study where only 1 athlete (0.9%) out of 115 cases of SCD was correctly identified by traditional screening methods.3 In fact, studies have demonstrated that the majority of SCD victims do not have warning signs or symptoms, and cardiac arrest is the first manifestation of disease in up to 80% of cases.2 As such, the European Society of Cardiology, International Olympic Committee, Federation de Internationale de Futbal, and many professional US sporting organizations endorse an electrocardiogram (ECG)-based protocol.
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TABLE 1: The 12-Element AHA Recommendations for Preparticipation Cardiovascular Screening of Competitive Athletes
Some collegiate athletic programs screen athletes with an ECG.4 However, the prevalence of ECG screening among college sporting organizations is unknown. The purpose of this study was to determine the cardiovascular preparticipation examination (PPE) screening practices among college team physicians, across all levels, and to determine what barriers exist to improved screening in the college athletic population.
METHODS
The American Medical Society for Sports Medicine (AMSSM) is the largest collection of sports medicine physicians in the United States. Membership includes sports medicine physicians who care for athletes at all levels including those in the professional, collegiate, and high school settings. Members of AMSSM include not only attending sports medicine physicians but also sports medicine fellows, primary care residents, and medical students.
For the present study, an electronic mail with a link to a 9-item survey was sent to the entire AMSSM membership. The survey was administered mid-fall of 2012. Two reminder e-mails were sent out at 2 weeks and 6 weeks. The survey was open for 8 weeks.
Members were included only if they were college team physicians at any level of play. Sample size analysis determined that a total of 150 respondents were needed to detect a 5% difference in screening patterns of upper and lower divisions with a power of 0.80 and an alpha of 0.05. Descriptive statistics were used for demographic variables and χ2 analysis for outcome measures.5 No incentives for participation were provided. The study was approved by the Institutional Review Board of Eisenhower Army Medical Center and by the Research Committee of the AMSSM.
RESULTS
Six hundred thirteen AMSSM members identified themselves as college team physicians. Of those, 224 (36.5%) responded, including: NCAA Division I: 146 [42.9% (146/340) of all Division I athletic programs], Division II: 41, Division III: 27, National Association of Intercollegiate Athletics: 8, and Junior College: 2 (Table 2). The majority of the team physicians were from the Midwest (29.9%) (Table 3). A total of 58.9% of respondents performed more than 50% of the PPEs at their institution with 27.2% performing 100% of PPEs. The majority (78%) of schools conducted the AHA 12-element history and physical examination only, whereas the others added ECG or echocardiogram. Division I institutions were more likely to add an ECG or echocardiogram (30%) to their PPE compared with lower divisions (P < 0.001) (Figure 1). Those Division I schools using noninvasive cardiac screening (NICS) were more likely to do so for all athletes (P < 0.001) or for revenue generating sports athletes (P < 0.001), whereas other institutions did so only for high-risk subgroups (P < 0.01) (Figure 2). Division I institutions not using NICS cited lack of evidence (71%) and high cost (64%) as barriers, whereas other institutions not using NICS believed that it was not cost effective (P = 0.01) (Figure 3). Lower division schools would consider adding an ECG if it cost less (P = 0.01) or if there were more local expertise in athlete-specific interpretation standards (P = 0.04) (Table 4). Nearly 80% of all respondents would add an ECG if evidence for its use was strengthened.
TABLE 2: Level of Team Coverage
TABLE 3: Demographics
FIGURE 1: Responses to “What Method of Screening is Conducted?”
FIGURE 2: Responses to “If performing an ECG, who do you perform one on?”
FIGURE 3: Responses to “If not performing ECG, why?”
TABLE 4: Would Consider Adding Noninvasive Cardiac Screening*
DISCUSSION
The current recommendation for screening by the NCAA for all divisions is to perform the AHA 12-element history and physical examination (blood pressure and auscultation) on entry to college and an updated medical history yearly.6 Many large-scale studies have demonstrated a lack of sensitivity and specificity with this traditional approach and both medical and sporting organizations are searching for improved cardiovascular screening protocols.7 The relatively high rate of SCD in NCAA athletes occurs despite the majority (78%) of college team physicians using the current AHA-based history and physical examination—therefore, updated and standardized cardiovascular screening methods must be considered.
Approximately 95% of individuals with hypertrophic cardiomyopathy demonstrate abnormalities on ECG8 and the negative predictive value of the ECG approaches 100% for 3 of the most common causes of SCD (hypertrophic cardiomyopathy, long QT syndrome, and Wolff Parkinson White syndrome).9 Although the ECG may not detect every cardiac abnormality in athletes (eg, coronary artery anomaly, bicuspid aortic valve), many high-level college athletic programs and professional sports leagues are already using NICS (ECG or echocardiogram). Our study aimed to delineate the incorporation of NICS practices among all types of college athletic programs and barriers to possible implementation.
A recent study of Division I collegiate football programs found that nearly 50% of these teams routinely incorporate ECG into their PPEs.4 Consistent with these findings, our data demonstrate the use of NICS in nearly one-third all NCAA Division I athletic programs (Figure 1). However, differences did exist in the types of athletes screened with NICS methods. Division I team physicians who currently use NICS screen either all athletes or only revenue generating sports athletes. Team physicians among lower level teams that use NICS only perform it on high-risk athletes (Figure 2). These results suggest that there is a possible risk versus cost-benefit factor considered when implementing advanced screening. Further supporting this statement was the finding that lower level schools would consider adding NICS if it were more cost effective.
Barriers to routine NICS implementation included potential high cost, perceived lack of evidence, or limited physician expertise in athlete ECG interpretation (Figure 3). Unfortunately, studies consistently demonstrate that screening athletes by history and physical alone is the least cost-effective strategy.10–12 The evidence, and subsequent cost-effectiveness of ECG as a screening tool, is significantly improved when modern criteria are used to guide ECG interpretation. Using modern interpretation standards, Marek et al13 demonstrated a total true-positive rate of only 2.5% when screening over 32 000 high school students and student athletes. Similarly, a prospective study of over 1600 collegiate athletes, from 10 NCAA Division I institutions, found a false-positive rate of only 3.0% when using modern ECG interpretation criteria. Interestingly, the false-positive rate in this investigation for the standardized AHA-based cardiovascular history was found to be 10-fold higher (32.8%).14 Further studies are needed to understand the feasibility of implementing advanced cardiovascular screening modalities at all NCAA division levels (1, 2, and 3) before it is offered on a large scale.
To promote physician education of modern ECG interpretation criteria, an international expert consensus panel met to develop the “Seattle Criteria” and an online learning module.15 These educational initiatives will increase expertise for physicians who wish to incorporate an ECG into their current screening protocols.
FUTURE CONSIDERATIONS
For prevention of sudden cardiac arrest, a comprehensive approach must be taken. This includes identifying predisposing conditions and offering early intervention for those deemed high risk to improve survival. The alarmingly high rate of SCD in the collegiate athletic population requires a reevaluation of screening protocols, logistics, methodologies, and intervals. Importantly, physicians should remember that even the most rigorous screening protocols may miss cases of underlying cardiac pathology or commotion cordis, which occurs in structurally normal hearts. As such, emergency action plans must be in place during athletic events that involve prompt recognition of sudden cardiac arrest, delivery of high quality cardiopulmonary resuscitation (CPR), and early defibrillation with an automated external defibrillator (AED).
LIMITATIONS
A major strength of this study is that it is the first to assess PPE practices across all collegiate divisions and the study significantly adds to our understanding of NICS use in high-level athletes. However, there are several limitations of this study. The survey was distributed to AMSSM members, and although they represent the largest body of team physicians, the study did not evaluate athletic trainers or orthopedic surgeons, who may have added insight into institutional screening policies and procedures. Although more than 43% of all NCAA Division I team physicians were surveyed, greater than 50% of team physicians did not respond, which may limit generalizability. Only 1 agency (AMSSM) was surveyed, which may represent a sampling bias. There was a strong sampling from the Midwest compared with other regions, which may add regional bias. Finally, because this was a survey study, there may be some recall bias introduced into the results.
CONCLUSIONS
Many NCAA Division I programs already use an ECG inclusive PPE to screen athletes, while a significant portion of lower division schools add ECGs for athletes deemed high risk. Increased use of these modalities suggests limitations of traditional PPE screening methods. Electrocardiogram increases the sensitivity and specificity of screening; however, routine implementation of ECG screening would require considerations surrounding cost and physician education/training. Further research is needed to address potential concerns of team physicians who wish to integrate an ECG screening program into their institutions. Infrastructure development, such as physician education in athlete-specific ECG interpretation standards, is needed before ECG use becomes more widespread.
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