Published 3 July 2008, doi:10.1136/bmj.a346
Cite this as: BMJ 2008;337:a346

Research

Cardiovascular evaluation, including resting and exercise electrocardiography, before participation in competitive sports: cross sectional study

¹ Department of Medical and Surgical Critical Area, Thrombosis Centre, University of Florence, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy, ² Center for the Study at Molecular and Clinical Level of Chronic, Degenerative and Neoplastic Diseases to Develop Novel Therapies, University of Florence, Italy, ³ Institute of Sports Medicine, Florence, Italy, ⁴ Don Carlo Gnocchi Foundation, IRCCS, Florence, Italy

Abstract

Objective To evaluate the clinical usefulness of complete preparticipation cardiovascular screening in a large cohort of sports participants.

Design Cross sectional study of data over a five year period.

Setting Institute of Sports Medicine in Florence, Italy.

Participants 30 065 (23 570 men) people seeking to obtain clinical eligibility for competitive sports.

Main outcome measures Results of resting and exercise 12 lead electrocardiography.

Results Resting 12 lead ECG patterns showed abnormalities in 1812 (6%) participants, with the most common abnormalities (>80%) concerning innocent ECG changes. Exercise ECG showed an abnormal pattern in 1459 (4.9%) participants. Exercise ECG showed cardiac anomalies in 1227 athletes with normal findings on resting ECG. At the end of screening, 196 (0.6%) participants were considered ineligible for competitive sports. Among the 159 participants who were disqualified at the end of the screening for cardiac reasons, a consistent proportion (n=126, 79.2%) had shown innocent or negative findings on resting 12 lead ECG but clear pathological alterations during the exercise test. After adjustment for possible confounders, logistic regression analysis showed that age >30 years was significantly associated with an increased risk of being disqualified for cardiac findings during exercise testing.

Conclusions Among people seeking to take part in competitive sports, exercise ECG can identify those with cardiac abnormalities. Follow-up studies would show if disqualification of such people would reduce the incidence of CV events among athletes.

Introduction

Preparticipation screening is the systematic practice of evaluating sports participants before competition to detect cardiovascular abnormalities and thus prevent sudden death or progression of disease.^{1 2} In Italy, such screening constitutes an established medical programme that has been implemented for more than 25 years.³ Over the past few decades, clinicians and experts have debated its clinical usefulness in identifying those at high risk.^{4 5 6} Corrado et al recently showed a significant decrease in the incidence of sudden death in young Italian athletes who had undergonesuch screening.⁷ The European Society of Cardiology and the International Olympic Committee, taking note of Italy’s 25 years of experience, underlined the need for medical examination for young competitive athletes before they take part in organised sports programmes,^{1 8} though the recently updated recommendations of the American Heart Association do not support this medical perspective.²

We analysed data from the Institute of Sports Medicine in Florence, Italy, on cardiovascular evaluation, including resting and exercise electrocardiography, in a large unselected population of sports participants.

Methods

Study population
The study population included 30 065 participants who were referred, during a five year period (2002-6), to the Institute of Sports Medicine to obtain eligibility to take part in competitive sports. All participants were examined with first line investigations, as required under Italian law.⁹ Since 1982, people participating in all officially sanctioned sports must undergo medical screening that includes personal and family history, physical examination, and resting and exercise 12 lead electrocardiography (ECG).⁹ Additional tests are requested only for those with positive results in the initial evaluation and are performed by major hospitals or centres other than the institute. Criteria for positive family and personal history, physical examination, and ECGs are those established by Italian protocol and are reported elsewhere.^{7 9 10} All participants gave written informed consent.

Statistical analysis
Statistical analysis was performed with SPSS (Chicago, IL, USA) software for Windows (version 13.0). Continuous variables were expressed as means and standard deviations (SD) for parametric data or median and range for non-parametric data. We used the non-parametric Mann-Whitney test for comparison between single groups, the Kruskal-Wallis test for comparison among different groups, and ² to test comparisons between proportions. After adjustment for possible confounders (sex, age group (<30, 30-50, >50), body mass index (BMI), family history, systolic blood pressure, diastolic blood pressure, smoking habits (yes or no), heart rate, type of sport practised), we carried out logistic regression analysis to evaluate possible predictors of disqualification among athletes with a normal resting ECG pattern. P value <0.05 indicated significance.

Results

Characteristics of the study population
The study population included 30 065 participants, with significantly (P<0.001) more men than women (23 570 (78.4%) v 6495 (21.6%)). The mean age was 30.7 (SD 14), with a range of 5-92; 33 were aged over 80. Nearly 40% of the total study population were aged over 30, and 98% were white. Men were significantly older than women (28.4 v 24.6; P<0.001) and included a significantly higher proportion of smokers (13.2% v 10.3%; P<0.001). More than half of the participants were reported to have a sedentary job (56.2%), with no significant difference between men and women. Most people spent an average of four to six hours a week doing sports activities (50.9%), whereas the rest were reported to spend less than four or more than six hours a week (20.7% and 28.4%, respectively) taking part in sports.

Participants took part in over 30 different sporting disciplines, the main ones being football and volleyball (31.3% and 17.7%, respectively). Other leading sports were cycling (6.7%), athletics (5.9%), and basketball (5.8%) among men and swimming (6.5%), athletics (6%), and gymnastics (4.2%) among women.

Personal and family history indicated cardiac abnormalities in less than 0.5%, whereas physical examination reported pathological findings in about 3%.

Resting 12 lead electrocardiography
Abnormalities on resting ECG were present in 1812 (6%) participants, 1570 (6.7%) men and 242 (3.7%) women (P<0.001) (table 1). The most common abnormalities were sinus bradycardia (2.9%) and complete (1.1%) or incomplete (0.7%) right bundle branch blocks, which, together with the type I atrioventricular block and early polarisation pattern, can be considered as innocent modifications that occur in the "athlete’s heart." These abnormalities accounted for over 80% of the total anomalies (n=1464). A distinctly abnormal pattern was found in the remaining participants (348; 1.2%), the most common being ST-T segment alterations and premature ventricular and supraventricular beats. There was a higher prevalence of innocent ECG changes in men than in women, with the exception of type I atrioventricular block.

View this table: [in this window] [in a new window]   Table 1  Results of 12 lead resting and exercise electrocardiography in people screened before taking part in competitive sports. Figures are number (percentage) of participants

 
With regard to age, participants with reported ECG abnormalities were significantly older than those with a normal ECG pattern (31.1 (SD 13.8) v 29.1 (SD 13.1), P<0.001). Almost half of the population with ECG irregularities comprised participants aged 30-50 (46.9%), with the remaining portion mostly being those aged under 30 (33.6%).

Exercise 21 lead electrocardiography
All participants underwent exercise ECG (table 1), and abnormalities were found in 1459 (4.9%), with a higher prevalence in women than men (521 (8%) v 938 (3.9%)). Those with abnormalities were significantly older than those with normal patterns (30.9 (SD 12.1) v 24.9 (SD 9.9), P<0.001), and an equal proportion (48.9%) were aged over 30. The most prevalent anomalies were premature ventricular and supraventricular beats, accounting for over 65% of the total abnormalities, with a significantly higher prevalence among women than men (P<0.001). The remaining abnormalities comprised non-sustained and sustained ventricular tachycardia, ST-T segment alterations, and cardiac conduction disorders. Notably, only 232 (12.8%) participants with abnormalities on resting ECG also showed these abnormalities on exercise ECG, but exercise ECG showed cardiac anomalies in 1227 participants (939 men; 288 women; mean age 30.7 (SD 11.9)) in whom resting ECG had shown a normal pattern. In particular, the most prevalent cardiac abnormalities found on stress testing comprised findings suggestive of coronary heart disease and arrhythmias.

Eligibility and screening
After screening, 196 (0.6%) people were considered ineligible to take part in competitive sports (182 (0.7%) men and 14 (0.2%) women; mean age 37 (SD 12.3)). In total 159 (81.6%) athletes were disqualified because of cardiac abnormalities, and 37 were disqualified for other reasons (table 2).

View this table: [in this window] [in a new window]   Table 2  Causes of disqualification from competitive sports at the end of screening

 
By analysing disqualifications according to abnormalities found at resting and exercise ECG, we found that, among the 159 participants disqualified because of cardiac abnormalities, personal history or physical examination, or both, had suggested problems in only six (3.7%) and a large proportion (126, 79.2%) had a normal pattern on resting ECG. Conversely, almost all the disqualified participants showed some cardiac abnormalities during the exercise ECG. Indeed, in 56 participants with a normal resting ECG, exercise testing showed some potentially fatal cardiac disorders such as arrhythmias and coronary heart disease that resulted in disqualification from competition.

Finally, we performed a logistic regression analysis to investigate possible predictors of disqualification among the group of participants with a normal resting ECG. After adjustment for possible confounders we found that the risk of being disqualified increased significantly with age. Participants aged over 30 had a significantly increased risk of showing cardiac abnormalities on exercise ECG, thus resulting in disqualification from competition (table 3).

View this table: [in this window] [in a new window]   Table 3  Predictors of disqualification among athletes with normal findings on resting ECG

 

Discussion

Findings from this cross sectional study, although only preliminary and not supported by follow-up analyses, support the inclusion of resting and exercise ECGs to detect cardiac abnormalities such as ventricular and supraventricular arrhythmias and coronary heart disease among people taking part in competitive sports, especially those who are middle aged and older. A consistent proportion of people disqualified for cardiac disorders showed innocent or negative findings on resting 12 lead ECG but clear pathological alterations on exercise ECG.

Over the past few decades, there has been increasing interest in the role of cardiovascular screening to identify potentially fatal cardiac disorders among athletes before they take part in competitive sports.^{1 2 3 4 5 6 7 11 12} , Routine use, however, is far from accepted and still raises several important unresolved questions of ethical and practical importance. First of all, the clinical importance of changes in the athlete’s heart on ECG is not fully established. In our analysis, as in previous studies,¹² the most prevalent abnormalities on resting ECG were typical of an athlete’s heart. In this scenario, the implementation of ECG screening would probably result in a large number of borderline and false positive results, leading to additional tests to resolve the clinical ambiguity, worry and emotional stress for the participants, and considerable financial costs. On the other hand, some participants with innocent abnormalities showed a clear pathological pattern on exercise ECG, resulting in disqualification from competition. This is in line with results of Pelliccia et al, who recently showed that an abnormal repolarisation pattern, generally regarded as an innocent consequence of athletic conditioning, might represent the initial expression of underlying disease, thus meriting further clinical consideration.¹³

The cost of such a programme is also important. In Italy it costs an estimated 30 (£24, $47) per participant. The implementation of such a programme would definitely result in additional costs for the National Health Service and for the population as a whole. Nevertheless, decreasing the risk of sudden death among competitors is extremely important as it has a considerable impact on both lay and medical communities because of the broadly held view that athletes constitute the healthiest people in society.

Limitations
Because of the observational design of this study, we were unable to show if these clinical evaluations are effective in reducing the risk of mortality or incidence of cardiac accidents in sports participants. Only a prospective analysis of these data will help us to test this hypothesis. None the less, some previous studies have reported on the clinical efficacy of such cardiovascular screening on reducing sudden death among athletes.^{7 11 13} Moreover, results of second line investigations in participants with a positive screening result are not available, making it difficult to interpret the real diagnostic power of baseline and exercise ECGs, as well as the important matter of false positive results.

Our study, however, provides relevant information especially for middle aged and elderly people participating in sports, and shows a significant prevalence of some potentially fatal cardiac diseases such as coronary heart disease and hypertension.

What is already known on this topic Cardiovascular events during sports are tragic occurrences that attract public and media attention Evaluation of competitive athletes before participation might reduce the risk of cardiovascular death or events during competition What this study adds The inclusion of resting and exercise electrocardiography to the standard medical evaluation of sports participants helps to identify those at high risk Exercise electrocardiography can show clear pathological findings in participants with negative or innocent findings at physical examination and resting electrocardiography

Cite this as: BMJ 2008;337:a346

---

We thank James Wood for his valuable contribution in the revision of the manuscript.

Contributors: All the authors participated in study design, analysis, interpretation of results, drafting of the article, and approval of the final draft. FS is guarantor.

Funding: None.

Competing interests: None declared.

Ethical approval: Research ethics board of the Institute of Sports Medicine of Florence.

Provenance and peer review: Not commissioned; externally peer reviewed.

References

1. Corrado D, Pelliccia A, Bjornstad HH, Vanhees L, Biffi A, Borjesson M, et al. Cardiovascular pre-participation screening of young competitive athletes for prevention of sudden death: proposal for a common European protocol. Eur Heart J 2005;26:516-24.[Abstract/Free Full Text]
2. Maron BJ, Thompson PD, Ackerman MJ, Balady G, Berger S, Cohen D, et al. Recommendations and considerations related to preparticipation screening for cardiovascular abnormalities in competitive athletes: 2007 update. Circulation 2007;115:1643-55.[Free Full Text]
3. Di Luigi L, Pelliccia A, Bonetti A, Francavilla G, Ganzit GP, Veicsteinas A, et al. Clinical efficacy and preventive role of the pre-participation physical examination in Italy. Med Sport 2004;57:243-70.
4. Chaitman BR. An electrocardiogram should not be included in routine pre-participation screening of young athletes. Circulation 2007;116:2610-5.[Free Full Text]
5. Myerburg RJ, Vetter VL. Electrocardiograms should be included in pre-participation screening of athletes. Circulation 2007;116:2616-26.[Free Full Text]
6. Pelliccia A. The preparticipation cardiovascular screening of competitive athletes: is it time to change the customary clinical practice? Eur Heart J 2007;28:2703-5.[Abstract/Free Full Text]
7. Corrado D, Basso C, Pavei A, Michieli P, Schiavon M, Thiene G. Trends in sudden cardiovascular death in young competitive athlete after implementation of a pre-participation screening program. JAMA 2006;296:1593-601.[Abstract/Free Full Text]
8. IOC Medical Commission, International Olympic Committee. Sudden cardiovascular death in sport. Lausanne recommendations: pre-participation cardiovascular screening. 2004. http://multimedia.olympic.org/pdf/en_report_886.pdf
9. DM 18/2/1982 con norme integrative del DM 28/2/1983 "Norme per la tutela della attività sportive agonistica e non agonistica". http://www.fmsitv.org.
10. Delise P, Guiducci U, Zeppilli P, D’Andrea L, Proto C, Bettini R, et al. Consensus document by the Italian Society of Sports Cardiology; Italian Association of Out-of-Hospital Cardiologists; Italian Association of Hospital Cardiologists; Italian Federation of Sports Medicine. Cardiological guidelines for competitive sports eligibility. Ital Heart J 2005;6:661-702.[Medline]
11. Pelliccia A, Di Paolo FM, Corrado D, Buccolieri C, Quattrini FM, Pisicchio C, et al. Evidence for efficacy of the Italian national pre-participation screening programme for identification of hypertrophic cardiomyopathy in competitive athlete. Eur Heart J 2006;27:2196-200.[Abstract/Free Full Text]
12. Pelliccia A, Culasso F, Di Paolo FM, Accettura D, Cantore R, Castagna W, et al. Prevalence of abnormal electrocardiograms in a large, unselected population undergoing pre-participation cardiovascular screening. Eur Heart J 2007;28:2006-10.[Abstract/Free Full Text]
13. Pelliccia A, Di Paolo FM, Quattrini FM, Basso C, Culasso F, Popoli G, et al. Outcomes in athlete with marked ECG repolarization abnormalities. N Engl J Med 2008;358:152-61.[Abstract/Free Full Text]

(Accepted 6 June 2008)

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

Relevant Articles

Olympic dreams

Domhnall MacAuley
BMJ 2008 337: a739. [Extract] [Full Text]

Sudden cardiac death in young athletes

Jonathan A Drezner and Karim Khan
BMJ 2008 337: a309. [Extract] [Full Text]

This article has been cited by other articles:

• Drezner, J. A, Khan, K. (2008). Sudden cardiac death in young athletes. BMJ 337: a309-a309 [Full text]  

Rapid Responses:

Read all Rapid Responses

Echocardiography would even perform better on a population-based level

Johannes G. Scholl, et al.
bmj.com, 4 Jul 2008 [Full text]

Clinical evaluation of young athletes to prevent syncope or sudden death prior to exercise field events

Munir (Mounir) E Nassar
bmj.com, 9 Jul 2008 [Full text]

Issues for Pre-participation Screening in the U.K.

Alan T Rankin
bmj.com, 12 Jul 2008 [Full text]

How is "athlete"defined?

Avril F Danczak
bmj.com, 14 Jul 2008 [Full text]

Taking prevention to a relative curative level.

Munir (Mounir) E. Nassar
bmj.com, 21 Jul 2008 [Full text]

Mandatory ECG Screening of Athletes

Roy J. Shephard
bmj.com, 10 Aug 2008 [Full text]