Pre-participation ECG screening in military recruits- the IDF experience

1. Pre-participation ECG screening in military recruits- the IDF experience Alon Grossman M.D MHA1,2,3, Alex Prokupetz MHA1,2, Igor Lipchenca MD 4 IAF aero medical center, Tel Hashomer, Israel IDF medical corps Department of Internal Medicine E, Rabin Medical Center Beilinson Campus affiliated to Tel Aviv University Sackler Medical School, Israel Leviev Heart Center, Sheba Medical Center and Tel Aviv University, Tel Hashomer, Israel

2. Introduction • Despite the large numbers of athletes undergoing pre-participation screening, there is a continuing debate regarding the optimal method of screening • The main concern in performing mass ECG screening in athletes is the costly additional work up required based on resting ECG findings

3. Introduction • Professional guidelines in the US do not recommend use of either ECG or echocardiography for screening of college athletes1 • On the other hand, 12-lead ECG has been supported for screening purposes among athletes by the Sport Cardiology section of the European society of Cardiology and Medical Commission of the International Olympic Committee and has been shown to reduce mortality in this population2 1. Maron BJ, Thompson PD, Ackerman MJ, et al. Recommendations and considerations related to pre participation screening for cardiovascular abnormalities in competitive athletes: 2007 update: a scientific statement from the American Heart Association Council on Nutrition, Physical Activity, and Metabolism: endorsed by the American College of Cardiology Foundation. Circulation. 2007; 115:1643-1655 2. Corrado D, Basso C, Pavei A, Michieli P, Schiavon M, Thiene G. Trends in sudden cardiovascular death in young competitive athletes after implementation of a pre-participation screening program. JAMA 2006; 296:1593–1601

4. Background • Recruits to elite units in the IDF undergo pre-participation ECG prior their enlistment • This process has been performed sporadically in the last years but all ECGS are performed at the IAF aero medical Center since January 2010 • All elite units candidates undergo a preliminary medical selection process at the IDF recruitment center (History & PE) • Only those who are physically healthy are allowed to enlist to elite units and only they undergo pre-participation ECG • This population consists of 17-19 years old male subjects

5. Background • All ECGS are evaluated by a single cardiologist • Those requiring further evaluation, complete the evaluation prior to enlistment • A military physician from the IAF aero medical center summarizes the medical evaluation and decides whether the candidate is eligible to enlist to a special unit

6. Aims • To characterize causes of referral to continued investigation based on resting ECG findings • To summarize the additional work-up performed • To summarize the rate of significant findings resulting in disqualification of military candidates in this population

7. Results • 1,455 subjects underwent pre-participation ECG in the year 2010 • 1,388 studies (95.39%) interpreted as normal • 67 referred to further evaluation

8. Causes for referral

9. Additional investigations

10. Clinical Diagnosis

11. example 1

12. Example 2 • ICRBBB with non-specific T wave changes in inferior leads • Echocardiography interpreted as normal • No further w/u required

13. Example 3 • Early repolarization pattern particularly in V2 • Echocardiography-normal • No further w/u required

14. Discussion • Screening for cardiovascular disease among athletes and military candidates is imperative as sudden death is obviously tragic and potentially preventable • Debate continues regarding the optimal method of screening, this ranging from reliance solely on history and physical examination to performance of 12-lead ECG and echocardiography

15. Discussion • The total rate of ECGS defined as abnormal in this cohort was 4.6%, a percentage much lower than previously reported • Yet, even in a previous report by Pellicia et al (8) in which 11.8% of ECGs were interpreted as abnormal, additional evaluation was requested in only 4.8% of ECGs, disregarding some of the findings noted on routine ECG • This rate is similar to that reported in this study and probably represents the true rate of ECG findings requiring further evaluation in young athletes Corrado D, Basso C, Schiavon M, Thiene G. Screening for hypertrophic cardiomyopathy in young athletes. N Engl J Med 1998;339: 364–369 Pelliccia A, Culasso F, Di Paolo FM, Accettura D, Cantore R, Castagna W, Ciacciarelli A, Costini G, Cuffari B, Drago E, Federici V, Gribaudo CG, Iacovelli G, Landolfi L, Menichetti G, Atzeni UO, Parisi A, Pizzi1 AR, Rosa M, Santelli F, Santilio F, Vagnini A, Casasco M, and Di Luigi L. Prevalence of abnormal electrocardiograms in a large, unselected population undergoing pre-participation cardiovascular screening. Eur Heart J 2007; 28(16): 2006-2010.

16. T waves • T wave changes was the most common cause for continued investigation in the cohort • This is probably due to the non specific nature of this finding • Disqualifying findings were identified in 18.75% of evaluations in these subjects • Whether these clinical findings were associated with the ECG findings or were incidental is unclear

17. PRE EXCITATION PATTERN • Signs of pre-excitation were identified in 14 subjects who comprised 0.96% of the study population • This is a higher percentage than previously reported (0.2%) • Probably resulted from the high awareness to this condition among interpreting cardiologists • No cases of pre-excitation syndrome identified • This is similar to a previous report from the Israeli air force Ferrer MF. Electrocardiographic variations, arrhythmias, pacemakers. In: Lew EA, Gajewski J. Medical Risks: Trends in Mortality by age and time elapsed. New York, NY: Praeger 1990. Grossman A et al Use of adenosine test for the exclusion of pre-excitation syndrome in asymptomatic individuals. Ann Noninvasive Electrocardiol 2011 Apr 16 (2); 180-183.

18. LVH criteria • Signs of LVH were identified in only 7.56% of the study population • This is significantly lower than reported in previous studies (up to 45%) • This is surprising given the young age of the population and the fact that the subjects were all very physically active • Disqualifying findings were identified in 18.2% of these subjects Pelliccia A et al Prevalence of abnormal electrocardiograms in a large, unselected population undergoing pre-participation cardiovascular screening. Eur Heart J 2007; 28(16): 2006-2010

19. LIMITATIONS • A selective cohort (healthy, physically active underwent ECG during screening for athletic activity) • Single physician interpreting all ECGS (high inter-observer variability reported in the literature)

20. Conclusions • T wave changes, although non-specific, may be a sign of cardiac disease • Pre-excitation pattern is of low specificity for the diagnosis of PES, but because of the lethal potential of this condition, adenosine should be performed in subjects with a suspicious pattern

21. Conclusions • ECG-LVH criteria have a low sensitivity in young subjects, but because of the fatal potential of HOCM and because the specificity of the ECG is very high, echocardiography should be performed to all those with ECG criteria • Policy makers should take into account the large number of echocardiographies that will be performed in order to identify subjects with true LVH

22. Conclusions • Sinus bradycardia and conduction disturbances (low degree AVB and hemiblocks) probably result from increased vagal tone and require no additional work-up

23. Thank you