Electrocardiographic changes in 1000 highly trained junior elite athletes

Vectorcardiogram in athletes: The Sun Valley Ski Study

BACKGROUND

Global electrical heterogeneity (GEH) is associated with sudden cardiac death (SCD) in adults of 45 years and above. However, GEH has not been previously measured in young athletes. The goal of this study was to establish a reference for vectorcardiograpic (VCG) metrics in male and female athletes.

METHODS

Skiers (n = 140; mean age 19.2 ± 3.5 years; 66% male, 94% white; 53% professional athletes) were enrolled in a prospective cohort. Resting 12-lead ECGs were interpreted per the International ECG criteria. Associations of age, sex, and athletic performance with GEH were studied.

RESULTS

In age and training level-adjusted analyses, male sex was associated with a larger T vector [T peak magnitude +186 (95% CI 106-266) µV] and a wider spatial QRS-T angle [+28.2 (17.3-39.2)°] as compared to women. Spatial QRS-T angle in the ECG left ventricular hypertrophy (LVH) voltage group (n = 21; 15%) and normal ECG group did not differ (67.7 ± 25.0 vs. 66.8 ± 28.2; p = 0.914), suggesting that ECG LVH voltage in athletes reflects physiological remodeling. In contrast, skiers with right ventricular hypertrophy (RVH) voltage (n = 26, 18.6%) had wider QRS-T angle (92.7 ± 29.6 vs. 66.8 ± 28.2°; p = 0.001), larger SAI QRST (194.9 ± 30.2 vs. 157.8 ± 42.6 mV × ms; p < 0.0001), but similar peak SVG vector magnitude (1976 ± 548 vs. 1939 ± 395 µV; p = 0.775) as compared to the normal ECG group. Better athletic performance was associated with the narrower QRS-T angle. Each 10% worsening in an athlete's Federation Internationale de' Ski downhill ranking percentile was associated with an increase in spatial QRS-T angle by 2.1 (95% CI 0.3-3.9) degrees (p = 0.013).

CONCLUSION

Vectorcardiograpic adds nuances to ECG phenomena in athletes.

Optimal Running Dose and Cardiovascular Risk

The cardiovascular benefits of regular exercise are well established. A mortality benefit has clearly been demonstrated for those that participate in light and moderate exercise. Less is known regarding the long-term effects of vigorous regular running over an extended period. In recent years, myocardial fibrosis, arrhythmias, and coronary artery calcium have been demonstrated in high-intensity exercisers. However, the prognostic implication of these findings remains unknown, and thus, there is insufficient evidence, and potentially not a need, to recommend a maximal running dose or limit for healthy individuals who already train intensively. For those otherwise healthy individuals who wish to run for cardiovascular health benefits, following the standard guidelines of 150 min of moderate-intensity exercise or 75 min of vigorous exercise weekly is recommended. Prevention and screening remain as key to lowering morbidity and mortality in all individuals.

Utility of incomplete right bundle branch block as an isolated ECG finding in children undergoing initial cardiac evaluation

OBJECTIVE

This study evaluates the ability of experienced pediatric electrophysiologists (EPs) to reliably classify incomplete right bundle branch block (IRBBB) and assesses its clinical utility as an isolated ECG finding in a group of healthy outpatient children without prior cardiac evaluation.

DESIGN

We performed a retrospective analysis of all electrocardiographic and echocardiographic records at Boston Children's Hospital between January 1, 2005, and December 31, 2014. Echocardiographic diagnoses were identified if registered between the date of the index electrocardiogram and the ensuing year. A selected subset of 473 ECGs was subsequently reanalyzed in a blinded manner by six pediatric EPs to determine the consistency with which the finding of IRBBB could be assigned.

RESULTS

Of the 331 278 ECGs registered in the BCH database, 32 127 (9.7%) met inclusion criteria and were analyzed for the prevalence of isolated right bundle conduction disturbance findings. The mean age was 12.1 ± 4.0 years, and the population was 49% male. Of the 32 127 ECGs, 72.5% were coded normal, 3.0% were coded IRBBB, and 0.5% were coded complete right bundle branch block (CRBBB). A total of 7.3% of patients coded as normal had an ensuing echocardiogram, compared to 12.5% coded IRBBB. Echo findings were recorded in 0.1% of normal and 0.2% of IRBBB. Patients with ASD-secundum type were no more likely to have isolated IRBBB on previous ECG than the general population (2.5% vs 3.0%). Analysis of inter-reader variability in ECG findings and conduction disturbance identification was high (range of IRBBB prevalence 1-20% among readers). Reinterpretation of ECGs using explicit diagnostic criteria did not demonstrate consistent discrimination of IRBBB and Normal ECGs.

CONCLUSIONS

IRBBB is not uncommon in a healthy school age population and is observed to have high inter-reader variability. It was associated with increased use of echocardiographic exam but was not associated with increased rate of echocardiographic findings when compared with rates for normal ECGs.

Prevention of sudden cardiac death in athletes, sportspersons and marathoners in India

The annual incidence of sudden cardiac death (SCD) in athletes is significantly lower than the general population. However, when SCD occurs in an athlete during sporting event or training, it sends shockwaves in the society and raises questions about cardiovascular effects of sports and exercise. This document reviews the causes and mechanism of SCD in sports and exercise in young and older athletes. In the Indian context, we suggest a ‘pre-participation screening’ of young and older athletes and consider a ‘supervised, graded exercise regime’ for the uninitiated, older sports participant. Finally, the document proposes medical infrastructure required to successfully revive a victim of sudden cardiac arrest during a sporting event.

Pre- and post-exercise electrocardiogram pattern modifications in apparently healthy school adolescents in Cameroon

Background Physical Education and Sport (PES) is compulsory in Cameroonian education system. Cardiac accidents and sudden cardiac deaths (SCD) have been reported during PES examinations. This study aimed to contribute in the prevention of these cardiac accidents by studying pre- and post-exercise electrocardiogram (ECG) pattern modifications in apparently healthy school adolescents. Methods One hundred school adolescents without apparent heart disease [aged 18 ± 2 years; body mass index (BMI): 21.9 ± 2.3] were included. Participants performed two intermittent sprint-endurance tests. The test consisted in walking 2000 m as warm-up, followed by sprint and endurance races. A 12-leads ECG was performed before and in 5 min after the tests. ECG patterns changes were studied with particular attention to abnormalities that could be associated with risk of SCD. Results At rest, ECG patterns variants consisted of bradycardia (30%), sinus arrhythmia (9%), posterior hemi post-block (2%), and early repolarization (3%). which disappeared after exercise in all participants. QTc (ms) and heart rate (HR) increased after exercise (p < 0.001); and RR (ms) decreased post-exercise (p < 0.001). Other changes includes the appearance of the T-waves reversed in precordial leads (V2-V4) (p < 0.001), ventricular (6%), atrial and other supraventricular premature beats (2%) in the post-exercise ECG. Left ventricular hypertrophy (2%), right auricular enlargement (2%), short PR (2%) appeared at the end of the tests. Conclusion This study suggests that an intermittent exercise can induce cardiac abnormalities able to provoke cardiac accidents and SCD in apparently healthy school adolescents.

Impact of the dynamic and static component of the sport practised for electrocardiogram analysis in screening athletes

To interpret the electrocardiogram (ECG) of athletes, the recommendations of the ESC and the Seattle criteria define type 1 peculiarities, those induced by training, and type 2, those not induced by training, to rule out cardiomyopathy. The specificity of the screening was improved by Sheikh who defined "Refined Criteria," which includes a group of intermediate peculiarities. The aim of our study was to investigate the influence of static and dynamic components on the prevalence of different types of abnormalities. The ECGs of 1030 athletes performed during preparticipation screening were interpreted using these three classifications. Our work revealed 62/16%, 69/13%, and 71/7% of type 1 peculiarities and type 2 abnormalities for the ESC, Seattle, and Refined Criteria algorithms, respectively(P<.001). For type 2 abnormalities, three independent factors were found for the ESC and Seattle criteria: age, Afro-Caribbean origin, and the dynamic component with, for the latter, an OR[95% CI] of 2.35[1.28-4.33] (P=.006) and 1.90[1.03-3.51] (P=.041), respectively. In contrast, only the Afro-Caribbean origin was associated with type 2 abnormalities using the Refined Criteria: OR[95% CI] 2.67[1.60-4.46] (P<.0001). The Refined Criteria classified more athletes in the type 1 category and fewer in the type 2 category compared with the ESC and Seattle algorithms. Contrary to previous studies, a high dynamic component was not associated with type 2 abnormalities when the Refined Criteria were used; only the Afro-Caribbean origin remained associated. Further research is necessary to better understand adaptations with regard to duration and thus improve the modern criteria for ECG screening in athletes.

International Recommendations for Electrocardiographic Interpretation in Athletes

Sudden cardiac death (SCD) is the leading cause of mortality in athletes during sport. A variety of mostly hereditary, structural, or electrical cardiac disorders are associated with SCD in young athletes, the majority of which can be identified or suggested by abnormalities on a resting 12-lead electrocardiogram (ECG). Whether used for diagnostic or screening purposes, physicians responsible for the cardiovascular care of athletes should be knowledgeable and competent in ECG interpretation in athletes. However, in most countries a shortage of physician expertise limits wider application of the ECG in the care of the athlete. A critical need exists for physician education in modern ECG interpretation that distinguishes normal physiological adaptations in athletes from distinctly abnormal findings suggestive of underlying pathology. Since the original 2010 European Society of Cardiology recommendations for ECG interpretation in athletes, ECG standards have evolved quickly over the last decade; pushed by a growing body of scientific data that both tests proposed criteria sets and establishes new evidence to guide refinements. On February 26-27, 2015, an international group of experts in sports cardiology, inherited cardiac disease, and sports medicine convened in Seattle, Washington, to update contemporary standards for ECG interpretation in athletes. The objective of the meeting was to define and revise ECG interpretation standards based on new and emerging research and to develop a clear guide to the proper evaluation of ECG abnormalities in athletes. This statement represents an international consensus for ECG interpretation in athletes and provides expert opinion-based recommendations linking specific ECG abnormalities and the secondary evaluation for conditions associated with SCD.

Comparison of Electrocardiographic Criteria for Identifying Left Ventricular Hypertrophy in Athletes from Different Sports Modalities

OBJECTIVES:

In athletes, isolated electrocardiogram high voltage criteria are widely used to evaluate left ventricular hypertrophy, but positive findings are thought to represent normal electrocardiogram alterations. However, which electrocardiogram criterion can best detect left ventricular hypertrophy in athletes of various sport modalities remains unknown.

METHODS:

Five electrocardiogram criteria used to detect left ventricular hypertrophy were tested in 180 male athletes grouped according to their sport modality: 67% low-static and high-dynamic components and 33% high-static and high-dynamic components of exercise. The following echocardiogram parameters are the gold standard for diagnosing left ventricular hypertrophy: left ventricular mass index ≥134 g.m-2, relative wall thickness ≥0.42 mm, left ventricular diastolic diameter index ≥32 mm.m-2, septum wall thickness ≥13 mm, and posterior wall thickness ≥13 mm. Results for the various criteria were compared using the kappa coefficient. Significance was established at p<0.05.

RESULTS:

Fifty athletes (28%) presented with left ventricular hypertrophy according to electrocardiogram findings, with the following sensitivities and specificities, respectively: 38-53% and 79-83% (Perugia), 22-40% and 89-91% (Cornell), 24-29% and 90% (Romhilt-Estes), 68-87% and 20-23% (Sokolow-Lyon), and 0% and 99% (Gubner). The Perugia and Cornell criteria had higher negative predictive values for the low-static and high-dynamic subgroup. Kappa coefficients were higher for Romhilt-Estes, Cornell and Perugia criteria than for Sokolow-Lyon and Gubner criteria.

CONCLUSION:

All five evaluated criteria are inadequate for detecting left ventricular hypertrophy, but the Perugia, Cornell and Romhilt-Estes criteria are useful for excluding its presence. The Perugia and Cornell criteria were more effective at excluding left ventricular hypertrophy in athletes involved in a sport modality with low-static and high-dynamic component predominance.

A comparison of Cornell and Sokolow-Lyon electrocardiographic criteria for left ventricular hypertrophy in a military male population in Taiwan: the Cardiorespiratory fitness and HospItalization Events in armed Forces study

BACKGROUND

The Cornell and Sokolow-Lyon electrocardiography (ECG) criteria have been widely used for diagnosing left ventricular hypertrophy (LVH) in patients with hypertension. However, the correlations of these ECG criteria with LVH were rarely compared in military members who received rigorous training, particularly of the Asian male population.

METHODS

We compared the Cornell voltage and product criteria with the Sokolow-Lyon criteria for the echocardiographic LVH in 539 military male members, ages 18-50 years and free of hypertension in the Cardiorespiratory fitness and HospItalization Events in armed Forces (CHIEF) study in Taiwan. Pearson's correlation coefficient was used to determine the association of each ECG criterion with the index of left ventricular mass (LVM, g)/height (m)^2.7. The sensitivities and specificities were estimated using a receiver-operating characteristics (ROC) curve in relation to the echocardiographic LVH which was defined as LVM index ≥49 g/m^2.7.

RESULTS

The correlations of the Cornell voltage and product criteria (r=0.24 and 0.26 respectively, both P<0.0001) were stronger than that of the Sokolow-Lyon criteria (r=0.049 and 0.095, and P=0.26 and 0.03 respectively) with the LVM index. Similarly the performances of the Cornell voltage and product criteria for the echocardiographic LVH [area under curve (AUC): 0.66 and 0.68, both P<0.0001] were superior to that of the Sokolow-Lyon criteria (AUC: 0.54 and 0.53, both P>0.1) in the area under the ROC curve analysis.

CONCLUSIONS

The Cornell ECG criteria for the echocardiographic LVH had better performance than the Sokolow-Lyon criteria in a young military male cohort in Taiwan.

Electrical and structural adaptations of the paediatric athlete’s heart: a systematic review with meta-analysis

Aim

To describe the electrocardiographic (ECG) and echocardiographic manifestations of the paediatric athlete’s heart, and examine the impact of age, race and sex on cardiac remodelling responses to competitive sport.

Design

Systematic review with meta-analysis.

Data sources

Six electronic databases were searched to May 2016: MEDLINE, PubMed, EMBASE, Web of Science, CINAHL and SPORTDiscus.

Inclusion criteria

(1) Male and/or female competitive athletes, (2) participants aged 6–18 years, (3) original research article published in English language.

Results

Data from 14 278 athletes and 1668 non-athletes were included for qualitative (43 articles) and quantitative synthesis (40 articles). Paediatric athletes demonstrated a greater prevalence of training-related and training-unrelated ECG changes than non-athletes. Athletes ≥14 years were 15.8 times more likely to have inferolateral T-wave inversion than athletes <14 years. Paediatric black athletes had significantly more training-related and training-unrelated ECG changes than Caucasian athletes. Age was a positive predictor of left ventricular (LV) internal diameter during diastole, interventricular septum thickness during diastole, relative wall thickness and LV mass. When age was accounted for, these parameters remained significantly larger in athletes than non-athletes. Paediatric black athletes presented larger posterior wall thickness during diastole (PWTd) than Caucasian athletes. Paediatric male athletes also presented larger PWTd than females.

Conclusions

The paediatric athlete’s heart undergoes significant remodelling both before and during ‘maturational years’. Paediatric athletes have a greater prevalence of training related and training-unrelated ECG changes than non-athletes, with age, race and sex mediating factors on cardiac electrical and LV structural remodelling.

International criteria for electrocardiographic interpretation in athletes: Consensus statement

Sudden cardiac death (SCD) is the leading cause of mortality in athletes during sport. A variety of mostly hereditary, structural or electrical cardiac disorders are associated with SCD in young athletes, the majority of which can be identified or suggested by abnormalities on a resting 12-lead electrocardiogram (ECG). Whether used for diagnostic or screening purposes, physicians responsible for the cardiovascular care of athletes should be knowledgeable and competent in ECG interpretation in athletes. However, in most countries a shortage of physician expertise limits wider application of the ECG in the care of the athlete. A critical need exists for physician education in modern ECG interpretation that distinguishes normal physiological adaptations in athletes from distinctly abnormal findings suggestive of underlying pathology. Since the original 2010 European Society of Cardiology recommendations for ECG interpretation in athletes, ECG standards have evolved quickly, advanced by a growing body of scientific data and investigations that both examine proposed criteria sets and establish new evidence to guide refinements. On 26-27 February 2015, an international group of experts in sports cardiology, inherited cardiac disease, and sports medicine convened in Seattle, Washington (USA), to update contemporary standards for ECG interpretation in athletes. The objective of the meeting was to define and revise ECG interpretation standards based on new and emerging research and to develop a clear guide to the proper evaluation of ECG abnormalities in athletes. This statement represents an international consensus for ECG interpretation in athletes and provides expert opinion-based recommendations linking specific ECG abnormalities and the secondary evaluation for conditions associated with SCD.

Electrocardiographic Changes Induced by Endurance Training and Pubertal Development in Male Children

Training-induced electrocardiographic changes are common in adult athletes. However, a few data are available on electrocardiogram (ECG) in preadolescent athletes and little is known about the potential changes induced by training on 12-lead electrocardiogram (ECG) at rest. Twelve-lead ECGs at rest and complete echocardiographic examinations were performed in 94 children (57 endurance athletes, 37 sedentary controls; mean age 10.8 ± 0.2 and 10.2 ± 0.2 years, respectively) at baseline and after 5 months of growth and training in athletes and of natural growth in controls. At baseline, athletes had lower heart rate at rest compared with controls (p = 0.046) and a further decrease was observed after training (p <0.0001). An incomplete right bundle branch block was found in 19% of athletes and 15% of controls (p = 0.69) with no changes after training. Although none of the athletes showed negative T waves from V1 to V3, 6% of controls at baseline had T-wave inversion V1 to V3 with a decrease to 3% after 5 months (p = 0.16). The early repolarization pattern did not differ between athletes and controls and was correlated with Tanner's scale score in the overall population both at first and second evaluation (R = 0.30, R = 0.27, p = 0.005, p = 0.012, respectively). No correlations were found between ECG and echocardiographic data. In conclusion, 12-lead ECG at rest is not substantially affected by training in children, despite a physiological increase in cavity size. Thus, in preadolescent athletes, 12-lead ECG at rest does not reflect exercise-induced morphologic remodeling and seems to be influenced more by sexual maturation than by training.

Correlation between ECG changes and early left ventricular remodeling in preadolescent footballers

The aim of this study was to assess the early electrocardiogram (ECG) changes induced by physical training in preadolescent elite footballers. This study included 94 preadolescent highly trained male footballers (FG) competing in Serbian Football League (minimum of 7 training hours/week) and 47 age-matched healthy male controls (less than 2 training hours/week) (CG). They were screened by ECG and echocardiography at a tertiary referral cardio center. Sokolow-Lyon index was used as a voltage electrocardiographic criterion for left ventricular hypertrophy diagnosis. Characteristic ECG intervals and voltage were compared and reference range was given for preadolescent footballers. Highly significant differences between FG and CG were registered in all ECG parameters: P-wave voltage (p < 0.001), S-wave (V1 or V2 lead) voltage (p < 0.001), R-wave (V5 and V6 lead) voltage (p < 0.001), ECG sum of S V_1-2 + R V_5-6 (p < 0.001), T-wave voltage (p < 0.001), QRS complex duration (p < 0.001), T-wave duration (p < 0.001), QTc interval duration (p < 0.001), and R/T ratio (p < 0.001). No differences were found in PQ interval duration between these two groups (p > 0.05). During 6-year follow-up period, there was no adverse cardiac event in these footballers. None of them expressed pathological ECG changes. Benign ECG changes are presented in the early stage of athlete's heart remodeling, but they are not related to pathological ECG changes and they should be regarded as ECG pattern of LV remodeling.

Electrocardiographic abnormalities in elite high school athletes: comparison to adolescent hypertrophic cardiomyopathy

BACKGROUND

In athletes, ECG changes from physiological cardiac remodelling are common but can overlap with findings from a pathological disorder. We compared ECG findings in a group of elite high school athletes to a cohort of adolescents with hypertrophic cardiomyopathy (HCM).

METHODS/RESULTS

We prospectively performed 15-lead ECGs and echocardiograms in 147 elite high school athletes. Student-athlete ECGs were compared in blinded fashion to ECGs of 148 adolescents with HCM of similar age and ethnicity. Standard ECG hypertrophy criteria and established expert opinion guidelines (European Society of Cardiology, ESC and Seattle criteria) were analysed. All student-athletes had normal echocardiograms. Overall, 77/147 (52%) of student-athletes met standard ECG criteria for ventricular hypertrophy compared to 126/148 (85%) adolescents with HCM (p<0.0001). There were 112/148 (76%) adolescents with HCM who had pathological Q-waves, T-wave inversion and/or ST-segment depression compared to 1/147 (1%) athletes (p<0.0001). Most patients with HCM (84%, 124/148) had ≥1 abnormal ECG finding(s) according to Seattle criteria, compared to 1% of student-athletes (2/147). Similarly, 130/148 (88%) patients with HCM met group-2 ESC criteria (abnormal), compared to 36/147 (24%) student-athletes (p<0.0001).

CONCLUSIONS

Over 50% of elite high school athletes with echocardiographically confirmed normal hearts satisfied standard voltage criteria for ventricular hypertrophy. Pathological Q-waves, T-wave inversion or ST-segment depression were most helpful in distinguishing adolescents with HCM from normals. Both ESC and Seattle criteria successfully stratified the student-athlete and HCM cohorts, however each had a false-negative rate >10% for the HCM cohort. The Seattle criteria demonstrated a significantly lower false-positive rate (1%) than the ESC criteria (24%).

Recommendations for participation in leisure-time physical activity and competitive sports in patients with arrhythmias and potentially arrhythmogenic conditions Part I: Supraventricular arrhythmias and pacemakers

This document by the Study Group on Sports Cardiology of the European Society of Cardiology extends on previous recommendations for sports participation for competitive athletes by also incorporating guidelines for those who want to perform recreational physical activity. For different supraventricular arrhythmias and arrhythmogenic conditions, a description of the relationship between the condition and physical activity is given, stressing how arrhythmias can be influenced by exertion or can be a reflection of the (patho)physiological cardiac adaptation to sports participation itself. The following topics are covered in this text: sinus bradycardia; atrioventricular nodal conduction disturbances; pacemakers; atrial premature beats; paroxysmal supraventricular tachycardia without pre-excitation; pre-excitation, asymptomatic or with associated arrhythmias (i.e. Wolff-Parkinson-White syndrome); atrial fibrillation; and atrial flutter. A related document discusses ventricular arrhythmias, channelopathies and implantable cardioverter defibrillators.

Using the 12-Lead Electrocardiogram in the Care of Athletic Patients

This article summarizes the role of the 12-lead electrocardiogram (ECG) for the clinical care of athletes, with particular reference to the influence of age, gender, ethnicity, and type of sport on the appearance of the ECG, and its role in differentiating physiologic exercise-related changes from pathologic conditions implicated in sudden cardiac death (SCD). The article also explores the potential role of the ECG in detecting athletes at risk of SCD. In addition, the article reviews the evolution of ECG interpretation criteria and emphasizes the limitations of the ECG as well as the potential for future research.

Differences in the electrocardiographic QT interval of various breeds of athletic horses during rest and exercise

OBJECTIVES

Quantitative measurements of cardiac repolarization, defined as the electrocardiographic QT interval, have important diagnostic implications in humans, as irregularities can trigger potentially fatal ventricular tachyarrhythmia. In both humans and horses, cardiac repolarization is influenced to some extent by heart rate, age, body weight (BW), sex, autonomic tone, and environment. In horses, there is substantial inter-breed variation in size and training, and the aims of this study were therefore to determine the best model describing the QT to RR relationship in breeds of various athletic horses and to test for differences in the QT interval.

ANIMALS

Ten Icelandic horses, 10 Arabian horses, 10 Thoroughbreds, 10 Standardbreds, six Coldblood trotters, 10 Warmbloods (dressage) and 10 Warmbloods (show jumping). All horses were geldings.

METHODS

QT intervals were measured from resting to peak exercise level and plotted against RR intervals. Data points were fitted with relevant regression models, and the effect of breed, BW, and estimated exercise intensity was examined.

RESULTS

For all breeds in this study, the QT interval was best described as a function of RR by the piecewise linear regression model. The breed of horse had a significant effect on the model. There was no systematic effect of BW or estimated exercise intensity, but a high inter-horse variability was observed.

CONCLUSIONS

The equine QT interval should preferably be corrected for heart rate according to breed. In addition, the results indicate that equine studies of the QT interval must be designed to eliminate the influence of a large inter-horse variation.

Screening of athletes: An electrocardiogram is not enough

Professional and amateur athletic training can cause tremendous overload of the cardiovascular system and thus become a trigger of serious and often fatal cardiac events in athletes with a previously undetected underlying cardiovascular disease. Therefore, every athlete should undergo a specialized diagnostic and qualification screening before a training program is prescribed or continued. However, it is still an unresolved issue which of the accessible diagnostic tools should be routinely applied in order to increase the safety of extreme physical training and reduce the risk of sudden cardiac death. Pre-participation athlete evaluation including a standard electrocardiogram (ECG), physical examination, and familial history of cardiovascular diseases is important, but does not always guarantee high diagnostic accuracy. Hence, the aim of this review article is to discuss the controversy over the usefulness of ECG for the detection of cardiovascular diseases in athletes as well as the views on athlete screening methods in Europe and the USA. Differential diagnostic options and screening schemes are also described in particular groups of athletes in reference to their age, cardiovascular risk factors, as well as intensity and type of sport discipline.

The Acute Risks of Exercise in Apparently Healthy Adults and Relevance for Prevention of Cardiovascular Events

BACKGROUND

Increased physical activity (PA) is associated with improved quality of life and reductions in cardiovascular (CV) morbidity and all-cause mortality in the general population in a dose-response manner. However, PA acutely increases the risk of adverse CV event or sudden cardiac death (SCD) above levels expected at rest. We review the likelihood of adverse CV events related to exercise in apparently healthy adults and strategies for prevention, and contextualize our understanding of the long-term risk reduction conferred from PA.

METHODS

A systematic review of the literature was performed using electronic databases; additional hand-picked relevant articles from reference lists and additional sources were included after the search.

RESULTS

The incidence of adverse CV events in adults is extremely low during and immediately after PA of varying types and intensities and is significantly lower in those with long-standing PA experience. The risk of SCD and nonfatal events during and immediately after PA remains extremely low (well below 0.01 per 10,000 participant hours); increasing age and PA intensity are associated with greater risk. In most cases of exercise-related SCD, occult CV disease is present and SCD is typically the first clinical event.

CONCLUSIONS

Exercise acutely increases the risk of adverse CV events, with greater risk associated with vigorous intensity. The risks of an adverse CV event during and immediately after exercise are outweighed by the health benefits of vigorous exercise performed regularly. A key challenge remains the identification of occult structural heart disease and inheritable conditions that increase the chances of lethal arrhythmias during exercise.

The Impending Dilemma of Electrocardiogram Screening in Athletic Children

Sudden cardiac death (SCD) affects 2/100,000 young, active athletes per year of which 40% are less than 18 years old. In 2004, the International Olympic Committee accepted the Lausanne Recommendations, including a 12-lead electrocardiogram (ECG), as a pre-participation screening tool for adult Olympic athletes. The debate on extending those recommendations to the pediatric population has recently begun. The aims of our study were to highlight the characteristics of the young athlete ECG, phenotypical manifestations of SCD-related disease in children, and challenges of implanting ECG screening in athletic children. A systematic review of the literature is performed. We searched available electronic medical databases for articles relevant to SCD, ECG, silent cardiac diseases, and athletic children. We focused on ECG screening and description in a pediatric population. We identified 2240 studies. Sixty-two relevant articles and one book were selected. In children, prepubertal ECG and the ECG phenotype of most SCD-related diseases differ notably from adults. The characteristics of the prepubertal ECG and of the phenotypical manifestation of SCD-related disease in children will result in less specific and less sensitive ECG-based screening programs. Those limitations advise against extending the adult recommendation to children, without further studies. Until then, history and physical exam should remain the cornerstone of screening for SCD-related pathologies in children.

Impact of specific training and competition on myocardial structure and function in different age ranges of male handball players

Handball activity involves cardiac changes and demands a mixture of both eccentric and concentric remodeling within the heart. This study seeks to explore heart performance and cardiac remodeling likely to define cardiac parameters which influence specific performance in male handball players across different age ranges. Forty three players, with a regular training and competitive background in handball separated into three groups aged on average 11.78±0.41 for youth players aka “schools”, “elite juniors” 15.99±0.81 and “elite adults” 24.46±2.63 years, underwent echocardiography and ECG examinations. Incremental ergocycle and specific field (SFT) tests have also been conducted. With age and regular training and competition, myocardial remodeling in different age ranges exhibit significant differences in dilatation’s parameters between “schools” and “juniors” players, such as the end-diastolic diameter (LVEDD) and the end-systolic diameter of the left ventricle (LVESD), the root of aorta (Ao) and left atrial (LA), while significant increase is observed between “juniors” and “adults” players in the interventricular septum (IVS), the posterior wall thicknesses (PWT) and LV mass index. ECG changes are also noted but NS differences were observed in studied parameters. For incremental maximal test, players demonstrate a significant increase in duration and total work between “schools” and “juniors” and, in total work only, between “juniors” and “seniors”. The SFT shows improvement in performance which ranged between 26.17±1.83 sec to 31.23±2.34 sec respectively from “seniors” to “schools”. The cross-sectional approach used to compare groups with prior hypothesis that there would be differences in exercise performance and cardiac parameters depending on duration of prior handball practice, leads to point out the early cardiac remodeling within the heart as adaptive change. Prevalence of cardiac chamber dilation with less hypertrophy remodeling was found from “schools” to “juniors” while a prevalence of cardiac hypertrophy with less pronounced chamber dilation remodeling was noted later.

"Persistent Juvenile" T-Wave Pattern May Not Be Persistent: Case Series and Literature Review

BACKGROUND

T-wave inversions (TWI) can signify serious pathology, but may also represent a benign variant. One such variant has been termed the "persistent juvenile" T-wave pattern (PJTWP). It is characterized by TWI in the right precordium, and has been understood to represent an arrested stage of the normal electrocardiographic evolution from childhood.

CASE REPORT

A series of four African-American (AA) women, ages 20 to 43 years, presented to the Emergency Department, and were found to have right precordial TWI that was absent on prior electrocardiograms. The diagnostic evaluation did not reveal acute cardiopulmonary causes for these new TWIs. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: The "persistent" juvenile pattern may not be actually persistent in the individual patient. In an appropriate patient, such as a young AA woman, where acute cardiopulmonary disease has been reasonably ruled out, the finding of new right precordial TWI should not preclude the diagnosis of PJTWP.

The prevalence of abnormal ECG in trained sportsmen

BACKGROUND

Competitive sports training causes structural and conductive system changes manifesting by various electrocardiographic alterations. We undertook this study to assess the prevalence of abnormal ECG in trained Indian athletes and correlate it with the nature of sports training, that is endurance or strength training.

METHODS

We evaluated a standard resting, lying 12 lead Electrocardiogram (ECG) in 66 actively training Indian athletes. Standard diagnostic criteria were used to define various morphological ECG abnormalities.

RESULTS

33/66 (50%) of the athletes were undertaking endurance training while the other 33 (50%) were involved in a strength-training regimen. Overall 54/66 (81%) sportsmen had significant ECG changes. 68% of these changes were considered as normal training related features, while the remaining 32% were considered abnormal. There were seven common training related ECG changes-Sinus Bradycardia (21%), Sinus Arrhythmia (16%), 1st degree Atrioventricular Heart Block (6%), Type 1 2nd-degree Atrioventicular Heart Block (3%), Incomplete Right bundle branch block (RBBB) (24%), Early Repolarization (42%), Left Ventricular Hypertrophy (LVH) (14%); while three abnormal ECG changes--T-wave inversion (13%), RBBB(4%), Right ventricular hypertrophy (RVH) with strain (29%) were noted. Early repolarization (commonest change), sinus bradycardia, and incomplete RBBB were the commoner features noticed, with a significantly higher presence in the endurance trained athletes.

CONCLUSION

A high proportion of athletes undergoing competitive level sports training are likely to have abnormal ECG recordings. Majority of these are benign, and related to the physiological adaptation to the extreme levels of exertion. These changes are commoner during endurance training (running) than strength training (weightlifting).

National Athletic Trainers' Association position statement: Preparticipation physical examinations and disqualifying conditions

OBJECTIVE

To present athletic trainers with recommendations for the content and administration of the preparticipation physical examination (PPE) as well as considerations for determining safe participation in sports and identifying disqualifying conditions.

BACKGROUND

Preparticipation physical examinations have been used routinely for nearly 40 years. However, considerable debate exists as to their efficacy due to the lack of standardization in the process and the lack of conformity in the information that is gathered. With the continuing rise in sports participation at all levels and the growing number of reported cases of sudden death in organized athletics, the sports medicine community should consider adopting a standardized process for conducting the PPE to protect all parties.

RECOMMENDATIONS

Recommendations are provided to equip the sports medicine community with the tools necessary to conduct the PPE as effectively and efficiently as possible using available scientific evidence and best practices. In addition, the recommendations will help clinicians identify those conditions that may threaten the health and safety of participants in organized sports, may require further evaluation and intervention, or may result in potential disqualification.

Normal Variant T-Wave Changes in an Athlete with Structurally Normal Cardiac Anatomy and Function

Athletes who perform regular and intensive physical activity may undergo structural and electrical remodeling of the heart that results in electrocardiographic changes that can cause concern. Marked T-wave inversion may represent one such physiologic change. On the other hand, T-wave inversion could be a sign of inherited heart muscle disease or may be a normal variant. Therefore, it is imperative to determine whether abnormalities on an athlete's electrocardiography (ECG) reflect underlying cardiac disease that could place the athlete at risk for sudden cardiac death. For athletes who present with markedly abnormal ECGs, the echocardiography and cardiac magnetic resonance imaging should be considered to evaluate the potential for cardiac disease. We report the case of a high-intensity athlete with concerning ECG changes who required additional studies to exclude cardiac disease.

The Impact of Sports Cardiology on the Practice of Primary Care Sports Medicine: Where Were We, Where Are We, Where Are We Headed?

This article is a commentary on the role of sports cardiologists in the athletic arena and the beneficial impact they offer sports medicine in the comprehensive care of competitive athletes. The focus is a dialogue on current recommendations for primary prevention of sudden cardiac arrest (SCA), incorporating elements of the preparticipation evaluation and continuing care of athletes with diagnosed heart disease (HD). The feasibility and potential advantages of implementing well-designed preparticipation cardiovascular screening programs and the role of sports cardiologists to educate primary care team physicians on secondary prevention of SCA and proper treatment of underlying HD are discussed.

The U-shaped relationship between exercise and cardiac morbidity

Exercise confers a plethora of health benefits that are well documented, whereas physical inactivity is a leading risk factor for cardiovascular morbidity and mortality. The dose of physical activity required to achieve these benefits is relatively modest and equates to jogging at a pace of 15min per mile for 20-30min daily. In the current era, most athletes engage in a volume and intensity of exercise that is at least 5-10-fold greater than the general recommendations for physical activity. Such practice is evidenced by the fact that many sportsmen have achieved athletic feats that were considered impossible only 2 decades ago. Numerous studies in retired athletes have consistently shown a reduced incidence of heart disease and an increased longevity of life. Occasionally, however, intense exercise is associated with sudden deaths in athletes harboring quiescent yet potentially sinister cardiac diseases. Despite the visibility afforded by such catastrophes, the reputation of exercise remains unscathed because most deaths can be accounted for by an underlying cardiac abnormality where exercise is a mere trigger for a fatal arrhythmia rather than the actual cause of death. More recently, there have been an emerging number of reports suggesting that intense exercise may have an adverse impact on an otherwise normal heart. This article will review the morbidity and mortality associated with sport and pose the question whether one can have "too much of a good thing."

T wave inversions in athletes: a variety of scenarios

Athletic intensive exercise is associated with repolarization changes affecting the ST-segment and T-wave morphology. The prevalence and distribution of these alterations are influenced by several demographic factors. One of the most challenging conundrums for both the cardiologist and the sports medicine physician is the correct interpretation of these repolarization changes to prevent an erroneous diagnosis with potentially serious consequences. A 12-lead electrocardiogram (ECG) demonstrating inverted T-waves may represent the first and only sign of such inherited heart muscle diseases, and may precede the detection of any structural changes in the heart, however, T-wave inversion in leads V1-V4 in black athletes may represent ethnic variation which is exaggerated by exercise.

The Validity of Adding ECG to the Preparticipation Screening of Athletes An Evidence Based Literature Review

OBJECTIVE

To review the available evidence establishing the validity of adding electrocardiogram to the preparticipation cardiac screening in athletes.

DATA SOURCES

MEDLINE and CINAHL databases were searched. Additional references from the bibliographies of retrieved articles were also reviewed and experts in the area were contacted.

SELECTION CRITERIA

Only original research articles seeking to establish the use of electrocardiography followed by second line investigations in athletes under 36 years of age were reviewed.

SEARCH RESULT AND QUALITY ASSESSMENT

The initial literature search identified 226 papers. Of these, 16 original articles (all type II evidence-population-based clinical studies) met the selection criteria and directly related to the use of electrocardiography in athletes cardiac screening. The methodological qualities of included studies were assessed using the Downs and Black checklist.

CONCLUSION

Screening with electrocardiography represents best clinical practice to prevent or reduce the risk of sudden cardiac death in athletes. It significantly improves the sensitivity of history and physical examination alone; it has reasonable specificity and excellent negative predictive value; and it is cost-effective. Future studies must be large, multicentre, multination, prospective trials powered to determine how different screening options affect the incidence of sudden cardiac death. Efforts should also be targeted toward secondary prevention of sudden cardiac death with pitch side cardiac resuscitation and the immediate use of defibrillator.

T-wave reversion in pediatric patients during exercise stress testing

OBJECTIVE

T-wave inversion in lateral electrocardiogram (ECG) leads (II, III, aVF, V4 -V6 ) is suspicious of cardiac pathology in pediatric patients, though many are found to have structurally normal hearts. The purpose of this study is to evaluate T-wave response during exercise stress testing (EST) in pediatric patients with structurally normal hearts and lateral-lead T-wave inversion on resting ECG.

DESIGN

An IRB-approved, retrospective review of EST databases at two centers identified patients with lateral-lead T-wave inversion on resting ECG. Inclusion criteria were normal exam and echocardiogram, absence of anginal chest pain, and age <18 years. All patients underwent treadmill or cycle ergometer EST. Data recorded included demographics, echocardiogram results, baseline ECG, EST method, peak heart rate and metabolic equivalents (METs), and heart rate and METs at T-wave reversion. T-wave reversion was considered complete if T-waves reverted in all leads, partial if reversion occurred in only some leads, and none if no reversion occurred.

RESULTS

The search identified 14 patients: nine females and five males (10 Caucasians and four African Americans) and an average age of 16 (range 12-18) years. Complete T-wave reversion occurred in 11 (79%) patients, partial in two (14%), and none in one (7%). Reversion occurred in both genders, ethnicities, and EST methods. No complications occurred during EST; no adverse outcomes occurred during 2-year follow-up.

CONCLUSIONS

EST in pediatric patients with lateral-lead T-wave inversion on resting ECG and structurally and functionally normal hearts resulted in either complete or partial T-wave reversion in the vast majority of patients.