Evolving interpretation of the athlete's electrocardiogram: From European Society of Cardiology and Stanford criteria, to Seattle criteria and beyond

Prevalence and determinants of low QRS voltages and QRS fragmentation in children and adolescents undergoing sports pre-participation screening

AIMS

Low QRS voltages (LQRSV) in limb leads and QRS fragmentation (FQRS) are possible electrocardiographic signs of myocardial fibrosis and cardiomyopathy, but they are not listed in current criteria for interpreting athlete's electrocardiogram (ECG). We investigated the prevalence and determinants of LQRSV and FQRS in a cohort of young apparently healthy athletes undergoing pre-participation screening (PPS).

METHODS AND RESULTS

We analysed a consecutive series of 2140 ECG obtained during PPS of young athletes (mean age 12.5 ± 2.6 years, 7-18-year-old, 49% males). The peak-to-peak QRS voltage was measured in all limb leads, and LQRSV were defined when maximum value was <0.5 mV. Fragmented QRS morphologies were grouped into five patterns. Lead aVR was not considered. Maximum peak-to-peak QRS voltage in limb leads was 1.4 ± 0.4 mV, similar between younger and older athletes, but significantly lower in females than males (1.35 ± 0.38 mV vs. 1.45 ± 0.42 mV; P < 0.001). There was a weak correlation between maximal QRS voltages and body mass index (BMI), but not with type of sport or training load. Only five (0.2%) individuals showed LQRSV. At least one fragmented QRS complex was identified in 831 (39%) individuals but excluding the rSr' pattern in V1-V2, only 10 (0.5%) showed FQRS in ≥2 contiguous leads. They were older than those without FQRS, but did not differ in terms of gender, BMI, type of sport, or training load.

CONCLUSION

Low QRS voltages in limb leads and FQRS in ≥2 contiguous leads excluding V1-V2 are rare in young apparently healthy athletes and are not related to the type and intensity of sport activity. Therefore, they may require additional testing to rule out an underlying disease particularly when other abnormalities are present.

Comparison of four electrocardiographic criteria for the detection of cardiac abnormalities in Singapore athletes

Introduction

Sudden cardiac death in athletes is a rare occurrence, the most common cause being hypertrophic cardiomyopathy, which increases the risk of sustained ventricular tachycardia or ventricular fibrillation. Most of these young athletes are asymptomatic prior to the cardiac arrest. Several electrocardiogram criteria such as the European Society of Cardiology group 2 Criteria changes, Seattle Criteria, Refined Criteria, and most recently the 2017 International Criteria, have sought to improve the accuracy of identifying these at-risk athletes during pre-participation screening while minimising unnecessary investigations for the majority of athletes at low risk.We aimed to compare the above four criteria in our Singapore athlete population to identify which criterion performed the best in detecting cardiac abnormalities on echocardiography.

Method

Out of 1,515 athletes included in Changi General Hospital, Singapore registry between June 2007 and June 2014, the electrocardiograms of 270 athletes with further cardiac investigations were analysed. We compared the above four electrocardiographic criteria to evaluate which performed best for detecting cardiac abnormalities on echocardiography in our Southeast Asian athlete population.

Results

The European Society of Cardiology, Seattle, Refined and 2017 International Criteria had a sensitivity of 20%, 0%, 20% and 5%, respectively; a specificity of 64%, 93%, 84% and 97%, respectively; a positive predictive value of 4%, 0%, 9% and 11%, respectively; and a negative predictive value of 91%, 92%, 93% and 93%, respectively for detecting abnormalities on echocardiography.

Conclusion

The latest 2017 International Criteria performed the best as it had the highest specificity and positive predictive value, joint highest negative predictive value, and lowest false positive rate.

Criteria for interpretation of the athlete's ECG: A critical appraisal

The electrocardiogram (ECG) is cheap and widely available but its use as a screening tool for early identification of athletes with a cardiac disease at risk of sudden cardiac death is controversial because of presumed low specificity. In the last decade, several efforts have been made to improve the distinction between physiological and pathological ECG findings in the athlete, leading to continuous evolution of the interpretation criteria. The most recent 2017 International criteria grouped ECG changes into three categories: normal, borderline, and abnormal. Borderline findings warrant further investigations only when two or more are present while abnormal changes should always be considered as the sign of a possible underlying disease. This review encompasses the evolution of the athlete's ECG interpretation criteria and highlights areas of uncertainty that will need to be addressed by further studies.

The evaluation of adolescent chest pain: a screening ECG or PSC-17?

PURPOSE OF REVIEW

The present review offers an update on entities presenting as chest pain in the adolescent population. It discusses recently proposed tools and shared mental models used in primary and urgent care settings to evaluate chest pain, and their focus on identifying life-threatening processes. We consider whether the current practice may be improved by accounting for the increasingly recognized non-life-threatening causes of adolescent chest pain.

RECENT FINDINGS

The present experiences and behaviors of adolescents have added new causes of chest pain to the work-up of this disquieting chief complaint. The initial approach to adolescent chest pain has classically focused on ruling out life-threatening entities, and current diagnostic algorithms offer systematic approaches with similar emphases. A growing body of literature on the nonlife-threatening causes of adolescent chest pain, often categorized as idiopathic, suggests a need to reevaluate our practice.

SUMMARY

Adolescent chest pain is most often noncardiac and non-life threatening in nature, yet current diagnostic algorithms and evaluations emphasize identifying the exceptional case of cardiac chest pain. Familiarizing ourselves with the more common causes of chest pain and with our present approach to the evaluation of this particular chief complaint, may help us to better counsel our patients and avoid unnecessary use of valuable resources.

Accuracy of the ECG for differential diagnosis between hypertrophic cardiomyopathy and athlete’s heart: comparison between the European Society of Cardiology (2010) and International (2017) criteria

Background

Interpretation of the athlete’s ECG is based on differentiation between benign ECG changes and potentially pathological abnormalities. The aim of the study was to compare the 2010 European Society of Cardiology (ESC) and the 2017 International criteria for differential diagnosis between hypertrophic cardiomyopathy (HCM) and athlete’s heart.

Methods

The study populations included 200 patients with HCM and 563 athletes grouped as follows: ‘group 1’, including normal ECG and isolated increase of QRS voltages, which are considered non-pathologic according to ESC and International criteria; ‘group 2’, including left atrial enlargement or left axis deviation in isolation and Q-waves with an amplitude ≥4 mm but <25% of the ensuing R-wave and a duration <0.04 s which are considered pathologic according to the ESC but not according to the International criteria; and ‘group 3’, including abnormalities which are considered pathologic according to ESC and International criteria.

Results

Overall, the 2010 ESC criteria showed a sensitivity of 95.5% and a specificity of 86.9%. Considering group 2 ECG changes as normal according to the International criteria led to a statistically significant (p<0.001) increase of specificity to 95.9%, associated with a non-significant (p=0.47) reduction of sensitivity to 93%. Among patients with HCM, there was a significant increase of maximal left ventricular wall thickness from group 1 to 3 (p=0.02).

Conclusions

The use of 2017 International criteria is associated with a substantial increase in specificity and a marginal decrease in sensitivity for differential diagnosis between HCM and athlete’s heart.

Cardiac screening to prevent sudden death in young athletes

Sudden cardiac death (SCD) is a sudden and unexpected death caused by loss of heart of function. SCD may occur in any population, but when it occurs on the playing field in a young individual, communities worldwide are affected. Although these events are rare, media coverage of sudden cardiac arrests in young athletes have created the impression that these events are far more common than they appear. With a heightened awareness of SCD in young athletes, screening methods have been developed to try and prevent these events from occurring. The American Heart Associations (AHA) currently employs history and physical examination alone during the preparticipation physical exam (PPE), which clears a young athlete for participation in sports. There has been recent discussion on whether to include screening electrocardiogram (ECG) in the PPE especially after one study in Italy by Corrado et al. found that using routine ECG reduced the annual incidence of SCD by 90%. In this article we will discuss how effective the current screening recommendations are, whether routine ECG use should be included in the PPE and if it is cost effective, and review other screening modalities that may be useful in the detection of young athletes at risk for SCD.

Sudden death in athletes

Competitive sports activity is associated with an increased risk of sudden cardiovascular death (SCD) in adolescents and young adults with clinically silent cardiovascular disorders. While in middle-aged/senior athletes atherosclerotic coronary artery disease accounts for the vast majority of SCDs, in young athletes the spectrum of substrates is wider and includes inherited (cardiomyopathies) and congenital (anomalous origin of coronary arteries) structural heart diseases. Inherited ion channel diseases have been implicated in SCDs occurring with an apparently normal heart at autopsy. Screening including the ECG allows identification of athletes affected by heart muscle diseases at a pre-symptomatic stage and may lead to reduction of the risk of SCD during sports. The use of modern criteria for interpretation of the ECG in the athlete offers the potential to improve the screening accuracy by reducing the number of false positives. Screening with exercise testing middle aged/senior athletes engaged in leisure sports activity is likely to be effective in patients with significant coronary risk factors, while it is not useful in low-risk subgroups. The availability of automated external defibrillator on the athletic field provides a "back-up" preventive strategy for unpredictable arrhythmic cardiac arrest, mostly occurring in patients with coronary artery diseases.

Exercise and Arrhythmias: A Double-Edged Sword

Ample evidence indicates that moderate regular exercise is beneficial for both normal individuals and patients with cardiovascular (CV) disease. However, intense and strenuous exercise in individuals with evident or occult underlying CV abnormalities may have adverse effects with provocation and exacerbation of arrhythmias that may lead to life-threatening situations. Both of these aspects of exercise-induced effects are herein reviewed.

Electrocardiographic Predictors of Cardiovascular Mortality

Cardiovascular diseases are the main causes of mortality. Sudden cardiac death may also appear in athletes, due to underlying congenital or inherited cardiac abnormalities. The electrocardiogram is used in clinical practice and clinical trials, as a valid, reliable, accessible, inexpensive method. The aim of the present paper was to review electrocardiographic (ECG) signs associated with cardiovascular mortality and the mechanisms underlying those associations, providing a brief description of the main studies in this area, and consider their implication for clinical practice in the general population and athletes. The main ECG parameters associated with cardiovascular mortality in the present paper are the P wave (duration, interatrial block, and deep terminal negativity of the P wave in V1), prolonged QT and Tpeak-Tend intervals, QRS duration and fragmentation, bundle branch block, ST segment depression and elevation, T waves (inverted, T wave axes), spatial angles between QRS and T vectors, premature ventricular contractions, and ECG hypertrophy criteria.