Interpreting the Athlete's ECG: Current State and Future Perspectives

Athlete's ECG Made Easy: A Practical Guide to Surviving Everyday Clinical Practice

Electrocardiogram modifications in athletes are common and usually reflect structural and electrical heart adaptations to regular physical training, known as the athlete's heart. However, these electrical modifications sometimes overlap with electrocardiogram findings that are characteristic of various heart diseases. A missed or incorrect diagnosis can significantly impact a young athlete's life and potentially have fatal consequences during exercise, such as sudden cardiac death, which is the leading cause of death in athletes. Therefore, it is crucial to correctly distinguish between expected exercise-related electrocardiogram changes in an athlete and several electrocardiogram abnormalities that may indicate underlying heart disease. This review aims to serve as a practical guide for cardiologists and sports clinicians, helping to define normal and physiology-induced electrocardiogram findings from those borderlines or pathological, and indicating when further investigations are necessary. Therefore, the possible athlete's electrocardiogram findings, including rhythm or myocardial adaptation, will be analyzed here, focusing mainly on the differentiation from pathological findings.

Racial Disparities in Sports Cardiology: A Review

Importance

Racial disparities in cardiovascular health, including sudden cardiac death (SCD), exist among both the general and athlete populations. Among competitive athletes, disparities in health outcomes potentially influenced by social determinants of health (SDOH) and structural racism remain inadequately understood. This narrative review centers on race in sports cardiology, addressing racial disparities in SCD risk, false-positive cardiac screening rates among athletes, and the prevalence of left ventricular hypertrophy, and encourages a reexamination of race-based practices in sports cardiology, such as the interpretation of screening 12-lead electrocardiogram findings.

Observations

Drawing from an array of sources, including epidemiological data and broader medical literature, this narrative review discusses racial disparities in sports cardiology and calls for a paradigm shift in approach that encompasses 3 key principles: race-conscious awareness, clinical inclusivity, and research-driven refinement of clinical practice. These proposed principles call for a shift away from race-based assumptions towards individualized, health-focused care in sports cardiology. This shift would include fostering awareness of sociopolitical constructs, diversifying the medical team workforce, and conducting diverse, evidence-based research to better understand disparities and address inequities in sports cardiology care.

Conclusions and Relevance

In sports cardiology, inadequate consideration of the impact of structural racism and SDOH on racial disparities in health outcomes among athletes has resulted in potential biases in current normative standards and in the clinical approach to the cardiovascular care of athletes. An evidence-based approach to successfully address disparities requires pivoting from outdated race-based practices to a race-conscious framework to better understand and improve health care outcomes for diverse athletic populations.

Wide Spectrum of Bradyarrhythmias and Supraventricular Tachyarrhythmias in Sportsmen: Run Forrest, Run?!

The intricate relationship between sports participation and cardiac arrhythmias is a key focus of cardiovascular research. Physical activity, integral to preventing atherosclerotic cardiovascular disease, induces structural, functional, and electrical changes in the heart, potentially triggering arrhythmias, particularly atrial fibrillation (AF). Despite the cardiovascular benefits, the optimal exercise amount remains unclear, revealing a J-shaped association between AF and exercise. Endurance athletes, particularly males, face elevated AF risks, influenced by age. Risk factors vary among sports modalities, with unique physiological responses in swim training potentially elevating AF risk. Clinical management of AF in athletes necessitates a delicate balance between rhythm control, rate control, and anticoagulation therapy. Sport-induced bradyarrhythmias, including sinus bradycardia and conduction disturbances, are prevalent among athletes. Managing bradycardia in athletes proves challenging due to its complex and not fully understood pathophysiology. Careful consideration is required, particularly in symptomatic cases, where pacemaker implantation may be necessary for sinus node dysfunction. Although pacing is recommended for specific atrioventricular (AV) blocks, milder forms often prevail without restricting sports participation. This review explores the nuanced relationship between exercise and tachy- and bradyarrhythmia in athletes, addressing the challenges clinicians face when optimizing patient care in this distinctive population.

Identifying Sudden Cardiac Arrest Risk in Adolescent Male Athletes

The purpose of the study was to determine the prevalence of sudden cardiac arrest (SCA) risk factors in high school (HS) athletes. Thirty-three male soccer players from a public HS in the southeastern United States (ages 14-17) self-reported survey data. Participants reported demographic, lifestyle, heart health, COVID-19 history, and symptoms indicative of SCA risk. An electrocardiogram (ECG) assessed heart rate (HR), rhythm, and electrical activity. Resting HR and blood pressure (BP) were measured with a BP monitor. The association between COVID-19 history, HR, and BP were calculated. Participants were divided into ECG groups (normal or abnormal). Independent t-tests assessed comparisons between groups to identify SCA risk. Over 50% of participants (n=17) reported experiencing shortness of breath (SOB) and 30% (n=10) reported chest pain. A history of chest pain was associated with abnormal ECGs (p<0.04). Thirteen (39.4%) participants reported a COVID-19 history. Of these, 5 presented with persisting symptoms, 2 with elevated HR, and 3 with elevated BP. Eleven (33.3%) participants had an abnormal ECG and of these eleven, 8 (72.7%) reported a positive COVID-19 history (p<0.01). The current American Heart Association suggested screening method is limited. An ECG should be used in preparticipation screenings (PPS) and return to participation (RTP) decisions for athletes with a COVID-19 history. Family cardiac history, chest pain during exercise, and an abnormal QRS interval should be used to identify SCA risk.

Do athletic ECG changes predict athletic performance in Gurkha recruits?

INTRODUCTION

ECG changes are associated with regular long-term intensive exercise due to electrical manifestations of increased vagal tone, increased ventricular wall thickness and enlarged chamber size. The aim of this study was to further understand the relationship of athletic ECG changes and athletic performance in an athletic population.

METHODS

A retrospective cohort study was performed in 195 Nepali civilian males undergoing selection to the Gurkhas. V̇O2max (maximal oxygen consumption) was estimated from a 1.5-mile run time using Cooper's formula and correlated with athletic ECG adaptations. Variables were explored with univariable and multivariable linear regression.

RESULTS

The median number of athletic changes on ECG was 2 (IQR 1-2). There was no significant correlation (p=0.46) between the number of ECG adaptations and the degree of cardiovascular fitness by estimated V̇O2max (estV̇O2max). We found a negligible but significant correlation between the presence of inferior T wave inversion (TWI) and estV̇O2max (R2=0.03, p=0.02). The multivariable-fitted regression model was: estV̇O2max~Intercept+presence of RVH (right ventricular hypertrophy) voltage criteria+absence of sinus arrhythmia+T wave axis+inferior TWI. The overall regression was statistically significant: R2=0.10, F(df=4, df=189)=[5.4], p=0.0004). All variables in the multivariable model significantly predicted estV̇O2max (p<0.04).

CONCLUSION

ECG changes of athleticism negligibly predict and differentiate athletic performance in our athletic population. The most predictive ECG markers being voltage criteria for left ventricular hypertrophy and RVH. Markers of increased vagal tone were not predictive. TWI, being a marker for disease, was also a marker for athletic performance in this cohort. The number of athletic ECG adaptations did not predict increased athletic performance.

Does cardiovascular preparticipation screening cause psychological distress in athletes? A systematic review

OBJECTIVE

To evaluate the psychological implications of cardiovascular preparticipation screening (PPS) in athletes.

DESIGN

Systematic review.

DATA SOURCES

MEDLINE, EMBASE, PubMed, CINAHL, SPORTDiscus, APA PsycInfo, Cochrane Library and grey literature sources.

STUDY ELIGIBILITY CRITERIA

Observational and experimental studies assessing a population of athletes who participated in a cardiovascular PPS protocol, where psychological outcomes before, during and/or after PPS were reported.

METHODS

Results of included studies were synthesised by consolidating similar study-reported measures for key psychological outcomes before, during and/or after screening. Summary measures (medians, ranges) were computed across studies for each psychological outcome.

RESULTS

A total of eight studies were included in this review (median sample size: 479). Study cohorts consisted of high school, collegiate, professional and recreational athletes (medians: 59% male, 20.5 years). Most athletes reported positive reactions to screening and would recommend it to others (range 88%-100%, five studies). Increased psychological distress was mainly reported among athletes detected with pathological cardiac conditions and true-positive screening results. In comparison, athletes with false-positive screening results still reported an increased feeling of safety while participating in sport and were satisfied with PPS. A universal conclusion across all studies was that most athletes did not experience psychological distress before, during or after PPS, regardless of the screening modality used or accuracy of results.

CONCLUSION

Psychological distress associated with PPS in athletes is rare and limited to athletes with true-positive findings. To mitigate downstream consequences in athletes who experience psychological distress, appropriate interventions and resources should be accessible prior to the screening procedure.

PROSPERO REGISTRATION NUMBER

CRD42021272887.

The Relationship between the Frontal QRS-T Angle on ECG and Physical Activity Level in Young Adults

BACKGROUND

The heart's electrical activity has been the subject of numerous research concerning various physiological parameters. The frontal QRS-T angle (FQRST) is an advanced ECG variable with clinical epidemiological utility. This study aimed to determine the relationship between FQRST and physical activity exposure among young adults.

METHODS

We recorded the ECG with 12 leads of 124 participants (mean age 20.28 ± 2.23 years, age range 18-27 years). Next, we measured their physical activity level (PAL) with the International Physical Activity Questionnaire-Short Form (IPAQ), which categorizes activity into three classes: low, moderate, or high.

RESULTS

An inferential analysis, based on the Kruskal-Wallis H test and Mann-Whitney U test, revealed a statistically significant difference in FQRST between the three groups of subjects, classified by their PAL (p < 0.001). We also identified a significant regression model between the body mass index (BMI) and the FQRST (p < 0.001).

CONCLUSIONS

The physical activity regime of young adults significantly influences the concordance between ventricular depolarization and repolarization, reflected in the FQRST's width. Also, we found a regression model between FQRST and BMI with statistical significance.

High Number of Medical Conditions Detected in Elite Athlete Periodic Health Evaluations, But Only Mild Consequences

OBJECTIVE

To evaluate the number of medical conditions detected by periodic health evaluations (PHEs) in elite athletes, and their consequences for management and medical clearance.

DESIGN

Retrospective design.

PARTICIPANTS

Elite athletes of various sports in a high-performance program in The Netherlands, in the period between 2009 and 2020.

INTERVENTIONS

The PHEs consisted of a questionnaire, general and musculoskeletal physical examination, laboratory blood test, electrocardiogram, pulmonary function testing, and (cardiopulmonary) exercise test.

MAIN OUTCOME MEASURES

We extracted and analyzed the medical conditions that led to advice, clinical follow-up, further diagnostic investigation or treatment, and the medical clearance status of the athlete (clearance, temporarily no clearance, or permanently no clearance).

RESULTS

We included 721 PHEs of 451 elite athletes. We found 1389 medical conditions that led to advice (n = 923, 66%), clinical follow-up (n = 124, 9%), further diagnostic investigation (n = 190, 14%), treatment (n = 132, 10%), or sports restriction (n = 20, 1%). Only 20 cases (3%) led to temporarily no medical clearance. After further investigation or treatment, no permanent sports restriction was imposed on any of the athletes.

CONCLUSIONS

We found a high number of medical conditions detected with a PHE in elite athletes. However, the vast majority of detected conditions were mild, with consequences limited to preventive advice and follow-up. The yield of PHE to detect (potentially) severe pathological conditions seems low. Clinical relevance of PHE in elite athletes and potential future health benefits remain unclear.

Patterns of resting electrocardiogram of male college track and field athletes

This study sought to determine the resting Electrocardiogram of male college Track and Field athletes, with a view to identifying electrocardiographic changes attributable to cardiac adaptations and possible differences in ECG morphologies by the athletic event. A descriptive survey design was used in the study. The population was male track and field athletes of Obafemi Awolowo University (OAU), Ile-Ife, Nigeria. Eighteen athletes; track (n=10) and field (n=8), were purposively selected from the OAU Athletics team that participated in the 14th West-African Universities’ Games, held at the University of Port-Harcourt, Rivers State Nigeria in 2018. Resting ECG was recorded with a 12-lead Electrocardiograph (SCHILLER-Cardiovit AT-2 plus), blood pressure was recorded with a digital blood pressure monitor (OMRON-M6 Comfort), weight, height, and BMI were recorded with an electronic BMI scale (SECA-220). Descriptive statistic of mean and standard deviation was computed and a paired-sample t-test was used to compare the resting ECG of athletes in the two divisions. Track and field athletes had mean RR-interval, P-wave, PR-interval, QRS-interval, QT-interval, and QTc of 993.22 ± 111.51ms, 97.12 ± 10.87ms, 157.00 ± 34.34ms, 120.67 ± 58.22ms, 376.94 ± 55.34ms and 416.78 ± 46.98mm respectively. With regards to voltage, athletes had mean voltages of 0.11 ± 0.09mm, -0.98 ± 0.77mm, and 1.54 ± 0.73mm for P-wave in lead II, S in VI, and R in V5 respectively. When athletes’ ECGs in the two divisions were compared, a significant difference was only found in the RR-interval (t = -3.08; P < 0.05). The study concluded that there were no distinctive morphological differences in the resting ECG of Nigerian collegiate track and field athletes.

The Impact of Ethnicity on Athlete ECG Interpretation: A Systematic Review

Athlete ECG interpretation criteria have been developed and refined from research in athlete populations; however, current guidelines are based on available data primarily from Caucasian and Black athletes. This study aimed to assess the impact of ethnicity on ECG interpretation in athletes. A systematic review was conducted of the MEDLINE, EMBASE, Scopus, SPORTDiscus, and Web of Science databases, for papers that assessed athlete screening ECGs and compared findings on the basis of ethnicity. Fifty-one papers which compared ECGs from various ethnicities were included. Most studies assessed Black athletes against Caucasian athletes and found a greater prevalence of T-wave inversion (TWI) (2.6–22.8% vs. 0–5.0%) and anterior TWI (3.7–14.3% vs. 0.6–2.0%). Black athlete subgroups in Africa had TWI (20–40%) and anterior TWI (4.3–18.7%) at a higher prevalence than other Black athletes. Athletes who were defined as mixed-race, Asian, and Pacific Islander are potentially more like Black athletes than Caucasian athletes. Black ethnicity is known to have an impact on the accurate interpretation of athlete ECGs; however, there is nuance related to origin of both parents. Asian and Pacific Islander origin also may impact athlete ECG interpretation. Further research is required to assist in distinguishing abnormal and normal athlete ECGs in different ethnic populations.

Electrocardiographic and Echocardiographic Insights From a Prospective Registry of Asian Elite Athletes

Background: Asian representation in sport is increasing, yet there remains a lack of reference values for the Asian athlete's heart. Consequently, current guidelines for cardiovascular screening recommend using Caucasian athletes' norms to evaluate Asian athletes. This study aims to outline electrocardiographic and echocardiographic characteristics of the Asian athlete's heart using a Singaporean prospective registry of Southeast (SE) Asian athletes.

Methods and Results: One hundred and fifty elite athletes, mean age of 26.1 ± 5.7 years (50% males, 88% Chinese), were evaluated using a questionnaire, 12-lead electrocardiogram (ECG) and transthoracic echocardiogram. All ECGs were analyzed using the 2017 International Recommendations. Echocardiographic data were presented by gender and sporting discipline. The prevalence of abnormal ECGs among SE Asian athletes was 6.7%—higher than reported figures for Caucasian athletes. The abnormal ECGs comprised mainly anterior T wave inversions (ATWI) beyond lead V2, predominantly in female athletes from mixed/endurance sport (9.3% prevalence amongst females). None had echocardiographic structural abnormalities. Male athletes had reduced global longitudinal strain compared to females (−18.7 ± 1.6 vs. −20.7 ± 2.1%, p < 0.001). Overall, SE Asian athletes had smaller left ventricular cavity sizes and wall thickness compared to non-Asian athletes.

Conclusion: SE Asian athletes have higher abnormal ECG rates compared to Caucasian athletes, and also demonstrate structural differences that should be accounted for when interpreting their echocardiograms compared to athletes of other ethnicities.

Sports Activity and Arrhythmic Risk in Cardiomyopathies and Channelopathies: A Critical Review of European Guidelines on Sports Cardiology in Patients with Cardiovascular Diseases

The prediction and prevention of sudden cardiac death is the philosopher’s stone of clinical cardiac electrophysiology. Sports can act as triggers of fatal arrhythmias and therefore it is essential to promptly frame the athlete at risk and to carefully evaluate the suitability for both competitive and recreational sports activity. A history of syncope or palpitations, the presence of premature ventricular complexes or more complex arrhythmias, a reduced left ventricular systolic function, or the presence of known or familiar heart disease should prompt a thorough evaluation with second level examinations. In this regard, cardiac magnetic resonance and electrophysiological study play important roles in the diagnostic work-up. The role of genetics is increasing both in cardiomyopathies and in channelopathies, and a careful evaluation must be focused on genotype positive/phenotype negative subjects. In addition to being a trigger for fatal arrhythmias in certain cardiomyopathies, sports also play a role in the progression of the disease itself, especially in the case arrhythmogenic right ventricular cardiomyopathy. In this paper, we review the latest European guidelines on sport cardiology in patients with cardiovascular diseases, focusing on arrhythmic risk stratification and the management of cardiomyopathies and channelopathies.

Electrocardiographic interpretation in athletes

Participation in regular exercise of moderate intensity is associated with a plethora of systemic benefits, including a reduction in risk factors for coronary atherosclerosis; however, intensive exercise may paradoxically culminate in sudden cardiac arrest among individuals harboring arrhythmogenic substrates. The precise mechanism for arrhythmogenesis is likely multifactorial, however, surges in catecholamines, electrolyte shifts, acid-base disturbances, increased core temperature and demand myocardial ischemia are potential contributors. Although most deaths occur in middle aged and older males with atherosclerotic coronary artery disease, a significant proportion also affect young athletes with inherited or congenital cardiac abnormalities. The impact of such catastrophes on society, particularly when a young high-profile athlete is affected could be considered a justified reason for identifying individuals who may be at risk. Given the rarity of deaths in young athletes, only the simplest screening test, such as the 12-lead electrocardiography (ECG) may be considered to be cost effective. The ECG is effective for detecting serious electrical diseases in young athletes such as congenital electrical accessory pathways and ion channel diseases but can also identify athletes with potential life-threatening structural diseases such as hypertrophic and arrhythmogenic cardiomyopathy. One of the concerns about ECG screening is that regular intensive exercise results in several physiological alterations in cardiac structure and function that are reflected on the athlete's ECG. Sinus bradycardia, first-degree atrioventricular block, incomplete right bundle branch block, minor J-point elevation and large QRS voltages are common. Conversely, some repolarization anomalies affecting the ST segment, T waves and QT interval may overlap with patterns observed in patients with serious cardiac diseases. The situation is complicated further because age, sex and ethnicity of the athletes also influence the ECG and there is a risk that erroneous interpretation could have serious consequences. This review will describe the normal electrical patterns of the "athlete's heart" and provide insights into differentiation physiological electrical patterns from those observed in serious cardiac disease.