Recognition and Significance of Pathological T-Wave Inversions in Athletes

Hypertrophic cardiomyopathy and competitive sports: let 'em play?

PURPOSE OF REVIEW

Hypertrophic cardiomyopathy (HCM) is one of the most common cardiovascular genetic conditions. Although most patients with HCM typically do well clinically, there is a small but real incidence of sudden cardiac death. A diagnosis of HCM was previously a reason for complete exclusion in sports, particularly competitive sports.However, many of these recommendations are based on expert consensus, and much data has been published in the last decade furthering the scientific knowledge in this area, and allowing athletes who may have been previously excluded the potential to participate in strenuous activities and competitive sports.

RECENT FINDINGS

With recent publications on participation in sports with HCM, as well as an emphasis on shared decision-making, more athletes with HCM are participating in competitive sports, even at a professional level. Even contact sports in the presence of an implantable cardioverter-defibrillator are no longer mutually exclusive in the current era.

SUMMARY

Previous guidelines were likely overly restrictive for patients with HCM. Although there is a risk of sudden death that cannot be ignored, the potential for shared decision making as well as medical guidance are entering a new era in all aspects of medicine, particularly in sports participation.

Prevalence and prognosis of structural heart disease among athletes with negative T waves and normal transthoracic echocardiography

INTRODUCTION

The aim of the present study was to evaluate the prevalence and prognosis of structural heart disease (SHD) among competitive athletes with negative T waves without pathological findings at transthoracic echocardiogram.

METHODS

From a prospective register of 450 athletes consecutively evaluated during a second-level cardiological examination, we retrospectively identified all subjects with the following inclusion criteria: (1) not previously known cardiovascular disease; (2) negative T waves in leads other than V1-V2; (3) normal transthoracic echocardiogram. Patients underwent cardiac MRI and CT. The primary endpoint was the diagnosis of definite SHD after multimodality imaging evaluation. A follow-up was collected for a combined end-point of sudden death, resuscitated sudden cardiac death and hospitalization for any cardiovascular causes.

RESULTS

A total of 55 competitive athletes were finally enrolled (50 males, 90%) with a mean age of 27.5 ± 14.1 years. Among the population enrolled 16 (29.1%) athletes had a final diagnosis of SHD. At multivariate analysis, only deep negative T waves remained statistically significant [OR (95% CI) 7.81 (1.24-49.08), p = 0.0285]. Contemporary identification of deep negative T waves and complex arrhythmias in the same patients appeared to have an incremental diagnostic value. No events were collected at 49.3 ± 12.3 months of follow-up.

CONCLUSIONS

In a cohort of athletes with negative T waves at ECG, cardiac MRI (and selected use of cardiac CT) enabled the identification of 16 (29.1%) subjects with SHD despite normal transthoracic echocardiography. Deep negative T waves and complex ventricular arrhythmias were the only clinical characteristic associated with SHD diagnosis.

Imaging associations enhance the understanding of ECG abnormalities in male Brazilian football players: findings from the B-Pro Foot ECG study

OBJECTIVES

To evaluate the prevalence of abnormal ECG findings and their association with imaging results in male Brazilian football players.

METHODS

The 'B-Pro Foot ECG' is a multicentre observational study conducted in 82 Brazilian professional clubs. It analysed 6125 players aged 15-35 years (2496 white, 2004 mixed-race and 1625 black individuals) who underwent cardiovascular screening from 2002 to 2023. All ECGs were reviewed by two experienced cardiologists in the athlete's care. Those with abnormal findings underwent further investigations, including a transthoracic echocardiogram (TTE). Cardiac magnetic resonance (CMR) was subsequently performed based on TTE findings or clinical suspicion.

RESULTS

In total, 180 (3%) players had abnormal ECGs and 176 (98%) showed normal TTE results. Athletes aged 26-35 years had a higher prevalence of abnormal ECGs than younger athletes (15-25 years). Black players had a higher prevalence of T-wave inversion (TWI) in the inferior leads than white players (2.6% vs 1.4%; p=0.005), as well as in V5 (2.9%) and V6 (2.1%) compared with white (1.2% and 1.0%; p<0.001) and mixed-race (1.5% and 1.2%; p<0.05) players, respectively. TTE parameters were similar across ethnicities. However, four out of 75 players with inferolateral TWI showed abnormal TTEs and CMR findings consistent with cardiomyopathies. CMR also showed cardiomyopathies or myocarditis in four players with inferolateral TWI and normal TTEs. In total, nine (0.1%) athletes were diagnosed with cardiac diseases and were followed for 40±30 months, with no cardiac events documented.

CONCLUSION

This study found a 3% prevalence of abnormal ECGs in male Brazilian football players. Inferolateral TWI was associated with cardiac pathologies confirmed by CMR, even in athletes with a normal TTE.

Right ventricular assessment of the adolescent footballer's heart

INTRODUCTION

Athletic training can result in electrical and structural changes of the right ventricle that may mimic phenotypical features of arrhythmogenic right ventricular cardiomyopathy (ARVC), such as T-wave inversion and right heart dilatation. An erroneous interpretation may have consequences ranging from false reassurance in an athlete vulnerable to cardiac arrhythmias, to unnecessary sports restriction in a healthy individual. The primary aim of this study was to define normal RV dimension reference ranges for academy adolescent footballers of different ethnicities. Secondary aims include analysis of potential overlap between this adolescent group with ARVC criteria and comparison with normal adult ranges.

RESULTS

Electrocardiographic (ECG) and echocardiographic data of 1087 academy male footballers aged between 13 and 18 years old (mean age 16.0 ± 0.5 years), attending mandatory cardiac screening were analysed. Ethnicity was categorised as white (n = 826), black (African/Caribbean; n = 166) and mixed-race (one parent white and one parent black; n = 95). Arrhythmogenic right ventricular cardiomyopathy major criteria for T-wave inversion was seen in 3.3% of the cohort. This was more prevalent in black footballers (12%) when compared to mixed race footballers (6.3%) or white footballers (1%), P < 0.05. Up to 59% of the cohort exceeded adult reference ranges for some of the right ventricular parameters, although values were similar to those seen in adult footballers. There were no differences in right ventricular dimensions between ethnicities. In particular, the right ventricular outflow tract diameter would fulfil major criteria for ARVC dimension in 12% of footballers. Overall, 0.2% of the cohort would fulfil diagnosis for 'definite' arrhythmogenic right ventricular cardiomyopathy and 2.2% would fulfil diagnosis for 'borderline' arrhythmogenic right ventricular cardiomyopathy for RV dimensions and ECG changes. This was seen more frequently in black footballers (9.9%) than mixed race footballers (3.9%) or white footballer (0.6%), P < 0.05. Among athletes meeting definite or borderline arrhythmogenic right ventricular cardiomyopathy criteria, no cardiomyopathy was identified after comprehensive clinical assessment, including with cardiac magnetic resonance imaging, exercise testing, ambulatory electrocardiograms and familial evaluation.

CONCLUSION

Right heart sizes in excess of accepted adult ranges occurred in as many as one in two adolescent footballers. Structural adaptations in conjunction with anterior T-wave inversion may raise concern for ARVC, highlighting the need for evaluation in expert settings.

Electrocardiographic findings in pediatric versus young-adolescent athletes: A comparative analysis using general international criteria

BACKGROUND

The inclusion of electrocardiogram (ECG) in medical examinations for sports practice serves as a valuable tool for identifying potential life-threatening conditions during physical exercise. However, its applicability in young individuals remains a subject of controversy, primarily due to relatively high rates of false positives and the associated costs of further investigations. Furthermore, the validation of International Criteria for athletes below 12 years of age in optimizing pre-participation screening for young athletes is yet to be established. In light of these considerations, this study aims to describe the prevalence of ECG findings in a sample of children and young-adolescent athletes aged 11-16 years, employing refined Seattle interpretation criteria. Additionally, we seek to compare these findings based on age group and sex.

METHODS

This was a retrospective and observational study of 3747 athletes 11-16 year-olds. Evaluation included interviewer-administered questionnaires for relevant history, physical examination and resting 12 - lead ECG for each participant. The primary outcome measure was abnormal ECG findings according to the International Recommendations for Electrocardiographic Interpretation in Athletes.

RESULTS

Among the evaluated population of pediatric and young adolescent athletes (77.5% boys; >99% Caucasian), the vast majority exhibited normal electrocardiogram (ECG) results, with adaptive findings related to sports participation being more frequent among young adolescents and males. The presence of significant ECG abnormalities in young-adolescent athletes was uncommon (2.05%; 1.92% children and 2.32% young-adolescent) and required additional examinations. 0.27% of the total population were diagnosed with a previously unknown cardiac pathology only through the ECG.

CONCLUSIONS

This study provides valuable insights into the prevalence of normal, borderline, and abnormal electrocardiogram (ECG) findings in a large population of pediatric and young-adolescent athletes. These findings serve as guidance in detecting potentially serious cardiac alterations within this specific group, considering variations based on age and sex. The study confirms that ECG screening is a useful tool for identifying cardiac abnormalities in pediatric and young-adolescent athletes, even though the prevalence of significant findings in this population is relatively low. Furthermore, our findings support the utilization of the refined Seattle criteria as a sensitive and specific technique for screening pediatric and young-adolescent athletes, further enhancing the accuracy of ECG-based evaluations.

Outcomes of Investigating T Wave Inversion With Echocardiography in an Unselected Young Male Preparticipation Cohort

BACKGROUND Electrocardiography (ECG) may be performed as part of preparticipation sports screening. Recommendations on screening of athletes to identify individuals with previously unrecognized cardiac disease are robust; however, data guiding the preparticipation screening of unselected populations are scarce. T wave inversion (TWI) on ECG may suggest an undiagnosed cardiomyopathy. This study aims to describe the prevalence of abnormal TWI in an unselected young male cohort and the outcomes of an echocardiography-guided approach to investigating these individuals for structural heart diseases, focusing on the yield for cardiomyopathies. METHODS AND RESULTS Consecutive young male individuals undergoing a national preparticipation cardiac screening program for 39 months were studied. All underwent resting supine 12-lead ECG. Those manifesting abnormal TWI, defined as negatively deflected T waves of at least 0.1 mV amplitude in any 2 contiguous leads, underwent echocardiography. A total of 69 714 male individuals with a mean age of 17.9±1.1 years were studied. Of the individuals, 562 (0.8%) displayed abnormal TWI. This was most frequently observed in the anterior territory and least so in the lateral territory. A total of 12 individuals (2.1%) were diagnosed with a cardiomyopathy. Cardiomyopathy diagnoses were significantly associated with deeper maximum TWI depth and the presence of abnormal TWI in the lateral territory, but not with abnormal TWI in the anterior and inferior territories. No individual presenting with TWI restricted to solely leads V1 to V2, 2 inferior leads or both was diagnosed with a cardiomyopathy. CONCLUSIONS Cardiomyopathy diagnoses were more strongly associated with certain patterns of abnormal TWI. Our findings may support decisions to prioritize echocardiography in these individuals.

Reference ventricular dimensions and function parameters by cardiovascular magnetic resonance in highly trained Caucasian athletes

BACKGROUND

Data regarding cardiovascular magnetic resonance (CMR) reference values in athletes have not been well determined yet. Using CMR normal reference values derived from the general population may be misleading in athletes and may have clinical implications.

AIMS

To determine reference ventricular dimensions and function parameters and ratios by CMR in high performance athletes.

METHODS

Elite athletes and age- and gender-matched sedentary healthy controls were included. Anatomical and functional variables, including biventricular volumes, mass, systolic function, wall thickness, sphericity index and longitudinal function were determined by CMR.

RESULTS

A total of 148 athletes (29.2 ± 9.1 years; 64.8% men) and 124 controls (32.1 ± 10.5 years; 67.7% men) were included. Left ventricular (LV) mass excluding papillary muscles was 67 ± 13 g/m2 in the control group and increased from 65 ± 14 g/m2 in the low intensity sport category to 83 ± 16 g/m2 in the high cardiovascular demand sport category; P < 0.001. Regarding right ventricular (RV) mass, the data were 20 ± 5, 31 ± 6, and 38 ± 8 g/m2, respectively; P < 0.001. LV and RV volumes, and wall thickness were higher in athletes than in the control group, and also increased with sport category. However, LV and RV ejection fractions were similar in both groups. LV and RV dimensions, wall thickness and LV/RV ratios reference parameters for athletes are provided.

CONCLUSIONS

LV and RV masses, volumes, and wall thicknesses are higher in athletes than in sedentary subjects. Specific CMR reference ranges for athletes are provided and can be used as reference levels, rather than the standard upper limits used for the general population to exclude cardiomyopathy.

Guide to the Female Student Athlete ECG: A Comprehensive Study of 3466 Young, Racially Diverse Athletes

OBJECTIVES

The 12-lead electrocardiogram (ECG) is used in the preparticipation screening examination for athletes. Despite known differences in ECG findings by sex, only QTc prolongation is given a sex-specific threshold. We hypothesize that our large dataset-with diversity in age, race, and sport participation-can be utilized to improve ECG screening in female student athletes.

METHODS

Computerized 12-lead ECGs were recorded and analyzed in female athletes who underwent preparticipation screening examination between June 2010 and September 2021. The quantitative, empirical 2017 international criteria for electrocardiographic interpretation were compared with either the 99th percentile in our cohort or the percentile that corresponded to the known disease prevalence.

RESULTS

Of 3466 female athletes with ECGs as part of preparticipation screening examination, the 2017 international criteria classified 2.1% of athletes with at least one ECG abnormality requiring cardiological evaluation. Rates were similar across age, race/ethnicity, and sporting discipline. Using ranges based on our population, 2.7% of athletes would require additional workup. Surprisingly, ST depression up to 0.03 mV was a normal finding in this cohort. If RS voltage extremes were considered findings requiring follow-up, an additional 9.6% of the athlete population would be flagged using current definitions. This number decreases to 2.7% if using the 99th percentile in this cohort.

CONCLUSION

These results highlight a difference in the reported prevalence of ECG abnormalities when comparing empirically derived thresholds to statistically derived ranges. Consideration of new metrics specific to the female athlete population has the potential to further refine athlete ECG screening.

Differentiating Physiology from Pathology: The Gray Zones of the Athlete's Heart

Routine vigorous exercise can lead to electrical, structural, and functional adaptations that can enhance exercise performance. There are several factors that determine the type and magnitude of exercise-induced cardiac remodeling (EICR) in trained athletes. In some athletes with pronounced cardiac remodeling, there can be an overlap in morphologic features with mild forms of cardiomyopathy creating gray zone scenarios whereby distinguishing health from disease can be difficult. An integrated clinical approach that factors athlete-specific characteristics (sex, size, sport, ethnicity, and training history) and findings from multimodality imaging are essential to help make this distinction.

New Precordial T Wave Inversions in Hospitalized Patients

BACKGROUND

The incidence of precordial T changes has been described in athletes and in specific populations, while the etiology in a large patient population admitted to the hospital has not previously been reported.

METHODS

All electrocardiograms (ECGs) read by the same physician with new (compared to prior ECGs) or presumed new (no prior ECGs) precordial T wave inversions of >1 mm (0.1 mV) in multiple precordial leads were retrospectively reviewed and various ECG, patient-related, and imaging parameters assessed. A total of 226 patients and their ECGs were initially selected for analysis. Of these, 35 were eliminated leaving 191 for the final analysis.

RESULTS

Patients and their ECGs were divided into 5 groups based on diagnosis and incidence including Wellens syndrome, takotsubo, type 2 myocardial infarction, other (including multiple diagnoses), and unknown. Although subtle differences including number of T inversion leads, depth of T waves, QTc intervals, and other variables were present between some groups, diagnosis in individual cases required appropriate clinical, laboratory, or imaging studies. For example, although Wellens syndrome was identified in <20% of cases, a presenting history of chest discomfort with precordial T changes either on the admission or next-day ECG was highly sensitive and specific for this diagnosis. In some cases, type 2 myocardial infarction can also have a Wellens-like ECG phenotype without significant left anterior descending disease.

CONCLUSIONS

Precordial T wave changes in hospitalized patients have various etiologies, and in individual cases, the changes on the ECG alone cannot easily distinguish the presumptive diagnosis and additional data are required.

Cardiac magnetic resonance in the assessment of hypertrophic cardiomyopathy phenotypes and stages - pictorial review

The aim of this paper is to present recent advances in hypertrophic cardiomyopathy (HCM) diagnosis and treatment based on a literature review. Special emphasis has been placed on the role of cardiac magnetic resonance imaging (CMR) for the assessment of morphological and functional consequences of different stages of HCM including prognostication. The text is illustrated with the images and data of the HCM patients diagnosed with CMR study in our hospital. CMR is an important tool, particularly relevant in novel risk factors and LV dysfunction groups. The HCM group with overt left ventricular dysfunction is underrecognized, often labelled by clinicians as dilated cardiomyopathy. Advanced diagnostic and management strategies effectively influence the natural history of HCM.

Beware of regression of electrocardiographic abnormalities on detraining - It may not always mean 'athlete's heart'

Hypertrophic cardiomyopathy is one of the main causes of sudden cardiac death in young athletes. Differentiating between this pathological condition and 'athlete's heart' can be quite challenging, warranting a thorough clinical and imaging assessment. Clinicians often rely on detraining-induced attenuation of electrocardiographic and echocardiographic findings as a means of distinguishing between pathological and physiological cardiac remodeling. This report describes detraining-related regression of left ventricular hypertrophy in a young soccer player with a diagnosis of hypertrophic cardiomyopathy. It challenges the dogma that regression of electrocardiographic abnormalities and left ventricular hypertrophy is exclusive to physiological remodeling and questions the impact of exercise training in the phenotypic expression and progression of hypertrophic cardiomyopathy.

Cardiac magnetic resonance in the diagnosis of the unusually detected acute myocarditis in the young people: a case report

Myocarditis is among the causes of arrhythmic sudden cardiac death (SCD) in young athletes, with viral infection being the most common cause worldwide. Myocarditis recently has been reported as one of the cardiac complications of coronavirus disease 2019 (COVID-19) in athletes. Here we present a case of a 20-year-old male recreational soccer player with an episode of loss of consciousness in the context of respiratory infection. The patient reports having woken up with symptoms of an upper respiratory tract infection, and after playing a soccer match, he developed dizziness and a headache. He then suffered vasovagal syncope without loss of sphincter control. Physical examination, heart auscultation, peripheral and carotid pulses, and blood, microbiological/serological tests result on admission were normal. Moreover, no jugular engorgement at 45º, malleolar edema, or other heart failure signs were found. The 12-lead electrocardiogram (ECG), echocardiogram, 24-hour Holter-ECG did not reveal any significant finding. A cardiac magnetic resonance (CMR) was finally performed, revealing an abnormal signal increase was observed at the apical level in the short-tau inversion-recovery (STIR) and 4-chamber sequences. In addition, a pattern of apical fibrosis was observed in 4- and 2-chamber and short-axis late enhancement sequences for assessment of myocardial viability confirming the diagnosis of myocarditis. In athletes with suspected myocarditis, CMR seems to be a useful diagnostic tool, with excellent sensitivity for detecting inflammation, myocardial edema, and/or focal scarring.

Exercise-Induced Cardiovascular Adaptations and Approach to Exercise and Cardiovascular Disease: JACC State-of-the-Art Review

The role of the sports cardiologist has evolved into an essential component of the medical care of athletes. In addition to the improvement in health outcomes caused by reductions in cardiovascular risk, exercise results in adaptations in cardiovascular structure and function, termed exercise-induced cardiac remodeling. As diagnostic modalities have evolved over the last century, we have learned much about the healthy athletic adaptation that occurs with exercise. Sports cardiologists care for those with known or previously unknown cardiovascular conditions, distinguish findings on testing as physiological adaptation or pathological changes, and provide evidence-based and "best judgment" assessment of the risks of sports participation. We review the effects of exercise on the heart, the approach to common clinical scenarios in sports cardiology, and the importance of a patient/athlete-centered, shared decision-making approach in the care provided to athletes.

Beware of regression of electrocardiographic abnormalities on detraining - It may not always mean 'athlete's heart'

Hypertrophic cardiomyopathy is one of the main causes of sudden cardiac death in young athletes. Differentiating between this pathological condition and 'athlete's heart' can be quite challenging, warranting a thorough clinical and imaging assessment. Clinicians often rely on detraining-induced attenuation of electrocardiographic and echocardiographic findings as a means of distinguishing between pathological and physiological cardiac remodeling. This report describes detraining-related regression of left ventricular hypertrophy in a young soccer player with a diagnosis of hypertrophic cardiomyopathy. It challenges the dogma that regression of electrocardiographic abnormalities and left ventricular hypertrophy is exclusive to physiological remodeling and questions the impact of exercise training in the phenotypic expression and progression of hypertrophic cardiomyopathy.

Hypertrophic Cardiomyopathy: Updates Through the Lens of Sports Cardiology

Purpose of review

This review will summarize the distinction between hypertrophic cardiomyopathy (HCM) and exercise-induced cardiac remodeling (EICR), describe treatments of particular relevance to athletes with HCM, and highlight the evolution of recommendations for exercise and competitive sport participation relevant to individuals with HCM.

Recent findings

Whereas prior guidelines have excluded individuals with HCM from more than mild-intensity exercise, recent data show that moderate-intensity exercise improves functional capacity and indices of cardiac function and continuation of competitive sports may not be associated with worse outcomes. Moreover, recent studies of athletes with implantable cardioverter defibrillators (ICDs) demonstrated a safer profile than previously understood. In this context, the updated American Heart Association/American College of Cardiology (AHA/ACC) and European Society of Cardiology (ESC) HCM guidelines have increased focus on shared decision-making and liberalized restrictions on exercise and sport participation among individuals with HCM.

Summary

New data demonstrating the safety of exercise in individuals with HCM and in athletes with ICDs, in addition to a focus on shared decision-making, have led to the most updated guidelines easing restrictions on exercise and competitive athletics in this population. Further athlete-specific studies of HCM, especially in the context of emerging therapies such as mavacamten, are important to inform accurate risk stratification and eligibility recommendations.

Exercise in hypertrophic cardiomyopathy: restrict or rethink

The detailed physiological consequences of aerobic training, in patients with hypertrophic cardiomyopathy (HCM), are not well understood. In athletes and nonathletes with HCM, there are two hypothetical concerns with respect to exercise: exercise-related worsening of the phenotype (e.g., promoting hypertrophy and fibrosis) and/or triggering of arrhythmia. The former concern is unproven and animal studies suggest an opposite effect, where exercise has been shown to be protective. The main reason for exercise restriction in HCM is fear of exercise-induced arrhythmia. Although the safety of sports in HCM has been reviewed, even more recent data suggest a substantially lower risk for sudden cardiac death (SCD) in HCM than previously thought, and there is an ongoing debate about restrictions of exercise imposed on individuals with HCM. This review outlines the pathophysiology of HCM, the impact of acute and chronic exercise (and variations of exercise intensity, modality, and athletic phenotype) in HCM including changes in autonomic function, blood pressure, cardiac dimensions and function, and cardiac output, and the underlying mechanisms that may trigger exercise-induced lethal arrhythmias. It provides a critical evaluation of the evidence regarding risk of SCD in athletes and the potential benefits of targeted exercise prescription in adults with HCM. Finally, it provides considerations for personalized recommendations for sports participation based on the available data.

Cardiac Structure and Function in Elite Female and Male Soccer Players

Importance

Population-specific normative data are essential for the evaluation of competitive athletes. At present, there are limited data defining normal electrocardiographic (ECG) and echocardiographic values among elite US soccer players.

Objective

To describe ECG and echocardiographic findings in healthy elite US soccer players.

Design, Setting, and Participants

This cross-sectional study analyzed Fédération Internationale de Football Association-mandated screening sessions performed at US Soccer National Team training locations from January 2015 to December 2019. US women's and men's national team soccer players undergoing mandated cardiovascular screening were included.

Main Outcomes and Measures

Normal training-related and abnormal ECG findings were reported using the International Recommendations for Electrocardiographic Interpretation in Athletes. Echocardiographic measurements of structural and functional parameters relevant to cardiovascular remodeling were assessed relative to American Society of Echocardiography guideline-defined normal ranges.

Results

A total of 238 athletes (122 [51%] female; mean [SD] age, 20 [4] years; age range, 15-40 years) were included. Male athletes demonstrated a higher prevalence of normal training-related ECG findings, while female athletes were more likely to have abnormal ECG patterns (14 [11%] vs 0 in male cohort), largely accounted for by abnormal T-wave inversions. Echocardiography revealed no pathologic findings meeting criteria for sport restriction, but athletes frequently exceeded normal ranges for structural cardiac parameters responsive to exercise-induced remodeling including body surface area-indexed left ventricular (LV) mass (58 of 113 female athletes [51%] and 67 of 114 male athletes [59%]), indexed LV volume (89 of 115 female athletes [77%] and 76 of 111 male athletes [68%]), and LV wall thickness (37 of 122 female athletes [30%] and 47 of 116 male athletes [41%]). Age-stratified analysis revealed age-dependent increases in LV wall thickness, mass, and volumes among female athletes and LV wall thickness and mass among male athletes.

Conclusions and Relevance

These data represent the first set of comprehensive normative values for elite US soccer players and one of the largest sport-specific echocardiographic remodeling studies in female athletes. Abnormal ECG findings were more common in female athletes, while both female and male athletes frequently exceeded clinical normality cut points for remodeling-associated echocardiographic parameters.

Aortic dilatation: Value of echocardiography in the systematic assessment of elite rugby players in the French National Rugby League (LNR)

The value of echocardiography in the screening of athletes in addition to the electrocardiogram is debated and still unclear. 336 rugby players in French professional divisions (Top 14, Pro D2) were prospectively assessed with electrocardiogram and echocardiography. 75% were Caucasian, 16.4% Pacific Islanders, and 8.6% Afro-Caribbean. Six (1.8%) players had electrocardiogram abnormalities, exclusively negative T waves. Twenty-one (6.25%) of them had abnormal echocardiography findings: one possible early hypertrophic cardiomyopathy, one anomalous origin of coronary artery, two left ventricular dilatations, one isolated bicuspid aortic valve, two aortic regurgitations, and 14 ascending aortic dilatations. The median aortic diameter was modestly correlated with age: 32 mm [23-48] in players aged ≤25 years vs 33.5 mm [24-50] in those aged >25 years (P = 0.02, correlation coefficient -.01). This tendency increased with cumulative hours of weight training: 34 mm [24-50] in forwards vs 32 mm [25-44] in backs (P = 0.01); and ethnicity, with Pacific Islanders having higher values in both raw data and body surface area or height-indexed data than Afro-Caribbeans and Caucasians: 34 [25-50] vs 32 [27-48] and 33 [23-49] mm (P = 0.017); 15 [12.2-21] vs 14.8 [11-19.9] and 14.8 [10-20.9] mm/m² (P < 0.0001); 18.5 [14-25] mm/m vs 17.4 [14.8-25] mm/m and 17.6 [12.2-25.3] mm/m (P = 0.0125). In a population of professional rugby players, echocardiography was contributive. The main anomaly was aortic dilatation (14/336, 4.2%). While this is proportionally much higher than in other sports, the cutoffs need to be defined more precisely by including the criterion of ethnicity, as is already the case for electrocardiography.

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.

Prevalence of Unexplained Left Ventricular Hypertrophy by Cardiac Magnetic Resonance Imaging in MESA

Background

Hypertrophic cardiomyopathy is defined as unexplained left ventricular (LV) hypertrophy (wall thickness ≥15 mm) and is prevalent in 0.2% of adults (1:500) in population‐based studies using echocardiography. Cardiac magnetic resonance imaging (MRI) allows for more accurate wall thickness measurement across the entire ventricle than echocardiography. The prevalence of unexplained LV hypertrophy by cardiac MRI is unknown. MESA (Multi‐Ethnic Study of Atherosclerosis) recruited individuals without overt cardiovascular disease 45 to 84 years of age.

Methods and Results

We studied 4972 individuals who underwent measurement of regional LV wall thickness by cardiac MRI as part of the MESA baseline exam. American Heart Association criteria were used to define LV segments. We excluded participants with hypertension, LV dilation (≥95% predicted end‐diastolic volume) or dysfunction (ejection fraction ≤50%), moderate‐to‐severe left‐sided valve lesions by cardiac MRI, severe aortic valve calcification by cardiac computed tomography (aortic valve Agatston calcium score >1200 in women or >2000 in men), obesity (body mass index >35 kg/m²), diabetes mellitus, and current smoking. Sixty‐seven participants (aged 64±10 years, 9% female) had unexplained LV hypertrophy (wall thickness ≥15 mm in at least 2 adjacent LV segments), representing 1.4% (1 in 74) participants, 2.6% of men and 0.2% of women. Prevalence was similar across categories of race/ethnicity. Hypertrophy was focal in 17 (25.4%), intermediate in 44 (65.7%), and diffuse in 5 (7.5%) participants.

Conclusions

The prevalence of unexplained LV hypertrophy in a population‐based cohort using cardiac MRI was 1.4%. This may have implications for the diagnosis of patients with hypertrophic cardiomyopathy and will require further study.

Inferolateral T wave inversion in athletes: phenotype-genotype correlation

AIMS

Significant T wave inversion in young asymptomatic athletes is rare but poses a significant clinical challenge. Pre-participation sports screening programs identify such subjects. Clinical concern that such ECG changes represent an occult cardiomyopathy or forme fruste hypertrophic cardiomyopathy leads to diagnostic and therapeutic dilemma. We sought to genotype a cohort of such subjects with a normal cardiac phenotype identified in our unit over a 3-year period.

METHODS

Ten athletes were referred from external screening. All exhibited deep T wave inversion inferolaterally. All had negative family history for sudden death and had a normal phenotype. A panel of 133 cardiac genes were screened.

RESULTS

Ten male subjects with mean age of 39 years were screened. Seven had no evidence of mutations. Three subjects demonstrated variants of uncertain significance in 5 different genes: alpha-2-actinin (ACTN2), myopalladin (MYPN), the calcium channel genes CACNA1C and TRPM4 and potassium channel gene KCNQ1. The variants found have not been described in cardiomyopathies or channelopathies. At 3-year follow-up, one patient had undergone detraining, and his ECG showed complete resolution of all T wave changes. He did not have any demonstrated variants.

CONCLUSIONS

The absence of mutations in target genes and heterogeneous sequence variations identified in this study suggest that inferolateral T wave inversion in athletes without a phenotype may potentially represent a benign repolarization syndrome related to athletic adaptation. This was the first study to assess a phenotype-genotype correlation in this population. Further genetic studies need to be undertaken in this area.

Interpretation of T-wave inversion in physiological and pathological conditions: Current state and future perspectives

The presence of T‐wave inversion (TWI) at 12‐lead electrocardiogram (ECG) in competitive athletes is one of the major diagnostic challenges for sports physicians and consulting cardiologists. Indeed, while the presence of TWI may be associated with some benign conditions and it may be occasionally seen in healthy athletes presenting signs of cardiac remodeling, it may also represent an early sign of an underlying, concealed structural heart disease or life‐threatening arrhythmogenic cardiomyopathies, which may be responsible for exercise‐related sudden cardiac death (SCD). The interpretation of TWI in athletes is complex and the inherent implications for the clinical practice represent a conundrum for physicians. Accordingly, the detection of TWI should be viewed as a potential red flag on the ECG of young and apparently healthy athletes and warrants further investigations because it may represent the initial expression of cardiomyopathies that may not be evident until many years later and that may ultimately be associated with adverse outcomes. The aim of this review is, therefore, to report an update of the literature on TWI in athletes, with a specific focus on the interpretation and management.

Abnormal ECG Findings in Athletes: Clinical Evaluation and Considerations

PURPOSE OF REVIEW

Pre-participation cardiovascular evaluation with electrocardiography is normal practice for most sporting bodies. Awareness about sudden cardiac death in athletes and recognizing how screening can help identify vulnerable athletes have empowered different sporting disciplines to invest in the wellbeing of their athletes.

RECENT FINDINGS

Discerning physiological electrical alterations due to athletic training from those representing cardiac pathology may be challenging. The mode of investigation of affected athletes is dependent on the electrical anomaly and the disease(s) in question. This review will highlight specific pathological ECG patterns that warrant assessment and surveillance, together with an in-depth review of the recommended algorithm for evaluation.

Hypertrophic Cardiomyopathy–Related Sudden Cardiac Death in Young People in Ontario

Background:

Hypertrophic cardiomyopathy (HCM) is considered a leading cause of sudden cardiac death (SCD) in younger people. The incidence of HCM-related SCD and its relationship to exercise have not been well studied in large comprehensive studies outside of tertiary care settings. This study sought to estimate the incidence of HCM-related SCD and its association with exercise in a large unselected population.

Methods:

Using the Office of the Chief Coroner of Ontario database encompassing all deaths attended by the coroner, we identified all HCM-related SCDs in individuals 10 to 45 years of age between 2005 and 2016 (70 million person-years). Confirmation of HCM was based on typical macroscopic and microscopic features (definite HCM-related SCD). Sudden deaths with a prior clinical diagnosis of HCM but no autopsy were considered probable HCM-related SCDs. Cases with typical features but no myofiber disarray were considered possible HCM. The completeness of data was verified in a subset of patients in the Toronto area with the use of a registry of all emergency medical services–attended cardiac arrests, with an autopsy rate of 94%. To estimate the number of HCM-related aborted cardiac arrests and lives potentially saved by implantable cardioverter-defibrillators, all de novo implantations for secondary prevention and all implantations and appropriate shocks for primary prevention in patients with HCM 10 to 45 years of age, respectively, were identified with the use of a registry containing data on implantable cardioverter-defibrillator implantations from all implanting sites throughout Ontario.

Results:

Forty-four, 3, and 6 cases of definite, probable, and possible HCM-related SCDs, respectively, were identified, corresponding to estimated annual incidence rates of 0.31 per 1000 HCM person-years (95% CI, 0.24–0.44) for definite HCM-related SCD, 0.33 per 1000 HCM person-years (95% CI, 0.34–0.62) for definite or probable HCM-related SCD, and 0.39 per 1000 HCM person-years (95% CI, 0.28–0.49) for definite, probable, or possible HCM-related SCD (estimated 140 740 HCM person-years of observation). The estimated annual incidence rate for HCM-related SCD plus aborted cardiac arrest and HCM-related life-threatening arrhythmia (SCD, aborted cardiac arrest, and appropriate implantable cardioverter-defibrillator shocks) was 0.84 per 1000 HCM person-years (95% CI, 0.70–1.0). The majority (70%) of SCDs occurred in previously undiagnosed individuals. Most SCDs occurred during rest (64.8%) or light activity (18.5%).

Conclusions:

The incidence of HCM-related SCD in the general population 10 to 45 years of age is substantially lower than previously reported, with most cases occurring in previously undiagnosed individuals. SCDs are infrequently related to exercise.

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 26-27 February 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.

[ECG in sportsmen: Distinguishing the normal from the pathological]

An ECG is recommended by the French Society of Cardiology in the screening of a competitive athlete. An intense and prolonged physical activity (>4 hours of intense sport/week) can lead to a physiological electric remodeling. In addition to physical activity (type, intensity, duration), the ECG should be interpreted according to the athlete's ethnicity and age. It is necessary to know the physiological modifications related to sport practice to avoid either false reassurances or the realization of unjustified additional examinations because of a wrong interpretation. The latest athlete ECG classification published in 2017 can be used to identify in which athlete additional tests are recommended (figure 1).

Canadian Cardiovascular Society Cardiovascular Screening of Competitive Athletes: The Utility of the Screening Electrocardiogram to Predict Sudden Cardiac Death

Prevention of sudden cardiac arrest/death (SCA/D) among athletes is a universal goal, although the optimal strategy for its achievement is controversial, with the inclusion of the 12-lead electrocardiogram (ECG) at the center of the debate. The ECG exhibits superior sensitivity over history and physical examination to detect conditions associated with SCA/D. However, the identification of disease does not necessarily lead to a significant reduction in SCA/D. The "Canadian Cardiovascular Society/Canadian Heart Rhythm Society Joint Position Statement on the Cardiovascular Screening of Competitive Athletes" recommended against the routine performance of an ECG for the initial cardiovascular screening of competitive athletes. The incidence of SCA/D among athletes (<35 years of age), the risk of SCA/D during sport participation among individuals with abnormalities found on screening ECG, the efficacy of the ECG to identify conditions associated with SCA/D, and the positive predictive value of an abnormal ECG to predict SCA/D are critically examined. This review presents the evidence informing the panel's recommendation.

Myocarditis in Athletes Is a Challenge: Diagnosis, Risk Stratification, and Uncertainties

Presentation of myocarditis in athletes is heterogeneous and establishing the diagnosis is challenging with no current uniform clinical gold standard. The combined information from symptoms, electrocardiography, laboratory testing, echocardiography, cardiac magnetic resonance imaging, and in certain cases endomyocardial biopsy helps to establish the diagnosis. Most patients with myocarditis recover spontaneously; however, athletes may be at higher risk of adverse cardiac events. Based on scarce evidence and mainly autopsy studies and expert's opinions, current recommendations generally advise abstinence from competitive sports ranging from a minimum of 3 to 6 months. However, the dilemma poses that (un)necessary prolonged disqualification of athletes to avoid adverse cardiac events can cause considerable disruption to training schedules and tournament preparation and lead to a decline in performance and ability to compete. Therefore, better risk stratification tools are imperatively needed. Using latest available data, this review contrasts existing recommendations and presents a new proposed diagnostic flowchart putting a greater focus on the use of cardiac magnetic resonance imaging in athletes with suspected myocarditis. This may enable cardiac caregivers to counsel athletes with suspected myocarditis more systematically and furthermore allow for pooling of more unified data. To modify recommendations regarding sports behavior in athletes with myocarditis, evidence, based on large multicenter registries including cardiac magnetic resonance imaging and endomyocardial biopsy, is needed. In the future, physicians might rely on combined novel risk stratification methods, by implementing both noninvasive and invasive tissue characterization methods.

Pre-participation cardiovascular evaluation in Pacific Island athletes

BACKGROUND

Pre-participation cardiovascular evaluation (PPE) aims to detect cardiac disease with sudden cardiac death (SCD) risk. No study has focused on Pacific Island athletes.

METHODS

A total of 2281 Pacific Island athletes were studied with (i) a questionnaire on family, personal history and symptoms, (ii) a physical examination and (iii) a 12-lead ECG.

RESULTS

85% presented a normal history and examination. A positive family history was 1.4-1.9 fold higher in Melanesians, Polynesians and Métis than in Caucasians, while a positive personal history, abnormal symptoms and abnormal examination was 1.3 fold higher in Melanesians and Métis than in others. Neither gender nor training level had a bearing on these results. Melanesians had higher T wave inversions (TWIs) in V2-V4 leads but had no CV abnormalities. Lateral or infero-lateral TWIs were found in 6 male and in 5 highly trained athletes and cardiomyopathies were diagnosed in 3/6 athletes. Overall, 3.9% athletes were found to have a CV abnormality and 0.8% had a risk of SCD. Polynesians and males were more at risk than the others while the level of training made no difference. In athletes at risk of SCD, the main detected CV diseases were cardiomyopathies, Wolff-Parkinson-White (WPW) and severe valve lesions of rheumatoid origin.

CONCLUSIONS

PPE revealed that 3.9% presented CV abnormalities. A risk of SCD was found in 0.8% with cardiomyopathies, WPW, and severe valve lesions of rheumatoid origin. Melanesians, Polynesians and male of high level of training were more at risk than others.

Left Ventricular Hypertrophy in Athletes: Differentiating Physiology From Pathology

PURPOSE OF REVIEW

The changes that occur in athlete's heart are influenced by a number of factors including age, gender, ethnicity and the type of cardiovascular training. It is therefore important that the clinician is able to integrate all of these factors when assessing athletes to be able to guide investigations appropriately and to distinguish pathology from physiology. This review discusses the potential diagnostic conundrums when trying to differentiate physiological left ventricular hypertrophy from pathological hypertrophic cardiomyopathy in athletes. The mechanism of physiological and pathological hypertrophy is discussed together with history, clinical and investigational findings that can help to identify pathology.

RECENT FINDINGS

Athletes with hypertrophic cardiomyopathy are more likely to have non-concentric left ventricular hypertrophy (LVH), an elevated relative wall thickness, lateral ECG changes and a smaller LV cavity than athletes with physiological LVH. Certain diastolic echocardiographic parameters when used as part of an algorithm (e'; E/E'; E/A) can help to distinguish physiology from pathology, and there is evidence that assessment of global longitudinal strain during exercise echocardiography may be of use in the future. Cardiac MRI is an important imaging modality that can have an additive effect over echocardiography in the diagnosis of cardiomyopathy. Late gadolinium enhancement is a recognised advantage for cardiac magnetic resonance to allow detection of fibrosis in hypertrophic cardiomyopathy. T1 mapping and extracellular volume quantification may be a tool for the future to help distinguish athlete's heart from HCM. Cardiac adaptation to exercise and training in athletes, the athlete's heart causes electrophysiological and geometric changes that may mimic mild phenotypes of a pathological cardiomyopathy. This review article summarises a systematic approach to the assessment of left ventricular hypertrophy in athletes and describes pertinent clinical and investigation findings that can help to differentiate physiology from pathology.

Diagnostic Yield of Genetic Testing in Young Athletes With T-Wave Inversion

BACKGROUND

T-wave inversion (TWI) is common in patients with cardiomyopathy. However, up to 25% of athletes of African/Afro-Caribbean descent (black athletes) and 5% of white athletes also have TWI of unclear clinical significance despite comprehensive clinical evaluation and long-term follow-up. The aim of this study was to determine the diagnostic yield from genetic testing, beyond clinical evaluation, when investigating athletes with TWI.

METHODS

We investigated 50 consecutive asymptomatic black and 50 white athletes 14 to 35 years of age with TWI and a normal echocardiogram who were referred to a UK tertiary center for cardiomyopathy and sports cardiology. Subjects underwent exercise testing, 24-hour ambulatory ECG, signal-averaged ECG, cardiac magnetic resonance imaging, and a blood-based analysis of a comprehensive 311-gene panel for cardiomyopathies and ion channel disorders associated with TWI, including hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, dilated cardiomyopathy, left ventricular noncompaction, long-QT syndrome, and Brugada syndrome.

RESULTS

In total, 21 athletes (21%) were diagnosed with cardiac disease on the basis of comprehensive clinical investigations. Of these, 8 (38.1%) were gene positive (myosin binding protein C[ MYBPC3], myosin heavy chain 7 [ MYH7], galactosidase alpha [ GLA], and actin alpha, cardiac muscle 1 [ ACTC1] genes) and 13 (61.9%) were gene negative. Of the remaining 79 athletes (79%), 2 (2.5%) were gene positive (transthyretin [ TTR] and sodium voltage-gated channel alpha subunit 5 [ SCN5A] genes) in the absence of a clinical phenotype. The prevalence of newly diagnosed cardiomyopathy was higher in white athletes compared with black athletes (30.0% versus 12%; P=0.027). Hypertrophic cardiomyopathy accounted for 90.5% of all clinical diagnoses. All black athletes and 93.3% of white athletes with a clinical diagnosis of cardiomyopathy or a genetic mutation capable of causing cardiomyopathy exhibited lateral TWI as opposed to isolated anterior or inferior TWI; the genetic yield of diagnoses from lateral TWI was 12.3%.

CONCLUSIONS

Up to 10% of athletes with TWI revealed mutations capable of causing cardiac disease. Despite the substantial cost, the positive diagnostic yield from genetic testing was one half that from clinical evaluation (10% versus 21%) and contributed to additional diagnoses in only 2.5% of athletes with TWI in the absence of a clear clinical phenotype, making it of negligible use in routine clinical practice.

Electrocardiography in athletes: normal and abnormal findings

Many sporting organisations recommend a pre-participation ECG to screen for disorders which predispose to sudden cardiac arrest (SCA). The ability of the ECG to perform accurately is dependent on the ECG criteria used and the experience of the operator. There have been several ECG criteria over the last decade, though these were recently superseded with the publication of the 'International Consensus Criteria for ECG Interpretation in Athletes'. These criteria use the latest evidence to improve specificity while maintaining sensitivity for ECG-detectable pathologies associated with SCA. Accordingly, this review describes the normal, borderline and abnormal ECG findings in an asymptomatic athlete aged 12-35 years.

Pediatric Electrocardiograms for the General Practitioner: The Importance of the T-Wave

Electrocardiograms may be used to screen for cardiovascular disease (CVD) in children. Many forms of CVD that predispose to sudden cardiac death are associated with T-wave abnormalities in childhood. The T-wave is generated during ventricular repolarization. T-waves on an electrocardiogram typically undergo maturational changes throughout childhood and adolescence. A pediatric practitioner's ability to understand these changes is required to understand abnormal T-waves and recognize potentially life-threatening types of CVD. This review article uses a series of illustrative cases to highlight CVD associated with T-wave abnormalities in childhood. [Pediatr Ann. 2018;47(3):e106-e111.].

The congenital long QT syndrome Type 3: An update

Congenital long QT syndrome type 3 (LQT3) is the third in frequency compared to the 15 forms known currently of congenital long QT syndrome (LQTS). Cardiac events are less frequent in LQT3 when compared with LQT1 and LQT2, but more likely to be lethal; the likelihood of dying during a cardiac event is 20% in families with an LQT3 mutation and 4% with either an LQT1 or an LQT2 mutation. LQT3 is consequence of mutation of gene SCN5A which codes for the Nav1.5 Na+ channel α-subunit and electrocardiographically characterized by a tendency to bradycardia related to age, prolonged QT/QTc interval (mean QTc value 478 ± 52 ms), accentuated QT dispersion consequence of prolonged ST segment, late onset of T wave and frequent prominent U wave because of longer repolarization of the M cell across left ventricular wall.