Value of screening for the risk of sudden cardiac death in young competitive athletes.

AIMS: This study aimed to report the long-term findings of the Italian programme of cardiovascular preparticipation screening (PPS) in young, competitive athletes. METHODS AND RESULTS: The study assessed the diagnostic yield for diseases at risk of sudden cardiac death (SCD), the costs of serial evaluations, and the long-term outcomes of PPS in a large population of Italian children (age range, 7-18 years). The PPS was repeated annually and included medical history, physical examination, resting electrocardiogram, and stress testing; additional tests were reserved for athletes with abnormal findings. Over an 11-year study period, 22 324 consecutive children [62% males; mean age, 12 (interquartile range, 10-14) years at first screening] underwent a total of 65 397 annual evaluations (median 2.9/child). Cardiovascular diseases at risk of SCD were identified in 69 children (0.3%) and included congenital heart diseases (n = 17), channelopathies (n = 14), cardiomyopathies (n = 15), non-ischaemic left ventricular scar with ventricular arrhythmias (n = 18), and others (n = 5). At-risk cardiovascular diseases were identified over the entire age range and more frequently in children ≥12 years old (n = 63, 91%) and on repeat evaluation (n = 44, 64%). The estimated cost per diagnosis was 73 312€. During a follow-up of 7.5 ± 3.7 years, one child with normal PPS findings experienced an episode of resuscitated cardiac arrest during sports activity (event rate of 0.6/100.000 athletes/year). CONCLUSION: The PPS programme led to the identification of cardiovascular diseases at risk of SCD over the whole study age range of children and more often on repeat evaluations. Among screened children, the incidence of sport-related cardiac arrest during long-term follow-up was low.

Prevalence and clinical significance of isolated low QRS voltages in young athletes.

AIMS: Low QRS voltages (peak to peak <0.5 mV) in limb leads (LQRSV) on the athlete's electrocardiogram (ECG) may reflect an underlying cardiomyopathy, mostly arrhythmogenic cardiomyopathy (ACM) or non-ischaemic left ventricular scar (NILVS). We studied the prevalence and clinical meaning of isolated LQRSV in a large cohort of competitive athletes. METHODS AND RESULTS: The index group included 2229 Italian competitive athletes [median age 18 years (16-25), 67% males, 97% Caucasian] without major ECG abnormalities at pre-participation screening. Three control groups included Black athletes (N = 1115), general population (N = 1115), and patients with ACM or NILVS (N = 58). Echocardiogram was performed in all athletes with isolated LQRSV and cardiac magnetic resonance (CMR) in those with ventricular arrhythmias or echocardiographic abnormalities. The isolated LQRSV pattern was found in 1.1% index athletes and was associated with increasing age (median age 28 vs. 18 years; P < 0.001), elite status (71% vs. 34%; P < 0.001), body surface area, and body mass index but not with sex, type of sport, and echocardiographic left ventricular mass. The prevalence of isolated LQRSV was 0.2% in Black athletes and 0.3% in young individuals from the general population. Cardiomyopathy patients had a significantly greater prevalence of isolated LQRSV (12%) than index athletes, Black athletes, and general population. Five index athletes with isolated LQSRV and exercise-induced ventricular arrhythmias underwent CMR showing biventricular ACM in 1 and idiopathic NILVS in 1. CONCLUSIONS: Unlike cardiomyopathy patients, the ECG pattern of isolated LQRSV was rarely observed in athletes. This ECG sign should prompt clinical work-up for exclusion of an underlying cardiomyopathy.

Exercise-Based Cardiac Rehabilitation Programs in Heart Failure Patients.

Exercise training is recommended for patients with heart failure by major societies' guidelines. It improves exercise capacity and quality of life, reduces symptoms of depression, can improve survival, and reduce the risk for hospitalizations. Exercise-based cardiac rehabilitation can be offered with different modalities, such as continuous or interval aerobic training, resistance, and inspiratory muscle training. The intervention must follow an accurate evaluation of the patient's cardiovascular conditions and functional capacity. Despite the multiple benefits of exercise training, there is a lack of adherence to exercise-based programs, due to socioeconomic factors, patients' characteristics, and lack of referral.

The Italian preparticipation evaluation programme: diagnostic yield, rate of disqualification and cost analysis.

INTRODUCTION: Italian law mandates that every competitive athlete must undergo annual preparticipation evaluation (PPE) to identify cardiovascular (CV) diseases that pose a risk of sudden death (SD) during sport and other conditions that may threaten the athlete's health. We investigated the diagnostic yield, rate of disqualification and costs of our PPE. METHODS: We included 5910 consecutive apparently healthy athletes (61% males, mean age 15±4 years) who underwent annual PPE performed by a sports medicine specialist. The PPE included history, physical examination, weight, height and blood pressure measurement, test of visual acuity, spirometry, urine chemistry, resting 12-lead ECG and exercise testing with ECG monitoring. In cases of abnormal findings, we carried out second-line investigations. RESULTS: During a 12-month study period, 5.326 (90.2%) athletes were cleared for competition after a normal first-line evaluation and 584 (9.8%) underwent one or more further examinations. Of those, 88 (1.5%) were diagnosed to have a CV disease (including 18 (0.3%) at-risk of SD) and 31 (0.5%) had a non-CV diagnosis. A total of 32 (0.5%) athletes were temporarily (n=15) or permanently (n=17) disqualified from competitive sports. The average cost per athlete was €79, which consisted of €64 (80%) for first-line evaluations and €15 (20%) for additional investigations. CONCLUSION: PPE according to the Italian model identified a range of diseases in 2.0% of apparently healthy athletes at an average cost of €79.

Characteristics of structured physical training currently provided in cardiac patients: insights from the Exercise Training in Cardiac Rehabilitation (ETCR) Italian survey.

BACKGROUND: Uncertainty exists about current delivery levels of exercise training (ET) during Cardiac Rehabilitation (CR) programmes. AIM OF THE STUDY: To evaluate ET modalities in the real world of CR facilities in Italy. METHODS: This was an observational survey of aggregate data, collected from CR facilities on a voluntary basis. Snapshots of a single working day at a local site were made, in terms of characteristics of patients and ET programmes delivered. RESULTS. Overall, 612 patients from 26 CR units were included, with an in-patient vs. out-patient ratio of 3:1. Coronary artery disease (57.6%), heart failure (20.3%), and valve disease/surgery (22.1%) were the most represented target groups. The prevalence of endurance continuous training, interval training, and resistance/strength training was 66.7%, 11.1%, and 9.0%; other non-aerobic endurance and non-resistance training modalities such as respiratory muscle training and calisthenics were reported in 39.9% and 42.9% of cases respectively. Workloads for endurance exercise training were determined by cardiopulmonary test, conventional 12-leads ECG exercise testing, 6min-walking test, theoretical determination of heart rate, and rating of perceived exertion in 9%, 8%, 27%, 9%, and 40% of cases respectively. The average duration of the programmes (on an intention to treat basis) was 25 sessions of 42±11  minutes, with a frequency of >4 sessions/week in 67% of patients. CONCLUSIONS: Despite advances in CR interventions, there is a significant need for improvement of functional evaluation and exercise training prescription, and consideration of a wider range of training modalities in Italy. .

Physical activity in solid organ transplant recipients: preliminary results of the Italian project.

BACKGROUND/AIMS: The role of physical activity in transplanted patients is often underestimated. We discuss the Italian National Transplant Centre experience, which started in 2008 studying transplanted patients involved in sports activities. The study was then developed through a model of cooperation between surgeons, sports physicians and exercise specialists. METHODS: A multicentre study was realized in 120 transplanted patients of which 60 treated with supervised physical activity (three sessions/week of aerobic and strengthening exercises) and 60 controls. We present the results of the first 26 patients (16 males, 10 females; 47.8 ± 10.0 years; 21 kidney, 5 liver transplanted; time from transplant 2.3 ± 1.4 years) who completed 12 months of supervised physical activity. RESULTS: Data showed an increase of peak aerobic power (t=4.535; P<0.01) and maximum workload (t=4.665; P<0.01) in the incremental cycling test. Maximum strength of knee extensors (t=2.933; P<0.05) and elbow flexors (t=2.450; P<0.05), and the power of lower limb (t=2.303; P<0.05) significantly increases. Health Related Quality of Life showed a significant improvement. Serum creatinine (1.4 ± 0.5 vs 1.3 ± 0.4 mg/dL) and proteinuria (0.10 ± 0.14 vs 0.08 ± 0.08 gr/dL) were stable. CONCLUSION: These preliminary results confirm the positive effects of supervised physical exercise. It can be considered as an input to promote other detailed exercise protocols.

First report from the European registry for anomalous aortic origin of coronary artery (EURO-AAOCA).

OBJECTIVES: Anomalous aortic origin of a coronary artery (AAOCA) is a group of rare congenital heart defects with various clinical presentations. The lifetime-risk of an individual living with AAOCA is unknown, and data from multicentre registries are urgently needed to adapt current recommendations and guide optimal patient management. The European AAOCA Registry (EURO-AAOCA) aims to assess differences with regard to AAOCA management between centres. METHODS: EURO-AAOCA is a prospective, multicentre registry including 13 European centres. Herein, we evaluated differences in clinical presentations and management, treatment decisions and surgical outcomes across centres from January 2019 to June 2023. RESULTS: A total of 262 AAOCA patients were included, with a median age of 33 years (12-53) with a bimodal distribution. One hundred thirty-nine (53.1%) were symptomatic, whereas chest pain (n = 74, 53.2%) was the most common complaint, followed by syncope (n = 21, 15.1%). Seven (5%) patients presented with a myocardial infarction, 2 (1.4%) with aborted sudden cardiac death. Right-AAOCA was most frequent (150, 57.5%), followed by left-AAOCA in 51 (19.5%), and circumflex AAOCA in 20 (7.7%). There were significant differences regarding diagnostics between age groups and across centres. Seventy-four (28.2%) patients underwent surgery with no operative deaths; minor postoperative complications occurred in 10 (3.8%) cases. CONCLUSIONS: Currently, no uniform agreement exists among European centres with regard to diagnostic protocols and clinical management for AAOCA variants. Although surgery is a safe procedure in AAOCA, future longitudinal outcome data will hopefully shed light on how to best decide towards optimal selection of patients undergoing revascularization versus conservative treatment.

Interpretation and management of premature ventricular beats in athletes: An expert opinion document of the Italian Society of Sports Cardiology (SICSPORT).

Premature ventricular beats (PVBs) are recorded in a sizeable proportion of athletes during pre-participation screening, especially if the evaluation includes both resting and exercise ECG. While in the majority of cases no underlying heart disease is present, in others PVBs may be the sign of a condition at risk of sudden cardiac death, including cardiomyopathies, congenital, coronary artery, heart valves and ion channels diseases. In this expert opinion document of the Italian Society of Sports Cardiology, we propose a multiparametric interpretation approach to PVBs in athletes and a stepwise diagnostic algorithm. The clinical work-up should include the assessment of the probable site of origin based on the ECG pattern of the ectopic QRS and of the arrhythmia behavior (including the number of different PVB morphologies, complexity, response to exercise and reproducibility), as well as first-line tests such as echocardiography. Based on this initial evaluation, most athletes can be reassured of the benign nature of PVBs and cleared for competition under periodical follow-up. However, when the clinical suspicion is high, further investigations with non-invasive (e.g. cardiac magnetic resonance, cardiac computed tomography, genetic testing) and, in very selected cases, invasive (e.g. endocardial voltage mapping and endomyocardial biopsy) tests should be carried out to rule out a high-risk condition. Importantly, such advanced tests should be performed in centers with a consolidated experience not only in the technique, but also in evaluation of athletes.

Electroanatomic mapping in athletes: Why and when. An expert opinion paper from the Italian Society of Sports Cardiology.

Three-dimensional electroanatomical mapping (EAM) has the potential to identify the pathological substrate underlying ventricular arrhythmias (VAs) in different clinical settings by detecting myocardial areas with abnormally low voltages, which reflect the presence of different cardiomyopathic substrates. In athletes, the added value of EAM may be to enhance the efficacy of third-level diagnostic tests and cardiac magnetic resonance (CMR) in detecting concealed arrhythmogenic cardiomyopathies. Additional benefits of EAM in the athlete include the potential impact on disease risk stratification and the consequent implications for eligibility to competitive sports. This opinion paper of the Italian Society of Sports Cardiology aims to guide general sports medicine physicians and cardiologists on the clinical decision when to eventually perform an EAM study in the athlete, highlighting strengths and weaknesses for each cardiovascular disease at risk of sudden cardiac death during sport. The importance of early (preclinical) diagnosis to prevent the negative effects of exercise on phenotypic expression, disease progression, and worsening of the arrhythmogenic substrate is also addressed.

Molecular genetic testing in athletes: Why and when a position statement from the Italian Society of Sports Cardiology.

Molecular genetic testing is an increasingly available test to support the clinical diagnosis of inherited cardiovascular diseases through identification of pathogenic gene variants and to make a preclinical genetic diagnosis among proband's family members (so-called "cascade family screening"). In athletes, the added value of molecular genetic testing is to assist in discriminating between physiological adaptive changes of the athlete's heart and inherited cardiovascular diseases, in the presence of overlapping phenotypic features such as ECG changes, imaging abnormalities or arrhythmias ("grey zone"). Additional benefits of molecular genetic testing in the athlete include the potential impact on the disease risk stratification and the implications for eligibility to competitive sports. This position statement of the Italian Society of Sports Cardiology aims to guide general sports medical physicians and sports cardiologists on clinical decision as why and when to perform a molecular genetic testing in the athlete, highlighting strengths and weaknesses for each inherited cardiovascular disease at-risk of sudden cardiac death during sport. The importance of early (preclinical) diagnosis to prevent the negative effects of exercise on phenotypic expression, disease progression and worsening of the arrhythmogenic substrate is also addressed.

A prospective study on the consequences of SARS-CoV-2 infection on the heart of young adult competitive athletes: Implications for a safe return-to-play.

OBJECTIVES: The COVID-19 pandemic has shocked the sports world because of the suspension of competitions and the spread of SARS-CoV-2 among athletes. After SARS-CoV-2 infection, cardio-pulmonary complications can occur and, before the resumption of sports competitions, a screening has been recommended. However, few data are available and discrepancies exist in the screening modalities. We conducted this prospective study to investigate the incidence of cardiovascular consequences following SARS-CoV-2 infection in young adult competitive athletes and the appropriate screening strategies for a safe return-to-play. METHODS: Ninety competitive athletes (24 ± 10 years) after asymptomatic or mildly symptomatic SARS-CoV-2 infection were screened by physical examination, blood testing, spirometry, 12­lead resting ECG, 24-h ambulatory ECG monitoring, echocardiogram, and cardiopulmonary exercise testing (CPET). RESULTS: Sixty-four athletes (71.1%) were male, and most (76.7%) were mildly symptomatic. After SARS-CoV-2 infection, spirometry and resting ECG were normal in all athletes. Ambulatory ECG monitoring demonstrated <50/24 h supraventricular and ventricular premature beats in 53.3% and 52.2% of athletes, respectively, in the absence of malignant arrhythmias. CPET did not demonstrate cardiopulmonary limitations. Echocardiography showed pericardial effusion in 3 athletes (all females) with symptomatic SARS-CoV-2 infection (3.3%; 4.4% in the symptomatic group) with a definitive diagnosis of myopericarditis in 1 athlete (1.1%) and pericarditis in 2 athletes (2.2%). CONCLUSIONS: Cardiac consequences of SARS-CoV-2 infection were found in 3.3% of competitive athletes. An appropriate screening primarily based on the detection of uncommon arrhythmias and cardiac symptoms should be recommended in competitive athletes after SARS-CoV-2 infection to detect a cardiac involvement and guarantee a safe return-to-play.

Papillary Muscles Abnormalities in Athletes With Otherwise Unexplained T-Wave Inversion in the ECG Lateral Leads.

Background Papillary muscles (PMs) abnormalities may be associated with ECG repolarization abnormalities. We aimed to evaluate the relation between lateral T-wave inversion (TWI) and PMs characteristics in a cohort of athletes with no clinically demonstrable cardiac disease. Methods and Results We included 53 athletes (median age, 20 years; 87% men) with lateral TWI and no evidence of heart disease on clinical and cardiac magnetic resonance evaluation. A group of healthy athletes with normal ECG served as controls. We evaluated the PMs dimensions, such as diameters, area, volume, mass, and ratio between PMs and left ventricular mass, and the prevalence of PMs apical displacement. Compared with controls, athletes with TWI showed PMs hypertrophy with significantly increased PMs diameters, area, volume, and mass. The ratio between PMs and left ventricular mass was 4.4% in athletes with TWI and 3.0% in controls (P<0.001). A PMs/left ventricular mass ratio >3.5% showed 85% sensitivity and 76% specificity for differentiating between athletes with TWI and controls. Apical displacement of PMs was found in 25 (47%) athletes with TWI versus 9 (17%) controls (P=0.001). At multivariable analysis, PMs/left ventricular mass ratio and apical displacement remained independent predictors of TWI. Clinical outcome of the athletes with TWI and PMs abnormalities was uneventful despite continuation of their sports activity. Conclusions PMs hypertrophy and apical displacement may underlie otherwise unexplained lateral TWI in the athlete. Lateral TWI associated with PMs abnormalities appears as a distinct anatomo-clinical condition characterized by a favorable outcome.

Predictors of Left Ventricular Scar Using Cardiac Magnetic Resonance in Athletes With Apparently Idiopathic Ventricular Arrhythmias.

Background In athletes with ventricular arrhythmias (VA) and otherwise unremarkable clinical findings, cardiac magnetic resonance (CMR) may reveal concealed pathological substrates. The aim of this multicenter study was to evaluate which VA characteristics predicted CMR abnormalities. Methods and Results We enrolled 251 consecutive competitive athletes (74% males, median age 25 [17-39] years) who underwent CMR for evaluation of VA. We included athletes with >100 premature ventricular beats/24 h or ≥1 repetitive VA (couplets, triplets, or nonsustained ventricular tachycardia) on 12-lead 24-hour ambulatory ECG monitoring and negative family history, ECG, and echocardiogram. Features of VA that were evaluated included number, morphology, repetitivity, and response to exercise testing. Left-ventricular late gadolinium-enhancement was documented by CMR in 28 (11%) athletes, mostly (n=25) with a subepicardial/midmyocardial stria pattern. On 24-hour ECG monitoring, premature ventricular beats with multiple morphologies or with right-bundle-branch-block and intermediate/superior axis configuration were documented in 25 (89%) athletes with versus 58 (26%) without late gadolinium-enhancement (P<0.001). More than 3300 premature ventricular beats were recorded in 4 (14%) athletes with versus 117 (53%) without positive CMR (P<0.001). At exercise testing, nonsustained ventricular tachycardia occurred at peak of exercise in 8 (29%) athletes with late gadolinium-enhancement (polymorphic in 6/8, 75%) versus 17 athletes (8%) without late gadolinium-enhancement (P=0.002), (P<0.0001). At multivariable analysis, all 3 parameters independently correlated with CMR abnormalities. Conclusions In athletes with apparently idiopathic VA, simple characteristics such as number and morphology of premature ventricular beats on 12-lead 24-hour ambulatory ECG monitoring and response to exercise testing predicted the presence of concealed myocardial abnormalities on CMR. These findings may help cost-effective CMR prescription.

Italian Cardiological Guidelines (COCIS) for Competitive Sport Eligibility in athletes with heart disease: update 2020.

Since 1989, SIC Sport and a FMSI, in partnership with leading Italian Cardiological Scientific Associations (ANCE, ANMCO and SIC) have produced Cardiological Guidelines for Completive Sports Eligibility for athletes with heart disease (COCIS -- 1989, 1995, 2003, 2009 and 2017). The English version of the Italian Cardiological Guidelines for Competitive Sports Eligibility for athletes with heart disease was published in 2013 in this Journal. This publication is an update with respect to the document previously published in English in 2013. It includes the principal innovations that have emerged over recent years, and is divided into five main chapters: arrhythmias, ion channel disorders, congenital heart diseases, acquired valve diseases, cardiomyopathies, myocarditis and pericarditis and ischemic heart disease. Wherever no new data have been introduced with respect to the 2013 publication, please refer to the previous version. This document is intended to complement recent European and American guidelines but an important difference should be noted. The European and American guidelines indicate good practice for people engaging in physical activity at various levels, not only at the competitive level. In contrast, the COCIS guidelines refer specifically to competitive athletes in various sports including those with high cardiovascular stress. This explains why Italian guidelines are more restrictive than European and USA ones. COCIS guidelines address 'sports doctors' who, in Italy, must certify fitness to participate in competitive sports. In Italy, this certificate is essential for participating in any competition.

Screening young athletes for diseases at risk of sudden cardiac death: role of stress testing for ventricular arrhythmias.

AIMS: The athletic preparticipation evaluation (PPE) protocol proposed by the European Society of Cardiology includes history, physical examination and resting electrocardiogram (ECG). The aim of this study was to assess the results of adding constant-load ECG stress testing (EST) to the protocol for the evaluation of ventricular arrhythmias (VA) inducibility. METHODS: We evaluated a consecutive cohort of young athletes with history, physical examination, resting ECG and EST. Athletes with VA induced by EST underwent 24-hour 12-lead Holter monitoring and echocardiography. Cardiac magnetic resonance (CMR) was reserved for those with frequent, repetitive or exercise-worsened VA, and for athletes with echocardiographic abnormalities. RESULTS: Of 10,985 athletes (median age 15 years, 66% males), 451 (4.1%) had an abnormal history, physical examination or resting ECG and 31 (0.28%) were diagnosed with a cardiac disease and were at risk of sudden cardiac death. Among the remaining 10,534 athletes, VA at EST occurred in 524 (5.0%) and a previously missed at-risk condition was identified in 23 (0.22%); the most common (N = 10) was an echocardiographically silent non-ischaemic left-ventricular fibrosis evidenced by CMR. The addition of EST increased the diagnostic yield of PPE by 75% (from 0.28% to 0.49%) and decreased the positive predictive value by 20% (from 6.9% to 5.5%). During a 32 ± 21 months follow-up, no cardiac arrests occurred among either eligible athletes or non-eligible athletes with cardiovascular disease. CONCLUSIONS: The addition of exercise testing for the evaluation of VA inducibility to history, physical examination and ECG resulted in an increase of the diagnostic yield of PPE at the expense of an increase in false-positive findings.

Levels of circulating pro-angiogenic cells predict cardiovascular outcomes in patients with chronic heart failure.

BACKGROUND: Circulating pro-angiogenic cells (PACs) contribute to vascular and myocardial regeneration. A low level of PACs is associated with worse outcome in patients with coronary heart disease. However, little is known about PACs in heart failure (HF). METHODS AND RESULTS: Blood was sampled at baseline in 111 patients with HF, 67 from 5 Italian Centers and 44 from Frankfurt, Germany. In cultured mononuclear cells from peripheral blood, PACs were counted as double-stained by tetramethylindocarbocyanine-labeled acetylated LDL and fluorescein-5-isothiocyanate-labeled lectin. Mean age of the patients was 62 years, 12 were females, 66 had ischemic etiology, 26 were in New York Heart Association Class >II. Cutoffs for PACs were assessed by receiver operating characteristic curves, to identify the optimal cutoffs for PAC level in predicting outcomes. Mean level of PACs was 35+/-29 (mean+/-SD) cells/mm(2), 2- to 3-fold lower than in age-matched healthy volunteers, but unrelated to severity of HF, age, or sex. Over 2.5 years, 12 cardiovascular deaths and 47 first hospitalizations for cardiovascular reasons were recorded. After adjustment for demographic and clinical variables, elevated creatinine and natriuretic peptides, and PACs

Predictive value of exercise testing in athletes with ventricular ectopy evaluated by cardiac magnetic resonance.

BACKGROUND: Exercise-induced ventricular arrhythmias (EIVA) in young athletes raise the suspicion of an underlying heart disease at risk of sudden death. OBJECTIVE: We aimed to assess the prevalence and determinants of abnormal cardiac magnetic resonance (CMR) findings in athletes referred for EIVA vs non-EIVA with negative or inconclusive echocardiography. METHODS: We performed CMR in a consecutive series of athletes aged 15-50 years referred for frequent (>500 per day) or repetitive premature ventricular beats. Clinical and CMR findings were compared between athletes with EIVA and those with non-EIVA, and predictors of abnormal CMR were assessed. RESULTS: We included 36 athletes with EIVA (median age 25 years; 27 (75%) males) and 24 with non-EIVA (median age 17 years; 18 (75%) males). CMR revealed cardiac abnormalities in 20 athletes with EIVA (56%) and in 5 with non-EIVA (21%) (P = .004). In particular, left ventricular late gadolinium enhancement was identified in 17 athletes with EIVA (47%) and in 3 with non-EIVA (13%) (P = .006), mostly with a nonischemic pattern. Predictors of abnormal CMR were T-wave inversion on electrocardiography (ECG) (odds ratio [OR] 5.2; 95% confidence interval [CI] 1.0-27.1; P = .05), complex ventricular arrhythmias on 24-hour ambulatory ECG monitoring (OR 4.5; 95% CI 1.1-18.7; P = .04), and complex EIVA with a right bundle branch block or polymorphic morphology on exercise testing (OR 5.3; 95% CI 1.4-19.4; P = .01). CONCLUSION: Pathological myocardial substrates on CMR were observed significantly more often in athletes with EIVA than in those with non-EIVA. Repolarization abnormalities on baseline ECG and complex EIVA with a right bundle branch block or polymorphic morphology identified the subgroup of athletes with the highest probability of CMR abnormalities.