Noninvasive Cardiac Screening in Young Athletes With Ventricular Arrhythmias

The aim of this study was to analyze using noninvasive cardiac examinations a series of young athletes discovered to have ventricular arrhythmias (VAs) during the preparticipation screening program for competitive sports. One hundred forty-five athletes (mean age 17 ± 5 years) were evaluated. The study protocol included electrocardiography (ECG), exercise testing, 2-dimensional and Doppler echocardiography, 24-hour Holter monitoring, signal-averaged ECG, and in selected cases contrast-enhanced cardiac magnetic resonance imaging. Results of ECG were normal in most athletes (85%). VAs were initially detected prevalently during exercise testing (85%) and in the remaining cases on ECG and Holter monitoring. Premature ventricular complexes disappeared during exercise in 56% of subjects. Premature ventricular complexes during Holter monitoring averaged 4,700 per day, predominantly monomorphic (88%), single, and/or in couplets (79%). The most important echocardiographic findings were mitral valve prolapse in 29 patients (20%), congenital heart disease in 4 (3%), and right ventricular regional kinetic abnormalities in 5 (3.5%). On cardiac magnetic resonance imaging, right ventricular regional kinetic abnormalities were detected in 9 of 30 athletes and were diagnostic of arrhythmogenic right ventricular cardiomyopathy in only 1 athlete. Overall, 30% of athletes were judged to have potentially dangerous VAs. In asymptomatic athletes with prevalently normal ECG, most VAs can be identified by adding an exercise test during preparticipation screening. In conclusion, cardiac screening with noninvasive examinations remains a fundamental tool for the identification of a possible pathologic substrate and for the characterization of electrical instability. The aim of this study was to analyze using noninvasive cardiac examinations a series of young athletes discovered to have ventricular arrhythmias (VAs) during the preparticipation screening program for competitive sports. One hundred forty-five athletes (mean age 17 ± 5 years) were evaluated. The study protocol included electrocardiography (ECG), exercise testing, 2-dimensional and Doppler echocardiography, 24-hour Holter monitoring, signal-averaged ECG, and in selected cases contrast-enhanced cardiac magnetic resonance imaging. Results of ECG were normal in most athletes (85%). VAs were initially detected prevalently during exercise testing (85%) and in the remaining cases on ECG and Holter monitoring. Premature ventricular complexes disappeared during exercise in 56% of subjects. Premature ventricular complexes during Holter monitoring averaged 4,700 per day, predominantly monomorphic (88%), single, and/or in couplets (79%). The most important echocardiographic findings were mitral valve prolapse in 29 patients (20%), congenital heart disease in 4 (3%), and right ventricular regional kinetic abnormalities in 5 (3.5%). On cardiac magnetic resonance imaging, right ventricular regional kinetic abnormalities were detected in 9 of 30 athletes and were diagnostic of arrhythmogenic right ventricular cardiomyopathy in only 1 athlete. Overall, 30% of athletes were judged to have potentially dangerous VAs. In asymptomatic athletes with prevalently normal ECG, most VAs can be identified by adding an exercise test during preparticipation screening. In conclusion, cardiac screening with noninvasive examinations remains a fundamental tool for the identification of a possible pathologic substrate and for the characterization of electrical instability. Athlete's heart is generally regarded as a benign electroanatomic remodeling due to systematic training. Nevertheless, repolarization inhomogeneity of myocardium, a high prevalence of ventricular arrhythmias (VAs), and arrhythmogenic right ventricular (RV) cardiomyopathy–like phenotypes have been described in some athletes.1Maron B.J. Pelliccia A. The heart of trained athletes: cardiac remodeling and the risk of sports, including sudden death.Circulation. 2006; 114: 1633-1644Crossref PubMed Scopus (534) Google Scholar, 2Varró A. Baczkó I. Possible mechanisms of sudden death in top athletes: a basic cardiac electrophysiological point of view.Pflugers Arch. 2010; 460: 31-40Crossref PubMed Scopus (38) Google Scholar, 3Palatini P. Maraglino G. Sperti G. Calzavara A. Libardoni M. Pessina A.C. Dal Palù C. Prevalence and possible mechanisms of ventricular arrhythmias in athletes.Am Heart J. 1985; 110: 560-567Abstract Full Text PDF PubMed Scopus (66) Google Scholar, 4Heidbüchel H. Hoogsteen J. Fagard R. Vanhees L. Ector H. Willems R. Van Lierde J. High prevalence of right ventricular involvement in endurance athletes with ventricular arrhythmias. Role of an electrophysiologic study in risk stratification.Eur Heart J. 2003; 24: 1473-1480Crossref PubMed Scopus (314) Google Scholar, 5La Gerche A. Robberecht C. Kuiperi C. Nuyens D. Willems R. de Ravel T. Matthijs G. Heidbüchel H. Lower than expected desmosomal gene mutation prevalence in endurance athletes with complex ventricular arrhythmias of right ventricular origin.Heart. 2010; 96: 1268-1274Crossref PubMed Scopus (147) Google Scholar Sports are associated with an increased risk for sudden death in athletes who are affected by cardiovascular conditions predisposing to life-threatening VAs during exercise.6Corrado D. Basso C. Rizzoli G. Schiavon M. Thiene G. Does sports activity enhance the risk of sudden death in adolescents and young adults?.J Am Coll Cardiol. 2003; 42: 1959-1963Abstract Full Text Full Text PDF PubMed Scopus (1001) Google Scholar The incidence of sudden cardiac death in young competitive athletes has substantially decreased in the Veneto region of Italy thanks to the introduction of a preparticipation screening program that identifies subjects with previously unrecognized cardiovascular conditions.7Corrado D. Basso C. Pavei A. Michieli P. Schiavon M. Thiene G. Trends in sudden cardiovascular death in young competitive athletes after implementation of a preparticipation screening program.JAMA. 2006; 296: 1593-1601Crossref PubMed Scopus (1161) Google Scholar Rhythm and conduction abnormalities are the first cardiovascular causes of sports disqualification, and evaluation of VAs constitutes an important medical and legal issue.7Corrado D. Basso C. Pavei A. Michieli P. Schiavon M. Thiene G. Trends in sudden cardiovascular death in young competitive athletes after implementation of a preparticipation screening program.JAMA. 2006; 296: 1593-1601Crossref PubMed Scopus (1161) Google Scholar The aim of this study was to analyze using noninvasive cardiac examinations a series of young athletes discovered to have VAs. One hundred forty-five young, nonelite, competitive athletes (mean age 17.3 ± 5.3 years, range 9 to 34; male/female ratio 106/39 = 2.7) were evaluated in our laboratory during a period of 3 years. All subjects were referred because of VAs detected during preparticipation screening, which also included exercise testing. The study protocol included family and personal histories, 12-lead electrocardiography (ECG), 2-dimensional echocardiography with Doppler analysis, 24-hour Holter monitoring, exercise testing, signal-averaged ECG, and in selected cases contrast-enhanced cardiac magnetic resonance imaging. Electrocardiograms were evaluated using digital calipers at standard paper speed (25 mm/s). Electrocardiographic abnormalities were divided into 2 groups (common or training-related and uncommon or training-unrelated abnormalities) and interpreted considering the most recent recommendations.8Corrado D. Pelliccia A. Heidbuchel H. Sharma S. Link M. Basso C. Biffi A. Buja G. Delise P. Gussac I. Anastasakis A. Borjesson M. Bjørnstad H.H. Carrè F. Deligiannis A. Dugmore D. Fagard R. Hoogsteen J. Mellwig K.P. Panhuyzen-Goedkoop N. Solberg E. Vanhees L. Drezner J. Estes III, N.A. Iliceto S. Maron B.J. Peidro R. Schwartz P.J. Stein R. Thiene G. Zeppilli P. McKenna W.J. Section of Sports Cardiology, European Association of Cardiovascular Prevention and Rehabilitation Working Group of Myocardial and Pericardial Disease, European Society of CardiologyRecommendations for interpretation of 12-lead electrocardiogram in the athlete.Eur Heart J. 2010; 31: 243-259Crossref PubMed Scopus (674) Google Scholar, 9Uberoi A. Stein R. Perez M.V. Freeman J. Wheeler M. Dewey F. Peidro R. Hadley D. Drezner J. Sharma S. Pelliccia A. Corrado D. Niebauer J. Estes III, N.A. Ashley E. Froelicher V. Interpretation of the electrocardiogram of young athletes.Circulation. 2011; 124: 746-757Crossref PubMed Scopus (177) Google Scholar Signal-averaged ECG was performed using a MAC15 system (Marquette Inc., Milwaukee, Wisconsin). The following parameters for each of the 3 filters (25, 40, and 80 to 250 Hz) were evaluated: filtered QRS duration, high-frequency low-amplitude signal duration in the terminal portion of the filtered QRS interval with a voltage amplitude <40 μV (or <20 μV for the 80- to 250-Hz filter), and the root mean square of the voltage in the last 40 ms of the filtered QRS interval. Presence of late potentials was considered when ≥2 parameters were abnormal in 1 filter. The exercise test was performed on a bicycle or treadmill (with standard 12-lead placement) up to the submaximal heart rate, calculated from the formula 220 − age × 85%. ST-segment alterations and VAs were carefully evaluated. Holter monitoring was performed using 12-lead ECG (with standard lead placement). The number, morphologies, and coupling intervals of single and repetitive VAs were studied. The echocardiographic study was performed with a 2.5- to 4-MHz transducer (model 5500, Philips Medical Systems, Andover, Massachusetts) and included M-mode, 2-dimensional, and Doppler examinations of the traditional views. Left ventricular (LV) end-diastolic diameter, parietal wall thickness, and left atrial diameter were calculated in the parasternal long-axis view using M-mode imaging. LV end-diastolic volume, end-systolic volume, and ejection fraction were calculated in the apical 4-chamber view (using Simpson's rule). RV end-diastolic area, end-systolic area, and fractional area change were calculated from the apical 4-chamber view, and the RV ejection fraction was also measured. The RV outflow tract was measured in the parasternal view and the short-axis view and the RV inflow tract in the 4-chamber view. The presence of LV and RV wall motion abnormalities was assessed. Cardiac magnetic resonance imaging was performed using a 1.0-T clinical scanner (Harmony; Siemens Healthcare, Erlangen, Germany) using a phased-array cardiac receiver coil. After the intravenous administration of gadolinium, chelate inversion recovery prepared, breath-hold cine gradient-echo images were obtained. Cine, morphologic, and late gadolinium enhancement images acquired during the same imaging session were matched by slice position. Data are expressed as mean ± SD for continuous variables and as frequencies with percentages for categorical variables. All continuous variables are expresses as mean ± SD. The initial detection of premature ventricular complexes (PVCs) during the preparticipation program was due mostly to the exercise tests in 124 athletes (85%). In the remaining cases, were on ECG athletes or detected on Holter monitoring athletes were normal in athletes (85%) with the abnormalities) and abnormal in with the uncommon of ± electrical QRS ± interval ± QRS duration ± interval ± and QRS voltage for LV = ± were All athletes were in right of the QRS complex in athletes was considered The abnormalities were in athletes in 4 right in in QRS voltage in 17 and repolarization in The uncommon abnormalities were left or right atrial in 4 athletes ventricular in 1 in 3 of RV in 2 ST-segment abnormalities in 4 ST-segment in 2 in and interval in 3 to were in athletes in lead were in athletes were in to age to to and ≥2 conduction with QRS ms were in 4 athletes in with in or were on ECG in athletes Signal-averaged ECG was performed in athletes late in 1 and 4 in 2 The mean of each were filtered QRS duration ± ± and ± high-frequency low-amplitude signal duration ± ± and ± and root mean square of the voltage in the last 40 ms of the filtered QRS interval ± ± and ± echocardiographic findings of heart were detected in subjects In LV end-diastolic diameter was increased in (mean ± 5 and ejection were normal (mean ± in a parietal wall wall ± wall ± were normal in = ± = ± 1 in were normal = ± = ± = ± Left or right atrial was in athletes The presence of LV was detected in RV end-diastolic area was in (mean ± 4 The RV inflow tract was increased in in The RV outflow tract in the parasternal view was increased in in 3 and the RV outflow tract in the short-axis view was increased in in 2 RV was normal area change ± ejection fraction ± in 1 and were RV in were normal in = ± = ± = ± were detected in the valve the mitral valve the valve and the valve One valve prolapse was in 29 athletes 4 with heart disease was detected in 4 athletes a a ventricular a and a left The of arrhythmogenic RV cardiomyopathy was in 3 subjects and RV apical was in 2 echocardiographic findings detected in the findings = valve heart valve with ventricular and left a was also arrhythmogenic RV findings = than 1 was in some subjects. RV Pericardial LV RV LV mitral left valve with ventricular and left a was also than 1 was in some subjects. in a Holter monitoring a mean of of 4,700 per The of from to per in athletes from to per in from to per in 29 (20%), and from to per in 17 and was per in 4 In subjects <20 per and were judged single were detected in athletes and in the remaining repetitive were also detected in of subjects coupling intervals mean ± the athletes with of in (88%), were The most were left with in subjects with left in with in with right in with normal in and with in was considered and and of athletes ventricular couplets in in with a mean coupling interval of ± ms in in 5 ventricular couplets were per and in 1 were and ventricular was in athletes to 17 (mean and from 4 to (mean In 4 of were athletes = single of during the The mean ventricular of was (mean interval 4 with 9 with of to with of to and with 4 athletes of Overall, were judged potentially dangerous on the of or exercise or the presence of an Estes III, N.A. 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