Noninvasive cardiac screening in young athletes with ventricular arrhythmias

Abstract

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.

Figure 1

The most frequent morphologies of PVCs in our cohort of athletes. The first 5 cases of PVCs were characterized by LBBB morphology with variable axis deviation, and the next 4 cases of PVCs were characterized by RBBB morphology with variable axis deviation.

Figure 2

Flow diagram demonstrating the workout and results of cardiologic screening. In 43 athletes (30%), VAs were judged to be potentially dangerous on the basis of the arrhythmic pattern (complex idiopathic VAs or VAs triggered by mild abnormalities) and/or the presence of organic heart disease or nonspecific abnormalities on cardiac magnetic resonance imaging (CMR) that diagnosis was not definite. The box labeled “definitive diagnosis of organic heart disease” included 4 congenital diseases/abnormalities, 1 arrhythmogenic RV cardiomyopathy, and 1 pericardial effusion. The box labeled “mild abnormalities” mostly included mitral valve prolapse and also mild mitral regurgitation, atrial septal aneurysm, RV apical hypokinesia, 1 case of mild aortic regurgitation, and 1 case of moderate LV enlargement. The box labeled “idiopathic ventricular arrhythmias” included VAs in the absence of structural disease or VAs not related to the type of abnormality. VPC = premature ventricular complex.