Benign and pathological electrocardiographic changes in athletes

Syncope in the athlete - Minor changes, major diagnosis!

We report the case of a 17-year-old athlete who resorted to the emergency department for palpitations and dizziness while exercising. He mentioned two exercise-associated episodes of syncope in the last six months. He was tachycardic and hypotensive. The electrocardiogram showed regular wide complex tachycardia, left bundle branch block morphology with superior axis restored to sinus rhythm after electrical cardioversion. In sinus rhythm, it showed T-wave inversion in V1-V5. Transthoracic echocardiography revealed mild dilation and dysfunction of the right ventricle (RV) with global hypocontractility. Cardiac magnetic resonance (CMR) revealed a RV end diastolic volume indexed to body surface area of 180 ml/m², global hypokinesia and RV dyssynchrony, subepicardial late enhancement in the distal septum and in the middle segment of the inferoseptal wall. The patient underwent a genetic study which showed a mutation in the gene that encodes the desmocolin-2 protein (DSC-2), which is involved in the pathogenesis of arrhythmogenic right ventricular cardiomyopathy (ARVC). According to the modified Task Force Criteria for this diagnosis, the patient presented four major criteria for ARVC. Thus, a subcutaneous cardioverter was implanted, and the patient was followed up at the cardiology department. Arrhythmogenic right ventricular cardiomyopathy diagnosis is based on structural, functional, electrophysiological and genetic criteria reflecting underlying histological changes. This case depicts the essential characteristics for disease recognition.

Variability in interpretation of the electrocardiogram in athletes: Another limitation in pre-competitive screening

INTRODUCTION

Assessment of the electrocardiogram (ECG) in athletes remains controversial, with lack of standardization and difficulty in applying specific criteria in its interpretation. The purpose of this study was to assess variability in the interpretation of the ECG in athletes.

METHODS

Twenty ECGs of competitive athletes were assessed by cardiologists and cardiology residents, 11 of them normal or with isolated physiological changes and nine pathological. Each ECG was classified as normal/physiological or pathological, with or without the use of specific interpretation criteria.

RESULTS

The study presents responses from 58 physicians, 42 (72.4%) of them cardiologists. Sixteen (27.6%) physicians reported that they regularly assessed athletes and 32 (55.2%) did not use specific ECG interpretation criteria, of which the Seattle criteria were the most commonly used (n=13). Each physician interpreted 15±2 ECGs correctly, corresponding to 74% of the total number of ECGs (variation: 45%-100%). Interpretation of pathological ECGs was correct in 68% (variation: 22%-100%) and of normal/physiological in 79% (variation: 55%-100%). There was no significant difference in interpretation between cardiologists and residents (74±10% vs. 75±10%; p=0.724) or between those who regularly assessed athletes and those who did not (77±12% vs. 73±9%; p=0.286), but there was a trend for a higher rate of correct interpretation using specific criteria (77±10% vs. 72±10%; p=0.092). The reproducibility of the study was excellent (intraclass correlation coefficient=0.972; p<0.001).

CONCLUSIONS

A quarter of the ECGs were not correctly assessed and variability in interpretation was high. The use of specific criteria can improve the accuracy of interpretation of athletes' ECGs, which is an important part of pre-competitive screening, but one that is underused.