Electrocardiographic Changes in Athletes of Black Ethnicity

Abstract

AbstractIntensive participation in sport has positive physiological effects on the heart. The contractility of the heart improves, the ejection fraction increases and the muscle mass of the heart increases, thus leading to a greater cardiac output. Despite these positive effects, there is still an increased risk for acute cardiac events. The workload of the heart can be very high in some sports and may in some cases be the reason for sudden cardiac death. In these cases, there is often an underlying heart disease (cardiomyopathy) unknown before the actual event. Electrocardiographic examination (ECG) may reveal some of these diseases but although ECG examinations can be a useful tool to discover pathological conditions, there could be difficulties in interpreting different ECG patterns, especially in athletes. In some cases, athletes may exhibit ECG patterns that are similar to those in heart diseases such as cardiomyopathies (QRS-amplitudes, ST-segment elevation and T wave inversions in lateral leads).  This pattern is even more common in athletes of African origins. Furthermore, cardiomyopathies such as hypertrophic cardiomyopathy (HCM) are more common among athletes with African heritage than in white athletes. Thus correct interpretation of ECG is crucial for several reasons: to distinguish between benign physiological (‘athlete’s heart’) and pathological changes, to lower the risk of sudden cardiac death, and to save time and money by not undertaking further examination of the heart.