The hearts of competitive athletes: An up-to-date overview of exercise-induced cardiac adaptations

Abstract

Intense and regular physical exercise is responsible for various cardiac changes (electrical, structural and functional) that represent physiological adaptation to exercise training. This remodeling, commonly referred to as 'athlete's heart', can overlap with several pathological entities, in which sudden cardiac death may be the first clinical presentation. Although pre-competitive screening can identify athletes with life-threatening cardiovascular abnormalities, there are no widely used standardized pre-participation programs and those currently implemented are controversial. Data from personal and family history, features of physical examination and changes in the 12-lead electrocardiogram can raise the suspicion of cardiac disease and lead to early detection of entities such as hypertrophic cardiomyopathy. However, interpreting the electrocardiogram is often challenging, because some changes are considered physiological in athletes. Thus, clinical decision-making in such cases can prove difficult: missing a condition associated with an increased risk of life-threatening events, or conversely, mislabeling an athlete with a disease that leads to unnecessary disqualification, are both situations to avoid. This paper provides an up-to-date review of the physiological cardiac effects of exercise training and highlights key points that should be taken into consideration in the assessment of young competitive athletes.

Echocardiography in non‐ischemic cardiomyopathies: differential diagnosis from athlete's heart

“…Several issues influence the presence and the magnitude of cardiac remodeling, being the most relevant demographic factors (e.g., age, gender, body surface area, and ethnicity) and exercise-related characteristics (e.g., sport-type intensity of training and level of competition) ( Figure 1) [1]. The knowledge of these characteristics during the athletes' assessment and the integration of these data with additional investigations, such as TTE, is essential.…”

“…The integration of the data of other exams as cardiopulmonary exercise testing and cardiac magnetic resonance (CMR) permits an accurate assessment of athletes in the "gray zone" [1].…”

“…Regular physical exercise and training induce complex physiological cardiac remodeling-electrical, functional, and structural, in order to accommodate a state of enhanced cardiovascular performance [1]. These adaptations, traditionally called as "athlete's heart," are characterized by a homogeneous chamber enlargement and increased mass and wall thickness (WT), more pronounced in left ventricle (LV).…”

“…These adaptations, traditionally called as "athlete's heart," are characterized by a homogeneous chamber enlargement and increased mass and wall thickness (WT), more pronounced in left ventricle (LV). The magnitude and extension of these adaptations are related to individual demographic and exercise-related characteristics [1]. Although the classical Morganroth hypothesis postulates that strength exercise induces concentric hypertrophy due to pressure overload and endurance exercise induces eccentric hypertrophy due to volume overload, it is currently known that most sports share both types of exercise, leading to isoforms with mixed remodeling [2][3][4].…”

“…Some of the structural cardiac changes seen in athletes can overlap common findings of several pathologic conditions, mainly non-ischemic cardiomyopathies, frequently associated with an increased risk of sudden cardiac death (SCD) [5].The hallmark of this evaluation is the differential diagnosis between "athlete 0 s heart" and hypertrophic cardiomyopathy (HCM), an important cause of SCD in young athletes in countries in which systematic ECG is not performed in pre-participation screening programs. However, the overlap with dilated cardiomyopathy (DCM), LV non-compactation (LVNC), or arrythmogenic right ventricle cardiomyopathy (ARVC) is also common, mainly in sports characterized by a high-intensity level of dynamic exercise [1,5]. The management and evaluation of these athletes with "gray zone" findings is based on clinical evaluation, ECG, and imaging methods, where echocardiography play pivotal role.…”