[Echocardiographic evaluation of the athlete's heart: from morphological adaptations to myocardial function].

The definition of the athlete's heart includes the mechanisms of cardiac adaptation to training, characterized by the increase of internal chamber dimensions, ventricular wall thickness, and atrial chambers. The morphology of the athlete's heart is intermediate between concentric and eccentric left ventricular hypertrophy (LVH), in relation to the large prevalence of mixed sports activities and training protocols (including both aerobic and anaerobic exercise). Echocardiography is the tool of choice for the assessment of the athlete's heart and also for the differentiation of physiologic and pathologic LVH (hypertrophic cardiomyopathy and LVH due to arterial hypertension). The initial echocardiographic approach includes the quantitative analysis of the left ventricle, in order to calculate left ventricular mass, left ventricular mass index and relative wall thickness for diagnosing concentric or eccentric LVH. Tissue Doppler (pulsed or color modality) and strain rate imaging (Doppler or two-dimensional modality) may give additional information to the standard indices of systolic function. Diastolic function can be evaluated not only by standard Doppler transmitral inflow measurements but also using pulsed tissue Doppler, which may allow to distinguish the athlete's LVH from diastolic impairment of hypertensive patients or hypertrophic cardiomyopathy by the simple determination of myocardial early diastolic velocity. Also the morphological and functional features of the left atrium and of the right ventricle can be assessed in the athlete's heart by combining standard echocardiography with new echocardiographic technologies.