title: [ECG of the athlete's heart].
abstract: The athlete's heart is characterized by eccentric hypertrophy of all cardiac cavities and there is a close connection to increased tone of the vagal system. As a consequence, not only arrhythmias are observed in the ECG of healthy athletes, but also changes in the QRS complex and in the ST-T-segment. Left ventricular hypertrophy is diagnosed in ECG by a positive Sokolow-Lyon index. The frequent finding of a right ventricular conduction delay is possibly due to hypertrophy of the myocardium in the apex of the right ventricle. The causes of various T wave changes are generally unclear and await further diagnostic clarification. In cases when normalization of the T-wave deviation is observed under stress, such changes are of functional nature. Echocardiography is indicated in any case to establish the heart's size and function; hypertrophic cardiomyopathy has to be excluded. Frequent cardiac dysrhythmias found in athletes are sinus bradycardia and sinus arrhythmia, less often escape rhythms are seen. A arrhythmia more often found in athletes is the respiration-dependent simple atrioventricular dissociation. Also, escape rhythms are observed in some cases with ventricular origin. Finally, a pronounced vagotonia can lead to a prolonged conduction time; AV-blocks of all degrees of severity are observed in athletes. The functional character of these arrhythmias can be easily demonstrated by their disappearance under stress.
authors.affiliation: Abteilung Kardiologie, Medizinische Universitätsklinik Graz.
authors.forename: R
authors.initials: R
authors.lastname: Pokan
authors.forename: M
authors.initials: M
authors.lastname: Huonker
authors.forename: M
authors.initials: M
authors.lastname: Schumacher
authors.forename: R
authors.initials: R
authors.lastname: Zweiker
authors.forename: B
authors.initials: B
authors.lastname: Eber
authors.forename: I
authors.initials: I
authors.lastname: Starz
authors.forename: W
authors.initials: W
authors.lastname: Klein
mesh_terms: D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000503:physiopathology*; D002306:Cardiac Volume / Q000502:physiology; D006332:Cardiomegaly / Q000175:diagnosis / Q000503:physiopathology*; D003937:Diagnosis, Differential; D004452:Echocardiography; D004562:Electrocardiography; D006329:Heart Conduction System / Q000503:physiopathology; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D010807:Physical Endurance / Q000502:physiology; D010809:Physical Fitness / Q000502:physiology; D013177:Sports / Q000502:physiology*