Noch eine Fundsache (ein paar Auszüge):

Link MS, Wang PJ, Estes NA 3rd.: Ventricular arrhythmias in the athlete, in: Curr Opin Cardiol. 2001 Jan;16(1):30-9.
In athletes under the age of 30 years the incidence of sudden death is low. In most cases sudden death only occurs in individuals with inherited heart disease.
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Sudden death nearly always occurs in the presence of structural heart disease. In 158 young competitive athletes with sudden death, Maron et al.[14•] found a cardiovascular cause in 85%. Of the 134 athletes with a cardiovascular cause of death, structural heart disease was found in 97%.
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Symptoms of arrhythmias in the athlete are similar to the nonathlete and range from brief palpitations to syncope and resuscitated sudden death. The evaluation of athletes is similar to other patients with possible symptoms and signs of arrhythmic disorders. The key elements of the evaluation include the severity of the symptoms, the presence or absence of structural heart disease, and the family medical history. As a general rule the severity of the symptoms is related to the risk of ventricular arrhythmias and sudden death. Thus, palpitations are frequently benign; presyncope and certainly syncope are more concerning, and resuscitated sudden death is of utmost worry. Palpitations are a frequent complaint and can be secondary to atrial premature beats, ventricular premature beats, supraventricular or ventricular tachycardias, or even anxiety and normal sinus rhythm.
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In the setting of a normal heart, nonsustained ventricular tachycardia and frequent premature ventricular contractions, even if exercise induced, do not increase the risk of subsequent sudden death [50–52] (Table 3). Athletes who present with one of these arrhythmias should have a workup for structural heart disease that includes an echocardiogram and exercise testing. If the athlete's heart is completely normal, treatment is not needed, nor is restriction from sports.

Curr Sports Med Rep. 2002 Apr;1(2):75-85.

Cardiac arrhythmias in the athlete: the evolving role of electrophysiology.

Link MS, Homoud MK, Wang PJ, Estes NA 3rd.

New England Medical Center, Box #197, 750 Washington Street, Boston, MA 02111, USA. MLink@Lifespan.org

Arrhythmia management has undergone a revolution in the past decade. The diagnosis and treatment of arrhythmias in the athlete can be complicated by the need to compete and exercise. Some arrhythmias may be benign and asymptomatic, but others may be life threatening. Sinus bradyarrhythmias are common and even expected in athletes; these are rarely a cause for concern. Heart block is unusual and merits a thorough work-up. Atrial fibrillation may be more common in the athlete, and supraventricular tachycardias other than atrial fibrillation warrant consideration of radiofrequency ablation for cure. Ventricular arrhythmias in the athlete generally occur in the setting of structural heart disease that is genetically determined (hypertrophic cardiomyopathy, arrhythmogenic right ventricular dysplasia, anomalous coronary arteries), or acquired (coronary artery disease, myocarditis, idiopathic dilated cardiomyopathies). In these conditions the arrhythmia is life threatening. Ventricular arrhythmias that occur in the athlete without structural heart disease are not thought to be life threatening. Athletes with structural heart disease and those with exertional syncope merit a complete evaluation.