Recommendations and cardiological evaluation of athletes with arrhythmias: Part 2.

Confronted with a competitive or recreational athlete, the physician has to discriminate between benign, paraphysiological and pathological arrhythmias. Benign arrhythmias do not represent a risk for SCD, nor do they induce haemodynamic consequences during athletic activities. These arrhythmias are not markers for heart disease. Paraphysiological arrhythmias are related to athletic performance. Long periods of endurance training induce changes in rhythm, conduction and repolarisation. These changes are fully reversible and disappear when the sport is terminated. Pathological arrhythmias have haemodynamic consequences and express disease, such as sick sinus syndrome, cardiomyopathy or inverse consequences of physical training. Arrhythmias can be classified as bradyarrhythmias and tachyarrhythmias. Conduction disorders can be seen in fast as well as in slow arrhythmias.