Atrial fibrillation during road cycling - What can be done to prevent atrial fibrillation during road cycling?

Question from TOUR reader Mike S.: A few days ago I (48 years old, 188 cm, 86 kilos) had to go to hospital. Diagnosis: atrial fibrillation. As the problem did not resolve itself after 24 hours, which is probably not unusual, electrocardioversion was used to bring my heart back into sinus rhythm. No abnormalities were found on ultrasound and X-ray images of my heart. Now I have to take beta blockers in the morning and evening. Is my cycling career history or is there hope for more kilometres in the saddle?

Answer from Dr Robert Eifler: Atrial fibrillation is a rapid, irregular activity of the region of the heart called the "atrium" with uncoordinated conduction of blood to the ventricles. It occurs more frequently in adults with increasing age and can be completely asymptomatic; however, symptoms such as palpitations, reduced exercise tolerance, dizziness, reduced blood pressure, shortness of breath - and in extreme cases, fainting - are more common.
and, in extreme cases, fainting. The cause is impaired conduction from the atrium to the ventricles, the diagnosis is confirmed by an electrocardiogram (ECG). In the further course, structural heart diseases such as valve defects, high blood pressure, hyperthyroidism or alcohol abuse must be ruled out.

Atrial fibrillation can occur under stress even after a night of drinking! Trained cyclists often have a basically harmless enlargement of the right atrium due to the enlargement of the heart, which can nevertheless trigger atrial fibrillation by stretching the conduction system. Acutely, this manifests itself as if you were driving with the brakes on. If the atrium does not contract, the ventricles fill with significantly less blood and performance decreases. There is also a risk of clots forming, particularly in the left atrium, with the risk of an embolism, which can lead to a stroke.

Atrial fibrillation can disappear spontaneously. If this is not the case, medication is tried first; if this does not work, electrocardioversion is used. If atrial fibrillation recurs, catheter ablation is another treatment option. In all cases, drug therapy with an anticoagulant and a rhythm-stabilising drug should be continued. Beta-blockers are tried and tested, but do not allow absolute peak performance. You can continue to ride a racing bike under the indicated therapy, but active racing activity is not recommended.