CardioSleep Solutions describes 3 ways that OSA may contribute to atrial fibrillation.

Most sleep apnea events end with a surge of the sympathetic branch of the autonomic nerve system. It is also known that the heart electrical system is tightly connected and to some degree regulated by this exact same system.  Therefore, it is assumed that the load sleep apnea is imposing on the system has a profound impact on the promotion of irregular electrical activation patterns or arrhythmias.