A study involving cardiac patients at Sweden’s University Hospital of Umeå shows that over 80% of patients treated for atrial fibrillation (Afib) also have sleep apnea. The study, presented in a dissertation at Umeå University, indicates that the prevalence of sleep apnea is not affected by electrical cardioversion.
“The results of our study emphasizes the importance of examining if patients with cardiac arrhythmia patients also suffer from sleep apnea. Previous studies show that the treatment of atrial fibrillation can be improved if the patient is simultaneously treated for sleep apnea,” says Niklas Höglund, doctoral student at the Department of Public Health and Clinical Medicine, in a release.
Afib is a condition of abnormal heart rhythm and can be treated using electrical cardioversion, a treatment converting the heart rhythm through electrical shock. In the current study, carried out at the University Hospital of Umeå, 23 patients who needed electric cardioversion treatment for atrial fibrillation were offered sleep apnea evaluation before and after the treatment. None of the patients in the study had a previously known sleep apnea.
The results showed that 74% of the participants had obstructive sleep apnea while 26% had central sleep apnea. Five individuals in the study had both obstructive and central sleep apnea. The follow-up showed that electrical cardioversion treatment for atrial fibrillation did not affect the prevalence of sleep apnea.
“Obstructive sleep apnea contributes to the increase of atrial fibrillation by generating a negative pressure in the chest while breathing through closed airways, which affects the heart’s atria. Furthermore, lack of oxygen, increased carbon dioxide levels in the blood and secretion of stress hormones can also lead to the development of atrial fibrillation,” says Höglund.
Höglund is a specialist in general medicine and cardiology and is now senior physician at the Arrhythmia Clinic at the Heart Centre at the University Hospital of Umeå. His main field of work is invasive arrhythmia treatment.