Incident Arrhythmias Detected Using Implantable Loop Recorders in Obstructive Sleep Apnoea.

Background: Obstructive sleep apnoea (OSA) is highly prevalent in Western populations, causing breathing cessation during sleep due to airway collapse. OSA is strongly associated with cardiovascular disease and arrhythmia, with several mechanisms likely to increase arrhythmia incidence. Continuous positive airway pressure (CPAP) is the mainstay of treatment, and whilst CPAP effectively treats OSA, specific arrhythmias and major adverse cardiovascular events may remain unchanged. Furthermore, arrhythmias are likely significantly underdiagnosed in this population. Meanwhile, implantable loop recorders (ILRs) are the gold-standard detection method for arrhythmias. Methods: This review aimed to systematically evaluate observational studies using ILRs to identify the incidence of arrhythmia in treated OSA patients. We searched the Medline/Excerpta Medica Database (EMBASE) databases, identifying observational studies involving any OSA patients with no history of arrhythmia and who had ILRs inserted. Two reviewers assessed the quality of the studies and potential bias using the Observational Study Quality Evaluation (OSQE) tool. Results: Three studies met the criteria with 77 participants; however, the study outcomes were incomparable and could not be pooled. CPAP significantly reduced bradyarrhythmia/pauses. There was a high incidence of atrial fibrillation (AF), up to 31%, although the sample size and overall characteristics were insufficient and could not be generalized. AF and other tachyarrhythmias were likely underdiagnosed in OSA patients. CPAP did reduce bradyarrhythmia/pauses but is potentially insufficient to reduce AF or other tachyarrhythmias. Only one ongoing study was found to evaluate the incidence of arrhythmias in OSA. Conclusions: We highlight the need for arrhythmia screening in OSA patients and for further studies to clarify the true incidence of arrhythmias in OSA patients. These additional studies may influence the guidelines for arrhythmia screening and identify mechanisms and therapeutic targets in OSA.