Mobitz II atrioventricular block and CPAP response in a patient with severe obstructive sleep apnea, a case report

Abstract Background At any stage during the sleep cycle, cardiac arrhythmia can happen. While many of these arrhythmias are benign, some of them are dangerous and may result in cardiovascular events that could be life-threatening. Bradycardic arrhythmias can result from obstructive sleep apnea (OSA) and are associated with mechanisms involving autonomic activity, decreased oxygen saturation, cyclic changes in sympathovagal balance, and hemodynamic alterations in the heart. Some blocks improve with continuous positive airway pressure (CPAP) therapy, while others show little change. Since rapid eye movement (REM) sleep-related arrhythmias have been observed to continue even after CPAP treatment, they are now categorized as a distinct category and seem to be influenced by factors other than increased parasympathetic activity. Case presentation In this study, we report a patient who had severe obstructive sleep apnea with second-degree atrioventricular block (AV block) during sleep. The patient's REM sleep arrhythmia persisted even after using CPAP. Conclusions The varying outcomes of the therapeutic response of heart block in hypopnea to CPAP are most likely caused by the patient's varying sleep stages at the time of the blocks.