1253 Sleep Onset Initiated, REM Onset Relieved “Vagally Mediated Atrial Flutter”

Abstract

Introduction: Sleep is considered a restorative period, however dynamic cardiovascular control during sleep may constitute it as an autonomic stress test for the heart.1,2 Most studies of circadian patterns of atrial tachyarrhythmias (AF/AT) have been limited to ambulatory ECG data.3 This case demonstrates that polysomnography (PSG) can have a role in identification and proper management of arrhythmias during sleep. In our case, paroxysmal atrial flutter presented precisely at the point of sleep onset, and was relieved with the first REM onset. Report of Case: 44-year-old female with past medical history of refractory paroxysmal atrial flutter since 2009, obesity with BMI 49.16 kg/m2, Grave's disease s/p radioiodine ablation, referred for evaluation of OSA. Medications included flecainide, digoxin, rivaroxaban, risperidone, quetiapine, levothyroxine, aspirin, atorvastatin. During the PSG, patient was noted to have normal sinus rhythm during awake period which was disrupted into paroxysmal AF precisely at onset of sleep and converted back to normal sinus rhythm at first REM onset. [Figures 1-5] Conclusion: The phenomenon of vagal mediated paroxysmal atrial fibrillation was first described in 1994 by P. Coumel, however specific contributions of vagal and sympathetic ANS effects on arrhythmogenesis are still being debated.2 At present, there is no clear evidence for differentiating medical treatment for nighttime versus daytime atrial fibrillation. Identifying circadian patterns of arrhythmia and underlying pathophysiology on an individual basis remains a major challenge yet has therapeutic implications. Commonly used AF therapies including beta blockers and digoxin have been shown to be not beneficial and even arrhythmogenic in vagal AF.3,4 Our case demonstrates the importance of PSG evaluation in understanding pathogenesis and diagnosis of sleep related vagally mediated arrhythmias. The case attempts to bring the attention of cardiologists and electro-physiologists in utilization of PSG studies in evaluating patients with nocturnal related arrhythmias.