SESSION TYPE: Cardiovascular Case Report Posters
PRESENTED ON: Monday, October 22, 2012 at 01:30 PM - 02:30 PM
INTRODUCTION: There is a well-known pathophysiologic and epidemiologic relationship between obstructive sleep apnea (OSA) and atrial fibrillation (AF).  We present the first description of brief paroxysms of AF temporally associated with discrete obstructive events in an individual with no known cardiovascular disease.
CASE PRESENTATION: A 43 year-old man with no significant past medical history was referred for evaluation of snoring, excessive daytime sleepiness, and witnessed apneas. Physical examination was significant for a body mass index of 40 kg/m2 and a Mallampati score of 4. His baseline electrocardiogram demonstrated normal sinus rhythm (NSR). A level 1, in-laboratory nocturnal polysomnogram (PSG) was performed according to standard techniques, which revealed severe OSA with an apnea-hypopnea index of 83 events/hour and nadir oxygen saturation of hemoglobin of 62%. He underwent a split-night study and was titrated to 11 cm H2O. Paroxysms of AF associated with obstructive events were observed; the mean duration of AF was 24 seconds (+/- 22 seconds). There were a total of 20 paroxysms during the diagnostic portion and one event during the titration portion of the study while at sub-optimal pressure.
DISCUSSION: Although prior reports have noted OSA triggering episodes of AF , our report describes a patient with no previous history of structural heart disease or AF with evidence of discrete paroxysms of AF seen during severe apneic episodes and oxygen desaturation. The mechanism behind this association is not clear, although autonomic dysfunction related to apneic events and intrathoracic pressure swings resulting in conduction abnormalities  may be contributory and/or causative. This finding adds to accumulating evidence linking discrete obstructive respiratory events with arrhythmogenesis in OSA and its diminution with adequate treatment.
CONCLUSIONS: While it is well accepted that AF and OSA are epidemiologically associated, we believe we have demonstrated a direct causal relationship between discrete obstructive respiratory events and the initiation of AF.
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DISCLOSURE: The following authors have nothing to disclose: Vishal Patel, Ruchi Bansal, Jeremy Weingarten
No Product/Research Disclosure InformationNew York Methodist Hospital, Brooklyn, NY