effect of oral appliance therapy on atrial fibrillation

Conditions: Atrial Fibrillation

Summary: this pilot study is expected to determine the efficacy of using the midline traction designed mytap plus mouth shield (mytap + ms) oral appliance combination in decreasing the number of atrial fibrillation events. the ms is a patient comfort accessory to the mytap.

atrial fibrillation (af) is highly prevalent in the u.s. and possesses a greater risk in patients with sleep disordered breathing (sdb) versus patients without sdb. af recurrence after catheter ablation is associated with 25% increased risk in patients with obstructive sleep apnea (osa). one hypothesis suggests that the repeated hypoxic episodes time-linked to osa and central sleep apnea may act as chemo-reflex triggers that enhances brainstem sympathetic activity in conjunction with responses to osa-event hypoxia. this hypothesis is believed to induce tachycardia and cardiovascular stress. in an animal model, episodes of hypoxia were shown to induce pulmonary vein burst firing and reduction of the negative tracheal pressure promptly restored normal sinus rhythm. the trigemino-cardiac reflex hypothesis implicates chemo- and mechanoreceptors in the oronasal cavity that provides signaling to the reticular formation via the mesencephalic nucleus of the trigeminal nerve and serves to control breathing, cardiac function, blood ph (acidity), amongst other body functions. the sympathetic system in patients with osa syndrome is considered to be chronically hypersensitized. a hyperarousal state suggests af patients with osa would tend to have af occur more frequently in conjunction with apnea hypopnea events. an increase in autonomic sympathetic cardiac dominance with a withdrawal of cardiac parasympathetic control could easily be driven by mechanoreceptors in the oropharynx upon airway narrowing and present as decreased heart rate variability. considering that the upper airway is often the site of greatest airflow restriction (i.e. snoring), a potential sudden rise in autonomic sympathetic nerve activity in sensory afferent fibers from the oropharynx should be the first to communicate the airflow reduction to brainstem. this theory is supported by the investigators' preliminary data and those in other reports. oral appliance (oa) therapy that prevents snoring in conjunction with a mouth shield should simultaneously facilitate an open airway and prevent mouth breathing. the combination effect is expected to decrease vagus nerve motor efferent activity to the esophagus, facilitate nasal breathing, reduce sympathetic tone, promote stable sleep and increase hrv(heart rate variability). in patients with af, the mytap + ms intervention is likely to also facilitate putatively effective medical therapies, reduce noxious af triggers, and maintain normal oral bacterial flora levels and cardiac functioning.

Eligibility criteria:
inclusion criteria: * pre-qualified for ablation af intervention * af \> 1 documented episode in a 24-hour electrocardiogram (ecg) holter examination or implanted af monitor in the previous 1 month prior to study enrollment; \[af episode defined as at least 12 hours duration\] * at least 8 teeth per arch to support oa device * use of continuous positive air pressure (cpap)therapy and willingness to switch to oa use * willing and able to provide verbal and written informed consent * ability to understand how to apply and utilize the sleep recorder and the oa device exclusion criteria: * patients with implantable cardiac rhythm device \[pacemakers or internal cardiac device (icds)\] or cardiopulmonary disease \[heart failure, chronic obstructive pulmonary disease (copd), ventricular dysrhythmia\] * unable or unwilling to complete the study demands and schedule * comorbidities of other sleep disorders other than osa * no active temporomandibular joint disorders (tmd) or jaw muscle pain, or morphological airway abnormalities * pre-existing difficulty swallowing; throat or neck related health issues; endocrine dysfunction; severe psychiatric and neurological disorders; intellectually disabled; handicaps limiting sleep position * previous oa therapy or restrictions in jaw opening * prior ablation of af, myocardial infarction (mi), stroke or decompensation of heart failure within the last six months, untreated overt hyper- or hypothyroidism * commencement of new anti-arrhythmic drug since last monitor check * pharmacological dependency * concomitant use of hypnotic agents or other sleep aids, nicotine or alcohol intake * mallampati score \> iii * palatine tonsils - grade \> 2 * history of uvulopalatopharyngoplasty (uppp) surgery

Keywords: oral appliance atrial fibrillation sleep apnea mouth shield snoring