Harvard Catalyst Profiles

American Heart Association

Investigating Upper Airway Collapse Patterns and Pharyngeal Muscle Function in Obstructive Sleep Apnea

Role Description: Obstructive sleep apnea (OSA) is a highly prevalent disorder characterized by repeated upper airway collapse during sleep, leading to recurrent hypoxia, and ultimately increased cardiovascular disease risk. A key factor in OSA pathophysiology is ineffective dilator muscle function: Indeed, one of the most perplexing observations is that many patients have OSA despite potent activation of the largest dilator muscle (“genioglossus”. GG), for reasons that are unclear. We hypothesize that “low muscle effectiveness” is the consequence of different airway structures causing collapse in different patients: Specifically, with “lateral wall collapse”, forward movement of GG will have minimal functional impact. Low muscle effectiveness also has major implications for reduced efficacy of a recent surgical therapy called hypoglossal nerve stimulation (HGNS), which relies on genioglossus effectiveness for its therapeutic effect, but only resolves OSA in about two-thirds of patients. We hypothesize that low muscle effectiveness is an important but unrecognized contributor to HGNS failure.

Role: Principal Investigator