Glottic configuration in patients with exercise-induced stridor: a new paradigm

Objectives/hypothesis: Paradoxical vocal fold motion and exercise-induced paradoxical vocal fold motion (EIPVFM) are two related conditions that do not have definitive diagnostic criteria. Much of the EIPVFM literature describes patients with characteristic physiologic findings of severe upper airway obstruction or obvious airflow limitation in the clinical context of exertional dyspnea with audible stridor. The objective of this study was to highlight a group of patients who demonstrate important clinical findings of EIPVFM (exertional dyspnea with audible stridor) without simultaneously definitive physiologic findings (mild glottic adduction and normal flow volume loops).

Study design: Retrospective medical record review.

Methods: We reviewed the records of 150 patients who performed continuous laryngoscopy during exercise for inclusion in a case series. We excluded patients for technical (incomplete records) and physiologic (extremes of disease severity) reasons. Three blinded physicians (practicing in laryngology, pulmonology, and allergy/immunology) independently evaluated isolated audio tracks, video tracks, and flow volume loops of the remaining patients for the presence or absence of stridor, the glottic configuration, and the presence or absence of inspiratory limitation on exercise flow volume loops at peak work capacity.

Results: Exercise laryngoscopy and flow volume loops were fully evaluated for 23 patients. Five patients with exertional dyspnea were unanimously described as having audible stridor, open glottic configuration, and normal flow volume loops.

Conclusions: EIPVFM can occur in the absence of widely recognized confirmatory physiologic measures. Improved quantitative metrics are needed to better characterize patients with EIPVFM.

Level of evidence: 4.