Excessive Dynamic Airway Collapse (EDAC) during exercise can result in exertional dyspnea in a person who may otherwise be perfectly healthy.

Airway collapse may be associated with tracheomalacia, COPD and asthma.


Clinical symptoms may include:

(1) exertional dyspnea with the absence of dyspnea at rest

(2) exertional syncope

(3) focal expiratory wheezing during exercise

(4) variable chronic cough


Studies during expiration will demonstrate collapse in an airway:

(1) During bronchoscopy functional collapse of a large airway may be observed.

(2) CT imaging shows narrowing of a large airway during expiration.


A firm diagnosis of pure EDAC requires exclusion of alternative diagnoses affecting the airways or lungs.

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