Does the airway circulation influence airflow obstruction in asthma?

The airway wall is thickened in asthma and the airway microvasculature participates in the remodelling. It has been assumed but not convincingly demonstrated that the remodelled airway vasculature has a mechanical role in asthma-associated airflow obstruction by contributing to the thickening of the airway wall and narrowing of the airway. This review examines the literature providing information in support of and against this assumption and raises questions about therapeutically targeting the airway circulation directly in patients with asthma.