Bronchoconstriction in asthma leads to heterogeneous ventilation and the formation of large and contiguous ventilation defects in the lungs. However, the regional adaptations of pulmonary perfusion (Q) to such ventilation defects have not been well studied.
Department of Medicine (Pulmonary and Critical Care Unit and General Medicine Unit), Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA. rharris@partners.org
