Inhomogeneity of ventilation in smokers and mild COPD assessed by the ratio of alveolar volume to total lung capacity
Background: Previous studies have shown that the ratio between alveolar volume (VA) and total lung capacity (TLC) reflects ventilation heterogeneity in subjects with chronic obstructive pulmonary disease (COPD). However, the ratio and its correlation to respiratory symptoms had to our knowledge not previously been investigated in subjects with mild chronic airflow obstruction or without airflow ob