Relationships of computed tomography-based small vessel indices of the lungs with ventilation heterogeneity and high transfer coefficients in non-smokers with asthma

Kaoruko Shimizu and colleagues studied 184 asthma patients to investigate the relationship between small pulmonary vessel indices and ventilation heterogeneity in non-smokers and smokers. Using CT and pulmonary function tests alongside AVIEW software for vessel analysis, they found that non-smokers with asthma and low VA/TLC had fewer small vessels (BV5 number) but higher blood volume per vessel (BV5 volume/BV5 number) and increased carbon monoxide transfer coefficients (Kco). These associations were absent in smokers, indicating that smoking-induced vascular damage may impair the redistribution of blood flow in response to ventilation heterogeneity. The study highlights the significance of small vessel dynamics in non-smokers with asthma, where well-ventilated areas receive increased blood volume. The findings suggest the need for further exploration of vascular function in asthma, potentially influencing future treatment strategies. Future studies should include dynamic ventilation-perfusion assessments and larger cohorts to confirm these results, enhancing the understanding of asthma's vascular component.