Longitudinal Analysis of Ventilation Perfusion Mismatch in Congenital Diaphragmatic Hernia Survivors

Objective To determine the natural history of pulmonary function for survivors of congenital diaphragmatic hernia (CDH). Study design This was a retrospective cohort study of survivors of CDH born during 1991-2016 and followed at our institution. A generalized linear model was fitted to assess the longitudinal trends of ventilation (V), perfusion (Q), and V/Q mismatch. The association between V/Q ratio and body mass index percentile as well as functional status was also assessed with a generalized linear model. Results During the study period, 212 patients had at least one V/Q study. The average ipsilateral V/Q of the cohort increased over time (P < .01), an effect driven by progressive reduction in relative perfusion (P = .012). A higher V/Q ratio was correlated with lower body mass index percentile (P < .001) and higher probability of poor functional status (New York Heart Association class III or IV) (P = .045). Conclusions In this cohort of survivors of CDH with more severe disease characteristics, V/Q mismatch worsens over time, primarily because of progressive perfusion deficit of the ipsilateral side. V/Q scans may be useful in identifying patients with CDH who are at risk for poor growth and functional status.