Are there correlations between lung volume and exercise capacity in children and adolescents with native Ebstein's anomaly?

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background Patients with Ebstein’s Anomaly (EA) represent a wide clinical range with patients needing surgery in infancy and others needing no surgery throughout life. Exercise capacity in EA is often impaired. However, lung function is rarely investigated. Purpose This study examines lung volumes in native EA and their correlation with exercise capacity. Methods This retrospective study investigated 35 children with native EA (14 ± 4 years, 17 female), who underwent a cardiopulmonary exercise test (CPET) including spirometry to examine peak oxygen uptake (peakV’O2), forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1) and its ratio (FEV/FVC). Percentage in peakV’O2 <80% represents a reduced exercise capacity, and values <60% are defined as impaired. Z-scores below -1.64 categorize restrictive (FVC) or obstructive (FEV1/FVC) patterns. To analyse correlations between CPET and lung volumes Spearman’s rank test was performed. Results Reduced exercise capacity was found in 17 children (47%), and further seven (20%) children showed impaired exercise capacity. Seven patients (20%) had a restrictive lung volume pattern and three patients (9%) showed obstructive patterns. One patient showed both. Eleven (92%) patients with an impaired lung function had at least a reduced exercise capacity with a median of 64 [53;73] %predicted. Lung volumes correlate significantly with %peakV’O2 (z-FVC: r=0.500, p=0.002 and z-FEV1: r=0.443, p=0.008). Conclusions Most young patients with native EA have impaired results in exercise capacity and a third has reduced lung volumes. Low lung volumes correlate with worse exercise capacity. Thus, the lung function should also be taken into consideration when looking at the performance of these and medical aftercare.