Lung function in relation to haemodynamic status after atrial redirection for transposition of the great arteries

To assess the interplay between haemodynamic sequelae and lung function after atrial redirection for transposition of the great arteries, we investigated 15 Mustard (age 12.0-22.0 years), and 15 Senning patients (age 7.2-12.1 years). As diagnosed at cardiac catheterization and ultracardiography, 16 (11 Mustard) had major haemodynamic sequelae, including systemic ventricle dysfunction, pulmonary hypertension, pulmonary venous obstruction, systemic venous obstruction and atrial septal defects. Static and dynamic lung volumes, ventilation distribution and diffusion capacity were assessed by body plethysmography, spirometry, the single-breath nitrogen test (N2slope) and the single-breath method for diffusion capacity (DLCO) respectively. Apart from DLCO, our own reference values were used for comparison. We found small lung volumes, a high functional residual capacity, a high N2slope and a low DLCO. Tests of > 2SD in the abnormal direction were more prevalent in the Mustard group (P = 0.06) and significantly more prevalent in patients with pulmonary hypertension. Six had normal lung function tests, 15 had unclassified abnormalities, three had small lungs and three had central airway obstruction. Peripheral airway obstruction was only present in three of four subjects with moderate or severe pulmonary hypertension. The study confirms some previous reports indicating a high frequency of lung function abnormalities in these patient groups and discusses a possible relationship to haemodynamic status.