Accuracy of computed tomography in detection of great vessel stenosis or hypoplasia before superior bidirectional cavopulmonary connection: Comparison with cardiac catheterization and surgical findings

Summary Background Cardiac catheterization is the gold-standard modality for investigation of cardiovascular morphology before bidirectional cavopulmonary connection, but requires general anaesthesia and is associated with procedural risk. Aims To assess the diagnostic accuracy and safety of computed tomography in diagnosing great vessel stenosis/hypoplasia compared with cardiac catheterization and surgical findings. Methods Twenty-seven patients (10 after Norwood stage I) underwent computed tomography before surgery between January 2010 and June 2016; 16 of these patients also underwent cardiac catheterization. Proximal and distal pulmonary artery, aortic isthmus and descending aorta measurements, radiation dose and complications were compared via Bland-Altman analyses and correlation coefficients. Results The accuracy of computed tomography in detecting stenosis/hypoplasia of either pulmonary artery was 96.1% compared with surgical findings. For absolute vessel measurements and Z-scores, there was high correlation between computed tomography and angiography at catheterization ( r  = 0.98 for both) and a low mean bias (0.71 mm and 0.48; respectively). The magnitude of intertechnique differences observed for individual patients was low (95% of the values ranged between −0.9 and 2.3 mm and between −0.7 and 1.7, respectively). Four patients (25%) experienced minor complications from cardiac catheterization, whereas there were no complications from computed tomography. Patients tended to receive a higher radiation dose with cardiac catheterization than with computed tomography, even after exclusion of interventional catheterization procedures (median 2.5 mSv [interquartile range 1.3 to 3.4 mSv] versus median 1.3 mSv [interquartile range 0.9 to 2.6 mSv], respectively; P  = 0.13). All computed tomography scans were performed without sedation. Conclusions Computed tomography may replace cardiac catheterization in identification of great vessel stenosis/hypoplasia before bidirectional cavopulmonary connection when no intervention before surgery is required. Computed tomography carries lower morbidity, can be performed without sedation and may be associated with less radiation.