Morphologic demonstration of corrected transposition of the great arteries and double outlet right ventricle, using magnetic resonance imaging

Seven patients with corrected transposition of the great arteries (cTGA) and six patients with double outlet right ventricle (DORV), aged one month to 17 years (median five years), were studied by magnetic resonance imaging (MRI). ECG-gated MRI was performed by spin-echo imaging at 0.5 tesla. A combination of standard and oblique imaging planes were used. Two-dimensional echocardiography and angiography were performed in all patients, including eight who underwent surgical correction and final diagnosis were based on these findings. MRI findings were compared with the final diagnosis. The coronal images of one patient were unsuitable for analysis. In the remaining patients, MRI results were sufficient to evaluate anomalies. The images were particularly valuable in demonstrating interrelations between the great arteries, the location of ventricular septal defect (VSD), and the anatomy of the subaortic and subpulmonary regions. The anatomical distances between VSD and the aortic valve measured on MRI correlated well with those of the final diagnosis (r=0.92). In patients with cTGA and DORV, MRI can provide accurate information on intracardiac morphology that may contribute to improvement in surgical management. (author)