Objective To evaluate the diagnostic value of MRI in complicated congenital heart disease, comparing with echocardiography and x-ray cardio-angiography.
Methods 20 patients with complicated or complex congenital heart disease (male 12, female 8, mean age 17.8 y, ranging from 3–46 y) underwent MR examination. A wireless vector ECG-gating was used for triggering; all the sequences were applied with breath hold or free breathing. Turbo spin echo and multiple gradient echo sequences including FLASH (fast low angle shot) and TrueFISP (true fast imaging with steady-state precession.) with TSENSE (adaptive sensitivity encoding incorporating temporal filtering) and TREAT (time resolved echo-shared technique) were used to evaluate the morphology, function, flow status of the heart. MR findings were compared with the results of echocardiography and x-ray cardio-angiography.
Results All the examination were accomplished successfully and diagnostic MR images were obtained satisfactory. The mean total scan time was 38 min ranging from 29∼55 min. According to the main malformation diagnosed by MRI, double-outlet of right ventricle (DORV) were 11 cases, single ventricle were 3 cases, function-corrected transposition of great arteries were 2 cases, endocardial cushion defect, interruption of aortic arch, coarctation of the aorta and pulmonary atresia was 1 case, respectively. The total coincidence was 95% comparing with cardio-angiography, while the echocardiography was 75%. It is difficult for x-ray cardio-angiography to evaluate the atrio-rentriculor valve in 25% cases, while MR can clearly and precisely show the number, morphology and function of the valves in all cases. There is 20% of the cases that traditional x-ray cardio-angiography cannot demonstrate the connection of ventricular-great arteries, or the main pulmonary artery and its main branches because of anatomy overlapping, tolerance of the patients and skill of catheterisation, while MR provide important complementarities for these cases.
Conclusion Combined with new robust techniques, MRI can provide a comprehensive evaluation of complicated congenital heart disease including morphology, function, and flow and so on. With some characteristics of both echocardiography and x-ray angiography, in some aspects MRI is even better than x-ray angiography and can offer important supplemental information.