Abstract：Objective: To evaluate the clinical application of MRI, particularly the contrast enhanced magnetic resonance angiography(CE-MRA) in the treatment of atrial fibrillation by radiofrequency catheter ablation. Methods: The MRI materials of 23 patients(16 men, 7 women; age from 38 to 75 years; mean age 60.4 years) with atrial fibrillation underwent radiofrequency ablation were analyzed retrospectively. The demonstration of pulmonary veins and left atrium, the variation degree of the pulmonary veins were depicted. Results: All MRI images can be used to demonstrate the left atrium and pulmonary veins clearly. The majority of patients(n=19, 82%) had two ostia on both sides of the left atrium(classical type). Four patients(18%) had variations of pulmonary veins. Among them 3(13%) had one common ostium on the left side of the left atrium. One(4%) had three veins on the left side. Of the 3 patients with a common ostium on the left side, 1 patient had three veins on the right side. The demonstration rate of pulmonary ostium by CE-MRA(100%) is higher than that of Double-IR(61.5%) and FIESTA(71.4%). Conclusion: MRI and CE-MRA is the most useful imaging modality to demonstrate the pulmonary veins. It can provide a valuable road map and precise data of pulmonary veins in the treatment of atrial fibrillation by radiofrequency catheter ablation.
2008, Vol. 19 
