Comparative evaluation of TEE, conventional MRI and contrast-enhanced 3D breath-hold MRA in the post-operative follow-up of dissecting aneurysms

Purpose: To verify the diagnostic potentialities of conventional magnetic r esonance imaging (MRI), breath-hold 3D contrast enhanced MR angiography (C3 D MRA) and transesophageal echocardiography (TEE) in patients surgically tr eated for type A aortic dissection. Materials and methods: Twenty-nine pati ents (21 males and 8 females), surgically treated for type A aortic dissect ion, were evaluated with MRI using a 1.5 T (GE Horizon Echospeed 8.2) with standard gated SE sequences and breath-hold 3D fast SPGR after intravenous Gd injection (0.2 mmol/kg). 3D MIP reconstruction was obtained. TEE evaluat ion was performed with a HP 2000 system and a biplane 5 MHz probe. The size s of aortic root, distal anastomosis, descending aorta and periprosthetic t hickening were measured. Regional false lumen and aortic branch involvement were also evaluated. Results: Concordance among TEE, conventional MRI and C3D MRA was observed in the evaluation of aortic root (MRI vs. C3D MRA r = 0.93; MRI vs. TEE r = 0.84; C3D MRA vs. TEE r = 0.84) and descending aorta (r = 0.94, 0.91 and 0.92, respectively). The interobserver variability was also very low. Inadequate agreement was observed for distal anastomosis. C3 D MRA was inadequate in the evaluation of periprosthetic thickening; r = 0. 73 was obtained between MRI and TEE. For qualitative data: TEE was inadequa te in the evaluation of the abdominal aorta and branches. C3D MRA depicted supra-aortic vessel involvement in more cases than the other techniques. Co nclusion: C3D MRA is a fast and accurate technique in the evaluation of the endoluminal alterations and involvement of the aortic branches. Convention al MRI allows a direct evaluation of the aortic wall and periaortic tissue. TEE is less accurate in the evaluation of aortic branches and abdominal ao rta.