Midterm Outcomes of Thoracic Aortic Stent-Grafts: Complications and Imaging Techniques

Abstract

Purpose: To evaluate the midterm outcomes of thoracic aortic stent-grafting and the performance of computed tomographic angiography (CTA), radiography, and magnetic resonance angiography (MRA) in endograft surveillance. Methods: Forty-seven patients with traumatic thoracic aortic ruptures (n=16), aneurysms (n=14), false aneurysms (n=3), penetrating ulcers (n=3), and dissections (n=11) treated with stent-grafts were monitored in follow-up using chest radiography and CTA in all patients and MRA in 23 patients. Two perpendicular maximal aortic diameters, the sum of these diameters, and the elliptical cross-sectional area were determined and compared to baseline for the entire group and in subgroup analyses according to lesion type. CTA, MRA, and radiography were compared for their ability to detect endoleak, monitor stent-graft configuration, and measure aortic diameters. Results: The mortality rate was 8.5%. Severe complications were observed in 14.8% (6% neurological complications); 12 (25.5%) patients had primary endoleaks. Over a mean 11-month follow-up (range 0.25–46 months), the aortic diameters decreased for all patients without endoleak (p<0.001). In the diameter/area subgroup analyses, only the traumatic rupture cohort demonstrated significant decreases in all 4 measurements. CTA and MRA measurements correlated well, but chest radiography was superior to both for visualizing stent-graft shape. In terms of endoleak detection, MRA missed only 1 (12.5%) endoleak (type II) seen on CTA; there were no false positive results with MRA. Conclusions: Morbidity and mortality observed after thoracic stent-grafting are acceptable. Radiography is better for monitoring stent-graft conformation, while CTA provides the best overall morphological information. The performance of MRA in endoleak detection is encouraging.