Implantation sequence modification averts distal stent graft-induced new entry after endovascular repair of Stanford type B aortic dissection

Objective: This study investigated predisposing factors of distal stent graft-induced new entry (SINE). Methods: Data from November 2006 to May 2012 were abstracted retrospectively from the records of 73 patients with complicated type B aortic dissection who had received stent graft treatment in our institution. Diameters of the true and false lumen, area and circumference of the true lumen, prestent and poststent oversize, taper, and mismatch ratio were recorded and analyzed to see if there were any significant differences between the SINE (n = 19) and non-SINE (n[ 54) population and between those in whom the initial endograft was inserted from the proximal thoracic aorta (n [ 49) or the distal thoracic aorta (n = 24). Results: A distal-first sequence of stent graft deployment produced significantly fewer instances of distal SINE. The area oversizing ratio of the distal end of the stent graft was greater in the SINE vs non-SINE groups (3.76 +/- 1.7 vs 2.63 +/- 2.57; P = .002) and in the proximal-first vs distal-first deployment sequence groups (3.67 +/- 2.57 vs 1.39 +/- 0.90; P <.001). Conclusions: Minimizing the preprocedure distal oversizing ratio with a distal small graft-first procedure could reduce the risk of late distal SINE for Stanford type B aortic dissection. Furthermore, the area ratio is a potentially more sensitive modality for size assessment and prediction of distal SINE occurrence.