Restrictive bare stent prevents stent graft induced distal re-dissection after TEVAR for type B aortic dissection

Abstract

Objectives To prevent stent graft induced distal re-dissection (SIDR) after endovascular repair for complicated Stanford type B aortic dissection.Methods From April 1997 to March 2010,674 type B aortic dissections patients were treated by TEVAR at our center.The inclusion criteria for this study had two parts:patients were primarily treated by TEVAR; the estimated mismatch rate (ratio of the distal diameter of the stent graft to the long diameter of the true lumen) was greater than 120％.A total of 465 patients were included in this two-arm study.Results A total of 311 patients were treated with standard TEVAR and 154 patients with TEVAR + restrictive bare stent (RBS).The preoperative mismatch rate (counted by the preoperative long diameter of true lumen at the level of intended distal end of the stentgraft) of the SIDR was significantly higher than that of the non-SIDR [(193 ± 55) ％ vs (132 ± 10) ％,P ＜0.05].The follow-up mismatch rate of SIDR was significantly higher than non-SIDR (145 ±35 vs 120 ± 16,P ＜0.05).Compared with the standard TEVAR,TEVAR + RBS was with lower incidence of SIDR (0％ vs 2.9％,P =0.033) and less secondary intervention (3.9％ vs 9.3％,P =0.040).The placement of RBS significantly expanded the true lumen at the level of descending aorta with narrowest true lumen and at the level of distal end of stent-graft.Conclusions The mismatch between the distal diameter of stent-graft and the diameter of the compressed true lumen seems to contribute to the occurrence of SIDR.Restrictive bare stent,as an adjunctive technique to TEVAR,reduces the incidence of SIDR. Key words: Postoperative complications; Universal precautions; Aortic dissection ; Endovascular procedure