title: Impact of Oversizing on the Risk of Retrograde Dissection After TEVAR for Acute and Chronic Type B Dissection.
abstract: OBJECTIVE
  To find a suitable rate of thoracic stent-graft oversizing by exploring its association with the occurrence of retrograde type A dissection (RTAD) after thoracic endovascular aortic repair (TEVAR) for type B aortic dissection.
  
  
  METHODS
  From January 2013 to June 2014, 203 patients (mean age 55 years; 167 men) with type B aortic dissection underwent TEVAR. The mean rate of oversizing at the proximal landing zone was 10% (range 0%-32%). Patients were stratified into 2 groups based on the degree of oversizing: ≤5% (n=105, mean 1.2%±1.5%) and >5% (n=98, mean 18.5%±2.8%). TEVAR-related complications, including RTAD, stent migration, and type I endoleaks, were analyzed.
  
  
  RESULTS
  There were no significant differences in the preoperative proximal landing zone diameters between the groups (31.1 mm for the ≤5% group vs 31.8 mm for the >5% group, p=0.229). The incidence of type I endoleaks over a mean follow-up 15.1±6.4 months was 5.4% [6 (5.7%) in the ≤5% group vs 5 (5.1%) in the >5% group, p=0.847]. The stent migration rate was low in both groups (1% vs 2%, respectively; p=0.521). The occurrence of RTAD [0 in the ≤5% group vs 11 (11.2%) in the >5% group] was significantly associated with the rate of oversizing (p<0.001).
  
  
  CONCLUSIONS
  The early and midterm outcomes of this study demonstrate that ≤5% oversizing may be a suitable option for thoracic endografts used to treat type B dissection. The smaller rate of oversizing can lower the incidence of RTAD without increasing stent migration or type I endoleak rates.
authors.affiliation: Department of Vascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, P.R. China.
authors.forename: Lei
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Vascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, P.R. China.
authors.forename: Simeng
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Department of Vascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, P.R. China luqs@xueguan.net.
authors.forename: Qingsheng
authors.initials: Q
authors.lastname: Lu
authors.affiliation: Department of Vascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, P.R. China.
authors.forename: Zaiping
authors.initials: Z
authors.lastname: Jing
authors.affiliation: Department of Vascular Surgery, Changhai Hospital, Second Military Medical University, Shanghai, P.R. China.
authors.forename: Suming
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Department of Imaging, Changhai Hospital, Second Military Medical University, Shanghai, P.R. China.
authors.forename: Bing
authors.initials: B
authors.lastname: Xu
mesh_terms: D000328:Adult; D000368:Aged; D000784:Aortic Dissection / Q000000981:diagnostic imaging / Q000601:surgery*; D017545:Aortic Aneurysm, Thoracic / Q000000981:diagnostic imaging / Q000601:surgery*; D001027:Aortography / Q000379:methods; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D000072226:Computed Tomography Angiography; D057867:Endoleak / Q000209:etiology / Q000517:prevention & control; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation*; D005260:Female; D005548:Foreign-Body Migration / Q000209:etiology / Q000517:prevention & control; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology / Q000517:prevention & control*; D011474:Prosthesis Design; D012189:Retrospective Studies; D012307:Risk Factors; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome
keywords: Stanford type B aortic dissection; aortic dissection; endoleak; migration; retrograde aortic dissection; stent-graft oversizing; thoracic endovascular aortic repair; type I endoleak