title: The single-centre experience of the supra-arch chimney technique in endovascular repair of type B aortic dissections.
abstract: OBJECTIVE
  We summarised the data performed at our centre to evaluate the feasibility of the chimney technique in type B aortic dissections (ADs) with supra-aortic vessel involvement.
  
  
  METHODS
  From September 2006 to December 2011, 34 thoracic endovascular aortic repairs (TEVARs) for ADs were performed combined with reconstruction of the arch branches with chimney stents (innominate artery, IA, n = 3; left common carotid artery, LCCA, n = 8; left subclavian artery, LSA, n = 23). Indications for these chimney stents included an inadequate proximal landing zone (<1.5 cm); high surgical-risk patients who are not suitable for open repair or hybrid procedures; and emergent endovascular repair of ADs. The series consisted of 13 acute, 12 sub-acute and 9 chronic cases. The right common carotid-left common carotid-left subclavian artery bypasses were performed in the IA chimney cases to reserve an adequate cerebral perfusion from the LCCA and left vertebral artery, while the left common carotid-left subclavian artery bypasses were performed in the cases having dominant left vertebral arteries. All the TEVARs, chimney stents and bypasses were performed as a single stage. Follow-ups were performed at 3, 6 and 12 months, and yearly thereafter.
  
  
  RESULTS
  Endografts were deployed in Zone 0 (n = 3, 9%), Zone 1 (n = 8, 24%) and Zone 2 (n = 23, 67%). Twenty-five (74%) balloon-expandable and 9 (26%) self-expanding stents were used, of which seven (21%) were covered and 27 (79%) were bare stents. The technical success rate was 82% (28/34). Immediate type I endoleaks were observed in five patients (5/34, 15%), all of which underwent bare chimney-stent repairs. Three self-expanding chimney stents were compressed by endografts and another balloon expandable stent was deployed inside the first one. Five patients underwent surgical bypasses (RCCA-LCCA-LSA, n = 3; LCCA-LSA, n = 2). Perioperative morbidity included one ST-elevation myocardial infarction. No perioperative death or stroke was observed. The mean follow-up was 16.3 months (range, 3-60 months). Primary patency was maintained in all the chimney stents as well as the surgical bypasses. No stent fracture or recurrent chimney-related endoleak was observed during the follow-up period.
  
  
  CONCLUSIONS
  In repairs for type B ADs, the chimney technique provides a minimally invasive way of preserving flow to the arch branches combined with a favourable mid-term outcome. The bare stents seemed to be related to a higher probability of the immediate type I endoleaks. A balloon-expandable stent should be regarded as the first choice due to its greater radial strength.
authors.affiliation: Department of Vascular and Endovascular Surgery, 301 General Hospital of PLA, 28#, Fuxing Road, Beijing 100853, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhu
authors.forename: W
authors.initials: W
authors.lastname: Guo
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.forename: X
authors.initials: X
authors.lastname: Jia
authors.forename: J
authors.initials: J
authors.lastname: Xiong
authors.forename: L
authors.initials: L
authors.lastname: Wang
mesh_terms: D000208:Acute Disease; 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 / Q000379:methods*; D002908:Chronic Disease; D057867:Endoleak / Q000209:etiology; D057510:Endovascular Procedures / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000209:etiology; D011474:Prosthesis Design; D012189:Retrospective Studies; D012307:Risk Factors; D015607:Stents; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome