title: Elephant trunk in a small-calibre true lumen for chronic aortic dissection: cause of haemolytic anaemia?
abstract: OBJECTIVE
  The elephant trunk technique for aortic dissection is useful for reducing false lumen pressure; however, a folded vascular prosthesis inside the aorta can cause haemolysis. The purpose of this study was to investigate whether an elephant trunk in a small-calibre lumen can cause haemolysis.
  
  
  METHODS
  Inpatient and outpatient records were retrospectively reviewed.
  
  
  RESULTS
  Two cases of haemolytic anaemia after aortic surgery using the elephant trunk technique were identified from 2011 to 2013. A 64-year-old man, who underwent graft replacement of the ascending aorta for acute Stanford type A aortic dissection, presented with enlargement of the chronic dissection of the descending aorta and moderate aortic regurgitation. A two-stage surgery was scheduled. Total arch replacement with an elephant trunk in the true lumen and concomitant aortic valve replacement were performed. Postoperatively, he developed severe haemolytic anaemia because of the folded elephant trunk. The anaemia improved after the second surgery, including graft replacement of the descending aorta. Similarly, a 61-year-old man, who underwent total arch replacement for acute Stanford type A aortic dissection, presented with enlargement of the chronic dissection of the descending aorta. Graft replacement of the descending aorta with an elephant trunk inserted into the true lumen was performed. The patient postoperatively developed haemolytic anaemia because of the folded elephant trunk, which improved after additional stent grafting into the elephant trunk.
  
  
  CONCLUSIONS
  A folded elephant trunk in a small-calibre lumen can cause haemolysis. Therefore, inserting an elephant trunk in a small-calibre true lumen during surgery for chronic aortic dissection should be avoided.
authors.affiliation: Department of Cardiovascular Surgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan haruna.araki0401@gmail.com.
authors.forename: Haruna
authors.initials: H
authors.lastname: Araki
authors.affiliation: Department of Cardiovascular Surgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Kitamura
authors.affiliation: Department of Cardiovascular Surgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Horai
authors.affiliation: NTT Medical Center Tokyo, Tokyo, Japan.
authors.forename: Ko
authors.initials: K
authors.lastname: Shibata
authors.affiliation: Department of Cardiovascular Surgery, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan.
authors.forename: Kagami
authors.initials: K
authors.lastname: Miyaji
mesh_terms: D000743:Anemia, Hemolytic / Q000175:diagnosis / Q000209:etiology* / Q000601:surgery; D000784:Aortic Dissection / Q000175:diagnosis / Q000601:surgery*; D001014:Aortic Aneurysm / Q000175:diagnosis / Q000601:surgery*; D001027:Aortography / Q000379:methods; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects* / Q000295:instrumentation*; D002908:Chronic Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D012086:Reoperation; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: Aortic surgery; Haemolysis; Surgical complications