title: Outcomes of Left Heart Bypass Versus Circulatory Arrest in Elective Open Surgical Descending and Thoraco-abdominal Aortic Repair.
abstract: OBJECTIVE
  To compare early (30 day mortality and major complications) and midterm (survival) outcomes in elective open surgical descending and thoraco-abdominal aortic repair using left heart bypass (LHB) versus hypothermic circulatory arrest (HCA) for organ protection, hypothesising non-inferiority of HCA management.
  
  
  METHODS
  This was a retrospective clinical cohort study with cross sectional follow-up. All elective (n = 90) descending or thoraco-abdominal aortic repairs performed between 2004 and 2015 using either LHB (n = 57) or HCA (n = 33) were included. Pre- and intra-operative variables were evaluated by univariate statistical analysis. Thirty day and follow-up mortality were primary endpoints; major complications were secondary endpoints. Propensity score matching was employed to adjust for selection bias. Kaplan-Meier methods were used to estimate midterm survival.
  
  
  RESULTS
  Overall 30 day mortality was 8/90 (8.9%): 6/57 (10.5%) using LHB vs. 2/33 (6.1%) using HCA, p = .47. Five patients (5.6%) suffered paraplegia: 3/57 (5.3%) using LHB vs. 2/33 (6.1%) using HCA, p = .87. Stroke occurred in 6/57 (11%) vs. 2/33 (6.1%), p = .76; renal failure in 27/57 (47%) vs. 19/33 (58%), p = .90; and respiratory failure in 17/57 (30%) vs. 11/33 (33%), p = .68. In 26 propensity score matched pairs, findings remained unaltered. Total follow-up was 443 patient years (median 4.9 years). Estimated survival was 78% at 1 year and 77% at 5 years in LHB vs. 72% and 67%, respectively, with HCA; there were no significant inter-group differences, before or after propensity score matching.
  
  
  CONCLUSIONS
  In elective descending or thoraco-abdominal aortic repair, no statistically significant differences in 30 day mortality, major complications, or follow-up survival were found when LHB and HCA were compared. These findings remained after propensity score matching.
authors.affiliation: Department of Vascular Surgery, Karolinska University Hospital and Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
authors.forename: C-M
authors.initials: CM
authors.lastname: Wahlgren
authors.affiliation: Department of Vascular Surgery, Karolinska University Hospital and Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Blohmé
authors.affiliation: Department of Cardiothoracic Surgery and Anaesthesia, Karolinska University Hospital and Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Günther
authors.affiliation: Department of Cardiothoracic Surgery and Anaesthesia, Karolinska University Hospital and Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Nilsson
authors.affiliation: Department of Cardiothoracic Surgery and Anaesthesia, Karolinska University Hospital and Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden. Electronic address: Christian.olsson@ki.se.
authors.forename: C
authors.initials: C
authors.lastname: Olsson
mesh_terms: D000368:Aged; D001012:Aorta, Abdominal / Q000000981:diagnostic imaging / Q000601:surgery*; D001013:Aorta, Thoracic / Q000000981:diagnostic imaging / Q000601:surgery*; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D017558:Elective Surgical Procedures; D005260:Female; D006324:Heart Arrest, Induced / Q000009:adverse effects / Q000401:mortality; D018611:Heart Bypass, Left / Q000009:adverse effects / Q000401:mortality; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011183:Postoperative Complications / Q000209:etiology; D057216:Propensity Score; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014656:Vascular Surgical Procedures / Q000009:adverse effects / Q000401:mortality
keywords: Aortic aneurysm; Outcomes; Surgery; Thoraco-abdominal