title: Mortality in acute type A aortic dissection: validation of the Penn classification.
abstract: BACKGROUND
  Intraoperative and in-hospital mortality after surgery for acute type A dissection depends largely on preoperative conditions, specifically the presence of localized or generalized ischemia. Recently, the Penn classification of patients with acute type A aortic dissection has been described. The primary aim was to validate the Penn classification and to investigate preoperative variables related to mortality.
  
  
  METHODS
  All consecutive patients operated for acute type A aortic dissection, 1990 to 2009 (n = 360), were included in a retrospective observational study. Univariate and multivariable analyses were used to identify variables related to intraoperative and in-hospital mortality. Propensity scoring was used to adjust for treatment selection bias.
  
  
  RESULTS
  Overall intraoperative mortality was 7% (24 of 360) and in-hospital mortality was 19% (69 of 360). Two hundred nineteen patients (61%) were Penn class Aa (14% in-hospital mortality), 51 (14%) class Ab (24% mortality), 63 (18%) class Ac (24% mortality), and 27 (8%) class Abc (44% mortality), p =0.007. In multivariable analysis, Penn class Ac and Abc were independently related to intraoperative death (odds ratio 5.0 and 5.4, respectively), and Penn class Abc and non-Aa were independently related to in-hospital mortality (odds ratio 3.4 and 2.3, respectively). Concomitant coronary artery bypass grafting, older age, DeBakey type I dissection, and prolonged periods of cardiopulmonary bypass and hypothermic circulatory arrest were also independently associated with mortality.
  
  
  CONCLUSIONS
  The Penn classification of acute type A aortic dissection is purposeful and its continued usage encouraged. Penn class indicating localized or generalized ischemia is independently related to intraoperative and in-hospital mortality.
authors.affiliation: Department of Molecular Medicine and Surgery, The Karolinska Institute, Stockholm, Sweden. christian.olsson@ki.se
authors.forename: Christian
authors.initials: C
authors.lastname: Olsson
authors.forename: Carl-Gustaf
authors.initials: CG
authors.lastname: Hillebrant
authors.forename: Jan
authors.initials: J
authors.lastname: Liska
authors.forename: Ulf
authors.initials: U
authors.lastname: Lockowandt
authors.forename: Per
authors.initials: P
authors.lastname: Eriksson
authors.forename: Anders
authors.initials: A
authors.lastname: Franco-Cereceda
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000784:Aortic Dissection / Q000145:classification* / Q000401:mortality / Q000601:surgery; D017545:Aortic Aneurysm, Thoracic / Q000145:classification* / Q000401:mortality / Q000601:surgery; D005260:Female; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D007432:Intraoperative Period; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D012189:Retrospective Studies; D018570:Risk Assessment / Q000379:methods*; D016019:Survival Analysis; D015996:Survival Rate / Q000639:trends; D013548:Sweden / Q000453:epidemiology; D014656:Vascular Surgical Procedures / Q000401:mortality*; D055815:Young Adult