title: Allogeneic blood transfusion requirements after minimally invasive versus conventional aortic valve replacement: a risk-adjusted analysis.
abstract: BACKGROUND
  Aortic valve replacement (AVR) through a partial sternotomy (mini-AVR) has been suggested to significantly reduce postoperative morbidity compared with conventional AVR. This study sought to investigate whether mini-AVR patients require fewer transfusions than patients who had conventional AVR.
  
  
  METHODS
  Of 511 patients who had AVR, 56 had mini-AVR and 455 had conventional AVR. A matched-case logistic regression analysis was used to adjust for these imbalances between groups.
  
  
  RESULTS
  No patient in the mini-AVR cohort required conversion to a conventional AVR. Cardiopulmonary bypass time was longer in the mini-AVR group compared with the conventional AVR group, with a median of 102 minutes (range, 78 to 119 minutes) versus 75 minutes (range, 61 to 96 minutes; p < 0.01) in the conventional AVR group. A total of 31 patients (55%) in the mini-AVR group and 336 patients (74%) in the conventional sternotomy group required transfusions during their hospital stay (p < 0.01). After adjusting for differences in preoperative risk factors, year of operation, and surgeon, by matching on propensity score, the differences were not statistically significant (odds ratio = 0.84, 95% confidence interval = 0.40 to 1.75, p = 0.63).
  
  
  CONCLUSIONS
  Mini-AVR produces better wound cosmesis and less surgical trauma but requires more time to perform. Matched-case analysis failed to show a significant difference in blood transfusion requirements after mini-AVR compared with the conventional AVR approach.
authors.affiliation: Section of Cardiac Surgery, Department of Surgery, Georgetown University Hospital, Washington, DC 20007, USA.
authors.forename: Sotiris C
authors.initials: SC
authors.lastname: Stamou
authors.forename: Emmanouil I
authors.initials: EI
authors.lastname: Kapetanakis
authors.forename: Robert
authors.initials: R
authors.lastname: Lowery
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Jablonski
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Frankel
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Corso
mesh_terms: D000368:Aged; D001021:Aortic Valve / Q000601:surgery*; D001803:Blood Transfusion / Q000379:methods*; D006348:Cardiac Surgical Procedures / Q000379:methods; D002315:Cardiopulmonary Bypass; D005260:Female; D006350:Heart Valve Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures; D013997:Time Factors; D016896:Treatment Outcome