title: The preferred approach for mitral valve surgery after CABG: right thoracotomy, hypothermia and avoidance of LIMA-LAD graft.
abstract: OBJECTIVE
  An alternative to avoid redo sternotomy in patients with patent left internal mammary artery-left anterior descending coronary artery (LIMA-LAD) grafts undergoing mitral valve surgery is right thoracotomy with moderate-deep hypothermia (approximately 20 degrees C) and fibrillatory arrest without aortic cross-clamping. Few reports exist which directly compare re-sternotomy and right thoracotomy.
  
  
  METHODS
  Between July 1992 and February 2000, 47 patients (39 males, eight females; median age 66 years; range: 41-83 years; 41 in NYHA class III or IV) with patent LIMA-LAD grafts underwent mitral valve surgery. Thirty-seven patients were approached through a right thoracotomy with moderate-deep hypothermia (median 20 degrees C) and fibrillatory arrest (right thoracotomy group), and 10 were approached through a re-sternotomy, with aortic cross-clamping and cardioplegic arrest. The median ejection fraction was 42% (range: 20-71%). Univariate analysis was used to determine predictors of outcome, as well as to evaluate differences in characteristics between groups.
  
  
  RESULTS
  Operative mortality (OM) and perioperative myocardial infarction for the entire cohort was 11% and 10%, respectively, and there were no inter-group differences. No preoperative characteristics were associated with OM. Two LIMA-LAD graft injuries occurred in the re-sternotomy group compared with none in the right thoracotomy group (20% versus 0%, p = 0.04). Transfusion requirements were also greater in the redo sternotomy group (median 7 versus 2 packed red blood cell units, p = 0.04).
  
  
  CONCLUSIONS
  Right thoracotomy with moderate-deep hypothermia and fibrillatory arrest is the preferred approach for reoperative mitral valve surgery after coronary artery bypass grafting in the presence of patent LIMA-LAD grafts. These data suggest that this approach is associated with decreased incidence of LIMA-LAD graft injury, as well as reduced transfusion requirements.
authors.affiliation: Division of Cardiac Surgery, Brigham & Women's Hospital, Boston, Massachusetts 02115, USA.
authors.forename: J G
authors.initials: JG
authors.lastname: Byrne
authors.forename: A N
authors.initials: AN
authors.lastname: Karavas
authors.forename: D H
authors.initials: DH
authors.lastname: Adams
authors.forename: L
authors.initials: L
authors.lastname: Aklog
authors.forename: S F
authors.initials: SF
authors.lastname: Aranki
authors.forename: F
authors.initials: F
authors.lastname: Filsoufi
authors.forename: L H
authors.initials: LH
authors.lastname: Cohn
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001158:Arteries / Q000637:transplantation; D002315:Cardiopulmonary Bypass / Q000401:mortality; D001026:Coronary Artery Bypass / Q000401:mortality; D003324:Coronary Artery Disease / Q000150:complications / Q000401:mortality / Q000601:surgery; D003331:Coronary Vessels / Q000637:transplantation; D005260:Female; D006349:Heart Valve Diseases / Q000150:complications / Q000401:mortality / Q000601:surgery*; D019918:Heart Valve Prosthesis Implantation / Q000401:mortality; D006801:Humans; D007036:Hypothermia, Induced; D008297:Male; D008323:Mammary Arteries / Q000637:transplantation; D008875:Middle Aged; D008943:Mitral Valve / Q000601:surgery*; D011183:Postoperative Complications / Q000209:etiology; D012086:Reoperation; D016019:Survival Analysis; D013908:Thoracotomy / Q000401:mortality; D013997:Time Factors