title: Postoperative myocardial ischemia in thoracic aortic aneurysms.
abstract: BACKGROUND
  To determine the incidence and predictors of postoperative myocardial ischemia in non-coronary risk patients undergoing surgery for thoracic aortic aneurysms.
  
  
  METHODS
  
  
  
  METHODS
  a prospective, observational study.
  
  
  METHODS
  a general intensive care unit in a university hospital.
  
  
  METHODS
  twenty patients without ischemic heart disease, scheduled for elective surgical repair of thoracic or thoracoabdominal aortic aneurysms.
  
  
  METHODS
  all patients underwent aortic replacement with prosthetic graft and routine postoperative care. Patients who developed myocardial ischemia received an infusion of coronary vasodilators.
  
  
  RESULTS
  ECG episodes of myocardial ischemia were defined as reversible ST-segment changes of either >1 mm of depression or >2 mm of elevation at the J point. All patients survived operation. Eleven patients (ischemia group) developed myocardial ischemia, and 9 patients did not (non-ischemia group). These episodes were transient in 8 cases, but lasted longer than 3 days in 3 cases. In univariate analysis of perioperative factors between the two groups, the use of total cardiopulmonary bypass (p<0.01), the cardiac index at ICU admission (p<0.05), and the incidence of pre-existent hypertension (p<0.05) were significantly different. Multiple regression analysis identified the use of total cardiopulmonary bypass as the only predictor of myocardial ischemia.
  
  
  CONCLUSIONS
  The use of total cardiopulmonary bypass is predictive of perioperative myocardial ischemia in surgery for thoracic aortic aneurysms, probably due to the production of proinflammatory cytokines by systemic ischemia and reperfusion. Prophylactic use of coronary vasodilators may be validated in these cases.
authors.affiliation: Department of Cardiovascular Surgery, Hokkaido University Hospital, Sapporo, Japan. sasakish@med.hokudai.ac.jp
authors.forename: S
authors.initials: S
authors.lastname: Sasaki
authors.forename: K
authors.initials: K
authors.lastname: Yasuda
authors.forename: S
authors.initials: S
authors.lastname: Nanzaki
authors.forename: S
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Y
authors.initials: Y
authors.lastname: Morimoto
authors.forename: S
authors.initials: S
authors.lastname: Gando
authors.forename: O
authors.initials: O
authors.lastname: Kemmotsu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017545:Aortic Aneurysm, Thoracic / Q000601:surgery*; D019917:Blood Vessel Prosthesis Implantation; D002315:Cardiopulmonary Bypass; D003422:Critical Care; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000209:etiology*; D011183:Postoperative Complications / Q000209:etiology*; D011446:Prospective Studies; D012307:Risk Factors