Changing predictors of postoperative mortality in acute type A aortic dissection. Is only coronary artery compromise significant?

OBJECTIVES: Rapid emergency transport and early diagnosis and surgical treatment for acute type A aortic dissection have improved postoperative survival, which has, however, plateaued at about 80%. End-organ malperfusion is regarded as a strong predictor of postoperative mortality, replacing factors such as cardiac tamponade complications, aortic rupture, and left ventricular dysfunction due to aortic insufficiency. It is thus important to reevaluate risk factors for surgical death to assess current therapeutic strategies.
METHODS: We statistically analyzed potential risk factors for perioperative death in 88 patients undergoing surgical repair for type A aortic dissection between January 1990 and December 1999.
RESULTS: Univariate analysis showed that cardiopulmonary arrest (adjusted odds ratio: 13.78; p < 0.01) and malperfusion of more than 1 vital organ (adjusted odds ratio 4.97, p < 0.01), especially myocardial ischemia due to coronary artery dissection (adjusted odds ratio 3.21, p < 0.05), significantly increased the likelihood of operative death. Multivariate logistic regression analysis showed only cardiopulmonary arrest (p < 0.01) and concomitant coronary artery bypass grafting necessitated in cases complicated by evolving myocardial infarction (p < 0.05) to be independent predictors of postoperative mortality.
CONCLUSION: Preoperative complication from coronary dissection was the most important predictor of early postoperative mortality in this series. In such cases, rapid surgical intervention before myocardial infarction develops is vital to saving lives.