Abstract

Objective: Some Institutions have reported improved results with acute type A aortic dissection repaired in the current era. Aim of the present study was to identify possible risk factors influencing surgical results of emergency treatment of pts with type A acute aortic dissection since a uniform surgical approach and perioeperative management have been introduced.

Methods: Between 1/1990 and 12/1997, 122 pts (86 males and 36 females; mean age 60 ± 12 yrs) underwent emergency repair of acute type A aortic dissection using a standardized surgical approach. Seventy-four (61%) pts required isolated replacement of the dissected ascending aorta, 27 (22%) required additional replacement of the aortic arch and 21 (17%) required total aortic root replacement. Surgical outcome was measured in terms of operative mortality and morbidity. Results of pts presenting with preoperative complications (C) (cardiac tamponade, cerebral stroke, shock, acute myocardial infarction, acute anuria or visceral ischemia) were compared with those of uncomplicated (U) cases and with a calculated expected risk (E) of operative mortality, within each of the 8 years of experience. Sixteen preoperative and 18 perioperative variables were analyzed to identify possible risk factors for morbidity and mortality.

Results: Fifty-seven pts (47%) sustained preoperative complications (C) and 65 (53%) did not (U). Overall operative mortality (U + C) was 22% with cardiogenic shock as the most frequent cause of hospital death (12 pts; 44%). The type or surgical procedure employed did not influence operative mortality which was 40% and 6% in C and U cases, respectively (p = 0.00001). Overall (U + C) operative mortality, expected mortality (E) and that for U and C cases are reported in Figure 1:
 

In all 8 years of experience the observed operative mortality rate was similar to the calculated expected risk and ranged from 0% to 38% according to the amount of C cases operated on each year. Multivariate logistic regression analysis revealed that older age and pericardial rupture significantly increased the risk of operative death, while male sex, preoperative complications, postoperative bleeding, and circulatory arrest and aortic cross-clamp time significantly predicted morbidity (p = 0.02).

Conclusions: Operative results of emergency repair of acute type A aortic dissection fluctuate in the recent years according to the number of complicated cases referred for operation. Earlier diagnosis and prompt referral before development of preoperative complications are essential to improve surgical results of these pts.