Risk stratification in acute type A dissection: proposition for a new scoring system

Background. The aim of this study was to develop a scoring system for operative mortality of patients with acute type A aortic dissection. Methods. Between 1974 and 1999, a total of 252 patients were operated on for an acute type A aortic dissection. We reviewed retrospectively preoperative and intraoperative records to conduct an analysis of risk factors associated with surgery. Multivariate analysis was used to predict operative mortality and to provide a preoperative risk profile of each individual patient that could be used for future patients. Results. Operative mortality was 25.0% (n = 63). A logistic regression model with three explanatory variables to predict operative death showed a good fit: the risk factors associated with operative mortality were preoperative cardiopulmonary resuscitation (p = 0.0013, odds ratio = 15.7) and iatrogenic dissection (p = 0.0014, odds ratio = 9.8). Drained pericardial tamponade (p = 0.0386, odds ratio = 0.12) appeared to be a protective factor associated with decreased mortality. Conclusions. Because existing scoring systems do not fit this pathologic condition, we propose the use of this Antonius Dissection Scoring System, based on the logistic regression model, to predict the chances of operative mortality for each patient before operation. The survival of patients with concomittant pericardial tamponade may benefit from pericardial drainage.