The role of false lumen size in prediction of in-hospital complications after acute type B aortic dissection

Objectives The aim of this study was to determine whether false lumen size predicts in-hospital complications for acute type B aortic dissection. Background The incidence of complications developing in patients with acute type B aortic dissection has been high. However, methods for recognizing high-risk patients have not been well-studied. We used quantitative analysis by computed tomography (CT) to predict the occurrence of in-hospital complications. Methods Fifty-five consecutive patients with acute type B aortic dissection documented by CT imaging were analyzed. They were divided into groups, with and without in-hospital complications, and compared regarding maximal aortic diameter (MAD), maximal false lumen area (MFLA), minimal true lumen area (MTLA), branch-vessel involvement (BVI), and longitudinal length (LL) of aortic dissection. Results There were 31 patients with a stable course (group 1) and 24 patients who developed complications (group 2). The MFLA of group 2 was significantly larger than that of group 1 (group 1 vs. group 2 = 577.7 +/- 273.2 mm(2) vs. 1,899.3 +/- 1,642.4 mm(2), p < 0.001). The BVI number was also higher in group 2 (group 1 vs. group 2 = 1.0 +/- 1.1 vs. 3.3 +/- 2.0, p < 0.001). On multivariate analysis, only MFLA and BVI number were independent predictors of in-hospital complications. Patients with initial MFLA >= 922 mm(2) or BVI number >= 2 showed a significantly higher incidence of in-hospital complications than the other patients (p < 0.001). Conclusions A large MFLA and a higher BVI number are powerful predictors of in-hospital complications after acute type B aortic dissection.