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

The aim of this study was to determine whether false lumen size predicts in-hospital complications for acute type B aortic dissection.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.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.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 mm2 vs. 1,899.3+/-1,642.4 mm2, 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>or=922 mm2 or BVI number>or=2 showed a significantly higher incidence of in-hospital complications than the other patients (p<0.001).A large MFLA and a higher BVI number are powerful predictors of in-hospital complications after acute type B aortic dissection.