Usefulness of the Initial Noninvasive Imaging Study to Predict the Adverse Outcomes in the Medical Treatment of Acute Type A Aortic Intramural Hematoma

Background— There have been contradictory reports about the outcomes of medically treated patients with type A aortic intramural hematoma (AIH), and it is not certain if the initial noninvasive imaging studies can provide any useful predictors for the adverse outcomes. Methods and Results— Imaging studies and clinical outcomes of 25 consecutive patients with type A AIH who initially received medical treatment were analyzed retrospectively. Adverse outcomes (death, surgery, and development of dissection) occurred in 9 patients (group A), whereas the other 16 patients showed an uneventful course (group B). The hematoma thickness (14±4 versus 8±4 mm, P <0.005) and hematoma area (988±316 versus 555±352 mm 2 , P <0.01) in the imaging study performed ≤48 hours after onset of initial symptoms were significantly larger in group A; maximal aortic diameter (53±6 versus 48±8 mm, P =0.10) and aortic cross-sectional area (2247±501 versus 1809±626 mm 2 , P =0.09) were also somewhat larger in group A. The hematoma thickness was the only independent predictor for the adverse outcomes by stepwise multiple logistic regression analysis (odds ratio 1.41, 95% confidence interval 1.07 to 1.86, P <0.05). Hematoma thickness ≥11 mm predicted the adverse outcomes with sensitivity 89% and specificity 69%. No one with hemodynamically stable initial condition and the hematoma thickness <11 mm experienced the adverse outcomes. Conclusion— Noninvasive imaging study provides important prognostic information in the medical treatment of acute type A AIH, and initial hematoma thickness seems to be the best index for predicting adverse clinical outcome.