Preoperative thoracic false lumen branches are predictors of aortic enlargement after stent grafting for DeBakey IIIb aortic dissection

Objective: The study objective was to assess the effect of preoperative thoracic false lumen branches on thoracic aortic enlargement along the stent graft after thoracic endovascular aortic repair for DeBakey IIIb aortic dissection. Methods: From January 2011 to December 2013, 67 patients who underwent thoracic endovascular aortic repair for DeBakey IIIb aortic dissection were retrospectively investigated. We assessed preoperative thoracic false lumen branches and diameter measurements at the level of the tracheal carina. Patients with a median follow-up of 12.2 months (interquartile range, 4.3-26.6 months) were categorized into 2 groups based on a receiver operating characteristic curve analysis: group A (preoperative thoracic false lumen branches >= 8, n = 28) and group B (preoperative thoracic false lumen branches < 8, n = 39). Diameter changes over time were evaluated using a mixed model approach. A multivariate Cox regression analysis was used to study the influence of the preoperative thoracic false lumen branches on thoracic aortic enlargement along the stent graft. Results: Six patients experienced thoracic aortic enlargement along the stent graft during follow-up (6 in group A, 0 in group B). The cumulative thoracic aortic enlargement along the stent-graft rate was higher in group A than in group B (log-rank P <. 01). Diameter data showed significantly more reduction of the thoracic false lumen from preprocedure to 12 months in group B than in group A (change difference, 2.51; standard error, 0.99; P=.01). Complete false lumen thrombosis was more prominent in group B than in group A at each follow-up time point. After multivariate adjustment, preoperative thoracic false lumen branches were associated with thoracic aortic enlargement along the stent graft (hazard ratio, 2.92; 95% confidence interval, 1.06-8.01). Conclusions: Preoperative thoracic false lumen branches are amorphologic predictor of thoracic aortic enlargement along the stent graft in DeBakey IIIb aortic dissection after thoracic endovascular aortic repair.