Differential impact of intimal tear location on aortic dilation and reintervention in acute type I aortic dissection after total arch replacement

Objective: The study objective was to evaluate the differential impact of intimal tear location on aortic dilation and reintervention after total arch replacement for acute type I aortic dissection. Methods: From 2009 to 2016, 85 patients underwent total arch replacement for acute type I aortic dissection with residual dissected thoracoabdominal aorta. Forty patients (47%) underwent serial computed tomography scans that were sufficient for analysis. Among these, 14 (35%) underwent total arch replacement via the frozen elephant trunk procedure. Intimal tears were analyzed (size and number) at 3 different levels (level 1, proximal descending thoracic aorta; level 2, distal descending thoracic aorta; level 3, abdominal aorta). Aortic diameter was measured at 4 levels (pulmonary artery bifurcation, celiac axis, maximal abdominal aorta, and maximal thoracoabdominal aorta) using serial follow-up computed tomography scans. The linear mixed model for a repeated-measures random intercept and slope model was used. The rate of freedom from reintervention was analyzed. Results: In the unadjusted analysis, initial diameter of pulmonary artery bifurcation level, number of intimal tears, presence of 3- or 5-mm intimal tears, and frozen elephant trunk were not significant factors for aortic dilation or shrinking. The significant factors for aortic dilation were intimal tear location and number of visceral branches from the false lumen. The 3-year freedom from reintervention rate was significantly higher in patients with intimal tears 3 mm or greater at level 3 than in those with tears at level 1 (94.1% vs 37.5%, log-rank, P<.001). Conclusions: Intimal tear in the proximal descending thoracic aorta is the most important factor for aortic dilation and reintervention in acute type I aortic dissection after total arch replacement.