Yutaka Okita

OBJECTIVES The goal of this study was to evaluate the fate of the downstream aorta following total arch replacement. METHODS Between October 1999 and March 2018, a total of 740 patients underwent total arch replacement. After excluding connective tissue disease, previous descending or thoracoabdominal aortic surgery, patients without adequate preoperative images or operative mortality, late outcomes consisting of additional surgery for distal dilation and distal aortic events were evaluated in 623 survivors (240 aortic dissections, including 139 patients with acute dissection and 383 with a non-dissection aneurysm). The mean follow-up was 5.0 ± 4.0 years. RESULTS The mean preoperative maximum diameter of the descending aorta was 36.9 ± 8.0 mm. An elephant trunk was inserted in 232 patients, including 183 patients with aortic dissection. Freedom from additional surgery for distal dilation was 88.5% at 5 years and 80.2% at 10 years. Freedom from distal aortic events was 81.9% at 5 years and 70.5% at 10 years. Multivariable regression analysis demonstrated that the preoperative diameter of the descending aorta was a significant risk factor for unfavourable distal aortic events. Computed tomography evaluation demonstrated a significant increase in the descending aortic diameter over time (P < 0.001). Positive aortic remodelling was observed in the proximal descending (P < 0.001) to mid-descending (P < 0.001) aorta exclusively in patients with acute aortic dissection. CONCLUSIONS The diameter of the descending aorta increased significantly after total arch replacement, particularly in the distal descending aorta. The preoperative descending aortic diameter portended a significant risk for unfavourable distal aortic events.