Elephant Trunk Technique versus J Graft Open Stent Graft at Distal Anastomosis of Total Arch Replacement

Objectives: While elephant trunk has been an established technique for distal anastomosis in total arch replacement, frozen elephant trunk with various open stent grafts (OSGs) has been shown effective for the patients with aneurysms and dissections at arch and proximal descending aorta. J graft open stent graft is one of OSGs manufactured in Japan and is widely used from 2014. The stent is composed with unique oval shaped nitinol and is thought to comfort to the curvature of the aorta. The aim of this study is to evaluate outcomes of total arch replacement with J graft open stent graft comparing to those with conventional elephant trunk technique.

Methods: A total of 161 consecutive total arch replacements were performed from April 2013 to December 2017. Among those, 67 patients were operated with conventional elephant trunk (Group ET) and 67 patients were operated with J graft open stent graft (Group J). Indications for open stent graft are: Extensive TAA involving descending Aorta, Collapsed true lumen or distally located entry in aortic dissection, Use as a landing zone for scheduled staged TEVAR, etc. Operative courses and midterm outcomes of Group ET and Group J are retrospectively examined and compared.

Results: Mean age of group ET and group J is 65.6 ± 10.7 vs. 64.9 ± 13.6 (p = 0.751), 82.1 vs 76.1 (p = 0.395) are males (%), and ratio of aortic dissection (%) in each group is 49.3 versus 65.7 (p = 0.055). There was no significant difference between group ET and group J in mean operation time (min) (399.0 ± 97.6 vs. 411.7 ± 88.1, p = 0.429), mean clamp time (min) (126.7 ± 30.6 vs. 124.6 ± 36.6, p = 0.721), mean bypass time (min) (248.9 ± 45.4 vs. 256.5 ± 60.0, p = 0.408), but mean circulatory arrest time (min) in group J was shorter than that in group ET (ET: 61.5 ± 14.6 vs. J: 53.7 ± 11.8, p = 0.001). There was no paraplegia and 1 sine in group J. Kaplan–Meier analysis showed no significant difference between groups in survival (ET: 95.7% vs. J: 92.0%, p = 0.123) and aortic event-free survival (ET: 81.6 vs. J: 80.7%, p = 0.156) in 3 years. Mean proximal descending aortic diameter (mm) was reversely changed in group J (32.4 ± 6.3 → 31.0 ± 5.0, p = 0.015), especially in acute dissection (32.4 ± 3.5 → 30.6 ± 3.8, p = 0.002).

Conclusions: Midterm outcomes were not different between two groups, but circulatory arrest time was shorter in group J, perhaps because using J open stent graft could facilitate distal anastomosis. And inserted stent graft related to better remodeling of proximal descending aorta without few adverse events.