AbstractOBJECTIVESThis study aimed to reveal the association between lower-profile stent graft (LPSG) and embolism during thoracic endovascular aortic repair for non-dissecting distal arch and descending thoracic aortic aneurysm.METHODSThis study reviewed data of 35 patients who underwent thoracic endovascular aortic repair with LPSG (27 males; age: 77 ± 9.2 years) and 312 who underwent thoracic endovascular aortic repair with conventional-sized stent graft (CSSG) (247 males; age: 77 ± 7.4 years) from 2009 to 2021.RESULTSThe rate of total embolic events was significantly lower in the LPSG group (0/35 [0%]) than the CSSG group (34/312 [11.2%]) (P=0.035). Shaggy aorta (odds ratio: 5.220;P<0.001) were identified as positive embolic event predictors. The rate of total embolic events in 68 patients with shaggy aorta (12 in LPSG/56 in CSSG) was significantly lower in the LPSG group (0/12 [0%]) than the CSSG group (19/56 [34%]) (P=0.015). The rate of total embolic events in 279 patients with the non-shaggy aorta (23 in LPSG/256 in CSSG) reveals no difference between the 2 groups (0 [0%]/16 [6.3%]) (P=0.377).CONCLUSIONSLPSG usage could reduce embolism in thoracic endovascular aortic repair, and the difference was more pronounced in patients with the shaggy aorta. LPSG might be beneficial in preventing embolism in thoracic endovascular aortic repair for patients with a shaggy aorta.