Outcomes of Chimney Thoracic Endovascular Aortic Repair for an Aortic Arch Aneurysm.

Background: Chimney thoracic endovascular aneurysm repair (TEVAR) has advantages that include no requirements for special devices; however, problems have been identified such as gutter leaks. The aim of this study is to evaluate the short- and mid-term results of TEVAR with chimney technique including the safety, efficacy, and risk factors for occurrence of gutter endoleak in this technique.

Methods: A retrospective single-center study was conducted on 55 consecutive patients who underwent first-time chimney TEVAR for arch aneurysms in the past 7 years. This consisted of 33 cases of single-chimney (SC) TEVAR and 22 cases of double-chimney (DC) TEVAR. The outcomes of these 55 cases of SC-TEVAR and DC-TEVAR were retrospectively examined. Risk factors for endoleaks in chimney TEVAR were also examined.

Results: Operative mortalities of 3.0% and 4.5% were observed in SC-TEVAR and DC-TEVAR, respectively. Incidences of stroke were 12.1% in the SC-TEVAR and 4.5% in the DC-TEVAR, resulting in endoleaks in 16 patients (48.5%) in SC-TEVAR and 6 patients (27.3%) in DC-TEVAR. Only 1 of the 77 chimney grafts was occluded, with a patency rate of 98.7%. SC-TEVAR and small distance from the common carotid artery were the risk factors of type I endoleaks. Overall survival rates over a period of 1, 3, and 5 years were 82.3%, 78.0%, and 57.7%, respectively, in the SC-TEVAR group and 95.2%, 89.3%, and 76.5%, respectively, in the DC-TEVAR group. Freedom from aneurysm-related death over 1, 3, and 5 years was 82.3%, 69.0%, and 57.7%, respectively, in the SC-TEVAR group and 95.2%, 89.3%, and 89.3% in the DC-TEVAR group. Freedom from secondary intervention over 1, 3, and 5 years was 80.2%, 64.7%, and 47.2%, respectively, in the SC-TEVAR group and 95.0%, 74.0%, and 74.0%, respectively, in the DC-TEVAR group.

Conclusions: The short- and mid-term results of chimney TEVAR were worse than expectation. Especially, the results of SC-TEVAR were not acceptable because of extremely high incidence of type I endoleak and high incidence of stroke.