Background. Many patients required secondary open arch operation due to new aortic pathologies or complications after thoracic endovascular aortic repair (TEVAR). In this study, we investigated the outcome of secondary open arch operation after prior TEVAR. Methods. Fifty-seven consecutive patients underwent secondary open arch operation after prior TEVAR. The major indications were retrograde type A aortic dissection (n = 24), proximal new aortic dissection (n = 8), and type Ia endoleak (n = 16). An elective operation was performed in 35 patients and an emergent operation in 22. The survival and freedom from aortic events during the follow-up were evaluated with the Kaplan-Meier survival curve and the log-rank test. The survival was also analyzed with the Cox analysis. Results. The in-hospital mortality was 7.0% (4 of 57). The mean follow-up time was 32.2 +/- 19.7 months. Five late deaths occurred. The overall survival at 1 year, 3 years, and 6 years was 89.5%, 84.6%, and 79.9%, respectively. Aortic events developed in 7 patients. Freedom from aortic events after the operation at 1 year, 3 years, and 6 years was 94.2%, 83.0%, and 77.8%, respectively. There were no differences in survival and freedom from aortic events between the elective group and the emergent group. The Cox analysis identified additional coronary artery bypass grafting and hypothermic circulatory arrest as independent factors predicting survival. Conclusions. Secondary open arch operation could be performed to treat the arch pathologies after TEVAR with acceptable early and midterm outcomes. (C) 2021 by The Society of Thoracic Surgeons