BACKGROUND The optimal brain protection strategy for prolonged periods of circulatory arrest is still controversial. This study evaluated whether retrograde cerebral perfusion (RCP) provides adequate brain protection for prolonged periods of deep hypothermic circulatory arrest (DHCA). METHODS From January 1997 to December 2014, 1,043 patients underwent aortic arch operations using RCP and DHCA at 18°C. The DHCA time for 993 patients was 49 minutes or less and the DHCA time for the remaining 50 patients was 50 minutes or more. Propensity matching between the two groups was performed, taking into account the main preoperative and surgical variables and all the preoperative and intraoperative neurologic risk factors. Logistic regression analysis was performed to identify independent predictors of operative death and postoperative cerebral complications. RESULTS In the unmatched population, mortality in the 50 minutes or more vs the 49 minutes or less group was 8% vs 3.8% (p = 0.143), and the stroke rate was 2% vs 1.2% (p = 0.623). Propensity matching resulted in 48 pairs. Operative death and incidence of transient and permanent neurologic deficit were similar and not statistically significant in the matched groups for all comparisons. No difference in the incidence of other major postoperative complications was found between the two groups. Midterm survival was similar. Regression analysis showed DHCA duration was not independently associated with operative death or postoperative neurologic deficits. CONCLUSIONS RCP is an effective adjunctive cerebral protection strategy for complex aortic arch aneurysm repair with prolonged DHCA and is not associated with increased death or neurologic complications.