See Article page XXX. Commentary: Redo of aortic root surgery: Tackling the nightmare successfully Andrea Biondi, MD, a and Mauro Lo Rito, MD b Brown and colleagues 1 investigate the outcome of reopera- tive aortic root replacement (ARR) in patients having un- dergone previous cardiac operations. They included all patients who underwent ARR (ie, aortic valve and aortic root) and divided them into the first sternotomy and redo sternotomy. Within the redo sternotomy population, they performed a subgroup analysis to look at the difference be- tween the ARR in patients who were resternotomy for any other surgery and ARR redo of previous aortic root surgery. They found that redo ARR can be safely done with similar results to first-time ARR and previous sternotomy. In partic- ular, mortality for such surgery reported by Brown and col- leagues 1 is comparable to other studies, especially for the first-time ARR. 2,3 The authors have to be congratulated for those brilliant results in such complex reoperative sur- gery. However, looking at the details of the numbers, some questions rise and remain unanswered. Among the significant findings of this study is that there is no difference in survival among redo ARR to redo-sternotomy to first ARR, with 12% mortality in both groups after propensity matching. This is a favorable result, but the lack of differ- ences among the 2 matched groups is not due to the low redo ARR mortality, which is a remarkable achievement, but to the slightly higher mortality in redo first ARR than in other reports. 2,3 We could not tease out the reasons for such incremental mortality after matching. Conceptually, despite being a resternotomy, a first-time ARR should not have such a mortality rate considering that the aortic root was not previously replaced. A possible explanation may be the increment of endocarditis indication before and after matching. In particular, the percentage of infective endocar- ditis in the redo sternotomy first ARR rose from 39.7% before matching to 51.5% after matching and this is a well-known risk factor for mortality. 2 Brown and collegues’ 1 results are excellent for such com- plex operations; it remains unexplained why they experi- enced such increased mortality. The take-home message is not to be afraid of such nightmare cases and perform redo ARR. Although we have to be aware of hidden risks and remember that center experience and surgeon ability are fundamental for a successful treatment. References 1. Brown JA, Serna-Gallegos D, Kilic A, Longo S, Chu D, Navid F, et al. Outcomes of aortic root replacement after previous aortic root surgery. J Thorac Cardiovasc Surg. 2022. XXX:XXX. 2. Jassar AS, Desai ND, Kobrin D, Pochettino A, Vallabhajosyula P, Milewski RK, et al. Outcomes of aortic root replacement after previous aortic root replacement: the “true” redo root. Ann Thorac Surg. 2015;99:1601-9. 3. Varrica A, Satriano A, de Vincentiis C, Biondi A, Trimarchi S, Ranucci M, et al. Bentall operation in 375 patients: long-term results and predictors of death. J Heart Valve Dis. 2014;23:127-34. From the Departments of a Cardiac Surgery and b Congenital Cardiac Surgery, IRCCS Policlinico San Donato, San Donato Milanese, Milano, Italy. Disclosures: The authors reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest. Received for publication Oct 15, 2021; revisions received Oct 15, 2021; accepted for publication Oct 18, 2021. Address for reprints: Mauro Lo Rito, MD, Department of Congenital Cardiac Sur- gery, IRCCS Policlinico San Donato, Piazza Edmondo Malan 2, 20097 San Donato Milanese, Italy (E-mail: mauro.lorito@gmail.com). J Thorac Cardiovasc Surg 2021;-:1 0022-5223/$36.00 Copyright Ó 2021 by The American Association for Thoracic Surgery https://doi.org/10.1016/j.jtcvs.2021.10.024 Andrea Biondi, MD, and Mauro Lo Rito, MD CENTRAL MESSAGE Performing aortic root replace- ment in patients with prior operation is a demanding sur- gery. But results are reassuring, and we should not be scared to replace a previously operated-on aortic root. The Journal of Thoracic and Cardiovascular Surgery c Volume -, Number - 1 Biondi and Lo Rito Commentary