LAUSR

In this recent study, Hartley and colleagues conducted a retrospective case series analysis of patients who underwent repair of acute type A dissection (ATAAD) at Royal Brompton and Harefield Trust, between January 2009 to December 2018. Patients who underwent total arch replacement or frozen elephant trunk were excluded. The remaining 116 patients compromised the cohort of this study and were divided into two groups, the ascending aorta interposition graft (AAG) and the nonvalve sparing aortic root replacement (ARR) group. No patients underwent valve‐sparing root replacement for ATAAD. Preoperative characteristics were comparable in both groups, except for diabetes and current smoking which were significantly higher in the ARR group. This difference was masked in the analysis by a comparable Euroscore II in both groups. Euroscore II has been shown to be of poor predictive value in aortic surgery and more so in ATAAD. In addition, the ARR group had more patients with connective tissue disease. The difference did not reach statistical significance (p = .289); however, it could not be totally dismissed in a small cohort. Hartley et al. presented that, in the absence of contraindications to a valve‐sparing operative technique, efforts to conserve the native aortic valve should be encouraged. This includes presentations with complicated aortic regurgitation. Their data illustrated a statistically significant improved mortality in the AAG cohort versus the ARR group. This was consistent both in the short term and in long‐term outcomes. In contrast, the incidence of postoperative complications such as renal failure, embolic stroke etc. was comparable between the cohorts. Furthermore, long‐term echocardiography follow‐up in the AAG cohort illustrated that the degree of aortic regurgitation and aortic valve dimensions at presentation, had no implications on long‐ term aortic valve competence. We congratulate the group on excellent short‐term mortality figures in the AAG group (1.6%). A meta‐analysis by Chen and colleagues concluded early mortality of 15.5% when utilizing the same surgical technique in 3295 patients. Furthermore, a recent study in 2017 by Valdis and colleagues yielded 30‐day mortality of 20.4%. The deviation against current literature by Hartley and colleagues potentially highlights an issue with smaller sample size, being more prone to statistical variability. The concept of statistical variability continued into mortality statistics. Early 30‐day mortality statistics, analysed by the multivariate logistic regression analysis, presented an odds ratio of 35.2, with respect to ARR. However, the 95% confidence interval presented a huge variation between 2.38 and 522.0. Similarly, the overall survival comparison between the two cohorts suffered from broad confidence intervals. Formulating a concrete conclusion based upon such wide confidence intervals is difficult. Furthermore, the mode of death, either cardiovascular/ valve related or not, was not addressed. A possible confounding variable in Hartley and colleagues' study, favouring AAG, is surgeon preference. Hartley et al. acknowledged that surgeons prefer the root replacement technique in patients who present with more extensive disease. Extensive disease at presentation, illustrated through a larger aortic root and weaker aortic tissue viability, was not reflected in the operative risk assessment. This can propagate inflated mortality in the ARR cohort. The long‐term freedom from significant regurgitation across the native aortic valve was addressed by Hartley and colleagues. The