Surgical Enlargement of the Aortic Root Does Not Increase the Operative Risk of Aortic Valve Replacement

Background: Surgical aortic root enlargement (ARE) during aortic valve replacement (AVR) allows for larger prosthesis implantation and may be an important adjunct to surgical AVR in the transcatheter valve-in-valve era. The incremental operative risk of adding ARE to AVR has not been established. We aimed to evaluate the early outcomes of patients undergoing AVR with or without ARE. Methods: From January 1990 to August 2014, 7039 patients underwent AVR (AVR+ARE, n=1854; AVR, n=5185) at a single institution. Patients with aortic dissection and active endocarditis were excluded. Mean age was 65±14 years and 63% were male. Logistic regression and propensity score matching were used to adjust for unbalanced variables in group comparisons. Results: Patients undergoing AVR+ARE were more likely to be female (46% versus 34%, P<0.001) and had higher rates of previous cardiac surgery (18% versus 12%, P<0.001), chronic obstructive pulmonary disease (5% versus 3%, P=0.004), urgent/emergent status (6% versus 4%, P=0.01), and worse New York Heart Association status (P<0.001). Most patients received bioprosthetic valves (AVR+ARE: 73.4% versus AVR: 73.3%, P=0.98) and also underwent concomitant cardiac procedures (AVR+ARE: 68% versus AVR: 67%, P=0.31). Mean prosthesis size implanted was slightly smaller in patients requiring AVR+ARE versus AVR (23.4±2.1 versus 24.1±2.3, P<0.001). In-hospital mortality was higher after AVR+ARE (4.3% versus 3.0%, P=0.008), although when the cohort was restricted to patients undergoing isolated aortic valve replacement with or without root enlargement, mortality was not statistically different (AVR+ARE: 1.7% versus AVR: 1.1%, P=0.29). After adjustment for baseline characteristics, AVR+ARE was not associated with an increased risk of in-hospital mortality when compared with AVR (odds ratio, 1.03; 95% confidence interval, 0.75-1.41; P=0.85). Furthermore, AVR+ARE was not associated with an increased risk of postoperative adverse events. Results were similar if propensity matching was used instead of multivariable adjustments for baseline characteristics. Conclusions: In the largest analysis to date, ARE was not associated with increased risk of mortality or adverse events. Surgical ARE is a safe adjunct to AVR in the modern era.