Early and late outcomes following aortic root enlargement: a multicenter propensity score-matched cohort analysis

Objective — The safety and efficacy of aortic root enlargement (ARE) at the time of aortic valve replacement (AVR) remains unknown. The objective of this multi-center study was to compare AVR with ARE to AVR for early and late mortality and secondary safety outcomes.

Methods — Clinical and administrative databases in Ontario, Canada, were linked to obtain patients undergoing AVR with or without ARE from 2008 to 2017. Baseline characteristics were compared and 1:1 propensity score matching was performed to account for differences in baseline characteristics. Early outcomes were compared in the matched groups. Late mortality was compared using Kaplan-Meier survival curves and a Cox-proportional hazard model.

Results — Sixteen thousand six hundred fifty-six patients undergoing AVR in 11 Ontario institutions were reviewed. Patients who underwent ARE were younger, nonurgent, more likely to be men and had lower rates of hypertension, ischemic heart disease, and congestive heart failure. Propensity score matching yielded similar groups for comparison, with 809 pairs for AVR versus AVR with ARE. There was no difference in 30-day mortality between AVR with ARE versus AVR (2.0% vs 2.1%; P = 1.00). Rates of chest reopening for bleeding, permanent pacemaker implantation, and blood transfusions were similar. Late mortality over 8 years was similar between AVR with ARE and AVR (P = .45). In a sensitivity analysis, results were similar in 525 pairs comparing AVR with coronary artery bypass grafting and ARE to AVR with coronary artery bypass grafting, except that chest reopening for bleeding was higher with AVR with coronary artery bypass grafting and ARE (7.2% vs 3.2%; P = .006).

Conclusions — The addition of ARE to isolated AVR can be safely performed to increase implanted prosthesis size without compromising early mortality. Additional studies with longer follow-up are necessary.