Improved long-term outcome of surgical AVR for AS: Results from a population-based cohort

Background: The aim of this retrospective study was to determine changes in outcomes after surgical aortic valve replacement (SAVR) for aortic stenosis (AS) in Iceland over a 15-year period. Methods: We included 587 patients who underwent SAVR for AS in Iceland during the period 2002-2016, with a total follow-up of 3245 patient-years. Short-term and long-term outcomes, 30-day mortality, and long-term survival (Kaplan–Meier) were analyzed. Univariate linear regression and univariate and multinomial logistic regression analyses were performed on preoperative and perioperative variables. Poisson regression analysis was used to evaluate changes in rates of short-term outcomes. Results: Mean age was 71 years, 65.1% were males, and mean EuroSCORE II was 3.9. Mean preoperative aortic valve area increased significantly (0.013 cm²/year; P <.001) and mean aortic cross-clamp time declined (108 minutes, 2.8 min/year; P <.001). The rate of complications decreased, including new-onset atrial fibrillation (60.9% overall, decreased by 3.1%/year, P =.02), acute kidney injury (17.1%, 7.6%/year, P <.001), and reoperation for bleeding (12.5%, 6.3%/year, P =.02). Operative mortality did not change (5.4%); nor did 1- and 5-year overall survival (92.5% and 81.6%, respectively). Notable long-term events were chronic heart failure (27.7 admissions/100 patient-years), embolic event (15.9/100 patient-years), and bleeding (13.0/100 patient-years). Conclusions: Results of SAVR in this well-defined nationwide cohort of patients in Iceland have improved. This may be related to the patients having less severe AS at the time of operation and shorter operating times, as reflected by lower rates of short-term complications. However, the rate of long-term complications did not change significantly, with prosthetic valve-specific events being rare.