Major bleeding complications and antithrombotic treatment after isolated surgical bioprosthetic aortic valve replacement

Abstract Background Despite advancements in surgical techniques and perioperative care, post-operative bleeds and stroke remain significant concerns after bioprosthetic surgical aortic valve replacement (SAVR). Purpose We assessed the incidence of short-term (30d) and long-term major bleeds and strokes and their relations to antithrombotic treatment after isolated bioprosthetic SAVR. Methods The CAREAVR study included 721 patients who underwent isolated SAVR at four Finnish university hospitals between 2002 and 2014. The day-to-day information on short-term antithrombotic treatment was available from a subgroup including 227 patients, of whom 138 (60.7%) had preoperative aspirin. Preoperative aspirin was usually discontinued the day before the index surgery. Enoxaparin 1mg/kg twice daily and vitamin K antagonist (VKA) were routinely initiated on the first postoperative day, and enoxaparin continued until the INR remained at a therapeutic level ≥ 2.0 for two days. The routine duration of VKA treatment after surgery was 3 months. Results The median follow-up time was 4.9 (interquartile range 3.0–7.0) years. During the short-term 30-day period, 31 (4.3%) patients had a major bleed, and 13 (1.8%) patients experienced a major stroke. A vast majority of the bleeding (80.6%) occurred within two days after the surgery, and the tail effect of preoperative aspirin (5-7d) was present in 51.6% of episodes, indicating unintentional triple antithrombotic therapy. During the long-term follow-up (>30d after the index surgery), 40 (5.5%) major bleeding episodes occurred, and 47 (6.5%) patients experienced a major stroke. Overall, 23 (57.5%) of the patients with major bleeding were on OAC during the event. In addition, 13 (27.7%) of the patients experiencing major stroke during the long-term follow-up were on OAC during the event. Conclusions Compared to major strokes, the incidence of perioperative major bleeds was over twofold, the majority occurring during the tail effect of preoperative aspirin. During the long-term follow-up, the risks of stroke and bleeding were equal, and the majority of bleeding episodes appeared during anticoagulation treatment.