According to Geu-Ru Hong (Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, Korea), edoxaban may be an alternative to warfarin for preventing thromboembolism in the first three months after surgical bioprosthetic valve replacement or repair. He explained that new data suggest the direct oral anticoagulant is non-inferior to warfarin in this context.
Speaking at the American College of Cardiology/World Congress of Cardiology’s virtual scientific sessions (ACC.20/WCC Virtual), Hong commented: “Early postoperative anticoagulation with warfarin is recommended in patients undergoing surgical bioprosthetic valve implantation or valve repair.” Furthermore, he explained to Cardiovascular News: “The current recommendation is for anticoagulation treatment for three months after valve replacement with a bioprosthetic valve/surgical valve repair. In Korea, all patients at low risk of bleeding are treated with anticoagulation treatment for three months to adhere to this recommendation.” However, at ACC.20/WCC Virtual, he noted whether direct oral anticoagulation could be an alternative to warfarin in this population was “unclear”.
Therefore, he said, the aim of the ENAVLE trial was to “compare the efficacy and safety of edoxaban with that of warfarin for three months in patients with who underwent surgical bioprosthetic valve implantation or valve repair”. Hong added that, in the trial, 220 patients who had undergone surgical valve replacement with a bioprosthetic valve or surgical valve repair were randomised to receive warfarin (110) or edoxaban (110). The primary efficacy outcome was the three-month composite rate of death, clinical thromboembolic events, and asymptomatic intracardiac thrombosis, and the primary safety outcome was the occurrence of major bleeding.
In terms of type of surgery patients had undergone, the most common type was aortic valve replacement, followed by mitral valve repair and mitral valve replacement. Additionally, 33% in the edoxaban group and 28% in the warfarin group underwent concomitant surgery (such as tricuspid annuloplasty).
In the intention-to-treat analysis, the primary efficacy outcome occurred in four patients in the warfarin group vs. no patients in the edoxaban group (p<0.001 for non-inferiority) while the primary safety outcome occurred in three patients in the edoxaban group and one patient in the warfarin group (p=0.013 for non-inferiority). Thus, overall, edoxaban was non-inferior to warfarin for preventing thromboembolism and the occurrence of major bleeding in the first three months after surgical bioprosthetic valve implantation or valve repair.
“Our findings suggest that edoxaban might be an alternative to warfarin in patients early after successful bioprosthetic valve implantation or valve repair,” Hong concluded.
According to Hong, edoxaban has some potential advantages over warfarin. “Anticoagulation therapy with warfarin has a narrow therapeutic window and requires frequent INR monitoring. Additionally, INR values are variable and often out of the therapeutic window—particularly during the early postoperative period, depending on the recovery of patient’s condition and changes in dietary intake. Edoxaban, as with other direct oral anticoagulants, has a lower risk of drug-drug interactions and drug-food interactions than has warfarin. Plus, routine monitoring of its anticoagulation effect is not required.”