Long-Term Outcomes of Anticoagulation for Bioprosthetic Valve Thrombosis

Abstract

Background: Early in the prevention and treatment of bioprosthetic valve thrombosis (BPVT), anticoagulation is effective, but the long-term outcome after BPVT is unknown. Objectives: The goal of this study was to assess the long-term outcomes of patients with BPVT treated with anticoagulation. Methods: This analysis was a matched cohort study of patients treated with warfarin for suspected BPVT at the Mayo Clinic between 1999 and 2017. Results: A total of 83 patients treated with warfarin for suspected BPVT (age 57 ± 18 years; 45 men [54%]) were matched to 166 control subjects; matching was performed according to age, sex, year of implantation, and prosthesis type and position. Echocardiography normalized in 62 patients (75%) within 3 months (interquartile range [IQR]: 1.5 to 6 months) of anticoagulation; 21 patients (25%) did not respond to warfarin. Median follow-up after diagnosis was 34 months (IQR: 17 to 54 months). There was no difference in the primary composite endpoint between the patients with BPVT and the matched control subjects (log-rank test, p = 0.79), but the former did have a significantly higher rate of major bleeding (12% vs. 2%; p < 0.0001). BPVT recurred (re-BPVT) in 14 (23%) responders after a median of 23 months (IQR: 11 to 39 months); all but one re-BPVT patient responded to anticoagulant therapy. Patients with BPVT had a higher probability of valve re-replacement (68% vs. 24% at 10 years’ post-BPVT; log-rank test, p < 0.001). Conclusions: BPVT was associated with re-BPVT and early prosthetic degeneration in a significant number of patients. Indefinite warfarin anticoagulation should be considered after a confirmed BPVT episode, but this strategy must be balanced against an increased risk of bleeding.