Comparison of Direct Oral Anticoagulants Versus Warfarin in Patients With Atrial Fibrillation and Bioprosthetic Heart Valves

Direct oral anticoagulants for atrial fibrillation in early postoperative valve repair or bioprosthetic replacement

OBJECTIVE

Despite increased use of direct oral anticoagulants (DOACs), limited evidence guides their use in the early postoperative period after bioprosthetic valve implantation in patients with atrial fibrillation. Our objective was to describe the efficacy and safety of DOACs and warfarin in the first 3 months after surgical bioprosthetic valve replacement or repair in patients with atrial fibrillation.

METHODS

This was a retrospective, registry-informed cohort study of surgical patients who underwent bioprosthetic valve replacement or repair, had concomitant atrial fibrillation and received oral anticoagulation at discharge. The primary efficacy outcome was a composite of death, ischemic stroke, transient ischemic attack, and systemic embolism; the primary safety outcome was a composite of major bleeding. Key secondary outcomes were comparative analyses of primary outcomes, temporal anticoagulation prescribing patterns, and 30-day readmission rates.

RESULTS

A total of 1743 patients were included. Of the 570 patients in the DOAC group, 17 (2%) met the composite efficacy outcome and 55 (10%) met the composite safety outcome. Of the 1173 patients receiving warfarin, 41 (3%) and 114 (10%) met the composite efficacy and safety outcomes, respectively. Comparative secondary analysis was not statistically significant for either the efficacy (adjusted odds ratio, 0.85; 95% confidence interval, 0.46-1.55, P = .59) or safety (adjusted odds ratio, 0.94; 95% confidence interval, 0.66-1.34, P = .76) outcomes. The 30-day readmission rates were similar between both groups.

CONCLUSIONS

Our results suggest DOACs may be safe and effective alternatives to warfarin in the early postoperative period after valve repair or surgical bioprosthetic replacement. Confirmation awaits adequately powered prospective studies.

Non-Vitamin K Antagonist Versus Vitamin K Antagonist Oral Anticoagulant Agents After Transcatheter Aortic Valve Replacement

BACKGROUND

Studies comparing long-term outcomes between non-vitamin K antagonist (VKA) oral anticoagulant agents (direct oral anticoagulant agents [DOACs]) and VKA anticoagulant agents after transcatheter aortic valve replacement (TAVR) are scarce, with conflicting results.

OBJECTIVES

The aim of this study was to examine the periprocedural, short-term, and long-term safety and effectiveness of DOACs vs VKAs in patients undergoing TAVR via femoral access with concomitant indications for oral anticoagulation.

METHODS

Consecutive patients undergoing transfemoral TAVR in the prospective national SwissTAVI Registry between February 2011 and June 2021 were analyzed. Net clinical benefit (a composite of all-cause mortality, myocardial infarction, stroke, and life-threatening or major bleeding) and the primary safety endpoint (a composite of life-threatening and major bleeding) were compared between the VKA and DOAC groups at 30 days, 1 year, and 5 years after TAVR.

RESULTS

After 1:1 propensity score matching, 1,454 patients were available for analysis in each group. There was no significant difference in the rate of the net clinical benefit and the safety endpoints between the groups as assessed at 30 days and 1 and 5 years post-TAVR between VKAs and DOACs. VKAs were associated with significantly higher rates of 1- year (HR: 1.28; 95% CI: 1.01-1.62) and 5-year (HR: 1.25; 95% CI: 1.11-1.40) all-cause mortality. Long-term risk for disabling stroke was significantly lower in the VKA group after excluding periprocedural events (HR: 0.64; 95% CI: 0.46-0.90).

CONCLUSIONS

At 5 years after TAVR, VKAs are associated with a higher risk for all-cause mortality, a lower risk for disabling stroke, and a similar rate of life-threatening or major bleeding compared with DOACs. (SwissTAVI Registry; NCT01368250).

An Evidence-Based Approach to Anticoagulation Therapy Comparing Direct Oral Anticoagulants and Vitamin K Antagonists in Patients With Atrial Fibrillation and Bioprosthetic Valves: A Systematic Review, Meta-Analysis, and Network Meta-Analysis

Direct oral anticoagulants (DOACs) are a newer class of anticoagulants that inhibit factor Xa or factor IIa and include drugs such as rivaroxaban, apixaban, edoxaban, betrixaban, and dabigatran. Although vitamin K antagonists (VKAs) have been traditionally used to prevent thromboembolic events, DOACs have gained popularity because of their faster onset and offset of action and reduced need for monitoring. This study aimed to provide more data for anticoagulants in patients with atrial fibrillation with bioprosthetic heart valves by incorporating all available trials to date. A search was performed across 5 electronic databases to identify relevant studies. We analyzed the data using a pooled risk ratio for categorical outcomes and used the I2 test to determine heterogeneity. The quality of randomized controlled trials was assessed using the Cochrane risk of bias assessment tool, and the National Institutes of Health tool was used for observational studies. Our study included a frequentist network meta-analysis (MA) of the aggregate data to obtain the network estimates for the outcomes of interest. We retrieved 28 studies with a total of 74,660 patients with bioprosthetic heart valves. Our MA significantly showed that DOACs decrease the risk of all-cause bleeding (risk ratio [RR] 0.80, 95% confidence interval [CI] 0.75 to 0.85, p >0.00001), stroke and systemic embolization (RR 0.89, 95% CI 0.80 to 0.99, p = 0.03), and intracranial bleeding outcomes (RR 0.62, 95% CI 0.45 to 0.86, p = 0.004) compared with VKA. In contrast, there was no significant difference between the compared groups in major bleeding (RR = 0.92, 95% CI 0.84 to 1.02, p = 0.10) and all-cause mortality outcomes (RR = 0.96, 95% CI 0.85 to 1.07, p = 0.43), respectively. In addition, the network MA results did not favor any of the studied interventions over each other (p <0.05) regarding all-cause bleeding, mortality, stroke and systemic embolization, and major bleeding outcomes. In conclusion, our study found that DOACs are more effective in reducing the risk of bleeding, stroke, systemic embolism, and intracranial bleeding than VKAs. However, no significant difference was observed in the incidence of gastrointestinal bleeding, major bleeding, thromboembolic events, and all-cause mortality. In addition, our network MA did not identify any specific DOAC treatment as more favorable than others.

DOAC versus VKA in patients with atrial fibrillation and bioprosthetic valves: a systematic review and meta-analysis

INTRODUCTION AND OBJECTIVES

Direct oral anticoagulant (DOAC) therapy has been shown to be safe and effective in patients with atrial fibrillation (AF). However, outcomes in AF patients with bioprosthetic valves are unclear, as this population has been underrepresented in clinical trials. The aim of this study was to assess the safety and efficacy of DOACs in this population based on the existing published literature.

METHODS

A systematic search and review were conducted to identify randomized clinical trials and comparative observational studies published from 2017 to January 2022 that compared DOACs and vitamin K antagonists (VKAs) in AF patients with bioprosthetic valves. Hazard ratios (HR) were collected to compare the 2 treatments in terms of cardiovascular and all-cause mortality, stroke/systemic embolism, and major bleeding. A meta-analysis combining the results was performed.

RESULTS

We included 12 studies (30 283 patients). DOACs and VKAs were compared based on HRs at the 95% confidence interval. DOAC therapy was associated with a significant 9% reduction in all-cause mortality (HR, 0.91; 95%CI, 0.85-0.97; P=.0068; I2=8%), with no significant differences in the risk of stroke/systemic embolism (HR, 0.87; 95%CI, 0.67-1.14; P=.29; I2=45%) or major bleeding (HR, 0.82; 95%CI, 0.67-1.00; P=.054; I2=48.7%).

CONCLUSIONS

DOAC therapy in AF patients with bioprosthetic valves may be associated with a significant reduction in all-cause mortality, with no reduction in the efficacy of stroke/systemic embolism prevention or increase in major bleeding risk.

Direct oral anticoagulants in patients with a left-sided bioprosthetic heart valve: a systematic review and meta-analysis

To compare the efficacy/effectiveness and safety of DOACs versus VKAs in patients with a previously and newly surgically implanted BHV with or without AF. A systematic search on MEDLINE and EMBASE was performed till November 2022. Treatment effects were estimated with relative risk (RR) and 95% confidence intervals (CIs). Statistical heterogeneity was assessed with the I2 statistic. Four randomized controlled trials (RCTs), 2 subgroup analysis from ARISTOTLE and ENGAGE-AF-TIMI 48 and 4 observational studies were included for a total of 5808 patients, 1893 on DOACs and 3915 on VKAs. AF prevalence was 98.28%. In the overall analysis, DOACs vs VKAs were associated with a RR for stroke/transient ischemic attack (TIA)/systemic embolism (SE) of 0.63 (95% CI 0.51-0.79; I2 = 0%) and a RR of major bleeding of 0.50 (95% CI 0.39-0.63; I2 = 0%) in a median follow-up of 19 months (IQR 4.5-33.4). In the 3 RCTs (DAWA, RIVER, ENAVLE), DOACs vs VKAs were associated with a RR of stroke/TIA/SE and major bleeding of 0.38 (95% CI 0.13-1.58, I2 = 0%) and of 0.68 (95% CI 0.32-1.44; I2 = 5%) respectively. In patients randomized during the first three months from valve surgery, DOACs vs VKAs were associated with a RR of stroke/TIA/SE and major bleeding of 0.54 (95% CI 0.14-2.08; I2 = 0%) and of 0.76 (95% CI 0.05-10.72; I2 = 66%). In previously implanted BHV patients with AF, DOACs showed a risk-benefit profile at least comparable to VKAs. DOACs showed a similar, even if underpowered, risk-benefit profile during the first three months after BHV implantation prevalently in patients with AF.

Direct Oral Anticoagulants for Stroke Prevention in Special Populations: Beyond the Clinical Trials

Currently, direct oral anticoagulants (DOACs) are the first-line anticoagulant strategy in patients with non-valvular atrial fibrillation (NVAF). They are characterized by a more favorable pharmacological profile than warfarin, having demonstrated equal efficacy in stroke prevention and greater safety in terms of intracranial bleeding. The study population in the randomized trials of DOACs was highly selected, so the results of these trials cannot be extended to specific populations such as obese, elderly, frail, and cancer patients, which, on the other hand, are sub-populations widely represented in clinical practice. Furthermore, due to the negative results of DOAC administration in patients with mechanical heart valves, the available evidence in subjects with biological heart valves is still few and often controversial. We sought to review the available literature on the efficacy and safety of DOACs in elderly, obese, underweight, frail, cancer patients, and in patients with bioprosthetic heart valves with NVAF to clarify the best anticoagulant strategy in these special and poorly studied subpopulations.

Direct Oral Anticoagulants Versus Warfarin in Patients With Atrial Fibrillation and Valve Replacement or Repair

Background

We sought to examine outcomes of direct oral anticoagulants (DOACs) versus warfarin in atrial fibrillation with valve repair/replacement.

Methods and Results

Two atrial fibrillation cohorts from Medicare were identified from 2015 to 2019. They comprised patients who underwent surgical or transcatheter mitral valve repair (MV repair cohort) and surgical aortic or mitral bioprosthetic or transcatheter aortic valve replacement (bioprosthetic cohort). Each cohort was divided into warfarin and DOACs (apixaban, rivaroxaban, and dabigatran) groups. Study outcomes included mortality, stroke, and major bleeding. Inverse probability weighting was used for adjustment between the 2 groups in each cohort. The MV repair cohort included 1178 patients. After a median of 468 days, DOACs were associated with lower risk of mortality (hazard ratio [HR], 0.67 [95% CI, 0.55–0.82], P<0.001), ischemic stroke (HR, 0.72 [95% CI, 0.52–1.00], P=0.05) and bleeding (HR, 0.79 [95% CI, 0.63–0.99], P=0.04) compared with warfarin. The bioprosthetic cohort included 8089 patients. After a median follow‐up of 413 days, DOACs were associated with similar risk of mortality (adjusted HR, 0.93 [95% CI, 0.86–1.01], P=0.08), higher risk of ischemic stroke (adjusted HR, 1.27 [95% CI, 1.13–1.43], P<0.001), and lower risk of bleeding (adjusted HR, 0.86 [95% CI, 0.80–0.93], P<0.001) compared with warfarin.

Conclusions

In patients with atrial fibrillation, DOACs are associated with similar mortality, lower bleeding, but higher stroke with bioprosthetic valve replacement and lower risk of all 3 outcomes with MV repair compared with warfarin.

An Updated Meta-Analysis of DOACs vs. VKAs in Atrial Fibrillation Patients With Bioprosthetic Heart Valve

Background

Current guidelines recommend the utilization of direct-acting oral anticoagulants (DOACs) in patients with non-valvular atrial fibrillation (AF). However, the optimal anticoagulation strategy for AF patients with bioprosthetic heart valves (BPHV) remains controversial. Therefore, we conducted this meta-analysis to explore the effect of DOACs versus vitamin K antagonists (VKAs) in this population.

Methods

We systematically searched the PubMed and Embase databases until November 2021 for studies reporting the effect of DOACs versus VKAs in AF patients with BPHV. Adjusted risk ratios (RRs) and 95% confidence intervals (CIs) were pooled using the random-effects model with an inverse variance method.

Results

We selected four randomized clinical trials and seven observational studies (2236 DOAC- and 6403 VKAs-users). Regarding the effectiveness outcomes, there were no significant differences between DOACs and VKAs in stroke or systemic embolism (RR = 0.74, 95%CI: 0.50–1.08), ischemic stroke (RR = 1.08, 95%CI: 0.76–1.55), all-cause death (RR = 0.98, 95%CI: 0.86–1.12), and cardiovascular death (RR = 0.85, 95%CI: 0.40–1.80). In terms of the safety outcomes, DOACs was associated with lower risks of major bleeding (RR = 0.70, 95%CI: 0.59–0.82) and intracranial bleeding (RR = 0.42, 95%CI: 0.26–0.70), but the risks of any bleeding (RR = 0.85, 95%CI: 0.65–1.13) and gastrointestinal bleeding (RR = 0.92, 95%CI: 0.73–1.17) are not significantly different when compared with VKAs. The subgroup analysis with follow-up as a covariate revealed that the DOACs had lower risks of SSE (RR = 0.59, 95%CI: 0.37–0.94) and major bleeding (RR = 0.69, 95%CI: 0.58–0.81) in patients with a mean follow-up of more than 24 months, but no statistical differences were found in patients with the follow-up less than 24 months (SSE: RR = 1.10, 95%CI: 0.92–1.32; major bleeding: RR = 0.91, 95%CI: 0.42–2.01).

Conclusions

In AF with BPHV, patients on DOACs experienced a reduced risk of major bleeding and intracranial bleeding compared with VKAs, while the risks of stroke, cardiovascular death, and all-cause mortality were similar.

Direct oral anticoagulation in atrial fibrillation and heart valve surgery-a meta-analysis and systematic review

AIMS

Oral anticoagulation with direct oral anticoagulants (DOAC) could provide an alternative to vitamin K antagonists (VKA) for patients with atrial fibrillation (AF) undergoing bioprosthetic heart valve replacement or valve repair.

METHODS AND RESULTS

The aim of this meta-analysis was to review the safety and efficacy of DOAC in patients with surgical implanted bioprosthetic heart valves or valve repairs and AF including data from six clinical trials with a total of 1,857 patients. The efficacy and safety data of DOAC and VKA were pooled to perform random-effects meta-analyses using the Mantel-Haenszel method with pooled risk ratios (RR) and 95% confidence interval (CI). A trial sequential analysis (TSA) was performed to assess statistical robustness. Death caused by cardiovascular cause or thromboembolic events were comparable (RR 0.67, 95% CI: 0.42-1.08; p = 0.10) as DOAC significantly reduced the risk for major bleeding (RR 0.55, 95% CI: 0.35-0.88; p = 0.01) and thromboembolic stroke or systemic embolism rates (RR 0.54, 95% CI: 0.32-0.90; p = 0.02). Rates for intracranial bleeding and hemorrhagic stroke (RR 0.27, 95% CI: 0.07-0.99; p = 0.05) show a trend toward fewer events in the DOAC group. Outcomes for major or minor bleeding events and all-cause mortality were comparable for DOAC and VKA.

CONCLUSION

Cumulative data analysis reveals that DOAC may provide an effective and safe alternative to VKA in patients with AF after surgically implanted bioprosthetic heart valves or repair with AF. Within a relatively heterogeneous study population, this meta-analysis shows a risk reduction of major bleedings and thromboembolic stroke or systemic embolisms for DOAC.

Direct Oral Anticoagulants in Patients with Atrial Fibrillation and Bioprosthetic Valves-A Systematic Review and Meta-analysis

Oral anticoagulation is recommended for patients with atrial fibrillation and an elevated stroke risk. Direct oral anticoagulants (DOACs) are generally preferred over vitamin K antagonists. Nonetheless, there controversy persists regarding whether DOACs should be used in patients with atrial fibrillation and bioprosthetic valves. Therefore, we conducted this systematic review and meta-analysis to assess the safety and efficacy of DOACs compared to warfarin in this patient population. We performed a systematic search of the MEDLINE and PubMed Central databases for relevant articles. The incidence rate and risk ratio (RR) of all-cause mortality, cardiovascular mortality, ischemic stroke/systemic thromboembolism, hemorrhagic stroke/intracranial bleeding, major bleeding, and minor bleeding were calculated. A total of eight studies were included, including 5,300 patients (stratified as 1,638 patients in the DOAC arm and 3,662 patients in the warfarin arm). There was no significant difference in the rate of stroke/systemic thromboembolism [RR: 0.85; 95% confidence interval (CI): 0.43–1.69], all-cause mortality (RR: 0.77; 95% CI: 0.53–1.11), or cardiovascular death (RR: 0.81; 95% CI: 0.40–1.63) between DOACs and warfarin. Major bleeding and hemorrhagic stroke/intracranial bleeding were similar between both treatment arms (RR: 0.61; 95% CI: 0.35–1.06 and RR: 0.27; 95% CI: 0.06–1.13, respectively). In conclusion, DOACs are safe and effective in patients with atrial fibrillation and bioprosthetic valves. Future large-scale randomized studies are warranted to confirm this observation.

Impact of mitral versus aortic bioprosthetic valve position on thromboembolism and bleeding risk in patients with atrial fibrillation

BACKGROUND

The impact of valve position on thromboembolic and bleeding events in patients with atrial fibrillation (AF) and bioprosthetic valves is uncertain.

METHODS

We analyzed 159 patients with AF after surgical single-valve replacement from the BPV-AF registry (Retro) (UMIN000034198), which was a multicenter, retrospective, observational registry that enrolled 214 patients with AF and bioprosthetic valves to assess differences in bioprosthetic valve position. Baseline characteristics and clinical outcomes were compared on the basis of the position of aortic or mitral bioprosthetic valves. The primary efficacy endpoint was stroke or systemic embolism, and the primary safety endpoint was major bleeding.

RESULTS

There were 85 patients (53.5%) in the aortic valve (AV) group and 74 patients (46.5%) in the mitral valve (MV) group. The MV group had a lower body weight and a higher prevalence of prior major bleeding compared with the AV group. Thromboembolic and bleeding risk scores and the administration of antithrombotic agents were not significantly different between the groups. The primary efficacy endpoint was not significantly different [AV group: 8.2%; 2.25/100 person-years (PY); MV group: 4.1%; 1.01/100 PY] (log-rank, p = 0.23). The primary safety endpoint was significantly higher in the MV group (17.6%; 4.54/100 PY) compared with the AV group (5.9%; 1.59/100 PY) (log-rank, p = 0.049). The adjusted hazard ratio of the primary safety endpoint in the MV group relative to the AV group was 2.71 (95% confidence interval 0.86-8.54, p = 0.09).

CONCLUSIONS

In Japanese patients with AF and bioprosthetic valves, thromboembolic risk does not differ on the basis of valve position. Bleeding risk is higher in patients with MV bioprostheses, although valve position itself might not be an independent predictor for bleeding.

Direct oral anticoagulants versus vitamin K antagonists in patients with atrial fibrillation and bioprosthetic valves: A meta-analysis

BACKGROUND

The optimal anticoagulation strategy for patients with bioprosthetic valves and atrial fibrillation remains uncertain. We conducted a meta-analysis using updated evidence comparing direct anticoagulants (DOACs) and vitamin K antagonists (VKAs) in patients with bioprosthetic valves and atrial fibrillation.

METHODS

Medline and Embase were searched through March 2021 to identify randomized controlled trials (RCTs) and observational studies investigating the outcomes of DOAC therapy and VKA therapy in patients with bioprosthetic valves and atrial fibrillation. The outcomes of interest were all-cause death, major bleeding, and stroke or systemic embolism.

RESULTS

Our analysis included 4 RCTs and 6 observational studies enrolling a total of 6405 patients with bioprosthetic valves and atrial fibrillation assigned to a DOAC group (n = 2142) or a VKA group (n = 4263). Pooled analysis demonstrated the similar rates of all-cause death (hazard ratio [HR], 0.90; 95% confidence interval [CI], 0.77-1.05; P = .18; I² = 0%) in the DOAC and VKA groups. However, the rate of major bleeding was significantly lower in the DOAC group (HR, 0.66; 95% CI, 0.48-0.89; P = .006; I² = 0%), whereas the rate of stroke or systemic embolism was similar in the 2 groups (HR, 0.72; 95% CI, 0.44-1.17; P = .18; I² = 39%).

CONCLUSIONS

DOAC might decrease the risk of major bleeding without increasing the risk of stroke or systemic embolism or all-cause death compared with VKA in patients with bioprosthetic valves and atrial fibrillation.

The Characteristics, Long-Term Outcomes, Risk Factors, and Antithrombotic Therapy in Chinese Patients With Atrial Fibrillation and Bioprosthetic Valves

Introduction: There were few data about the clinical profiles and long-term outcomes in Chinese patients with atrial fibrillation (AF) and bioprosthetic valves.

Methods: The retrospective study enrolled 903 patients with bioprosthetic valve replacement at our hospital and discharged with a diagnosis of AF from January 2010 to December 2018.

Results: The median age was 65.6 (61.9–69.1) years, and 548 (60.7%) patients were women. During a follow-up period of 3.84 (2.64–5.51) years, 68 (1.8 per 100 person-years) patients died, 81 (2.1 per 100 person-years) patients developed thromboembolism, and 23 (0.6 per 100 person-years) patients experienced major bleeding. The CHA₂DS₂-VASc score, as a categorical variable (low, moderate, or high risk), predicted the risk of thromboembolism with the C-statistic of 0.6 (95% CI: 0.511–0.689, p = 0.046). The incidence of the CHA₂DS₂-VASc score increment was 11.6 per 100 person-years, and the annual reclassification rate of stroke risk (from a low or moderate group to a higher group) was 12.7%. The current proportion of oral anticoagulants was 52.3, 59, and 63.2%, respectively, in the low, moderate, and high stroke risk groups. Age (OR: 1.04, 95% CI: 1.01–1.06, p = 0.01), left atrial size (OR: 1.05, 95% CI: 1.03–1.08, p < 0.001), and rheumatic heart disease (OR: 1.49, 95% CI: 1.05–2.10, p = 0.025) were positively associated with the use of oral anticoagulants. The history of chronic kidney disease (OR: 0.20, 95% CI: 0.05–0.76, p = 0.018), prior surgical ablation (OR: 0.33, 95% CI: 0.24–0.47, p < 0.001), and antiplatelet agent use (OR: 0.08, 95% CI: 0.05–0.13, p < 0.001) were inversely related to the use of oral anticoagulants. Higher admission estimated glomerular filtration rate (HR: 0.515, 95% CI: 0.311–0.853, p = 0.01), left ventricular ejection fraction (HR: 0.961, 95% CI: 0.931–0.992, p = 0.014), concomitant surgical ablation (HR: 0.348, 95% CI: 0.171–0.711, p = 0.004), and rheumatic heart disease history (HR: 0.515, 95% CI: 0.311–0.853, p = 0.01) were associated with a lower risk of death. Surgical ablation (HR: 0.263, 95% CI: 0.133–0.519, p < 0.001) and oral anticoagulants (HR: 0.587, 95% CI: 0.375–0.918, p = 0.019) were related to a lower risk of thromboembolism.

Conclusion: Chinese patients with AF and bioprosthetic valve(s) were relatively young and had a high prevalence of rheumatic heart disease with few comorbidities. The percentage of mitral bioprosthetic valve replacement was high. The proportion of concomitant surgical ablation or surgical left atrial appendage occlusion or exclusion was relatively low. The thromboembolic events were the major long-term adverse events. The anticoagulation therapy was underused in patients at moderate or high stroke risk. The CHA₂DS₂-VASc score was verified to be used for predicting stroke risk in this population. The stroke risk dynamically changed; it needed to be reestimated once the risk factor changed.