Efficacy and safety of edoxaban in patients early after surgical bioprosthetic valve implantation or valve repair: A randomized clinical trial

Efficacy and Safety of Edoxaban in Anticoagulant Therapy Early After Surgical Bioprosthetic Valve Replacement: Rationale and Design of the ENBALV Trial

BACKGROUND AND PURPOSE

Anticoagulant therapy with vitamin K antagonists is recommended within 3 to 6 months after bioprosthetic valve replacement to prevent thromboembolic events. However, data regarding whether direct oral anticoagulants can be an alternative to warfarin in such patients are limited. The purpose of this study is to compare the efficacy and safety of edoxaban versus warfarin within 3 months after bioprosthetic valve replacement.

METHODS

The ENBALV trial is an investigator-initiated, phase 3, randomized, open-label, multicenter study. It involves patients aged 18 to 85 years undergoing bioprosthetic valve replacement at the aortic and/or mitral position. They are randomized 1:1 to receive either edoxaban or warfarin. Administration of edoxaban or warfarin is to be continued for 12 weeks after surgery. The primary outcome is the occurrence rate of stroke or systemic embolism at 12 weeks after surgery. The net clinical outcome is a composite of stroke, systemic embolism, or major bleeding, which is included in the secondary outcomes.

CONCLUSION

The ENBALV trial demonstrates the efficacy and safety of edoxaban compared with warfarin in patients early after bioprosthetic valve replacement, including patients with sinus rhythm, which will bring a significant benefit to patients in clinical practice.

TRIAL REGISTRATION

Japan Registry of Clinical Trials (jRCT) 2051210209. 30 Mar 2022 https://jrct.niph.go.jp/latest-detail/jRCT2051210209 .

A Randomized Trial Comparing Standard of Care to Bayesian Warfarin Dose Individualization

The quality of warfarin treatment may be improved if management is guided by the use of models based upon pharmacokinetic-pharmacodynamic theory. A prospective, two-armed, single-blind, randomized controlled trial compared management aided by a web-based dose calculator (NextDose) with standard clinical care. Participants were 240 adults receiving warfarin therapy following cardiac surgery, followed up until the first outpatient appointment at least 3 months after warfarin initiation. We compared the percentage of time spent in the international normalized ratio acceptable range (%TIR) during the first 28 days following warfarin initiation, and %TIR and count of bleeding events over the entire follow-up period. Two hundred thirty-four participants were followed up to day 28 (NextDose: 116 and standard of care: 118), and 228 participants (114 per arm) were followed up to the final study visit. Median %TIR tended to be higher for participants receiving NextDose guided warfarin management during the first 28 days (63 vs. 56%, P = 0.13) and over the entire follow-up period (74 vs. 71%, P = 0.04). The hazard of clinically relevant minor bleeding events was lower for participants in the NextDose arm (hazard ratio: 0.21, P = 0.041). In NextDose, there were 89.3% of proposed doses accepted by prescribers. NextDose guided dose management in cardiac surgery patients requiring warfarin was associated with an increase in %TIR across the full follow-up period and fewer hemorrhagic events. A theory-based, pharmacologically guided approach facilitates higher quality warfarin anticoagulation. An important practical benefit is a reduced requirement for clinical experience of warfarin management.

Concomitant interventions in mitral valve surgery - A European perspective

INTRODUCTION

In recent years, major findings on concomitant procedures and anticoagulation management have occurred in Mitral Valve (MV) surgery. Therefore, we sought to evaluate the current practices in MV interventions across Europe.

METHODS

In October 2021, all national cardio-thoracic societies in the European region were identified following an electronic search and sent an online survey of 14 questions to distribute among their member consultant/attending cardiac surgeons.

RESULTS

The survey was completed by 91 consultant/attending cardiac surgeons across 12 European countries, with 78% indicating MV repair as their specialty area. 57.1% performed >150 operations/year and 71.4% had 10+ years of experience.Concomitant tricuspid valve repair is performed for moderate tricuspid regurgitation (TR) by 69% of surgeons and for mild TR by 26.3%, both with annular diameter >40 mm. 50.6% indicated ischaemic MV surgery in patients undergoing CABG if moderate mitral regurgitation with ERO >20 mm2 and regurgitant volume >30 mL, and 45.1% perform it if severe MR with ERO >40 mm2 and regurgitant volume >60 mL. For these patients the preferred management was: MVR if predictors of repair failure identified (47.2%) and downsizing annuloplasty ring only (34.1%).For atrial fibrillation (AF) in cardiac surgery, 34.1% perform ablation with biatrial lesion and 20% with left sided only. 62.6% perform concomitant Left Atrial Appendage (LAA) Occlusion irrespective of AF ablation with a left atrial clip. A wide variability in anticoagulation strategies for MV repair and bioprosthetic MV valve was reported both for patients in sinus rhythm and AF.

CONCLUSION

These results demonstrate a variable practice for MV surgery, and a degree of lack of compliance with surgical intervention guidelines and anticoagulation strategy.

Direct Oral Anticoagulation Versus Warfarin in Patients with Atrial Fibrillation and Bioprosthetic Heart Valves: a Retrospective, Real-World Cohort Study

OBJECTIVE

In this retrospective cohort study of consecutive patients with atrial fibrillation and surgical or transcatheter bioprosthetic valve, we compared the efficacy and safety of direct oral anticoagulants with warfarin.

METHODS

Using linked health administrative databases housed at the Institute for Clinical Evaluative Sciences, we identified consecutive patients in Ontario (Canada) 65 years of age or older with AF who underwent bioprosthetic valve replacement between 1 April 2012 and 31 March 2017. We created a time-varying Cox model to examine the relationship between the type of anticoagulant and time to thrombotic or bleeding events after adjustment for baseline risk of thrombosis using the CHA2DS2-VASc score and risk of bleeding using the HAS-BLED scores. We conducted prespecified subgroup analyses according to whether valve implantation was surgical or transcatheter.

RESULTS

We identified 2245 eligible patients. The mean age was 79 years, 41% were female, and 39% had transcatheter aortic valve replacement. Risk of death or thrombosis was not different between direct oral anticoagulants and warfarin after adjustment for CHA2DS2-VASc score (hazard ratio [HR] 1.02, 95% confidence interval [CI], 0.83-1.25). Risk of death or bleeding was not different between direct oral anticoagulants and warfarin after adjustment for HAS-BLED score (HR 0.89, 95% CI 0.75-1.07). Subgroup analyses of surgical or transcatheter valves were consistent with overall results.

CONCLUSIONS

In a real-world population of patients with atrial fibrillation and bioprosthetic valve replacement, we found no difference between direct oral anticoagulants and warfarin with regard to the risk of thrombosis or bleeding.

Antithrombotic Treatment After Transcatheter Valve Interventions: Current Status and Future Directions

PURPOSE

The optimal antithrombotic strategy after transcatheter valve interventions is a subject of ongoing debate. Although there is evidence from randomized trials in patients undergoing transcatheter aortic valve replacement (TAVR), current evidence on optimal antithrombotic management after transcatheter mitral or tricuspid valve interventions is sparse. This article appraises the current evidence on this topic.

METHODS

This narrative review presents key research findings and guideline recommendations, as well as highlights areas for future research.

FINDINGS

After TAVR, randomized trial evidence suggests that single antiplatelet therapy is reasonable for patients without pre-existing indications for oral anticoagulation (OAC). If there is a concurrent indication for OAC, the addition of antiplatelet therapy increases bleeding risk. Whether direct oral anticoagulants achieve better outcomes than vitamin K antagonists is uncertain in this setting. Although OAC has been shown to reduce subclinical leaflet thrombosis (which may progress to structural valve degeneration), bleeding events are unacceptably high. There is a lack of randomized trial data comparing antithrombotic strategies after transcatheter mitral or tricuspid valve replacement or after mitral or tricuspid transcatheter edge-to-edge repair. Single antiplatelet therapy after mitral or tricuspid transcatheter edge-to-edge repair may be appropriate, whereas at least 3 months of OAC is suggested after transcatheter mitral valve replacement or transcatheter tricuspid valve replacement.

IMPLICATIONS

Randomized studies are warranted to address the knowledge gaps in antithrombotic therapy after transcatheter valve interventions and to optimize outcomes.

Thromboembolic and bleeding events after valvular intervention in patients with atrial fibrillation

AIM

To assess outcomes after cardiac surgery with biological valve replacement, valve repair or transcatheter aortic valve implantation (TAVI) in patients with atrial fibrillation (AF) in accordance with oral anticoagulant (OAC) treatment.

METHODS

All patients in Sweden undergoing valvular intervention with AF were included. Associations between OAC exposure and cardiovascular (CV) events (composite of CV death, ischaemic stroke or systemic embolism) and major bleeding were investigated using Cox regression analysis. The analysis was separated in time periods of 0-3 and 3-12 months after discharge.

RESULTS

4730 patients were included in the first time period, 54.0% had received a surgical biological valve prosthesis, 23.8% valve repair and 22.2% TAVI. Exposure to warfarin (comparator) was 62.3%, to non-vitamin K antagonist oral anticoagulants (NOACs) 10.0% and to no OAC 27.7%. NOAC exposure was associated with similar risk of the composite CV outcome and major bleeding from 0 to 3 months. No OAC was associated with increased risk of the composite CV outcome (HR 1.71; 95% CI 1.26 to 2.32) and similar risk of major bleeding. Further analysis of the bioprosthetic valve replacement subgroup indicated increased risk of CV death when exposed to NOAC (HR 2.58; 95% CI 1.15 to 5.78) and no OAC (HR 2.82; 95% CI 1.65 to 4.82) compared with warfarin from 0 to 3 months. No differences were seen between 3 and 12 months.

CONCLUSION

In this registry-based cohort study of patients with AF with severe valvular heart disease undergoing various valvular interventions, NOAC appears to be comparable with warfarin regarding efficacy and safety. Patients not receiving OAC had higher risk of CV events. NOAC was associated with increased CV death compared with warfarin in the surgical bioprosthetic valve replacement subgroup, illustrating the importance of being cautious when extrapolating data from one patient group to another. Further studies comparing NOAC and warfarin in the early postoperative phase are warranted, especially following surgical bioprosthetic valve replacement.

Comparison of Direct Oral Anticoagulants vs Vitamin K Antagonists After Transcatheter Mitral Valve Replacement

BACKGROUND

There is currently no established recommendation for antithrombotic treatment following transcatheter mitral valve replacement (TMVR). However, based on the analogy with surgical mitral bioprosthesis, vitamin K antagonists (VKAs) are predominantly used.

OBJECTIVES

The purpose of this study was to compare bleeding and thrombotic events associated with direct oral anticoagulants (DOACs) or VKAs in a prospective cohort of TMVR patients.

METHODS

We enrolled consecutive patients who underwent transseptal TMVR using a SAPIEN family prosthesis at our center between 2011 and 2023. The primary outcome was the occurrence of bleeding. VKAs were administered to patients until October 2019, after which DOACs were prescribed. The median follow-up was 4.7 months (Q1-Q3: 2.6-6.7 months).

RESULTS

A total of 156 patients were included. The mean age was 65 ± 18.5 years, and 103 patients (66%) were women. The median EuroSCORE II was 7.48% (Q1-Q3: 3.80%-12.97%). Of the participants, 20.5% received DOACs and 79.5% were treated with VKAs. The primary outcome was observed in 50 (40%) patients in the VKA group and 3 (9%) patients in the DOAC group (adjusted HR: 0.21; 95% CI: 0.06-0.74; P = 0.02). Treatment with DOAC was associated with a shorter length of hospital stay. No significant differences were found in terms of thrombotic events, major vascular complications, stroke, or death.

CONCLUSIONS

The use of DOACs after TMVR, compared with VKAs, appears to reduce the risk of bleeding complications and decrease the length of hospital stay for patients, without a significant increase in the risk of thrombotic events.

Selection of Non-vitamin K Antagonist Oral Anticoagulant for Stroke Prevention in Atrial Fibrillation Based on Patient Profile: Perspectives from Vietnamese Experts. Part 2

Part 1 of this review provided an overview of AF in Vietnam, with a particular focus on primary and secondary stroke prevention. Part 2 explores the management of AF in special, high-risk and clinically common patient populations, including those with renal impairment, diabetes, the elderly, and those with coronary artery disease. Furthermore, Part 2 addresses the challenges posed by patients with AF who have a bioprosthetic valve, a group situated in a grey area of consideration. Managing AF in these patient groups presents unique clinical challenges that require careful consideration. Physicians are tasked with addressing specific clinical questions to identify the optimal anticoagulation strategy for each individual. To inform these decisions, subgroup analyses from pivotal studies are presented alongside real-world data derived from clinical practice. By synthesising available information and considering the nuanced clinical context, the aim is to provide informed perspectives that align with current medical knowledge and contribute to the enhancement of patient care in these challenging scenarios.

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.

Antithrombotic Therapy for Primary and Secondary Prevention of Ischemic Stroke: JACC State-of-the-Art Review

Stroke is a devastating condition with significant morbidity and mortality worldwide. Antithrombotic therapy plays a crucial role in both primary and secondary prevention of stroke events. Single or dual antiplatelet therapy is generally preferred in cases of large-artery atherosclerosis and small-vessel disease, whereas anticoagulation is recommended in conditions of blood stasis or hypercoagulable states that mostly result in red thrombi. However, the benefit of antithrombotic therapies must be weighed against the increased risk of bleeding, which can pose significant challenges in the pharmacological management of this condition. This review provides a comprehensive summary of the currently available evidence on antithrombotic therapy for ischemic stroke and outlines an updated therapeutic algorithm to support physicians in tailoring the strategy to the individual patient and the underlying mechanism of stroke.

Direct oral anticoagulants versus vitamin K antagonists: Which one is more effective in atrial fibrillation

BACKGROUND

The optimal approach for anticoagulation in patients with bioprosthetic valves and atrial fibrillation (AF) remains a subject of debate. A meta-analysis using updated evidence to evaluate the efficacy and safety of direct oral anticoagulants (DOACs) compared to vitamin K antagonists (VKAs) in patients with AF and bioprosthetic valves to address this controversy.

METHODS

A comprehensive search was conducted in multiple databases, including PubMed, Scopus, Web of Science, ProQuest, and the Cochrane Central Register of Controlled Trials, up until March 2023. The search aimed to identify relevant randomized controlled trials (RCTs) that examined the efficacy and safety outcomes of both direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs) in patients with bioprosthetic valves and atrial fibrillation. The primary outcomes of interest were major bleeding and all-cause mortality.

RESULTS

Our study demonstrated that despite the difference was not significant, the hazard of all-cause mortality was 2.5% higher in the DOAC group (HR = 1.03, 95% CI = [0.88, 1.19], p-value = .75). Similarly, the hazard of stroke (HR = 1.03, 95% CI = [0.87, 1.32], p-value = .71) and major bleeding (HR = 1.11, 95% CI = [0.89, 1.38], p-value = .36) were found to be respectively 3.2 and 10.7% higher in the DOAC group, although the difference was not significant. However, the hazard of intracranial hemorrhage was found to be 28.8 lower in the DOAC treatment group (HR = 0.71, 95% CI = [0.39, 1.31], p-value = .27), which again was not statistically significant.

CONCLUSIONS

Our meta-analysis demonstrates that in patients undergoing bioprosthetic valve surgery and presenting with AF afterward, DOAC and VKA are similar regarding life-threatening and all-cause mortality outcomes, including major bleeding, stroke, and intracranial hemorrhage.

Direct oral anticoagulants versus vitamin K antagonists in the first 3 months after bioprosthetic valve replacement: a systematic review and meta-analysis

OBJECTIVES

We conducted a systematic review and meta-analysis of randomized controlled trials comparing direct oral anticoagulants (DOACs) to vitamin K antagonists (VKAs) in the first 90 days after bioprosthetic valve implantation.

METHODS

We systematically searched Embase, Medline and CENTRAL. We screened titles, abstracts and full texts, extracted data and assessed the risk of bias in duplicate. We pooled data using the Mantel-Haenzel method and random effects modelling. We conducted subgroup analyses based on the type of valve (transcatheter versus surgical) and timing of initiation of anticoagulation (<7 vs >7 days after valve implantation). We assessed the certainty of evidence using the Grading of Recommendations, Assessments, Development and Evaluation approach.

RESULTS

We included 4 studies of 2284 patients with a median follow-up of 12 months. Two studies examined transcatheter valves (1877/2284 = 83%) and 2 examined surgical valves (407/2284 = 17%). We found no statistically significant differences between DOACs and VKAs with regard to thrombosis, bleeding, death or subclinical valve thrombosis. However, there was a subgroup trend towards more bleeding with DOACs when initiated within 7 days of valve implantation.

CONCLUSIONS

In the existing randomized literature on DOACs versus VKAs in the first 90 days after bioprosthetic valve implantation, there appears to be no difference with regard to thrombosis, bleeding or death. Interpretation of the data is limited by small numbers of events and wide confidence intervals. Future studies should focus on surgical valves and should include long-term follow-up to assess any potential impact of randomized therapy on valve durability.

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.

How Did We Get Here? Antithrombotic Therapy after Bioprosthetic Aortic Valve Replacement: A Review

IMPORTANCE

 Aortic stenosis is the most common valvular disease, and more than 90% of patients who undergo aortic valve replacement receive a bioprosthetic valve. Yet optimal antithrombotic therapy after bioprosthetic aortic valve replacement remains uncertain, and guidelines provide contradictory recommendations.

OBSERVATIONS

 Randomized studies of antithrombotic therapy after bioprosthetic aortic valve replacement are small and underpowered. Observational data present opposing, and likely confounded, results. Historically, changes to guidelines have not been informed by high-quality new data. Current guidelines from different professional bodies provide contradictory recommendations despite citing the same evidence.

CONCLUSION

 Insufficient antithrombotic therapy after bioprosthetic aortic valve replacement has serious implications: ischemic stroke, systemic arterial thromboembolism, and clinical and subclinical valve thromboses. Unnecessarily intense antithrombotic therapy, however, increases risk of bleeding and associated morbidity and mortality. Professional bodies have used the current low-quality evidence and generated incongruent recommendations. Researchers should prioritize generating high-quality, randomized evidence evaluating the risks and benefits of antiplatelet versus anticoagulant therapy after bioprosthetic aortic valve replacement.

Can warfarin be replaced by non-vitamin K anticoagulants in prosthetic valves?

INTRODUCTION

Despite the improved safety and efficacy profile of non-Vitamin K Antagonist Oral Anticoagulants (NOACAs), the current guidelines still limit their use to stroke prevention in non-valvular atrial fibrillation (AF) patients and venous thromboembolism prophylaxis and treatment.

AREAS COVERED

In this report, the authors discussed the published data related to NOACs use in prosthetic valves highlighting the proposed mechanisms of NOACs failure and other controversial data regarding their efficacy and safety in prosthetic valves.

EXPERT OPINION

Although NOACs have proven to be even safer and more effective alternatives to vitamin K antagonists (VKAs) in several indications for anticoagulation, the data regarding their safety and efficacy in prosthetic heart valves is still debatable. The controversial data regarding NOACs use in prosthetic valves renders it difficult to define specific guideline-recommendation for safe and efficient use in this population. The available evidence suggesting that NOACs are as safe and as efficient as VKA regarding thromboembolic prophylaxis and risk of bleeding was primarily based on patients who had undergone bioprosthetic valve and concomitant atrial fibrillation. Further research is warranted to establish if NOACs can be a safer and more efficient alternative to VKAs in patients with prosthetic valves either metallic or bioprosthetic.

Bayesian Meta-analysis of Direct Oral Anticoagulation Versus Vitamin K Antagonists With or Without Concomitant Antiplatelet After Transcatheter Aortic Valve Implantation in Patients With Anticoagulation Indication

Patients undergoing transcatheter aortic valve implantation (TAVI) commonly have co-morbidities requiring anticoagulation. However, the optimal post-procedural anticoagulation regimen is not well-established. This meta-analysis investigates safety and efficacy outcomes of direct oral anticoagulants (DOACs) and Vitamin K Antagonist (VKA), with or without concomitant antiplatelet therapy. We searched EMBASE and MEDLINE for appropriate studies. Subgroup analyses were performed for anticoagulant monotherapy and combined therapy with antiplatelet agents. Eleven studies (6359 patients) were included. Overall, there were no differences between DOACs and VKA for all-cause mortality (Odds Ratio [OR]: .69; Credible Interval [CrI]: .40–1.06), cardiovascular-related mortality (OR: .76; Crl: .13–3.47), bleeding (OR: .95; CrI: .75–1.17), stroke (OR: 1.04; CrI: .65–1.63), myocardial infarction (OR: 1.51; CrI: .55–3.84), and valve thrombosis (OR: .29; CrI: .01–3.54). For DOACs vs VKA monotherapy subgroup, there were no differences in outcomes. For the combined therapy subgroup, there was decreased odds of all-cause mortality in the DOACs group compared with the VKA group (OR: .13; CrI: .02–.65), but no differences for bleeding and stroke. DOACs and VKA have similar safety and efficacy profiles for post-TAVI patients with anticoagulation indication. However, if concomitant antiplatelet therapy is required, DOACs were more favorable than VKA for all-cause mortality.

Are NOACs as safe and efficient as VKA regarding thromboembolic prophylaxis and major bleeding in patients with surgical bioprosthesis and atrial fibrillation within 3 months of surgery?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: ‘Are NOACs as safe and efficient as vitamin K antagonist regarding thromboembolic prophylaxis and major bleeding in patients with surgical bioprosthesis and atrial fibrillation within 3 months of surgery?’ Altogether more than 324 papers were found using the reported search, of which 6 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The RIVER and ENAVLE trials showed non-inferiority of rivaroxaban (regarding mean time free from composite of death, major cardiovascular events or major bleeding at 12 months) and edoxaban (composite of death, clinical thromboembolic events or asymptomatic intracardiac thrombosis; and major bleeding) when compared with vitamin K antagonist. These studies include a low number of patients within 3 months of index surgery and overall low statistical power regarding this particular subgroup of patients. Data derived from lower evidence studies are compatible with the aforementioned findings. The available evidence suggests that non-vitamin K antagonist anticoagulants are as safe and as efficient as vitamin K antagonist regarding thromboembolic prophylaxis and bleeding event rates in patients with surgical bioprosthesis and atrial fibrillation within 3 months of bioprosthesis implantation. However, this evidence is derived from a limited number of studies with important methodological limitations. Expanding non-vitamin K antagonist anticoagulant recommendation to the early postoperative period warrants more confirmatory research.

Switching from warfarin to direct-acting oral anticoagulants: it is time to move forward!

Oral vitamin K antagonists (VKAs), warfarin, have been in routine clinical use for almost 70 years for various cardiovascular conditions. Direct-Acting Oral Anticoagulants (DOACs) have emerged as competitive alternatives for VKAs to prevent stroke in patients with non-valvular atrial fibrillation (AF) and have become the preferred choice in several clinical indications for anticoagulation. Recent guidelines have limited the use of DOACs to patients with non-valvular AF to reduce the risk of cardioembolic complications and to treat venous thromboembolism (VTE). Although emerging evidence is suggestive of its high efficacy, there was a lack of data to support DOACs safety profile in patients with mechanical valve prosthesis, intracardiac thrombi, or other conditions such as cardiac device implantation or catheter ablation. Therefore, several clinical trials have been conducted to assess the beneficial effects of using DOACs, instead of VKAs, for various non-guideline-approved indications. This review aimed to discuss the current guideline-approved indications for DOACs, advantages, and limitations of DOACs use in various clinical indications highlighting the potential emerging indications and remaining challenges for DOACs use. Several considerations are in favour of switching from warfarin to DOACs including superior efficacy, better adverse effect profile, fewer drug-drug interactions, and they do not require frequent international normalized ratio (INR) monitoring. Large randomized controlled trials are required to determine the safety and efficacy of their use in various clinical indications.

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.