Non-Vitamin K Antagonist Oral Anticoagulants in Patients with Atrial Fibrillation and Valvular Heart Disease

Effect of direct oral anticoagulants in patients with atrial fibrillation with mitral or aortic stenosis: A review

Background

Several studies have summarized the clinical performance of direct oral anticoagulants (DOACs) in atrial fibrillation (AF) patients with mitral stenosis or aortic stenosis. The significance of this review was to provide clinicians the latest update of the clinical application of DOACs in managing this specific population.

Methods

Literatures from the PubMed database up to July 2022 were screened for inclusion. Studies on the effect of DOACs in patients suffering from AF with mitral or aortic stenosis were assessed for further selection.

Results

Results from four studies were gathered: the RISE MS trial, the DAVID-MS study, and two observational studies. In the Korean observational study with a 27-month follow-up duration and a sample population consisted of patients with mitral stenosis and AF, the thromboembolic events happened at a rate of 2.22%/ year in the DOAC group and 4.19%/year in the warfarin group (adjusted hazard ratio: 0.28; 95% CI: 0.18–0.45). Intracranial hemorrhage occurred at rates of 0.49% and 0.93% in the DOAC and the warfarin groups, respectively (adjusted hazard ratio: 0.53; 95% CI: 0.22–1.26). In the Danish observational study, which had a sample pool with AF patients with aortic stenosis, reported that the adjusted hazard ratios for thromboembolism and major bleeding were 1.62 (95% CI, 1.08–2.45) and 0.73 (95% CI, 0.59–0.91) for DOACs compared with warfarin during 3 years of follow-up. In the RISE-MS trial involving AF patients with mitral stenosis, there were no differences in ischemic stroke, systemic embolic events, or major bleeding between the rivaroxaban vs. warfarin groups during a 1-year follow-up as well as equal rate of increased thrombogenicity in the left atrial appendage at 6 months. The rate of silent cerebral ischemia at 12 months was higher in the warfarin group (17.6%) than that in the rivaroxaban group (13.3%).

Conclusions

Current published studies supported DOACs' effectiveness in preventing thromboembolism in patients of AF with mitral or aortic stenosis. Further clinical trials could confirm these findings.

Effectiveness and safety of non-vitamin K direct oral anticoagulants in atrial fibrillation patients with bioprosthetic valve

Background

Non-vitamin K direct oral anticoagulant (DOAC) is effective for prevention of embolic events in nonvalvular atrial fibrillation (AF) patients. However, the effectiveness and safety of DOAC in AF patients who have bioprosthetic heart valve (BPHV) is largely unknown.

Methods

We retrospectively identified patients with AF and BPHV, using the diagnostic code and medical device and surgery information from the Korean National Health Insurance Service database, between 2013 and 2018. A 1:2 propensity score-matched cohort (n = 724 taking warfarin; n = 362 taking DOAC) was constructed and analyzed for the primary clinical outcome, a composite of ischemic stroke and systemic embolism. Important secondary outcomes included major bleeding, all-cause death, and the net clinical outcome, defined as a composite of all embolic events, major bleeding, and death.

Results

The mean age was 78.9±6.8 years old, and 45% (n = 489) were male. The mean CHA2DS2-VASc score was 4.7±1.4. DOAC was non-inferior to warfarin for preventing ischemic stroke and systemic embolism (hazard ratio [HR] 1.14, 95% confidence interval [CI] 0.56–2.34), major bleeding (HR 0.80, 95% CI 0.32–2.03) and all-cause death (HR 1.09, 95% CI 0.73–1.63). As for the net clinical outcome, DOAC was also similar to warfarin (HR 1.06, 95% CI 0.76–1.47). These outcomes were not different in various subgroups analyzed.

Conclusion

In this nationwide Korean AF population with a BPHV, DOAC was at least as effective and safe as warfarin for the prevention of systemic embolic events. These results suggest that DOAC may be an excellent alternative to warfarin in AF patients with BPHV.

Novel oral anticoagulants versus vitamin K antagonists in patients with atrial fibrillation after transcatheter aortic valve replacement: A systematic review and meta-analysis

BACKGROUND

The efficacy and safety of novel oral anticoagulants (NOACs) compared to the current guideline-recommended vitamin K antagonists (VKAs) in atrial fibrillation (AF) patients undergoing transcatheter aortic valve replacement (TAVR) has not been well established. We pooled evidence from all available studies to assess the risks and benefits of this drug class.

METHODS

We queried electronic databases (MEDLINE, Scopus, and Cochrane central) up until January 28th, 2022 for studies comparing NOACs to VKAs in AF patients undergoing TAVR. Results from studies were presented as risk ratios (RR) and pooled using a random-effects model. Subgroup analysis by study design and meta-regression analysis were performed to explore heterogeneity.

RESULTS

A total of 12 studies (3 RCTs and 9 observational) containing 12,203 patients (mean age 81.2 years; 50.5% men) were identified and included in the analysis. Pooled analysis revealed no significant difference between NOACs and VKAs in terms of stroke or systemic embolism (RR: 0.78; p = 0.18), major bleeding (RR: 0.84; p = 0.32), intracranial hemorrhage (RR 0.61; p = 0.06), all-cause mortality (RR: 0.69; p = 0.07), and myocardial infarction (RR: 1.60; p = 0.24) at a mean length of follow-up of 15.1 months. RCTs and observational studies did not significantly differ across outcomes on subgroup analysis. Meta-regression analysis found heterogeneity in all-cause mortality to be significantly explained by percentage of males (coefficient: 0.049, p = 0.007), mean age (coefficient: 0.221, p < 0.001), and CHA2DS2-VASc score (coefficient: -1.657, p < 0.001).

CONCLUSIONS

This meta-analysis suggests that outcomes with NOACs do not significantly differ compared to VKAs following TAVR in patients with AF.

2021 Focused update of the 2017 consensus guidelines of the Asia Pacific Heart Rhythm Society (APHRS) on stroke prevention in atrial fibrillation

The consensus of the Asia Pacific Heart Rhythm Society (APHRS) on stroke prevention in atrial fibrillation (AF) has been published in 2017 which provided useful clinical guidance for cardiologists, neurologists, geriatricians, and general practitioners in Asia-Pacific region. In these years, many important new data regarding stroke prevention in AF were reported. The Practice Guidelines subcommittee members comprehensively reviewed updated information on stroke prevention in AF, and summarized them in this 2021 focused update of the 2017 consensus guidelines of the APHRS on stroke prevention in AF. We highlighted and focused on several issues, including the importance of AF Better Care (ABC) pathway, the advantages of non-vitamin K antagonist oral anticoagulants (NOACs) for Asians, the considerations of use of NOACs for Asian patients with AF with single 1 stroke risk factor beyond gender, the role of lifestyle factors on stroke risk, the use of oral anticoagulants during the "coronavirus disease 2019" (COVID-19) pandemic, etc. We fully realize that there are gaps, unaddressed questions, and many areas of uncertainty and debate in the current knowledge of AF, and the physician's decision remains the most important factor in the management of AF.

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.

Effectiveness and safety of non-vitamin K antagonist oral anticoagulants in Asian patients with atrial fibrillation and valvular heart disease

OBJECTIVE

We compared the effectiveness and safety outcomes of non-vitamin K antagonist oral anticoagulants (NOACs) and warfarin in patients with AF and VHD, as these patients have been partially excluded from clinical trials.

METHODS

This retrospective cohort study was conducted using the National Health Insurance Research Database in Taiwan. Patients with AF and VHD and above 20 years of age, who were prescribed oral anticoagulants such as warfarin, dabigatran, rivaroxaban, and apixaban, were included. Propensity score matching was performed to balance intergroup differences. The Cox proportional hazards model was used to compare the effectiveness and safety of warfarin and NOACs.

RESULTS

We included 5833 NOAC-warfarin pairs, 3001 dabigatran-warfarin pairs and 2595 rivaroxaban-warfarin pairs. Warfarin and NOACs had similar risk of ischemic stroke (hazard ratio [HR], 0.92; 95% confidence interval [CI], 0.79-1.06; p = .25) and bleeding events (HR, 0.90; 95% CI, 0.78-1.02; p = .10). NOACs showed reduced risk of venous thromboembolism, intracranial hemorrhage, and mortality (HR and 95% CI, 0.39 [0.20-0.77], p = .01; 0.62 [0.45-0.84], p < .01; and 0.47 [0.41-0.53], p < .01, respectively). The benefit of NOACs in reducing the risk of venous thromboembolism was mainly driven by dabigatran, and the benefit of reducing the risk of intracranial hemorrhage and mortality was observed in both dabigatran and rivaroxaban users.

CONCLUSIONS

NOACs had a comparable risk of ischemic stroke and bleeding in patients with AF and VHD, and reduced the risk of venous thromboembolism, intracranial hemorrhage, and mortality, compared to warfarin. Therefore, NOAC is an effective and safe alternative to warfarin in these patients.

Thromboembolic and bleeding outcomes in patients with atrial fibrillation and valvular heart disease: A descriptive nationwide cohort study

AIMS

The risks of thromboembolism and bleeding in patients with atrial fibrillation (AF) and valvular heart disease (VHD) are sparsely described. We described the risk of events in non-anticoagulated and anticoagulated patients with AF and VHD according to the evaluated heart valves, rheumatic or artificial valve classification (EHRA classification), EHRA Type 1 and Type 2 VHD, and within subgroups of EHRA Type 1 and Type 2 VHD.

METHODS AND RESULTS

Cohort study of AF patients with coexisting VHD, identified in nationwide Danish registries from 2000 to 2018. Risk of thromboembolism and bleeding after 1 year of follow-up were calculated in each group. We identified 28 770 incident AF patients with VHD. Not surprisingly, we observed the highest risks of thromboembolism in the non-anticoagulated AF patients with EHRA Type 1 and Type 2 VHD (4.9% vs 2.6% and 3.2% vs 1.9%) and the highest risks of bleeding in the anticoagulated AF patients with EHRA Type 1 and Type 2 VHD (6.6% vs 4.3% and 6.1% vs 4.9%). However, within the subgroups of AF patients with EHRA Type 1 and Type 2 VHD, we observed a large proportion of non-anticoagulated patients (32.9%-49.2%), despite a CHA₂ DS₂ -VASc score of 2≤ in the majority of these patients (81.9%-95.6%).

CONCLUSIONS

When using data reflecting contemporary clinical practice, we observed markedly different risks of thromboembolism and bleeding in EHRA Type 1 and Type 2 VHD. Additionally, we observed a potential underuse of oral anticoagulation within the subgroups of AF patients with EHRA Type 1 and Type 2 VHD, underlining need for further attention on this patient group.

Non-Vitamin K Antagonist Oral Anticoagulants and the Gastrointestinal Bleeding Risk in Real-World Studies

In the present study, we aimed to provide evidence from high-quality real world studies for a comprehensive and rigorous analysis on the gastrointestinal bleeding (GIB) risk for non-vitamin K antagonist oral anticoagulants (NOACs). We performed a systematic search of MEDLINE, EMBASE and PUBMED, and of 286 records screened, we included data from 11 high-quality real-world studies, coordinated by independent research groups over the last 3 years, that reported major GIB events in patients given NOACs or vitamin K antagonists for patients with nonvalvular atrial fibrillation. The lowest risk of gastrointestinal bleeding was with apixaban compared with warfarin (hazard ratio (HR) for GIB for apixaban ranging between 0.45 (95% confidence interval (CI) 0.34 to 0.59) and 1.13 (95% CI 0.79 to 1.63)). Apixaban was associated with a lower risk of GI bleeding than dabigatran ((HR ranging between 0.39 (95% CI 0.27 to 0.58) and 0.95 (95% CI 0.65 to 1.18)) or rivaroxaban ((HR ranging between 0.33 (95% CI 0.22 to 0.49) and 0.82 (95% CI 0.62 to 1.08)). The results of our study confirm a low or a similar risk for major GIB between patients receiving apixaban or dabigatran compared with warfarin, and apixaban appears to be associated with the lowest risk of GIB.