Design and Rationale of the RE-DUAL PCI Trial: A Prospective, Randomized, Phase 3b Study Comparing the Safety and Efficacy of Dual Antithrombotic Therapy With Dabigatran Etexilate Versus Warfarin Triple Therapy in Patients With Nonvalvular Atrial Fibrillation Who Have Undergone Percutaneous Coronary Intervention With Stenting

A novel risk score to identify the need for triple antithrombotic therapy in patients with atrial fibrillation undergoing percutaneous coronary intervention: a post hoc analysis of the RE-DUAL PCI trial

BACKGROUND

Current guidelines recommend treating atrial fibrillation (AF) patients who undergo percutaneous coronary intervention (PCI) with triple antithrombotic therapy (TAT) for up to one month in patients at high thrombotic risk. It is unclear how to select these high-risk patients.

AIMS

The aim of this study was to identify patients at high thrombotic risk who might benefit from TAT over double antithrombotic therapy (DAT).

METHODS

This study was a post hoc subanalysis of the RE-DUAL PCI trial. A Cox proportional hazards model was built by stepwise selection of plausible predictor variables for a composite ischaemic endpoint, defined as cardiovascular death, myocardial infarction (MI), stent thrombosis (ST) or ischaemic stroke. The effect of TAT versus DAT was calculated for those patients with the highest proportion of predicted thrombotic risk. A simplified risk score was constructed based on beta-coefficients.

RESULTS

For 209 patients (7.7%) the composite ischaemic endpoint occurred during the first year. The simplified risk score contained six variables. In patients with a score ≥5 (n=154, 5.7%), a significant reduction in the composite of MI and ST was observed with TAT versus DAT (6.3% vs 21.0%, p=0.041), without a penalty in terms of bleeding. In patients at low thrombotic risk, a significant increase in bleeding was observed without a reduction of ischaemic events.

CONCLUSIONS

Our findings support the use of DAT in the majority of patients. A small subgroup of patients might benefit from TAT and we propose a novel clinical risk score to select these patients.

Management of Oral Anticoagulation and Antiplatelet Therapy in Post-Myocardial Infarction Patients with Acute Ischemic Stroke with and without Atrial Fibrillation

The association between atrial fibrillation (AF), acute coronary syndrome (ACS), and stroke is a complex scenario in which the assessment of both thrombotic and hemorrhagic risk is necessary for scheduling an individually tailored therapeutic plan. Recent clinical trials investigating new antithrombotic drugs and dual and triple pathways in high-risk cardiovascular patients have revealed a new therapeutic scenario. In this paper, we review the burden of ischemic stroke (IS) in patients post-myocardial infarction with and without atrial fibrillation and the possible therapeutic strategies from a stroke point of view.

Safety and Efficacy Evaluation of Antithrombotic Therapy with Rivaroxaban and Clopidogrel After PCI in Chinese Patients

Objective

To investigate the efficacy and safety of the antithrombotic therapy using the oral anticoagulant rivaroxaban and clopidogrel in Chinese patients with acute coronary syndrome complicated with atrial fibrillation after percutaneous coronary intervention.

Methods

A total of 100 patients were selected. Patients were randomly divided into two groups: the treatment group (rivaroxaban group) received a therapy of rivaroxaban and clopidogrel. The control group (warfarin group) receivied a combined treatment of warfarin, clopidogrel, and aspirin. The primary outcome endpoint was evaluated based on the adverse cardiac and cerebrovascular events within 12 months.

Results

A total of 8 (8.00%) main adverse cardiac and cerebrovascular events occurred during the 12 months of follow-up, including 5 (9.80%) in the warfarin group and 3 (6.10%) in the rivaroxaban group. The risk of having main adverse cardiac and cerebrovascular events in the two groups was comparable (P = 0.479). A total of 9 patients (9.00%) were found to have bleeding events, among which 8 patients (15.7%) were in the warfarin group, whereas only 1 patient (2.00%) was in the rivaroxaban group. Therefore, the risk of bleeding in the warfarin group was significantly higher than that in the rivaroxaban group (P = 0.047).

Conclusions

In Chinese patients with acute coronary syndrome complicated with atrial fibrillation, the efficacy of the dual therapy of oral anticoagulant rivaroxaban plus clopidogrel after percutaneous coronary intervention was similar to that of the traditional triple therapy combined with warfarin, aspirin and clopidogrel, but it has a better safety property, which has potential to widely apply to antithrombotic therapy after PCI

Natural Coumarins: Exploring the Pharmacological Complexity and Underlying Molecular Mechanisms

Coumarins belong to the benzopyrone family commonly found in many medicinal plants. Natural coumarins demonstrated a wide spectrum of pharmacological activities, including anti-inflammatory, anticoagulant, anticancer, antibacterial, antimalarial, casein kinase-2 (CK2) inhibitory, antifungal, antiviral, Alzheimer's disease inhibition, neuroprotective, anticonvulsant, phytoalexins, ulcerogenic, and antihypertensive. There are very few studies on the bioavailability of coumarins; therefore, further investigations are necessitated to study the bioavailability of different coumarins which already showed good biological activities in previous studies. On the evidence of varied pharmacological properties, the present work presents an overall review of the derivation, availability, and biological capacities of coumarins with further consideration of the essential mode of their therapeutic actions. In conclusion, a wide variety of coumarins are available, and their pharmacological activities are of current interest thanks to their synthetic accessibility and riches in medicinal plants. Coumarins perform the valuable function as therapeutic agents in a range of medical fields.

Antithrombotic Management for Atrial Fibrillation Patients Undergoing Percutaneous Coronary Intervention or With Acute Coronary Syndrome: An Evidence-Based Update

Combined antithrombotic regimens for atrial fibrillation (AF) patients with coronary artery disease, particularly for those who have acute coronary syndrome (ACS) and/or are undergoing percutaneous coronary intervention (PCI), presents a great challenge in the real-world clinical scenario. Conventionally, a triple antithrombotic therapy (TAT), which consists of combined oral anticoagulant therapy to prevent systemic embolism or stroke along with dual antiplatelet therapy to prevent coronary arterial thrombosis (CAT), is used. However, TAT has been associated with a significantly increased risk of bleeding. With the emergence of non-vitamin K antagonist oral anticoagulants (NOACs), randomized controlled trials have demonstrated a better risk-to-benefit ratio of dual antithrombotic therapy (DAT) in combination of a NOAC and with a P2Y12 inhibitor than vitamin K antagonist-based TAT. The results of these studies have impacted the recommendations of current international guidelines, which favor a DAT with a NOAC and P2Y12 inhibitor (especially clopidogrel) in this clinical setting. Additionally, aspirin can be administered during the periprocedural period, while the treatment duration of TAT should be as short as possible. In this article, we summarize the up-to-date evidence regarding antithrombotic regimens for AF patients with PCI or ACS, with a specific focus on the optimal approach and critical discussions of key scientific data and future developments for antithrombotic management in these patients.

The effect of sex on the efficacy and safety of dual antithrombotic therapy with dabigatran versus triple therapy with warfarin after PCI in patients with atrial fibrillation (a RE-DUAL PCI subgroup analysis and comparison to other dual antithrombotic therapy trials)

Background

The RE‐DUAL PCI trial demonstrated that in patients with nonvalvular atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI), dual therapy with dabigatran and a P2Y₁₂ inhibitor, either clopidogrel or ticagrelor, reduced the risk of bleeding without an increased risk of thromboembolic events as compared to triple therapy with warfarin in addition to a P2Y₁₂ inhibitor and aspirin. What remains unclear is whether this effect is consistent between males and females undergoing PCI.

Hypothesis

The reduction in risk of bleeding without increased risk of thromboembolic events with dual therapy with dabigatran and a P2Y₁₂ inhibitor in comparison to triple therapy with warfarin, a P2Y₁₂ inhibitor and aspirin is consistent in females and males.

Methods

The primary safety endpoint was the first International Society on Thrombosis and Hemostasis (ISTH) major bleeding event (MBE) or clinically relevant non‐major bleeding event (CRNMBE). The efficacy endpoint was the composite of death, thromboembolic event (stroke, myocardial infarction, and systemic embolism) or unplanned revascularization. Cox proportional hazard regression analyses were applied to calculate corresponding hazard ratios and interaction p values for each endpoint.

Results

A total of 655 women and 2070 men were enrolled. The risk of major or CRNM bleeding was lower with both dabigatran 110 mg dual therapy and dabigatran 150 mg dual therapy compared with warfarin triple therapy in female and male patients (for 110 mg: females: HR 0.69, 95% CI 0.47–1.01, males: HR 0.46, 95% CI 0.37–0.59, interaction p value: 0.084 and for 150 mg: females HR 0.74, 95% CI 0.48–1.16, males HR 0.71, 95% CI 0.56–0.90, interaction p value: 0.83). There was also no detectable difference in the composite efficacy endpoint of death, thromboembolic events or unplanned revascularization between dabigatran dual therapy and warfarin triple therapy, with no statistically significant interaction between sex and treatment (interaction p values: 0.73 and 0.72, respectively).

Conclusions

Consistent with the overall study results, the risk of bleeding was lower with dabigatran 110 mg and 150 mg dual therapy compared with warfarin triple therapy, and risk of thromboembolic events was comparable with warfarin triple therapy independent of the patient's sex.

Evaluation of Dual Versus Triple Therapy by Landmark Analysis in the RE-DUAL PCI Trial

OBJECTIVES

The aim of this study was to explore the early versus late benefits and risks of dabigatran dual therapy versus warfarin triple therapy in the RE-DUAL PCI (Randomized Evaluation of Dual Antithrombotic Therapy With Dabigatran Versus Triple Therapy With Warfarin in Patients With Nonvalvular Atrial Fibrillation Undergoing Percutaneous Coronary Intervention) trial.

BACKGROUND

Patients with atrial fibrillation who undergo percutaneous coronary intervention are at increased risk for both bleeding and thrombotic events.

METHODS

A total of 2,725 patients with atrial fibrillation underwent percutaneous coronary intervention and were randomized to receive dabigatran 110 mg, or dabigatran 150 mg plus a P2Y₁₂ inhibitor (and no aspirin), or warfarin plus a P2Y₁₂ inhibitor plus aspirin. Landmark analysis was performed at 30 and 90 days.

RESULTS

There was a consistent and large reduction in major or clinically relevant nonmajor bleeding in patients randomized to dual therapy during the first 30 days (110 mg: hazard ratio [HR]: 0.45; 95% confidence interval [CI]: 0.31 to 0.66; p < 0.0001; 150 mg: HR: 0.46; 95% CI: 0.30 to 0.72; p = 0.0006) compared with warfarin triple therapy. There was early net clinical benefit in both dabigatran groups versus warfarin (110 mg: HR: 0.65; 95% CI: 0.47 to 0.88; p = 0.0062; 150 mg: HR: 0.54; 95% CI: 0.37 to 0.79; p = 0.0015), due to larger reductions in bleeding than increased thrombotic events for dabigatran 110 mg and bleeding reduction without increased thrombotic risk for dabigatran 150 mg dual therapy versus warfarin triple therapy. After the removal of aspirin in the warfarin group, bleeding remained lower with dabigatran 110 mg and was similar with dabigatran 150 mg versus warfarin.

CONCLUSIONS

In RE-DUAL PCI, in which patients in the dual-therapy arms were treated with aspirin for an average of only 1.6 days, there was early net clinical benefit with both doses of dabigatran dual therapy, without an increase in thrombotic events with dabigatran 150 mg. This could be helpful in the subset of patients with elevated risk for both bleeding and thrombotic events.

Dabigatran Dual Therapy vs Warfarin Triple Therapy Post-Percutaneous Coronary Intervention in Patients with Atrial Fibrillation With/Without a Proton Pump Inhibitor: A Pre-Specified Analysis of the RE-DUAL PCI Trial

Background and Objective

In patients with atrial fibrillation following percutaneous coronary intervention, if a proton pump inhibitor is used, could that allow the use of warfarin triple therapy, or is there additional reduction in bleeding while using it with dual therapy?

Methods

The RE-DUAL PCI trial randomized 2725 patients with atrial fibrillation post-percutaneous coronary intervention to dabigatran dual therapy (110 or 150 mg twice daily, with clopidogrel or ticagrelor) or warfarin triple therapy (with clopidogrel or ticagrelor, and aspirin for 1–3 months). This prespecified subgroup analysis evaluated risks of a first major bleeding event or clinically relevant non-major bleeding event, all gastrointestinal bleeding, and a composite efficacy endpoint of all-cause mortality/thromboembolic event or unplanned revascularization according to baseline use of a proton pump inhibitor.

Results

Of 2678 analyzed patients, 1641 (61.3%) were receiving a proton pump inhibitor at baseline. Dabigatran 110 and 150 mg dual therapy reduced the risk of major bleeding events or clinically relevant non-major bleeding events vs warfarin triple therapy regardless of proton pump inhibitor use, with comparable risk of the composite efficacy endpoint (all interaction p values > 0.05). For gastrointestinal bleeding, no interaction was observed between study treatment and proton pump inhibitor use (interaction p values 0.84 and 0.62 for dabigatran 110 and 150 mg dual therapy, respectively, vs warfarin triple therapy).

Conclusions

Dabigatran 110 and 150 mg dual therapy reduced the risk of major bleeding events or clinically relevant non-major bleeding events vs warfarin triple therapy, regardless of proton pump inhibitor use at baseline, in patients with atrial fibrillation who underwent percutaneous coronary intervention. Risk of the composite efficacy endpoint appeared to be similar for dabigatran dual therapy vs warfarin triple therapy in patients receiving/not receiving a proton pump inhibitor.

ClinicalTrials.gov unique identifier

NCT02164864.

Video abstract

Electronic supplementary material

The online version of this article (10.1007/s40265-020-01323-x) contains supplementary material, which is available to authorized users.

Complexity of Antiplatelet Therapy in Coronary Artery Disease Patients

Patients with coronary artery disease (CAD) presenting with acute coronary syndrome or undergoing coronary stenting are indicated to treatment with dual antiplatelet therapy (DAPT) combining aspirin with a P2Y12 receptor inhibitor. The management of patients with CAD who present with a complex clinical profile due to multiple comorbidities, and/or undergoing complex interventional procedures, remains challenging as a high risk for both ischemic and bleeding events is often present; hence, the risk-benefit balance on the optimal DAPT duration is difficult to evaluate. The complexity of antiplatelet therapy in CAD patients is due to the fact that this complexity embraces several aspects: the coronary anatomy, the number of vascular districts at risk for atherothrombosis, and patient comorbidities, including global frailty. Recent randomized and epidemiological studies have highlighted subgroups that could benefit from prolonged antithrombotic treatment, as well as frail patients, who may be better suited to a shorter course of therapy. We provide an overview of the current knowledge regarding treatment with DAPT, along with suggestions on its management.

Antithrombotic therapy according to baseline bleeding risk in patients with atrial fibrillation undergoing percutaneous coronary intervention: applying the PRECISE-DAPT score in RE-DUAL PCI

Aims

Patients with atrial fibrillation undergoing coronary intervention are at higher bleeding risk due to the concomitant need for oral anticoagulation and antiplatelet therapy. The RE-DUAL PCI trial demonstrated better safety with dual antithrombotic therapy (DAT: dabigatran 110 or 150 mg b.i.d., clopidogrel or ticagrelor) compared to triple antithrombotic therapy (TAT: warfarin, clopidogrel or ticagrelor, and aspirin). We explored the impact of baseline bleeding risk based on the PRECISE-DAPT score for decision-making regarding DAT vs. TAT.

Methods and results

A score ≥25 points qualified high bleeding risk (HBR). Comparisons were made for the primary safety endpoint International Society of Thrombosis and Haemostasis major or clinically relevant non-major bleeding, and the composite efficacy endpoint of death, thrombo-embolic events, or unplanned revascularization, analysed by time-to-event analysis. PRECISE-DAPT was available in 2336/2725 patients, and 37.9% were HBR. Compared to TAT, DAT with dabigatran 110 mg reduced bleeding risk both in non-HBR [hazard ratio (HR) 0.42, 95% confidence interval (CI) 0.31–0.57] and HBR (HR 0.70, 95% CI 0.52–0.94), with a greater magnitude of benefit among non-HBR (Pint = 0.02). Dual antithrombotic therapy with dabigatran 150 mg vs. TAT reduced bleeding in non-HBR (HR 0.60, 95% CI 0.45–0.80), with a trend toward less benefit in HBR patients (HR 0.92, 95% CI 0.63–1.34; Pint = 0.08). The risk of ischaemic events was similar on DAT with dabigatran (both 110 and 150 mg) vs. TAT in non-HBR and HBR patients (Pint = 0.45 and Pint = 0.56, respectively).

Conclusions

PRECISE-DAPT score appeared useful to identify AF patients undergoing PCI at further increased risk of bleeding complications and may help clinicians identifying the antithrombotic regimen intensity with the best benefit–risk ratio in an individual patient.

Comparison of Dabigatran Plus a P2Y12 Inhibitor With Warfarin-Based Triple Therapy Across Body Mass Index in RE-DUAL PCI

BACKGROUND

Body mass index (BMI) affects drug levels of nonvitamin K antagonist oral anticoagulants. We sought to assess whether BMI affected outcomes in the RE-DUAL PCI trial.

METHODS

RE-DUAL PCI (NCT02164864) evaluated the safety and efficacy of a dual-antithrombotic-therapy regimen using dabigatran (110 mg or 150 mg twice daily and a P2Y₁₂ platelet antagonist) in comparison with triple therapy of warfarin, aspirin, and a P2Y₁₂ platelet inhibitor in 2725 patients with atrial fibrillation who had undergone percutaneous coronary intervention (PCI). We compared the risk of first International Society on Thrombosis and Haemostasis (ISTH)-defined major or clinically relevant nonmajor bleeding events (primary endpoint) and the composite of death, myocardial infarction, stroke, systemic embolism, or unplanned revascularization (main efficacy endpoint) in relation to baseline BMI.

RESULTS

Median (range) BMI was 28.1 (14-66) kg/m². Dabigatran dual therapy versus warfarin triple therapy had relevantly and similarly lower rates of bleeding at both 110 mg and 150 mg twice-daily doses, irrespective of BMI. Thromboembolic event rates appeared consistent across categories of BMI, including those <25 and ≥35 kg/m² (P for interaction: 0.806 and 0.279, respectively).

CONCLUSIONS

The reduction in bleeding with dabigatran dual therapy compared with warfarin triple therapy in patients here evaluated appears consistent across BMI categories.

Predicted effect of ticagrelor on the pharmacokinetics of dabigatran etexilate using physiologically based pharmacokinetic modeling

Dabigatran etexilate (DABE) is a direct oral anticoagulant (DOAC) and may be combined with ticagrelor, a P2Y₁₂ inhibitor with antiplatelet effects. This combination of antiplatelet drugs and anticoagulants would increases the risk of bleeding in patients. In addition, the potential drug interaction may further increase the risk of bleeding. At present, there is scarce research to clarify the results of the interaction between the two. Therefore, we conducted this study to identify the potential impact of ticagrelor on the pharmacokinetics of DABE using physiologically based pharmacokinetic (PBPK) modeling. The models reasonably predicted the concentration-time profiles of dabigatran (DAB), the transformation form after DABE absorption, and ticagrelor. For pharmacokinetic drug-drug interaction (DDI), exposure to DAB at steady state was increased when co-administrated with ticagrelor. The C_max and AUC_0-t of DAB were raised by approximately 8.7% and 7.1%, respectively. Meanwhile, a stable-state ticagrelor co-administration at 400 mg once-daily increased the C_max and AUC_0-t of DAB by approximately 12.8% and 18.8%, respectively. As conclusions, Ticagrelor slightly increased the exposure of DAB. It is possible to safely use ticagrelor in a double or triple antithrombotic regimen containing DABE, only considering the antithrombotic efficacy, but not need to pay much attention on the pharmacokinetic DDI.

A 4-item PRECISE-DAPT score for dual antiplatelet therapy duration decision-making

The originally-proposed PRECISE-DAPT score is a 5-item risk score supporting decision-making for dual antiplatelet therapy¹ duration after PCI. It is unknown if a simplified version of the score based on 4 factors (age, hemoglobin, creatinine clearance, prior bleeding), and lacking white-blood cell count, retains potential to guide DAPT duration. The 4-item PRECISE-DAPT was used to categorize 10,081 patients who were randomized to short (3-6 months) or long (12-24 months) DAPT regimen according to high (HBR defined by PRECISE-DAPT ≥25 points) or non-high bleeding risk (PRECISE-DAPT<25) status. Long treatment duration was associated with higher bleeding rates in HBR (ARD +2.22% [95% CI +0.53 to +3.90]) but not in non-HBR patients (ARD +0.25% [-0.14 to +0.64]; p_int = 0.026), and associated with lower ischemic risks in non-HBR (ARD -1.44% [95% CI -2.56 to -0.31]), but not in HBR patients (ARD +1.16% [-1.91 to +4.22]; p_int = 0.11). Only non-HBR patients experienced lower net clinical adverse events (NACE) with longer DAPT (p_int = 0.043). A 4-item simplified version of the PRECISE-DAPT score retains the potential to categorize patients who benefit from prolonged DAPT without concomitant bleeding liability from those who do not.

Effect of Lesion Complexity and Clinical Risk Factors on the Efficacy and Safety of Dabigatran Dual Therapy Versus Warfarin Triple Therapy in Atrial Fibrillation After Percutaneous Coronary Intervention

Background:

The REDUAL PCI trial (Evaluation of Dual Therapy With Dabigatran vs Triple Therapy With Warfarin in Patients With AF That Undergo a PCI With Stenting) demonstrated that, in patients with atrial fibrillation following percutaneous coronary intervention, bleeding risk was lower with dabigatran plus clopidogrel or ticagrelor (dual therapy) than warfarin plus clopidogrel or ticagrelor and aspirin (triple therapy). Dual therapy was noninferior for risk of thromboembolic events. Whether these results apply equally to patients at higher risk of ischemic events due to lesion complexity or clinical risk factors is unclear.

Methods:

The primary end point was time to first major or clinically relevant nonmajor bleeding event. The composite efficacy end point was death, thromboembolic event, or unplanned revascularization. Our prespecified subgroup analysis categorized patients by presence of procedural complexity and/or clinical complexity factors at baseline. A modified dual antiplatelet therapy score categorized patients according to degree of clinical risk.

Results:

Of 2725 patients, 43.1% had clinical complexity factors alone, 9.9% procedural factors alone, 10.0% both, and 37.0% neither. Risk of the primary bleeding end point was lower in both dabigatran dual therapy groups than warfarin triple therapy groups, regardless of procedural and/or clinical lesion complexity (interaction P values: 0.90 and 0.37, respectively). Importantly, a similar risk of the efficacy end point was observed between dabigatran dual and warfarin triple therapy, regardless of the presence of clinical or procedural complexity factors (interaction P values: 0.67 and 0.54, dabigatran 110 and 150 mg dual therapy, respectively). Similar benefit was seen for each dose of dabigatran dual therapy for bleeding events regardless of dual antiplatelet therapy score (interaction P values: 0.53 and 0.54, respectively), with similar risk of thromboembolic events (interaction P values: 0.20 and 0.08, respectively).

Conclusions:

In patients with atrial fibrillation undergoing percutaneous coronary intervention, dabigatran 110 and 150 mg dual therapy reduced bleeding risk compared with warfarin triple therapy, with a similar risk of thromboembolic outcomes, irrespective of procedural and/or clinical complexity and modified dual antiplatelet therapy score.

Registration:

URL: https://clinicaltrials.gov/ ; Unique identifier: NCT02164864.

Comparison of the Effect of Age (< 75 Versus ≥ 75) on the Efficacy and Safety of Dual Therapy (Dabigatran + Clopidogrel or Ticagrelor) Versus Triple Therapy (Warfarin + Aspirin + Clopidogrel or Ticagrelor) in Patients With Atrial Fibrillation After Percutaneous Coronary Intervention (from the RE-DUAL PCI Trial)

The RE-DUAL PCI trial reported that dabigatran dual therapy (110/150 mg twice daily, plus clopidogrel or ticagrelor) reduced bleeding events versus warfarin triple therapy (warfarin plus aspirin and clopidogrel or ticagrelor) in patients with atrial fibrillation who underwent percutaneous coronary intervention, with noninferiority in composite thromboembolic events. In this prespecified analysis, risks of first major or clinically relevant nonmajor bleeding event and composite end point of death, thromboembolic events, or unplanned revascularization were compared between dabigatran dual therapy and warfarin triple therapy in older (≥ 75 years) and younger (< 75 years) patients, using Cox proportional hazard regression. Of 2,725 patients randomized to treatment, 1,026 (37.7%) were categorized into older and 1,699 (62.3%) into younger age groups. Dabigatran 110 mg dual therapy lowered bleeding risk versus warfarin triple therapy in older (hazard ratio [HR] 0.67; 95% confidence interval [CI] 0.51 to 0.89) and younger patients (HR 0.40; 95% CI 0.30 to 0.54); interaction p value: 0.0125. Dabigatran 150 mg dual therapy lowered bleeding risk versus warfarin triple therapy in younger patients (HR 0.57; 95% CI 0.44 to 0.74), whereas no benefit could be observed in older patients (HR 1.21; 95% CI 0.83 to 1.77); interaction p value: 0.0013. For the thromboembolic end point, there was a trend for a higher risk with dabigatran 110 mg dual therapy in older patients, compared with warfarin triple therapy, whereas the risk was similar in younger patients. For dabigatran 150 mg dual therapy, the thromboembolic risk versus warfarin triple therapy was similar in older and younger patients. In conclusion, the benefits of dabigatran dual therapy differed in the 2 age groups, which may help dose selection when using dabigatran dual therapy.

Direct-acting Anticoagulants in Chronic Coronary Syndromes

Direct-acting oral anticoagulants (DOACs) are easier to use, safer than and as effective as vitamin K antagonists (VKA) in the treatment of non-valvular AF (NVAF). Because of their favourable safety profile and easier use than VKAs, DOACs as anti-thrombotic therapy may have a role in the management of chronic coronary syndromes (CCS). To date, few studies have evaluated DOACs in this setting. Initial studies have focused on patients receiving DOACs for NVAF undergoing acute or elective percutaneous coronary intervention who additionally require dual antiplatelet therapy (DAPT). Rivaroxaban 15 mg once daily plus a P2Y₁₂ inhibitor compared with a VKA regimen was associated with a reduction of bleedings (HR 0.59; 95% CI [0.47–0.76]; p<0.001). Rivaroxaban 2.5 mg twice daily plus DAPT up to 12 months followed by rivaroxaban 15 mg once daily plus P2Y₁₂ inhibitor showed similar results. Dabigatran 110 mg twice daily plus a P2Y₁₂ inhibitor versus a VKA regimen was associated with a reduction of bleedings (HR 0.52; 95% CI [0.42–0.63]; p<0.001), after a mean follow-up of 14 months. A dabigatran 150 mg regimen showed similar results. Apixaban 5 mg twice daily plus a P2Y₁₂ inhibitor versus a VKA regimen confirmed at 6 months the safety of DOACs with a reduction of bleedings (HR 0.69; 95% CI [0.58–0.81]; p<0.001 for non-inferiority and superiority). Edoxaban 60 mg once daily plus a P2Y₁₂ inhibitor was non-inferior to a VKA regimen on bleeding outcomes (major bleeding or non-major clinically relevant non-major bleeding) after a 12-month follow-up (HR 0.83; 95% CI [0.65–1.05]; p=0.001 for non-inferiority; p=0.1154 for superiority). Meta-analysis of these four trials confirmed the safety of DOACs regarding bleeding outcomes, but showed a trend toward stent thrombosis for dual antithrombotic therapy using DOACs versus triple antithrombotic therapy using VKAs. DOACs may show promise in the management of high-risk patients with chronic coronary syndromes. In these patients, rivaroxaban 2.5 mg twice daily in addition to aspirin was shown to reduce the composite outcome of cardiovascular death, stroke or MI compared to aspirin alone (HR 0.76; 95% CI [0.66–0.86]; p<0.001). All-cause death, cardiovascular death and stroke were also significantly lower. This benefit was at the cost of an increase in non-fatal bleeding.

Non-vitamin K antagonist oral anticoagulants (NOACs) post-percutaneous coronary intervention: a network meta-analysis

BACKGROUND

Clinicians must balance the risks of bleeding and thrombosis after percutaneous coronary intervention (PCI) in people with an indication for anticoagulation. The potential of non-vitamin K antagonists (NOACs) to prevent bleeding complications is promising, but evidence remains limited.

OBJECTIVES

To review the evidence from randomised controlled trials assessing the efficacy and safety of non-vitamin K antagonist oral anticoagulants (NOACs) compared to vitamin K antagonists post-percutaneous coronary intervention (PCI) in people with an indication for anticoagulation.

SEARCH METHODS

We identified studies by searching CENTRAL, MEDLINE, Embase, the Conference Proceedings Citation Index - Science and two clinical trials registers in February 2019. We checked bibliographies of identified studies and applied no language restrictions.

SELECTION CRITERIA

We searched for randomised controlled trials (RCT) that compared NOACs and vitamin K antagonists for people with an indication for anticoagulation who underwent PCI.

DATA COLLECTION AND ANALYSIS

Two review authors independently checked the results of searches to identify relevant studies, assessed each included study, and extracted study data. We conducted random-effects, pairwise analyses using Review Manager 5 and network meta-analyses (NMA) using the R package 'netmeta'. We ranked competing treatments by P scores, which are derived from the P values of all pairwise comparisons, and allow ranking of treatments on a continuous 0 to 1 scale.

MAIN RESULTS

We identified nine RCTs that met the inclusion criteria, but four were ongoing trials, and were not included in this analysis. We included five RCTs, with 8373 participants, in the NMA (two RCTs compared apixaban to a vitamin K antagonist, two RCTs compared rivaroxaban to a vitamin K antagonist, and one RCT compared dabigatran to a vitamin K antagonist). Very low- to moderate-certainty evidence suggests little or no difference between NOACs and vitamin K antagonists in death from cardiovascular causes (not reported in the dabigatran trial), myocardial infarction, stroke, death from any cause, and stent thrombosis. Apixaban (RR 0.85, 95% CI 0.77 to 0.95), high dose rivaroxaban (RR 0.86, 95% CI 0.74 to 1.00), and low dose rivaroxaban (RR 0.80, 95% CI 0.68 to 0.92) probably reduce the risk of recurrent hospitalisation compared with vitamin K antagonists. No studies looked at health-related quality of life. Very low- to moderate-certainty evidence suggests that NOACs may be safer than vitamin K antagonists in terms of bleeding. Both high dose dabigatran (RR 0.53, 95% CI 0.29 to 0.97), and low dose dabigatran (RR 0.38, 95% CI 0.21 to 0.70) may reduce major bleeding more than vitamin K antagonists. High dose dabigatran (RR 0.83, 95% CI 0.72 to 0.96), low dose dabigatran (RR 0.66, 95% CI 0.58 to 0.75), apixaban (RR 0,67 , 95% Cl 0.51 to 0.88), high dose rivaroxaban (RR 0.66, 95% CI 0.52 to 0.83), and low dose rivaroxaban (RR 0.71, 95% CI 0.57 to 0.88) probably reduce non-major bleeding more than vitamin K antagonists. The results from the NMA were inconclusive between the different NOACs for all primary and secondary outcomes.

AUTHORS' CONCLUSIONS

Very low- to moderate-certainty evidence suggests no meaningful difference in efficacy outcomes between non-vitamin K antagonist oral anticoagulants (NOAC) and vitamin K antagonists following percutaneous coronary interventions (PCI) in people with non-valvular atrial fibrillation. NOACs probably reduce the risk of recurrent hospitalisation for adverse events compared with vitamin K antagonists. Low- to moderate-certainty evidence suggests that dabigatran may reduce the rates of major and non-major bleeding, and apixaban and rivaroxaban probably reduce the rates of non-major bleeding compared with vitamin K antagonists. Our network meta-analysis did not show superiority of one NOAC over another for any of the outcomes. Head to head trials, directly comparing NOACs against each other, are required to provide more certain evidence.

Warfarin therapy in Chinese patients with atrial fibrillation treated with percutaneous coronary intervention: a 5 year follow-up retrospective cohort study

Objective: To evaluate warfarin use in Chinese patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI) by investigating the stroke and major adverse cardiac and cerebral events (MACCEs) and bleeding events. Methods: Retrospective cohort study of the 5 year follow-up of 1134 patients with AF who underwent PCI. The patients were grouped according to whether they received warfarin or not. Baseline characteristics and the occurrence of MACCEs and bleeding events were compared between the two groups using the CHA2DS2-VASc and HAS-BLED scoring. Cox regression analysis was used to identify factors related to the occurrence of MACCEs and bleeding. Results: Overall MACCE (p = .008) and mortality (p = .004) rates were significantly lower in the warfarin group compared with the non-warfarin group. Major bleeding, minor bleeding and overall bleeding were comparable in the two groups. Recurrent myocardial infarction (HR = 10.129, 95% CI = 4.737-21.655; p < .001) and a baseline CHA2DS2-VASc score >4 (HR = 2.035, 95% CI = 1.121-3.692; p = .019) were independent predictors of MACCEs in the warfarin group. A baseline HAS-BLED score ≥3 (HR = 5.498, 95% CI = 3.773-8.013; p < .001) and previous bleeding (HR = 3.058, 95% CI = 1.319-7.088; p = .009) were independent predictors of bleeding. Conclusions: Warfarin reduces the incidence of MACCEs but does not increase bleeding events in Chinese patients with AF who underwent PCI. For patients taking warfarin, recurrent myocardial infarction and a baseline CHA2DS2-VASc score >4 were related to MACCE occurrence.

Development of New Antithrombotic Regimens for Patients with Acute Coronary Syndrome

Patients with acute coronary syndrome (ACS) require long-term antithrombotic intervention to reduce the risk of further ischemic events; dual antiplatelet therapy with a P2Y₁₂ inhibitor and acetylsalicylic acid (ASA) is the current standard of care. However, pivotal clinical trials report that patients receiving this treatment have a residual risk of approximately 10% for further ischemic events. The development of non-vitamin K antagonist oral anticoagulants (NOACs) has renewed interest in a 'dual pathway' strategy, targeting both the coagulation cascade and platelet component of thrombus formation. In the phase III ATLAS ACS 2 TIMI 51 trial, a 'triple therapy' approach (NOAC plus dual antiplatelet therapy) showed reduced ischemic events with rivaroxaban 2.5 mg twice daily, albeit at an increased risk of bleeding. Two studies have investigated the role of NOACs in combination with a P2Y₁₂ inhibitor, with or without ASA, in reducing bleeding risk in patients with atrial fibrillation undergoing percutaneous coronary intervention; two further studies are underway. Although these trials will help to inform optimal treatment protocols for secondary prevention of ACS, an individualized approach to treatment will be needed, taking account of the high frequency of co-morbid conditions found in this patient population.

Relationship of stroke and bleeding risk profiles to efficacy and safety of dabigatran dual therapy versus warfarin triple therapy in atrial fibrillation after percutaneous coronary intervention: An ancillary analysis from the RE-DUAL PCI trial

BACKGROUND

In the RE-DUAL PCI trial of patients with atrial fibrillation (AF) who underwent percutaneous coronary intervention (PCI), dabigatran dual therapy (110 or 150 mg bid, plus clopidogrel or ticagrelor) reduced International Society on Thrombosis and Haemostasis bleeding events compared with warfarin triple therapy, with noninferiority in overall thromboembolic events. This analysis assessed outcomes in relation to patient bleeding and stroke risk profiles, based on the modified HAS-BLED and CHA₂DS₂-VASc scores.

METHODS

The primary endpoint, major bleeding event (MBE) or clinically relevant nonmajor bleeding event (CRNMBE), was compared across study arms in patients categorized by modified HAS-BLED score 0-2 or ≥3. The composite endpoint of death, thromboembolic event, and unplanned revascularization rates was compared in patients categorized by CHA₂DS₂-VASc score 0-1, 2, or ≥3.

RESULTS

Risk of MBE or CRNMBE was lower with dabigatran dual therapy (both doses) versus warfarin triple therapy, irrespective of modified HAS-BLED category (treatment-by-subgroup interaction P-value 0.584 and 0.273 for dabigatran 110 and 150 mg dual therapy, respectively, vs warfarin). Risk of the composite thromboembolic endpoint was similar across CHA₂DS₂-VASc categories and consistent with overall study results (interaction P-value 0.739 and 0.075 for dabigatran 110 and 150 mg dual therapy, respectively, vs warfarin). Higher HAS-BLED scores were associated with higher risks of bleeding in AF patients after PCI in a treatment-independent analysis.

CONCLUSION

Dabigatran dual therapy reduced bleeding events irrespective of bleeding risk category and demonstrated similar efficacy regardless of stroke risk category when compared with warfarin triple therapy.

Dabigatran dual therapy with ticagrelor or clopidogrel after percutaneous coronary intervention in atrial fibrillation patients with or without acute coronary syndrome: a subgroup analysis from the RE-DUAL PCI trial

AIMS

After percutaneous coronary intervention (PCI) in patients with atrial fibrillation, safety and efficacy with dabigatran dual therapy were evaluated in pre-specified subgroups of patients undergoing PCI due to acute coronary syndrome (ACS) or elective PCI, and those receiving ticagrelor or clopidogrel treatment.

METHODS AND RESULTS

In the RE-DUAL PCI trial, 2725 patients were randomized to dabigatran 110 mg or 150 mg with P2Y12 inhibitor, or warfarin with P2Y12 inhibitor and aspirin. Mean follow-up was 14 months, 50.5% had ACS, and 12% received ticagrelor. The risk of the primary endpoint, major or clinically relevant non-major bleeding event, was reduced with both dabigatran dual therapies vs. warfarin triple therapy in patients with ACS [hazard ratio (95% confidence interval), 0.47 (0.35-0.63) for 110 mg and 0.67 (0.50-0.90) for 150 mg]; elective PCI [0.57 (0.43-0.76) for 110 mg and 0.76 (0.56-1.03) for 150 mg]; receiving ticagrelor [0.46 (0.28-0.76) for 110 mg and 0.59 (0.34-1.04) for 150 mg]; or clopidogrel [0.51 (0.41-0.64) for 110 mg and 0.73 (0.58-0.91) for 150 mg], all interaction P-values >0.10. Overall, dabigatran dual therapy was comparable to warfarin triple therapy for the composite endpoint of death, myocardial infarction, stroke, systemic embolism, or unplanned revascularization, with minor variations across the subgroups, all interaction P-values >0.10.

CONCLUSION

The benefits of both dabigatran 110 mg and 150 mg dual therapy compared with warfarin triple therapy in reducing bleeding risks were consistent across subgroups of patients with or without ACS, and patients treated with ticagrelor or clopidogrel.

The effect of ticagrelor based dual antiplatelet therapy on development of late left ventricular thrombus after acute anterior ST elevation myocardial infarction

AIM

The aim of this study is to investigate the impact of ticagrelor as compared to clopidogrel based dual antiplatelet therapy (DAPT) during post-discharge management on the incidence of left ventricular (LV) thrombus in patients with first acute anterior ST elevation myocardial infarction (STEMI).

METHOD

641 patients who met the inclusion criteria were divided into two groups based on the receipt of either ticagrelor or clopidogrel based DAPT.

RESULT

Left ventricular thrombus was detected in 73 (11.4%) patients at the first month echocardiographic examination. Ticagrelor based DAPT was associated with significantly less incidence of LV thrombus when compared to clopidogrel [20 (7.4%) vs 53 (14.0%) OR: 0.50 (0.29-0.86)]. Penalized maximum likelihood estimation (PMLE) logistic regression analyses were performed to fourteen candidate variables for identifying the independent predictors of LV thrombus, ticagrelor (compared with clopidogrel) [OR: 0.53 (0.28-0.96), p = 0.039], body mass index (BMI) [OR: 0.58 (0.44-0.77), p < 0.001], KILLIP class (I vs II-IV) [OR: 0.35 (0.14-0.83), p = 0.017], age [OR: 1.22 (1.08-1.40), p < 0.001], poor postprocedural myocardial blush grade (MBG) [OR: 3.35 (1.32-8.15), p = 0.012] and LVEF predischarge [OR: 0.79 (0.72-0.86), p < 0.001] were found to be associated with LV thrombus.

CONCLUSION

Our study demonstrated that the incidence of LV trombus was significantly lower with ticagrelor than clopidogrel-based DAPT during postdischarge treatment for anterior STEMI patients.

Usefulness of Antithrombotic Therapy in Patients With Atrial Fibrillation and Acute Myocardial Infarction

To examine patterns of preadmission and discharge antithrombotic therapies in coronary artery disease (CAD) and atrial fibrillation (AF) patients admitted for acute myocardial infarction (AMI), we performed a retrospective analysis of the Acute Coronary Treatment and Intervention Outcomes Network Registry-Get With the Guidelines (ACTION Registry-GWTG), which captures consecutive AMI patients treated at participating US hospitals. We included patients with CAD, AF, and CHA₂DS₂-VASc score ≥2 admitted for AMI (07/01/2013-09/30/2016). In the 15,034 AMI patients with previous AF and CAD, median age was 75; 32% were female. Preadmission, 32% of patients were on P2Y₁₂ inhibitors, 36% were anticoagulated, 72% were on aspirin, and 5% were on triple therapy. At discharge post-AMI, 73% were prescribed P2Y₁₂ inhibitors and 41% anticoagulation. Discharge anticoagulation use did not vary directly with CHA₂DS₂-VASc score; 16% of previously anticoagulated patients had discontinued anticoagulation at discharge. In patients receiving anticoagulants at discharge, 27% used nonvitamin K antagonist oral anticoagulants. Triple therapy was prescribed in 23% at discharge; 27% of these were with nonvitamin K antagonist oral anticoagulants and 14% with prasugrel or ticagrelor. P2Y₁₂ inhibitors and anticoagulants without aspirin were used in 2%. In conclusion, patients with previous CAD and AF are undertreated for both recurrent ischemic events and stroke prevention. After AMI hospitalization, P2Y₁₂ inhibition was preferentially selected over oral anticoagulation.

Management of Anticoagulation in Patients with Atrial Fibrillation Undergoing PCI: Double or Triple Therapy?

PURPOSE OF REVIEW

This review aims to discuss the use of antithrombotic therapy in patients with atrial fibrillation who undergo coronary stenting with emphasis on the use of double vs triple therapy.

RECENT FINDINGS

When combined with systemic anticoagulation, dual antiplatelet therapy results in an unacceptable increase in bleeding without any improvement in prevention of thrombotic events. Direct oral anticoagulants combined with single antiplatelet therapy have reduced bleeding compared with warfarin plus dual antiplatelet therapy. Triple anticoagulation therapy with warfarin or direct oral anticoagulants leads to an excess of bleeding and is not superior in preventing thrombotic events. Recent randomized, controlled trials have shown a significant reduction in major bleeding events in patients treated with dual antithrombotic therapy compared with triple therapy without any difference in efficacy. These findings call into question whether triple therapy should remain a part of standard practice.

Triple antithrombotic therapy in patients with atrial fibrillation undergoing PCI: current evidence and practice

INTRODUCTION

Patients with atrial fibrillation taking oral anticoagulation and undergoing percutaneous coronary intervention with stent insertion are recommended to receive antithrombotic therapy with aspirin and P2Y₁₂ receptor antagonist. This combinatory regime encompasses triple therapy (TT). Although TT reduces the risk of ischemic events such as stroke and stent thrombosis, it is associated with an increased bleeding risk. Areas covered: The efficacy and safety profile of TT is uncertain with undetermined optimal duration and therapeutic combination. This review summarizes relevant trials evaluating TTs application and introduces exploration of duration and dosage in addition to other contributory factors including stent type and choice of antithrombotic agents. Expert commentary: TT has shown to be effective for reduction of ischemic risk. However, trials have failed to demonstrate the regime's superiority in efficacy over alternatives such as dual therapy (single antiplatelet plus anticoagulant) and continue to denote an increased bleeding risk. Further research driven by a balance between thromboembolic and bleeding end points is required to demonstrate TTs potential beneficence, along with optimal duration identification and antithrombotic choice. Individualized patient risk stratification, along with risk factor optimization should also be incorporated.

Comparing Allergist and Cardiologist Considerations for the Optimal Management of Thienopyridines Hypersensitivity

BACKGROUND AND OBJECTIVE

The thienopyridine family includes ticlopidine, clopidogrel and prasugrel which are antiplatelet drugs largely used, mainly associated to aspirin, for treatment of acute coronary syndromes and after percutaneous coronary interventions, to avoid thrombosis. In some patients, thienpyridines may cause hypersensitivity reactions which jeopardize the optimal therapeutic and preventive approach to vascular diseases. The management of thienopyridine hypersensitivity seems to be best done as an interdisciplinary collaboration between the allergist and cardiologist.

METHOD

The present study investigates the management of thienopyridines hypersensitivity on the basis of published case reports and studies, comparing the pro and contro of pharmacological treatments, different desensitization protocols to thienopyridines and substitution of antiplatelet agents eaches others, according to the point of view of cardiologist and allergist. For the cardiologist, the important issues are the necessity of continuing therapy, the desired duration of therapy based on the clinical indication of the individual patient and appropriateness of using one of the alternative P2Y12 inhibitors. For the allergist, the important issues are weighing the risk and benefits of the various therapeutic options: treating "through" desensitization, or switching to an alternative agent.

RESULTS AND CONCLUSION

All the data seem to suggest that only working together, a cardio-allergy team of specialists may evaluate and offer the best approach to clinical decision-making for the individual patient.

Safety and efficacy of non-vitamin K oral anticoagulant for atrial fibrillation patients after percutaneous coronary intervention: A bivariate analysis of the PIONEER AF-PCI and RE-DUAL PCI trial

BACKGROUND

The tradeoff in safety versus efficacy in substituting a non-vitamin K antagonist oral anticoagulant for a vitamin K antagonist (VKA) in the stented atrial fibrillation patient has not been quantitatively evaluated.

METHODS

Based on summary data from the PIONEER AF-PCI and RE-DUAL PCI trials, 4 antithrombotic regimens were compared with VKA-based triple therapy: (1) rivaroxaban (riva) 15 mg daily + P2Y₁₂ inhibitor, (2) riva 2.5 mg twice daily + P2Y₁₂ inhibitor + aspirin, (3) dabigatran (dabi) 110 mg twice daily + P2Y₁₂ inhibitor, and (4) dabi 150 mg twice daily + P2Y₁₂ inhibitor. A bivariate model with a noninferiority margin of 1.38 was used to simultaneously assess safety and efficacy. The safety end point was major or clinically relevant nonmajor bleeding by International Society on Thrombosis and Haemostasis definitions. The efficacy end point was a thromboembolic event (myocardial infarction, stroke, or systemic embolism), death, or urgent revascularization. The bivariate outcome, a measure of risk difference in the net clinical outcome, was compared between antithrombotic regimens.

RESULTS

All 4 non-vitamin K antagonist oral anticoagulant regimens were superior in bleeding and noninferior in efficacy compared with triple therapy with VKA. Riva 15 mg daily and 2.5 mg twice daily were associated with bivariate combined risk reductions of 5.6% (2.3%-8.8%) and 5.5% (2.1%-8.7%), respectively, and dabi 110 mg twice daily and 150 mg twice daily reduced the bivariate risk by 3.8% (0.5%-7.0%) and 6.3% (2.4%-9.8%), respectively.

CONCLUSIONS

A bivariate analysis that simultaneously characterizes both risk and benefit demonstrates that riva- and dabi-based regimens were both favorable over VKA plus dual antiplatelet therapy among patients with atrial fibrillation undergoing PCI.

Effects of atrial fibrillation on complications and prognosis of patients receiving emergency PCI after acute myocardial infarction

The effects of atrial fibrillation on complications and prognosis of patients receiving emergency percutaneous coronary intervention after acute myocardial infarction (AMI) were investigated. Eighty AMI patients treated with interventional vascular recanalization in the Affiliated Hospital of Weifang Medical University (Weifang, China) from July 2015 to October 2016 were selected, including 40 patients complicated with atrial fibrillation before operation (control group) and 40 patients without atrial fibrillation before operation (observation group). The systolic blood pressure, diastolic blood pressure, heart rate, arrhythmia and common complications after MI were compared. Changes in the coronary artery thrombolysis in myocardial infarction (TIMI) flow grade and left ventricular ejection fraction (LVEF) of patients were also recorded. Moreover, changes in brain natriuretic peptide (BNP) levels were compared. The recovery time of myocardial enzyme and total troponin in both groups was recorded. The systolic and diastolic blood pressure in the observation group were significantly higher than those in the control group (p<0.05). During the intervention, the total proportion of patients with ventricular arrhythmia, atrial arrhythmia, atrioventricular block and sinus tachycardia in the observation group was significantly lower than that in the control group (p<0.05). The total proportion of common complications after MI in the observation group was obviously lower than that in the control group (p<0.05). Coronary artery TIMI flow grades and LVEFs in the observation group were obviously higher than those in the control group. BNP levels in the observation group were significantly lower than those in the control group. The recovery time of myocardial enzyme and total troponin in the observation group was significantly earlier than that in the control group. Atrial fibrillation has a certain negative effect on the circulatory function in patients with AMI after the interventional therapy, and the proportions of arrhythmia and complications in patients after MI are increased at the same time, so the postoperative recovery of patients is slow with many complications.

LMU Munich: platelet inhibition novel aspects on platelet inhibition and function

A core research area in the Department of Cardiology at Ludwig-Maximilians-University (LMU) Munich focuses on antiplatelet therapy, its translational aspects, and its underlying mechanism with respect to platelet physiology. We are conducting a broad range of investigator-initiated clinical trials (phase II-IV) and preclinical studies on the topic of antithrombotic therapy for percutaneous coronary intervention patients, platelet activation, and reactivity as well as on novel inhibitors of platelet adhesion. Just recently, we completed the large multi-centre investigator-initiated TROPICAL-ACS trial on guided early de-escalation of antiplatelet treatment in acute coronary syndrome (ACS) patients (Sibbing et al. in Lancet 390:1747-1757, 2017; Sibbing et al. in Thromb Haemost 117:1240-1248), done at 33 sites in Europe. Furthermore, besides other ongoing clinical studies, we initiated and are currently recruiting patients for the multi-centre randomized APixaban versus PhenpRocoumon in Patients With ACS and AF: APPROACH-ACS-AF study as well as for the multi-centre phase II randomized, double-blind, placebo-controlled study of revacept in Patients With Stable Coronary Artery Disease (Revacept/CAD/02) trial.

Comparative Review of Oral P2Y12 Inhibitors

Current practice guidelines recommend dual antiplatelet therapy comprised of aspirin and a purinergic signaling receptor Y₁₂ (P2Y₁₂) for patients following acute coronary syndrome. This article compares the efficacy, safety, and other characteristics of the three available oral P2Y₁₂ inhibitors-clopidogrel, prasugrel, and ticagrelor.

Optimum Antithrombotic Therapy in Patients Requiring Long-Term Anticoagulation and Undergoing Percutaneous Coronary Intervention

Management of patients on long-term anticoagulation requiring percutaneous coronary intervention is challenging. Triple therapy with oral anticoagulant and dual antiplatelet therapy is the standard of care. However, there is no strong evidence to support this strategy. There is emerging data regarding the safety and efficacy of dual therapy with oral anticoagulant and single antiplatelet therapy in these patients. In this comprehensive review we highlight available evidence regarding various antithrombotic regimens' efficacy and safety in patient with coronary artery disease undergoing percutaneous coronary intervention with long-term anticoagulation therapy requirements.

Safety and Efficacy of Triple Therapeutic Targets with Rivaroxaban after Acute Myocardial Infarction Complicated by Left Ventricular Thrombi in a Case of Nonvalvular Atrial Fibrillation

We present the complex case of a high-risk patient with nonvalvular atrial fibrillation, who experienced a non-ST elevation myocardial infarction complicated by left ventricular (LV) thrombi and underwent percutaneous coronary intervention with drug-eluting stent implantation. The patient was initially treated with short-term triple therapy including aspirin, clopidogrel, and rivaroxaban 15 mg/die. Following aspirin dropping one month after discharge, the patient continued on dual therapy with clopidogrel and rivaroxaban, and a clinical and imaging follow-up at 6 and 12 months confirmed the LV thrombi resolution, with no thromboembolic episodes and a good safety profile.

Role of rivaroxaban in the management of atrial fibrillation: insights from clinical practice

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, and it leads to significant morbidity and mortality, predominantly from ischemic stroke. Vitamin K antagonists, mainly warfarin, have been used for decades to prevent ischemic stroke in AF, but their use is limited due to interactions with food and other drugs, as well as the requirement for regular monitoring of the international normalized ratio. Rivaroxaban, a direct factor Xa inhibitor and the most commonly used non-vitamin K oral anticoagulant, avoids many of these challenges and is being prescribed with increasing frequency for stroke prevention in non-valvular AF. Randomized controlled trial (RCT) data from the ROCKET-AF(Rivaroxaban once daily oral direct Factor Xa inhibition compared with vitamin K antagonism for prevention of stroke and embolism trial in atrial fibrillation) trial have shown rivaroxaban to be non-inferior to warfarin in preventing ischemic stroke and systemic embolism and to have comparable overall bleeding rates. Applicability of the RCT data to real-world practice can sometimes be limited by complex clinical scenarios or multiple comorbidities not adequately represented in the trials. Available real-world evidence in non-valvular AF patients with comorbidities - including renal impairment, acute coronary syndrome, diabetes mellitus, malignancy, or old age - supports the use of rivaroxaban as safe and effective in preventing ischemic stroke in these subgroups, though with some important considerations required to reduce bleeding risk. Patient perspectives on rivaroxaban use are also considered. Real-world evidence indicates superior rates of drug adherence with rivaroxaban when compared with vitamin K antagonists and with alternative non-vitamin K oral anticoagulants - perhaps, in part, due to its once-daily dosing regimen. Furthermore, self-reported quality of life scores are highest among patients compliant with rivaroxaban therapy. The generally high levels of patient satisfaction with rivaroxaban therapy contribute to overall favorable clinical outcomes.

Use of oral anticoagulants in combination with antiplatelet(s) in atrial fibrillation

Objectives

To investigate temporal trends in the use of non-vitamin K oral anticoagulants (NOACs) and vitamin K antagonists (VKAs) in combination with aspirin and/or clopidogrel in patients with atrial fibrillation (AF) following acute myocardial infarction (MI) and/or percutaneous coronary intervention (PCI).

Methods

Using Danish nationwide registries, all patients with AF who survived 30 days after discharge from MI and/or PCI between 22 August 2011 and 30 September 2016 were identified.

Results

A total of 2946 patients were included in the study population, of whom 1967 (66.8%) patients were treated with VKA in combination with antiplatelet(s) (VKA+aspirin n=477, VKA+clopidogrel n=439, VKA+aspirin+clopidogrel n=1051) and 979 (33.2%) patients were treated with NOAC in combination with antiplatelet(s) (NOAC+aspirin n=252, NOAC+clopidogrel n=218, NOAC+aspirin+clopidogrel n=509). The overall study population had a median age of 76 years [IQR: 69–82] and consisted of 1995 (67.7%) men. Patients with MI as inclusion event accounted for 1613 patients (54.8%). Patients with high CHA2DS2-VASc score(congestive heart failure, hypertension, age ≥75 years (2 points), diabetes mellitus, history of stroke/transient ischemic attack/systemic thromboembolism (2 points), vascular disease, age 65-75 years, and female sex) accounted for 132 2814 (95.5%) of patients, and patients with high HAS-BLED score (hypertension, abnormal renal/liver function, history of stroke, history of bleeding, age >65 years, non-steroidal anti-inflammatory drug usages, or alcohol abuse, leaving out labile international normalized ratio (not available), and use of antiplatelets (exposure variable)) accounted for 934 (31.7%) of patients. There was an increase from 10% in 2011 to 52% in 2016 in the use of NOACs in combination with antiplatelet(s).

Conclusion

From 2011 to 2016, the use of NOAC in combination with antiplatelet(s) increased in patients with AF following MI/PCI and exceeded the use of VKA in combination with antiplatelet(s) by 2016.

Safety and Efficacy of Dual Versus Triple Antithrombotic Therapy in Patients Undergoing Percutaneous Coronary Intervention

BACKGROUND

Choosing an antithrombotic regimen after coronary intervention in patients with concomitant indication for anticoagulation is a challenge commonly encountered by clinicians.

METHODS

We performed a meta-analysis of observational studies and randomized, controlled trials comparing outcomes of triple therapy (dual antiplatelet therapy and anticoagulant) with dual therapy (single antiplatelet therapy and anticoagulant) in patients taking long-term anticoagulants after percutaneous coronary intervention. Major bleeding was the primary outcome. Random effects overall risk ratios (RRs) were calculated using the DerSimonian and Laird model.

RESULTS

Nine observational studies and 2 randomized controlled trials with a total of 7276 patients met our selection criteria. At a mean follow-up of 10.8 months major bleeding was higher in the triple therapy cohort compared with dual therapy (6.6% vs 3.8%; RR 1.54; 95% confidence interval [CI], 1.2-1.98; P <.01). No difference was observed between the 2 groups for all-cause mortality (RR 0.98; 95% CI, 0.68-1.43; P = .93), major adverse cardiac events (RR 1.03; 95% CI, 0.8-1.32; P = .83), thromboembolic events (RR 1.02; 95% CI, 0.49-2.10; P = .96), myocardial infarction (RR 0.85; 95% CI, 0.67-1.09; P = .21), stent thrombosis (RR 0.77; 95% CI, 0.46-1.3; P = .33), and target vessel revascularization (RR 0.87; 95% CI, 0.66-1.15; P = .33).

CONCLUSION

In patients receiving anticoagulant therapy, a strategy of single antiplatelet therapy confers a benefit of less major bleeding with no difference in all-cause mortality, cardiovascular mortality, major adverse cardiac events, myocardial infarction, stent thrombosis, or thromboembolic event rate compared with dual antiplatelet therapy.

Dual Antithrombotic Therapy with Dabigatran after PCI in Atrial Fibrillation

BACKGROUND

Triple antithrombotic therapy with warfarin plus two antiplatelet agents is the standard of care after percutaneous coronary intervention (PCI) for patients with atrial fibrillation, but this therapy is associated with a high risk of bleeding.

METHODS

In this multicenter trial, we randomly assigned 2725 patients with atrial fibrillation who had undergone PCI to triple therapy with warfarin plus a P2Y₁₂ inhibitor (clopidogrel or ticagrelor) and aspirin (for 1 to 3 months) (triple-therapy group) or dual therapy with dabigatran (110 mg or 150 mg twice daily) plus a P2Y₁₂ inhibitor (clopidogrel or ticagrelor) and no aspirin (110-mg and 150-mg dual-therapy groups). Outside the United States, elderly patients (≥80 years of age; ≥70 years of age in Japan) were randomly assigned to the 110-mg dual-therapy group or the triple-therapy group. The primary end point was a major or clinically relevant nonmajor bleeding event during follow-up (mean follow-up, 14 months). The trial also tested for the noninferiority of dual therapy with dabigatran (both doses combined) to triple therapy with warfarin with respect to the incidence of a composite efficacy end point of thromboembolic events (myocardial infarction, stroke, or systemic embolism), death, or unplanned revascularization.

RESULTS

The incidence of the primary end point was 15.4% in the 110-mg dual-therapy group as compared with 26.9% in the triple-therapy group (hazard ratio, 0.52; 95% confidence interval [CI], 0.42 to 0.63; P<0.001 for noninferiority; P<0.001 for superiority) and 20.2% in the 150-mg dual-therapy group as compared with 25.7% in the corresponding triple-therapy group, which did not include elderly patients outside the United States (hazard ratio, 0.72; 95% CI, 0.58 to 0.88; P<0.001 for noninferiority). The incidence of the composite efficacy end point was 13.7% in the two dual-therapy groups combined as compared with 13.4% in the triple-therapy group (hazard ratio, 1.04; 95% CI, 0.84 to 1.29; P=0.005 for noninferiority). The rate of serious adverse events did not differ significantly among the groups.

CONCLUSIONS

Among patients with atrial fibrillation who had undergone PCI, the risk of bleeding was lower among those who received dual therapy with dabigatran and a P2Y₁₂ inhibitor than among those who received triple therapy with warfarin, a P2Y₁₂ inhibitor, and aspirin. Dual therapy was noninferior to triple therapy with respect to the risk of thromboembolic events. (Funded by Boehringer Ingelheim; RE-DUAL PCI ClinicalTrials.gov number, NCT02164864 .).

Atrial fibrillation, bleeding, and coronary intervention: current recommendations

The patient population with the need for oral anticoagulation to reduce stroke risk associated with atrial fibrillation (AF) and dual antiplatelet therapy to prevent stent thrombosis and myocardial infarction after percutaneous coronary intervention is increasing. However, patients treated with a triple therapy consisting of oral anticoagulation, aspirin, and a P2Y12 inhibitor have been demonstrated to be at high bleeding risk. The best combination of these agents and the duration of the different therapies are still uncertain. Recently, data on the safety of combinations including nonvitamin K antagonists have been published and evidence for the feasibility of a dual therapy is increasing. This review aims to provide insights to the pathophysiology of thrombus formation in AF versus coronary artery disease, summarize available data on postprocedural treatment strategies, and report current guidelines for AF patients after percutaneous coronary intervention. Furthermore, the role of stent type selection and tools to evaluate as well as strategies to reduce the individual bleeding risk will be discussed.

Efficacy and safety of triple versus dual antithrombotic therapy in atrial fibrillation and ischemic heart disease: a systematic review and meta-analysis

The optimal antithrombotic regimen for patients with atrial fibrillation and ischemic heart disease remains unclear. Therefore, we aimed to compare the efficacy and safety of triple therapy (TT [an anticoagulant and 2 antiplatelet drugs]) with dual therapy (DAPT [2 antiplatelet drugs] or DT [an anticoagulant and a single antiplatelet drug]) in patients with atrial fibrillation and ischemic heart disease. We systematically searched the Cochrane Library, PubMed and Embase databases for all relevant studies up to August 2017. The overall risk estimates were calculated using the random-effects model. A total of 17 observational studies were included. Regarding the efficacy outcomes, no differences were observed between the triple therapy and the dual therapy for all-cause death, cardiovascular death, or thrombotic complications (i.e., acute coronary syndrome, stent thrombosis, thromboembolism/stroke, and major adverse cardiac and cerebrovascular events). Regarding the safety outcomes, compared with DAPT, TT was associated with increased risks of major bleeding (a relative risk of 1.96 [1.40–2.74]), minor bleeding (1.69 [1.06–2.71]) and overall bleeding (1.80 [1.23–2.64]). Compared wtih DT, TT was associated with a greater risk of major bleeding (1.65 [1.23–2.21]), but rates of minor bleeding (0.99 [0.56–1.77]) and overall bleeding (1.14 [0.76–1.71]) were similar. Overall, TT confers an increased hazard of major bleeding with no thromboembolic protection compared with dual therapy in patients with atrial fibrillation and ischemic heart disease.

Anticoagulation after coronary stenting: a systemic review

Introduction or background

Anticoagulant therapy is mainly used to prevent patients from suffering coronary and systemic thromboembolism after stenting. Many studies have been done to formulate an optimized regimen of a post-PCI or long-time anticoagulant therapy. Recent advances in the selection and duration of anticoagulant agents will be conducive to the management of patients who are considered to need anticoagulant therapy after stenting.

Sources of data

Key recent published literature, including international guidelines and relevant reviews.

Areas of agreement

Anticoagulant therapy has been acknowledged to improve the prognosis of patients after stenting by reducing the risk of coronary and systemic thromboembolism.

Areas of controversy

Firstly, the benefit-risk ratio of post-PCI parenteral anticoagulation to prevent stent thrombosis locally in the coronary artery is still unclear. Secondly, the efficacy and safety of bivalirudin deserve to be discussed. Furthermore, the recommendation to use long-time oral anticoagulant therapy to prevent systemic thromboembolism after stenting should also be emphasized.

Growing points

Studies of anticoagulant therapy in patients after stenting add to the understanding of an optimized anticoagulant regimen and contribute to improving clinical outcomes.

Areas for developing research

The safety and efficacy of bivalirudin, a direct thrombin inhibitor, need to be further investigated by more large-scale randomized clinical trials.Based on the widespread use of ticagrelor and prasugrel for patients who need long-time oral anticoagulant therapy, further study is needed to find an optimal strategy that balances the risk of bleeding and ischemic events after coronary stenting.