Renal Function and Outcomes With Dabigatran Dual Antithrombotic Therapy in Atrial Fibrillation Patients After PCI

Antithrombotic Management in AF Patients Following Percutaneous Coronary Intervention: A European Perspective

AF is a highly prevalent disease, often requiring long-term oral anticoagulation to prevent stroke or systemic embolism. Coronary artery disease, which is common among AF patients, is often referred for myocardial revascularisation by percutaneous coronary intervention (PCI), which requires dual antiplatelet therapy to minimise the risk of stent-related complications. The overlap of AF and PCI is a clinical conundrum, especially in the early post-procedural period, when both long-term oral anticoagulation and dual antiplatelet therapy are theoretically indicated as a triple antithrombotic therapy. However, stacking drugs is not a desirable option because of the increased bleeding risk. Several strategies have been investigated to mitigate this concern, including shortening triple antithrombotic therapy duration and switching to a dual antithrombotic regimen. This review analyses the mechanisms underlying thrombotic complications in AF-PCI, summarises evidence surrounding antithrombotic therapy regimens and reports and comments on the latest European guidelines.

Optimizing the Outcomes of Percutaneous Coronary Intervention in Patients with Chronic Kidney Disease

Percutaneous coronary intervention (PCI) is one of the most common procedures performed in medicine. However, its net benefit among patients with chronic kidney disease (CKD) is less well established than in the general population. The prevalence of patients suffering from both CAD and CKD is high, and is likely to increase in the coming years. Planning the adequate management of this group of patients is crucial to improve their outcome after PCI. This starts with proper preparation before the procedure, the use of all available means to reduce contrast during the procedure, and the implementation of modern strategies such as radial access and drug-eluting stents. At the end of the procedure, personalized antithrombotic therapy for the patient’s specific characteristics is advisable to account for the elevated ischemic and bleeding risk of these patients.

The role of triple antithrombotic therapy in patients with atrial fibrillation undergoing percutaneous coronary intervention

Dual antiplatelet therapy (DAPT) with aspirin plus clopidogrel forms the backbone of secondary prevention in patients with acute coronary syndromes (ACS) or who undergo percutaneous coronary intervention (PCI), but in patients with atrial fibrillation (AF), oral anticoagulation (OAC) is superior to antiplatelet therapy for the prevention of stroke and systemic embolism. Patients with AF who undergo PCI or have an ACS event therefore have an indication for both OAC and DAPT, so-called triple antithrombotic therapy. However, observational analyses have shown that the annual rate of major bleeding on triple therapy exceeds 10%. For this reason, five major randomized clinical trials have compared double antithrombotic therapy with OAC and a P2Y₁₂ inhibitor versus triple therapy in patients with AF who underwent PCI or had an ACS event. Each of the trials showed that double antithrombotic therapy reduced the rate of major and clinically relevant non-major bleeding compared with triple therapy and was non-inferior for prevention of ischemic events, including cardiovascular death, myocardial infarction, or stroke. In the one trial that directly compared warfarin with a non-vitamin K antagonist oral anticoagulant (NOAC), apixaban reduced the rate of major or clinically relevant non-major bleeding compared with warfarin and was non-inferior with respect to prevention of ischemic events. As a result of these trials, consensus guidelines recommend that patients with AF who undergo PCI or have an ACS event should be treated with triple antithrombotic therapy (OAC + P2Y₁₂ inhibitor + aspirin) for 7 days or less, followed by double antithrombotic therapy (OAC + P2Y₁₂ inhibitor) for 6 to 12 months.

Impact of Renal Function on Effectiveness and Safety Associated With Low Dose Dabigatran in Non-valve Atrial Fibrillation Patients After Catheter Ablation

Aim: The purpose of this study is to compare the effectiveness and safety of 110 mg dabigatran in non-valve atrial fibrillation (NVAF) patients with different eGFRs.

Methods: We conducted a single-center retrospective cohort study to investigate the effectiveness and safety of 110 mg dabigatran for NVAF patients between January 2017 and December 2018 based on the eGFR category.

Results: A total of 560 NVAF patients who treated with 110 mg dabigatran were included for analysis. In 12 months, the Kaplan-Meier survival curves indicated that the lower eGFR subgroups were more likely to experience thrombosis, bleeding, and cumulative events earlier (P = 0.021 for thrombosis; P = 0.026 for bleeding; P = 0.001 for cumulative events). Gastrointestinal bleeding occurred more frequently in the moderate group than in other groups (6.94% in the moderate group vs. 1.54% in the mild group vs. 1.22% in the normal group, P = 0.028). By multivariate analysis, chronic kidney disease (P = 0.043; OR = 4.273, 95% CI 1.043–17.543) and diabetes mellitus (P = 0.023; OR = 2.194, 95% CI 1.114–4.323) were independent predictors of the composite endpoints. A positive linear relationship was observed between eGFR levels and occurrence rate of thrombosis and bleeding under anticoagulation patients with 110 mg dabigatran (R² = 0.432 and R² = 0.784, respectively).

Conclusions: Impaired renal function was associated with decreased safety and increased thrombosis risks in NVAF patients taking low dose dabigatran.

Apixaban or Vitamin K Antagonists and Aspirin or Placebo According to Kidney Function in Patients With Atrial Fibrillation After Acute Coronary Syndrome or Percutaneous Coronary Intervention: Insights From the AUGUSTUS Trial

BACKGROUND

In the AUGUSTUS trial (An Open-Label, 2×2 Factorial, Randomized Controlled, Clinical Trial to Evaluate the Safety of Apixaban Versus Vitamin K Antagonist and Aspirin Versus Aspirin Placebo in Patients With Atrial Fibrillation and Acute Coronary Syndrome or Percutaneous Coronary Intervention), apixaban resulted in less bleeding and fewer hospitalizations than vitamin K antagonists, and aspirin caused more bleeding than placebo in patients with atrial fibrillation and acute coronary syndrome or percutaneous coronary intervention treated with a P2Y₁₂ inhibitor. We evaluated the risk-benefit balance of antithrombotic therapy according to kidney function.

METHODS

In 4456 patients, the CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) formula was used to calculate baseline estimated glomerular filtration rate (eGFR). The effect of apixaban versus vitamin K antagonists and aspirin versus placebo was assessed across kidney function categories by using Cox models. The primary outcome was International Society on Thrombosis and Haemostasis major or clinically relevant nonmajor bleeding. Secondary outcomes included death or hospitalization and ischemic events (death, stroke, myocardial infarction, stent thrombosis [definite or probable], or urgent revascularization). Creatinine clearance <30 mL/min was an exclusion criterion in the AUGUSTUS trial.

RESULTS

Overall, 30%, 52%, and 19% had an eGFR of >80, >50 to 80, and 30 to 50 mL·min^-1·1.73 m^-2, respectively. At the 6-month follow-up, a total of 543 primary outcomes of bleeding, 1125 death or hospitalizations, and 282 ischemic events occurred. Compared with vitamin K antagonists, patients assigned apixaban had lower rates for all 3 outcomes across most eGFR categories without significant interaction. The absolute risk reduction with apixaban was most pronounced in those with an eGFR of 30 to 50 mL·min^-1·1.73 m^-2 for bleeding events with rates of 13.1% versus 21.3% (hazard ratio, 0.59; 95% CI, 0.41-0.84). Patients assigned aspirin had a higher risk of bleeding in all eGFR categories with an even greater increase among those with eGFR >80 mL·min^-1·1.73 m^-2: 16.6% versus 5.6% (hazard ratio, 3.22; 95% CI, 2.19-4.74; P for interaction=0.007). The risk of death or hospitalization and ischemic events were comparable to aspirin and placebo across eGFR categories with hazard ratios ranging from 0.97 (95% CI, 0.76-1.23) to 1.28 (95% CI, 1.02-1.59) and from 0.75 (95% CI, 0.48-1.17) to 1.34 (95% CI, 0.81-2.22), respectively.

CONCLUSIONS

The safety and efficacy of apixaban was consistent irrespective of kidney function, compared with warfarin, and in accordance with the overall trial results. The risk of bleeding with aspirin was consistently higher across all kidney function categories. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02415400.

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.