Demystifying the Contemporary Role of 12-Month Dual Antiplatelet Therapy After Acute Coronary Syndrome.

For almost two decades, 12-month dual antiplatelet therapy (DAPT) in acute coronary syndrome (ACS) has been the only class I recommendation on DAPT in American and European guidelines, which has resulted in 12-month durations of DAPT therapy being the most frequently implemented in ACS patients undergoing percutaneous coronary intervention (PCI) across the globe. Twelve-month DAPT was initially grounded in the results of the CURE (Clopidogrel in Unstable Angina to Prevent Recurrent Events) trial, which, by design, studied DAPT versus no DAPT rather than the optimal DAPT duration. The average DAPT duration in this study was 9 months, not 12 months. Subsequent ACS studies, which were not designed to assess DAPT duration, rather its composition (aspirin with prasugrel or ticagrelor compared with clopidogrel) were further interpreted as supportive evidence for 12-month DAPT duration. In these studies, the median DAPT duration was 9 or 15 months for ticagrelor and prasugrel, respectively. Several subsequent studies questioned the 12-month regimen and suggested that DAPT duration should either be fewer than 12 months in patients at high bleeding risk or more than 12 months in patients at high ischemic risk who can safely tolerate the treatment. Bleeding, rather than ischemic risk assessment, has emerged as a treatment modifier for maximizing the net clinical benefit of DAPT, due to excessive bleeding and no clear benefit of prolonged treatment regimens in high bleeding risk patients. Multiple DAPT de-escalation treatment strategies, including switching from prasugrel or ticagrelor to clopidogrel, reducing the dose of prasugrel or ticagrelor, and shortening DAPT duration while maintaining monotherapy with ticagrelor, have been consistently shown to reduce bleeding without increasing fatal or nonfatal cardiovascular or cerebral ischemic risks compared with 12-month DAPT. However, 12-month DAPT remains the only class-I DAPT recommendation for patients with ACS despite the lack of prospectively established evidence, leading to unnecessary and potentially harmful overtreatment in many patients. It is time for clinical practice and guideline recommendations to be updated to reflect the totality of the evidence regarding the optimal DAPT duration in ACS.

De-escalation of antithrombotic treatment after acute coronary syndrome, a new paradigm.

After an acute coronary syndrome (ACS) it is imperative to balance the bleeding vs. the ischemic risk given the similar prognostic impact of the two events. Since the post-discharge bleeding risk is substantially stable over time whereas the ischemic risk accumulates in the first weeks to months, a strategy of de-escalation of antithrombotic treatment, consisting in the reduction of either the duration (i.e., early interruption of one antiplatelet agent) or the intensity (i.e., switching from the more potent P2Y12-inhibitors prasugrel or ticagrelor to clopidogrel) of dual antiplatelet therapy (DAPT), has been proposed. Reducing the intensity of DAPT can be carried out as a default strategy (unguided approach) or based on the results of either platelet function tests or genetic tests (guided approach). Overall, all de-escalation strategies have shown to consistently decrease bleeding events with no apparent increase in ischemic events as compared to 12-month standard-of-care DAPT. Owing however to several limitations and weaknesses of the available evidence, de-escalation strategies are currently not recommended as a routine, but should rather be considered for selected ACS patients, such as those at increased risk of bleeding.

Needs-based considerations for the role of low-dose aspirin along the CV risk continuum.

Cardiovascular disease (CVD) remains the leading cause of death worldwide. The risk of a cardiovascular (CV) event is not static and increases along a continuum, making identification and management complex. Aspirin has been the cornerstone of antiplatelet therapy in CV risk reduction and remains the only antiplatelet agent with current guideline recommendations throughout the CV risk continuum. In light of recent trials, the role of aspirin in CVD prevention in asymptomatic patients has been downgraded in clinical guidelines. However, a substantial proportion of asymptomatic patients have underlying conditions, such as advanced subclinical atherosclerosis that are associated with high CV risk. Advanced subclinical atherosclerosis has not been extensively investigated in patients in clinical trials but in the absence of significant bleeding risks, patients with subclinical atherosclerosis may particularly benefit from preventive aspirin therapy. Recent studies and clinical guidelines support the need for a personalized treatment approach for these patients, balancing their risk of future CV events against their relative bleeding risk. In this commentary, we first discussed various tools and strategies currently available for assessing CV and bleeding risks; we then provided two hypothetical cases to outline how these tools can be implemented for optimal management of patients with no prior CV events who, nonetheless, are susceptible to CVD. The first case details a young and apparently healthy patient with underlying advanced subclinical atherosclerosis; whereas the second case describes a patient with recently diagnosed type 2 diabetes mellitus who is at higher risk of CVD than their non-diabetic counterparts. For both cases, we considered patient clinical characteristics, CV and bleeding risks, as well as other risk factors to evaluate the appropriate treatment strategy and determine whether patients would obtain a net clinical benefit from low-dose aspirin therapy. These cases can serve as examples to guide clinical decision-making on the use of low-dose aspirin for primary CVD prevention and improve CVD management via a personalized approach.

Dual-pathway Inhibition with Low-dose Aspirin and Rivaroxaban versus Aspirin Monotherapy in Patients with Coronary Artery Disease and Peripheral Artery Disease: Systematic Literature Review and Meta-analysis.

Background: Low-dose aspirin lowers cardiovascular event risk; dual-pathway inhibition (DPI) using low-dose aspirin with low-dose rivaroxaban may reduce this risk further. A systematic literature review and meta-analysis compared the efficacy, safety and net clinical benefit (NCB) of DPI with aspirin. Methods: PubMed and Embase were searched for randomised controlled trials reporting clinical efficacy, safety and NCB of DPI compared with aspirin alone in patients with coronary artery disease (CAD) and/or peripheral artery disease. Six articles representing four trials were included. Results: DPI versus aspirin alone significantly reduced major adverse cardiovascular events (HR 0.77; 95% CI [0.69-0.87]; p<0.01), increased International Society on Thrombosis and Haemostasis major bleeding events (HR 1.67; 95% CI [1.37-2.02]; p<0.01) and resulted in a significant NCB (HR 0.79; 95% CI [0.70-0.90]; p<0.01). Conclusion: These results underscore the potential benefit of DPI in patients with CAD, including those in the immediate post-acute coronary syndrome stage and with established CAD, as well as patients with peripheral artery disease.

Incidence and pattern of urgent revascularization in acute coronary syndromes treated with ticagrelor or prasugrel.

BACKGROUND: The ISAR-REACT 5 trial compared the efficacy and safety of ticagrelor and prasugrel in patients with ACS managed invasively. The present study sought to investigate the impact of ticagrelor and prasugrel on the incidence and pattern of urgent revascularization in acute coronary syndromes (ACS) patients undergoing percutaneous coronary intervention (PCI). METHODS AND RESULTS: This post-hoc analysis of the ISAR-REACT 5 trial included all ACS patients who underwent PCI. The primary endpoint for this analysis was the incidence of urgent revascularization at 12-month follow-up. Secondary outcome was the pattern of urgent revascularization procedures (namely, urgent target vessel/non-target vessel revascularization - TVR/NTVR). Among 3,377 ACS patients who underwent PCI, 1,676 were assigned to ticagrelor and 1,701 to prasugrel before PCI. After 12 months, the incidence of urgent revascularization was higher among patients assigned to ticagrelor as compared to prasugrel (6.8% vs. 5.2%; hazard ratio [HR] = 1.32, 95% confidence interval [CI] 1.00-1.75; p = 0.051), mostly attributable to significantly more urgent NTVR in the ticagrelor group (3.8% vs. 2.4%; HR = 1.62 [1.09-2.41]; p = 0.017). The risk of urgent TVR did not differ between treatment groups (3.3% vs. 3.0%; HR = 1.13 [0.77-1.65]; p = 0.546). CONCLUSIONS: In ACS patients treated with PCI, the cumulative rate of urgent revascularizations after 12 months is higher with ticagrelor compared to prasugrel, due to a significant increase in urgent revascularizations involving remote coronary vessels.