1-Year Outcomes of Patients Undergoing Primary Angioplasty for Myocardial Infarction Treated With Prasugrel Versus Ticagrelor

Prasugrel Versus Ticagrelor in Patients with Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention: a Systematic Review and Meta-analysis of Randomized Trials

PURPOSE

Dual antiplatelet therapy (DAPT) with aspirin and ticagrelor or prasugrel is the mainstay of treatment for patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI). We aimed to systematically perform a head-to-head comparison of ticagrelor vs prasugrel in terms of efficacy and safety.

METHODS

We searched PubMed/Medline, EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL) for relevant published randomized controlled trials (RCTs). The primary outcome was adverse cardiovascular events and secondary outcome was bleeding events. A random-effects meta-analysis was used to obtain the pooled estimate of each outcome.

RESULTS

Nine RCTs with a total number of 6990 patients (3550 treated with prasugrel and 3481 treated with ticagrelor) were included. No significant difference between prasugrel and ticagrelor was observed in terms of mortality (OR 0.86, 95% CI 0.66 to 1.13, P = 0.28), major adverse cardiovascular events (MACEs) (OR 0.85, 95% CI 0.70 to 1.03, P = 0.10), non-fatal myocardial infarction (OR 0.78, 95% CI 0.57 to 1.06, P = 0.11), stroke (OR 1.02, 95% CI 0.60 to 1.72, P = 0.95), stent thrombosis (OR 0.76, 95% CI 0.47 to 1.21, P = 0.25), thrombolysis in myocardial infarction (TIMI) defined major (OR 0.94, 95% CI 0.19 to 4.67, P = 0.94), minor (OR 0.35, 95% CI 0.08 to 1.62, P = 0.18) and minimal (OR 0.48, 95% CI 0.19 to 1.18, P = 0.11) bleeding and Bleeding Academic Research Consortium (BARC) defined bleeding (OR 1.06, 95% CI 0.82 to 1.36, P = 0.68).

CONCLUSION

In patients with ACS undergoing PCI, both prasugrel and ticagrelor were associated with similar cardiovascular outcomes and adverse bleeding events.

Risk Stratification after an Acute Coronary Syndrome: Significance of Antithrombotic Therapy

The impact of the de-escalation strategy of antiplatelet therapy (APT) on the life expectancy after acute coronary syndromes (ACS) and percutaneous coronary intervention (PCI) requires an assessment in real clinical practice. Into the Russian multicentral observational trial (ORACLE II ClinicalTrials.gov number, NCT04068909), 1803 patients with ACS and PCI indications were enrolled. During 12 months of follow-up, 228 all-cause deaths have occurred. The analysis of death predictors was carried out by the classification tree method. Age, an option of antithrombotic therapy, a history of chronic heart failure, and uric acid level had the greatest prognostic value. The death prediction model's sensitivity was 82.1% in the training cohort and 79.2% in the test cohort. During the observation period, ticagrelor was replaced with clopidogrel (APT de-escalation) in 357 patients. The groups of patients with different antiplatelet therapy options were adjusted for clinical parameters by the pseudorandomization method. The de-escalation group had the lowerest all-cause death rate. The incidence of bleeding and recurrent nonfatal coronary events in the study groups did not differ significantly. Thus, the APT regimen's advantage of changing from the maximum in the first weeks after ACS to moderate at follow-up has been confirmed. There is an obvious need to study the possibilities of individualizing antiplatelet therapy in patients after acute coronary syndromes.

Antithrombotic treatment in primary percutaneous coronary intervention

INTRODUCTION

Despite a timely mechanical reperfusion with primary percutaneous coronary intervention (pPCI) patients presenting with ST-elevation myocardial infarction (STEMI) display an increased risk of adverse cardiovascular events. Several studies have demonstrated that guideline-directed antithrombotic therapy is effective to reduce this risk. However, there is still much to be accomplished to improve antithrombotic therapies in this clinical setting.

AREAS COVERED

This paper reviews current data on antithrombotic therapy in STEMI patients undergoing pPCI.

EXPERT OPINION

Antithrombotic therapy for STEMI patients undergoing pPCI should take into account the variability of thrombotic and bleeding risk in the short and long term. Patients with STEMI profit from the administration of early onset antiplatelet agents and anticoagulation to achieve sufficient and predictable antithrombotic effect at the time of pPCI. Thereafter, antithrombotic therapies should be tailored to individual risk of recurrence over the long term, to avoid excess bleeding, while ensuring adequate secondary ischemic prevention.

Modern Antiplatelet Therapy for Percutaneous Coronary Intervention. How to Make the Right Choice?

Dual antiplatelet therapy is the most important step in acute coronary syndrome (ACS) treatment. The new generation of inhibitors of P2Y12 platelet receptors (prasugrel and ticagrelor) provide more pronounced platelet inhibition than clopidogrel. The drugs differ in pharmacodynamics and platelet reactivity tests due to different mechanisms of binding to P2Y12 receptors. The antiplatelet effect of prasugrel and ticagrelor provides clinical benefit and better prognosis in patients with various forms of ACS. In patients with ST-segment elevation ACS prasugrel and ticagrelor are preferred over clopi-dogrel due to their higher efficacy and better clinical outcomes, and currently have preferential positions in guidelines compared to clopidogrel. The comparison of prasugrel versus ticagrelor (ISAR-REACT 5 trial) demonstrated superiority of prasugrel over ticagrelor in patients with ST-segment elevation ACS, for whom an invasive evaluation is planned and in early invasive treatment non-ST-segment elevation ACS. The choice of a drug for dual antiplatelet therapy in various clinical situations remains controversial. The latest ESC guidelines on non-ST elevation ACS (2020) [1] demonstrate the possible preference for prasugrel in patients with ACS without ST-segment elevation undergoing percutaneous coronary intervention. Current article demonstrates the results of recent clinical studies and the real clinical data regarding antiplatelet therapy in patients with coronary interventions. The indications for the use of P2Y12 platelet inhibitors in certain groups of patients are outlined. Treatment selection of the most effective and safe drugs in patients with ACS is highlighted according to the updated European guidelines.

Ticagrelor or Prasugrel in Patients With ST-Segment–Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention

Background:

Data on the comparative efficacy and safety of ticagrelor versus prasugrel in patients with ST-segment–elevation myocardial infarction undergoing primary percutaneous coronary intervention are limited. We assessed the efficacy and safety of ticagrelor versus prasugrel in a head-to-head comparison in patients with ST-segment–elevation myocardial infarction undergoing primary percutaneous coronary intervention.

Methods:

In this prespecified subgroup analysis, we included 1653 patients with ST-segment–elevation myocardial infarction randomized to receive ticagrelor or prasugrel in the setting of the ISAR REACT-5 trial (Intracoronary Stenting and Antithrombotic Regimen: Rapid Early Action for Coronary Treatment 5). The primary end point was the incidence of death, myocardial infarction, or stroke at 1 year after randomization. The secondary end point was the incidence of bleeding defined as BARC (Bleeding Academic Research Consortium) type 3 to 5 bleeding at 1 year after randomization.

Results:

The primary end point occurred in 83 patients (10.1%) in the ticagrelor group and in 64 patients (7.9%) in the prasugrel group (hazard ratio, 1.31 [95% CI, 0.95–1.82]; P =0.10). One-year incidence of all-cause death (4.9% versus 4.7%; P =0.83), stroke (1.3% versus 1.0%; P =0.46), and definite stent thrombosis (1.8% versus 1.0%; P =0.15) did not differ significantly in patients assigned to ticagrelor or prasugrel. One-year incidence of myocardial infarction (5.3% versus 2.8%; hazard ratio, 1.95 [95% CI, 1.18–3.23]; P =0.010) was higher with ticagrelor than with prasugrel. BARC type 3 to 5 bleeding occurred in 46 patients (6.1%) in the ticagrelor group and in 39 patients (5.1%) in the prasugrel group (hazard ratio, 1.22 [95% CI, 0.80–1.87]; P =0.36).

Conclusions:

In patients with ST-segment–elevation myocardial infarction undergoing primary percutaneous coronary intervention, there was no significant difference in the primary end point between prasugrel and ticagrelor. Ticagrelor was associated with a significant increase in the risk for recurrent myocardial infarction.

Registration:

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01944800.

The Rise of Transradial Artery Access for Percutaneous Coronary Intervention in Patients with Acute Coronary Syndromes in Australia

OBJECTIVES

The aim of this study was to evaluate the outcomes of acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) via transradial artery access (TRA) or transfemoral artery access (TFA).

BACKGROUND

Over the last decade, evidence for the benefit of TRA for PCI has grown, leading to a steady uptake of TRA around the world. Despite this, the topic remains controversial with contrary evidence to suggest no significant benefit over TFA.

METHODS

A retrospective study of consecutive ACS patients from 2011 to 2017 who underwent PCI via TRA or TFA. The primary outcome was Major Adverse Cardiovascular Events (MACE), a composite of death, myocardial infarction (MI), target lesion revascularisation (TLR), or coronary artery bypass graft surgery (CABG) at 12 months. Secondary outcomes included Bleeding Academic Research Consortium (BARC) bleeding events scored 2 or higher, haematoma formation, and stent thrombosis, in addition to all individual components of MACE.

RESULTS

We treated 3624 patients (77% male), with PCI via TFA (n = 2391) or TRA (n = 1233). Transradial artery access was associated with a reduction in mortality (3% vs 6.3%; p < 0.0001), MI (1.8% vs 3.9%; p=0.0004), CABG (0.6% vs 1.5%; p=0.0205), TLR (1% vs 2.9%; p < 0.0001), large haematoma (0.4% vs 1.8%; p=0.0003), BARC 2 (0.2% vs 1.1%; p=0.0029), and BARC 3 events (0.4% vs 1.0%; p=0.0426). On multivariate Cox regression analysis, TFA, age ≥ 75, prior PCI, use of bare metal stents, cardiogenic shock, cardiac arrest, and multivessel coronary artery disease were associated with an increased risk of MACE.

CONCLUSION

Despite the limitations secondary to the observational nature of our study and multiple confounders, our results are in line with results of major trials and, as such, we feel that our results support the use of TRA as the preferred access site in patients undergoing PCI for ACS to improve patient outcomes.

The prognostic significance of periprocedural infarction in the era of potent antithrombotic therapy. The PRAGUE-18 substudy

BACKGROUND

The prognostic significance of periprocedural myocardial infarction (MI) remains controversial.

METHODS AND RESULTS

The study aims to investigate the incidence of periprocedural MI in the era of high sensitivity diagnostic markers and intense antithrombotics, and its impact on early outcomes of patients with acute MI treated with primary angioplasty (pPCI). Data from the PRAGUE-18 (prasugrel versus ticagrelor in pPCI) study were analyzed. The primary net-clinical endpoint (EP) included death, spontaneous MI, stroke, severe bleeding, and revascularization at day 7. The key secondary efficacy EP included cardiovascular death, spontaneous MI, and stroke within 30 days. The incidence of peri-pPCI MI was 2.3% (N = 28) in 1230 study patients. The net-clinical EP occurred in 10.7% of patients with, and in 3.6% of patients without, peri-pPCI MI (HR 2.92; 95% CI 0.91-9.38; P = 0.059). The key efficacy EP was 10.7% and 3.2%, respectively (HR 3.44; 95% CI 1.06-11.13; P = 0.028). Patients with periprocedural MI were at a higher risk of spontaneous MI (HR 6.19; 95% CI 1.41-27.24; P = 0.006) and stent thrombosis (HR 10.77; 95% CI 2.29-50.70; P = 0.003) within 30 days. Age, hyperlipidemia, multi-vessel disease, post-procedural TIMI <3, pPCI on circumflex coronary artery, and periprocedural GP IIb/IIIa inhibitor were independent predictors of peri-pPCI MI.

CONCLUSIONS

In the era of intense antithrombotic therapy, the occurrence of peri-pPCI MI is despite highly sensitive diagnostic markers a rare complication, and is associated with an increased risk of early reinfarction and stent thrombosis.

The impact of optimal medical therapy on patients with recurrent acute myocardial infarction: Subanalysis from the BleeMACS study

BACKGROUND

Acute myocardial infarction (AMI) recurrence is still high despite great progress in secondary prevention. Patients with recurrent AMI suffer worse prognosis compared to those with first AMI. The objective was to evaluate the effect of optimal medical therapy (OMT) on these patients with recurrent AMI.

METHODS AND RESULTS

Sub-analysis was performed including 13,343 patients with AMI from the international multicenter Bleeding complications in a Multicenter registry of patients discharged with diagnosis of Acute Coronary Syndrome (BleeMACS) registry. OMT was defined as the combination of aspirin, any P2Y12 inhibitor, statin, angiotensin converting enzyme inhibitor/angiotensin receptor blocker, and beta-blocker. Among 1285 patients with prior AMI, 56.8% received OMT prescription. Patients receiving OMT suffered from less congestive heart failure, peripheral artery disease, malignancy, and bleeding history. Kaplan-Meier survival estimates revealed that OMT was strongly related to decreased in all-cause death (4.2% vs. 10.1%, p < .001) and the composite endpoint of death/re-AMI (11.1% vs. 16.9%, p = .005) at 1-year follow-up. OMT was the independent protect factor of primary endpoint even after adjusting for multiple possible confounders (HR, 0.46; 95% CI, 0.27-0.78; p = .004). However, no significant difference was observed regarding re-AMI between OMT and non-OMT groups. OMT also reduced all-cause death in patients with recurrent AMI after propensity score matching.

CONCLUSIONS

The prescription of OMT was seriously insufficient in patients with recurrent AMI, especially high-risk patients, even though OMT was associated with improved prognosis. Further improvements in pharmacological therapy are needed to reduce subsequent recurrent events.

Comparison of Light Transmission Aggregometry With Impedance Aggregometry in Patients on Potent P2Y12 Inhibitors

Since data on the agreement between light transmission aggregometry (LTA) and multiple electrode aggregometry (MEA) in patients on the more potent P2Y₁₂ inhibitors are missing so far, we investigated if the evaluation of the responsiveness to therapy by LTA can be replaced by MEA in 160 acute coronary syndrome (ACS) patients on dual antiplatelet therapy with aspirin and prasugrel or ticagrelor (n = 80 each). Cut-off values for high on-treatment residual platelet reactivity (HRPR) in response to adenosine diphosphate (ADP) or arachidonic acid (AA) were defined according to previous studies showing an association of HRPR with the occurrence of adverse ischemic outcomes. ADP- inducible platelet aggregation was 33% and 37% (P = 0.07) by LTA and 19 AU and 20 AU (P = 0.38) by MEA in prasugrel- and ticagrelor-treated patients, respectively. AA- inducible platelet aggregation was 2% and 3% by LTA and 15 AU and 16 AU by MEA, (all P ≥ 0.3) in patients on prasugrel and ticagrelor, respectively. By LTA, HRPR ADP and HRPR AA were seen in 5%/5% and in 4%/ 13% of patients receiving prasugrel- and ticagrelor, respectively. By MEA, HRPR ADP and HRPR AA were seen in 3%/ 25% and 0%/24% of prasugrel- and ticagrelor-treated patients, respectively. ADP-inducible platelet reactivity by MEA correlated significantly with LTA ADP in prasugrel-treated patients (r = 0.4, P < 0.001), but not in those receiving ticagrelor (r = 0.09, P = 0.45). AA-inducible platelet aggregation by LTA and MEA did not correlate in prasugrel- and ticagrelor-treated patients. Sensitivity/specificity of HRPR by MEA to detect HRPR by LTA were 25%/99% for MEA ADP and 100%/79% for MEA AA in prasugrel-treated patients, and 0%/100% for MEA ADP and 70%/83% for MEA AA in ticagrelor-treated patients. In conclusion, on-treatment residual ADP-inducible platelet reactivity by LTA and MEA shows a significant correlation in prasugrel- but not ticagrelor-treated patients. However, in both groups LTA and MEA revealed heterogeneous results regarding the classification of patients as responders or non-responders to P2Y₁₂ inhibition.

Association of Ticagrelor vs Clopidogrel With Net Adverse Clinical Events in Patients With Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention

Importance

Current guidelines recommend ticagrelor as the preferred P2Y12 platelet inhibitor for patients with acute coronary syndrome (ACS), primarily based on a single large randomized clinical trial. The benefits and risks associated with ticagrelor vs clopidogrel in routine practice merits attention.

Objective

To determine the association of ticagrelor vs clopidogrel with ischemic and hemorrhagic events in patients undergoing percutaneous coronary intervention (PCI) for ACS in clinical practice.

Design, Setting, and Participants

A retrospective cohort study of patients with ACS who underwent PCI and received ticagrelor or clopidogrel was conducted using 2 United States electronic health record-based databases and 1 nationwide South Korean database from November 2011 to March 2019. Patients were matched using a large-scale propensity score algorithm, and the date of final follow-up was March 2019.

Exposures

Ticagrelor vs clopidogrel.

Main Outcomes and Measures

The primary end point was net adverse clinical events (NACE) at 12 months, composed of ischemic events (recurrent myocardial infarction, revascularization, or ischemic stroke) and hemorrhagic events (hemorrhagic stroke or gastrointestinal bleeding). Secondary outcomes included NACE or mortality, all-cause mortality, ischemic events, hemorrhagic events, individual components of the primary outcome, and dyspnea at 12 months. The database-level hazard ratios (HRs) were pooled to calculate summary HRs by random-effects meta-analysis.

Results

After propensity score matching among 31 290 propensity-matched pairs (median age group, 60-64 years; 29.3% women), 95.5% of patients took aspirin together with ticagrelor or clopidogrel. The 1-year risk of NACE was not significantly different between ticagrelor and clopidogrel (15.1% [3484/23 116 person-years] vs 14.6% [3290/22 587 person-years]; summary HR, 1.05 [95% CI, 1.00-1.10]; P = .06). There was also no significant difference in the risk of all-cause mortality (2.0% for ticagrelor vs 2.1% for clopidogrel; summary HR, 0.97 [95% CI, 0.81-1.16]; P = .74) or ischemic events (13.5% for ticagrelor vs 13.4% for clopidogrel; summary HR, 1.03 [95% CI, 0.98-1.08]; P = .32). The risks of hemorrhagic events (2.1% for ticagrelor vs 1.6% for clopidogrel; summary HR, 1.35 [95% CI, 1.13-1.61]; P = .001) and dyspnea (27.3% for ticagrelor vs 22.6% for clopidogrel; summary HR, 1.21 [95% CI, 1.17-1.26]; P < .001) were significantly higher in the ticagrelor group.

Conclusions and Relevance

Among patients with ACS who underwent PCI in routine clinical practice, ticagrelor, compared with clopidogrel, was not associated with significant difference in the risk of NACE at 12 months. Because the possibility of unmeasured confounders cannot be excluded, further research is needed to determine whether ticagrelor is more effective than clopidogrel in this setting.

Ticagrelor Inhibits Toll-Like and Protease-Activated Receptor Mediated Platelet Activation in Acute Coronary Syndromes

Purpose

Since ticagrelor inhibits the cellular uptake of adenosine, thereby increasing extracellular adenosine concentration and biological activity, we hypothesized that ticagrelor has adenosine-dependent antiplatelet properties. In the current study, we compared the effects of ticagrelor and prasugrel on platelet activation in acute coronary syndrome (ACS).

Methods

Platelet surface expression of P-selectin and activated glycoprotein (GP) IIb/IIIa in response to adenosine diphosphate (ADP), the toll-like receptor (TLR)-1/2 agonist Pam3CSK4, the TLR-4 agonist lipopolysaccharide (LPS), the protease-activated receptor (PAR)-1 agonist SFLLRN, and the PAR-4 agonist AYPGKF were measured by flow cytometry in blood from 80 ticagrelor- and 80 prasugrel-treated ACS patients on day 3 after percutaneous coronary intervention. Residual platelet aggregation to arachidonic acid (AA) and ADP were assessed by multiple electrode aggregometry and light transmission aggregometry.

Results

ADP-induced platelet activation and aggregation, and AA-induced platelet aggregation were similar in patients on ticagrelor and prasugrel, respectively (all p ≥ 0.3). Further, LPS-induced platelet surface expression of P-selectin and activated GPIIb/IIIa did not differ significantly between ticagrelor- and prasugrel-treated patients (both p > 0.4). In contrast, Pam3CSK4-induced platelet surface expression of P-selectin and activated GPIIb/IIIa were significantly lower in ticagrelor-treated patients (both p ≤ 0.005). Moreover, SFLLRN-induced platelet surface expression of P-selectin and activated GPIIb/IIIa were significantly less pronounced in patients on ticagrelor therapy compared to prasugrel-treated patients (both p < 0.03). Finally, PAR-4 mediated platelet activation as assessed by platelet surface expression of activated GPIIb/IIIa following stimulation with AYPGKF was significantly lower in patients receiving ticagrelor (p = 0.02).

Conclusion

Ticagrelor inhibits TLR-1/2 and PAR mediated platelet activation in ACS patients more strongly than prasugrel.

Efficacy and safety of newer P2Y12 inhibitors for acute coronary syndrome: a network meta-analysis

Whether newer P2Y12 inhibitors are more efficacious and safer than clopidogrel and whether there is a superior one remain uncertain. We compared the effect of P2Y12 inhibitors on clinical outcomes in patients with acute coronary syndrome (ACS). Randomized controlled trials comparing clopidogrel, prasugrel, ticagrelor, or cangrelor, in combination with aspirin were searched. Sixteen trials with altogether 77,896 patients were included. Compared to clopidogrel, cardiovascular mortality was reduced with prasugrel (OR 0.85, 95% CI 0.75-0.97) and ticagrelor (0.82, 0.73-0.93). Myocardial infarction (0.75, 0.63-0.89) and major adverse cardiovascular events (0.80, 0.69-0.94) were reduced by prasugrel. Stent thrombosis was reduced by prasugrel (0.49, 0.38-0.63), ticagrelor (0.72, 0.57-0.90), and cangrelor (0.59, 0.43-0.81). It was reduced more by prasugrel than ticagrelor (0.69, 0.51-0.93). There were more major bleeds with prasugrel (1.24, 1.05-1.48). Thrombolysis in Myocardial Infarction (TIMI) major bleeding was increased with prasugrel compared to clopidogrel (1.36, 1.11-1.66) and ticagrelor (1.33, 1.06-1.67). TIMI minor bleeding was increased with prasugrel (1.44, 1.16-1.77) and cangrelor (1.47, 1.01-2.16) compared to clopidogrel while it was increased with prasugrel compared to ticagrelor (1.32, 1.01-1.72). Prasugrel is preferable to those ACS patients at low bleeding risk to reduce cardiovascular events whereas ticagrelor is a relatively safe antiplatelet drug of choice for most patients.

Meta-Analysis Comparing the Safety and Efficacy of Prasugrel and Ticagrelor in Acute Coronary Syndrome

Prasugrel and ticagrelor are preferred over clopidogrel for patients with acute coronary syndrome who underwent percutaneous coronary intervention. We sought to determine the relative merits of 1 agent over the other. Multiple databases were queried to identify relevant randomized control trials (RCTs) and observational cohort studies. Random-effects model was used to calculate an unadjusted odds ratio (OR) for major adverse cardiovascular and cerbrovascular events (MACCE) and its components. A total of 27 (7 RCTs, 20 observational cohort studies) studies comprising 118,266 (prasugrel 62,716, ticagrelor 51,196) patients were included. At 30 days, prasugrel was associated with a significantly lower odds of MACCE (OR 0.75, 95% confidence interval [CI] 0.67 to 0.85, p ≤0.0001) and mortality (OR 0.65, 95% CI 0.59 to 0.71, p ≤0.0001). At 1 year, the overall odds of mortality favored prasugrel (OR 0.79, 95% CI 0.68 to 0.92, p = 0.002), but no significant interdrug difference was seen in terms of MACCE (OR 0.89, 95% CI 0.76 to 1.05, p = 0.16). There was no significant difference in the odds of overall myocardial infarction, revascularization, stent thrombosis, stroke, and major bleeding events between the 2 groups on both 30-day and 1-year follow-up. A subgroup analysis of RCTs data showed no significant difference between prasugrel and ticagrelor in terms of any end point at all time points. In conclusion, prasugrel might have lower odds of MACCE and mortality at 30 days. However, there was no difference in the safety and efficacy end points of 2 drugs at 1 year. The observed transient prasugrel-related mortality benefits were subject to the bias of nonrandomized assignment.

Ticagrelor in the management of coronary artery disease

Ticagrelor is a potent and orally active P2Y₁₂ inhibitor. Ticagrelor has been extensively tested in Phase II and Phase III trials in patients with coronary artery disease. The pharmacokinetics and pharmacodynamics of ticagrelor result in more rapid and effective inhibition of platelet activation compared with other P2Y₁₂ inhibitors. This has resulted in a reduction in recurrent major cardiovascular events in initial randomized controls trials comparing ticagrelor with clopidogrel. More recently, clinical trials have investigated the use of ticagrelor in patients with stable coronary artery disease and a high residual risk of coronary thrombotic events. In patients with stable coronary artery disease, the potent antiplatelet effect of ticagrelor is counterbalanced by an increased risk of major bleeding. Further research is ongoing to determine the optimal duration of ticagrelor therapy.

De-Escalation of Antiplatelet Treatment in Patients with Myocardial Infarction Who Underwent Percutaneous Coronary Intervention: A Review of the Current Literature

In acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI), treatment with the P2Y12 inhibitors ticagrelor or prasugrel is recommended over clopidogrel due to a better efficacy, albeit having more bleeding complication. These higher bleeding rates have provoked trials investigating de-escalation from ticagrelor or prasugrel to clopidogrel in the hope of reducing bleeding without increasing thrombotic event rates. In this review, we sought to present an overview of the major trials investigating several different options for de-escalation; unguided, platelet function testing- and genotype-guided. Based on these results, and on other established literature sources, such as guidelines and expert consensus papers, we provide an overview to help decide when and how to de-escalate antiplatelet therapy in ACS patients undergoing PCI.

An updated drug profile of ticagrelor with considerations on the treatment of patients with coronary artery disease and diabetes mellitus

INTRODUCTION

Ticagrelor is an antiplatelet agent acting through direct and reversible competitive inhibition of the platelet P2Y₁₂ receptor. While the clinical merits of ticagrelor in patients who experienced an acute coronary syndrome are widely accepted, its role in stable coronary artery disease is less established. Recently, large-scale trials of ticagrelor have been published in this setting, including a trial in patients with diabetes mellitus (DM).

AREAS COVERED

This review aims to inform about recent findings on ticagrelor, by appraising the current body of evidence on its use in different clinical scenarios, particularly in DM, ranging from pharmacology to clinical outcomes and future directions.

EXPERT OPINION

The results of the THEMIS trial, conducted in DM patients with stable coronary artery disease and no prior stroke or myocardial infarction, showed that although ticagrelor in addition to aspirin reduced the risk of ischemic events, this was associated with a parallel increase in bleeding complications. However, patients with history of percutaneous coronary intervention seemed to benefit more from adjunctive ticagrelor therapy. Careful bleeding and ischemic risk stratification remains crucial to define the best antithrombotic strategy for the individual patient.

The Effect of Diabetes on Prognosis Following Myocardial Infarction Treated with Primary Angioplasty and Potent Antiplatelet Therapy

PURPOSE

To investigate the prognostic significance of diabetes mellitus (DM) in patients with high risk acute myocardial infarction (AMI) treated with primary percutaneous coronary intervention (pPCI) in the era of potent antithrombotics.

METHODS

Data from 1230 ST-segment elevation myocardial infarction (STEMI) patients enrolled in the PRAGUE-18 (prasugrel vs. ticagrelor in pPCI) study were analyzed. Ischemic and bleeding event rates were calculated for patients with and without diabetes. The independent impact of diabetes on outcomes was evaluated after adjustment for outcome predictors.

RESULTS

The prevalence of DM was 20% (N = 250). Diabetics were older and more often female. They were more likely to have hypertension, hyperlipoproteinemia, multivessel coronary disease and left main disease, and be obese. The primary net-clinical endpoint (EP) containing death, spontaneous nonfatal MI, stroke, severe bleeding, and revascularization at day 7 occurred in 6.1% of patients with, and in 3.5% of patients without DM (HR 1.8; 95% CI 0.978-3.315; P = 0.055). At one year, the key secondary endpoint defined as cardiovascular death, spontaneous MI, or stroke occurred in 8.8% with, and 5.5% without DM (HR 1.621; 95% CI 0.987-2.661; P = 0.054). In those with DM the risk of total one-year mortality (6.8% vs. 3.9% (HR 1.773; 95% CI 1.001-3.141; P = 0.047)) and the risk of nonfatal reinfarction (4.8% vs. 2.2% (HR 2.177; 95% CI 1.077-4.398; P = 0.026)) were significantly higher compared to in those without DM. There was no risk of major bleeding associated with DM (HR 0.861; 95% CI 0.554-1.339; P = 0.506). In the multivariate analysis, diabetes was independently associated with the one-year risk of reinfarction (HR 2.176; 95% Confidence Interval, 1.055-4.489; p = 0.035).

CONCLUSION

Despite best practices STEMI treatment, diabetes is still associated with significantly worse prognoses, which highlights the importance of further improvements in the management of this high-risk population.

Efficacy and Safety of Clopidogrel, Prasugrel and Ticagrelor in ACS Patients Treated with PCI: A Propensity Score Analysis of the RENAMI and BleeMACS Registries

INTRODUCTION

Real-life data comparing clopidogrel, prasugrel, and ticagrelor for unselected patients undergoing percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) are lacking, as are data for the temporal distribution of ischemic and bleeding risks.

METHODS

A total of 19,825 patients were enrolled from the RENAMI and BleeMACS registries. Both were multicenter, retrospective, observational registries including the data and outcomes of consecutive patients with ACS who underwent primary PCI and were discharged with dual antiplatelet therapy (DAPT). We evaluated the long-term outcome stratified by the different antiplatelet agents.

RESULTS

A total of 14,105 patients (71.2%) were treated with clopidogrel, 2364 patients (11.9%) with prasugrel and 3356 patients (16.9%) with ticagrelor. After propensity score matching, at 1 year, prasugrel reduced the incidence of net adverse clinical events (NACE; a composite endpoint of all-cause death, myocardial infarction [MI] and Bleeding Academic Research Consortium [BARC] 3-5 bleeding) (4.2% vs.7.6%, p = 0.002) and of major adverse cardiovascular events (MACE; a composite endpoint of death and MI) compared with clopidogrel (2.6% vs. 5.2%, p = 0.007). Ticagrelor decreased rates of MACE compared with clopidogrel (2.7% vs. 6.2%, p < 0.001), but not of NACE (6.6% vs. 8.7%, p = 0.07). Ticagrelor presented similar performance in terms of MACE compared with prasugrel (2.8% vs. 2.4%, p = 0.56), with a trend towards a reduction in MI (0.2% vs. 0.4%, p = 0.56), but with higher risk of BARC 3-5 bleedings (3.8% vs. 1.7%, p = 0.04). In the daily risk analysis, clopidogrel presented a binomial distribution with a peak of ischemic risk at 3 months, which decreased towards bleedings; prasugrel had a constant equivalence between opposite risks; and ticagrelor constantly reduced recurrent MIs despite higher risk of BARC 3-5 events.

CONCLUSION

In real life, ticagrelor is more effective in reducing ischemic events during the first year after ACS, despite an increased risk of major bleedings, while prasugrel assures a better balance between ischemic and bleeding recurrent events.

De-escalation therapy after acute coronary syndrome: is it reasonable to switch from prasugrel (or ticagrelor) to clopidogrel early?

Dual antiplatelet treatment (DAPT) is the treatment of choice to prevent atherothrombotic events in patients with acute coronary syndrome (ACS) treated with percutaneous interventions (PCIs). The availability of different P2Y12 inhibitors set the stage for costum made DAPT, as to achieve the highest profile of safety and efficacy. The de-escalation therapy for the newer and more powerful antiplatelet drugs, such as ticagrelor and prasugrel, to clopidogrel, is a strategy for patients with recent ACS, unfit for continuing DAPT for their high risk of bleeding, or side effects, or socio-economic reasons, but without a prohibitive ischaemic risk. There is a need for compelling clinical evidences able to provide the clinical cardiologist with the necessary information to decide the best antiplatelet strategy for each individual patient.

Comparative Efficacy and Safety of Oral P2Y12 Inhibitors in Acute Coronary Syndrome: Network Meta-Analysis of 52 816 Patients From 12 Randomized Trials

BACKGROUND

New randomized, controlled trials have become available on oral P2Y₁₂ inhibitors in acute coronary syndrome. We aimed to evaluate current evidence comparing the efficacy and safety profile of prasugrel, ticagrelor, and clopidogrel in acute coronary syndrome by a meta-analysis of randomized controlled trials.

METHODS

We performed a network meta-analysis and direct pairwise comparison analysis of efficacy and safety outcomes from 12 randomized controlled trials including a total of 52 816 patients with acute coronary syndrome.

RESULTS

In comparison with clopidogrel, ticagrelor significantly reduced cardiovascular mortality (hazard ratio [HR], 0.82 [95% CI, 0.72-0.92]) and all-cause mortality (HR, 0.83 [95% CI, 0.75-0.92]), whereas there was no statistically significant mortality reduction with prasugrel (HR, 0.90 [95% CI, 0.80-1.01] and HR, 0.92 [95% CI, 0.84-1.02], respectively). In comparison with each other, there were no significant differences in mortality (HR prasugrel versus ticagrelor, 1.10 [95% CI, 0.94-1.29] and 1.12 [95% CI, 0.98-1.28]). In comparison with clopidogrel, prasugrel reduced myocardial infarction (HR, 0.81 [95% CI, 0.67-0.98]), whereas ticagrelor showed no risk reduction (HR, 0.97 [95% CI, 0.78-1.22]). Differences between prasugrel and ticagrelor were not statistically significant. Stent thrombosis risk was significantly reduced by both ticagrelor and prasugrel versus clopidogrel (28%-50% range of reduction). In comparison with clopidogrel, both prasugrel (HR, 1.26 [95% CI, 1.01-1.56]) and ticagrelor (HR, 1.27 [95% CI, 1.04-1.55]) significantly increased major bleeding. There were no significant differences between prasugrel and ticagrelor for all outcomes explored.

CONCLUSIONS

Prasugrel and ticagrelor reduced ischemic events and increased bleeding in comparison with clopidogrel. A significant mortality reduction was observed with ticagrelor only. There was no efficacy and safety difference between prasugrel and ticagrelor. Registration: URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42019155648.

Ticagrelor-based antiplatelet regimens in patients with atherosclerotic artery disease-A meta-analysis of randomized clinical trials

BACKGROUND

Randomized trials did not consistently support superiority of ticagrelor, as monotherapy or in combination with aspirin, in terms of efficacy or safety, in patients with atherosclerotic artery disease.

METHODS

Medline, EMBASE, the Cochrane Central Register of Controlled Trials, and scientific session abstracts were searched for trials of patients with coronary or peripheral artery disease (with >1,000 participants and a follow-up ≥3 months) randomly assigned to ticagrelor-based or conventional antiplatelet therapies. Trial-level hazard ratios (HRs) were pooled using a fixed- or random-effect model (in case of significant heterogeneity) with the inverse variance weighting. The primary outcome was all-cause mortality. Other outcomes were myocardial infarction (MI), stroke, and major bleeding.

RESULTS

Overall 77,489 patients received either ticagrelor-based (n = 38,721) or conventional antiplatelet regimens (n = 38,768) in 6 trials. The primary outcome occurred in 4.5% of patients treated with experimental therapy and 4.9% of patients treated with control therapy (HR = 0.91, 95% CI 0.81-1.01; P = .07). Overall, patients treated with ticagrelor-based versus conventional antiplatelet regimens showed no significant difference in terms of all-cause death, MI, stroke, or major bleeding after 20 months. However, in trials of patients with coronary artery disease as primary diagnosis, the risk for all-cause death (HR = 0.84 [0.77-0.91], P < .001) and MI (HR = 0.87 [0.80-0.94], P = .007) was significantly reduced by experimental therapy.

CONCLUSIONS

In patients with atherosclerotic artery disease, the benefit of ticagrelor-based therapies was confined to patients treated for coronary artery disease. The drug significantly reduced the risk for all-cause death and MI without excess risk of bleeding in these patients. In consideration of limitations of subgroup analyses, these results need further validation.

Beneficial Effects of Ticagrelor on Oxidized Low-Density Lipoprotein (ox-LDL)-Induced Apoptosis in Human Umbilical Vein Endothelial Cells

Background

Ticagrelor is the first oral anti-platelet agent which has direct anti-platelet aggregation effect by combining with ADP P2Y12 receptors in platelets. It has been approved to reduce the incidence of thrombus cardiovascular events in acute coronary syndrome patients. However, the effects of ticagrelor on endothelial apoptosis have not been investigated.

Material/Methods

Oxidized low-density lipoprotein (ox-LDL) was used to establish a human umbilical vein endothelial cell (HUVEC) apoptosis model. To investigate the effects of ticagrelor on endothelial apoptosis, the HUVECs were treated with different dose of ticagrelor. Apoptosis rates of HUVECs was evaluated by flow cytometry, and the expression levels of Akt, p-Akt, Bcl-2, Bax, caspase-3, endothelial nitric oxide synthase (eNOS), and nitric oxide (NO) concentration were assessed.

Results

After treatment with 50 ug/mL ox-LDL or 100 ug/mL ox-LDL, we found that the late apoptosis and necrosis rate and the expression levels of Bax and caspase-3 were significantly increased in HUVECs, whereas the expression levels of Akt, p-Akt, Bcl-2, eNOS, and NO were significantly decreased. Ticagrelor restored the apoptosis rate of ox-LDL-induced HUVECs in a dose-dependent manner. In addition, compared with ox-LDL group, ticagrelor treatment significantly increased the expression levels of Akt, p-Akt, Bcl-2, eNOS, and NO concentration, and significantly decreased the expression levels of Bax and caspase-3.

Conclusions

We found that ox-LDL induced significant apoptosis and necrosis in our model, which was dose-dependently improved by ticagrelor. These changes might be explained by alterations in apoptosis and antioxidant pathways.

Prescription Patterns of Clopidogrel, Prasugrel, and Ticagrelor After Percutaneous Coronary Intervention With Stent Implantation (from the NCDR PINNACLE Registry)

The use of prasugrel and ticagrelor as part of dual antiplatelet therapy is increasing in patients after percutaneous coronary intervention (PCI). Accordingly, we aimed to evaluate their prescription patterns in the National Cardiovascular Data Registry (NCDR) Practice Innovation and Clinical Excellence (PINNACLE) registry. We analyzed patients enrolled in NCDR PINNACLE registry from January 2013 to March 2015 who underwent PCI with drug-eluting stent and were prescribed dual antiplatelet therapy. All patients received aspirin. The primary study outcome was a 3-level variable denoting the second antiplatelet agent prescribed: (1) clopidogrel, (2) prasugrel, or (3) ticagrelor. Baseline characteristics were compared among the 3 groups. Odds ratios and 95% credible intervals were calculated from a nested hierarchical Bayesian logistic regression models to identify independent predictors of prescription of antiplatelet medications, incorporating practice and provider as random effects. Our study cohort consisted of 26,710 patients during our study period January 2013 to March 2015. Seventy nine percent of patients were prescribed clopidogrel, 12% prasugrel, and 11% ticagrelor. Patients aged ≥75 years, women, history of tobacco use, Peripheral Arterial Disease (PAD), hypertension, diabetes, previous vascular complication, heart failure, and stroke/transient ischemic attack were more likely to be on clopidogrel than prasugrel or ticagrelor. The relative percentages of ticagrelor and prasugrel were higher in patients with history of myocardial infarction, compared with those without myocardial infarction. In summary, our study highlights the prescription patterns associated with prescription of antiplatelet agents after PCI. We found that both ticagrelor and prasugrel were mostly prescribed per the current practice guidelines, thus reflecting appropriate guideline adherence by practices in NCDR PINNACLE registry.

Antithrombotic Therapy for Percutaneous Cardiovascular Interventions: From Coronary Artery Disease to Structural Heart Interventions

Percutaneous cardiovascular interventions have changed dramatically in recent years, and the impetus given by the rapid implementation of novel techniques and devices have been mirrored by a refinement of antithrombotic strategies for secondary prevention, which have been supported by a significant burden of evidence from clinical studies. In the current manuscript, we aim to provide a comprehensive, yet pragmatic, revision of the current available evidence regarding antithrombotic strategies in the domain of percutaneous cardiovascular interventions. We revise the evidence regarding antithrombotic therapy for secondary prevention in coronary artery disease and stent implantation, the complex interrelation between antiplatelet and anticoagulant therapy in patients undergoing percutaneous coronary intervention with concomitant atrial fibrillation, and finally focus on the novel developments in the secondary prevention after structural heart disease intervention. A special focus on treatment individualization is included to emphasize risk and benefits of each therapeutic strategy.

Prognostic Value of MicroRNAs in Patients after Myocardial Infarction: A Substudy of PRAGUE-18

Background

The evaluation of the long-term risk of major adverse cardiovascular events and cardiac death in patients after acute myocardial infarction (AMI) is an established clinical process. Laboratory markers may significantly help with the risk stratification of these patients. Our objective was to find the relation of selected microRNAs to the standard markers of AMI and determine if these microRNAs can be used to identify patients at increased risk.

Methods

Selected microRNAs (miR-1, miR-133a, and miR-499) were measured in a cohort of 122 patients from the PRAGUE-18 study (ticagrelor vs. prasugrel in AMI treated with primary percutaneous coronary intervention (pPCI)). The cohort was split into two subgroups: 116 patients who did not die (survivors) and 6 patients who died (nonsurvivors) during the 365-day period after AMI. Plasma levels of selected circulating miRNAs were then assessed in combination with high-sensitivity cardiac troponin T (hsTnT) and N-terminal probrain natriuretic peptide (NT-proBNP).

Results

miR-1, miR-133a, and miR-499 correlated positively with NT-proBNP and hsTnT 24 hours after admission and negatively with left ventricular ejection fraction (LVEF). Both miR-1 and miR-133a positively correlated with hsTnT at admission. Median relative levels of all selected miRNAs were higher in the subgroup of nonsurvivors (N = 6) in comparison with survivors (N = 116), but the difference did not reach statistical significance. All patients in the nonsurvivor subgroup had miR-499 and NT-proBNP levels above the cut-off values (891.5 ng/L for NT-proBNP and 0.088 for miR-499), whereas in the survivor subgroup, only 28.4% of patients were above the cut-off values (p = 0.001).

Conclusions

Statistically significant correlation was found between miR-1, miR-133a, and miR-499 and hsTnT, NT-proBNP, and LVEF. In addition, this analysis suggests that plasma levels of circulating miR-499 could contribute to the identification of patients at increased risk of death during the first year after AMI, especially when combined with NT-proBNP levels.

Ticagrelor or Prasugrel in Patients with Acute Coronary Syndromes

BACKGROUND

The relative merits of ticagrelor as compared with prasugrel in patients with acute coronary syndromes for whom invasive evaluation is planned are uncertain.

METHODS

In this multicenter, randomized, open-label trial, we randomly assigned patients who presented with acute coronary syndromes and for whom invasive evaluation was planned to receive either ticagrelor or prasugrel. The primary end point was the composite of death, myocardial infarction, or stroke at 1 year. A major secondary end point (the safety end point) was bleeding.

RESULTS

A total of 4018 patients underwent randomization. A primary end-point event occurred in 184 of 2012 patients (9.3%) in the ticagrelor group and in 137 of 2006 patients (6.9%) in the prasugrel group (hazard ratio, 1.36; 95% confidence interval [CI], 1.09 to 1.70; P = 0.006). The respective incidences of the individual components of the primary end point in the ticagrelor group and the prasugrel group were as follows: death, 4.5% and 3.7%; myocardial infarction, 4.8% and 3.0%; and stroke, 1.1% and 1.0%. Definite or probable stent thrombosis occurred in 1.3% of patients assigned to ticagrelor and 1.0% of patients assigned to prasugrel, and definite stent thrombosis occurred in 1.1% and 0.6%, respectively. Major bleeding (as defined by the Bleeding Academic Research Consortium scale) was observed in 5.4% of patients in the ticagrelor group and in 4.8% of patients in the prasugrel group (hazard ratio, 1.12; 95% CI, 0.83 to 1.51; P = 0.46).

CONCLUSIONS

Among patients who presented with acute coronary syndromes with or without ST-segment elevation, the incidence of death, myocardial infarction, or stroke was significantly lower among those who received prasugrel than among those who received ticagrelor, and the incidence of major bleeding was not significantly different between the two groups. (Funded by the German Center for Cardiovascular Research and Deutsches Herzzentrum München; ISAR-REACT 5 ClinicalTrials.gov number, NCT01944800.).

P2Y12 inhibitors for the treatment of acute coronary syndrome patients undergoing percutaneous coronary intervention: current understanding and outcomes

Introduction: Inhibition of P2Y₁₂ platelet receptors consists a crucial target of pharmacologic treatment in acute coronary syndrome patients. Several controversial issues however still remain and these are analyzed.Areas covered: The significance of early and strong platelet inhibition in the early phase of STEMI and the role of pretreatment are discussed. Concerns regarding morphine administration are raised. The role of crushing integral tablets to expedite the onset of action of oral P2Y₁₂ inhibitors is emphasized. New data on the intravenous cangrelor are reported. Antiplatelet therapies as adjunct to thrombolysis, as well as the role of de-escalation antiplatelet therapy are analyzed.Expert opinion: Pharmacodynamic studies convincingly demonstrate a gap in the onset of antiplatelet action in STEMI cases, even when prasugrel or ticagrelor loading dose is used. The clinical benefit, however, of the early platelet inhibition and pretreatment is not entirely clear. Morphine delays the onset of action of oral agents, while this is expedited by crushing the integral tablets. Cangrelor devoids of these deficiencies by achieving fast and strong platelet inhibition in all clinical scenarios. Concomitant administration of novel antiplatelet agents with thrombolysis and de-escalation of antiplatelet treatment necessitate further study to reach definite conclusion.

Prasugrel vs. Ticagrelor for Acute Coronary Syndrome Patients Undergoing Percutaneous Coronary Intervention: A Systematic Review and Meta-Analysis

BACKGROUND

The newer P2Y₁₂ inhibitors have better efficacy than clopidogrel. However, whether ticagrelor or prasugrel have a better comparative safety and efficacy profile, especially in the long-term, remains inconclusive.

OBJECTIVE

We compared prasugrel and ticagrelor in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI).

METHODS

MEDLINE and the Cochrane library were queried for randomized controlled trials (RCTs) or observational studies comparing prasugrel with ticagrelor in patients with ACS undergoing PCI. Random-effects pooling was used to calculate odds ratios (ORs) with 95% confidence intervals (CI). Analyses were stratified by duration of follow-up (short term [≤ 3 months] and long term [≥ 1 year]) and study design.

RESULTS

In total, 14 studies (six RCTs, eight observational studies), including 40,188 patients, met eligibility criteria. Pooled analysis did not indicate that prasugrel significantly decreased all-cause mortality compared with ticagrelor in the short term (OR 0.49; 95% CI 0.20-1.20; p = 0.11) or long term (OR 0.74; 95% CI 0.48-1.15; p = 0.38). Pooled observational studies showed significantly lower long-term all-cause mortality (OR 0.63; 95% CI 0.43-0.92; p = 0.02) and short-term stent thrombosis (OR 0.46; 95% CI 0.28-0.75; p = 0.002) with prasugrel. No significant difference was observed in the risk of nonfatal myocardial infarction, ischemic stroke, bleeding, or repeat revascularization between the two groups. Results remained similar after stratification according to follow-up and study design.

CONCLUSIONS

The present analysis suggests that prasugrel might have a better efficacy profile than ticagrelor in patients with ACS undergoing PCI. However, this advantage was only seen in pooled observational studies and is likely to be affected by selection bias.

An Update on Radial Artery Access and Best Practices for Transradial Coronary Angiography and Intervention in Acute Coronary Syndrome: A Scientific Statement From the American Heart Association

Transradial artery access for percutaneous coronary intervention is associated with lower bleeding and vascular complications than transfemoral artery access, especially in patients with acute coronary syndromes. A growing body of evidence supports adoption of transradial artery access to improve acute coronary syndrome-related outcomes, to improve healthcare quality, and to reduce cost. The purpose of this scientific statement is to propose and support a "radial-first" strategy in the United States for patients with acute coronary syndromes. This document also provides an update to previously published statements on transradial artery access technique and best practices, particularly as they relate to the management of patients with acute coronary syndromes.

Safety and Effectiveness of Contemporary P2Y12 Inhibitors in an East Asian Population With Acute Coronary Syndrome: A Nationwide Population-Based Cohort Study

Background

Prior reports indicate that the effect of P2Y₁₂ inhibitors may be different in East Asian patients (“East Asian paradox”); therefore, understanding the outcomes associated with potent P2Y₁₂ inhibitors in different populations is clinically important.

Methods and Results

In this observational cohort study using administrative healthcare data sets, we compared safety and effectiveness of contemporary P2Y₁₂ inhibitors in patients with acute coronary syndrome. The primary safety outcomes were major and any bleeding, and the primary effectiveness outcomes were major cardiovascular events (a composite of cardiovascular death, myocardial infarction, or stroke) and all‐cause mortality. Among 70 715 patients with acute coronary syndrome, 56 216 (79.5%) used clopidogrel, 11 402 (16.1%) used ticagrelor, and 3097 (4.4%) used prasugrel. The median follow‐up period was 18.0 months (interquartile range: 9.6–26.4 months). In a propensity‐matched cohort, compared with clopidogrel, ticagrelor was associated with a higher risk of any bleeding (hazard ratio: 1.23; 95% CI, 1.14–1.33) but a lower risk of mortality (hazard ratio: 0.76; 95% CI, 0.63–0.91). Prasugrel, compared with clopidogrel, was associated with higher risks of any bleeding (hazard ratio: 1.23; 95% CI, 1.06–1.43) and major bleeding (hazard ratio: 1.50; 95% CI, 1.01–2.21) but a similar risk of effectiveness outcomes. No significant difference was noted between ticagrelor and prasugrel with respect to key safety or effectiveness outcomes. Several sensitivity analyses showed similar results.

Conclusions

In East Asian patients with acute coronary syndrome, compared with clopidogrel, ticagrelor was associated with an increased risk of bleeding but a decreased risk of mortality. Prasugrel was associated with an increase of any bleeding without difference in effectiveness outcomes. The risks of bleeding and ischemic events were similar between ticagrelor and prasugrel.

Protease-activated receptor-mediated platelet aggregation in acute coronary syndrome patients on potent P2Y12 inhibitors

BACKGROUND

Despite the increasing use of potent P2Y12 inhibitors, further atherothrombotic events still impair the prognosis of many acute coronary syndrome (ACS) patients. This may in part be attributable to intact platelet aggregation via the human thrombin receptors protease-activated receptor (PAR)-1 and PAR-4.

OBJECTIVE

We studied PAR mediated platelet aggregation in ACS patients following percutaneous coronary intervention (PCI) with stent implantation in a cross-sectional study.

METHODS

Platelet aggregation to ADP as well as to the PAR-1 agonist SFLLRN and the PAR-4 agonist AYPGKF was assessed by multiple electrode aggregometry in 194 ACS patients on dual antiplatelet therapy with aspirin and either prasugrel (n = 114) or ticagrelor (n = 80) 3 days after PCI.

RESULTS

Based on the consensus cutoff value, high on-treatment residual platelet reactivity to ADP (HRPR ADP) was observed in only 2 prasugrel-treated patients. Both patients with HRPR ADP had also a normal response to SFLLRN and AYPGKF. Among the 112 prasugrel-treated patients with adequate P2Y12 inhibition, 50 patients (45%) still had a normal response to SFLLRN, and 70 patients (63%) still had a normal response to AYPGKF. Among the 80 ticagrelor-treated patients with adequate P2Y12 inhibition, 25 patients (31%) still had a normal response to SFLLRN, and 50 (63%) still had a normal response to AYPGKF.

CONCLUSION

Normal platelet aggregation via PAR-1 and PAR-4 is preserved in many patients with adequate P2Y12 inhibition by prasugrel and ticagrelor. The present findings may at least in part explain adverse ischemic events despite potent P2Y12 inhibition.

De-escalation from ticagrelor to clopidogrel in acute coronary syndrome patients: a systematic review and meta-analysis

De-escalation from ticagrelor to clopidogrel in acute coronary syndrome (ACS) may occur for a variety of reasons, including side effects (bleeding and non-bleeding) and costs. This study sought to assess the prevalence of de-escalation from ticagrelor to clopidogrel and the occurrence of adverse clinical outcomes following de-escalation. We conducted a systematic review of clinical trials and real-world studies in ACS patients treated with ticagrelor. Real-world data on the prevalence of de-escalation during hospitalization or at discharge, after hospital discharge, and during the whole study period were included for meta-analysis. Major adverse cardiovascular events (MACE) and bleeding events occurring after de-escalation were also assessed. A total of 12 studies were eligible for meta-analysis of the prevalence of de-escalation. De-escalation from ticagrelor to clopidogrel therapy occurred with a mean prevalence of 19.8% [95% confidence interval (CI) 11.2-28.4%]. De-escalation occurred more frequently in-hospital or at discharge than after hospital discharge (23.7% vs. 15.8%). For assessment of clinical outcomes, a total of six studies were eligible for meta-analysis. Mean rate of MACE for patients with de-escalation was 2.1% (95% CI 1.1-4.1%) and the rate of major bleeding events was 1.3% (95% CI 0.4-4.5%). In conclusion, de-escalation commonly occurs in real-world practice. Although rates of major cardiovascular and bleeding events in this analysis were generally low, the profile of patients suitable for de-escalation, the impact of de-escalation on adverse clinical outcomes and how this is affected by the timing after index ACS warrants further large-scale investigation.

Switching to Clopidogrel in Patients With Acute Coronary Syndrome Managed With Percutaneous Coronary Intervention Initially Treated With Prasugrel or Ticagrelor: Systematic Review and Meta-analysis

Objective: To evaluate the effects of switching from ticagrelor or prasugrel to clopidogrel in acute coronary syndrome (ACS) patients managed with percutaneous coronary intervention on major adverse cardiovascular events (MACEs) and bleeding. Data Sources: We searched MEDLINE, EMBASE, CENTRAL, bibliographies of relevant articles, and clinicaltrials.gov for eligible articles published from inception to January 27, 2019. Study Selection and Data Extraction: We included randomized controlled trials (RCTs) and cohort and case-control studies that reported on ≥1 outcome of interest. Primary outcomes were MACE and major bleeding, and the secondary outcome was any bleeding. Data Synthesis: From 483 articles, we included 7 relevant studies (2 RCTs, 5 cohort studies) at high/unclear risk of bias. Random-effects meta-analysis revealed inconclusive effects on MACE (hazard ratio [HR] = 1.00, 95% CI = 0.59-1.68; I² = 82%), major bleeding (HR = 0.51; 0.19-1.35; I² = 91%), and any bleeding (HR = 0.64; 0.38-1.07; I² = 85%). Similar nonsignificant results were obtained in secondary analyses evaluating risk ratios. Relevance to Patient Care and Clinical Practice: Ticagrelor and prasugrel, are now considered preferred therapy over clopidogrel in patients with ACS. Switching from these potent P2Y₁₂ inhibitors to clopidogrel is commonly performed to reduce bleeding risk, other adverse effects, or costs. Current best-available evidence is inconclusive regarding the effects of switching to clopidogrel on the risk of MACE and bleeding. Overall, studies were underpowered to detect clinically important differences. Conclusions: Until adequately powered trials demonstrate an advantage to switching to clopidogrel from prasugrel or ticagrelor, clinicians may consider this approach as clinically indicated on an individual, case-by-case basis.

Oral Antiplatelet Therapy for Secondary Prevention of Acute Coronary Syndrome

Patients surviving an acute coronary syndrome (ACS) remain at increased risk of ischemic events long term. This paper reviews current evidence and guidelines for oral antiplatelet therapy for secondary prevention following ACS, with respect to decreased risk of ischemic events versus bleeding risk according to individual patient characteristics and risk factors. Specifically, data are reviewed from clinical studies of clopidogrel, prasugrel, ticagrelor and vorapaxar, as well as the results of systematic reviews and meta-analyses looking at the benefits and risks of oral antiplatelet therapy, and the relative merits of shorter versus longer duration of dual antiplatelet therapy, in different patient groups.

De-Escalation of P2Y12 Receptor Inhibitor Therapy after Acute Coronary Syndromes in Patients Undergoing Percutaneous Coronary Intervention

Dual antiplatelet therapy (DAPT) - a combination of a P2Y₁₂ receptor inhibitor and aspirin - has revolutionized antithrombotic treatment. Potent P2Y₁₂ inhibitors such as prasugrel and ticagrelor exhibit a strong and more consistent platelet inhibition when compared to clopidogrel. Therefore, ticagrelor and prasugrel significantly reduce ischemic events, but at an expense of an increased bleeding risk in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI). These observations have engaged intensive clinical research in alternative DAPT regimens to achieve sufficient platelet inhibition with an acceptable bleeding risk. Our review focusses on P2Y₁₂ receptor therapy de-escalation defined as a switch from a potent antiplatelet agent (ticagrelor or prasugrel) to clopidogrel. Recently, both unguided (platelet function testing independent) and guided (platelet function testing dependent) DAPT de-escalation strategies have been investigated in different clinical studies and both switching strategies could be possible options to prevent bleeding complications without increasing ischemic risk. In light of the still limited data currently available, future large-scale trials should accumulate more data on various DAPT de-escalation regimens with both ticagrelor and prasugrel in unguided and guided de-escalation approaches. In the current review we aim at summarizing and discussing the current evidence on this still emerging topic in the field of antiplatelet treatment.

An update on the use of anticoagulant therapy in ST-segment elevation myocardial infarction

INTRODUCTION

Together with antiplatelet therapy, anticoagulants are vital to improve outcomes in patients presenting with ST-segment elevation myocardial infarction. Challenges lie in finding the optimal balance between the risk of bleeding and preventing thrombotic complications such as reinfarction or stent thrombosis. During the last decade, bivalirudin was introduced as a valid alternative to heparin for patients undergoing primary percutaneous coronary intervention. Several trials have been conducted to identify the agent with the best antithrombotic results at the lowest bleeding complication rate. In a rapidly evolving field with changes in vascular access, available P2Y₁₂ inhibitors, and indications for glycoprotein IIb/IIIa inhibitor administration, conflicting evidence became available.

AREAS COVERED

This paper mainly focuses on the evidence above and gives brief discussion to the recent literature on anticoagulation in fibrinolytic therapy and advances in antiplatelet therapy.

EXPERT OPINION

To date, no robust evidence is available challenging unfractionated heparin as the primary choice for anticoagulation in patients presenting with ST-segment elevation myocardial infarction. Further research should include efforts to refine anticoagulation strategies on an individual patient level. For patients undergoing primary percutaneous coronary intervention, bivalirudin could be used as an alternative to unfractionated heparin, while enoxaparin or fondaparinux is an alternative agent for patients treated with fibrinolytic therapy.