Reduction in Ischemic Events With Ticagrelor in Diabetic Patients With Prior Myocardial Infarction in PEGASUS-TIMI 54

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.

Design and baseline characteristics of the eValuation of ERTugliflozin effIcacy and Safety CardioVascular outcomes trial (VERTIS-CV)

BACKGROUND

Ertugliflozin is an inhibitor of sodium-glucose co-transporter-2 (SGLT2), approved in the United States and European Union to improve glycemic control in adults with type 2 diabetes mellitus (T2DM). The VERTIS cardiovascular (CV) outcomes trial (NCT01986881) has a primary objective to demonstrate non-inferiority of ertugliflozin versus placebo on major adverse CV events: time to the first event of CV death, nonfatal myocardial infarction, or nonfatal stroke. Secondary objectives are to demonstrate superiority of ertugliflozin versus placebo on time to: 1) the composite outcome of CV death or hospitalization for heart failure (HF); 2) CV death; and 3) the composite outcome of renal death, dialysis/transplant, or doubling of serum creatinine from baseline.

METHODS

Patients ≥40 years old with T2DM (HbA1c 7.0-10.5%) and established atherosclerotic cardiovascular disease (ASCVD) of the coronary, cerebral, and/or peripheral arterial systems, were randomized 1:1:1 to once daily double-blind placebo, ertugliflozin 5 mg or 15 mg added to existing therapy.

RESULTS

8246 patients were randomized and 8238 received at least 1 dose of investigational product. Mean age was 64.4 years, 11.0% were ≥75 years old, and mean diabetes duration was 12.9 years with screening HbA1c of 8.3%. At entry, coronary artery disease, cerebrovascular disease, and peripheral arterial disease were present in 76.3%, 23.1%, and 18.8% of patients, respectively. HF was present in 23.1%, and Stage 3 kidney disease in 21.6% of patients.

CONCLUSION

The results from the VERTIS-CV trial will define the CV and renal safety and efficacy of ertugliflozin in patients with T2DM and ASCVD.

Type-2 diabetes mellitus and cardiovascular disease

The global prevalence of diabetes has risen in adults from 4.7% in 1980 to 8.5% in 2014. 90–95% of adults with diabetes have Type 2 diabetes (T2D). This paper focuses on the diagnosis and treatment of T2D patients who have or are at risk for cardiovascular disease. Hyperglycemia, insulin resistance and excess fatty acids increase oxidative stress, disrupt protein kinase C signaling and increase advanced glycation end-products that result in vascular inflammation, vasoconstriction, thrombosis and atherogenesis. Intensive T2D treatment produces a ≥10% risk reduction in major macrovascular and microvascular events. Glucose-lowering therapies must be individualized. Metformin is an optimal drug for monotherapy. If hemoglobin A1c is not at goal, a sodium-glucose cotransporter-2 inhibitor or a dipeptidyl peptidase-4 inhibitor should be considered for therapy with metformin. Coronary angioplasty/stenting is recommended for diabetic patients with acute myocardial infarctions. Coronary artery bypass grafting is recommended for symptomatic diabetic patients with multivessel disease.

Diabetes and antiplatelet therapy: from bench to bedside

Diabetes mellitus (DM) is a metabolic disorder associated with accelerated atherogenesis and an increased risk of atherothrombotic complications. Multiple mechanisms contribute to the pro-thrombotic status which characterizes DM patients underscoring the importance of antiplatelet therapies used for secondary prevention in these patients. For many years, dual antiplatelet therapy (DAPT) with aspirin and the P2Y₁₂ inhibitor clopidogrel has represented the mainstay of treatment following an acute coronary syndrome (ACS) or in patients undergoing percutaneous coronary interventions (PCI). Although DAPT reduces the incidence of atherothrombotic recurrences, these rates remain high in DM patients underscoring the need for more efficacious therapies. Oral platelet P2Y₁₂ receptor inhibitors with enhanced potency, such as prasugrel and ticagrelor, as well as antiplatelet therapies such as vorapaxar inhibiting the thrombin-mediated platelet signaling pathway, constitute treatment opportunities for patients with DM and have shown to be associated with a greater reduction in ischemic recurrences, albeit at the cost of more bleeding. This article reviews currently available antiplatelet agents and delivers an update on the advances and drawbacks of these agents used for secondary prevention in DM patients experiencing an ACS or undergoing PCI.

A high glucose level is associated with decreased aspirin-mediated acetylation of platelet cyclooxygenase (COX)-1 at serine 529: A pilot study

Diabetes is a major risk factor for cardiovascular diseases. Although aspirin is considered a cornerstone of the prevention and treatment of atherothrombotic-related ischemic events, this antiplatelet drug appears to be less effective in patients with poorly controlled diabetes. It has been suggested that the glycation of platelet proteins plays a pivotal role in poor responsiveness to aspirin. However, a direct effect on the critical residue (serine 529, or Ser 529) of the catalytic pocket of cyclooxygenase 1 (COX-1) has never been demonstrated. This pilot study aimed to elucidate the impact of hyperglycaemia on aspirin acetylation of COX-1 using a targeted mass spectrometry approach. We observed that high glucose concentration had a direct impact on the level of acetylation of the COX-1 Ser 529 residue, whereas it's overall acetylation level remained unchanged. Moreover, the functional aspirin-induced inhibition of COX-1 was dose-dependently impaired as glucose concentrations increased. These in vitro findings were in line with data obtained using platelets from diabetic patients. These data provide new insights into the interplay between glucose and aspirin on platelet proteins and their effects on platelet COX-1. They also suggest a potential mechanistic explanation for the phenomenon of poor response to aspirin in diabetic patients. Data are available via ProteomeXchange with identifier PXD011204. SIGNIFICANCE: Deciphering the mutual interplay between glucose and aspirin-mediated acetylation on platelet COX-1, might be of great interest as there is still a lack of information of the mechanism underlying this process that may contribute to the less-than expected response of platelets to aspirin, often observed in diabetes.

Phaseolus vulgaris Exerts an Inhibitory Effect on Platelet Aggregation through AKT Dependent Way

The Phaseolus vulgaris (common bean), a worldwide vegetable of high consumption, can act as a nutritional supplement in the diet of oversized individuals to reduce weight. Studies have demonstrated the existence of molecules capable of inhibiting the breakdown of carbohydrates via inhibition of both α-amylases and glycosidases. Here, we describe a novel property of the Phaseolus vulgaris: inhibition of thrombotic cardiovascular events. Using assays to test platelet aggregation and secretion, and flow cytometry against the surface expression of P-Selectin. We show that bean extracts significantly reduced adenosine 5′-diphosphate and arachidonic acid induced-platelet aggregation. The mechanism underlying such effect appears to be mediated by AKT, since AKT hypo-phosphorylation decreases the “inside out” activation of platelets. In sum, our results support the hypothesis that common beans are nutritional ingredients that help reduce the risk of cardiovascular diseases associated with platelet hyper-reactivity.

Cardiovascular Disease and Risk Management: Review of the American Diabetes Association Standards of Medical Care in Diabetes 2018

DESCRIPTION

The American Diabetes Association (ADA) annually updates its Standards of Medical Care in Diabetes to provide clinicians, patients, researchers, payers, and other interested parties with evidence-based recommendations for the diagnosis and management of patients with diabetes.

METHODS

For the 2018 standards, the ADA Professional Practice Committee searched MEDLINE through November 2017 to add, clarify, or revise recommendations on the basis of new evidence. The committee rated the recommendations as A, B, or C depending on the quality of evidence or E for expert consensus or clinical experience. The standards were reviewed and approved by the Executive Committee of the ADA Board of Directors, which includes health care professionals, scientists, and laypersons. Feedback from the larger clinical community informed revisions.

RECOMMENDATIONS

This synopsis focuses on guidance relating to cardiovascular disease and risk management in nonpregnant adults with diabetes. Recommendations address diagnosis and treatment of cardiovascular risk factors (hypertension and dyslipidemia), aspirin use, screening for and treatment of coronary heart disease, and lifestyle interventions.

Consensus Document ANMCO/ANCE/ARCA/GICR-IACPR/GISE/SICOA: Long-term Antiplatelet Therapy in Patients with Coronary Artery Disease

Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 receptor inhibitor is the cornerstone of pharmacologic management of patients with acute coronary syndrome (ACS) and/or those receiving coronary stents. Long-term (>1 year) DAPT may further reduce the risk of stent thrombosis after a percutaneous coronary intervention (PCI) and may decrease the occurrence of non-stent-related ischaemic events in patients with ACS. Nevertheless, compared with aspirin alone, extended use of aspirin plus a P2Y12 receptor inhibitor may increase the risk of bleeding events that have been strongly linked to adverse outcomes including recurrent ischaemia, repeat hospitalisation and death. In the past years, multiple randomised trials have been published comparing the duration of DAPT after PCI and in ACS patients, investigating either a shorter or prolonged DAPT regimen. Although the current European Society of Cardiology guidelines provide a backup to individualised treatment, it appears to be difficult to identify the ideal patient profile which could safely reduce or prolong the DAPT duration in daily clinical practice. The aim of this consensus document is to review contemporary literature on optimal DAPT duration, and to guide clinicians in tailoring antiplatelet strategies in patients undergoing PCI or presenting with ACS.

Antiplatelet Therapy in Coronary Artery Disease: A Daunting Dilemma

Percutaneous coronary intervention (PCI) with stenting for the treatment of acute coronary syndrome (ACS) is the contemporary standard of care. Such treatment is followed by dual antiplatelet therapy (DAPT) comprising of aspirin and a P2Y12 inhibitor. The efficacy of this therapy has been well established but the optimal duration of DAPT remains elusive, and has thus far attracted a prodigious deal of scientific attention. The decision regarding DAPT duration can be clinically challenging in the modern era with the evolution of newer stents, more potent antiplatelet agents, and novel anticoagulant drugs in addition to an older patient population with multiple comorbidities. Major societal guidelines have emphasized comprehensive assessment of ischemic and bleeding risk, in turn recommending individualization of DAPT duration, thus encouraging "shared decision making". The following review is aimed at critically evaluating the available evidence to help make these crucial clinical decisions regarding duration of DAPT and triple therapy.

Antiplatelet and antithrombotic treatment for secondary prevention in ischaemic heart disease

Platelets play a key role in the pathogenesis of acute coronary syndromes and this is why antiplatelet drugs are essential, both in the acute phase and in the long-term follow-up in preventing recurrent myocardial infarction, stroke and cardiovascular death. Aspirin is the most used agent and still remains the first choice drug for lifelong administration in secondary prevention after myocardial infarction. Dual antiplatelet therapy, targeting more than one pathway of platelet activation, has significantly improved the outcome of patients with acute coronary syndromes despite an increased risk of bleeding complications. The aim of this article is to provide an overview of the evidence from randomized clinical trials with a focus on the best association between aspirin and a P2Y₁₂ inhibitor such as clopidogrel, prasugrel or ticagrelor, on the selection of the appropriate agent based on the revascularization strategy and on the optimal duration of such an intensive treatment. We will also provide the latest evidence regarding new antithrombotic agents, such as vorapaxar or low dose rivaroxaban, that could be associated with dual antiplatelet therapy in high risk patients with the aim of further reducing the rate of major ischaemic complications. Finally we will address the issue of patients presenting with atrial fibrillation and a concomitant acute coronary syndrome who frequently need a percutaneous coronary intervention, with a specific focus on the combination therapy of antiplatelet and anticoagulant agents and on the current recommendations of the guidelines.

Antiplatelet Therapy in Diabetes

Cardiovascular disease (CVD) is a significant cause of morbidity and mortality among patients with diabetes mellitus (DM). Increased platelet reactivity among patients with DM contributes to disproportionately high levels of atherothrombotic CVD. Consequently, there has been tremendous interest in exploring the role of antiplatelet therapies in DM to reduce the development of and frequency of future cardiovascular events.

Thrombosis and Vascular Inflammation in Diabetes: Mechanisms and Potential Therapeutic Targets

Cardiovascular disease remains the main cause of morbidity and mortality in patients with diabetes. The risk of vascular ischemia is increased in this population and outcome following an event is inferior compared to individuals with normal glucose metabolism. The reasons for the adverse vascular profile in diabetes are related to a combination of more extensive atherosclerotic disease coupled with an enhanced thrombotic environment. Long-term measures to halt the accelerated atherosclerotic process in diabetes have only partially addressed vascular pathology, while long-term antithrombotic management remains largely similar to individuals without diabetes. We address in this review the pathophysiological mechanisms responsible for atherosclerosis with special emphasis on diabetes-related pathways. We also cover the enhanced thrombotic milieu, characterized by increased platelet activation, raised activity of procoagulant proteins together with compromised function of the fibrinolytic system. Potential new therapeutic targets to reduce the risk of atherothrombosis in diabetes are explored, including alternative use of existing therapies. Special emphasis is placed on diabetes-specific therapeutic targets that have the potential to reduce vascular risk while keeping an acceptable clinical side effect profile. It is now generally acknowledged that diabetes is not a single clinical entity but a continuum of various stages of the condition with each having a different vascular risk. Therefore, we propose that future therapies aiming to reduce vascular risk in diabetes require a stratified approach with each group having a "stage-specific" vascular management strategy. This "individualized care" in diabetes may prove to be essential to improve vascular outcome in this high risk population.

9. Cardiovascular Disease and Risk Management: Standards of Medical Care in Diabetes-2018

The American Diabetes Association (ADA) "Standards of Medical Care in Diabetes" includes ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations, please refer to the Standards of Care Introduction Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.

Prevalence and predictors of dual antiplatelet therapy prolongation beyond one year in patients with acute coronary syndrome

There are limited real-world data on prevalence and predictors of dual antiplatelet therapy (DAPT) prolongation beyond one year after acute coronary syndrome (ACS). We have explored such issue in the START ANTIPLATELET Registry, which is a prospective, observational, multicenter, Italian registry performed in seven Italian cardiology institutions including patients admitted for ACS and followed up to one year. Out of a total population of 840 ACS patients, 596 patients had completed 12-month follow-up being on DAPT. Decision to prolong DAPT beyond one year was taken in 79 patients (13%), whereas in 517 patients DAPT was stopped. The strongest predictors of DAPT continuation were a new cardiovascular events after the index admission event (OR 3.3, 95% CI 1.4-7.7), no bleeding complications (OR 3.2, 95% CI 1.2-8.3) and no anemia during one-year follow-up (OR 2.6, 95% CI 1.1-5.9); other independent predictors were renal failure (OR 2.5, 95% CI 1.3-5.0) and peripheral artery disease (OR 1.8, 95% CI 1.1-3.0). The choice of DAPT prolongation was not correlated with younger ager, presence of diabetes mellitus, coronary angioplasty as initial treatment strategy or type of implanted stent (drug-eluting vs bare metal). In conclusion, this study provides a real-world snapshot on the factors influencing the option to continue DAPT beyond one year after ACS; a low bleeding risk seems to influence the choice to prolong DAPT more than a high ischemic risk.

Long-Term Use of Ticagrelor in Patients with Coronary Artery Disease

PURPOSE OF REVIEW

This review aims to summarize and discuss safety and effectiveness of the long-term use of ticagrelor in patients with coronary artery disease (CAD).

RECENT FINDINGS

Ticagrelor is an orally administered, direct, and reversible inhibitor of the P2Y₁₂-platelet receptor. Long-term use of ticagrelor in patients with previous myocardial infarction (MI) has been investigated in the PEGASUS-TIMI-54 trial. Overall, 21,162 patients with a spontaneous MI 1 to 3 years before randomization were randomly assigned to ticagrelor 90 mg bid, ticagrelor 60 mg bid, or placebo. Compared with placebo, both doses of ticagrelor showed that they were capable of significantly reducing the primary efficacy endpoint, although with a significant increase in TIMI major bleeding. Intracranial hemorrhage or fatal bleeding did not differ across groups. These findings establish clear benefit of DAPT extension with ticagrelor beyond 1 year of treatment, which comes with a tradeoff of clinically meaningful bleeding. Altogether, current evidence suggests that the duration of DAPT remains a patient-by-patient decision based on thrombotic and bleeding risk profiles.

Antiplatelet Agents for the Treatment and Prevention of Coronary Atherothrombosis

Antiplatelet drugs provide first-line antithrombotic therapy for the management of acute ischemic syndromes (both coronary and cerebrovascular) and for the prevention of their recurrence. Their role in the primary prevention of atherothrombosis remains controversial because of the uncertain balance of the potential benefits and risks when combined with other preventive strategies. The aim of this consensus document is to review the evidence for the efficacy and safety of antiplatelet drugs, and to provide practicing cardiologists with an updated instrument to guide their choice of the most appropriate antiplatelet strategy for the individual patient presenting with different clinical manifestations of coronary atherothrombosis, in light of comorbidities and/or interventional procedures.

Cost-Effectiveness of Long-Term Ticagrelor in Patients With Prior Myocardial Infarction: Results From the PEGASUS-TIMI 54 Trial

BACKGROUND

In patients with a myocardial infarction (MI) 1 to 3 years earlier, treatment with ticagrelor + low-dose aspirin (ASA) reduces the risk of cardiovascular (CV) death, MI, or stroke compared with low-dose aspirin alone, but at an increased risk of major bleeding.

OBJECTIVES

The authors evaluated cost-effectiveness of ticagrelor + low-dose ASA in patients with prior MI within the prior 3 years.

METHODS

The authors performed a prospective economic substudy alongside the PEGASUS-TIMI 54 (Prevention of Cardiovascular Events in Patients With Prior Heart Attack Using Ticagrelor Compared to Placebo on a Background of Aspirin-Thrombolysis In Myocardial Infarction 54) trial, which randomized 21,162 patients to ASA alone, ticagrelor 60 mg twice daily + low-dose ASA, or ticagrelor 90 mg twice daily + low-dose ASA. Medical resource use data were collected over a median 33-month follow-up. Costs were assessed from the U.S. health care system perspective. In-trial data relating to survival, utility, and costs were combined with lifetime projections to evaluate lifetime cost-effectiveness of the Food and Drug Administration-approved lower-dose ticagrelor regimen (60 mg twice daily).

RESULTS

Hospitalization costs were similar for ticagrelor 60 mg and placebo ($2,262 vs. $2,333; 95% confidence interval for difference -$303 to $163; p = 0.54); after inclusion of a daily ticagrelor 60 mg cost of $10.52, total costs were higher for ticagrelor ($10,016 vs. $2,333; 95% CI: $7,441 to $7,930; p < 0.001). In-trial quality-adjusted life-years (QALYs) were similar (2.28 vs. 2.27; p = 0.34). Over a lifetime horizon, ticagrelor was associated with QALY gains of 0.078 and incremental costs of $7,435, yielding an incremental cost-effectiveness ratio (ICER) of $94,917/QALY gained. Several high-risk groups had more favorable ICERs, including patients with >1 prior MI, multivessel disease, diabetes, renal dysfunction (all with ICERs $50,000 to $70,000/QALY gained), patients age <75 years (ICER = $44,779/QALY gained), and patients with peripheral artery disease (ICER = $13,427/QALY gained).

CONCLUSIONS

For patients with a history of MI >1 year previously, long-term treatment with ticagrelor 60 mg + low-dose ASA yields a cost-effectiveness ratio suggesting intermediate value based on current guidelines. Ticagrelor appears to provide higher value for patients in several recognized high-risk subgroups. (Prevention of Cardiovascular Events [e.g., Death From Heart or Vascular Disease, Heart Attack, or Stroke] in Patients With Prior Heart Attack Using Ticagrelor Compared to Placebo on a Background of Aspirin [PEGASUS]; NCT01225562).

Serial Measurement of High-Sensitivity Troponin I and Cardiovascular Outcomes in Patients With Type 2 Diabetes Mellitus in the EXAMINE Trial (Examination of Cardiovascular Outcomes With Alogliptin Versus Standard of Care)

Background:

We aimed to describe the relationship between changes in high-sensitivity cardiac troponin I (hsTnI) and cardiovascular outcomes.

Methods:

The EXAMINE trial (Examination of Cardiovascular Outcomes With Alogliptin Versus Standard of Care) was a phase IIIb clinical outcomes trial designed to evaluate the cardiovascular safety of alogliptin, a nonselective dipeptidyl peptidase 4 inhibitor. Patients with type 2 diabetes mellitus, glycohemoglobin between 6.5% and 11% (or between 7% and 11% if they were on insulin), and a recent acute coronary syndrome (between 15 and 90 days before randomization) were eligible for the trial. hsTnI was measured using the Abbott ARCHITECT assay at baseline and 6 months in patients randomized in the EXAMINE trial. This analysis was restricted to patients randomized ≥30 days after qualifying acute coronary syndrome to mitigate the potential for persistent hsTnI elevation after acute coronary syndrome (n=3808). The primary end point of the trial was cardiovascular death, myocardial infarction, or stroke. Cardiovascular death or heart failure was a prespecified, adjudicated secondary end point.

Results:

At baseline, hsTnI was detectable (≥1.9 ng/L) in 93% of patients and >99 th percentile upper reference limit in 16%. There was a strong relationship between increasing hsTnI, both at baseline and 6 months, and the incidence of cardiovascular events through 24 months ( P <0.001 for each). Patients with undetectable hsTnI at baseline and 6 months were at the lowest risk of future cardiovascular events. Stable patients with hsTnI ≥99th percentile upper reference limit at 6 months were at increased risk of cardiovascular death, myocardial infarction, or stroke compared with patients with hsTnI <99 percentile upper reference limit irrespective of whether hsTnI was newly elevated (28.1% versus 8.8%; adjusted hazard ratio, 2.65; 95% confidence interval, 1.64–4.28; P <0.001) or persistently so (22.5% versus 8.8%; adjusted hazard ratio, 1.90; 95% confidence interval, 1.33–2.70; P <0.001). Alogliptin neither increased nor decreased the risk of cardiovascular events compared with placebo in patients with high baseline hsTnI (22.3% versus 23.0%; hazard ratio, 0.87; 95% confidence interval, 0.60–1.25; P =0.44).

Conclusions:

Serial assessment of hsTnI revealed a substantial proportion of patients with type 2 diabetes mellitus without clinically recognized events had dynamic or persistently elevated values and were at high risk of recurrent events. hsTnI may have a role in personalizing preventive strategies in patients with diabetes mellitus based on risk.

Clinical Trial Registration:

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00968708.

Impact of Diabetes Mellitus on the Pharmacodynamic Effects of Ticagrelor Versus Clopidogrel in Troponin-Negative Acute Coronary Syndrome Patients Undergoing Ad Hoc Percutaneous Coronary Intervention

Background

Diabetes mellitus (DM) is associated with enhanced platelet reactivity and impaired response to oral antiplatelet therapy, including clopidogrel. This post hoc analysis investigated the pharmacodynamic effects of ticagrelor versus clopidogrel loading dose (LD) in troponin‐negative acute coronary syndrome patients with or without DM undergoing percutaneous coronary intervention in the Ad Hoc PCI study.

Methods and Results

Patients randomized (1:1) to receive ticagrelor 180 mg LD or clopidogrel 600 mg LD were assessed by diabetic status. Platelet reactivity (P2Y₁₂ reaction units [PRU] on VerifyNow^® assay) was measured pre‐LD, at 0.5, 2, and 8 hours post‐LD, and at the end of the percutaneous coronary intervention. The primary endpoint was PRU levels 2 hours post‐LD; secondary endpoints included rates of high on‐treatment platelet reactivity (PRU≥208). Of 100 randomized patients, 51 received ticagrelor (DM, n=20; non‐DM, n=31) and 49 clopidogrel (DM, n=16; non‐DM, n=33). At 2 hours post‐LD, mean (SD) PRU levels in DM patients were 130.1 (111.7) with ticagrelor versus 287.6 (71.9) with clopidogrel (mean [95%CI] difference −157.5 [−225.3, −89.8]; P<0.001); in non‐DM patients, they were 75.3 (75.7) versus 243.0 (72.4) (mean difference −167.7 [−207.1, −128.3]; P<0.001). High on‐treatment platelet reactivity rates at 2 hours post‐LD were also significantly (P<0.001) reduced with ticagrelor versus clopidogrel in DM and non‐DM patients. Between‐treatment differences for PRU and high on‐treatment platelet reactivity were not significant at earlier time points but were at 8 hours post‐LD (P<0.001).

Conclusions

Compared with clopidogrel, ticagrelor achieved faster, enhanced platelet inhibition and reduced high on‐treatment platelet reactivity rates, in DM and non‐DM patients.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01603082.

Consistent platelet inhibition with ticagrelor 60 mg twice-daily following myocardial infarction regardless of diabetes status

Diabetes increases cardiovascular risk and reduces pharmacodynamic response to some oral antiplatelet drugs. This study aimed to determine whether ticagrelor 60 mg twice daily (bid) provided potent and consistent platelet inhibition in patients with vs without diabetes in the PEGASUS-TIMI 54 platelet function substudy. Out of 180 patients studied, 58 patients were randomised to and had received at least four weeks of ticagrelor 60 mg bid, with 20 (34 %) having diabetes, 58 patients received ticagrelor 90 mg bid, with 12 (21 %) having diabetes, and 64 patients received placebo, with 18 (28 %) having diabetes. Blood was sampled pre- and 2 hours post-maintenance dose. In patients treated with ticagrelor 60 mg bid, on-treatment platelet reactivity to ADP, as determined by light transmission aggregometry (LTA), VerifyNow and VASP, was similar in patients with vs without diabetes (LTA post-dose, ADP 20 µM: 29 ± 14 vs 34 ± 10 %, respectively; p = 0.19). A consistent inhibitory effect of ticagrelor 60 mg bid was observed pre- and post-dose regardless of diabetes status, even in insulin-treated patients. Patients with diabetes did not have an increased incidence of high platelet reactivity in either ticagrelor group. Platelet reactivity was similar in patients with diabetes treated with ticagrelor 60 mg vs 90 mg bid. Pharmacokinetics of ticagrelor were not affected by diabetes status. In conclusion, ticagrelor 60 mg bid is equally effective at reducing platelet reactivity in patients with and without diabetes, yielding a consistently high level of platelet inhibition regardless of diabetes status.

Optimal duration of dual anti-platelet therapy after percutaneous coronary intervention: 2016 consensus position of the Italian Society of Cardiology

Definition of the optimal duration of dual anti-platelet therapy (DAPT) is an important clinical issue, given the large number of patients having percutaneous coronary intervention (PCI), the costs and risks of pharmacologic therapy, the consequences of stent thrombosis, and the potential benefits of DAPT in preventing ischaemic outcomes beyond stent thrombosis. Nowadays, the rationale for a prolonged duration of DAPT should be not only the prevention of stent thrombosis, but also the prevention of ischaemic events unrelated to the coronary stenosis treated with index PCI. A higher predisposition to athero-thrombosis may persist for years after an acute myocardial infarction, and even stable patients with a history of prior myocardial infarction are at high risk for major adverse cardiovascular events. Recently, results of pre-specified post-hoc analyses of randomized clinical trials, including the PEGASUS-TIMI 54 trial, have shed light on strategies of DAPT in various clinical situations, and should impact the next rounds of international guidelines, and also routine practice. Accordingly, the 2015 to 2016 the Board of the Italian Society of Cardiology addressed newer recommendations on duration of DAPT based on most recent scientific information. The document states that physicians should decide duration of DAPT on an individual basis, taking into account ischaemic and bleeding risks of any given patient. Indeed, current controversy surrounding optimal duration of DAPT clearly reflects the fact that, nowadays, a one size fits all strategy cannot be reliably applied to patients treated with PCI. Indeed, patients usually have factors for both increased ischaemic and bleeding risks that must be carefully evaluated to assess the benefit/risk ratio of prolonged DAPT. Personalized management of DAPT must be seen as a dynamic prescription with regular re-evaluations of the risk/benefit to the patient according to changes in his/her clinical profile. Also, in order to derive more benefit than harm from new treatments, a multi-parametric approach using several risk scores of the ischaemic and bleeding risks might improve the process of risk factor characterization. In patients with high ischaemic risk, particularly those with a history of myocardial infarction, the benefits of extended DAPT (particularly with ticagrelor up to 3 years) are likely to outweigh the risks.

Antiplatelet Therapy for Secondary Prevention After Acute Myocardial Infarction

Patients with prior myocardial infarction (MI) are at long-term heightened risk for recurrent ischemic events. Several large randomized controlled trials have demonstrated the benefit of more intensive antiplatelet strategies for long-term secondary prevention of cardiovascular death, recurrent MI, and stroke in patients with a history of MI at a cost of increased bleeding. The bleeding risk associated with long-term intensive antiplatelet strategies requires careful patient selection and involvement of patients in shared decision making regarding risks and benefits of therapy. Clinical characteristics, adherence to therapy, and integrated risk scores may aid clinicians in translating clinical trials into individualized therapy.

Optimal Duration of Dual Antiplatelet Therapy After Percutaneous Coronary Intervention

Dual antiplatelet therapy (DAPT) is an essential component of treatment in patients with coronary artery disease treated with percutaneous coronary intervention (PCI). Recommendations for duration of DAPT after PCI should consider patient-specific risk, clinical presentation, stent characteristics, and procedural factors. Prolonged DAPT results in a reduction of stent thrombosis (ST) and myocardial infarction (MI) at the cost of increased bleeding. Studies of shorter-duration DAPT demonstrate similar mortality, MI, ST, and less bleeding when compared with longer DAPT duration. We review current evidence for strategies of prolonged DAPT and abbreviated DAPT following PCI.

Extended dual antiplatelet therapy after acute coronary syndrome in Spain: Results from the EPICOR study

INTRODUCTION

Real-world, country-specific studies of dual antiplatelet therapy (DAPT) duration among survivors of acute coronary syndrome (ACS) are important for improving long-term prognosis.

AIMS

To investigate DAPT duration after hospital discharge for ACS in Spain.

RESULTS

Data from patients enrolled in the Spanish cohort of the EPICOR (long-tErm follow-up of antithrombotic management Patterns In acute CORonary syndrome patients) study (NCT01171404) were analyzed for changes to antithrombotic medication up to 2 years postdischarge according to index event diagnosis and patient characteristics. Deaths, coronary events, and bleeding events were analyzed over the same period. Overall, a high proportion of patients remained on DAPT at 2 years (53.1%). Among patients who experienced any on-treatment bleeding event, almost two-thirds remained on DAPT at the end of follow-up. Patients >65 years, diabetic, or those that were medically managed were more likely to continue with DAPT until 2 years following discharge. At 2 years, the incidence of bleeding events requiring hospitalization was low compared with the incidence of coronary events (1.4% vs 6.6%). There was a numerical reduction in coronary events, but no increase in bleeding events, with DAPT continuation compared with single antiplatelet therapy.

CONCLUSIONS

More than half of patients in this unselected cohort study remained on DAPT at 2 years following discharge for ACS. Continuation with DAPT was greater among patients with additional cardiovascular risk factors, which suggests that treating physicians in Spain prioritizes ischemic risk reduction over bleeding risk in patients with ACS, according to patient's risk profile.

Short term versus long term dual antiplatelet therapy after implantation of drug eluting stent in patients with or without diabetes: systematic review and meta-analysis of individual participant data from randomised trials

OBJECTIVE

 To compare clinical outcomes between short term (up to 6 months) and long term (12 months) dual antiplatelet therapy (DAPT) after placement of a drug eluting stent in patients with and without diabetes.

DESIGN

 Individual participant data meta-analysis. Cox proportional regression models stratified by trial were used to assess the impact of diabetes on outcomes.

DATA SOURCE

 Medline, Embase, and Cochrane databases and proceedings of international meetings searched for randomised controlled trials comparing durations of DAPT after placement of a drug eluting stent. Individual patient data pooled from six DAPT trials.

PRIMARY OUTCOME

 Primary study outcome was one year risk of major adverse cardiac events (MACE), defined as cardiac death, myocardial infarction, or definite/probable stent thrombosis. All analyses were conducted by intention to treat.

RESULTS

 Six trials including 11 473 randomised patients were pooled. Of these patients, 3681 (32.1%) had diabetes and 7708 (67.2%) did not (mean age 63.7 (SD 9.9) and 62.8 (SD 10.1), respectively), and in 84 (0.7%) the information was missing. Diabetes was an independent predictor of MACE (hazard ratio 2.30, 95% confidence interval 1.01 to 5.27; P=0.048 At one year follow-up, long term DAPT was not associated with a decreased risk of MACE compared with short term DAPT in patients with (1.05, 0.62 to 1.76; P=0.86) or without (0.97, 0.67 to 1.39; P=0.85) diabetes (P=0.33 for interaction). The risk of myocardial infarction did not differ between the two DAPT regimens (0.95, 0.58 to 1.54; P=0.82; for those with diabetes and 1.15, 0.68 to 1.94; P=0.60; for those without diabetes (P=0.84 for interaction). There was a lower risk of definite/probable stent thrombosis with long term DAPT among patients with (0.26, 0.09 to 0.80; P=0.02) than without (1.42, 0.68 to 2.98; P=0.35) diabetes, with positive interaction testing (P=0.04 for interaction), although the landmark analysis showed a trend towards benefit in both groups. Long term DAPT was associated with higher rates of major or minor bleeding, irrespective of diabetes (P=0.37 for interaction).

CONCLUSIONS

 Although the presence of diabetes emerged as an independent predictor of MACE after implantation of a drug eluting stent, compared with short term DAPT, long term DAPT did not reduce the risk of MACE but increased the risk of bleeding among patients with stents with and without diabetes.

Protective Effects of Ticagrelor on Myocardial Injury After Infarction

BACKGROUND

The P2Y₁₂ receptor antagonist ticagrelor has been shown to be clinically superior to clopidogrel. Although the underlying mechanisms remain elusive, ticagrelor may exert off-target effects through adenosine-related mechanisms. We aimed to investigate whether ticagrelor reduces myocardial injury to a greater extent than clopidogrel after myocardial infarction (MI) at a similar level of platelet inhibition and to determine the underlying mechanisms.

METHODS

Pigs received the following before MI induction: (1) placebo-control; (2) a loading dose of clopidogrel (600 mg); (3) a loading dose of ticagrelor (180 mg); or (4) a loading dose of ticagrelor followed by an adenosine A1/A2-receptor antagonist [8-(p-sulfophenyl)theophylline, 4 mg/kg intravenous] to determine the potential contribution of adenosine in ticagrelor-related cardioprotection. Animals received the corresponding maintenance doses of the antiplatelet agents during the following 24 hours and underwent 3T-cardiac MRI analysis. Platelet inhibition was monitored by ADP-induced platelet aggregation. In the myocardium, we assessed the expression and activation of proteins known to modulate edema formation, including aquaporin-4 and AMP-activated protein kinase and its downstream effectors CD36 and endothelial nitric oxide synthase and cyclooxygenase-2 activity.

RESULTS

Clopidogrel and ticagrelor exerted a high and consistent antiplatelet effect (68.2% and 62.2% of platelet inhibition, respectively, on challenge with 20 μmol/L ADP) that persisted up to 24 hours post-MI (P<0.05). All groups showed comparable myocardial area-at-risk and cardiac worsening after MI induction. 3T-Cardiac MRI analysis revealed that clopidogrel- and ticagrelor-treated animals had a significantly smaller extent of MI than placebo-control animals (15.7 g left ventricle and 12.0 g left ventricle versus 22.8 g left ventricle, respectively). Yet, ticagrelor reduced infarct size to a significantly greater extent than clopidogrel (further 23.5% reduction; P=0.0026), an effect supported by troponin-I assessment and histopathologic analysis (P=0.0021). Furthermore, in comparison with clopidogrel, ticagrelor significantly diminished myocardial edema by 24.5% (P=0.004), which correlated with infarct mass (r=0.73; P<0.001). 8-(p-Sulfophenyl)theophylline administration abolished the cardioprotective effects of ticagrelor over clopidogrel. At a molecular level, aquaporin-4 expression decreased and the expression and activation of AMP-activated protein kinase signaling and cyclooxygenase-2 increased in the ischemic myocardium of ticagrelor- versus clopidogrel-treated animals (P<0.05). These protein changes were not observed in those animals administered the adenosine receptor blocker 8-(p-sulfophenyl)theophylline.

CONCLUSIONS

Ticagrelor, beyond its antiplatelet efficacy, exerts cardioprotective effects by reducing necrotic injury and edema formation via adenosine-dependent mechanisms.

Pharmacodynamic Comparison of Prasugrel Versus Ticagrelor in Patients With Type 2 Diabetes Mellitus and Coronary Artery Disease: The OPTIMUS (Optimizing Antiplatelet Therapy in Diabetes Mellitus)-4 Study

BACKGROUND

Patients with diabetes mellitus (DM) are at increased risk of atherothrombotic events, underscoring the importance of effective platelet inhibiting therapies. Prasugrel and ticagrelor reduce thrombotic complications to a greater extent than clopidogrel. Subgroup analyses of pivotal clinical trials testing prasugrel and ticagrelor versus clopidogrel showed DM patients to have benefits that were consistent with the overall trial populations, although the magnitude of the ischemic risk reduction appeared to be enhanced with prasugrel. Whether these findings may be attributed to differences in the pharmacodynamic profiles of these drugs in DM patients remains poorly explored and represented the aim of this study.

METHODS

In this prospective, randomized, double-blind, double-dummy, crossover pharmacodynamic study, aspirin-treated DM patients (n=50) with coronary artery disease were randomly assigned to receive prasugrel (60 mg loading dose [LD]/10 mg maintenance dose once daily) or ticagrelor (180 mg LD/90 mg maintenance dose twice daily) for 1 week. Pharmacodynamic assessments were conducted using 4 different assays, including VerifyNow P2Y12, vasodilator-stimulated phosphoprotein, light transmittance aggregometry, and Multiplate, which allowed us to explore ADP- and non-ADP-induced (arachidonic acid-, collagen-, thrombin receptor-activating, peptide-induced) platelet signaling pathways. The acute (baseline, 30 minutes, and 2 hours post-LD) and maintenance (1 week) effects of therapy were assessed. The primary end point of the study was the comparison of P2Y12 reaction units determined by VerifyNow P2Y12 at 1 week between prasugrel and ticagrelor.

RESULTS

ADP- and non-ADP-induced measures of platelet reactivity reduced significantly with both prasugrel and ticagrelor LD and maintenance dose. P2Y12 reaction units defined by VerifyNow were similar between prasugrel and ticagrelor at 30 minutes and 2 hours post-LD. At 1 week, P2Y12 reaction units were significantly lower with ticagrelor than with prasugrel (52 [32-72] versus 83 [63-103]; least-square means difference: -31; 95% confidence interval, -57 to -4; P=0.022; primary end point). Pharmacodynamic assessments measured by vasodilator-stimulated phosphoprotein, light transmittance aggregometry, and Multiplate were similar between prasugrel and ticagrelor at each time point, including at 1 week. Rates of high on-treatment platelet reactivity were similar between groups with all assays at all time points.

CONCLUSIONS

In DM patients with coronary artery disease, ticagrelor exerts similar or greater inhibition of ADP-induced platelet reactivity in comparison with prasugrel in the acute and chronic phases of treatment, whereas the inhibition of measures of non-ADP-induced platelet reactivity was not significantly different between the 2 agents.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01852214.