Relationship Between Platelet Reactivity and Ischemic and Bleeding Events After Percutaneous Coronary Intervention in East Asian Patients: 1-Year Results of the PENDULUM Registry

Association of Age- and Body Mass Index-Stratified High On-Treatment Platelet Reactivity With Coronary Intervention Outcomes in East Asian Patients

BACKGROUND

Although age and body mass index (BMI) significantly affect platelet reactivity units and clinical outcomes after percutaneous coronary intervention, there are limited data on the relationship between high on-treatment platelet reactivity (HPR) and clinical outcomes on age and BMI differences. Thus, we investigated the association of HPR with clinical outcomes according to age and BMI.

METHODS AND RESULTS

The study analyzed 11 714 patients who underwent platelet function tests after percutaneous coronary intervention. The primary end point was the occurrence of major adverse cardiac and cerebrovascular events (MACCEs), whereas the secondary end point was major bleeding. HPR was defined as platelet reactivity units ≥252. Patients were categorized by age (<67 years of age or ≥67 years of age) and BMI (≤22.6 kg/m2 or >22.6 kg/m2). Patients <67 years of age with HPR had increases in both MACCEs (adjusted hazard ratio [HR], 1.436 [95% CI, 1.106-1.867]; P=0.007) and major bleeding (adjusted HR, 1.584 [95% CI, 1.095-2.290]; P=0.015) compared with the those with non-HPR, respectively. In patients ≥67 years of age with HPR, there were no differences in MACCEs, but there was a decrease in major bleeding (adjusted HR, 0.721 [95% CI, 0.542-0.959]; P=0.024). Meanwhile, patients with HPR with BMI >22.6 kg/m2 had increases in MACCEs (adjusted HR, 1.387 [95% CI, 1.140-1.688]; P=0.001). No differences were shown in major bleeding.

CONCLUSIONS

HPR was linked to an increase in MACCEs or a decrease in major bleeding in patients after percutaneous coronary intervention, depending on age and BMI. This study is the first to observe that clinical outcomes in patients with HPR after percutaneous coronary intervention may vary based on age and BMI. Because the study is observational, the results should be viewed as hypothesis generating and emphasize the need for randomized clinical trials.

Understanding Antithrombotic Agents for Rehabilitation Therapy: A Comprehensive Narrative Review

In rehabilitation medicine, attention must be paid to the medication. Among them, antithrombotic drugs are used for the initial treatment and secondary prevention of stroke, so as a basic knowledge, the pharmacological actions, characteristics, indications, and precautions for the use of antithrombotic drugs should be known. Antithrombotic agents are divided into antiplatelet agents and anticoagulants, and the appropriate antithrombotic agent is selected according to the main disease or condition. Antiplatelet agents include aspirin, clopidogrel, ticlopidine, prasugrel, ticagrelor, and cilostazol. Each antiplatelet agent has a different mechanism of action, characteristics, and indications, and should be prescribed with due consideration. Anticoagulants include heparin, synthetic Xa inhibitors, direct oral anticoagulants (DOACs), synthetic antithrombin agents, and warfarin. Knowledge of the mechanism of action, characteristics, and indications of each anticoagulant is necessary, as well as monitoring and dose adjustment. With regard to ischemic cerebrovascular disease (ICD) and antithrombotic agents, the first step is to classify cerebral infarction and to determine whether antiplatelet agents or anticoagulants should be used. Bleeding and recurrence prevention are important considerations in the selection of appropriate antithrombotic agents for the pathophysiology of ICD.

An Aspirin-Free Versus Dual Antiplatelet Strategy for Coronary Stenting: STOPDAPT-3 Randomized Trial

BACKGROUND

Bleeding rates on dual antiplatelet therapy (DAPT) within 1 month after percutaneous coronary intervention (PCI) remain high in clinical practice, particularly in patients with acute coronary syndrome or high bleeding risk. Aspirin-free strategy might result in lower bleeding early after PCI without increasing cardiovascular events, but its efficacy and safety have not yet been proven in randomized trials.

METHODS

We randomly assigned 6002 patients with acute coronary syndrome or high bleeding risk just before PCI either to prasugrel (3.75 mg/day) monotherapy or to DAPT with aspirin (81-100 mg/day) and prasugrel (3.75 mg/day) after loading of 20 mg of prasugrel in both groups. The coprimary end points were major bleeding (Bleeding Academic Research Consortium 3 or 5) for superiority and cardiovascular events (a composite of cardiovascular death, myocardial infarction, definite stent thrombosis, or ischemic stroke) for noninferiority with a relative 50% margin.

RESULTS

The full analysis set population consisted of 5966 patients (no-aspirin group, 2984 patients; DAPT group, 2982 patients; age, 71.6±11.7 years; men, 76.6%; acute coronary syndrome, 75.0%). Within 7 days before randomization, aspirin alone, aspirin with P2Y12 inhibitor, oral anticoagulants, and intravenous heparin infusion were given in 21.3%, 6.4%, 8.9%, and 24.5%, respectively. Adherence to the protocol-specified antiplatelet therapy was 88% in both groups at 1 month. At 1 month, the no-aspirin group was not superior to the DAPT group for the coprimary bleeding end point (4.47% and 4.71%; hazard ratio, 0.95 [95% CI, 0.75-1.20]; Psuperiority=0.66). The no-aspirin group was noninferior to the DAPT group for the coprimary cardiovascular end point (4.12% and 3.69%; hazard ratio, 1.12 [95% CI, 0.87-1.45]; Pnoninferiority=0.01). There was no difference in net adverse clinical outcomes and each component of coprimary cardiovascular end point. There was an excess of any unplanned coronary revascularization (1.05% and 0.57%; hazard ratio, 1.83 [95%CI, 1.01-3.30]) and subacute definite or probable stent thrombosis (0.58% and 0.17%; hazard ratio, 3.40 [95% CI, 1.26-9.23]) in the no-aspirin group compared with the DAPT group.

CONCLUSIONS

The aspirin-free strategy using low-dose prasugrel compared with the DAPT strategy failed to attest superiority for major bleeding within 1 month after PCI but was noninferior for cardiovascular events within 1 month after PCI. However, the aspirin-free strategy was associated with a signal suggesting an excess of coronary events.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04609111.

The prevalence of bleeding after percutaneous coronary interventions: A systematic review and meta-analysis

BACKGROUND

Bleeding is a common complication associated with percutaneous coronary intervention (PCI). The aim of this study was to determine the prevalence of bleeding after PCI through a systematic review and meta-analysis.

METHODS

The systematic review and meta-analysis covered the period from 1989 to 2023. Multiple databases, including Embase, PubMed, Scopus, Web of Sciences (WoS), MagIran, Scientific Information Database (SID), and Google Scholar, were searched using validated keywords with MeSH and Emtree. The I2 index was used to check for heterogeneity among studies.

RESULTS

The review of 8 studies, with a sample size of 397,298 participants, showed high heterogeneity (I2: 97.8 %). Therefore, the random effects method was used to analyze the results. The prevalence of bleeding after intervention in percutaneous coronary arteries was reported to be 4.4 % (95%CI: 2-9.1).

CONCLUSION

This meta-analysis showed a significant prevalence of bleeding after PCI, highlighting the need for health policymakers to pay more attention to the complications associated with PCI. Interventional cardiologists should consider the effective factors in these bleeding and how to treat and control them due to the importance of this complication.

Differential Impact of Clinical Factors for Predicting High Platelet Reactivity on Clinical Outcomes in Acute Myocardial Infarction Patients Treated With Clopidogrel and Prasugrel

AIMS

Several scoring systems, including the ABCD-GENE and HHD-GENE scores incorporating clinical and genetic factors, have been developed to identify patients likely to have high platelet reactivity on P2Y12 inhibitors, leading to increased risks of ischemic events. However, genetic testing is not widely available in daily practice. We aimed to evaluate the differential impact of clinical factors in the scores on ischemic outcomes in patients treated with clopidogrel and prasugrel.

METHODS

This bi-center registry included 789 patients with acute myocardial infarction (MI) undergoing percutaneous coronary intervention and treated with either clopidogrel or prasugrel at discharge. The relations of the number of clinical factors included in the ABCD-GENE (age ≥ 75 years, body mass index ＞30 kg/m2, chronic kidney disease, and diabetes) and HHD-GENE (hypertension, hemodialysis, and diabetes) scores to the primary endpoint of major cardiovascular events after discharge, a composite of death, recurrent MI, and ischemic stroke, were evaluated.

RESULTS

The number of clinical factors in the ABCD-GENE score was not predictive of ischemic outcomes after discharge in patients treated with clopidogrel and/or prasugrel, while the increase in the number of clinical factors of the HHD-GENE score was associated with an increased risk of the primary endpoint in a stepwise manner in patients on a P2Y12 inhibitor.

CONCLUSIONS

Clinical factors listed in the HHD-GENE score may help stratify ischemic risks in patients with acute MI treated with clopidogrel and prasugrel, whereas risk stratification without genetic testing in patients treated with clopidogrel may be challenging.

Time-dependent changes in P2Y12 reaction unit values for predicting the different types of cardiovascular events in patients with ischemic heart disease

Several studies have investigated the association between P2Y12 reaction unit (PRU) value and major adverse cardiovascular events (MACEs) in patients with ischemic heart disease, but there is no well-established consensus on the utility of PRU value. Furthermore, the optimal PRU cut-off value varied with studies. One reason may be that the endpoints and observation periods differed, depending on the study. This study aimed to investigate the optimal cut-off and predictive ability of the PRU value for predicting cardiovascular events, while considering different endpoints and observation periods. We surveyed a total of 338 patients receiving P2Y12 inhibitors and measured PRU during cardiac catheterization. Using time-dependent receiver operating characteristic analysis, we evaluated the cut-off and area under curve (AUC) of the PRU value for two MACEs (MACE ①: composite of death, myocardial infarction, stent thrombosis, and cerebral infarction; MACE ②: composite of MACE ① and target vessel revascularization) at 6, 12, 24 and 36 months after cardiac catheterization. MACE ① occurred in 18 cases and MACE ② in 32 cases. The PRU cut-off values at 6, 12, 24, and 36 months were 257, 238, 217, and 216, respectively, for MACE ① and 250, 238, 209, and 204, respectively, for MACE ②. The AUCs at 6, 12, 24, and 36 months were 0.753, 0.832, 0.718, and 0.717, respectively, for MACE ① and 0.724, 0.722, 0.664, and 0.682, respectively, for MACE ②. The optimal cut-off and predictive ability of PRU values for cardiovascular events varied depending on different endpoints and duration of the observation periods. A relatively high PRU value is effective for short-term event suppression, but a low value is required for long-term event suppression.

Current concepts and novel targets for antiplatelet therapy

Platelets have a crucial role in haemostasis and atherothrombosis. Pharmacological control of platelet hyper-reactivity has become a cornerstone in the prevention of thrombo-ischaemic complications in atherosclerotic diseases. Current antiplatelet therapies substantially improve clinical outcomes in patients with coronary artery disease, but at the cost of increased risk of bleeding. Beyond their role in thrombosis, platelets are known to regulate inflammatory (thrombo-inflammatory) and microcirculatory pathways. Therefore, controlling platelet hyper-reactivity might have implications for both tissue inflammation (myocardial ischaemia) and vascular inflammation (vulnerable plaque formation) to prevent atherosclerosis. In this Review, we summarize the pathophysiological role of platelets in acute myocardial ischaemia, vascular inflammation and atherosclerotic progression. Furthermore, we highlight current clinical concepts of antiplatelet therapy that have contributed to improving patient care and have facilitated more individualized therapy. Finally, we discuss novel therapeutic targets and compounds for antiplatelet therapy that are currently in preclinical development, some of which have a more favourable safety profile than currently approved drugs with regard to bleeding risk. These novel antiplatelet targets might offer new strategies to treat cardiovascular disease.

Impact of intravascular ultrasound parameters and platelet reactivity on primary patency after drug-coated balloon angioplasty for femoropopliteal artery disease

Although the superiority of DCBs to uncoated balloon angioplasty for the treatment of femoropopliteal (FP) lesions has been demonstrated, the association of clinical factors, including anatomical features evaluated by intravascular ultrasound (IVUS) and platelet reactivity, with the loss of patency has not been systematically studied. The current prospective, observational study enrolled 160 consecutive patients (male 67.5%, mean age 74.7 ± 9.7 years) with 213 FP lesions treated with DCBs under IVUS evaluation. The platelet reactivity was measured in P2Y12 reaction units for all of the patients at the DCB treatment. The primary end point was primary patency at 12 months, while the secondary end points were freedom from target lesion revascularization (TLR), all-cause death, major target limb amputation and bleeding events at 12 months. Mean lesion length was 11.9 ± 9.4 cm and 34 (16.0%) were chronic total occlusions (CTOs). Thirty-four (16.0%) were severely calcified lesions. Primary patency by Kaplan-Meier estimate was 79.2% at 12 months, while the 12-month freedom from TLR, all-cause death and bleeding events were observed in 89.1%, 93.4% and 97.4%, respectively. There were no major target limb amputations through 12 months. Multivariate analysis showed that subintimal angioplasty for CTO lesions was a sole risk factor for loss of 12-month primary patency, while other IVUS parameters and platelet reactivity were not.

Reduced-dose prasugrel monotherapy without aspirin after PCI with the SYNERGY stent in East Asian patients presenting with chronic coronary syndromes or non-ST-elevation acute coronary syndromes: rationale and design of the ASET Japan pilot study

The Acetyl Salicylic Elimination Trial (ASET) Japan pilot study is a multicentre, single-arm, open-label, proof-of-concept study with a stopping rule based on the occurrence of definite stent thrombosis. This study aims to demonstrate the feasibility and safety of low-dose prasugrel monotherapy following percutaneous coronary intervention (PCI) in Japanese patients presenting with chronic coronary syndromes (CCS) or non-ST-elevation acute coronary syndromes (NSTE-ACS). Four hundred patients with a SYNTAX score <23 requiring PCI due to CCS or NSTE-ACS will be screened and considered eligible for the study. The enrolment is planned in two phases: 1) 200 patients presenting with CCS, followed by 2) 200 patients presenting with NSTE-ACS. After optimal PCI with implantation of a SYNERGY (Boston Scientific) stent, patients will be enrolled and loaded with prasugrel 20 mg, followed by a maintenance dose of prasugrel 3.75 mg once daily without aspirin continued for 3 months in Phase 1 (CCS patients), and for 12 months in Phase 2 (NSTE-ACS patients). After these follow-up periods, prasugrel will be replaced by standard antiplatelet therapy according to local practice. The primary endpoint is a composite of cardiac death, target vessel myocardial infarction, or definite stent thrombosis after the index procedure. The primary bleeding endpoint is any Bleeding Academic Research Consortium type 3 or 5 bleeding occurring within 3 months of the index PCI for CCS patients, or 12 months for NSTE-ACS patients. The ASET Japan study is designed to demonstrate the feasibility and safety of reduced-dose prasugrel monotherapy after PCI in East Asian patients with acute and chronic coronary syndromes.

A HANC Risk Stratification Score for Antiplatelet Therapy Optimization with Low-Dose Prasugrel in Taiwanese Acute Coronary Syndrome Patients from the Switch Study

BACKGROUND

A significant proportion of acute coronary syndrome (ACS) patients experience high on-treatment platelet reactivity (HPR) on clopidogrel-based dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI).

OBJECTIVES

This study assessed key independent risk factors associated with significant HPR risk on clopidogrel, but not prasugrel, in the Switch Study cohort of 200 Taiwanese ACS patients who switched from clopidogrel to low-dose prasugrel for maintenance DAPT after PCI.

METHODS

Univariate analysis and stepwise multivariate logistic regression analysis were conducted to identify key independent risk factors for HPR on clopidogrel, but not prasugrel.

RESULTS

A HANC [H: low hemoglobin (< 13 g/dL for men and < 12 g/dL for women); A: age ≥ 65 years; N: non-ST elevation myocardial infarction; C: chronic kidney disease as defined by estimated glomerular filtration rate < 60 mL/min] risk stratification score was developed, and demonstrated optimal sensitivity and specificity at a cutoff score of ≥ 2. The HANC score compared favorably against the recently validated ABCD score in the full Switch Study cohort (n = 200), and the ABCD-GENE score in a genotyped cohort (n = 102).

CONCLUSIONS

The HANC score may serve to alert clinicians to patients at potentially higher HPR risk on clopidogrel, but not prasugrel. Further research to validate this score and assess its correlation with clinical outcomes is warranted.

Optimal Antithrombotic Therapy in Patients Undergoing Percutaneous Coronary Intervention: A Focused Review on High Bleeding Risk

Dual antiplatelet therapy (DAPT) is a therapeutic cornerstone to prevent stent thrombosis following percutaneous coronary intervention (PCI) for coronary artery disease (CAD). However, the longer the DAPT duration, the higher the incidence of bleeding and mortality. Since the advent of second-generation drug-eluting stents (DES), the continuous evolution of DES has reduced the thrombotic risk and allowed for a shorter DAPT duration. On the other hand, concerns on the elevated risk of bleeding during antithrombotic therapy have been further raised due to the growing number of elderly CAD patients with multiple comorbidities. The consequent debate topic over post-PCI antithrombotic therapy has shifted from simply reducing thrombotic risk to safely minimizing bleeding risk. Due to the significant impact of bleeding on clinical outcomes, including prognosis, current guidelines on antithrombotic therapy for CAD prioritize stratification of patients at a high bleeding risk (HBR) as the top consideration in determining post-PCI antithrombotic therapy. Achieving optimal antithrombotic therapy for each patient undergoing PCI requires a better understanding of the clinical variables constituting the balance of bleeding and thrombotic risk. This review highlights relevant evidence required to optimize antithrombotic therapy for HBR patients undergoing PCI.

Early P2Y12 Inhibitor Single Antiplatelet Therapy for High-Bleeding Risk Patients After Stenting - PENDULUM Mono 24-Month Analysis

BACKGROUND

In PENDULUM mono, Japanese patients with high bleeding risk (HBR) received short-term dual antiplatelet therapy (DAPT) followed by single antiplatelet therapy (SAPT) with prasugrel after percutaneous coronary intervention (PCI). One-year data from PENDULUM mono showed better outcomes with prasugrel monotherapy after short-term DAPT compared with matched patients in the PENDULUM registry with longer DAPT durations according to guidelines at that time. This study presents 2-year results.Methods and Results: We compared 24-month data from PENDULUM mono (n=1,107; de-escalation strategy group) and the PENDULUM registry (n=2,273; conventional strategy group); both were multicenter, non-interventional, prospective registry studies, using the inverse probability of treatment weighting (IPTW) method. In the PENDULUM mono group, the cumulative incidence of clinically relevant bleeding (CRB) at 24 months post-PCI (primary endpoint) was 6.8%, and that of major adverse cardiac and cerebrovascular events (MACCE) was 8.9%. After IPTW adjustment, the cumulative incidence of CRB was 5.8% and 7.2% in PENDULUM mono and the PENDULUM registry, respectively (hazard ratio [HR] 0.77; 95% confidence interval [CI] 0.57-1.04; P=0.086), and that of MACCE was 8.0% and 9.5%, respectively (HR 0.77; 95% CI 0.59-1.01; P=0.061).

CONCLUSIONS

Japanese PCI patients with HBR prescribed prasugrel SAPT after short-term DAPT had a lower ischemic event risk than those prescribed long-term DAPT, and this was particularly relevant for ischemic events after 1 year.

Changes in Antithrombotic Therapy Over Time and Durability of a Prasugrel WOEST-Like Regimen for Percutaneous Coronary Intervention Patients With Atrial Fibrillation - Post Hoc Analysis of the PENDULUM Mono and PENDULUM Registries

Background: Previously published randomized atrial fibrillation (AF) percutaneous coronary intervention (PCI) trials have demonstrated the safety and efficacy of a WOEST-like regimen (oral anticoagulant [OAC] plus P2Y12 inhibitor) in patients with AF PCI within 1 year. However, the efficacy of this regimen in real-world practice has not been fully confirmed, especially the efficacy of the WOEST-like regimen using the approved dose of prasugrel in Japan. Methods and Results: This post hoc analysis included 186 and 220 patients from the PENDULUM mono and PENDULUM registries, respectively. Endpoints were the cumulative incidences of clinically relevant bleeding (CRB) and major adverse cardiac and cerebrovascular events (MACCE) at 12 months after PCI. Differences in the enrollment period led to an increase in OAC prescriptions (from 64.7% to 81.2%) and a reduction in the median duration of triple antithrombotic therapy (from 203.0 to 32.0 days) in the PENDULUM vs. PENDULUM mono registries, respectively. After adjustment by the inverse probability of treatment method, in patients with OAC, PENDULUM mono AF significantly reduced CRB without increasing MACCE compared with PENDULUM AF. Conclusions: A WOEST-like regimen with prasugrel may reduce CRB, without increasing MACCE, in Japanese patients with AF and high bleeding risk undergoing PCI.

Platelet reactivity testing in peripheral artery disease

DISCLAIMER

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

Oral antiplatelet therapy is routinely used to prevent adverse cardiovascular events in patients with peripheral artery disease (PAD). Several laboratory tests are available to quantify the degree of platelet inhibition following antiplatelet therapy. This article aims to provide a review of the literature surrounding platelet functional testing in patients with PAD receiving oral P2Y12 inhibitors and to offer guidance to clinicians for the use and interpretation of these tests.

SUMMARY

A literature search of PubMed and the Web of Science Core Collection database was conducted. All studies that performed platelet function testing and reported clinical outcomes in patients with PAD were included. Evaluation of the data suggests that, among the available testing strategies, the VerifyNow platelet reactivity unit (PRU) test is the most widely used. Despite numerous investigations attempting to define a laboratory threshold indicating suboptimal response to antiplatelet therapy, controversy exists about which PRU value best correlates with cardiovascular outcomes (ie, mortality, stent thrombosis, etc). In the PAD literature, the most commonly used PRU thresholds are 208 or higher and 235 or higher. Nonetheless, adjusting antiplatelet regimens based on suboptimal P2Y12 reactivity values has yet to be proven useful in reducing the incidence of adverse cardiovascular outcomes. This review examines platelet function testing in patients with PAD and discusses the interpretation and application of these tests when monitoring the safety and efficacy of P2Y12 inhibitors.

CONCLUSION

Although platelet functional tests may be simple to use, clinical trials thus far have failed to show benefit from therapy adjustments based on test results. Clinicians should be cautioned against relying on this test result alone and should instead consider a combination of laboratory, clinical, and patient-specific factors when adjusting P2Y12 inhibitor therapy in clinical practice.

Dual Loading Antiplatelet Therapy in Patients With Acute Coronary Syndrome and High Bleeding Risk Undergoing Percutaneous Coronary Intervention: Findings From the Improving Care for Cardiovascular Disease in China Project

Objective

Loading dose of dual antiplatelet therapy (LD) is supported by the guidelines for patients with acute coronary syndrome (ACS). However, limited data is provided in the series of high bleeding risk (HBR) patients with ACS and percutaneous coronary intervention (PCI).

Methods

Using data from the Improving Care for Cardiovascular Disease in China—Acute Coronary Syndrome registry, conducted between 2014 and 2019, we stratified all ACS patients with HBR and PCI according to LD used within 24 h of first medical contact or not. Inverse probability of treatment weighting (IPTW) and Cox proportional hazards model with hospital as random effect were used to analyze differences in in-hospital clinical outcomes: the primary efficacy endpoint was mortality, and the primary safety endpoint was bleeding.

Results

Of 21,654 evaluable patients 14,322 (66.2%) were treated with LD, and were on average older, less likely to have comorbidities and higher hemoglobin, more often treated GPI and anticoagulant during hospitalization than those without LD. After IPTW adjustment for baseline differences, LD was associated with significantly increased risk of in-hospital mortality [1.89 vs. 1.02%; hazard ratio (HR): 1.71 (95% confidence interval 1.12, 2.42); p &lt; 0.001] and in-hospital bleeding [3.89 vs. 3.3%; HR: 1.25 (1.03, 1.53); p = 0.03].

Conclusions

In ACS patients with HBR, LD was associated with an increased risk of in-hospital mortality and bleeding complications after PCI. Dedicated randomized trials with contemporary ACS management are needed to confirm these findings.

Relationship between platelet aggregation and stroke risk after percutaneous coronary intervention: a PENDULUM analysis

In patients undergoing percutaneous coronary intervention (PCI) with a stent, high on-treatment platelet reactivity may be associated with an increased risk of stroke. This post hoc analysis of the PENDULUM registry compared the risk of post-PCI stroke according to on-treatment P2Y₁₂ reaction unit (PRU) values. Patients aged ≥ 20 years who underwent PCI were stratified by baseline PRU (at 12 and 48 h post-PCI) as either high (HPR, > 208), optimal (OPR, > 85 to ≤ 208), or low on-treatment platelet reactivity (LPR, ≤ 85). The incidences of non-fatal ischemic and non-ischemic stroke through to 12 months post-PCI were recorded. Almost all enrolled patients (6102/6267 [97.4%]) had a risk factor for ischemic stroke, and most were receiving dual antiplatelet therapy. Of the 5906 patients with PRU data (HPR, n = 2227; OPR, n = 3002; LPR, n = 677), 47 had a non-fatal stroke post-PCI (cumulative incidence: 0.68%, ischemic; 0.18%, non-ischemic stroke). Patients with a non-fatal ischemic stroke event had statistically significantly higher post-PCI PRU values versus those without an event (P = 0.037). The incidence of non-fatal non-ischemic stroke was not related to PRU value. When the patients were stratified by PRU ≤ 153 versus > 153 at 12–48 h post-PCI, a significant difference was observed in the cumulative incidence of non-fatal stroke at 12 months (P = 0.044). We found that patients with ischemic stroke tended to have higher PRU values at 12–48 h after PCI versus those without ischemic stroke.

Clinical trial registration: UMIN000020332.

Ischemic and Bleeding Events After First Major Bleeding Event in Patients Undergoing Coronary Stent Implantation

There is a scarcity of data on ischemic and bleeding events in patients who experienced major bleeding after percutaneous coronary intervention (PCI). Moreover, there also is a shortage of data on comparative outcomes between patients with and without interruption of an antithrombotic drug after major bleeding. We evaluated the incidence and prognostic impacts of ischemic (myocardial infarction or ischemic stroke) and bleeding (Bleeding Academic Research Consortium type 3 or 5) events after major bleeding in 12,691 consecutive patients who underwent first PCI in the Coronary Revascularization Demonstrating Outcome Study in Kyoto PCI registry cohort-3. In the entire cohort, incidence of the first ischemic event and bleeding event was 2.3 per 100 person-years and 3.8 per 100 person-years, respectively. Major bleeding (Bleeding Academic Research Consortium type 3) occurred in 2,142 patients during a median follow-up of 5.7 years. In patients with major bleeding, cumulative 30-day, 1-year, and 5-year incidence of an ischemic event was 2.6%, 4.8%, and 13.2% (3.2 per 100 person-years), respectively, whereas that of a bleeding event was 6.3%, 16.1%, and 29.2% (8.5 per 100 person-years), respectively. Ischemic and bleeding events were independently associated with mortality (hazard ratio 2.36, 95% confidence interval 1.87 to 2.96, p <0.001, and hazard ratio 2.85, 95% confidence interval 2.42 to 3.37, p <0.001). The cumulative 180-day incidence of ischemic and bleeding events was not significantly different between patients with and without interruption of an antithrombotic drug in patients with major bleeding. In conclusion, the incidence of an ischemic event after the first major bleeding was approximately 1/3 of that of recurrent major bleeding, and the rates of ischemic and bleeding events after the first major bleeding were higher than the rates of first events in the general PCI population. Both ischemic events and bleeding events were strongly associated with subsequent mortality. The incidence of ischemic and recurrent bleeding events was not different between patients with and without interruption of an antithrombotic drug.

Pragmatic Clinical Studies: An Emerging Clinical Research Discipline for Improving Evidence-Based Practice of Cardiovascular Diseases in Asia

Pragmatic clinical studies, as an emerging clinical research discipline, include a wide range of studies that are largely embedded with routine clinical practice aiming to evaluate comparative effectiveness and safety of different clinical intervention strategies. In this review, we described the evolution of the conceptual framework of pragmatic clinical studies, shared perspectives on the importance of pragmatic clinical studies for cardiovascular diseases as a complement to conventional randomized controlled trials, as well as highlighted the specific importance of pragmatic clinical research in improving evidence-based practice for cardiovascular disease managements in Asia.

Pragmatic clinical studies, an emerging clinical research discipline, include a wide range of studies that are largely embedded with routine clinical practice and aim to evaluate the comparative effectiveness and safety of different clinical intervention strategies. Increased availability and quality of electronic medical/health records drives the development of pragmatic clinical studies. In this review, we describe evolution of the conceptual framework of pragmatic clinical studies and share perspectives on the importance of pragmatic clinical studies in evidence-based practice for cardiovascular diseases, as a complement to conventional randomized controlled trials. We also highlight specific needs of pragmatic clinical studies in improving evidence-based practice for cardiovascular disease in Asian countries. The main challenges of pragmatic clinical studies are discussed briefly in this review.

Derivation of a Novel Scoring System Predicting High Platelet Reactivity on Prasugrel in Patients with Coronary Artery Disease

AIMS

High platelet reactivity (HPR) has been associated with an increased risk of thrombotic events in patients undergoing percutaneous coronary intervention. HPR has been well examined in patients treated with clopidogrel; however, HPR on prasugrel is poorly investigated.

METHODS

Four prospective studies were pooled, in which platelet reactivity on prasugrel was measured using VerifyNow assay; genotyping of CYP2C19 was also performed. Factors associated with HPR on prasugrel were identified using multivariable analysis to develop a risk prediction model.

RESULTS

In total, 180 patients were examined in this study, of whom 51 (28%) had HPR on prasugrel. The multivariable analysis indicated that hypertension, diabetes, hemodialysis, and the number of CYP2C19 loss-of-function (LOF) alleles are significant factors for HPR on prasugrel. These four factors were then incorporated to develop the HHD-GENE score. The receiver operating characteristic curve analysis showed that the HHD-GENE score predicted HPR on prasugrel (area under the curve (AUC) 0.74, best cutoff value 5, p＜0.001). With the best cutoff value, patients with the HHD-GENE score ≥ 5 had a significantly increased risk of HPR on prasugrel than their counterpart (50% vs. 18%, p＜0.001).

CONCLUSIONS

The HHD-GENE score consisting of hypertension, diabetes, hemodialysis, and CYP2C19 LOF alleles may be useful in identifying patients on prasugrel who are at high risk for HPR. External validation is needed to define the clinical utility of this novel scoring system.

Ischemic and Bleeding Events in PENDULUM Patients With High Bleeding Risk and High Platelet Reactivity

BACKGROUND

The balance between thrombotic and bleeding risk is of great concern in high bleeding risk (HBR) patients. This study evaluated the relationship between perioperative antiplatelet reactivity and thrombotic and bleeding events in patients at HBR undergoing percutaneous coronary intervention (PCI).Methods and Results:In this post hoc analysis of the PENDULUM (Platelet rEactivity in patieNts with DrUg eLUting stent and balancing risk of bleeding and ischeMic event) registry, patients undergoing PCI were categorized as HBR or non-HBR, and stratified as having high platelet reactivity (HPR; P2Y₁₂reaction unit [PRU] >208) or non-HPR (PRU ≤208). Cumulative incidences of cardiovascular and cerebrovascular events (Journal of the American College of Cardiologyexpert definitions) and bleeding events (Bleeding Academic Research Consortium criteria) were assessed 12 months after index PCI. The incidence of ischemic and bleeding events was ~3-fold higher in HBR vs. non-HBR patients. Thrombotic/ischemic events were significantly more common in the HPR subgroup in HBR patients (hazard ratio [HR]: 1.59; 95% confidence interval [CI]: 1.11-2.28; P=0.012), but there was no difference in non-HBR patients. After adjustment for covariates, HPR in HBR patients remained an independent factor for thrombotic and ischemic events (HR: 1.69; 95% CI: 1.13-2.54; P=0.011), but not for bleeding events (HR: 1.56; 95% CI: 0.78-3.11; P=0.210).

CONCLUSIONS

Maintaining adequate PRU levels during PCI is an important factor in improving clinical outcomes, especially for HBR patients.

Differential Impact of Clinical and Genetic Factors on High Platelet Reactivity in Patients with Coronary Artery Disease Treated with Clopidogrel and Prasugrel

AIM

High platelet reactivity (HPR) is associated with increased risks of thrombotic events in patients with coronary artery disease. The recently developed ABCD-GENE score identified five clinical and genetic factors (age, body mass index, chronic kidney disease, diabetes, and the CYP2C19 loss-of-function allele) for HPR, although the significance of various stages of each factor is unclear.

METHODS

Four prospective studies were pooled, in which platelet reactivity was measured using the VerifyNow assay with clopidogrel and prasugrel; genotyping of CYP2C19 was also performed. Each component of the ABCD-GENE score was divided into three subcategories. VerifyNow P2Y12 reactivity units ＞208 were defined as HPR.

RESULTS

A total of 184 patients were included, of which 111 (60%) and 51 (28%) had HPR with clopidogrel and prasugrel. Chronic kidney disease had an impact on HPR on both clopidogrel and prasugrel, whereas the impact of diabetes was more evident in patients treated with prasugrel. Although the number of CYP2C19 loss-of-function alleles was clearly associated with a likelihood of HPR with clopidogrel, P2Y12 reactivity units with prasugrel treatment were also significantly and progressively higher in patients with more CYP2C19 loss-of-function alleles.

CONCLUSIONS

Clinical and genetic factors had a differential effect on a P2Y12 inhibitor reactivity with clopidogrel and prasugrel in patients with coronary artery disease. The severity of the factors also had a different impact on HPR.

Single Antiplatelet Therapy With Prasugrel vs. Dual Antiplatelet Therapy in Japanese Percutaneous Coronary Intervention Patients With High Bleeding Risk

BACKGROUND

Outcomes with prasugrel single antiplatelet therapy (SAPT) vs. dual antiplatelet therapy (DAPT) in Japanese percutaneous coronary intervention (PCI) patients with high bleeding risk (HBR) are currently unknown.Methods and Results:Data from 1,173 SAPT and 2,535 DAPT patients from the PENDULUM mono and PENDULUM registry studies (respective median DAPT durations: 108 vs. 312 days) were compared. The adjusted cumulative incidence of Bleeding Academic Research Consortium (BARC) 2, 3, or 5 bleeding from 1 to 12 months after PCI (primary endpoint) was 2.8% (95% confidence interval [CI], 1.9-4.2) and 4.1% (95% CI, 3.3-5.1), respectively (hazard ratio [HR], 0.69; 95% CI, 0.45-1.06; P=0.090). The adjusted cumulative incidences of BARC 2, 3, or 5 bleeding from 0 to 12 months after PCI (secondary endpoint) were 3.8% (95% CI, 2.7-5.3) and 5.6% (95% CI, 4.7-6.7), respectively (HR, 0.68; 95% CI, 0.47-0.98; P=0.039). There was no significant difference in major adverse cardiac and cerebrovascular events (MACCE) from 1 to 12 months after PCI (HR, 0.93; 95% CI, 0.63-1.37; P=0.696) and at 12 months after PCI (HR, 0.85; 95% CI, 0.61-1.19; P=0.348) between the groups.

CONCLUSIONS

Prasugrel SAPT may reduce BARC 2, 3, or 5 bleeding, without increasing MACCE, in Japanese patients with HBR.

Prasugrel switching from clopidogrel after percutaneous coronary intervention for acute coronary syndrome in Taiwanese patients: an analysis of safety and efficacy

The recommended maintenance dose of prasugrel for East Asian populations (i.e., Japanese and Taiwanese) is 3.75 mg as part of dual antiplatelet therapy (DAPT) for the prevention of recurrent ischemia and stent thrombosis in acute coronary syndrome (ACS). This modified dosage regimen has been established in studies conducted in Japan; however, the efficacy and safety of switching from clopidogrel to prasugrel DAPT among Taiwanese patients remain to be explored. In this phase IV, multicenter, single-arm, open-label study, we evaluated the 4-week pharmacodynamic response, and the 48-week safety outcomes of prasugrel 3.75 mg after a switch from clopidogrel in Taiwanese ACS patients. A total of 203 prasugrel-naïve ACS patients (over 90% male) who had received post-PCI clopidogrel DAPT for at least 2 weeks were enrolled from ten medical centers in Taiwan and subsequently switched to prasugrel 3.75 mg DAPT. Four weeks after the switch, P2Y12 reaction unit (PRU) values were significantly decreased in the total cohort (mean − 18.2 ± 48.1; 95% confidence interval − 24.9 to − 11.5, p < 0.001), and there was an overall consistent antiplatelet response in the treated subjects. The proportion of patients with high on-treatment platelet reactivity (HPR; PRU > 208) dropped from 23.5 to 10% (p < 0.001). Female sex was associated with a greater PRU reduction with prasugrel, whereas HPR at baseline, age ≥ 65 years, and body mass index ≥ 25 best predicted HPR at Week 4. Throughout the 48-week treatment with prasugrel, the incidences of MACE (1.0%) and TIMI major bleeding (2.0%) were rather low, accompanying an acceptable safety profile of TIMI minor (6.4%) and non-major, non-minor clinically relevant bleeding (3.0%). Overall, switching to the maintenance dose of prasugrel (3.75 mg) was observed to be effective and well tolerated among post-PCI ACS patients in Taiwan. Clinical Trial Registration Number: NCT03672097.

High bleeding risk and clinical outcomes in East Asian patients undergoing percutaneous coronary intervention: the PENDULUM registry

AIMS

We aimed to evaluate the validity of the Academic Research Consortium for High Bleeding Risk (ARC-HBR) criteria for East Asian patients undergoing contemporary percutaneous coronary intervention (PCI) from the PENDULUM registry.

METHODS AND RESULTS

This post hoc analysis included 6,267 Japanese patients undergoing PCI between December 2015 and June 2017 enrolled in PENDULUM. The primary endpoint was the incidence of major bleeding at 12 months post index PCI. In total, 3,185 (50.8%) and 3,082 (49.2%) patients were stratified to the ARC-HBR and non-ARC-HBR groups, respectively, and almost all patients had overlapping criteria. Incidence of major bleeding was 4.2% versus 1.4% in the ARC-HBR group versus the non-ARC-HBR group (hazard ratio 3.00 [95% confidence interval: 2.11-4.27]; p<0.001). As the number of overlapping ARC-HBR criteria increased, the incidence of major bleeding also increased. In contrast, the incidence of major bleeding was 4.2% for one major criterion, 2.1% for two minor criteria. Multivariate analysis suggested that severe CKD, anticoagulant use, acute coronary syndrome, low body weight and heart failure were independent predictors of major bleeding.

CONCLUSIONS

Half of the Japanese patients who underwent PCI in the PENDULUM registry met the ARC-HBR criteria, and many patients had overlapping criteria. ARC-HBR criteria are applicable to Japanese patients undergoing contemporary PCI.

Drug-eluting stent thrombosis: current and future perspectives

Over the past 40 years, the safety and efficacy of percutaneous coronary intervention has dramatically improved by overcoming several challenges. The introduction of drug-eluting stent (DES) in particular was a major breakthrough in interventional cardiology. Compared to bare-metal stents, first-generation DES (G1-DES) has dramatically reduced the rates of in-stent restenosis and subsequent target lesion revascularization. However, major safety concerns surrounding stent thrombosis (ST) emerged with G1-DES in clinical practice as a result of the high incidences of death, myocardial infarction, and repeat revascularization associated with ST. To overcome these limitations, second-generation DES (G2-DES) has been developed with an improved stent platform with thinner strut and biocompatible durable or biodegradable polymers. Indeed, G2-DES, when compared with G1-DES, has improved clinical outcomes by reducing the risk of late thrombotic events while maintaining anti-restenotic efficacy, whereas ST still occurs, even with the use of G2-DES. This review gives an overview of pathophysiology, risk factors, and outcomes of ST after DES implantation. Additionally, we discuss the management and prevention of ST.

Comparison of the 9-Month Intrastent Condition and 30-Month Clinical Outcomes After Resolute Zotarolimus-Eluting Stent Implantation Between Standard-Duration and 1-Month Dual Antiplatelet Therapy Followed by Prasugrel Monotherapy

Background: In this study we investigated the efficacy and safety of very short duration (1-month) dual antiplatelet therapy (DAPT) followed by prasugrel monotherapy. In particular, we compared intrastent conditions using optical coherence tomography (OCT) after second-generation drug-eluting stent implantation between standard-duration and 1-month DAPT followed by prasugrel monotherapy.

Methods and Results: Between May 2015 and February 2018, 120 consecutive patients who underwent elective Resolute zotarolimus-eluting stent implantation were enrolled and divided into those receiving standard-duration or 1-month (1M) DAPT followed by prasugrel monotherapy; 47 patients (n=55 stents) and 46 patients (n=54 stents) in the standard and 1M groups, respectively, completed the protocol. The primary endpoint was the prevalence of abnormal intrastent tissue at the 9-month examination, as observed by OCT. The secondary endpoint was the presence of composite adverse events, including all-cause death, myocardial infarction, stent thrombosis, target lesion and vessel revascularization, and major and minor bleeding. The prevalence of abnormal intrastent tissue was similar between the standard and 1M groups (1.6% vs. 1.5%, respectively; non-inferiority P<0.01). There was a tendency for fewer composite events in the 1M than standard group at the 30-month follow-up examination (28.3% vs. 44.7%, respectively; P=0.41).

Conclusions: In conclusion, 1M DAPT followed by prasugrel monotherapy after second-generation drug-eluting stent implantation was not inferior to standard-duration DAPT in terms of intrastent thrombus formation and composite adverse events.

Monotherapy With Prasugrel After Dual-Antiplatelet Therapy for Japanese Percutaneous Coronary Intervention Patients With High Bleeding Risk - A Prospective Cohort Study (PENDULUM mono Study)

BACKGROUND

The risks of bleeding and cardiovascular events in high bleeding risk (HBR) Japanese patients undergoing percutaneous coronary intervention (PCI) while receiving single-antiplatelet therapy (SAPT) remains unknown. We aimed to evaluate the frequency of bleeding and cardiovascular events associated with prasugrel monotherapy after short-term dual-antiplatelet therapy (DAPT) in Japanese HBR patients after PCI.Methods and Results:The PENDULUM mono study was a multicenter, non-interventional, prospective registry (n=1,173). The primary endpoint was the cumulative incidence of clinically relevant bleeding (CRB; Bleeding Academic Research Consortium types 2, 3, and 5) from 1 to 12 months after PCI. Secondary endpoints included major adverse cardiac and cerebrovascular events (MACCE). The proportion of patients who received prasugrel monotherapy at 12 months after PCI was 79.7%, and no cases of stent thrombosis were observed among these patients. The cumulative incidence of CRB was 3.2% from 1 to 12 months after PCI; that of MACCE was 3.8%. Severe anemia, chronic kidney disease, oral anticoagulant use at discharge, and heart failure were significantly associated with CRB.

CONCLUSIONS

Among HBR patients undergoing PCI who were not suitable for concomitant aspirin and were scheduled for prasugrel monotherapy, most patients were on prasugrel monotherapy after DAPT. Cumulative incidences of CRB and MACCE after periprocedural period were 3.2% and 3.8%, respectively, and no cases of stent thrombosis were reported. SAPT might be a suitable alternative to DAPT.

Prasugrel for Japanese Patients With Ischemic Heart Disease in Long-Term Clinical Practice (PRASFIT-Practice II) - Final 2-Year Follow-up Results of a Postmarketing Observational Study

BACKGROUND

PRASFIT-Practice II is a postmarketing observational study conducted in 4,155 Japanese patients with ischemic heart disease (IHD) who received long-term prasugrel. The data were used to assess the utility of Academic Research Consortium for High Bleeding Risk (ARC-HBR) criteria.Methods and Results:Patients in PRASFIT-practice II were clinically followed for 2 years. The primary endpoint was the cumulative incidence of major adverse cardiovascular events (MACE) and Thrombolysis in Myocardial Infarction (TIMI) major/minor bleeding. Patients were divided into 2 groups based on ARC-HBR criteria (HBR (40.1% of patients) and non-HBR (59.9%)) and the effect of HBR on the primary endpoint was assessed. The median duration of dual antiplatelet therapy with prasugrel was 391.0 days. At 2 years, the cumulative incidence of MACE was 3.3%, and of TIMI major/minor bleeding was 2.7%. At 1 year, MACE and TIMI major/minor bleeding in the HBR group (4.0% and 3.4%, respectively) were higher than that in the non-HBR group (1.3% for both). Landmark analysis at 3 months and 1 year showed that the higher risk of MACE or TIMI major/minor bleeding in the HBR group persisted through 2 years.

CONCLUSIONS

The results of this study confirmed the safety and effectiveness of long-term treatment with prasugrel, and demonstrated that the ARC-HBR criteria for bleeding risk are applicable in Japanese IHD patients treated with prasugrel.

Relationship Between Platelet Reactivity and Ischemic and Bleeding Events After Percutaneous Coronary Intervention in East Asian Patients: 1-Year Results of the PENDULUM Registry

Background The balance between ischemic and bleeding events and their association with platelet reactivity in patients receiving antiplatelet therapy after percutaneous coronary intervention (PCI), which differs among regions, is not fully evaluated for East Asians. We examined ischemic/bleeding events and platelet reactivity in Japanese patients undergoing PCI and determined associations between high/low platelet reactivity and clinical outcomes. Methods and Results PENDULUM (Platelet Reactivity in Patients with Drug Eluting Stent and Balancing Risk of Bleeding and Ischemic Event) is a prospective, multicenter registry of Japanese patients with PCI. Primary end points were incidence of first major adverse cardiac and cerebrovascular events (MACCE) and first major bleeding events at 12 months post-PCI. Platelet reactivity (P2Y₁₂ reaction unit [PRU] value) was measured at 12 to 48 hours post-PCI; patients were grouped as having high PRU (>208), optimal PRU (>85 to ≤208), and low PRU (≤85). MACCE and major bleeding occurred in 4.4% and 2.8% of 6267 patients, respectively. The mean±SD PRU value was 182.1±77.1. MACCE was significantly higher in the high PRU (5.7%; n=2227) versus the optimal PRU group (3.6%; n=3002). The hazard ratio (HR) for high PRU versus optimal PRU level was significantly higher for MACCE (adjusted HR, 1.53; 95% CI, 1.14-2.06 [P=0.004]); stent thrombosis followed the same trend. Incidence of major bleeding did not differ significantly between groups. A high PRU level was significantly associated with MACCE in both patients with and patients without acute coronary syndrome. Conclusions These real-world data suggest an association between high platelet reactivity and cardiovascular events in Japanese patients undergoing PCI. The trend was the same in both patients with and patients without acute coronary syndrome. REGISTRATION URL: https://www.umin.ac.jp/ctr. Unique identifier: UMIN 000020332.