Quantifying Ischemic Risk After Percutaneous Coronary Intervention Attributable to High Platelet Reactivity on Clopidogrel (From the Assessment of Dual Antiplatelet Therapy with Drug-Eluting Stents Study)

Comparison of ticagrelor and clopidogrel in anemic patients with acute coronary syndrome: efficacy and safety outcomes over one year

OBJECTIVE

This retrospective study aimed to investigate the potential impact of ticagrelor and clopidogrel treatment on cardiovascular outcomes in patients with anemia and acute coronary syndrome (ACS) and to provide insights into the optimal therapeutic approach for this vulnerable patient population.

METHODS

A retrospective research design was employed, involving patients diagnosed with ST-segment elevation myocardial infarction (STEMI) or non-ST-segment elevation myocardial infarction (NSTEMI) between 2014 and 2021. Inclusion criteria required a hemoglobin level below 12 mg/dL and a minimum 12-month P2Y12 inhibitor treatment. Comprehensive clinical, biochemical, and echocardiographic data were collected from the hospital's electronic repository. The primary efficacy endpoint was major adverse cardiovascular events (MACE), encompassing total mortality, cardiovascular mortality, reinfarction, ischemic stroke, and hemorrhagic stroke. Major hemorrhage was the primary safety endpoint. Secondary outcomes included total mortality, cardiovascular mortality, reinfarction, ischemic stroke, and hemorrhagic stroke, individually.

RESULTS

Patients treated with ticagrelor (n = 118) and clopidogrel (n = 538) were compared. No significant difference was observed in major adverse cardiovascular events (MACE) and major bleeding between ticagrelor and clopidogrel treatment groups (MACE: clopidogrel 10.0% vs. ticagrelor 11.0%, p = 0.75; major bleeding: clopidogrel 2.8%, ticagrelor 2.5%, p = 0.88). Patients with hemoglobin levels ≤ 8 mg/dL demonstrated significantly higher MACE and major bleeding rates in the ticagrelor group (p = 0.008 and p = 0.002, respectively). Among patients aged ≥ 75 years, ticagrelor treatment was associated with a higher risk of major bleeding (p = 0.04).

CONCLUSIONS

Ticagrelor and clopidogrel exhibited comparable efficacy and safety outcomes in anemic ACS patients over a one-year period. Although ticagrelor demonstrated superiority in reducing ischemic events, it is crucial to recognize the limitations of retrospective studies in informing clinical practice. This study offers valuable insights into tailoring antiplatelet therapy for anemic ACS patients and provides guidance for personalized treatment strategies, acknowledging the hypothesis-generating nature of retrospective analyses.

Comparison of Ticagrelor and Clopidogrel in Patients With Acute Coronary Syndrome at High Bleeding or Ischemic Risk

Current guidelines recommend individualizing the choice and duration of P2Y12 inhibitor therapy based on the trade-off between bleeding and ischemic risk. However, whether a potent P2Y12 inhibitor (ticagrelor) or a less potent one (clopidogrel) is more appropriate in patients with acute coronary syndrome (ACS) in the setting of high bleeding or ischemic risk is not clear. The study aimed to compare the clinical outcomes of clopidogrel and ticagrelor in patients with ACS at high bleeding or ischemic risk. A total of 5,713 patients with ACS were included in this retrospective study. The Cox proportional hazard regression model was adjusted by applying the inverse probability weighted approach to reduce treatment selection bias. The primary clinical outcome was all-cause death. Secondary outcomes included in-hospital death, ACS, target vessel revascularization, stent thrombosis, stroke, or clinically significant or major bleeding. The median follow-up duration was 53.6 months. After multivariable Cox model using an inverse probability weighted approach, all-cause death in the overall population and subgroups of patients at high bleeding risk, and/or at high ischemic risk were not significantly different between clopidogrel and ticagrelor. Rates for secondary outcomes were also similar between the groups. In conclusion, ticagrelor and clopidogrel are associated with comparable clinical outcomes in patients with ACS irrespective of bleeding and ischemic risk.

Clopidogrel-Related High Residual Platelet Reactivity Associated with Estimated Glomerular Filtration Rate in Patients with Acute Ischemic Stroke

INTRODUCTION

There are few studies on the relationship between the occurrence of clopidogrel-related high residual platelet reactivity (HRPR) and estimated glomerular filtration rate (eGFR) at admission in patients with ischemic stroke. The aim of this study was to investigate the possible relationship between the two.

METHODS

Patients who were hospitalized and diagnosed with acute ischemic stroke were recruited from July 1, 2017, to June 30, 2018, at Shanghai TCM-Integrated Hospital. Renal function was measured within 24 h of enrollment and eGFR was calculated. Patients were tested for platelet reactivity using the VerifyNow system after 7 days of antiplatelet therapy with clopidogrel 75 mg/d alone, and patients with P2Y12 reaction unit values ≥230 were diagnosed with HRPR. The association between HRPR and eGFR was analyzed.

RESULTS

A total of 274 patients were enrolled in the study, of whom 91 (33.21%) had HRPR. Multivariate logistic regression analysis suggested that an increased risk of HRPR was independently associated with female sex and reduced eGFR (female sex: OR = 2.24, 95% CI: 1.26-3.99, p = 0.006; mild chronic kidney disease [CKD]: OR = 2.95, 95% CI: 1.47-5.93, p = 0.002; moderate CKD: OR = 3.07, 95% CI: 1.08-8.75, p = 0.04).

CONCLUSION

Decreased eGFR is an independent risk factor for the occurrence of HRPR in patients with ischemic stroke.

Resistance on the Latest Oral and Intravenous P2Y12 ADP Receptor Blockers in Patients with Acute Coronary Syndromes: Fact or Myth?

Novel P2Y12 ADP receptor blockers (ADPRB) should be preferred in dual-antiplatelet therapy in patients with acute coronary syndrome. Nevertheless, there are still patients who do not respond optimally to novel ADP receptor blocker therapy, and this nonoptimal response (so-called "high on-treatment platelet reactivity" or "resistance") could be connected with increased risk of adverse ischemic events, such as myocardial re-infarction, target lesion failure and stent thrombosis. In addition, several risk factors have been proposed as factors associated with the phenomenon of inadequate response on novel ADPRB. These include obesity, multivessel coronary artery disease, high pre-treatment platelet reactivity and impaired metabolic status for prasugrel, as well as elderly, concomitant therapy with beta-blockers, morphine and platelet count for ticagrelor. There is no literature report describing nonoptimal therapeutic response on cangrelor, and cangrelor therapy seems to be a possible approach for overcoming HTPR on prasugrel and ticagrelor. However, the optimal therapeutic management of "resistance" on novel ADPRB is not clear and this issue requires further research. This narrative review article discusses the phenomenon of high on-treatment platelet reactivity on novel ADPRB, its importance in clinical practice and approaches for its therapeutic overcoming.

Circadian variations of platelet reactivity on clopidogrel in patients treated with elective percutaneous coronary intervention

Evidence assessing potential diurnal variations of platelet reactivity in patients on clopidogrel treated with elective percutaneous coronary intervention (PCI) for chronic coronary syndrome (CCS) are currently lacking. We prospectively enrolled 15 patients affected by stable coronary artery disease (CAD) previously treated with elective PCI and on clopidogrel for at least 8 days (administered at 8 a.m.). A significant heterogeneity in diurnal levels of ADP-dependent platelet aggregation was found (p = 0.0004), with a peak of platelet reactivity occurring at the 6 a.m. assessment, which resulted significantly increased compared to the afternoon (6 p.m.) evaluation (255 ± 66 vs 184 ± 67, p = 0.002). In addition, at the early-morning evaluation a considerably high proportion of patients with high platelet reactivity (53.3%) were observed. In conclusion, clopidogrel-induced platelet inhibition in patients with CCS after elective PCI follows a circadian rhythm, thus suggesting that a consistent and durable antiplatelet inhibition is often failed with standard clopidogrel administration at morning.

Platelet reactivity and clinical outcomes following percutaneous coronary intervention in complex higher-risk patients

AIMS

To investigate the levels of platelet reactivity and the impact of high platelet reactivity (HPR) on long-term clinical outcomes of complex higher-risk and indicated patients (CHIP) with stable coronary artery disease (CAD) treated with elective percutaneous coronary intervention (PCI).

METHODS

We enrolled 500 patients undergoing elective PCI for stable CAD and treated with aspirin and clopidogrel. Patients were divided into four groups based on the presence of CHIP features and HPR. Primary endpoint was the occurrence of major adverse clinical events (MACE) at 5 years.

RESULTS

The prevalence of HPR was significantly greater in the CHIP population rather than non-CHIP patients (39.9% vs 29.8%, P = 0.021). Patients with both CHIP features and HPR showed the highest estimates of MACE (22.1%, log-rank P = 0.047). At Cox proportional hazard analysis, the combination of CHIP features and HPR was an independent predictor of MACE (hazard ratio 2.57, 95% confidence interval 1.30-5.05, P = 0.006).

CONCLUSION

Among patients with stable CAD undergoing elective PCI and treated with aspirin and clopidogrel, the combination of CHIP features and HPR identifies a cohort of patients with the highest risk of MACE at 5 years, who might benefit from more potent antiplatelet strategies.

Thrombin Generation as a Method to Identify the Risk of Bleeding in High Clinical-Risk Patients Using Dual Antiplatelet Therapy

Background: Patients using dual antiplatelet therapy after percutaneous coronary intervention are at risk for bleeding. It is currently unknown whether thrombin generation can be used to identify patients receiving dual antiplatelet therapy with increased bleeding risk. Objectives: To investigate whether thrombin generation measurement in plasma provides additional insight into the assessment of bleeding risk for high clinical-risk patients using dual antiplatelet therapy. Methods: Coagulation factors and thrombin generation in platelet-poor plasma were measured in 93 high clinical-risk frail patients using dual antiplatelet therapy after percutaneous coronary intervention. During 12-month follow-up, clinically relevant bleedings were reported. Thrombin generation at 1 and 6 months after percutaneous coronary intervention was compared between patients with and without bleeding events. Results: One month after percutaneous coronary intervention, the parameters of thrombin generation, endogenous thrombin potential, peak height, and velocity index were significantly lower in patients with bleeding in the following months compared to patients without bleeding. At 6 months follow-up, endogenous thrombin potential, peak height, and velocity index were still (significantly) decreased in the bleeding group as compared to non-bleeders. Thrombin generation in the patients' plasma was strongly dependent on factor II, V, and VIII activity and fibrinogen. Conclusion: High clinical-risk patients using dual antiplatelet therapy with clinically relevant bleeding during follow-up show reduced and delayed thrombin generation in platelet-poor plasma, possibly due to variation in coagulation factors. Thus, impaired thrombin-generating potential may be a "second hit" on top of dual antiplatelet therapy, increasing the bleeding risk in high clinical-risk patients. Thrombin generation has the potential to improve the identification of patients using dual antiplatelet therapy at increased risk of bleeding.

Stent Thrombosis Risk Over Time on the Basis of Clinical Presentation and Platelet Reactivity: Analysis From ADAPT-DES

OBJECTIVES

The aim of this study was to determine the risk period for increased stent thrombosis (ST) after percutaneous coronary intervention (PCI) in patients with acute coronary syndromes (ACS) and whether this increased risk is related to high platelet reactivity (HPR).

BACKGROUND

ST risk after PCI is higher among patients with ACS than those with stable ischemic heart disease. When ST risk is highest in patients with ACS and how that is affected by HPR is unknown.

METHODS

Using the ADAPT-DES (Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents) registry, ST rates during 2-year follow-up post-PCI with drug-eluting stents were compared among patients presenting with ACS (myocardial infarction [MI] or unstable angina) or stable ischemic heart disease (non-ACS). Landmark analyses were done at 30 days and 1 year post-PCI. Platelet reactivity on aspirin and clopidogrel post-PCI was assessed using VerifyNow assays.

RESULTS

Of 8,582 patients, 2,063 presented with MI, 2,370 with unstable angina, and 4,149 with non-ACS. Incidence rates of HPR were 48.0%, 43.3%, and 39.8%, respectively (p < 0.001). Within the first 30 days post-PCI, patients presenting with MI had increased ST risk compared with patients with non-ACS (hazard ratio [HR]: 4.52; 95% confidence interval [CI]: 2.01 to 10.14; p < 0.001). After 30 days, relative ST risks were progressively lower and no longer significant between groups (31 days to 1 year post-PCI: HR: 1.97; 95% CI: 0.80 to 4.85; >1 year post-PCI: HR: 0.89; 95% CI: 0.27 to 2.92). The elevated ST risk in patients with MI within 30 days was largely confined to those with HPR on clopidogrel (HR: 5.77; 95% CI: 2.13 to 15.63; p < 0.001).

CONCLUSIONS

Among patients undergoing PCI, rates of ST during 2-year follow-up were highest in those with MI and lowest in those with non-ACS. Increased ST risk in patients with MI was greatest in the first 30 days post-PCI and was observed predominantly among those with increased HPR on clopidogrel. These findings emphasize the importance of adequate P2Y₁₂ inhibition after MI, especially within the first 30 days after stent implantation.

Dual Antiplatelet Therapy Duration Based on Ischemic and Bleeding Risks After Coronary Stenting

BACKGROUND

Complex percutaneous coronary intervention (PCI) is associated with higher ischemic risk, which can be mitigated by long-term dual antiplatelet therapy (DAPT). However, concomitant high bleeding risk (HBR) may be present, making it unclear whether short- or long-term DAPT should be prioritized.

OBJECTIVES

This study investigated the effects of ischemic (by PCI complexity) and bleeding (by PRECISE-DAPT [PREdicting bleeding Complications in patients undergoing stent Implantation and SubsequEnt Dual AntiPlatelet Therapy] score) risks on clinical outcomes and on the impact of DAPT duration after coronary stenting.

METHODS

Complex PCI was defined as ≥3 stents implanted and/or ≥3 lesions treated, bifurcation stenting and/or stent length >60 mm, and/or chronic total occlusion revascularization. Ischemic and bleeding outcomes in high (≥25) or non-high (<25) PRECISE-DAPT strata were evaluated based on randomly allocated duration of DAPT.

RESULTS

Among 14,963 patients from 8 randomized trials, 3,118 underwent complex PCI and experienced a higher rate of ischemic, but not bleeding, events. Long-term DAPT in non-HBR patients reduced ischemic events in both complex (absolute risk difference: -3.86%; 95% confidence interval: -7.71 to +0.06) and noncomplex PCI strata (absolute risk difference: -1.14%; 95% confidence interval: -2.26 to -0.02), but not among HBR patients, regardless of complex PCI features. The bleeding risk according to the Thrombolysis In Myocardial Infarction scale was increased by long-term DAPT only in HBR patients, regardless of PCI complexity.

CONCLUSIONS

Patients who underwent complex PCI had a higher risk of ischemic events, but benefitted from long-term DAPT only if HBR features were not present. These data suggested that when concordant, bleeding, more than ischemic risk, should inform decision-making on the duration of DAPT.

Association Between Residual Platelet Reactivity on Clopidogrel Treatment and Severity of Coronary Atherosclerosis: Intrinsic Hypercoagulability as a Mediator

INTRODUCTION

High on-treatment residual platelet reactivity (HRPR) was associated with greater atherosclerosis burden. We examined whether intrinsic hypercoagulability (IHC) could be attributed to that association in patients treated by drug-eluting stents.

METHODS

This retrospective observation enrolled a total of 891 coronary artery disease (CAD) subjects. Platelet and coagulant reactivity was measured by thrombelastography. At least 24 h after a 300-mg dose of clopidogrel, adenosine diphosphate (ADP)-induced maximum amplitude of clot strength (MA_adp) > 47 mm represented HRPR. Thrombin-induced platelet-fibrin clot strength (MA_thrombin) and blood fibrinogen surrogated intrinsic coagulability. Using mediation analysis to evaluate the effect of IHC on the relationship between the number of narrowed coronaries and HRPR on clopidogrel.

RESULTS

More HRPR on clopidogrel and higher intrinsic coagulability were observed in more severe coronary atherosclerosis, especially in the three-vessel disease. After adjustment for confounding factors, the number of narrowed coronaries (OR_adj = 1.343, 95% CI 1.063-1.695, p = 0.013), MA_thrombin (OR_adj = 1.106, 95% CI 1.058-1.157, p < 0.001), and fibrinogen (OR_adj = 1.003, 95% CI 1.001-1.005, p = 0.012) were all independent positive predictors for HRPR. MA_thrombin and fibrinogen were meaningful mediators for the significant positive association of the number of narrowed vessels and HRPR on clopidogrel, which were enhanced by around 30% and 43%, respectively, for this effect.

CONCLUSIONS

This is the first study to demonstrate that the positive correlation between the number of stenotic coronaries and HRPR on clopidogrel may be partly attributed to IHC, which may enhance the risk stratification, guide more precise coagulation in multi-vessel disease after drug-eluting stents, and therefore deserve further study.

Predictive Value of Methods Measuring Platelet Activation for Ischemic Events in Patients Receiving Clopidogrel: A Systematic Review and Meta-analysis

This study investigates the efficiency and predictive value of light-transmission aggregometry (LTA), vasodilator-stimulated phosphoprotein (VASP) and VerifyNow for ischemia in patients undergoing percutaneous coronary intervention (PCI). Studies that used LTA, VASP or VerifyNow to predict ischemia were included, and their quality and efficiency were analyzed using Review Manager 5.3. The sensitivity and specificity of subgroup studies based on the outcome, cut-off value, and follow-up days were calculated and the summary ROC (sROC) curves were compared after having been fitted. Thirty-one studies including a total of 17,314 participants were analyzed. LTA, VASP and VerifyNow presented a considerable efficiency in predicting ischemic clinical events. In the subgroup analysis, the sensitivities of LTA, VASP and VerifyNow in predicting cardiac death, all-cause death, myocardial infarction, stent thrombosis, stroke, and revascularization were 0.40/0.63/0.62, 0.47/0.56/0.39, 0.40/0.48/0.60, 0.44/0.58/0.70, 0.29/not applicable/0.60 and 0.44/0.57/0.37, respectively and the specificities of LTA, VASP, and VerifyNow were 0.85/0.48/0.63, 0.73/0.52/0.63, 0.74/0.55/0.64, 0.75/0.47/0.61, 0.72/not applicable/ 0.61, and 0.70/0.47/0.67, respectively. LTA showed a higher sensitivity in predicting the outcomes over six months than those within six months, while VerifyNow prediction sensitivity was found to be higher within six months. Meanwhile, VerifyNow showed no statistically significant higher AUC of sROC in comparison to LTA and VASP in predicting ischemic events in patients undergoing clopidogrel treatment. The cut-off values of LTA, VASP and VerifyNow were suggested to be 56%, 50% and 235 respectively according to our study.

Independent Predictors of Adverse Cardiovascular Events in Patients With Acute Coronary Syndrome After Percutaneous Coronary Intervention During Hospitalization

PURPOSE

to elucidate independent clinical and laboratory predictors of adverse cardiovascular events (ACVE) in patients with acute coronary syndrome (ACS) after percutaneous coronary intervention (PCI) with stenting in early inhospital period.

MATERIALS AND METHODS

We included in this prospective single center study 130 patients with ACS who underwent PCI with stenting. All patients prior to and after PCI received dual antiplatelet therapy with acetylsalicylic acid and clopidogrel. In 12-48 hours after PCI we measured residual platelet reactivity (RPR) using light aggregometry. In 57 patients simultaneously we performed genotyping of CYP2C19*2 polymorphisms. The following ACVE were used as end-points and were registered during inhospital observation (mean duration 9.7±3.2 days): sudden death, stent thrombosis, arterial thrombosis of other localization, recurrent angina, cardiac rhythm disturbances requiring special therapy.

RESULTS

Repetitive ACVE were observed in 32 patients. According to unifactorial regression analysis risk factors of their development were, ADP F-induced RPR (р&lt;0.001), levels of creatinine (р&lt;0.001), hemoglobin (р&lt;0.001), and glucose (р=0.026), age (р=0.01), iron-deficiency anemia (р=0.01), left ventricular ejection fraction (р=0.004), number of stents (р=0.015). According to results of multifactorial regression analysis independent predictors of ACVE were: ADP-induced RPR &gt;76 % (р=0.003), levels of creatinine &gt;189 µmol / L (р=0.003), and hemoglobin &lt;114 g / L (р=0.004). Significant effect of homozygous carriage of CYP2C19*2 (G681A) (А / А) on development of stent thrombosis was also detected (р=0.028).

CONCLUSION

ADP-induced RPR, levels of creatinine and hemoglobin were found to be independent predictors of inhospital ACVE after myocardial revascularization with stenting in patients with ACS.