Antiplatelet Effect of Different Loading Doses of Ticagrelor in Patients With Non–ST-Elevation Acute Coronary Syndrome Undergoing Percutaneous Coronary Intervention: The APELOT Trial

Effect of pretreatment with a P2Y12 inhibitor in patients with non-ST-elevation acute coronary syndrome: a systematic review and network meta-analysis

Background

This study aimed to systematically evaluate the effects of different types and doses of pretreatment with P2Y12 inhibitors in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) undergoing percutaneous coronary intervention (PCI).

Methods

Electronic databases were searched for studies comparing pretreatment with different types and doses of P2Y12 inhibitors or comparison between P2Y12 inhibitor pretreatment and nonpretreatment. Electronic databases included the Cochrane Library, PubMed, EMBASE, and Web of Science. Literature was obtained from the establishment of each database until June 2022. The patients included in the study had pretreatment with P2Y12 inhibitors with long-term oral or loading doses, or conventional aspirin treatment (non-pretreatment). The primary endpoint was major adverse cardiac and cerebrovascular events (MACCEs) during follow-up within 30 days after PCI, which included determining the composite endpoints of cardiac death, myocardial infarction, ischemia-driven revascularization, and stroke. The safety endpoint was a major bleeding event.

Results

A total of 119,014 patients from 21 studies were enrolled, including 13 RCTs and eight observational studies. A total of six types of interventions were included-nonpretreatment (placebo), clopidogrel pretreatment, ticagrelor pretreatment, prasugrel pretreatment, double loading pretreatment (double loading dose of clopidogrel, ticagrelor, prasugrel) and P2Y12 inhibitors pretreatment (the included studies did not distinguish the types of P2Y12 inhibitors, including clopidogrel, ticagrelor, and prasugrel). The network meta-analysis results showed that compared to patients without pretreatment, patients receiving clopidogrel pretreatment (RR = 0.78, 95% CI:0.66, 0.91, P < 0.05) and double-loading pretreatment (RR = 0.62, 95% CI:0.41, 0.95, P < 0.05) had a lower incidence of MACCEs. There was no statistically significant difference in the incidence of major bleeding events among the six pretreatments (P > 0.05).

Conclusions

In patients with NSTE-ACS, pretreatment with P2Y12 inhibitors before percutaneous intervention reduced the incidence of recurrent ischemic events without increasing the risk of major bleeding after PCI compared with nonpretreatment. Clopidogrel or double loading dose P2Y12 inhibitors can be considered for the selection of pretreatment drugs.

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.

Tackling the gap in platelet inhibition with oral antiplatelet agents in high-risk patients undergoing percutaneous coronary intervention

Introduction: Oral P2Y₁₂ inhibitors represent the mainstay therapy for the prevention of thrombotic complications in patients presenting with an acute coronary syndrome and/or undergoing percutaneous coronary intervention (PCI). However, the onset of antiplatelet action of the oral P2Y₁₂ inhibitors is affected by their need to be absorbed in the gastrointestinal (GI) tract before becoming systemically available.Areas covered: Following oral intake of P2Y₁₂ inhibitors, the timeframe required for GI absorption leads to a window of inadequate antiplatelet protection during which patients are at increased thrombotic risk. The onset of action of the oral P2Y₁₂ inhibitors is even further delayed in high-risk patients, underscoring the need to define strategies to bridge the gap in platelet inhibitory effects following their intake.Expert opinion: Multiple mechanisms may impair GI absorption leading to a delay in the onset of action of oral P2Y₁₂ inhibitors. Several strategies have been tested to overcome the gap in platelet inhibition in high-risk patients undergoing PCI. These include administration of crushed or chewed tablets to improve the dissolution rate and use of opioid receptor antagonists or metoclopramide to counteract impairment of gastric motility induced by opioids. However, intravenous antiplatelet therapies represent the most effective strategy to bridge such gap in platelet inhibition.

2020 Asian Pacific Society of Cardiology Consensus Recommendations on the Use of P2Y12 Receptor Antagonists in the Asia-Pacific Region

The unique characteristics of patients with acute coronary syndrome in the Asia-Pacific region mean that international guidelines on the use of dual antiplatelet therapy (DAPT) cannot be routinely applied to these populations. Newer generation P2Y₁₂ inhibitors (i.e. ticagrelor and prasugrel) have demonstrated improved clinical outcomes compared with clopidogrel. However, low numbers of Asian patients participated in pivotal studies and few regional studies comparing DAPTs have been conducted. This article aims to summarise current evidence on the use of newer generation P2Y₁₂ inhibitors in Asian patients with acute coronary syndrome and provide recommendations to assist clinicians, especially cardiologists, in selecting a DAPT regimen. Guidance is provided on the management of ischaemic and bleeding risks, including duration of therapy, switching strategies and the management of patients with ST-elevation and non-ST-elevation MI or those requiring surgery. In particular, the need for an individualised DAPT regimen and considerations relating to switching, de-escalating, stopping or continuing DAPT beyond 12 months are discussed.

Loading doses of ticagrelor versus clopidogrel in preventing periprocedural myocardial infarction in Asian patients with acute coronary syndrome

BACKGROUND

Periprocedural myocardial infarction is a common complication following percutaneous coronary intervention. The present study was conducted with an aim to compare the safety and efficacy of loading doses of ticagrelor versus clopidogrel in preventing periprocedural myocardial infarction in Asian patients with acute coronary syndrome undergoing elective percutaneous coronary intervention.

METHODS

A total of 114 patients with acute coronary syndrome undergoing elective percutaneous coronary intervention were assigned to clopidogrel group (n = 57, the loading and maintenance doses were 300 and 75 mg qd for clopidogrel, and 300 and 100 mg qd for aspirin), or ticagrelor group (n = 57, the loading and maintenance doses were 180 and 90 mg bid for ticagrelor, and 300 and 100 mg qd for aspirin). Cardiac biomarkers were measured before, 8 hours, and 24 hours after percutaneous coronary intervention. The percutaneous coronary intervention-related periprocedural myocardial infarction was defined according to the fourth universal definition of myocardial infarction (2018).

RESULTS

The overall incidence of percutaneous coronary intervention-related periprocedural myocardial infarction was 21.1%. The ticagrelor group showed a significantly lower incidence of periprocedural myocardial infarction (12.3% vs 29.8%, p = 0.022) and numerically lower bleeding events (3.5% vs 8.8%, p = 0.242) as compared with clopidogrel group. No patient had major adverse cardiovascular events during the 1-month follow-up. The levels of high-sensitivity C-reactive protein did not differ significantly between the two groups (p > 0.05), indicating that the benefits of ticagrelor were not from its anti-inflammatory effects. Multivariable analysis showed that the use of ticagrelor (odds ratio: 0.50; 95% confidence interval: 0.29-0.87; p = 0.014) and number of stents (odds ratio: 2.75; 95% confidence interval: 1.25-6.06; p = 0.012) were independent predictors of periprocedural myocardial infarction.

CONCLUSION

Pretreatment with a loading dose of ticagrelor seems to be superior in reducing the incidence of percutaneous coronary intervention-related periprocedural myocardial infarction in Asian patients with acute coronary syndrome as compared with clopidogrel.