Early ambulance initiation versus in-hospital initiation of high dose clopidogrel in ST-segment elevation myocardial infarction

The Coronary Reperfusion Effect and Safety of Prehospital P2Y12 Inhibitor in Primary-PCI STEMI Patients: A Systematic Review and Meta-Analysis

BACKGROUND

The concept of early administration of P2Y12 inhibitor in ST-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI) is widely accepted, but whether prehospital administration results in greater coronary reperfusion remains unclear. Our study aims to analyze the benefit and safety of prehospital P2Y12 inhibitor compared to in-hospital P2Y12 inhibitor administration.

METHOD

Three databases (PubMed, EMBASE, and Cochrane Library) were searched from database inception to June 2023. We included all types of studies except for conference publications, abstract presentations, reviews, and case reports. The primary outcomes were pre-PCI TIMI flow grade 2-3 (TIMI = Thrombolysis in Myocardial Infarction) and major bleeding. The secondary outcomes included post-PCI TIMI flow grade 2-3, major adverse cardiac events (MACE), recurrent myocardial infarction (MI), and short-term (30-day) mortality.

RESULT

Eight individual studies with a total of 10823 patients were included in our meta-analysis. Compared with in-hospital P2Y12 inhibitor, prehospital P2Y12 inhibitor were associated with significantly higher rates of pre-PCI TIMI flow grade 2-3 (OR 1.32, 95% CI: 1.09-1.61, p = 0.005) and post-PCI TIMI flow grade 2-3 (OR 1.43, 95% CI: 1.04-1.97, p = 0.03), and a significantly lower risk of recurrent MI (OR 0.69, 95% CI: 0.49-0.96, p = 0.03). There were no significant difference in the risk of major bleeding (OR 1.00, 95% CI: 0.75-1.32, p = 0.98), MACE (OR 0.94, 95% CI: 0.70-1.25, p = 0.65), or short-term mortality (OR 0.87, 95% CI: 0.50-1.51, p = 0.61).

CONCLUSION

Prehospital P2Y12 inhibitor compared to in-hospital P2Y12 inhibitor is associated with a significantly higher rate of pre-PCI and post-PCI TIMI flow grade 2-3, a reduced risk of recurrent MI, and no increase in major bleeding in STEMI patients undergoing primary PCI.

The influence of pre-hospital medication administration in ST-elevation myocardial infarction patients on left ventricular ejection fraction and intra-hospital death

Introduction

Currently, invasive cardiology techniques are the preferred method of treatment for patients with ST-elevation myocardial infarction (STEMI). Improving the care of patients with STEMI is possible by minimizing the time that elapses from the onset of pain to the start of treatment. As studies indicate, early pharmacotherapy, especially with antiplatelet and anticoagulant medications, allows for their early effectiveness.

Aim

To assess the influence of early administration of antiplatelet (clopidogrel) and anticoagulant medications in the pre-hospital period in patients with ST-elevated myocardial infarction on the frequency of in-hospital deaths and on the left ventricular ejection fraction evaluated at hospital discharge.

Material and methods

In this study, a retrospective analysis of 573 patients hospitalized due to ST-segment elevation myocardial infarction in one of Krakow’s hospitals from January 2011 to December 2015 (excluding the whole of 2013) was used as a research method.

Results

As many as 97% of patients received pre-hospital pharmacotherapy, but only 46.0% of respondents received unfractionated heparin, and 19.2% received clopidogrel. The in-hospital mortality rate was 6.7%, but among patients prehospitally treated with clopidogrel and unfractionated heparin, the in-hospital mortality rate was 1.1%. Prehospital administration of clopidogrel significantly decreased the possibility of reduced left ventricular ejection fraction (OR = 0.27; 95% CI: 0.09–0.90).

Conclusions

Among pre-hospital procedures, only administration of a second antiplatelet drug (clopidogrel) significantly decreased the risk of reduced left ventricular ejection fraction, and administration of clopidogrel or heparin, or a combination of both, significantly decreased the risk of in-hospital death in patients with STEMI.

2019 Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology Guidelines on the Acute Management of ST-Elevation Myocardial Infarction: Focused Update on Regionalization and Reperfusion

Rapid reperfusion of the infarct-related artery is the cornerstone of therapy for the management of acute ST-elevation myocardial infarction (STEMI). Canada's geography presents unique challenges for timely delivery of reperfusion therapy for STEMI patients. The Canadian Cardiovascular Society/Canadian Association of Interventional Cardiology STEMI guideline was developed to provide advice regarding the optimal acute management of STEMI patients irrespective of where they are initially identified: in the field, at a non-percutaneous coronary intervention-capable centre or at a percutaneous coronary intervention-capable centre. We had also planned to evaluate and incorporate sex and gender considerations in the development of our recommendations. Unfortunately, inadequate enrollment of women in randomized trials, lack of publication of main outcomes stratified according to sex, and lack of inclusion of gender as a study variable in the available literature limited the feasibility of such an approach. The Grading Recommendations, Assessment, Development, and Evaluation system was used to develop specific evidence-based recommendations for the early identification of STEMI patients, practical aspects of patient transport, regional reperfusion decision-making, adjunctive prehospital interventions (oxygen, opioids, antiplatelet therapy), and procedural aspects of mechanical reperfusion (access site, thrombectomy, antithrombotic therapy, extent of revascularization). Emphasis is placed on integrating these recommendations as part of an organized regional network of STEMI care and the development of appropriate reperfusion and transportation pathways for any given region. It is anticipated that these guidelines will serve as a practical template to develop systems of care capable of providing optimal treatment for a wide range of STEMI patients.

P2Y12 receptor inhibition and effect of morphine in patients undergoing primary PCI for ST-segment elevation myocardial infarction

PRIVATE-ATLANTIC (P2Y12 Receptor Inhibition with VASP Testing using Elisa kit during the ATLANTIC study) is a pre-specified substudy of the randomised, double-blind ATLANTIC trial in patients with ST-segment elevation myocardial infarction, designed to help interpret the main trial results. The primary objective of ATLANTIC was to assess coronary reperfusion prior to percutaneous coronary intervention (PCI) with pre- vs in-hospital ticagrelor 180 mg loading dose (LD). PRIVATE-ATLANTIC assessed platelet inhibition in 37 patients by measurement of vasodilator-associated stimulated phosphoprotein (VASP) platelet reactivity index (PRI) and VerifyNow platelet reactivity units (PRU) before angiogram (T1), immediately after PCI (T2), 1 (T3), and 6 (T4) hours (h) after PCI, and before next study drug administration (T5). The median time difference between the two ticagrelor LD was 41 minutes. Platelet reactivity was unaffected at T1 when measured by VASP-PRI (89.8 vs 93.9% for pre- and in-hospital ticagrelor, respectively; p = 0.18) or PRU (239 vs 241; p = 0.82). Numerical differences were apparent at T2 and maximal at T3. Morphine administration significantly delayed onset of platelet inhibition at T3 (VASP-PRI 78.2 vs 23.4% without morphine; p = 0.0116) and T4 (33.1 vs 11.0%; p = 0.0057). In conclusion, platelet inhibition in ATLANTIC was unaffected by pre-hospital ticagrelor administration at the time of initial angiogram due to the short transfer delay. The maximum difference in platelet inhibition was detected 1 h after PCI (T3). Morphine administration was associated with delayed onset of action of ticagrelor and appeared more important than timing of ticagrelor administration.

Impact of acute infarct-related artery patency before percutaneous coronary intervention on 30-day outcomes in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention in the EUROMAX trial

AIMS

Early infarct-related artery patency has been associated with improved outcomes in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention. However, it is unknown whether this relationship persists in contemporary practice with pre-hospital initiation of treatment, use of novel P2Y₁₂ inhibitors and frequent use of drug-eluting stents. The purpose of the study was to determine the impact of early infarct-related artery patency on outcomes in the contemporary EUROMAX trial.

METHODS AND RESULTS

A total of 2218 patients were enrolled. The current analysis was done on 1863 patients who underwent percutaneous coronary intervention and had infarct-related artery patency data. Thirty-day outcomes were compared according to infarct-related artery flow before percutaneous coronary intervention (Thrombolysis in Myocardial Infarction (TIMI) flow 0/1 vs. TIMI flow 2/3), and interaction with antithrombotic strategy was examined. A patent infarct-related artery (TIMI flow 2/3) was present in 707 patients (37.9%) and was associated with a higher rate of final TIMI 3 flow grade (98.9 vs. 92.6%; p<0.001). At 30 days, a patent infarct-related artery was associated with lower rates of cardiac death (1.3% vs. 2.9%; p=0.026) and the composite of death or myocardial infarction (2.7% vs. 4.6%; p=0.039). There were no interactions between antithrombotic treatment and the impact of infarct-related artery patency on cardiac death, myocardial infarction, or the composite of death or myocardial infarction (Breslow-Day interaction p-values of 0.21, 0.33 and 0.46, respectively).

CONCLUSION

Despite evolution in primary percutaneous coronary intervention strategies, early infarct-related artery patency is still associated with higher procedural success and improved clinical outcomes. The choice of antithrombotic strategy did not interact with the benefits of a patent infarct-related artery at presentation.

Switching from Clopidogrel to Prasugrel in patients undergoing PCI: A meta-analytic overview

Despite the demonstrated benefits of Prasugrel, a new generation thienopyridine, in the prevention of thrombotic complications after percutaneous coronary interventions (PCI) for Acute Coronary Syndromes (ACS), its use is still precluded to those many patients arriving to the cath lab pre-treated with Clopidogrel. Conclusive data on the strategy of switching from Clopidogrel to Prasugrel are still missing, therefore we aimed to perform a meta-analysis of current studies evaluating the safety and efficacy of switching from Clopidogrel to Prasugrel (PS) as compared to a standard thienopyridine therapy with Clopidogrel or Prasugrel in patients undergoing PCI. Literature archives and main scientific sessions' abstracts were scanned for studies comparing a switching strategy from Clopidogrel to Prasugrel vs. Prasugrel or Clopidogrel. Primary efficacy endpoint was overall mortality. Secondary endpoints were: non-fatal myocardial infarction and definite/probable stent thrombosis. Safety endpoint was the rate of major bleedings according to a per-protocol definition. A total of 12 studies, involving 3956 patients, were included. Among them, 1396 patients (35.3%), received Prasugrel after a Clopidogrel treatment (PS), while 2560 (64.7%) received either Prasugrel or Clopidogrel. The switch from Clopidogrel to Prasugrel was in the majority of the studies periprocedural. The mortality was numerically lower, but not statistically significant, in the PS group as compared with patients who did not switch (1.7% vs. 3.8%, OR [95% CI] = 0.68 [0.40,1.15], p = 0.15, phet = 0.61), without any relationship with patients' risk profile (r = -0.68 [-2.09, 0.73], p = 0.35). Similar results were obtained for secondary efficacy endpoints and at sensitivity analysis in the majority of subgroups evaluated. Moreover, the PS strategy did not increase major bleedings as compared with standard therapy (1.4% vs. 2.5%, OR [95% CI = 0.70 [0.39, 1.25], p = 0.23, phet = 0.6). The present meta-analysis confirms that, among patients undergoing PCI, switching from Clopidogrel to Prasugrel may be safely performed and therefore should be encouraged among patients eligible to Prasugrel.