Upstream clopidogrel, prasugrel, or ticagrelor for patients treated with primary angioplasty: Results of an angiographic randomized pilot study

Effect of prasugrel versus ticagrelor on coronary microcirculation in patients undergoing pharmacoinvasive strategy - acute and short-term results

INTRODUCTION

Both ticagrelor and prasugrel are class I recommendations for treatment of ST-elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI) [ 1 ]. But clinical outcomes with the two drugs are conflicting which might be due to differential effects on coronary microcirculation. No study to date had compared the effects of prasugrel or ticagrelor on coronary microcirculation in patients undergoing pharmacoinvasive PCI (pPCI).

AIM AND OBJECTIVE

To compare the effects of prasugrel and ticagrelor on coronary microcirculation in STEMI patients undergoing pPCI as assessed by Myocardial Blush Grade (MBG). The secondary aim was to assess flow in the infarct-related artery by corrected thrombolysis in myocardial infarction (TIMI) frame count (cTFC) and whether a differential effect if detected on coronary microcirculation translated in improvement in left ventricular ejection fraction assessed at 6 months.

MATERIAL AND METHODS

A total of 240 patients with STEMI were evaluated in this open-label randomized control trial who initially underwent thrombolysis and later PCI (from 24 to 48 h) post-successful thrombolysis. The study subjects were randomized to receive either ticagrelor ( n  = 120) or prasugrel ( n  = 120) in 1 : 1 ratio 2 h prior to elective PCI. Patients underwent PCI according to standard protocol and post-procedure cTFC and MBG were compared. Patients were also followed up for 6 months to compare ejection fractions in both groups. We also assessed the effect of the two drugs on bleeding complications during hospitalization and over 6-month follow-up period.

RESULTS

There were no significant differences between the two groups with respect to baseline characteristics. Prasugrel administration resulted in higher MBG Grade 3 (50.86% vs 33.89%, P  = 0.012) and lower cTFC (17.14 ± 4.08 vs 19.3 ± 4.06, P  < 0.01). Improvement in ejection fraction was significantly higher with prasugrel compared to ticagrelor (10.29% ± 15.2 vs 4.66% ± 13.5, P  = 0.003). Bleeding events at 6 months follow-up according to TIMI classification were similar in both the groups (11.86% vs 6.9%, P  = 0.39).

CONCLUSION

Prasugrel produces greater improvement in coronary microcirculation than Ticagrelor resulting in improved myocardial salvage in patients of STEMI undergoing pPCI.

Ticagrelor vs. clopidogrel for coronary microvascular dysfunction in patients with STEMI: a meta-analysis of randomized controlled trials

Purpose

Approximately half of ST-segment elevation myocardial infarction (STEMI) patients who undergo revascularization present with coronary microvascular dysfunction. Dual antiplatelet therapy, consisting of aspirin and a P2Y12 inhibitor (e.g., clopidogrel or ticagrelor), is recommended to reduce rates of cardiovascular events after STEMI. The present study performed a pooled analysis of randomized controlled trials (RCTs) to compare effects of ticagrelor and clopidogrel on coronary microcirculation dysfunction in STEMI patients who underwent the primary percutaneous coronary intervention.

Methods

The PubMed, Embase, Cochrane Library, and Web of Science databases were searched for eligible RCTs up to September 2022, with no language restriction. Coronary microcirculation indicators included the corrected thrombolysis in myocardial infarction (TIMI) frame count (cTFC), myocardial blush grade (MBG), TIMI myocardial perfusion grade (TMPG), coronary flow reserve (CFR), and index of microcirculatory resistance (IMR).

Results

Seven RCTs that included a total of 957 patients (476 who were treated with ticagrelor and 481 who were treated with clopidogrel) were included. Compared with clopidogrel, ticagrelor better accelerated microcirculation blood flow [cTFC = -2.40, 95% confidence interval (CI): -3.38 to -1.41, p < 0.001] and improved myocardial perfusion [MBG = 3, odds ratio (OR) = 1.99, 95% CI: 1.35 to 2.93, p < 0.001; MBG ≥ 2, OR = 2.57, 95% CI: 1.61 to 4.12, p < 0.001].

Conclusions

Ticagrelor has more benefits for coronary microcirculation than clopidogrel in STEMI patients who undergo the primary percutaneous coronary intervention. However, recommendations for which P2Y12 receptor inhibitor should be used in STEMI patients should be provided according to results of studies that investigate clinical outcomes.

Effect of preoperative loading dose ticagrelor and clopidogrel on no-reflow phenomenon during intervention in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention: a systematic review and meta-analysis

BACKGROUND

Previous studies have shown that ticagrelor is more effective than clopidogrel in platelet inhibition. However, this conclusion remains controversial. Therefore, we performed this meta-analysis to assess the effect of preoperative loading dose ticagrelor and clopidogrel on no-reflow (NRF) during intervention in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention (PPCI).

MATERIALS AND METHODS

Randomized controlled trials and observational studies were reviewed. The retrieval time was limited from inception to October 1, 2017. The retrieved databases included PubMed, Embase, the Cochrane Library, Web of Science, CBM, CNKI, the VIP database, and the Wang Fang database. RevMan 5.3 software was used for data analysis.

RESULTS

Fourteen randomized controlled trials and one observational study, including 4,162 patients, were included. In these articles, 1,521 patients were in the ticagrelor group (180 mg) and 2,641 patients were in the clopidogrel group (600 mg). The meta-analysis showed that compared with clopidogrel group, preoperative loading dose ticagrelor: 1) significantly reduced the incidence of NRF during PPCI (95% confidence interval [CI]: 0.15, 0.39, P<0.05) as well as the level of postoperative corrected thrombolysis in myocardial infarction frame count (95% CI: -8.89, -6.91, P<0.05); 2) significantly reduced the incidence of major adverse cardiovascular events during hospitalization, including 30 and 180 days after PPCI (95% CI: 0.41, 0.82, P<0.05; 95% CI: 0.15, 0.46, P<0.05, respectively); and 3) significantly improved thrombolysis in myocardial infarction flow after PPCI (95% CI: 1.40, 2.45, P<0.05). No significant difference was observed in terms of bleeding events within 30 and 180 days after PPCI (95% CI: 0.71, 1.54, P=0.82; 95% CI: 0.81, 3.19, P=0.18, respectively).

CONCLUSION

Compared with clopidogrel, loading dose ticagrelor effectively reduced both the occurrence of NRF during PPCI and the incidence of major adverse cardiovascular event in patients with ST-segment elevation myocardial infarction undergoing PPCI. Furthermore, it did not increase the risk of bleeding after PPCI.