Antiplatelet Treatment with Ticagrelor vs. Clopidogrel in Patients with Chronic Coronary Syndrome

Achieving rapid and maximum inhibition of platelet aggregation can reduce complications related to scheduled percutaneous coronary intervention (PCI) in chronic coronary syndromes (CCS). Over the last few decades, the optimal timing for initiating P2Y12 inhibitors and their appropriate dosage have been the subject of numerous studies; however, they have not been clearly established yet. Higher loading doses or reloading in patients previously treated with clopidogrel can lead to higher and faster levels of platelet anti-aggregation, but they have not translated into a reduction in adverse events.

The ALPHEUS (Assessment of Loading with P2Y12 Inhibitor Ticagrelor or Clopidogrel to Halt Ischemic Events in Patients Undergoing Elective Coronary Stenting) study compared the effect of ticagrelor vs. clopidogrel on the reduction of periprocedural myocardial infarction (MI) in stable coronary patients undergoing PCI.

The aim of this multicenter, randomized study was to assess the efficacy and safety of ticagrelor compared with clopidogrel in patients with or without chronic clopidogrel treatment undergoing high-risk elective PCI.

The primary efficacy endpoint (efficacy PEP) was the rate of periprocedural MI and major myocardial injury. The primary safety endpoint (safety PEP) was major bleeding. The secondary endpoint (SEP) was a composite of death, MI, stroke, transient ischemic attack (TIA), and bleeding at 48 hours and at 30 days.

The study included a total of 1182 patients, 42% of whom were on prior clopidogrel treatment. These patients were older, with more comorbidities; complex PCI was more frequent in this group. The efficacy PEP was less frequent in the group without prior clopidogrel treatment compared with the group on chronic clopidogrel treatment (32.8% vs. 40.0%; odds ratio [OR]: 0.73; 95% confidence interval [CI]: 0.60-0.88). There were no differences in the risk of death, MI, stroke, or TIA. The use of ticagrelor did not reduce periprocedural injury or the risk of adverse events.

Conclusion

Patients undergoing elective PCI without prior clopidogrel treatment have a lower risk of periprocedural complications compared with patients on chronic clopidogrel treatment. Early events and outcomes were not reduced with the use of ticagrelor. These results support the use of clopidogrel as the standard treatment in elective PCI, both in patients with and without chronic clopidogrel treatment.