Ticagrelor-based antiplatelet regimens in patients treated with coronary artery bypass grafting: a meta-analysis of randomized controlled trials

OBJECTIVES

The optimal antiplatelet strategy in patients undergoing CABG remains unclear. This is the first meta-analysis investigating the clinical outcomes associated with ticagrelor-based antiplatelet regimens in patients receiving CABG.

METHODS

Relevant scientific databases were searched for studies investigating antiplatelet regimens after CABG from inception until April 1, 2019. Studies which randomly assigned CABG patients to either ticagrelor-based or control antiplatelet regimens were eligible. The primary outcome of this analysis was all-cause death. The main secondary outcome was MI. Other outcomes of interest were cardiac death, major adverse cardiac events, stroke and bleeding. This study is registered with PROSPERO, number CRD42019122192.

RESULTS

Five trials comprising 3996 patients (2002 assigned to ticagrelor-based and 1994 to control antiplatelet regimens) were eligible for quantitative synthesis. The median follow-up was 12 months. Control antiplatelet regimens consisted of either aspirin or clopidogrel or both. As compared to control, ticagrelor-based regimens reduced the risk of all-cause death [0.61 (0.43-0.87); P = 0.007], cardiac death [0.58 (0.39-0.86); P = 0.007] and major adverse cardiac events [0.79 (0.63-0.98); P = 0.03], without difference in the risk of MI [0.76 (0.50-1.18); P = 0.22], stroke [0.99 (0.56-1.78); P = 0.98] or bleeding [1.04 (0.95-1.14); P = 0.41]. There was a treatment effect modification for the primary outcome associated with trials enrolling predominantly patients with acute coronary syndrome (P for interaction = 0.038).

CONCLUSIONS

In patients receiving CABG, ticagrelor-based regimens reduce mortality and major adverse cardiac events without excess bleeding risk as compared with aspirin monotherapy or the combination of aspirin and clopidogrel. The benefit of ticagrelor-based regimens is more relevant in those studies enrolling predominantly patients with acute coronary syndrome. These findings require further confirmation in randomized trials focused on this subset of patients and powered for clinical outcomes.

Antithrombotic treatment after coronary artery bypass graft surgery: systematic review and network meta-analysis

OBJECTIVE

To assess the effects of different oral antithrombotic drugs that prevent saphenous vein graft failure in patients undergoing coronary artery bypass graft surgery.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

Medline, Embase, Web of Science, CINAHL, and the Cochrane Library from inception to 25 January 2019. ELIGIBILITY CRITERIA: for selecting studies Randomised controlled trials of participants (aged ≥18) who received oral antithrombotic drugs (antiplatelets or anticoagulants) to prevent saphenous vein graft failure after coronary artery bypass graft surgery.

MAIN OUTCOME MEASURES

The primary efficacy endpoint was saphenous vein graft failure and the primary safety endpoint was major bleeding. Secondary endpoints were myocardial infarction and death.

RESULTS

This review identified 3266 citations, and 21 articles that related to 20 randomised controlled trials were included in the network meta-analysis. These 20 trials comprised 4803 participants and investigated nine different interventions (eight active and one placebo). Moderate certainty evidence supports the use of dual antiplatelet therapy with either aspirin plus ticagrelor (odds ratio 0.50, 95% confidence interval 0.31 to 0.79, number needed to treat 10) or aspirin plus clopidogrel (0.60, 0.42 to 0.86, 19) to reduce saphenous vein graft failure when compared with aspirin monotherapy. The study found no strong evidence of differences in major bleeding, myocardial infarction, and death among different antithrombotic therapies. The possibility of intransitivity could not be ruled out; however, between-trial heterogeneity and incoherence were low in all included analyses. Sensitivity analysis using per graft data did not change the effect estimates.

CONCLUSIONS

The results of this network meta-analysis suggest an important absolute benefit of adding ticagrelor or clopidogrel to aspirin to prevent saphenous vein graft failure after coronary artery bypass graft surgery. Dual antiplatelet therapy after surgery should be tailored to the patient by balancing the safety and efficacy profile of the drug intervention against important patient outcomes.

STUDY REGISTRATION

PROSPERO registration number CRD42017065678.