BACKGROUND:

Patients’ responses to oral antiplatelet therapy are subject to variation. Bedside monitoring offers the opportunity to improve outcomes after coronary stenting by individualizing therapy.

METHODS:

We randomly assigned 2440 patients scheduled for coronary stenting at 38 centers to a strategy of platelet-function monitoring, with drug adjustment in patients who had a poor response to antiplatelet therapy, or to a conventional strategy without monitoring and drug adjustment. The primary end point was the composite of death, myocardial infarction, stent thrombosis, stroke, or urgent revascularization 1 year after stent implantation. For patients in the monitoring group, the VerifyNow P2Y12 and aspirin point-of-care assays were used in the catheterization laboratory before stent implantation and in the outpatient clinic 2 to 4 weeks later.

RESULTS:

In the monitoring group, high platelet reactivity in patients taking clopidogrel (34.5% of patients) or aspirin (7.6%) led to the administration of an additional bolus of clopidogrel, prasugrel, or aspirin along with glycoprotein IIb/IIIa inhibitors during the procedure. The primary end point occurred in 34.6% of the patients in the monitoring group, as compared with 31.1% of those in the conventional-treatment group (hazard ratio, 1.13; 95% confidence interval [CI], 0.98 to 1.29; P=0.10). The main secondary end point, stent thrombosis or any urgent revascularization, occurred in 4.9% of the patients in the monitoring group and 4.6% of those in the conventional-treatment group (hazard ratio, 1.06; 95% CI, 0.74 to 1.52; P=0.77). The rate of major bleeding events did not differ significantly between groups.

CONCLUSIONS:

This study showed no significant improvements in clinical outcomes with platelet-function monitoring and treatment adjustment for coronary stenting, as compared with standard antiplatelet therapy without monitoring. (Funded by Allies in Cardiovascular Trials Initiatives and Organized Networks and others; ARCTIC ClinicalTrials.gov number, NCT00827411.).