High Platelet Reactivity Tied to Ischemic, Bleeding Outcomes
Findings based on two-year follow-up after drug-eluting stent implantation
TUESDAY, Aug. 15, 2017 (HealthDay News) -- There is a strong relationship between high on-clopidogrel platelet reactivity and two-year ischemic and bleeding outcomes after drug-eluting stent implantation, according to a study published online Aug. 2 in JACC: Cardiovascular Interventions.
Thomas D. Stuckey, M.D., from Cone Health in Greensboro, N.C., and colleagues analyzed two-year outcomes in the Assessment of Dual AntiPlatelet Therapy with Drug-Eluting Stents study, which followed 8,582 patients undergoing routine platelet function testing following percutaneous coronary intervention with drug-eluting stents (2008 to 2010).
The researchers found that 46.3 percent of patients were on dual antiplatelet therapy at two years without discontinuation. Ninety-two patients (1.07 percent) had definite or probable stent thrombosis at two years. High platelet reactivity on clopidogrel was independently associated with definite or probable stent thrombosis in continuously treated patients (hazard ratio [HR], 2.09; 95 percent confidence interval [CI], 1.29 to 3.82; P = 0.006). Other associations included myocardial infarction (HR, 1.33; 95 percent CI, 1.04 to 1.71; P = 0.02), freedom from clinically relevant bleeding (HR, 0.78; 95 percent CI, 0.64 to 0.94; P < 0.01), and all-cause mortality (adjusted HR, 1.35; 95 percent CI, 1.00 to 1.84, P = 0.05).
"Aspirin hypo-responsiveness in low-risk patients maintained on aspirin monotherapy beyond one year did not predict late events. High platelet reactivity in high-risk patients maintained on dual antiplatelet therapy was independently associated with outcomes to two years," the authors write. "Future studies evaluating the long-term use of adenosine diphosphate inhibition should incorporate individualized patient selection to optimize the trade-off between ischemic event reduction and bleeding."
Several authors disclosed financial ties to medical device and pharmaceutical companies, several of which funded the study.