Evaluation of antiplatelet effects of a modified protocol by platelet aggregation in patients undergoing "one-stop" hybrid coronary revascularization

Abstract

"One-stop" hybrid coronary revascularization has emerged to be a reliable and attractive alternative for selected patients with multivessel coronary artery disease. However, the optimal antiplatelet regimen of the one-stop hybrid procedure still remains controversial. We modified the antiplatelet protocol in order to reduce the risk of perioperative bleeding and maximally inhibit platelet activity. This study sought to investigate whether the inhibition of platelet activity by this modified antiplatelet protocol is comparable with the conventional protocol widely used and recommended in percutaneous coronary interventions (PCI). Twenty three patients undergoing one-stop hybrid procedure and 20 patients undergoing conventional PCI were enrolled in this prospective study. The modified antiplatelet protocol included perioperative use of aspirin; clopidogrel was administered immediately before PCI with a 300 mg loading dose, followed by a maintenance dose of 75 mg/day for 12 months. Blood samples were obtained before the operation and 2 hours, day 1 and day 3 after operation. Platelet aggregation was induced with: 1) arachidonic acid (AA) (final concentration 0.5 mmol/L) to assess the efficacy of aspirin; 2) adenosine diphosphate (ADP) (final concentration 10 micromol/L) to assess the specific efficacy of clopidogrel. Platelet counts were statistically lower in the hybrid group than in the PCI control group (p = 0.0018) on day 1 after operation. AA-induced platelet aggregation increased significantly in comparison with the preoperative baseline values (p = 0.0079) and the PCI control group (p = 0.0023) on day 1 after operation. ADP-induced platelet aggregation gradually decreased in the hybrid group, and achieved similar platelet inhibition with the PCI group on 2 hours and day 1 after operation. No major adverse clinical events such as death, perioperative myocardial infarction, stent thrombosis or reoperation for bleeding occurred in both groups within 30 days after procedure. These results demonstrate that our modified antiplatelet therapy can sufficiently inhibit platelet activity similarly as the conventional protocol for PCI early after operation. Thus, this modified protocol, with continuous use of aspirin and intraoperative administration of loading dose clopidogrel, might be a safe and effective antiplatelet strategy for the one-stop hybrid coronary revascularization.