Aspirin-free antiplatelet regimens after PCI: insights from the GLOBAL LEADERS trial and beyond

Historically, aspirin has been the primary treatment for the prevention of ischaemic events in patients with coronary artery disease. For patients undergoing percutaneous coronary intervention (PCI) standard treatment has been 12 months of dual antiplatelet therapy (DAPT) with aspirin and clopidogrel, followed by aspirin monotherapy; however, DAPT is undeniably associated with an increased risk of bleeding. For over a decade novel P2Y₁₂ inhibitors, which have increased specificity, potency, and efficacy have been available, prompting studies which have tested whether these newer agents can be used in aspirin-free antiplatelet regimens to augment clinical benefits in patients post-PCI. Among these studies, the GLOBAL LEADERS trial is the largest by cohort size, and so far has provided a wealth of evidence in a variety of clinical settings and patient groups. This article summarizes the state-of-the-art evidence obtained from the GLOBAL LEADERS and other trials of aspirin-free strategies.

Effect of bivalirudin on neointimal hyperplasia and endothelial proliferation in rabbit

BACKGROUND

The aim of this study was to investigate the effects of bivalirudin on endothelial cell proliferation and neointimal hyperplasia in a rabbit carotid artery model.

METHODS

"New Zealand rabbits (n = 12)" weighing 2-3 kg were randomly divided into two groups. Arteriotomy was performed to the rabbit carotid artery and closed with continuous suture technique. Group B (n = 6) as a control group received 150 U/kg heparin sodium; however, group A (n = 6) was given 0.75 mg/kg bivalirudin i.v. bolus and infusion 1.75 mg/kg/hour (B01AE06-Bivalirudin 250 mg) during perioperation period. At the end of the 28th day, the carotid artery segment was excised and evaluated histologically.

RESULTS

All histological and immune staining analyzes were performed by two blind researchers in the treatment of rabbits. In the control group rabbit carotid artery sections, tunica intima was observed to thicken. In the bivalirudin group, intimal hyperplasia was less observed compared to the control group. No significant difference was observed between groups in tunica media thickness. Lumen diameter and lumen area were found to be wider in the experimental group. P value was found to be less than 0.05.

CONCLUSION

Our study demonstrates that bivalirudin significantly affects and prevents neointimal hyperplasia and endothelial cell proliferation.