β-blockers are associated with decreased leucocyte-platelet aggregate formation and lower residual platelet reactivity to adenosine diphosphate after angioplasty and stenting

Background The beneficial effects of β-blockers on the long-term prognosis of patients with cardiovascular disease may in part be attributable to decreased platelet activation. In this prospective cohort study, we sought to investigate the impact of concomitant β-blocker therapy on sensitive markers of platelet activation and aggregation. Materials and methods Monocyte–platelet (MPA) and neutrophil–platelet aggregate (NPA) formation in vivo and in response to the platelet agonist adenosine diphosphate (ADP) were determined by flow cytometry in 258 patients undergoing angioplasty and stenting. On-treatment residual platelet reactivity to ADP was assessed by multiple electrode aggregometry (MEA). Results One hundred seventy-five patients of the study population (67·8%) received β-blockers. Treatment with β-blockers was associated with significantly lower MPA and NPA formation in vivo and in response to ADP compared to patients without β-blockers (all P ≤ 0·01). The inverse associations of MPA and NPA formation with β-blocker therapy remained statistically significant after adjustment for differences in patient characteristics by multivariate linear regression analyses (all P < 0·05). Moreover, high levels of MPA in response to ADP as well as high levels of NPAin vivo and in response to ADP were significantly less frequent in patients with β-blocker treatment (all P < 0·05). Finally, on-treatment residual platelet reactivity to ADP by MEA was significantly lower in patients receiving β-blockers (P = 0·005). Conclusion β-Blockers are associated with decreased leucocyte–platelet aggregate formation and lower on-treatment residual platelet reactivity to ADP in patients with dual antiplatelet therapy following angioplasty and stenting.