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.