Absence of differential effect of ticagrelor versus prasugrel maintenance dose on endothelial function in patients with stable coronary artery disease.

ABSTRACT

BACKGROUND: Endothelial function may be improved by ticagrelor through adenosine-mediated mechanisms. We aimed to assess the effect of ticagrelor versus prasugrel on endothelial function in patients with stable coronary artery disease (CAD). METHODS: In a prospective, randomized, crossover study, 22 stable CAD patients under prasugrel 10 mg once daily maintenance dose (MD) for at least 3 months were randomized to either ticagrelor 90 mg twice daily or prasugrel 10 mg once daily for 15 days with a direct treatment-crossover for another 15 days. Endothelial function was assessed by peripheral arterial tonometry (EndoPAT 2000 system, Itamar Medical, Caesarea, Israel) at Day 0 (randomization), Day 15, and Day 30. Reactive Hyperemia Index (RHI) was calculated by using an automated software, and endothelial dysfunction (ED) was defined as RHI <1.67. RHI at the end of the two treatment periods did not differ between ticagrelor and prasugrel MD treatments. Least squares estimates (95% confidence interval) were 1.78 (1.58-1.99) versus 1.88 (1.67-2.08), with a fixed estimate of -0.099 (95% CI -0.45 to 0.25) for the difference between them (p = 0.5). ED rate did not differ significantly between ticagrelor and prasugrel (45.5% vs 45.5%, p = 0.6). CONCLUSIONS: In CAD patients, we have failed to find evidence of alteration of endothelial function following ticagrelor compared to prasugrel MD treatment, as assessed by peripheral arterial tonometry. CLINICALTRIALS. GOV UNIQUE IDENTIFIER NCT01957540.