Comparison of Ticagrelor Versus Clopidogrel on Cerebrovascular Microembolic Events and Platelet Inhibition during Transcatheter Aortic Valve Implantation

Abstract

The impact of the antiplatelet regimen and the extent of associated platelet inhibition on cerebrovascular microembolic events during transcatheter aortic valve implantation (TAVI) are unknown. Our aim was to evaluate the effects of ticagrelor versus clopidogrel and of platelet inhibition on the number of cerebrovascular microembolic events in patients undergoing TAVI. Patients scheduled for TAVI were randomized previous to the procedure to either aspirin and ticagrelor or to aspirin and clopidogrel. Platelet inhibition was expressed in P2Y12 reaction units (PRU) and percentage of inhibition. High intensity transient signals (HITS) were assessed with transcranial Doppler (TCD). Safety outcomes were recorded according to the VARC-2 definitions. Among 90 patients randomized, 6 had an inadequate TCD signal. The total number of procedural HITS was lower in the ticagrelor group (416.5 [324.8, 484.2]) (42 patients) than in the clopidogrel group (723.5 [471.5, 875.0]) (42 patients), p <0.001. After adjusting for the duration of the procedure, diabetes, extra-cardiac arteriopathy, BMI, hypertension, aortic valve calcium content, procedural ACT, and pre-implantation balloon valvuloplasty, patients on ticagrelor had on average 256.8 (95% CI: [-335.7, -176.5]) fewer total procedural HITS than patients on clopidogrel. Platelet inhibition was greater with ticagrelor 26 [10, 74.5] PRU than with clopidogrel 207.5 (120 to 236.2) PRU, p <0.001, and correlated significantly with procedural HITS (r = 0.5, p <0.05). In conclusion, ticagrelor resulted in fewer procedural HITS, compared with clopidogrel, in patients undergoing TAVI, while achieving greater platelet inhibition.