Juan Ocampo Míguez

OBJECTIVES: The REAC-TAVI (Assessment of platelet REACtivity after Transcatheter Aortic Valve Implantation) trial enrolled patients with aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) pre-treated with aspirin + clopidogrel, aimed to compare the efficacy of clopidogrel and ticagrelor in suppressing high platelet reactivity (HPR) after TAVI. BACKGROUND: Current recommendations support short-term use of aspirin + clopidogrel for patients with severe AS undergoing TAVR despite the lack of compelling evidence. METHODS: reaction units (PRU) ≥208. Patients with HPR before TAVR were randomized to either aspirin + ticagrelor or aspirin + clopidogrel for 3 months. Patients without HPR continued with aspirin + clopidogrel (registry cohort). The primary endpoint was non-HPR status (PRU <208) in ≥70% of patients treated with ticagrelor at 90 days post-TAVR. RESULTS: A total of 68 patients were included. Of these, 48 (71%) had HPR (PRU 273 ± 09) and were randomized to aspirin + ticagrelor (n = 24, PRU 277 ± 08) or continued with aspirin + clopidogrel (n = 24, PRU 269 ± 49). The remaining 20 patients (29%) without HPR (PRU 133 ± 12) were included in the registry. Overall, platelet reactivity across all the study time points after TAVR was lower in patients randomized to ticagrelor compared with those treated with clopidogrel, including those enrolled in the registry (p < 0.001). The primary endpoint was achieved in 100% of patients with ticagrelor compared with 21% with clopidogrel (p < 0.001). Interestingly, 33% of clopidogrel responder patients at baseline developed HPR status during the first month after TAVR. CONCLUSIONS: HPR to clopidogrel is present in a considerable number of patients with AS undergoing TAVR. Ticagrelor achieves a better and faster effect, providing sustained suppression of HPR to these patients. (Platelet Reactivity After TAVI: A Multicenter Pilot Study [REAC-TAVI]; NCT02224066).

BACKGROUND: The effectiveness of oral anticoagulation (OAC) or dual antiplatelet therapy (DAPT) in reducing subclinical brain infarcts after transcatheter aortic valve implantation (TAVI) remains unclear. AIMS: We aimed to compare the efficacy of DAPT versus OAC in preventing cerebral microembolism during the first 3 months post-TAVI, assessed by diffusion-weighted magnetic resonance imaging (DW-MRI). METHODS: Patients with aortic stenosis and no indication for OAC were randomly assigned to receive either OAC (acenocoumarol) or DAPT (aspirin+clopidogrel) for 3 months post-TAVI. Brain DW-MRI was performed at baseline (0-3 days pre-TAVI) and at 6 and 90 days post-TAVI. The primary objective was the proportion of patients with new cerebral emboli on DW-MRI at 6 and 90 days. RESULTS: Of the 123 patients included in the study, 3.3% had new cerebral emboli on the baseline MRI prior to TAVI. At 6 days post-TAVI, new cerebral emboli were observed in 81.4% of OAC patients versus 69.8% of DAPT patients (p=0.209), and at 90 days, in 8.0% versus 8.2%, respectively (p=0.879). However, DAPT patients had a lower mean total emboli volume at 6 days (265.9 mm³ vs 303.4 mm³; p=0.019) and cumulatively at 6+90 days (266.45 mm³ vs 331.10 mm³; p=0.008). CONCLUSIONS: In patients without an indication for OAC, an OAC strategy for 3 months post-TAVI did not show any benefit over an antiplatelet strategy in preventing cerebral microembolism. Patients treated with DAPT showed a lower mean volume of brain damage on DW-MRI during the 90 days following TAVI compared to those treated with acenocoumarol.