Conference Coverage

Clopidogrel flunks platelet reactivity control test in TAVI



– For antithrombotic therapy after transcatheter aortic valve implantation (TAVI), ticagrelor plus aspirin may be a better strategy than clopidogrel plus aspirin even though the latter combination is guideline recommended, according to a late-breaking, randomized study presented at CRT 2018 sponsored by the Cardiovascular Research Institute at Washington Hospital Center.

Unlike the ticagrelor regimen, which did deliver the goal antiplatelet effect for all 3 months of the study, “clopidogrel did not achieve adequate platelet inhibition before or after TAVI in most patients,” reported Victor A. Jimenez Diaz, MD, a cardiologist at University Hospital, Vigo, Spain.

Ted Bosworth/MDedge News

Dr. Victor A. Jimenez Diaz

This investigator-initiated, multicenter study, called the REAC TAVI trial, was relatively small and was limited to an evaluation of platelet reactivity, but the data suggest that a “large, randomized trial powered for clinical endpoints is urgently needed,” according to Dr. Jimenez Diaz.

The current American Heart Association/American College of Cardiology guidelines label the clopidogrel/aspirin combination for the first 6 months after TAVI “reasonable,” but Dr. Jimenez Diaz said that the value of this combination over other antiplatelet strategies has not been supported by a randomized clinical trial. The known variability in response to clopidogrel is among the reasons such data are needed.

Thrombotic and hemorrhagic complications are frequent after TAVI, making choice of antithrombotic treatment an important consideration for improving outcomes, according to Dr. Jimenez Diaz. The aim of the REAC TAVI trial was to evaluate whether ticagrelor provides a more consistent antiplatelet effect than clopidogrel for TAVI patients, which was undertaken at seven participating centers in Spain.

A total of 65 candidates for TAVI were enrolled in this study. The key exclusion criterion was chronic oral anticoagulation therapy. In a baseline assessment, patients in the study, all of whom were on 75 mg clopidogrel plus aspirin, were evaluated for high on-treatment platelet reactivity (HTPR), defined as a score of at least 208 platelet reaction units (PRU) on a standard assay.

The 46 (71%) patients found to have HTPR were randomized to 90 mg ticagrelor twice daily plus aspirin or to remain on the clopidogrel/aspirin combination. Unlike those with HTPR, in whom the mean PRU was 274 units, all of the patients without HTPR, who had a mean PRU of 134 units, remained on the baseline dual antiplatelet therapy. The study was open label.

Next Article: