Background: Platelets play an important role in inflammation. Inhibitors of the P2Y12 receptor, which is involved in platelet activation, may have a direct effect on carotid atherosclerotic plaque inflammation.
Hypothesis: We compared the effects of clopidogrel and ticagrelor therapy for carotid atherosclerotic plaque inflammation using 18 F-fluorodeoxyglucose ( 18 FDG) positron emission tomography (PET) imaging.
Methods: Fifty patients with acute coronary syndrome and ≥1 18 FDG uptake in the carotid artery (target-to-background ratio [TBR] ≥1.6) were randomized to either clopidogrel or ticagrelor groups. Of these, 46 completed PET examinations at baseline and at 6 months. The primary endpoint was the percent change in TBR of the index vessel at the most diseased segment (MDS).
Results: Baseline characteristics were similar between the 2 groups. At 6-month follow-up, low-density lipoprotein cholesterol and C-reactive protein significantly decreased in both groups (P < 0.001). The TBR of the index vessel and aorta significantly decreased in both groups (P < 0.01). The percent change in the MDS TBR of the index vessel was numerically but not significantly lower in the clopidogrel group than in the ticagrelor group (-9.5 ± 14.6% vs -13.5 ± 19.3%; P = 0.427). Likewise, the percent change in the whole-vessel TBR of the index vessel was not different between the 2 groups (P = 0.166). Similar findings were observed for changes in the MDS TBR (P = 0.412) or whole-vessel TBR of the aorta (P = 0.363).
Conclusions: Carotid atherosclerotic plaque inflammation significantly decreases to a similar degree following 6 months of either clopidogrel or ticagrelor treatment.
Keywords: Imaging; P2Y12 inhibitors; clopidogrel; plaque inflammation; positron emission tomography; ticagrelor.
© 2016 Wiley Periodicals, Inc.