Rivaroxaban Does Not Alter Carotid Plaque Echolucency, Volume, or Neovascularisation

OBJECTIVE: This study investigated the effects of rivaroxaban on echolucency, volume, and neovascularisation in atherosclerotic carotid plaques compared with placebo in a randomised controlled study design.

METHODS: A double blinded, randomised, placebo controlled, single centre clinical trial was conducted. Results were reported according to the CONSORT guidelines. Patients with non-critical peripheral arterial disease were screened for asymptomatic carotid disease and included if a plaque in the carotid artery thicker than 2.5 mm was present. Patients were randomised to either rivaroxaban 2.5 mg twice daily or placebo in addition to aspirin and statins. Patients were followed for 12 months with evaluation visits at 3, 6, and 12 months, which included ultrasound (US) imaging, testing blood samples, and safety assessment. The primary outcome was change in US plaque echolucency as measured in grayscale median (GSM) over time. Secondary outcomes included changes in plaque volume and intraplaque neovascularisation (IPN). Safety and cardiovascular events were assessed at all visits. Plaque echolucency, volume, and neovascularisation were assessed with three dimensional US and two dimensional contrast enhanced US imaging. The most echolucent plaque by GSM in each patient identified at baseline was prospectively monitored (Clinical Trials Information System trial no. 2024-518539-13-00).

RESULTS: Initially, 62 patients were included, 31 received rivaroxaban and 31 received placebo. Final analyses included 28 patients in the rivaroxaban group and 29 patients in the placebo group. There were no differences between the groups in plaque GSM value, and GSM was unchanged over time in both groups. Further, no difference was found in the change in plaque volume or IPN score over time.

CONCLUSION: In patients with peripheral arterial disease and echolucent carotid plaques, treatment with rivaroxaban did not alter carotid plaque echolucency, plaque volume, or IPN.