In the COMPASS trial, low-dose rivaroxaban with aspirin improved cardiovascular outcomes in patients with atherosclerotic cardiovascular disease (ASCVD). We aimed to assess the potential clinical implications of this therapy in a generalizable population.

A retrospective cohort of adults with ASVCD was formed using healthcare administrative databases in Alberta, Canada (Population 4.4 million). Patients with a new diagnosis between 2008 and 2019 formed the epidemiological cohort (n = 224,600) and those with long-term follow-up (>5 years) formed the outcomes cohort (n = 232,460). The primary outcome of major adverse cardiovascular events (MACE) was assessed and categorized based on the COMPASS trial eligibility. In the outcomes cohort, 77% had only coronary artery disease, 15% had only peripheral artery disease, and 8% had both. Of those, 37% met the COMPASS trial eligibility criteria, 36% met exclusion criteria and 27% did not meet inclusion criteria. Over a median of 7.8 years, the COMPASS exclusion group demonstrated the highest rate of MACE (5.9 per 100 person-years), following by the eligible group and the group that did not meet COMPASS inclusion criteria (3.1 and 1.4 per 100 person-years respectively). The expected net clinical benefit of antithrombotic therapy in the eligible group was 5.6 fewer events per 1000 person-years.

In a real-world population of 4.4 million adults, there are roughly 20,000 new cases of ASVCD diagnosed yearly, with ∼40% being eligible for the addition of low-dose rivaroxaban therapy to antiplatelet therapy. The theoretical implementation of dual antithrombotic treatment in this population could result in a substantial reduction in cardiovascular morbidity and mortality.