BACKGROUND: The ARTESiA trial randomized patients with a pacemaker (PM), implantable cardioverter-defibrillator (ICD), or implantable cardiac monitor (ICM) and with subclinical atrial fibrillation to either apixaban or aspirin.
OBJECTIVE: We aimed to explore the effects of apixaban in the subset of patients with an ICM.
METHODS: We assessed the efficacy outcome of stroke or systemic embolism and the safety outcome of major bleeding, stratifying by device type.
RESULTS: Of 4012 participants, 209 (5.2%) had ICM and 3803 (94.8%) had PM/ICD. Patients with ICM were younger (74.9 ± 7.4 vs 76.9 ± 7.6 years) and more likely to be female (50.2% vs 35.3%) and to have a previous stroke (24.9% vs 7.7%) than those with PM/ICD. In the ICM cohort, stroke/systemic embolism occurred in 1 of 103 in the apixaban group (0.3%/year) vs 9 of 106 in the aspirin group (2.6%/year) (hazard ratio [HR], 0.11; [95% confidence interval {CI}, 0.01-0.88]; absolute risk reduction [ARR] 2.31%/year [95% CI, 0.55-4.07]). The corresponding rates in the PM/ICD cohort were 0.8%/year with apixaban vs 1.2%/year with aspirin (HR, 0.69 [95% CI, 0.49-0.98]; ARR 0.36%/year [95% CI, 0.02-0.70]; Pinteraction = .078 and .002, respectively). Among patients with ICM, major bleeding occurred at 1.3%/year vs 1.1%/year for apixaban vs aspirin (HR, 1.13 [95% CI, 0.30-4.31]). No significant difference in HR or ARR was observed across the device types (Pinteraction = .808 and .406, respectively).
CONCLUSION: In ARTESiA, patients with ICM experienced a stroke rate of 2.6%/year on aspirin, higher than that in the remaining trial population. The risk was significantly reduced by apixaban, consistent with the overall ARTESiA results.