This narrative review synthesizes evidence from the ARTESiA and NOAH-AFNET 6 trials regarding anticoagulation for device-detected atrial high-rate episodes and subclinical atrial fibrillation. While DOACs significantly reduce ischemic stroke risk, they increase major bleeding; the annual untreated stroke rate remains low at approximately 1%. Clinical decisions should therefore prioritize absolute thromboembolic risk, bleeding susceptibility, and patient preferences over rigid episode-duration thresholds. The authors propose a staged net-clinical-benefit framework to help cardiologists and primary care physicians individualize management, balancing stroke prevention against bleeding harm in this growing patient population.
Device-detected atrial high-rate episodes and subclinical atrial fibrillation occupy an intermediate state between an electronic signal and clinically documented atrial fibrillation. ARTESiA showed that apixaban reduced stroke or systemic embolism compared with aspirin while increasing major bleeding. NOAH-AFNET 6 found no significant reduction in its broader composite of cardiovascular death, stroke, or systemic embolism with edoxaban and more death or major bleeding. Together, the trials indicate a low untreated stroke rate near 1% per year, reduced ischemic stroke with direct oral anticoagulation, and increased major bleeding. Treatment depends on absolute risk, outcome severity, and competing harm rather than a binary reading of statistical significance. This narrative review distinguishes randomized evidence, formal guideline recommendations, the 2026 American College of Cardiology Scientific Statement, and the authors' proposed framework, integrating diagnostic certainty, device source, episode characteristics and trajectory, prior stroke or transient ischemic attack, vascular and atrial substrate, bleeding susceptibility, and patient priorities. After rhythm confirmation, higher thromboembolic risk-including subgroup evidence after prior stroke or transient ischemic attack-may favor consideration of anticoagulation when bleeding risk is acceptable; uncertain signals, isolated short episodes, lower clinical risk, or substantial competing harm may favor continued surveillance. The six-minute trial eligibility criterion, episode duration, and device type are not independently validated universal treatment triggers, and no universally validated burden threshold exists. The proposed staged net-clinical-benefit framework is conceptual and hypothesis-generating, has not been prospectively or externally validated, and is not intended as a universal prescriptive treatment algorithm.
