ABSTRACT NUMBER: ESOC2026A138 EARLY VERSUS DELAYED INSERTABLE CARDIAC MONITOR IMPLANTATION AFTER ESUS STROKE AND THE YIELD OF ATRIAL FIBRILLATION DETECTION: A SYSTEMATIC REVIEW AND META-ANALYSIS

Abstract Background and aims The clinical utility of implantable cardiac monitors (ICMs) for atrial fibrillation (AF) detection following cryptogenic stroke or embolic stroke of undetermined source (ESUS) is well established. However, the optimal timing for ICM implantation to maximize diagnostic yield remains uncertain. We aim to systematically review the literature and conduct a meta-analysis to determine whether earlier ICM implantation after cryptogenic stroke or ESUS ischemic stroke improves detection rates and reduces the time to AF diagnosis. Methods A comprehensive search of PubMed, Embase, and Cochrane CENTRAL was conducted from inception to June 2025. We included observational studies or randomized trials reporting ICM in patients with ESUS or cryptogenic stroke/TIA, providing data on AF detection rates and/or timing metrics (stroke-to-ICM interval, ICM-to-AF interval). The primary outcomes were pooled AF detection rate and mean time from ICM implantation to AF diagnosis. Timing of implantation was assessed as a continuous and categorical (early, intermediate, delayed) variable. Results Forty-seven studies (N = 6,918 patients) were included. Early ICM implantation (<31.5 days from index event) was associated with a higher AF detection rate compared to delayed implantation (30.0% vs. 23.7%; p = 0.0017), independent of monitoring duration (Figure 1). For each additional day of delay in ICM implantation, the time to AF diagnosis increased by an additional 0.32 days on average, even after accounting for monitoring duration (p = 0.0007). Conclusions These findings suggest that earlier ICM implantation enhances AF detection after ESUS or cryptogenic stroke and shortens diagnostic delay. Conflict of interest Nothing to disclose Figure 1 - belongs to Results