BACKGROUND: Atrial fibrillation is a primary cause of ischemic stroke, necessitating early detection, particularly in patients with embolic stroke of undetermined source. While nurseled continuous electrocardiogram monitoring allows real-time rhythm assessment in acute stroke units, its specific clinical impact remains insufficiently clarified. AIM: To evaluate the impact of nurse-led notification of suspected atrial fibrillation in patients with cryptogenic stroke. STUDY DESIGN: A retrospective medical record review was conducted on patients with cryptogenic stroke admitted to a stroke unit between January and December 2022 in a tertiary general hospital in South Korea. Clinical characteristics and outcomes were compared based on the presence of nurse-led atrial fibrillation notifications. RESULTS: In total, 235 patients were included. Nurse-led notifications for suspected atrial fibrillation occurred in 24 (10.2%) patients of whom 95.8% were confirmed to have overt atrial fibrillation. The nurse-led notification group experienced a shorter time to anticoagulation initiation (3.7 vs. 5.6 days; p = 0.015), shorter hospital stay (7.2 vs. 12.9 days; p = 0.015) and lower overall medical costs ($5889.6 vs. $8487.6; p = 0.021) among the group of newly confirmed atrial fibrillation. Nurses with ≥ 10 years of neurology experience were associated with atrial fibrillation detection (RR = 17.70, 95% confidence interval = 4.64-67.70, p < 0.001). Nurse-led notification was independently associated with reduced hospital stay (B = -5.08, 95% confidence interval = -8.33 - -1.83, p = 0.002). CONCLUSIONS: Nurse-led notification of suspected atrial fibrillation was associated with shorter hospital stays and a potential benefit in the early initiation of anticoagulation. Integrating experienced nurses into structured cardiac monitoring protocols may improve the efficacy of care for patients with embolic stroke of undetermined source. RELEVANCE TO CLINICAL PRACTICE: Nurse-led atrial fibrillation detection significantly improves clinical and economic outcomes. These findings underscore the critical role of clinical expertise in cardiac monitoring, suggesting that such initiatives can optimise resource allocation and improve clinical outcomes in stroke units.