Long-term cardiac rhythm monitoring has become a central component of the diagnostic evaluation of patients with ischemic stroke in whom atrial fibrillation (AF) is suspected but not initially detected. Implantable loop recorders (ILRs) substantially increase AF detection compared with conventional short-term monitoring, particularly when surveillance is extended over months to years. However, increased detection has not consistently translated into fewer strokes, underscoring important limitations in current paradigms. Growing evidence supports atrial cardiopathy as the underlying substrate predisposing to thromboembolism, with AF representing a variable electrical manifestation rather than the primary disease itself. Electrocardiographic and echocardiographic markers of atrial cardiopathy, including abnormal P-wave indices, left atrial enlargement, and impaired atrial function, help identify patients most likely to benefit from prolonged monitoring. This review examines the role of ILRs in post-stroke patients through the lens of atrial cardiopathy, emphasizing biologic plausibility, patient selection, and disciplined interpretation of monitoring results to optimize clinical relevance and avoid uncritical escalation of therapy.