Background: Patients who had a cryptogenic stroke (CS) suspected to be causally related to a patent foramen ovale (PFO) are candidates for percutaneous PFO closure. In such patients it is important to screen for atrial fibrillation (AF). Limited guidance is available regarding AF monitoring strategies in CS patients with PFO addressing optimal monitoring technology and duration. Aim: To provide a narrative review of cardiac rhythm monitoring in CS patients considered for PFO closure, including current practices, stroke recurrences after CS, findings from monitoring studies in CS patients, and predictors for AF detection published in the literature. To propose an personalized strategy for cardiac monitoring in CS patients, accounting for aspects predicting AF detection. Summary of review: AF detection in CS patients is predicted by age, left atrial enlargement, prolonged PR interval, frequent premature atrial contractions, interatrial conduction block, diabetes, prior brain infarctions, leukoaraiosis, elevated BNP/NT-proBNP levels, and a family history of AF, as well as composed scores (e.g., CHA2DS2-VASc, AF-ESUS). The causal role of the PFO may be accounted for by the RoPE score and/or the PASCAL classification. Conclusions: A personalized approach to AF detection in CS patients is proposed, accounting for the likelihood of AF detection and aimed at obtaining sufficient confidence regarding the absence of AF in patients considered for PFO closure. Additionally, the impact of high risk PFO features on the monitoring strategy is discussed