While there is a high prevalence of patent foramen ovale in adults, paradoxical embolism via a patent foramen ovale is rare. Previous echocardiographic studies indicated that paradoxical embolism might only occur in patients with high-risk features of patent foramen ovale (i.e., large defect size, presence of a Eustachian valve, and high right atrial pressure). Here, we present a case of patent foramen ovale with high-risk CT features for paradoxical embolism.