Herein, we report a pediatric case of acute paradoxical cerebral embolism complicated by serious acute pulmonary embolism that was caused by an extremely small patent foramen ovale (PFO). The patient had no medical history suggestive of any other reason. Paradoxical cerebral embolism may occur even with an extremely small PFO because of the increased right-side pressure of the heart and a resulting right-to-left shunt from the acute pulmonary embolism. Although pediatric cases of pulmonary embolism are rare, when diagnosed, clinicians should consider the risk of a concurrent paradoxical cerebral embolism resulting from a latent PFO. The possibility of PFO should be assessed extremely carefully in pediatric critical care by checking for a thrombogenesis tendency and the existence of deep vein thrombosis in the patient.
Keywords: Diameter of PFO; Paradoxical cerebral embolism; Patent foramen ovale (PFO); Pediatric pulmonary embolism; Right-to-left shunt.