A rare case of paradoxical embolization due to an acquired extracardiac right-to-left shunt during covid-19 infection: Every street leads to heart

Right-to-left shunt may be a cause of paradoxical embolization (and cryptogenic cerebral ischemic events). Patent foramen ovale and pulmonary arterio-venous malformations are the most common cause of paradoxical embolization; however, some rare cardiovascular lesions may cause a right-to-left shunt with consequent paradoxical embolization. We describe a case of a young child with superior sinus venosus atrial septal defect who underwent surgical closure and developed a cryptogenic cerebral ischemic attack due to a rare cause of paradoxical embolization, during a long-term follow-up. Learning objective: This case report cautions us to consider some rare causes of parodixal embolization such as systemic-pulmonary venous connections. The diagnosis should be always suspected in patients with paradoxical embolization without a patent foramen ovale and/or arterio-venous pulmonary malformations.