Management of paradoxical embolism in a patient with coexisting patent foramen ovale and masked pulmonary arteriovenous fistula A case report

Rationale: Paradoxical embolism (PE) is an important cause of cryptogenic stroke, particularly in young patients, which usually have a relation with an unexpected route in circulation. Here we report a rare case of cryptogenic stroke carried 2 uncommon malformations. Patient concerns: A 48-year-old female experienced double neurological events in just 2 months. Diagnosis: Patent foramen ovale was diagnosed with transesophageal echocardiography and successfully occluded in the first admission due to stroke. In the second admission, chest tomographic angiography found a chordae shadow in the right middle lobe, was the first clue for pulmonary arteriovenous fistula (PAVF), thereafter further confirmed by the enhanced pulmonary computed tomographic angiography. Interventions: This patient then received intervention occlusion therapy with coils for PAVF under the help of microcatheter. Given the possible native origin of the thrombus in PAVF due to the spiral morphology, dual antiplatelet therapy was prescribed for this patient for the first 3 months to prevent device-related embolism after discharge, and the following single antiplatelet therapy was mandated. Outcomes: No recanalization was detected on the follow-up enhanced pulmonary computed tomographic angiography (PCTA), no neurological defect event recurred in the 16 months of follow-up. Lessons: Computed tomograph (CT) deserved more value in screening and depicting the morphology of the PAVF, particular in young adults with no apparent arteriosclerotic risk factor. Microcatheter would be helpful for intervention treatment. Antiplatelet therapy might be adequate in specific patients, yet definitely need more evidence to verify.