Paradoxical emboli following a pulmonary embolus in the presence of a patent foramen ovale

A paradoxical embolism is defined as a systemic arterial embolus due to passage of a venous thrombus through a right to left shunt. We describe a case of acute cerebral vascular accident (CVA), right subclavian arterial embolus, and pulmonary emboli in the setting of a large patent foramen ovale (PFO). A 74-year-old woman with multiple comorbidities presented to the emergency department with acute onset of shortness of breath, weakness, and right arm pain. She was found to have bilateral pulmonary emboli, left CVA, and a right subclavian arterial embolus on computed tomography (CT). She emergently underwent embolectomy of her right upper extremity along with a fasciotomy. On chest CT, a PFO was visualized. Transesophageal echocardiogram (TEE) revealed a large PFO with at least a 3-mm primum/secundum separation and evidence of right to left shunting. Multidisciplinary consensus was that she would benefit from closure of her PFO in order to reduce her risk of further emboli. The patient was agreeable and taken to the catheterization lab where a sizing balloon over a stiff wire was advanced to measure the size of the defect. A 25-mm Cardioform device was successfully delivered across the defect. The patient was started on oral anticoagulation and antiplatelets. In summary, increase in right-sided pressures from pulmonary emboli can cause right to left shunting and lead to a paradoxical embolus. Assessment of patients who present with acute CVA or arterial embolus in the setting of pulmonary emboli with elevated right atrial pressures should include an evaluation for a PFO. Closure of PFO in these patients is of potential additive benefit.