Fatal Mesenteric Ischemia From a Presumed Paradoxical Embolism Through a Patent Foramen Ovale

Acute mesenteric ischemia is a highly lethal vascular emergency most often caused by arterial embolism. Paradoxical embolism through a patent foramen ovale (PFO) is a well-recognized cause of cryptogenic stroke, but it is a rare and underrecognized cause of mesenteric arterial occlusion. A 68-year-old woman with a history of paradoxical embolism, chronic deep vein thrombosis, and a patent foramen ovale presented with sudden, severe abdominal pain and vomiting. She had previously undergone brachial artery embolectomy and had been maintained on long-term apixaban, which she later discontinued after being lost to follow-up. Computed tomography angiography revealed abrupt occlusion of the superior mesenteric artery and a newly identified left renal mass suspicious for malignancy. Telemetry showed no atrial fibrillation, blood cultures were negative, and no intracardiac thrombus was identified. Lower extremity Doppler ultrasound demonstrated chronic but not acute deep vein thrombosis. In the absence of alternative arterial embolic sources and given the temporal relationship to anticoagulation interruption, presumed paradoxical embolism was considered the most plausible mechanism. Despite emergent surgery, the patient developed extensive bowel necrosis and died after transition to comfort-focused care. This case adds to the limited literature on extracerebral paradoxical embolism and highlights the importance of sustained anticoagulation and longitudinal follow-up in patients with PFO and venous thromboembolism, particularly when additional hypercoagulable conditions are suspected.