Abstract
IMAGES: Cor triatriatum sinister/echocardiogram and cardiac computed tomography. CASE SUMMARY: The patient was a 21-year-old woman with an embolic stroke who was found to have an unobstructed Cor triatriatum sinister (CTS) and patent foramen ovale and underwent a patent foramen ovale device closure and subsequent anticoagulation therapy. Case reports of CTS associated with stroke have been previously published, and CTS is recognized as a risk factor for an embolic stroke; however, the mechanism of embolic stroke is unclear. TAKE-HOME MESSAGE: Further study is warranted to understand the mechanism and role of CTS for embolic stroke and optimal therapeutic options to reduce the risk of recurrent stroke.