Left Atrial Mass After Patent Foramen Ovale Closure.

IMAGE(S): Transesophageal echocardiography, cardiac computed tomography, and histopathology. CASE SUMMARY: A 50-year-old man with previous cryptogenic stroke and patent foramen ovale closure was found to have a large mobile mass on the left atrial side of the occluder approximately 33 months after implantation. Surgical extraction was performed because of embolic risk. Pathology demonstrated benign myocardium mixed with adipose tissue, supporting atypical endothelialization rather than thrombus or infection. TAKE-HOME MESSAGES: Late masses on patent foramen ovale occluder devices may mimic thrombus or vegetation. Multimodality imaging, surgical inspection, and pathology are essential for diagnosis.