Large free-floating right atrial mass presenting as intermediate-high risk pulmonary embolism: is reperfusion a better definite strategy?

We present a woman in her 60s diagnosed with an intermediate-high risk acute pulmonary embolism and a large, non-serpiginous right atrial (RA) mass. Conservative therapy with unfractionated heparin was started and further assessment of the mass with cardiac MRI suggested thrombus as the most likely diagnosis. Despite 1 month of anticoagulation, mass size remained stable and surgical RA embolectomy and left pulmonary endarterectomy was performed. Histopathology confirmed thrombus. The patient died 10 weeks after surgery.