Right Atrial Thrombus in Transit: A Case of Spontaneous Embolisation Captured Across Echocardiography

ABSTRACT Right atrial (RA) thrombi are rare but life‐threatening findings, often representing ‘clot in transit’ with a high risk of embolisation and mortality. Their identification often signals an impending pulmonary embolic event and calls for rapid, thoughtful decision‐making. We report the case of a 65‐year‐old man with atrial fibrillation on rivaroxaban who presented with acute ischaemic stroke and was subsequently found to have a large RA thrombus. Shortly thereafter, he developed hypoxia, and computed tomography (CT) pulmonary angiography revealed bilateral pulmonary emboli. Interventional angiography was performed for planned thrombectomy, but the clot was no longer visualised, confirming spontaneous embolisation. Repeat echocardiography demonstrated complete resolution of the thrombus. This case highlights the natural history of RA thrombus in transit, the pivotal role of multimodality imaging and the challenges of management in patients with concurrent contraindications to thrombolysis.