Embolic Stroke Associated with an Intracardiac Thrombus In-Transit in Saddle Pulmonary Embolism

Objectives To describe a case of embolic stroke associated with an intracardiac thrombus in transit identified on computed tomography pulmonary angiography in the setting of saddle pulmonary embolism, highlighting diagnostic challenges when echocardiography is limited. Methods We report the clinical course, imaging findings, and management of a middle-aged male patient who presented with saddle pulmonary embolism and subsequently developed transient focal neurological symptoms. Diagnostic evaluation included brain magnetic resonance imaging, transthoracic echocardiography, and retrospective specialist review of the admission computed tomography pulmonary angiogram. Management decisions were guided by multidisciplinary discussion. Results Brain magnetic resonance imaging demonstrated multiple acute supratentorial infarcts consistent with an embolic etiology. Transthoracic echocardiography was inconclusive due to suboptimal image quality, and transesophageal echocardiography was deferred because interruption of therapeutic anticoagulation was considered high risk. Retrospective review of the computed tomography pulmonary angiogram identified a low-attenuation filling defect within the right atrium extending across the interatrial septum into the left atrium, findings consistent with an intracardiac thrombus in transit. The patient was managed with uninterrupted therapeutic anticoagulation and showed clinical improvement, with complete radiological resolution of the thrombus on follow-up imaging. Conclusions This case demonstrates the diagnostic value of careful evaluation of computed tomography pulmonary angiography beyond the pulmonary vasculature for detecting intracardiac thrombus in transit when echocardiography is limited or contraindicated. Recognition of this entity may influence risk stratification and management strategies in patients with high-burden pulmonary embolism.