Thrombus-In-Transit Across Patent Foramen Ovale Causing Dynamic Embolism to the Left Main Coronary and Pulmonary Arteries.

BACKGROUND

Paradoxical embolism via a patent foramen ovale (PFO) is a rare cause of acute myocardial infarction; its simultaneous or sequential occurrence with pulmonary embolism is even rarer.

CASE SUMMARY: A 60-year-old woman with no prior cardiac history presented with anterior ST-segment elevation myocardial infarction and cardiogenic shock. Preprocedural transthoracic echocardiography showed a large mobile thrombus straddling the interatrial septum through a PFO. Coronary angiography revealed complete left main coronary artery occlusion; thrombus aspiration restored TIMI flow grade 3. Minutes after reperfusion, the patient developed refractory shock and severe hypoxemia. Repeat echocardiography demonstrated disappearance of the intracardiac thrombus and new right ventricular dysfunction; pulmonary angiography confirmed large right pulmonary artery thrombus. Despite systemic thrombolysis and intra-aortic balloon pump support, the patient could not be resuscitated.

DISCUSSION: This case provides direct serial imaging of thrombus-in-transit dynamics, documenting rapid embolization from the PFO into both coronary and pulmonary circulations within minutes.

TAKE-HOME MESSAGES: Thrombus-in-transit across a PFO can produce sequential life-threatening embolization to both systemic and pulmonary circulations. Apparent disappearance of an intracardiac thrombus on repeat imaging in an unstable patient should prompt immediate evaluation for pulmonary embolism.