Eustachian Valve-Enhanced Paradoxical Cerebral Embolism: A Case Report

Area of Science:

• Neurology
• Cardiology
• Hematology

Background:

• Cryptogenic stroke often has elusive embolic origins not meeting TOAST criteria.
• Atrial fibrillation (AF) is a common occult cause, often detected by implantable loop recorders (ILR).
• Paradoxical embolism through a patent foramen ovale (PFO) is a less common but significant cause of stroke.

Observation:

• A 75-year-old male with cryptogenic stroke history presented with aphasia and hemiparesis.
• Mechanical thrombectomy successfully recanalized the occluded middle cerebral artery.
• Implantable loop recorder monitoring excluded atrial fibrillation.

Findings:

• Transesophageal echocardiography revealed a large Eustachian valve and patent foramen ovale (PFO).
• High WT1mRNA levels indicated acute monocytic leukemia (AMoL) was not in molecular remission, suggesting a hypercoagulable state.
• Deep vein thrombosis was not evident, but the combination of PFO, Eustachian valve, and hypercoagulability pointed to paradoxical embolism.

Implications:

• This case underscores that paradoxical cerebral embolism should be considered in cryptogenic stroke, especially with a large Eustachian valve and PFO.
• Even without overt deep vein thrombosis, a hypercoagulable state in the context of these cardiac findings warrants investigation.
• Diagnostic exclusion of AF and other common stroke etiologies supports the diagnosis of paradoxical embolism.