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Closure of a Patent Foramen Ovale PFO: An Intervention Sequence
Published on: December 23, 2022
Paradoxical brain embolism in a young man: is it only a patent foramen ovale?
Lidia Wozniak1, Maksymilian Mielczarek2, Robert Sabiniewicz1
1Department of Pediatric Cardiology and Congenital Heart Diseases, Medical University, Gdansk, Poland.
Abstract:
Paradoxical embolism is considered the major cause of cerebral ischemic events in young patients. The most common cause of paradoxical embolism, which has been widely described, is right-to-left shunting (RLS) at cardiac level through a patent foramen ovale (PFO). Rarely paradoxical embolism can also be caused by RLS at pulmonary level due to pulmonary arteriovenous fistula (PAVF). Herein, we present a case of a young man, who experienced transient ischemic attack (TIA) due to paradoxical embolism, in whom both abovementioned abnormalities coexisted. This coincidence is very rare (noted in only 1% of patients with cryptogenic stroke or TIA), but it highlights the importance of searching for extracardiac RLS in patients with cryptogenic stroke, even if a PFO has been detected.
Insights
Paradoxical embolism causing stroke in young adults often stems from a patent foramen ovale (PFO). This case highlights the rare coexistence of cardiac and pulmonary right-to-left shunts (RLS) causing TIA.
Area of Science:
- Neurology
- Cardiology
- Vascular Medicine
Background:
- Paradoxical embolism is a significant cause of ischemic stroke in young individuals.
- Right-to-left shunting (RLS) through a patent foramen ovale (PFO) is the most common etiology.
- Pulmonary arteriovenous fistulas (PAVF) are a rare cause of RLS and paradoxical embolism.
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