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Closure of a Patent Foramen Ovale (PFO): An Intervention Sequence
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Closure of a Patent Foramen Ovale (PFO): An Intervention Sequence

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Is stroke a paradoxical embolism in patients with patent foramen ovale?

Masahiro Yasaka1, Ryoichi Otsubo, Hiroshi Oe

  • 1Cerebrovascular Division, Department of Medicine, National Cardiovascular Center, Osaka, Japan.

Internal Medicine (Tokyo, Japan)
|June 9, 2005
PubMed

Insights

In stroke patients with patent foramen ovale (PFO), paradoxical embolism is not the sole cause of stroke. Other stroke mechanisms frequently contribute, even in the presence of PFO.

Area of Science:

  • Cardiology
  • Neurology
  • Vascular Medicine

Background:

  • Patent foramen ovale (PFO) is a potential cause of stroke, particularly paradoxical embolism.
  • Distinguishing stroke mechanisms in PFO patients is crucial for effective treatment.

Purpose of the Study:

  • To investigate and compare stroke mechanisms in patients with PFO and sinus rhythm versus those with PFO and atrial fibrillation, and those with atrial fibrillation alone.
  • To assess the prevalence of paradoxical embolism in stroke patients with PFO.

Main Methods:

  • Retrospective review of medical records for 111 PFO with sinus rhythm (PFO-S) patients, 25 PFO with atrial fibrillation (AF) patients (PFO-AF), and 67 AF patients without PFO.
  • Clinical and neuroradiological findings were compared.
  • Deep vein thrombosis (DVT) was investigated to assess for paradoxical embolism criteria.

Main Results:

  • PFO-S patients showed more hypercholesterolemia and posterior circulation lesions compared to PFO-AF and AF groups.
  • Other embolic sources were identified in 52.9% of PFO-S and PFO-AF patients.
  • Definite paradoxical embolism was rare (3.2%), while probable paradoxical embolism was found in 35.5% of PFO patients with DVT screening.

Conclusions:

  • Stroke in PFO patients can result from mechanisms beyond paradoxical embolism.
  • Identifying alternative stroke etiologies is essential for comprehensive stroke management in PFO patients.
Abstract

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