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Updated: Jun 13, 2026
10:52
Closure of a Patent Foramen Ovale (PFO): An Intervention Sequence
Published on: December 23, 2022
[Patent foramen ovale and decompression illness in divers]
Wiebke Sivertsen1, Jan Risberg, Gunnar Norgård
1Seksjon for pediatri, Institutt for klinisk medisin, Universitetet i Bergen, Norway.
Summary
Patent foramen ovale (PFO) is common, but the absolute risk of decompression illness in divers with PFO is low. Screening for PFO in divers is not recommended due to the small absolute risk.
Area of Science:
- Cardiovascular physiology
- Diving medicine
- Medical diagnostics
Context:
- Patent foramen ovale (PFO) affects approximately 25% of the population.
- PFO has been implicated as a potential cause of decompression illness (DCI) in divers.
- The necessity of screening and treating PFO in divers remains unclear.
Purpose:
- To investigate the relationship between PFO and DCI risk in divers.
- To identify specific diver categories that may benefit from PFO screening.
- To provide guidance for divers diagnosed with PFO.
Summary:
- Divers with PFO have a fivefold higher risk of DCI compared to those without, but the absolute risk remains low (2.5 per 10,000 dives).
- A causal link between PFO and DCI has not been established.
- While PFO closure is low-risk, its efficacy in divers is not documented.
Impact:
- Current evidence does not support routine PFO screening for all divers.
- Transcatheter closure of PFO is generally reserved for occupational divers experiencing DCI.
- Further research is needed to clarify the role of PFO in DCI and guide clinical recommendations for divers.
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