Patent Foramen Ovale as a Risk Factor for Neurological Decompression Sickness in Recreational Divers: A Narrative Review
DOI:
https://doi.org/10.12775/JEHS.2026.94.72820Keywords
patent foramen ovale, decompression sickness, neurological DCS, diving medicine, right-to-left shuntAbstract
Background. Decompression sickness (DCS) remains a relevant risk in recreational and professional diving. It results from inert gas (mainly nitrogen) uptake under increased pressure and subsequent bubble formation during ascent. These bubbles may affect tissues and circulation. Neurological DCS is the most severe form and may lead to permanent disability or death.
Patent foramen ovale (PFO), present in approximately 25% of adults, may enable right-to-left shunting and allow venous gas emboli to bypass pulmonary filtration. This mechanism is considered a potential contributor to paradoxical embolization and central nervous system involvement.
Aim. The aim of this review is to evaluate current evidence on the association between PFO and neurological DCS in recreational divers, with emphasis on diagnostic methods and clinical implications.
Materials and methods. A narrative review of English-language publications (2015-2026) was conducted using PubMed and selected peer-reviewed journals in diving and cardiovascular medicine. Original research articles, systematic reviews, meta-analyses, and guidelines were included.
Results. Available evidence suggests that PFO, particularly with large or high-grade right-to-left shunts, is associated with increased risk of neurological DCS. Paradoxical embolization is considered the main underlying mechanism. Diagnostic evaluation is based primarily on contrast echocardiography and transcranial Doppler.
Conclusions. PFO constitutes an important but not exclusive risk factor for neurological DCS. The functional characteristics of the shunt appear to influence this risk. Routine screening is not currently recommended. Targeted evaluation and individualized risk assessment should be considered. Further prospective studies are needed to clarify optimal screening strategies and indications for PFO closure in recreational divers.
References
1. Hampton T, Alsaleem M, Murphy-Lavoie HM. Patent foramen ovale. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025. Available from: https://www.ncbi.nlm.nih.gov/books/NBK493151/https://www.ncbi.nlm.nih.gov/books/NBK493151/
2. Homma S, Messé SR, Rundek T et al. Patent foramen ovale. Nat Rev Dis Primers. 2016;2:15086. https://doi.org/10.1038/nrdp.2015.86
3. Silvestry FE, Cohen MS, Armsby LB et al. Guidelines for the echocardiographic assessment of atrial septal defect and patent foramen ovale: from the American Society of Echocardiography and Society for Cardiac Angiography and Interventions. J Am Soc Echocardiogr. 2015;28(8):910–58. https://doi.org/10.1016/j.echo.2015.05.015
4. Mitchell SJ. Decompression illness: a comprehensive overview. Diving Hyperb Med. 2024;54(Suppl 1):1–53.
https://doi.org/10.28920/dhm54.1.suppl.1-53
5. Mitchell SJ, Bennett MH, Moon RE. Decompression Sickness and Arterial Gas Embolism. N Engl J Med 2022;386(13):1254–64. https://doi.org/10.1056/NEJMra2116554
6. Sander R. Compilation of Henry's law constants (version 5.0.0) for water as solvent. Atmos Chem Phys. 2023;23:10901–12440. https://doi.org/10.5194/acp-23-10901-2023
7. Kelly T, Patrician A, Bryant-Ekstrand M et al. High prevalence of patent foramen ovale in recreational to elite breath hold divers. J Sci Med Sport 2022 ;25(8):652–7. https://doi.org/10.1016/j.jsams.2022.03.014
8. Tobis J, Shenoda M. Percutaneous treatment of patent foramen ovale and atrial septal defects. J Am Coll Cardiol 2012 Oct 30;60(18):1722–32. https://doi.org/10.1016/j.jacc.2012.01.08
9. Germonpré P, Lafère P, Portier W, Germonpré FL, Marroni A, Balestra C. Increased Risk of Decompression Sickness When Diving With a Right-to-Left Shunt: Results of a Prospective Single-Blinded Observational Study (the “Carotid Doppler” study). Front Physiol 2021 29:763408. https://doi.org/10.3389/fphys.2021.763408
10. Honěk J, Šrámek M, Honěk T et al. Screening and Risk Stratification Strategy Reduced Decompression Sickness Occurrence in Divers With Patent Foramen Ovale. JACC Cardiovasc Imaging 2022;15(4):747–56. https://doi.org/10.1016/j.jcmg.2021.06.019
11. Phillips TC, Johnson WR, Rao NL, Murphy CE, Gallagher RM, Waters SN. Active-Duty Sailor Develops PFO-Associated Decompression Sickness: Do Occupational Divers Warrant Alternative Cardiac Screening Standards? J Am Coll Cardiol 2024;84(6):e61–e63. https://doi.org/10.1016/j.jacc.2024.06.010
12. Bhat AR, Arya AK, Bhopale VM et al. Persistent neuroinflammation and functional deficits in a murine model of decompression sickness. J Appl Physiol 2024;137(1):86–98. https://doi.org/10.1152/japplphysiol.00097.2024
13. Tetzlaff K, Eichhorn L. Management of decompression illness. Ger J Sports Med 2025;76(5):182–8. https://doi.org/10.5960/dzsm.2025.634
14. Mize J, Hamm T, Orr S, Song EH, White M, Worth E. Decompression illness and arterial gas embolism. WoundReference. 2025 May 26. Available from: https://woundreference.com/p/topic?id=decompression-sickness
15. Yanagawa Y, Muramatsu K, Nagasawa H, Takeuchi I, Jitsuiki. Type II decompression illness after diving seven meters. Am J Med Case Rep 2022;10:48-50. https://doi.org/10.12691/ajmcr-10-3-2
16. Du L, Liu F, Wu X et al. Unveiling the Value of Contrast Transthoracic Echocardiography Over Enhanced Transcranial Doppler for Right-to-Left Shunt Diagnosis During Synchronous Provocation Testing. J Interv Cardiol 2025;2025:4257495. https://doi.org/10.1155/joic/4257495
17. Miceli G, Trapani S, Cramaro A et al. Right-to-left shunt and transcranial Doppler as a diagnostic tool: when and how to run it. Position statement by the Italian Society of Neurosonology and Cerebral Haemodynamics. Front Neurol 2025;16:1668891. https://doi.org/10.3389/fneur.2025.1668891
18. Apostolos A, Drakopoulou M, Trantalis G et al. The management of patent foramen ovale in divers: where do we stand? Ther Adv Neurol Disord 2022;15:17562864221103459. https://doi.org/10.1177/17562864221103459
19. Šrámek M, Honěk J, Tomek A, Růžičková T, Honěk T, Šefc L. Risk stratification of neurological decompression sickness in divers. Bratisl Med J 2022;123(2):77–82. https://doi.org/10.4149/BLL_2022_022
20. Peppas S, Palaiodimos L, Nagraj S, Kokkinidis DG, Tiwari N, Kharawala A, Mojadidi MK, Mojaddedi S, Ntaios G, Faillace RT, Tobis JM. Right-to-Left Shunt in Divers with Neurological Decompression Sickness: A Systematic Review and Meta-analysis. Healthcare (Basel) 2023;11(10):1407. https://doi.org/10.3390/healthcare11101407
21. Kavinsky CJ, Szerlip M, Goldsweig AM et al. SCAI guidelines for the management of patent foramen ovale. J Soc Cardiovasc Angiogr Interv 2022;1(4):100039. https://doi.org/10.1016/j.jscai.2022.100039
22. Tso JV, Powers JM, Kim JH. Cardiovascular considerations for scuba divers. Heart 2022;108(10):773–80. https://doi.org/10.1136/heartjnl-2021-319601
23. Honěk J, Šefc L, Honěk T, Šrámek M, Horváth M, Veselka J. Patent Foramen Ovale in Recreational and Professional Divers: An Important and Largely Unrecognized Problem. Can J Cardiol 2015;31(8):1061-6. https://doi.org/10.1016/j.cjca.2015.03.010
24. Sommer RJ, Aboulhosn JA. New SCAI guidelines: trying to close the holes in the PFO literature. J Soc Cardiovasc Angiogr Interv 2022;1(4):100337. https://doi.org/10.1016/j.jscai.2022.100337
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2026 Sylwia Pietrajtis, Angelika Juszczyk, Dominika Brożyna, Mateusz Wnęk, Bartłomiej Sałapski, Mateusz Kubicki, Wojciech Kukiełka, Michał Łebek, Wiktoria Komornik, Jakub Gałwiaczek
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
The periodical offers access to content in the Open Access system under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0
Stats
Number of views and downloads: 77
Number of citations: 0
