The presence of a patent foramen ovale in scuba divers was associated with a significantly higher risk of experiencing ≥1 major decompression illness events compared to those without (29% vs 6%, P=0.016).
Observational (n=230)
Does the presence and size of a patent foramen ovale increase the risk of decompression illness in scuba divers?
The presence and increasing size of a patent foramen ovale in scuba divers is associated with a significantly higher risk of major decompression illness, although the absolute risk remains low.
Odds Ratio: 5
Absolute Event Rate: 29% vs 6%
p-value: p=0.016
BACKGROUND: The risk of developing decompression illness (DCI) in divers with a patent foramen ovale (PFO) has not been directly determined so far; neither has it been assessed in relation to the PFO's size. METHODS: In 230 scuba divers (age 39+/-8 years), contrast trans-oesophageal echocardiography (TEE) was performed for the detection and size grading (0-3) of PFO. Prior to TEE, the study individuals answered a detailed questionnaire about their health status and about their diving habits and accidents. For inclusion into the study, > or =200 dives and strict adherence to decompression tables were required. RESULTS: Sixty-three divers (27%) had a PFO. Overall, the absolute risk of suffering a DCI event was 2.5 per 10(4) dives. There were 18 divers (29%) with, and 10 divers (6%) without, PFO who had experienced > or =1 major DCI events P=0.016. In the group with PFO, the incidence per 10(4) dives of a major DCI, a DCI lasting longer than 24 h and of being treated in a decompression chamber amounted to 5.1 (median 0, interquartile range IQR 0-10.0), 1.9 (median 0, IQR 0-4.0) and 3.6 (median 0, IQR 0-9.8), respectively and was 4.8-12.9-fold higher than in the group without PFO (P<0.001). The risk of suffering a major DCI, of a DCI lasting longer than 24 h and of being treated by recompression increased with rising PFO size. CONCLUSION: The presence of a PFO is related to a low absolute risk of suffering five major DCI events per 10(4) dives, the odds of which is five times as high as in divers without PFO. The risk of suffering a major DCI parallels PFO size.
S Torti (2004) conducted an observational in Decompression illness (n=230). Patent foramen ovale (PFO) vs. No PFO was evaluated on ≥1 major decompression illness (DCI) events (OR 5, p=0.016). The presence of a patent foramen ovale in scuba divers was associated with a significantly higher risk of experiencing ≥1 major decompression illness events compared to those without (29% vs 6%, P=0.016).