Screening and Risk Stratification Strategy Reduced Decompression Sickness Occurrence in Divers With Patent Foramen Ovale
Abstract
OBJECTIVES: This paper sought to evaluate the occurrence of decompression sickness (DCS) after the application of a patent foramen ovale (PFO) screening and risk stratification strategy. BACKGROUND: PFO is associated with an increased risk of DCS.
Recently, transcatheter closure was reported to reduce DCS occurrence in divers with a high-grade shunt. However, to date, there are no data regarding the effectiveness of any PFO screening and risk stratification strategy for divers.
METHODS: A total of 829 consecutive divers (35.4 +- 10.0 years, 81.5% men) were screened for PFO by means of transcranial color-coded sonography in the DIVE-PFO (Decompression Illness Prevention in Divers with a Patent Foramen Ovale) registry. Divers with a high-grade PFO were offered either catheter-based PFO closure (the closure group) or advised conservative diving (high grades).
Divers with a low-grade shunt were advised conservative diving (low grades), whereas those with no PFO continued unrestricted diving (controls). A telephone follow-up was performed.
To study the effect of the screening and risk stratification strategy, DCS occurrence before enrollment and during the follow-up was compared. RESULTS: Follow-up was available for 748 (90%) divers.
Seven hundred and 2 divers continued diving and were included in the analysis (mean follow-up 6.5 +- 3.5 years). The DCS incidence decreased significantly in all groups, except the controls.
During follow-up, there were no DCS events in the closure group; DCS incidence was similar to the controls in the low-grade group (HR: 3.965; 95% CI: 0.558-28.18; P = 0.169) but remained higher in the high-grade group (HR: 26.170; 95% CI: 5.797-118.16; P < 0.0001). CONCLUSIONS: The screening and risk stratification strategy using transcranial color-coded sonography was associated with a decrease in DCS occurrence in divers with PFO.
Catheter-based PFO closure was associated with a DCS occurrence similar to the controls; the conservative strategy had a similar effect in the low-grade group, but in the high-grade group the DCS incidence remained higher than in all other groups.