At the 43rd Annual Scientific Meeting of South Pacific Underwater Medical Society going on May 18 – 25, 2014, a key theme is PFO and diving. The keynote speaker is Dr. Peter Wilmshurst, the cardiologist and diving physician who first described the association between PFO and decompression sickness in 1986. Here, he presented his findings in several hundred cases of DCS. His insight into this problem is most valuable and we are looking forward to the publication of a synthesis of his findings.
Others presented personal experience of PFO closure, diving with persistent PFO, cases of postdive vertigo associated with PFO, and more. At the end, there will be a discussion with the goal of producing the SPUMS position paper about PFO and diving.
We presented on DAN’s ongoing prospective study that aims to establish who is better off: divers with PFO who continue diving conservatively or divers who undergo closure of their PFO before returning to diving. As the association of PFO and DCS seem unquestionable (this is not to imply that the causation is straightforward), the relationship between the two remains probabilistic; not all divers with PFO get DCS. Indeed, about 5% of all divers are likely to experience some symptoms of DCS in their lifetime and not all of them have PFO. About 15% of divers have a significantly large PFO, but not all of them get DCS.
Thus, for divers who are eventually diagnosed with PFO and want to continue diving, the question remains which risk is greater—the possibility of a DCS hit or the risk of side effects associated with the closure. If it is found that the two risks are comparable, the question to ask concerned divers: What is more acceptable a) the known risk of DCS, which can be mitigated with conservative practices or retirement from the sport or b) the risk of adverse events associated with an implant in your heart for the rest of your life?
Post written by: Petar Denoble, MD, D.Sc.