More on PFO
The PFO story goes on. There have been studies to determine if a PFO increases risk of stroke (the clinical trials are negative to date), migraine headaches (again the clinical trials are negative) and decompression sickness (DCS). In the case of DCS, there is not likely to be a large prospective clinical trial because the number of people at risk is small and clinical trials are expensive so the cost benefit relation is not favorable.
The observations on divers with DCS and a PFO suggest that large PFOs impart some risk, while small PFOs don't. Regardless, there is no risk if there are no or very few bubbles. For most sport divers following their computer for no-D diving, there is minimal risk of bubbles forming in the veins and the PFO won't make much difference. If you are a technical diver doing deep dives or mixed gas dives, a large PFO might produce some risk. Closing a PFO has its own risk, with the complication rate stated to be around 2-5%, while the risk of a DCS event is much lower - about 0.02 - 0.05%.
Based on these numbers, I would not recommend getting a PFO closed to improve risk for DCS, and certainly would not consider a PFO as a prohibition for diving. You can find more details about a PFO at: http://www.scubamed.com/PFO_page.html
The observations on divers with DCS and a PFO suggest that large PFOs impart some risk, while small PFOs don't. Regardless, there is no risk if there are no or very few bubbles. For most sport divers following their computer for no-D diving, there is minimal risk of bubbles forming in the veins and the PFO won't make much difference. If you are a technical diver doing deep dives or mixed gas dives, a large PFO might produce some risk. Closing a PFO has its own risk, with the complication rate stated to be around 2-5%, while the risk of a DCS event is much lower - about 0.02 - 0.05%.
Based on these numbers, I would not recommend getting a PFO closed to improve risk for DCS, and certainly would not consider a PFO as a prohibition for diving. You can find more details about a PFO at: http://www.scubamed.com/PFO_page.html
posted by Fred Bove, MD, PhD at 2:32 PM
1 Comments:
Thank you very much for posting this blog on a not-so-clear topic. An elderly friend of mine had to rescue his wife when she passed out at 65 feet of depth due to a PFO. Fortunately, she recovered and did go ahead to have the PFO fixed and returned to diving without incident. Is there a particular size factor involved? Would you recommend correction if the PFO is larger than most?
I realize data are not available, but I would greatly appreciate your opinion. Don Jacobson, MD
Disabled psychiatrist and sleep medicine specialist and former diver - www.scubagearpro.com/blog
Thanks for your input.
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