Patent Foramen Ovale

gtzavelas

this is a very shocking statement. I guess that there is no real study about DCI after PFO closure as there sample should be very small??? any info would be extremely interesting
i hope you will have a full and fast recovery...

pchanning

Hi Phil, I'll see you again this year if you are there (obviously at the bar - I dont suppose Rebreather divers need to buy kit anymore!). Good luck with the tests mate.

Andre, really sorry to hear that. Interestingly, My PFO Report states that I am at increased chance of getting bent again, having had this happen. I need to find out more about this. However, I got my PFO fixed to reduce the chances of a severe stroke in later life. We'll have to see.

Any Doc's care to comment??

__________________
Cheers
Paul

The key to enlightenment... is survival.

Mdemon

That's an extremely interesting post. DAN was muttering similar. Any more info?

saturation

Summaries:

Primary Care Diving Medicine: March 2007

Detailed papers on PFOs are in an excellent post by bendomatic on this thread.

http://www.rebreatherworld.com/dive-...html#post69095

__________________
Safe Diving and Best Wishes,

I.G. Saturation, MD

{ Comments are informational only and not meant to be medical advice applicable to a particular case. Consult your physician when considering information posted here }

MattW

Good to hear that your PFO was successfully fixed.

However this has got me thinking.....
I've never had more than sub-clinical dcs, but I guess given the statistics, there's always the chance that I might actually have a pfo lurking in the background ready to bite me.

So if I was to pay for a pfo test and if one was subsequently discovered would it be fixable on the nhs, or would I have to pay for a private operation (I've heard some frightening costs bandied about)?

Any comments gratefully received

cheers
Matt

Doppler

Matt:

unsure what sort of dives you are pulling and where your personal comfort level sits with regards playing guinea pig with deco theory, but reading through the literature -- have a butcher's at the stuff Marv (saturation) has on his site -- it would seem to me to be somewhat extreme to be tested without due cause.

That said, someone like Marv would be the best person to ask... take care

apitkin

There are obviously no randomised controlled clinical trials, the gold standard of evidence in medicine. So what we are left with is some theory and some less good evidence.

The theory that links DCI risk to the presence of a PFO is based on the simple idea that venous gas bubbles pass through the PFO to the arterial circulation, where they cause clinical symptoms by being carried to the affected organs, principally the central nervous system. So it makes sense that closing the PFO with a device should reduce the risk of DCI.

However, it is clear that the disease entities grouped together as DCI are not all caused by embolisation (travel in the bloodstream) of gas bubbles. It does not explain why, for example, the spinal cord is often so badly affected in severe DCI as this is way out of proportion to its blood supply. (It is probable that gas bubbles form in situ in the spinal cord due to its content of lipid-rich myelin.)

So it may be that closure of a PFO only reduces the likelihood of certain types of DCI.

But there's more. In animal experiments it has been observed that gas bubbles form on any foreign material within the heart (such as central venous catheters) when those animals are subjected to severe decompression stress. It could be that a closure device acts as a focus for bubble formation within the heart, thereby actually increasing the risk of DCI.

Now, I have no evidence that this actually happens, but I am pointing it out as a possible example of the law of unintended consequences which acts so often in medicine.

Many eminent diving doctors are not convinced of the usefulness in terms of overall balance of benefit and risk of having a PFO (as opposed to a significant ASD) closed, and I share their scepticism. You will, I dare say, hear a different point of view from the cardiologists, but most of them know very little about the pathophysiology of diving disease.

Andy

dteubner

A PFO is present in 30% of the non diving population, therefore presumably present in 30% of the diving population.

The presence of a PFO increases the odds of having serious neurological DCI about 4 fold.

This means that, if you get serious neurological DCI AND you have a PFO then there is about a 75% chance that the PFO contributed to the DCI. YOU CAN NOT SAY THAT THE PFO CAUSED THE BEND, just that it was likely to have.

PFOs do not increase the risk of musculoskeletal, pain only type bends, so if these are the 'minor hits' then they had nothing to do with a PFO.

Size is likely to be important, and small holes that do not shunt blood easily are probably of very little significance.

To look at it another way, in a population of divers about 50% of underserved serious neurological DCI can be ascribed to a PFO, which menas that 50% CAN'T and you can't establish causality in an individual diver. You can, on the other hand ascribe causality to PFO for minor, pain only DCI. It didn't cause it.

There is a line in The Origin of Species where Darwin says that the appearence of particular species is due to "what we may call chance". He means that it's not really due to chance, but there mechanisms involved are so complex that we can never really understand them. Very little in medicine (or indeed life) can be understood in great enough detail to really say this caused that, causality is extremely difficult to establish. Because of this, we use statistics to try to make sense of things. People don't like this approach.

Here are some more things - if every diver who had a PFO had it closed and IF having it closed removed all of the increased risk of DCI then the incidence of serious neurological DCI woul fall by 50%. IT WOULD NOT GO AWAY, it would just halve.

PS - Apologies for the deja-vu.

__________________
Dave T

Hanlon's Razor - Never attribute to malice that which can be adequately explained by stupidity.

ms.navigante

I would like to address my case hoping that someone can give me any suggestion and quoting what Andy said that I perfectly agree.
After several cutaneous DCS that were getting worse and worse also with NDL dives and after a really bad one, I decided to check my heart and they found a 3rd grade PFO of a 15mm diameter. During the first check with the transcranical color doppler echography, more than 75 bubbles passed (the TEE of course confirmed this).
I had it closed at the end of February with a 25-mm Amplatzer device.
After three months I had my check with another transcranical color doppler echography and still about 30 bubbles passed but my surgeon said I could have began diving again, slowly, if I wanted.
And so I did. I dived NDL dives within 30 meters until last week. Now that I am almost over with my 6-month period, I tried a decompression dive in open circuit. 46 meters in air with a 35 minutes deco time, totale dive time 67 minutes.
And guess so: I started feeling bad after an hour I surfaced, not as bad as I was used to be before but still with a terrible cutaneous DCS (not to go to the hospital but not nice at all).
Yesterday I called my surgeon to tell him so asking to do my 6-month check (that I did not do) but he calmly said that he is sure my PFO is ok and my problem is another (??).
Now, what else to do? please, don't tell me: "forget about technical diving!"

Ciao.

Nicoletta

jeff h

Nicoletta,

You may want to try something as simple as adding more conservatism to your profile, make sure you're staying hydrated and avoid fatigue.

I've had to do this myself because of old sports and overuse injuries. I know a lot of divers that can cut tables shorter than mine and get out okay but that doesn't work for me. Once I accepted that fact my diving has gotten much more enjoyable.

My condition is different from yours though and I've never had the skin bends so you'll have to decide what works for you.

Better advice would probably be to give the PFO more time to heal. After all you've been through there is no point in pushing it now.

Best of Luck,

-Jeff