PFO-An open letter of thanks to George Irvine (long)

[detroit diver]

Well, mine was called a CardioSeal. I think it's made by Spencer Medical. I don't think the diving population will increase sales by that great of an amount. They do many of these each week and almost none are diving related.

The problem with risk numbers is that there is no central database for data collection. That has been a problem for many years. Without good data, DCS risk numbers are meaningless.

My answer to the risk of surgery is to find a surgeon that does many of these procedures. You don't want to be his first or 10th case. One of the side benefits of having it done it that you reduce your risk of stroke. Not necessarily a reason for the procedure, but coupled with the diving issue it certainly gives more weight to the decision.

Jack,
Great post. Glad you're doing well!
If 30% have a PFO and suddenly everyone is getting checked... where do I buy stock in the thing they use to fix it?? There's gonna' be a lot of PFO surgery goin' on.
If the risk for DCS is only 0.010, what is the risk for the surgery? Even minor surgery has some risk to it. Maybe it's less than 0.010, in which case we may have another one of those, "The most dangerous part is the DRIVE" things going on here. Out of the relative few scuba deaths each year, only SOME of these are unexplained, and maybe SOME of these are PFO related, but it sounds like we're into Lottery odds here, and I'm not sure if having someone poking around in my heart is worth it.
But then, this could just be my over developed denial mechanism kicking in...

 

[detroit diver]

I need to make one change in my report. Apparently I reversed the left and right side chambers when describing the blood flow. Thanks to those that corrected me.

 

[glbirch]

Jack,
Great post. Glad you're doing well!
If 30% have a PFO and suddenly everyone is getting checked... where do I buy stock in the thing they use to fix it?? There's gonna' be a lot of PFO surgery goin' on.
If the risk for DCS is only 0.010, what is the risk for the surgery? Even minor surgery has some risk to it. Maybe it's less than 0.010, in which case we may have another one of those, "The most dangerous part is the DRIVE" things going on here. Out of the relative few scuba deaths each year, only SOME of these are unexplained, and maybe SOME of these are PFO related, but it sounds like we're into Lottery odds here, and I'm not sure if having someone poking around in my heart is worth it.
But then, this could just be my over developed denial mechanism kicking in...

My thinking is, have it looked into. If I don't have one great, if I do then I'm at least aware of it. If it's really small, don't worry about it for now, if it's bigger I need to make a decision. I am thinking of moving into more technical diving, so if I do have one I can at least look at my options. If nothing else, a negative test would provide peace of mind for my piece of mind.

 

[Rick Inman]

Just went for coffee in the kitchen, noticed the new March/April copy of Alert Diver mag (from DAN) on the counter, riffled through it and, son-of-a-gun, there's and article on a guy getting bent due to a PFO. Check it out, it's titled, Bent, But How?

 

[Uncle Pug]

DD... you need to eat more geoduck for a speedier recovery. However it might be cheaper to ship you out here. We will put you to work as a live boat driver for the next 2 months until you can get into the water again.

BTW: I am surprised the PFO test I gave you at Hat Island didn't show up positive. Swimming hard chasing the anchor and then trying to haul yourself back aboard the boat should have been enough to give you at least a niggle or two.

 

[Saturation]

Most divers hit and likely have PFOs worth examining have been hit early in their dive careers, most all in recreational dives. Most hits are non-lethal, just mild DCI2 with numbness, tingling, weakness that resolve on recompression.

Treatment of a PFO with cath based umbrella has a risk of death or injury greater than the risk of DCI in the diving population. The DCI data is from so many sources over 30 years, with roughly unchanged rates, 1-10/1000 divers across different data bases, workers and countries that is essentially carved in stone. The injury risk from cath is at least equal to or 10X that of DCI and that is the baseline risk for having this procedure done by the BEST docs doing this.

I wont even discuss the risk of open heart surgery for PFO closure.

After having a button or umbrella closure, patient is exposed to complications associated with this device such as incomplete closure, leaking and forming blood clots that can stroke the patient WITHOUT diving.

The 'window' of safety post procedure occurs once the device has settled in, and that is a month after the procedure at minimum. If the device doesn't form a tissue covering completely, patients can throw emboli from the umbrella. As prevention, most closures require patients to take aspirin, or worse, warfarin, potentially lifelong.

http://www.ncbi.nlm.nih.gov/entrez/...ve&db=PubMed&list_uids=14708946&dopt=Abstract


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Abstract&list_uids=9412617


Even if closure is up to 95%+ successful, strokes still occur. An 2D echocardiogram checks for good positioning but only a repeat bubble contrast TEE can check for leaks. Further, just as clot strokes can come from other sources, so can gas emboli. Heavy gas loads can pass through lung shunts or de novo bubbles form within CNS tissue.

The only justification for enduring such complications, LARGE expense and long term follow up is if the PFO is so large it that can be heard by physical exam [such divers wouldn't even pass the physical requirements for basic OW], or because patient has had a prior DCI2 episode and wishes to dive. Then, all risk reducing procedures and methods are employed because what had a chance of happening, HAS indeed happened. Until then, "don't fix what ain't broke."

A bit old, but the fundamental argument is still there:

http://www.aquanaut.com/bin/mlist/aquanaut/techdiver/display?48728,from

 

[detroit diver]

DD... you need to eat more geoduck for a speedier recovery. However it might be cheaper to ship you out here. We will put you to work as a live boat driver for the next 2 months until you can get into the water again.

BTW: I am surprised the PFO test I gave you at Hat Island didn't show up positive. Swimming hard chasing the anchor and then trying to haul yourself back aboard the boat should have been enough to give you at least a niggle or two.

I keep looking back at some of my experiences with you and wondering how my PFO didn't show up! Must have been because of who I was with...

That geoduck is really fantastic. I might have to take you up on your offer!

 

[Groundhog246]

The problem with risk numbers is that there is no central database for data collection. That has been a problem for many years. Without good data, DCS risk numbers are meaningless.

That's where the Abacus Project being run in BC shines. The BC diving council (not sure if that's it's correct name) came up with the idea that by and large, 1 air fill = 1 dive. They put together a reporting program for fill stations in BC (and had a very high participation rate, although not 100%) and got some fairly accurate figures for the number of fills. They have always had figures for the number of "treated" dive injuries. Putting it together they finally had some hard numbers on which to base risk. As a previous poster pointed out 14 cases of DCI from 146,291 tank fills (i.e.) , an incidence of only 0.010% and if I recall correctly there were 2 or 3 deaths.

 

[detroit diver]

Just went for coffee in the kitchen, noticed the new March/April copy of Alert Diver mag (from DAN) on the counter, riffled through it and, son-of-a-gun, there's and article on a guy getting bent due to a PFO. Check it out, it's titled, Bent, But How?

How's that for timing!!

 

[BigJetDriver]

DD,

I'm glad you are doing well and will be back to the sport you so obviously love very soon. Thank you for giving us the "inside the patient" story.

I am also glad to hear that George did you some good. I have, at times, been scolded (along with a bazillion other people) for criticizing George. I would have to say that George has done a lot of good for the tech diving world. If he could only come to understand that "tact" is not something with a flat end and a pointy end that you jab into things, there wouldn't be so many people down on his case.

IG,

Thank you, as always, for your learned and scholarly input. We have a desperate need in our sport for people who have an education and training such as yours, who are experienced divers, and are willing to freely share such hard-earned information. Again, thank you!

BJD