Possible PFO: Advice?

[katbattt]

I've been a recreational diver since 2008, made my way up to Divemaster and now have over 120 dives. Recently been thinking more and more that I might have a PFO and need some advice. Sorry for the long post, just thought it'd be better to post the whole story. I'm going to talk to LDC soon to see what they say.

A few years ago, I was based in Indonesia for 6 weeks for scientific diving, and had some issues at the end of this with anxiety that started off on a dive around 17m in quite a strong current. A few more dives at similar depths but without the currents and I was continuing to be anxious and tight chested. I put it down to tiredness/stress from completing a project in an alien environment for a long period of time. Also was anxious about being anxious if you know what I mean, because diving was a big part of my life and I couldn't understand why I was struggling. Dives got progressively worse, with a couple of panic attacks. The final dive of the trip: anxiety near the end of the dive (around a 15m profile for 45 mins from what I remember), slow ascent to safety stop, where I had another panic attack, was brought up by the two guys I was with, the dive leader on the base and my supervisor, but I fell unconscious just below the surface. They gave me O2, no other issues on that trip. Back in the water a few months later in the UK with my instructor with no issues, so put it down to the stress of the trip. My supervisor at the time did suggest that the problems might have been caused by a PFO, but the lack of issues before/since made me question that so I didn't do anything about it.

Previously the only issues I'd had was on the deep dive of my Advanced OW training; I felt breathless/tight chested once we got down to 30m and had to ascend. Then I've always felt quite breathless below ~20m, which I just thought was due to the density of the air and have always really concentrated on my breathing since. That and headaches post-dive, the most intense being in Majorca after 30m/20m diving morning and afternoon but always well within recreational limits with safety stops, normal profiles and slow ascents. It was suggested that they were "CO2 headaches" caused by a buildup of the gas in my system. I don't really hydrate that well day to day, so thought it might also be dehydration (although felt different to the headaches I can recognise as dehydration normally).

This year I've done a lot more diving than any other year - we joined a new club so have been tagging along to UK trips. The first of the year was a trip to Swanage, ~25m, I immediately felt the same breathless feeling and tight chest once we reached the bottom. Calmed a bit throughout the dive but it was always persistent. I have an adjustable regulator and had it on maximum flow (that basically always flows a little so I barely have to pull to get a breath) and still didn't feel right. Multiple dives on multiple weekends since, absolutely fine until I get below ~20m, then I get this feeling. Post-dive I'm tired, more tired than my mum, and I'm a lot fitter and stronger than her so seems weird. I run twice/three times a week and do yoga and weights frequently, so you'd think I'd be ok. Still quite a few headaches.

So: CO2 headaches would make sense if the gas was bypassing my lungs, would also account for the feeling of breathlessness if I have a high concentration of CO2 flowing around.
Never had the bends - I dive with my mum and we are always very conservative so might just have been lucky. Post-dive stress is always minimal because I'm the little one in the club so everyone tends to help me out.

Non-diving symptoms: very often get headrush just from standing up (also have slightly low blood pressure so put it down to that).
Also really struggled on a recent skiing trip with breathing due to altitude.

 

[sheeper]

There is a lot of debate and even conflicting data on PFOs in the dive medicine world. Bottom line is to check the current research with DAN and get a referral to a cardiologist with a background in dive medicine.

 

[beester]

Reading what you are saying I would also looking into CO² hits as the cause of your issues and not PFO. Anxiety can affect how you are breath and it can be a catch 22, where you are anxious, have a bad dive, which will enforce the anxiety on the next dive... etc, etc. CO² hits are not related to PFO as far as I know.

PFO: is basically a shunt (bypass) in your heart which can potentially move small bubbles from your venous system to your arterial system. There are many more shunts possible (in your heart, but also for example in your lungs), and there is a lot of research which is not really conclusive on it's effects on diving. DAN is a good source of information so if you have dan insurance contacting them for a checkup with someone they suggest is worth a try. A PFO can cause DCS or make an existing hit worse. Your episode of fainting could be a DCS hit but not enough info. Finally there is a link between migraine and PFO, but this is not dive related.

CO² build up: which can happen because a bad breathing patern (skip breathing), your regulator not functioning properly, or outside factors which cause you to strain yourself (current, lot's of equipment, stress, etc), has some very nasty side effects: feeling out of breath, narcosis (specifically dark nark... the impending feeling of doom), headaches. Once you have a CO² hit underwater there is not much you can do except, stopping what you are doing, and focussing on slow and long exhales and short inhales (same as you would to counter hyperventilation). However in many cases if you get a CO² hit it can really take a long time to get rid of it's effects. Sometimes even hours after a dive.

What I would do is identify what is the cause of all of this. And go from there. If you feel already stressy before a dive, look at what is causing it and try to remove that factor next time. For example:
- I'm feeling out of breath before a dive: If possible take your time to catch your breath before descending, a couple of minutes hanging in the water, just for you to catch your breath will calm you and will let your breathing settle down again. Maybe you can also aleviate some of the causes of being out of breath. Maybe ask help for you to kit up, or take up sports (although I read you do that).
- I'm feeling stressed about a 30m dive: Well build up slowly... it's a hobby it's supposed to be fun... no need to go to 30m if you already know you are going to be stressed about it.
- I'm feeling stressed about diving with a particular buddy: Dive with someone else.

I would restart my diving, pick a spot good conditions (no current, reasonable to good vis), take a good buddy, take care that I'm not stressed in any way and do some shallow dives and go from there. Also have your regulators checked just to be sure that they are performing as should be.

 

[fmerkel]

The only way to find out for sure is a test. If you seriously think that may be your problem and it's causing you anxiety, I'd say you need to suck it up and get the test.

I know a couple active divers with PFO's. Shortness of breath and anxiety are not issues. One gets migraine headaches if he 'pushes it' the other one simply got bent.

We ALL bubble if microscopically from a dive. The (normal) bubbling happens primarily on the venous return side of the body and if the bubbles are too large they are screened out and dealt with in the lungs. If you have a PFO some may slip by that screening, re-enter the arterial side and get lodged somewhere in the body, the brain being the nasty one.

Personally I would suspect if you've never been bent, skin rash, or anything else of the DCS 'category' you don't have that problem. You may have exercise and stress induced asthma, another thing to worry about. Or as suggested your anxiety is simply messing with proper breathing.

On the other hand if you get the issue only on deep divesI would strongly suggest you take a good look at your reg. Just because it's adjustable to the point of free flow doesn't mean it flows (actually delivers) air properly at depth. My wife's first reg was fine at low stress recreational depths and would not perform under high work loads at depth. Switched to a ScubaPro and the problem went away. But a big part of that is also keeping the stress down and breathing under control. If you FEEL like your ability to breathe is compromised it will be about impossible to effectively deal with that.

Note -the migraine friend has dealt with his PFO issue by always diving Nitrox, avoiding really deep dives and always doing nice long safety stops. That works pretty good for post-dive fatigue also.

 

[Duke Dive Medicine]

Hi katbattt,

From the symptoms you've described, I don't see any indication for a PFO test. PFO is associated with severe decompression sickness symptoms (neurological, inner ear and cutis marmorata), which by definition manifest after decompression. Your symptoms begin on the bottom. Anxiety at pressure could be related to CO2 buildup as beester has suggested, or it could have another physiologic or psychologic cause.

Best regards,
DDM

 

[Imla]

How do you breathe when you dive?
Are you very conscious of your breathing pattern? Trying to save gas?
As DDM, I do not think this is indicative of PFO, but rather of a CO2hit.
CO2 is highly narcotic and is related to anxiety.

 

[Dr. Doug Ebersole]

I am a cardiologist/tech diver/cave diver/CCR trimix instructor who is currently performing a prospective PFO and DCS study in conjunction with Divers Alert Network (DAN). I agree completely with Duke Dive Medicine (DDM) above. Your symptoms do not sound like anything related to a PFO. PFOs are associated with certain forms of DCS (cerebral, spinal, inner ear, and skin bends). Your symptoms sound more like a CO2 problem as DDM mentioned above.