How many have had a PFO test?

[wetman]

Since i want to do the tech 1 course next year, I've been interested in getting this test and was curious about how many others have had it and how long it took?

steve

[swimndive]

Here's a link that should answer all of your questions. http://www.torrancememorial.org/cartee.htm
When I had mine done the drugs stayed with me for a good 12 hours, so you may want to bring a designated driver.

[Uncle Pug]

my diving doc talked me out of having the test done during my last physical. Needless expense, slight risk with the proceedure itself, little potential benefit.

[wetman]

what were some of the reasons against (and risks)?

steve

[Dr Deco]

Dear wetman:

Neurological Hit . :boom:

When one is attempting to avoid neurological DCS from a PFO, it is important to remember: you must have a hemodynamically significant lesion (i.e., one that is truly large enough to pass gas bubbles; you must have a good gas load, and you must be a “bubbles-prone” individual. That truly limits the field.

PFO Test

There are several versions of this PFO test. They are the good, the bad, and the ugly. A bad test is the transthoracic echogram, because it is really not very sensitive. It may, however, show up “significant” lesions and let the trivial ones pass. No one has checked this yet.

The good test is the transesophageal echocardiogram, but it also the ugliest. It is costly and requires time because of sedation.

A good test that is not ugly is transcranial Doppler (TCD) ultrasonography of the middle cerebral artery (MCA). This will tell a “hemodynamically significant lesion.” The unfortunate part is that it is really not done in the US. The best procedure is to avoid the problem altogether. .

The PFO

The presence of a PFO is not necessarily a bad thing, since a large percentage of the population has one. A PFO is in about 25% of the diving population, and a “resting PFO” ( that is, without a Valsalva-maneuver is in 10%. That does not mean that this PFO is significant.

We had a test subject at NASA who had a resting PFO while recumbent, and a high Spencer precordial bubble grade of IV (the highest). When we but a TCD device on his MCA, there was a very good blood flow sound but absolutely no bubbles were detected.
________________________
Powell MR, Norfleet WT, Kumar KV, Butler BD. Patent foramen ovale and hypobaric decompression. Aviat Space Environ Med 1995 Mar;66(3):273-5

Gas microbubbles were detected in the left ventricle of a supine subject being
screened for an atrial septal defect as a participant of a hypobaric
decompression study. This determination was made using the saline echocontrast
procedure. We found provocation by a Valsalva maneuver not to be necessary in
this individual for right-to-left passage of contrast microbubbles into the left
heart and middle cerebral artery. When this same individual underwent hypobaric
decompression to a simulated altitude of 21,000 ft, numerous gas microbubbles
were detected in the right heart, but no gas bubbles were detected in either the
left ventricular outflow tract or in the middle cerebral artery. This
observation appears to be a novel finding, not previously reported.
____________________________

My personal recommendation? Do not perform any Valsalva-like maneuvers while climbing into the boat and save your money.:mean:

Dr Deco :doctor:

[Josh Levinson]

I hate to sound ign'ant and all, but what's a PFO? You guys are starting to freak me out. Thanks.


Josh

[roakey]

Overview: http://www.amplatzer.com/physicians/pfo/defect.html

Real live picture: http://www-medlib.med.utah.edu/WebPath/CVHTML/CV115.html

Ok, maybe not live :)

Roak

[Josh Levinson]

Thanks.


Josh