Aneurysm Atrial Septal Wall w/shunting..need help understanding

Yes Im 25 y/o M in hte army.  Make a long story short.  Got stationed in VA and my run times started getting worse cause at the .5 mile mark Id feel like I was going to pass out.  Had a series of test and was DX:

1.aneurysm atrial septal wall
2.patent foramen ovale

*bubble study performed for cardiac shunting and study was positive.

I havent had my f/u with the cardiologist till next week and was hoping someone could help me better understand this.  Ive googled both but continue to get crazy amounts of info that just doenst make any sense. Please if anyone has any information about both DXs and what SHUNTING means  please share.  Im somewhat worried but at sametime unless I know something for sure Im not going to worry about it.  Dont be scared to be the bearer of bad news.  Let me have it.

Thank you for time

[kenkeith]

Thank you for serving!

For some insight most patients with a patent foramen ovale (PFO) as an isolated finding receive no special treatment.  An aneurysm of the septal atrial wall is a bulge due to a reduced thickness of the wall that separates the upper and lower heart chambers.  Increased pulmonary pressures can exacerbate the problem, and the problem as it relates to a right to left shunt is that some blood that should go to lungs from the right side of the heart goes into the left side (hole between the right and left atria) that has oxygenated blood to be pumped into circulation. As a result the blood oxygen level can be reduced to the extent the low blood/oxygen compromises an adequate supply to the system causing shortness of breath, etc. Also, there is a risk of blood clots as the blood may pool in the left atrium.  The risk of stroke increases In patients with atrial septal aneurysm and PFO.

Surgical closure of PFO is indicated if the PFO more than 25 mm in size and quantification of the PFO shunt volume is determined by contrast injection at rest and during Valsalva-Maneuver. A "small" shunt volume was defined as 3–20 bubbles and a "large" shunt volume as 20 bubbles passing the PFO into the left atrium. That is the procedure you state you had (bubble test)..

An ASA (atrial septum aneurysm) is  defined as an interatrial septum of abnormal mobility with protrusion of the septum into the left or right atrium of at least 10 mm beyond baseline.  If you have your report, you can determine degree of abnormality.