Results from stress test and morning issues

I am 39 yrs old, 5'2" 200lbs, with a history of heart disease in my family. I had an Echo 2D M-Mode C/Full Doppler in July 0f 2008, because I was experiencing shortness of breath and chest pressure/pain. The conclusions said "normal echocardiogram", but as I was reading the full report under the Left Atrium heading it says, "The left atrium is normal in size. The interatrial septum is aneurysmal." What does that finding mean??  The reason I am am concerned is because for the past month I have been waking up in the morning with my chest aching and the feeling like I am holding my breath. The feeling lasts for a couple of hours. What are they symptoms of that finding? I was tested for sleep apnea and it was negative. My doctor just says maybe I am sleeping funny or it's anxiety. But I have suffered from anxiety before and this is a completely different feeling, and I have changed my sleeping position. Should I consult a cardiologist? Any advice would be so helpful.

[Cleveland Clinic]

It means that the membrane between the top chambers of the heart is moving from one side to another. This can mean that you have an opening between the two chambers and it also means that you are at an increased risk for a stroke. In our experience we usually perform a bubble study to resolve the first issue, and place the patient on at least a full dose of aspirin for the latter.

[michelle23]

I forgot to mention I take Protonix 40 mg a day for suspected GERD.

[michelle23]

That is quite concerning since these results came in July of last year and my Doctor didn't order any follow up test or advise me to take aspirin. I am going to consult with a cardiologst.