sadiesoo,
It sounds like your shortness of breath is really affecting your life. The doctors have done a very good job of testing and have covered most of the important things. I assume that the COPD test that you refer to was a Pulmonary Function Test (PFT) - if not, that should be considered as well.
It is difficult to comment on the contribution of coronary artery disease to your shortness of breath without being able to look at the actual pictures. With that caveat, your doctors performed a type of stress in the cath lab which suggests that the blockage in the LAD is not limiting the amount of blood which is being supplied to you heart.
Your echocardiogram showed evidence of diastolic dysfunction which can certainly cause you to become short of breath. There are few good therapies for diastolic dysfunction other than controlling your blood pressure, watching the amount of fluid and salt that you take in.
While you are continuing to work on these things, I would suggest that it would be a good idea for you to begin a structured exercise program. You will likely be limited when you first start but with patience and persistence you may be able to regain more functionality.
I hope that this helps.
I had a Pulmonary function test , results were clear lungs 93% o2, my bp runs 183/ 108 to 98/ 78 with a resting pulse of 112- 125. I have always been very active and still try to maintain my excerise, i just have to stop every 6-10 minutes and catch my breath, this takes about the same amount of time. When I run out of air it feels like I am fighting for air. I have small chest pains everytime I do excerise. I take nitro about 4 times a week. The heart Dr just recently took me off metoperol, he sad maybe it was causing my shortness of breath, I had the shortness of breath before ever taking this medication and I'm sure that is why my heart rate has jumped back up again. Before medication my bp was 150/110- 186/ 132