Hi, I'm Doctor Robert, a Medical Internist (MD) who deals with diseases of all organ systems. All my education has been completed in the US.

Yes, this COULD be angina. A. fib is a rhythm that needs to be treated ,and that you are going into it irregularly needs a thorough investigation.

Have a look at this great website for more information about this issue than I can possibly type myself:
http://www.mayoclinic.com/health/atrial-fibrillation/DS00291

So, this is my plan:
1. See your primary care physician immediately.
2. he may set you up with 24 hour ambulatory electrocardiogram (EKG) monitoring with a Holter monitor.
3. You need an echocardiogram to assess the valves and left atrium. This is almost mandatory for you.
4. SMOKING is the most common non-cardiac cause of atrial fibrillation (AF, or a. fib) and needs to be stopped. Immediately. I'm serious.
5. Given age over 40 with smoking, this could be Coronary Artery Disease (CAD) and also needs to be investigated.
6. Your thyroid needs to be checked with Thyroid Function Tests (TFTs) as this can cause atrial fibrillation (AF, or a. fib) if elevated thyroid function is found. This is a common cause.

Realize this please: I am limited to the information that I glean from your posts, as I can't see, talk to, or touch you. I can only give you my approach to the evaluation of your symptoms if you were in my office. That puts me at a disadvantage compared to your doctor who actually sees your body right there in the office. This is just the nature of advising across the internet. A specific diagnosis under these conditions is VERY difficult.

So, I cannot give you a definite diagnosis. But you have to have this evaluated. It COULD be chest pain from Coronary Artery Disease (CAD) and if that's the case, this is troubling. If you get chest pain again, feel free to go right back to the ER.

That's the straight scoop. See the primary care physician again asap and get this evaluated. It is not in your interest to wait until another episode.

Print this out and bring it with you so he can get an idea of what I think.

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