db128,
I've learned that most of us w/TOS, tend to rotate our shoulders inward, and rest our arms in our laps. This is the most "naturally" comfortable position with TOS.
But,
If you have heart issues as well, I' not a doctor, therefore, and even if I were a doctor, I' want to be SURE about my heart!
As a matter of fact, my own Doctor had a HAttack recently, and he told me of the "Elephant on the chest" feeling.
That's a far cry from TOS.
Apparently I don't live so far from LinJane, and the cold rainy weather here, took me out today, too.

Just be sure, OK?
This is a question you should ask your doctor.

ASB
Pete