Hi Amy,
I would agree with your theory, but don't have any medical facts to back it up, just my own experience. I had VERY severe aortic regurgitation, and my hands were ALWAYS freezing cold, along with the rest of me. I had a big black sweater at work, and had to take a hot shower before bed in order to stop shivering so that I could get to sleep. After my surgery, I noticed a change - my hands were WARM!! Now that it's summer, it's hard to tell (anyone's hot in 90+ degree weather!) I attributed all this to the circulation problem, or maybe all my energy being used by the heart to pump blood, with none left to provide body heat.
Best wishes for your surgery tomorrow, and you're hubby's too. Hang in there....!
-Jennie