Shadow On Peripheral Vision Giving Tunnel Effect. History Of Open Heart Surgeries. Which Doctor To Co Sukt?

Yes, I am wondering if I need either an ophthalmologist, or optometrist due to a condition I've had for years that has not been very obtrusive on my daily life, but has been a concern. I have what I would call a "shadow" on my peripheral vision, giving my vision a kind of tunnel effect. I can see just fine, but it's a different shade completely. I think I might had a stigmatism as well...

I've had two open heart surgeries, (I'm 34 small framed female) and I've been told that sometimes eye damage can result from low oxygen.

Since I think I need glasses anyway from eye strain, I want to know what sort of doctor I should see, and if this condition is common.