My cardiologist office only offers the standard Laying flat that you do two times for about 20 minutes lying flat with your head sticking out of the machine. I am very uncomfortable lying flat and have claustrophobia. A friend of mine shared that there is another option, and you have to search around for a cardiologist that might have it. It is much quicker (ten minutes) in the chair than the other apparatus.
I found a cardiologist in my area that was not part of my medical provider, but insurance covered the test per my anxiety. I just wanted to pass on that there are two options for the nuclear stress test if suggested by your cardiologist. If you would like to see the upright chair, google nuclear stess test upright and you will be able to find an image of it.