spasms, shortness of breath SVTs

For years (i'm 64, male) I have suffered from 'stomach' problems like spasms which feel like something is in there twisting and suddenly pushing up into my lower chest under the breastbone. Lately When this happens I have been getting very breathless and hav often experienced heart 'miising beats' and SVT's. I have been to the ER several times and have been diagnosed with a sliding hiatus hernia, duodenitis(?)  and the opening from my stomach to my duodenum is narrowed. I get strong reactions to acid foods but sometimes its the opposite - I need something acid to feel better. I take Aantac and for the past 2 years Tenormin for heart rate regualtion plus Micardis for high blood pressure. When I really feel bad I take Ducene (2mg) and the spasm feelings stop after a while. Whenever I reach up over my head or twist to the side (washing car etc) I usually get 'spasms' and sudden breathlessness, and some moderate pain in the upper abdomen. Its all worse when i am stressed over long periods and when my back pain (ankylosing spondilytis) is bad. Pain refers around to the cartlidge between my ribs and inflames it.
I have had numerous tests over years but can't get rid of this. Some days I'm fine, but they are few. I wonder if the Tenormin is upsetting my stomach? I'm ultra sensitive to drugs that way. Any ideas will be gratefully received. Thanks a lot.

[CalGal]

Zantac can cause heart conduction irregularities. You may want to talk to your doc about its possibly contributing to a part of the problem.