Unable to diagnose. Ct angiogram done.

Hello, My husband is getting a sharp pain on his left side of the chest, right under the heart region and it radiates on his side towards his back , his left arm to his wrist. He complains about a squeezing sensation in his wrist and also his throat which comes and goes. It went on for 2 hours the first time, We have given him ULTRACET and it reduced after an hour. this keeps happening frequently , the sympotms vary a bit and ranges from half an hour to 2-3 hours sometimes. We checked with his allergist, cardiologist, orthopedician and also a gastroenterologist. But no-one is able to give us an idea on why this is happening. To tell his medical history, he started having irregular heart rate and  since June 6, 2021. he is diagnosed with inappropriate sinus trachycardia after we had 24 hrs ECG monitoring for 5 days. in parallel, his allergy screening test revealed he has allergy to food and environmental items which we have been avoiding completely. we got his CT angiogram done.