Brief Answer:
See the description

Detailed Answer:
hello,
This doesn't look like a cardiac pain. Cardiac pain typically occurs on exertion and decrease with rest. Pain of heart attack would be very severe, not persist for a week and also ecg would show changes.

Mostly it's a gastritis and reflux disease. Does he also has upper abdominal pain, nausea, bloating, burping, increase in pain on food, sour water feeling in throat, if yes these are the other symptoms of the same. He should avoid fatty, oily and high spicy diet. Have some walk after having food instead of taking rest. Have multiple small meals instead of heavy meals. Have regular sleep habits and avoid stress. Elevate head end of the bed during sleep and rest. Lots of green leafy vegetables, fruits. Avoid smoking and alcohol if any.

He should strictly avoid Voveran as it can increase the gastritis. Instead for pain he can
-Tab dicyclomine 20 mg or hyoscyamine 10 mg whenever needed upto two to three times a day.

As he is not responding to pantoprazole, he should get prescribed
-tab Rablofit DSR 20 mg (Rabeprazole plus domperidone) before breakfast once a day for 2 weeks. -Also, Plain Tab Rablofit ( Rabeprazole) 20 mg before dinner for a week.
-It will take some time to respond. Also, he should take Syrup Sucral O two teaspoon three times a day for a week.

Besides, this he should have a healthy lifestyle like avoiding fatty, oily and high calorie diet. Have low salt diet.

Monitor blood pressure regularly thrice a day for one week then once or twice a week. If bp is persistently more than 140/90 mmhg, then you should be on medicines for it.
Regular exercises like brisk walking, jogging according your capacity atleast 30 min a day and 5 days a week. Avoid smoking and alcohol if any. There shouldn't abdominal fat deposition or obesity.

He should also get prescribed lipid controlling drugs like Atorvastatin 10 mg bedtime., for his mildly deranged lipid profile and also because he is diabetic.

After this pain is controlled, he should undergo treadmill test for heart evaluation. So get back if you have any further doubts.

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Brief Answer:
See the description

Detailed Answer:
Still reflux disease can be kept as the first possibility. Try Syr Sucral O or gelusil, if it's providing some relief then it supports the diagnosis, otherwise we need evaluate for the other causes of chest pain as well.

We need to repeat the ecg, get CKMB and troponin I test done, these are basically test to rule out heart attack. Also, chest X-ray and echo should be done.

You please upload the snapshot of ecg just to confirm that it's not having any changes. Are there any other symptoms, relation with breathing, any back pain, any pain on giving on pressure, any factors which increases pain and relieves pain.

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