From your latest post it understood that:
1. Hospital doctor felt the need of interventional procedure and looking into the condition of the patient the patient was shifted to cath lab and since stent was readily available, procedure was completed and life threatening situation was averted.
"One human life is heavier than the earth"
Hospital has given the itemized bill and has shown the cost of the stent separately and hence has stated they have done what was needed to be done.
For indoor patients (including critically sick) hospital has its own pharmacy, and patents are given medicines from in house pharmacy (including late hours when the outdoor chemist shops are closed) and cost of medicines is reflected in the discharge bill. The pharmacy is helps to save precious time during critical conditions.
Some hospitals asks the attendants to replace the medicines given from pharmacy, and issues the Rx and patient can take the bill from shop for reimbursement.
The stent covers, having the batch number etc and cost are with you. High quality stents, drug induced stents are imported and their costs are in currency of country where these are manufactured. The stents are imported by Indian company and they paste stickers of their name etc and cost in rupees.
Hospital has charged more than MRP or less? If how much % less than MRP. Usually in India,16-18% is the margin for retailer,8-10% fr stockist,1-2% for CA/CFA etc. Hospital buys direct from company and is usually supplied thru CA/CFA in the same state.
Unfortunately PCR (Price Control regime) is not happening and stents are not in controlled price category.
The cath lab reports show stent was implanted.
2. The TPA is asking for the bulk purchase bill from hospital, which is not in your control.
Hospital shall not want to make the bulk purchase bill, a public document. Stents are highly profitable item.
At the most you can submit a representation to the hospital and enclosing the TPA's letter and ask to respond and satisfy the insurance company.
At the same time you may reply to TPA that in itemized bill cost of stent has been mentioned and bills submitted by you are in order, hence nothing is pending to be done by you. More over you have done additional work which other wise is not your liability, and have submitted the letter of TPA to hospital, but your claim can not be withheld, since you are not withholding anything.
If TPA has not pointed out anything else, it implies rest of the claim is in order. Still try and obtain a letter that stent is the only query/objection raised.
3. This seems to be cockfight between TPA and hospital.
4. You strongly raise your voice to hospital, insurance company (thru local office and let them exchange communications to wriggle you out of situation), TPA and demand your money, and give a maximum time of say 15 days.
5. The options of legal notice, Insurance ombudsman (since their local office is in your city you can even visit them), consumer forum have already been suggested by learned members/experts.