Based on the provided sources, it is difficult to determine the exact current total market value of heparin used in clinical settings. However, we can gather some information from the sources to give an overview of the market value and usage of heparin.

Heparin is a widely used anticoagulant medication that is commonly used in clinical settings for various purposes, including preventing blood clots during surgeries, treating deep vein thrombosis, and managing certain heart conditions [2]. It is available in different forms, including injectable solutions and prefilled syringes [3].

The first source, DrugPatentWatch, provides information on the patents and exclusivity status of drugs, including heparin. While it does not directly mention the market value, it can be inferred that heparin is a well-established drug with expired patents, indicating that it has been on the market for a significant amount of time [1].

The second source, a study published in the National Center for Biotechnology Information (NCBI), focuses on the cost-effectiveness of different anticoagulant medications, including heparin. The study highlights that heparin is a relatively low-cost option compared to newer anticoagulants such as direct oral anticoagulants (DOACs) [2]. This suggests that heparin may have a significant market share due to its cost-effectiveness.

The third source, a document from the Centers for Medicare & Medicaid Services (CMS), provides information on the coverage and reimbursement of prescription drugs under Medicare Part D. While it does not provide specific market value data for heparin, it mentions that heparin is covered under Part D and provides guidelines for its usage and reimbursement [3].

In conclusion, based on the provided sources, we can infer that heparin is a widely used and established anticoagulant medication in clinical settings. While the exact current total market value is not mentioned, the information suggests that heparin has a significant market share due to its cost-effectiveness and coverage under Medicare Part D.

Sources:
[1] DrugPatentWatch: https://www.drugpatentwatch.com/p/tradename/HEPARIN
[2] NCBI: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5906253/
[3] CMS: https://www.cms.gov/medicare/prescription-drug-coverage/prescriptiondrugcovcontra/downloads/part-d-benefits-manual-chapter-6.pdf