Final answer:
A patient with a prosthetic valve replacement requires lifelong therapy with anticoagulants to prevent blood clots and ensure the proper functioning of the valve.
Step-by-step explanation:
A patient with a prosthetic valve replacement requires lifelong therapy with anticoagulants. This type of medication is essential to prevent blood clots from forming on the prosthetic valve, which could lead to serious complications such as valve malfunction or infection. Anticoagulants thin the blood and reduce the risk of clotting, ensuring the proper functioning of the prosthetic valve.