bioprosthetic

Bioprosthetic refers to a prosthesis made from biological tissue rather than synthetic materials. Bioprosthetic devices are derived from animal tissues (xenografts) such as porcine valves or bovine pericardium, or from human donor tissue (allografts). They are treated and processed to reduce immunogenicity and improve durability.

The best-known examples are bioprosthetic heart valves used to replace diseased aortic or mitral valves. These valves may be constructed from porcine or bovine tissue and mounted on a frame (stented) or designed to be frame-free (stentless). Bioprosthetic conduits and patches from donor tissue are also used in congenital heart surgery and vascular reconstruction.

Manufacturing and processing involve fixation of tissues with agents such as glutaraldehyde, sterilization, and anti-calcification or anti-immunogenic treatments. Recent approaches include decellularization and methods to reduce calcification.

Advantages of bioprosthetic devices include little to no need for long-term anticoagulation, lower risk of bleeding compared with mechanical valves, and satisfactory hemodynamics. They are often preferred in older patients or those with contraindications to anticoagulation.

Disadvantages include limited durability, with structural valve deterioration typically occurring after about 10 to 20 years depending on patient age and valve position. Younger patients may require repeated intervention. Other risks include calcification, infection, and rare immunologic responses.

In clinical practice, choice between bioprosthetic and mechanical prostheses depends on age, comorbidity, and lifestyle. Advancements in transcatheter valve-in-valve therapies and ongoing tissue engineering aim to improve durability and expand indications.