Heart valves play an essential role in regulating the flow of blood through the heart. However, some people are born with heart valve defects or develop issues with their valves later in life due to various causes. In such situations, prosthetic or artificial heart valves provide an effective alternative to damaged natural valves. This article discusses the different types of prosthetic heart valves available and their benefits.

Types of Prosthetic Heart Valves

There are three main types of prosthetic heart valves used as replacements for damaged valves:

Mechanical Heart Valves: Mechanical heart valves are most commonly made of carbon or other durable materials. They have movable parts or discs that open and close to regulate blood flow. Some examples include bileaflet valves and tilting disk valves. Mechanical valves last a very long time but require lifelong anticoagulation medication to prevent blood clots.

Tissue or Bioprosthetic Heart Valves: Also known as biologically engineered valves, tissue valves are constructed from biologically compatible material such as pig or cow tissues. They aim to mimic the structure and function of natural human valves. While tissue valves do not require blood thinners like mechanical valves, their durability is less and they may need to be replaced every 10-20 years. Common tissue valves include porcine valves made from pig tissues.

Valved Conduits: Valved conduits are artificial tubes containing valves that are used when no other option exists, especially in children and infants. They are intended as a bridge until natural heart growth enables standard valve implantation.

Benefits of Prosthetic Heart Valves

Prosthetic heart valves offer several advantages over trying to repair severely damaged natural valves:

- They effectively replace dysfunctional valves and restore healthy blood flow and pressure in the heart. This improves cardiac function and quality of life.

- They are sturdier and more durable than fragile damaged natural valves. Prosthetic valves can last decades with minimal risk of deterioration.

- Risk of blood clots forming on the valve and embolizing is much lower compared to severely damaged natural valves which often cannot close fully. This reduces the risk of stroke.

- Unlike natural valve repair or reconstruction, prosthetic valve replacement is a very standardized and refined procedure with excellent long-term outcomes. Success rates of the surgery are very high.

- Certain types of valve defects or damage simply cannot be corrected with repair or reconstruction. In such cases, prosthetic valve replacement is the only surgical option.

- They eliminate the risk of future valve deterioration which is common with certain types of congenital or rheumatic valve defects. A single replacement surgery treats the problem permanently.

Risk Factors and Complications of Prosthetic Heart Valves

However, prosthetic heart valves also have certain disadvantages and risks compared to natural heart valves:

- Infective Endocarditis: As with any foreign object placed in the body, prosthetic valves carry a small but important lifelong risk of bacterial infections. This risk is higher than for natural valves. Endocarditis requires long-term antibiotic treatment.

- Thromboembolism: Mechanical valves especially have sliding metal or tilting components enhancing risks of blood clots. Lifelong anticoagulants minimize this risk but increase bleeding risks. Tissue valves have lower risks.

- Structural Failure: Tissue valves especially may degenerate faster than predicted and require reoperation 10-25 years later. Mechanical valves can last 50+ years but have no growth potential in children.

- Anticoagulation-Related Bleeding: Blood thinners like warfarin reduce clot risks but increase bleeding risks. Striking the right balance between these two risks requires careful management.

- Valve Removal/Replacement Issues: Should a removed valve need re-replacement, it becomes more complex with higher risks due to multiple open-heart surgeries and more scar tissue.

- Maternal/Fetal Issues: Pregnancy in young women with certain prosthetic types can impact maternal/fetal health due to altered coagulation and increased clot/bleed risks. Careful management is needed.

Prosthetic valves thus require lifelong monitoring and management. However, with proper care, modern prosthetic heart valves provide patients and their physicians an excellent treatment option to prevent premature death from severely damaged and life-threatening faulty heart valves. With continued medical research as well, outcomes will continue improving over the coming decades. Heart valve replacement surgery today saves and improves countless lives worldwide.

In summary, while repairs are ideal if possible, prosthetic heart valves serve as a viable and in many cases superior alternative to permit patients with valvular dysfunction to lead full and active lives. With appropriate follow-up care and medication management when needed, they can typically last decades, even for a lifetime. Prosthetic heart valves exemplify a remarkable triumph of medical technology over fatal cardiac illnesses.