Mechanical Valve or Biological Valve? Which One for Which Patient?

One of the most important decisions we face when valve replacement is needed is which type of prosthetic valve will be used. In this article I will describe the difference between mechanical and biological valves and the basis on which we make this choice.

The Lifespan of Mechanical Valves and the Obligation to Use Blood Thinners

Mechanical valves are produced from metal and carbon-based materials and, when used correctly, can last a lifetime; for this reason they are an attractive option in young patients. However, in order to prevent clot formation on the valve surface, they require lifelong, uninterrupted use of a blood thinner (warfarin/coumadin) and regular INR monitoring; missing this medication or setting the dose incorrectly can lead to serious consequences.

Biological (Animal-Derived) Valves and Their Advantages

Biological valves are usually produced from bovine or porcine heart tissue and carry a much lower risk of blood clotting than mechanical valves; for this reason, in most patients they do not require lifelong blood thinners (only for the first few months). On the other hand, they can wear out over time, more rapidly in young patients in particular, and may require replacement again within 10-20 years.

Valve Choice According to Age and Lifestyle

Current guidelines define the 50-65 age range as a “grey zone” and recommend that we personalise the choice according to the patient’s willingness to take blood thinners, bleeding risk, pregnancy plans (in female patients) and lifestyle. While in young and active patients the long lifespan of a mechanical valve may be attractive as long as they can take on blood thinner monitoring, in patients of advanced age a biological valve becomes the more suitable choice, since remaining life expectancy generally exceeds the valve’s wear-out period.

Frequently Asked Questions

If I have a biological valve, will I not need blood thinners at all? Generally they are not needed beyond the first 3 months; however, if you have an additional condition such as atrial fibrillation they may still be needed.

Does a mechanical valve always last longer? Yes, when used correctly mechanical valves can last a lifetime, whereas biological valves can wear out over time.

Can I change my valve choice later on? The decision on replacement is made together before surgery; however, when a biological valve wears out, in some cases a new valve can be placed inside the old one by angiographic methods (valve-in-valve).

Conclusion

The choice between a mechanical and a biological valve is a personalised decision we make together, according to your age, your lifestyle and your preference regarding the use of blood thinners. Both options have their own particular advantages and disadvantages.

You can book an appointment for a detailed examination so that we can assess your valve type choice together.

References

1. Otto CM, Nishimura RA, Bonow RO, et al. 2020 ACC/AHA Guideline for the Management of Patients With Valvular Heart Disease. Circulation. 2021;143(5):e72-e227.
2. Whitlock RP, Sun JC, Fremes SE, Rubens FD, Teoh KH. Antithrombotic and Thrombolytic Therapy for Valvular Disease: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012;141(2 Suppl):e576S-e600S.