Mechanical and tissue valves each have specific advantages and disadvantages.
If a mechanical valve is chosen to replace your original valve, you will need to take Coumadin® after the procedure for the rest of your life. Coumadin helps prevent blood clots from forming on the new valve. With Coumadin, you will also need to have blood tests on a regular basis. This will help your doctor adjust your dose of the Coumadin so that it is appropriate for you.
Taking Coumadin can require lifestyle adjustments such as giving up: contact sports, skiing, or even an occupation that requires physical activity. Because Coumadin decreases the ability of the body to clot its blood, it has a risk of causing bleeding in other parts of the body. This usually is related to some trauma such as a fall or accident. However patients on Coumadin can also bleed without trauma. This bleeding may be seen as a nose bleed, in one's stool or urine. This can also be noted as easy bruising but can be as serious as a stroke. While taking Coumadin there is approximately a risk of 1 patient out of 100 each year that may have a stroke or a bleeding complication.
The advantage of a mechanical valve is that it may possibly last the rest of your life.
Tissue valves have the advantage of not generally needing a long-term medication like Coumadin. The disadvantage of tissue valves is that they usually do not last as long as a mechanical valve. They will last on an average of 10 - 15 years before they need to be replaced with another valve.
Tissue valves also have a risk of stroke after they are implanted. Certainly their risk is much less then a mechanical valve but a few patients per one thousand can have a stroke with a tissue valve. For this reason, some surgeons will place patients with tissue valves on Coumadin for 3 months after surgery. However the risk of stroke with a tissue valve in the long term is far less than a mechanical valve.