This is a tough one because we don’t really have a perfect replacement valve at the current time. This is one of the reasons why with mitral valve disease, I believe so strongly in repair as the first option for the vast majority of patients. For those limited number of patients for whom a mitral valve replacement is necessary, the options are a tissue valve (cow or pig usually) or a mechanical valve. Mechanical valves require a blood thinner called coumadin which has a 1-2%/year risk of significant bleeding or stroke. Of course, this depends on the patient and how closely they monitor their levels (INR-a measure of “blood thinness”). The advantage of a mechanical valve is that it can last for a lifetime although this is not 100% true-occasionally we do have to replace a mechanical valve that fails. A tissue valve has the advantage of not requiring coumadin long-term. However, it will fail over a period of time. Typically we tell patients 10 years in younger patients and 20 years in older patients. However, the truth is that it’s hard to know. I have seen tissue valves fail in 2 years and last 25 years. It depends on the patient. Younger patients with tissue valves tend to have them fail much more quickly. This is tough because younger patients are often the ones who want to stay off blood thinners. Most women who want to bear children should avoid mechanical valves and coumadin. There is a lot of talk about the ability to replace a failed surgically placed tissue valve with a catheter valve (TAVR) device. This is true and is currently being done. However, it is still a major procedure and we don’t know much about the durability of these procedures and how many times it can be done. With this procedure the old valve is left in place so one would assume there are only so many times this can be done.
There is hope on the horizon for tissue-engineered valves but nothing currently available and I would not advice delaying surgery because we have no idea how long these long-sought after valves will be available.