In this medical health video learn what is the difference between Tissue Valves and Mechanical Valves.
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TISSUE VALVES VS. MECHANICAL VALVES Allen Graeve: Replacement valves generally come in two broad categories, Tissue or Mechanical. The tissue kind are usually made out of either bovine or porcine parts. The Bovine pericardium, the cow pericardium is fashioned into leaflets, or in case of the porcine it's the usually the actual pig leaflet that becomes part of the leaflet that is replacement part. John Puskas: Biological valves are removed from animal hearts typically pig or cow valves, and they are prepared on a scaffolding that allows us to sew them into the heart. Allen Graeve: In terms of the tissue valves we don't have a perfect tissue valve, one that last as long. Somewhere between 10 and 15 years we begin to see deterioration of these tissue valves to the point where these valves start to deteriorate, and either the patient is recommended for surgery, or has surgery, or maybe because the patient is now too old, surgery is simply denied. In terms of mechanical valves the first ever mechanical valve really stands from this area was the Star-Edwards valve in Portland and it was really a ball in a cage. It was life-saving for many people, and still is probably in use in a few select places. But it's been supplanted by more successful mechanical replacements. John Puskas: Mechanical valves are man-made valves. They are designed by engineers and manufactured in factories here in America. Allen Graeve: The bileaflet valves have for the most part supplanted valves that just had one leaflet and that leaflet might move up and down, or might move like a door, opening and closing, or move up a strut and then move down. Right now bileaflet valves basically are the mechanical valves. John Puskas: The mechanical valve is a permanent device that never wears out, and the biological valve of course, since it comes from an animal and animals don't live or last forever, they do eventually wear out. There are relative benefits of one over the other though. Mechanical valves, the number one benefit is that they last forever. They do not ever wear out. Allen Graeve: Durability of the mechanical valve is probably life-long for most patients. There are things that could make you replace, or remove a mechanical valve. It can leak around the edge. It can become infected, it can actually become obstructed either by clot or by pannus. John Puskas: Then cause a stroke or a heart attack or other problem, unless the blood is thinned, to prevent it from clotting on the mechanical valve. Allen Graeve: But these things are not inherent to the mechanical nature of the valve. If nothing obstructs it like pannus or clot, if it doesn't become infected, if it doesn't leak around the edge, then it should last lifetime, in fact, last many years longer than the patient has. John Puskas: They do however require a blood thinner. Allen Graeve: There has been no mechanical valve that has been able to be successfully run without Coumadin, deliberately run without Coumadin. There have been some attempts and sometimes people have neglected Coumadin, the blood thinner of choice has it right now for all mechanical valves. I believe there are other blood thinners in the pipeline that might be used to - in place Coumadin some day, but right now Coumadin is the standard. Coumadin or Di-cumarol worldwide is a standard for use with the mechanical valves. John Puskas: Coumadin is the most common blood thinner used for mechanical valves. It's a very effective medicine, it prevents blood from clotting easily or normally, and giving in the right dose range, it will prevent blood from clotting on chemical valves quite reliably, but not perfectly. And of course if one takes too much of it we have bleeding problems. So we are always balancing the risk of too much Coumadin, which causes bleeding complications, nose bleeds, hemorrhoidal bleeding, bleeding around the gums, ulcers, for instance. On the one hand taking too much, but if you take too little, you have risk for clots forming
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