The ability to operate inside the heart on small valves – tissue flaps that keep blood flowing in the correct direction – is an amazing medical development that returns the quality of life to thousands of patients.
Equally amazing are the developments in technology and technique that have improved outcomes and the life of repaired or replaced heart valves, as explained by McLeod Cardiothoracic Surgeon Michael Carmichael, MD:
Here’s a summary of Dr. Carmichael’s comments:
There’s been steady progress in surgery for heart valves. For years, we used a replacement valve from a pig’s heart, but the expectation was in 8 to 10 years the pig’s heart was in need of replacement.
Now we are predominantly using the Bovine Pericardial Valve, which is actually made from the tissue sack (pericardium) surrounding a cow’s heart. These endure upwards to 30 years in the mitral valve, one of four valves in the heart. In the atrial valve, they endure up to twenty years due to the durability of the tissue and the pre-treatment used to prevent the tissue from deteriorating.
A new technique for valve replacement that many may have heard of is the TAVR – Transcatheter Arterial Valvular Replacement. With TAVR, you don’t have to have open-heart surgery, where the chest is open either through the sternum or through the ribs.
We enter through the femoral artery, up into the aorta. (See illustration in the video.) TAVR is reserved for patients that are extremely high risk for having surgery. This is only for the Atrial Valve. A transcatheter procedure for the mitral valve is not done in this country, except in very limited experimental conditions.
The transcatheter aortic replacement was released by the FDA several years ago, but it’s been done in Europe for probably a decade.
In addition to tissue valves, mechanical valves are also available. The major advantage to the mechanical valve is that it will never wear out. It’s just below the hardness of the diamond. (See illustration in the video.) It’s made up of a material called pyrolytic carbon. With a mechanical valve you have a mechanical structure in the bloodstream; therefore, you have to take blood thinners the rest your life.
Part of the decision to use tissue valve versus mechanical is based upon the age the patient. For the younger patient, we are going to lean more towards a mechanical valve so that they won’t have to have a repeat operation later in life
There other factors that go into this decision. Technical decisions that we make at the time a surgery include, “Is the patient going to need blood thinners anyway because of underlying medical conditions?” If they are, you might as well select a mechanical valve because it will last indefinitely.
The first step in correcting heart valve problems is seeing a cardiologist, who will help diagnose the problem and, if needed, refer you to a cardiothoracic surgeon.