Surgeon Q&A: What Are 8 Important Facts About Calcified Heart Valves?
By Adam Pick on September 15, 2016
I’ll never forget when my cardiologist said to me, “Adam, The calcium on your valve is causing serious problems. Your valve is stenotic. You need a new valve.” In that moment, I was overwhelmed with emotions and… questions. Some of the questions were, “What do you mean calcium on the valve?” and “What is stenosis?” and “OMG! Do I really need heart surgery?”
Ten years after surgery, I’m thrilled to report that my aortic valve replacement is doing great. That said, I receive a lot of excellent questions from our community about heart valve calcification. So, I wanted to create a special post dedicated to this very important topic.
To get the latest research about heart valve calcification, I contacted two cardiac surgeons that specialize in heart valve therapy – Dr. Michael Borger from Columbia University Medical Center in New York City and Dr. Joseph Lamelas from Mount Sinai Medical Center in Miami, Florida.
1. What is a calcified heart valve?
Dr. Borger Says: A calcified heart valve is one in which a large amount of calcium has been deposited over many years. Heart valves are normally formed of leaflets that are thin and pliable. When a heart valve becomes calcified, the leaflets become stiff and the valve eventually becomes narrowed (“stenotic”). The stenotic heart valve in turn leads to increased resistance to blood flow and increased cardiac work.
2. How does a heart valve get calcified?
Dr. Lamelas Says: There are multiple reasons that valves calcify. One particular reason is attributed to the normal wear and tear of the heart valves because of the fact that the heart is the hardest working muscle in the body. In addition, there can be genetic reasons which include congenital valve abnormalities where the valve stiffens later in life. Other factors that contribute to calcification include smoking, diabetes, chronic kidney disease and elevated cholesterol and triglyceride levels. Most valves become calcified by atherosclerosis, which is a process that causes blockages in the arteries of the heart as well as the rest of the body.
Calcified Aortic Valve
An inflammation can occur on the heart valve that leads to a reaction in the blood stream which promotes calcification. Despite all these potential reasons, the exact mechanism causing heart valve calcification is still being investigated. Other causes of aortic valve calcification or valve stiffening include radiation exposure to the chest and rheumatic aortic valve disease.
3. Can each of the four heart valves get calcified?
Dr. Lamelas Says: The left sided heart valves (aortic and mitral) are usually the valves that calcify. The aortic valve, which is the main valve or the “front door of the heart”, regulates all of the blood that leaves the heart and is the valve that calcifies most frequently. It is very unusual for the right- sided heart valves (tricuspid and pulmonary) to calcify and it is not really clear why.
When the aortic valve calcifies, it affects both, the valve leaflets (doors) and the annulus (the ring on which the valve sits). When the mitral valve calcifies, it mainly affects the annulus (ring) but can also involve the leaflets. The most common disease that causes mitral valve calcification is rheumatic valve disease. This typically occurs when a streptococcal throat infection affects the valve during youth but will not become evident until adolescence or adulthood.
Calcified Mitral Valve
Dr. Borger Says: Calcium deposits are more commonly found in areas of turbulent blood flow, which is more commonly found at the aortic valve in its position between the left ventricle and the aorta. Bicuspid aortic valves (BAV) and other valve anomalies result in particularly turbulent blood flow, which is why these patients present with valve calcification at a much earlier age. BAV disease is the most common congenital cardiac anomaly, occurring in 1-2% of the general population.
4. How does a calcified heart valve impact patients?
Dr. Borger Says: Once the calcification and valve stenosis become severe, patients will develop increasing shortness of breath on exertion. Lightheadedness and chest pain are other common symptoms.
Dr. Lamelas Says: Patients that have had long standing calcification of the heart valves may also develop heart enlargement as well as a thickened heart muscle. Contrary to the skeletal muscle in the rest of our body, heart muscle enlargement or thickening will negatively affect the heart. All of these consequences will limit a patient’s quality of life as well as long term survival.
Dr. Borger Says: In rare circumstances, patients with severe valve stenosis may suffer from cardiac arrest or sudden death. The likelihood of this occurring, however, is very low in patients who have not yet developed symptoms. Such symptoms are usually quick to resolve after valve replacement surgery.
5. How are calcified heart valves treated?
Dr. Lamelas Says: A valve replacement is indicated in patients where the calcium on the valve progresses to the point where its function is impaired and ultimately causing symptoms. There are 2 broad categories of replacement valves – mechanical and bio-prosthetic. Mechanical heart valve replacements are usually made of a metal material. Bio-prosthetic heart valve replacements are made of animal tissue, either cow or pig.
Mechanical (left) and Bio-Prosthetic (right) Heart Valves
The heart valves can be replaced with a surgical approach which can be performed in the conventional manner by opening the sternum (breast bone) or by a minimally invasive approach through a small incision on the side of the chest. In both of these procedures, the heart chamber is opened and the diseased valve is completely removed and a new valve is implanted.
Another option now available in selected patients with aortic valve stenosis is a trans-catheter aortic valve replacement (TAVR). In these procedures, the valve is most commonly delivered into the patient’s diseased aortic valve through an artery in the leg or arm. The diseased valve is not removed and the patient does not need to be placed on the heart lung machine.
Transcatheter Aortic Valve Replacement
Dr. Borger Says: Older, high risk patients with aortic stenosis are currently treated with transcatheter aortic valve replacement (TAVR), a revolutionary procedure that is usually performed through the groin and without the use of cardiopulmonary bypass.
6. If a calcified valve is replaced, can it get calcified again?
Dr. Lamelas Says: Yes. Bio-prosthetic valves that are implanted in young patients as well as those on dialysis have a greater chance of calcifying earlier. The natural stress on the valve from wear and tear can also lead to calcification and degeneration of the artificial valve. No one really knows exactly why these valves calcify but 2 theories exist. One is related to the way that the valves are treated or preserved with a chemical called glutaraldehyde which attracts calcium. The other may be an immune reaction that the body has to the artificial animal valve. On the other hand, metal or mechanical valves do not calcify, but they can fail when the doors of the valve become impaired, limiting its opening and closing. This can occur when clots form on the valve or when a thick tissue growth (pannus) develops underneath the valve.
7. We’ve heard that some of the new heart valve replacement devices have “anti-calcification” technologies like the Linx AC from St. Jude Medical. Can you talk about those technologies? How do they prevent calcification?
Dr. Borger Says: Almost all of the current generation of biological valves have some form of anti-calcification treatment. Most of them, including Linx AC, work by preventing the binding of calcium molecules to fat molecules on the valve leaflets. Such anti-calcification treatments appear very effective in bench side and animal studies. However, long-term follow up of patients provides the best evidence of anti-calcification effectiveness. That is one of the reasons why academic cardiac surgery centers are so interested in carefully following patients over time.
Dr. Lamelas Says: The main goal of all bio-prosthetic valve manufacturers is to develop a valve that does not calcify. As I mentioned previously, a chemical called glutaraldehyde is used to treat these valves. This chemical helps sterilize the valve, decreases its immune reaction and helps make the valve more durable. Despite its benefits, glutaraldehyde does promote calcification of the valve. Many companies have been working on different ways to limit this process. The Linx technology is one of these. It consists of treating these artificial valves with chemicals that reduce the effect that the glutaraldehyde has on the formation of calcium as well as decreasing the amount of cholesterol and lipids that form on the valves.
8. Is there anything else you feel patients should know about calcified heart valves? Any tips for preventing heart valve calcification?
Dr. Borger Says: This is a frequent question of patients, “What can patients do to prevent heart valve calcification?” Unfortunately, there is no known method by which someone can slow the calcification process in his or her heart valves. Once the problem is diagnosed, however, regular follow up with a cardiologist is recommended. In addition, referral to a surgeon should be done promptly in patients who develop symptoms of shortness of breath, chest pain, or lightheadedness.
Dr. Lamelas Says: A patient that has calcium on a heart valve should be followed carefully by their cardiologist. They should undergo echocardiograms (heart ultrasounds) on a yearly or even 6 month interval. If they develop symptoms, the echocardiogram should be performed sooner. Careful follow up and subsequent timely treatment when necessary, will allow for the lowest risks with any intervention, whether it be a surgical or transcatheter replacement. An educated patient living a healthy lifestyle will always have the best quality of life.
I hope that helped you learn more about heart valve calcification. I know it helped me. On behalf our community, I’d like to extend a humongous “Thank You!!!!” to Drs. Borger and Dr. Lamelas for sharing their clinical experiences and research with our community on this very special topic.
- See Dr. Borger’s Interactive Surgeon Profile
- Learn more about Dr. Lamelas
- Discover how the Linx AC Technology Resists Calcification
Keep on tickin!