Valvular Disease
By Dr. Kent Niss
The last week of Heart Health month doesn’t mean that we need to stop thinking about heart health for the other months of the year, but it is a fitting time to discuss one more important topic when it comes to diseases that affect the heart. We have gone over a lot of risk factors and even some of the most common disease processes but today let’s venture into the topic of diseases of the valves of the heart. Whenever your provider listens to your heart they are primarily listening to these valves and the sounds they make. I’d like to go over the valves that are in our heart and then the two valves that most commonly begin to have issues.
A short anatomy lesson. As I said when we listen to your heart it is to illicit a lot of information, but most directly we are listening to the movement of the valves or more precisely the closing of the valves. The heart makes a typical “lub dub” sound when listened to closely. This is the closing of the valves in two different sets. Anything that disturbs the closing or opening of those valves or causes turbulent flow of blood across those values results in a murmur. Murmurs are usually thought of as a bad or concerning marker, but some can be completely innocent and have no consequence. We have four valves in our heart, and they open and close in sets of two. These valves do exactly what any other valve you may have seen does and they allow the blood to flow in one direction and one direction only as to prevent backflow of blood. The arteries are named as follows (in order of blood flow): the tricuspid valve, the pulmonic valve, the mitral valve and the aortic valve. The two valves that most typically lead to disease burden are the aortic valve and the mitral valve.
There are many things that can lead to damage to the valves of the heart. Simple “wear and tear” is the most common. However, I shouldn’t call it “simple”; this is wear and tear that occurs in the heart of those with risk factors we have talked about before: smoking, obesity, high blood pressure, uncontrolled diabetes, family history and high cholesterol. However, there are many other things that can lead to damage and dysfunction of these valves, such as infections (called endocarditis), rheumatic fever (most common cause worldwide but very rare in the United States because of effective antibiotic use), congestive heart failure or even that the valve wasn’t formed right when you were developing as an embryo. Valves have dysfunction in two main ways: regurgitation (backflow) and/or stenosis (hardening/stiffening).
Aortic stenosis (AS) is one of the most common forms of valvular disease. This is when the aortic valve (the last valve before blood exits the heart and goes to the rest of the body) becomes stiff or rigid. This leads to the valve not only opening slowly but also closing slowly or not completely. This can cause decreased or more commonly turbulent blood flow out of the heart. In some more rare circumstances this is caused by a malformed aortic valve. Typical symptoms of this can be high blood pressure, dizziness particularly when trying to do activity, sometimes passing out or extreme lightheadedness, but is most commonly first noticed with the stethoscope at a regular doctor’s appointment. Hearing the typical murmur associated with a stenotic aortic valve is the most common way of identifying that this stenosis is present.
Mitral valve regurgitation (MVR) is a very near second when it comes to valvular disease. This is most commonly caused by diseases such as high blood pressure, past heart attacks, obstructive sleep apnea and some autoimmune diseases. This is the valve that sits between the lungs (newly oxygenated blood) and the last chamber of the heart (the left ventricle). So, there is quite a bit of physical pressure here and all of the conditions noted above increase the pressure and strain in this area. Regurgitation or back flow happens at this valve then in turn increases the pressure in the blood vessels in the lungs. The downstream effects of this are numerous: hypertension in the vessels in the lungs can lead to fluid building up around the lungs, back pressure on the previous chambers of the heart can cause them to function more inefficiently which can then lead to swelling in the lower extremities, called edema. This is one of the primary factors that leads to congestive heart failure. Again, the most common way of identifying this dysfunction is with the stethoscope. That instrument that was invented over 200 years ago continues to be one of the most effective tools for the medical provider. However, common symptoms of MVR are shortness of breath (particularly when exerting oneself), swelling in the legs/feet or increased fatigue with activity.
There has been a lot of progress with the management of valvular diseases over the years and in recent years huge strides have been made that have led to the procedures to fix valves to become much less of a risk. The first step in managing valvular disorders once they are noticed is to establish what the problem is and to what degree of dysfunction there is. This is determined by an echocardiogram, an ultrasound of the heart. After this, focus is made on treating the underlying cause more aggressively: hypertension, diabetes, high cholesterol, coronary artery disease, obstructive sleep apnea, autoimmune conditions and infections. After this has had maximal effort, but progression of the valve’s dysfunction continues, or the severity was significant initially a discussion with a cardiologist or a cardiothoracic surgeon will take place. These valves can be repaired or even replaced! Which is an amazing feat! In the past this was done with open heart surgery and for some cases still is. However, the vast majority of these are now performed intra-arterially (through the arteries). The cardiologist will essentially use a large IV only inserted into an artery and then with a lot of skill is able to replace the valve through this method. This has become a very successful, minimally invasive and lower risk way of repairing/replacing these valves. There are some more steps and medications needed after this, but people do remarkably well!
The valves of our hearts are incredibly important and need some love and attention. Preventing these issues is by far the best option and can be done by taking the heart health steps we have talked about before. If you want to know more about valvular disease or want to discuss ways of preventing it, please reach out to your medical provider and they can help you with a good evidence-based approach.
