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The Latest in Mitral Valve Treatment

Every year, nearly five million Americans learn they have heart valve disease. Awareness and early detection can save lives, so knowing the symptoms of the disease is important. At The Christ Hospital Health Network, we offer our patients the latest in aortic and mitral valve disease treatments not available elsewhere in our region. Our compassionate, highly trained aortic valve disease experts are improving our patients' quality and length of life. 

In this segment Mario Castillo-Sang, MD discusses aortic and mitral valve replacement and when to refer to a specialist.
The Latest in Mitral Valve Treatment
Featured Speaker:
Mario Castillo-Sang, MD
Cardiothoracic Surgeon, Mario Castillo Sang, MD, is an expert in minimally invasive aortic and mitral valve surgery with special interests including coronary revascularization, surgical management of atrial fibrillation and heart and lung transplantation. Dr. Castillo - Sang will play a pivotal role in the heart valve program at The Christ Hospital, which has pioneered minimally invasive valve replacement procedures and continues to introduce new treatments to our region.

Learn more about Mario Castillo-Sang, MD
Transcription:
The Latest in Mitral Valve Treatment

Melanie Cole (Host): Every year, nearly 5 million Americans learn they have heart valve disease. Awareness and early detection can save lives, so knowing the symptoms of the disease is important. My guest today, is Dr. Mario Castillo-Sang. He’s a cardiothoracic surgeon with the Christ Hospital Health Network. Welcome to the show, Dr. Castillo-Sang. Tell us a little bit about the evolution of valve disease and replacement as it’s happening.

Dr. Mario Castillo-Sang (Guest): Well, thank you for the invitation to speak with you. Valve disease – the mitral valve specifically is very common among the US population. Unfortunately, a good number of patients do develop symptoms from valve disease. One of the most common problems with the mitral valve – which is located on the left side of the heart – the heart has four chambers, two on the right and two on the left. This mitral valve separates the upper chamber from the lower chamber on the left side of the heart. This valve can actually leak, or it can be too tight. We call that regurgitation or stenosis respectively.

The mitral valve is supposed to work as a check valve allowing flow from the upper chamber of the heart into the lower chamber of the heart. Now, the blood that comes through the mitral valve comes from the lung, so it comes rich in oxygen. When the valve is too tight, the blood cannot flow downwards in the left ventricle -- the lower chamber in the heart -- and the pressure accumulates toward the lungs. That buildup of pressure will lead to symptoms of shortness of breath, fatigue. When the valve is leaking, the blood will go down unimpeded, but then it will bounce back into the upper chamber when the heart pumps, which it should not do. It’s supposed to be a one-way valve. That will lead to symptoms that are very similar, too – shortness of breath, fatigue, can’t lay flat.

All of these things lead, in time, to a deterioration of the chambers of the heart where the upper chamber will grow in size. In doing so, it can lead to something called atrial fibrillation. That’s an abnormal rhythm of the heart where the upper part does not coordinate well with the lower part of the heart. Atrial fibrillation can lead to stroke, and in time, mitral regurgitation can also lead to an enlargement of the left ventricle, the lower part of the left side of the heart. When that happens, the left side of the heart loses its power over time, and if you are with a normal heart at 60% -- which is totally normal – over time, you may find yourself having a 30 or 20% power, which will create – in addition to the symptoms of shortness of breath and fatigue – further problems downstream.

Melanie: How important is the early diagnosis as being crucial to improve outcome prediction, and what are some valuable prognostic tools to aid in early diagnosis of mitral valve disease?

Dr. Castillo-Sang: That is a very important question, and I'm glad you asked because as of 2014, the guidelines for mitral valve surgery have changed. In the past, to give you contrast, valve surgery was indicated only if patients were very symptomatic or if the damage to the bottom side of the left heart that I described to you had already occurred.

Today, it’s indicated to fix the mitral valve if the patient has severe mitral regurgitation even if they don’t have symptoms. The whole point is to prevent that structural damage to the heart that happens over time. We’re trying to catch the disease before the damage is done. So to speak, in the case of a diabetic, we’re trying to correct their sugars before they lose their toes, or they lose vision -- the end-organ damage is done.

With that, one of the things that's done is if somebody is known to have a mitral murmur or a murmur of the heart – which is something that your doctor or GP could listen to with a stethoscope. They should have an echocardiogram, and an echocardiogram will tell us which valve is affected – in this case, the mitral valve – and if it is affected is it because it's too tight or is it because it's leaking? If either of the two is severe --that is severe mitral stenosis or tightness, or severe mitral regurgitation or leakage of the valve – then that should lead to a referral to a cardiologist and/or a surgeon even if the patient is not symptomatic. The reason for that is that we will prevent, by treating it early, all the downstream effects of the enlarging of the upper and the lower chambers of the heart, and the loss of the function of the heat.

Melanie: Speak about patient selection criteria. What kind of patient would be a good candidate?

Dr. Castillo-Sang: Mitral valve disease does not choose patients, and frankly, we see it in all age groups. There are different categories of what causes the valve to be leaking or to be tight. For example, a mitral valve that’s too tight is often a secondary effect of having had rheumatic fever as a child, that is a simple strep throat that went untreated as a child, as an adult, can lead to a very tight valve. That needs a valve replacement that is one form of operation of the mitral valve.

Other forms of the mitral disease are degenerative mitral valve disease, that is patients who have leakage of the valve because the valve has suffered structural damage. To give you an analogy, a parachute and the canopy of a parachute is held down by the string. If you cut the string, the canopy will move sideways. The same for the mitral valve. The valve has two sides, and each one is held by strings attaching it to the lower part of the heart. If one of those strings gets cut or torn, the valve will fail, and you will have leakage. That's called degenerative mitral valve disease. In that circumstance, as the medical community, we do not know what causes this. We haven’t gotten to a gene or a form of inheritance of this, but it does happen quite commonly. It fact, it’s the most common form of degenerative mitral valve damage. When that is the case, that valve can often times be fixed – that is, repaired – and if that is not successful or not possible, then the valve can be replaced

There are two ways of approaching the mitral valve in terms of surgery. One is the conventional, standard approach which has been with us for the last 50 years, which is doing a median sternotomy – that is, opening the breastbone and performing the operation using the heart-lung machine, stopping the heart to open the heart and then opening the heart to look at the valve to repair it or replace it depending on what the patient needs.

The other new form – or newer form, I should say, because it’s been with us since 1998, yet it’s not widely adopted on the basis of the expertise in different centers, but the results are great. It’s a minimally invasive approach. The minimally invasive approach entails going through a different access other than the sternum. The sternum is not opened, and through the rib cage on the right side of the chest wall, we make a very small incision, about 3.5 centimeters. We also make a very small incision in the groin for the heart and lung machine to be connected to the patient. Once we are on bypass, we can just as easily open the heart and look at a valve and fix it or replace it, both in one sitting.

This newer approach allows patients a faster recovery. Patients traditionally would stay in the hospital between five and seven days after open-heart surgery. Sometimes patients were going home in three days after open-heart surgery. Their discomfort from the incision is minimal. At times, we have patients that don't take a narcotic for days after the operation, so that’s a significant improvement in the way we can approach the valve. Newer technologies are coming in, one of which is the Mitral Clip. I’m sure we’ll talk more about that in the future, but the Mitral Clip is an approach through the groin – through a vein – just like having an angiogram, but through a vein where we go through the groin and into the heart, and we pinch together the two edges of the leaflets of the mitral valve that are making it leak, and with that, decreasing the leakage. We do that at the Christ Hospital, and we're very successful at it. That is only approved for patients that are very, very high risk for open-heart surgery as it is right now, dictated by the FDA.

Other therapies are coming, and the Christ Hospital will be participating in these therapies, which implies replacing – not repairing, but replacing the mitral valve with catheter therapy. As it stands right now, the newer technologies will be done through the tip of the heart by making a very small incision on the left chest, and accessing the apex or the tip of the heart, and through that, putting in a very small catheter through which the valve will be deployed within the patients’ own mitral valve and will replace it – much like we do nowadays with TAVR, which is a Transcatheter Aortic valve Replacement but in this situation it would be for the mitral valve. That technology will be with us at the Christ Hospital in the way of research in the next three to four months.

Melanie: TCH is unique for having a comprehensive valve program, Doctor, and being a leader in research trials. Are there some other treatments or research that you would like to speak about at the Christ Hospital Health Network that other physicians may not be aware of?

Dr. Castillo-Sang: Sure. We are participating in multiple trials,as you mentioned. Some of which are dedicated exclusively to valves and the TAVR or the Transcatheter Aortic Valve Replacement field, we have been pioneering this – Dr. Dean Kereiakes, Dr.Sarembock, and Dr. Choo – have been pioneering this. One of the things we’re doing is a study looking at treating patients that have severe aortic valve stenosis – tightening of the aortic valve – before they become symptomatic. Another one is treating patients who are at low risk for surgical open-heart surgery. In those patients, we can randomize them, so either getting open-heart surgery or getting a transcatheter valve through the groin. These are two important research trials that we have ongoing as it is.

On the mitral valve aspect, for those patients who have a very, very low power of the heart, where their heart is very deteriorated for X, Y, or Z reasons, we have a trial ongoing, it’s called the COAPT trial. That is meant to evaluate those patients and see if applying a clip to the mitral valve in the setting of severe mitral leakage would help improve their quality of life and prolong their life. That's another research trial we’re doing.

And finally, we have other multiple trials, one of which comes to mind is essentially those patients who have atrial fibrillation – we touched on that a little bit ago – and how that atrial fibrillation can lead to risks of stroke. For those patients who cannot take blood thinners and have atrial fibrillation, we have access to something called the Atrial Clip, and we apply those to close the left atrial appendage from the outside of the heart without having to be on the heart-lung machine or without having to stop the heart. With that, we think we may improve the risk of having a stroke in patients who have atrial fibrillation and cannot take anticoagulants.

Melanie: In summary, Doctor, please tell other physicians what you’d like them to know about recognizing mitral valve disease and the need for replacement and when to refer to a specialist?

Dr. Castillo-Sang: I would like to reiterate the availability of the multiple therapies we have available for the mitral valve at Christ Hospital nowadays. We perhaps have the most prolific options for patients out there with mitral valve disease in general in the city. We have, on the one hand, for patients who are good candidates for surgery, we can repair or replace their valve depending on the circumstances through a median sternotomy – which is the conventional approach – or we can do it through a minimally invasive approach through the right mini-thoracotomy, obtaining excellent results for both repair and replacement.

We also have, for those who are not a good candidate for open-heart surgery, the Mitral Clip. We’re going down the road of patients who are obviously sicker, and we have options for them. For those patients who may not be amenable for a Mitral Clip, we will have availability for research of valves that can be implanted through catheters without open-heart surgery, without stopping the heart.

And ultimately, at the end of the spectrum – at the very end of the spectrum, the sickest of the sickest patients – those that have very low power of the heart and have very severe mitral regurgitation, who are almost at the end of the rope, so to speak, we have therapies for heart failure, which is called Left Ventricular Assist Device or LVAD. That device can be a life-saving measure and can improve the quality of life dramatically.

We have a complete fan of options for patients who have mitral valve disease. I would add to that that the guidelines have changed for those patients who have been recognized to have mitral valve regurgitation and yet, have no symptoms, that it is important to identify and treat it early before the onset of symptoms and before – more importantly – the onset of the damages that mitral regurgitation can cause within the heart. For those patients, who have been identified to have severe mitral regurgitation and have a normally functioning heart, it is important to address it at that moment before things get worse.

Melanie: Thank you, so much, Doctor, for being with us today. You're listening to Expert Insights, Physician Views, and News, with the Christ Hospital Health Network. To learn more about Dr. Mario Castillo-Sang, and all of the Christ Hospital Physicians, please visit TCHPConnect.org, that's TCHPConnect.org. This is Melanie Cole. Thanks, so much, for listening.