Muscular Dystrophy Breakthroughs -- In-Depth Doctor's Interview

What is a broad definition of muscular dystrophy?

Dr. Linda Cripe: Muscular dystrophy is a broad term that includes many different diseases. One of the diseases that is most common of the muscular dystrophies is Duchenne muscular dystrophy. That is a disease where an essential protein that helps the cell do its job is missing. That protein is called dystrophin. It affects one in every 3,000 to 3,500 boys, so it’s very common and prevalent in the population.

Does it only affect boys?

Dr. Cripe:  It’s not exclusively in boys, but the majority of the cases are in boys.

How do you currently detect Duchenne?

Dr. Cripe: Usually, it’s diagnosed after the child comes to the attention of the physician with symptoms of muscle weakness. The child may not be meeting their developmental milestone -- not walking on time, falling, tripping, unable to climb stairs -- and then after a diagnostic blood testing, the diagnosis is made.

Is there a common age when it’s detected?

Dr. Cripe: The most common age for it to be detected probably is between the ages of two and four, because that’s when you are doing a lot of developing in a gross motor way as a child

Are you working on ways that you detect the disease earlier so that you can start treatment earlier?

Dr. Cripe: I think that progress is being made. I think that we don’t have a real good way of detecting it earlier at this point in time, other than when the child is failing to meet their developmental milestones, though there is a movement afoot to try to develop newborn screening programs in some states. That would allow the blood testing to occur at a very early age.

Why is it important to get that diagnosis at an early stage?

Dr. Cripe: It’s important to make the diagnosis early because the only way that we have to treat this disease at this moment in time is by jumping on the symptoms as soon as possible and addressing them early in order to try to maximize the patient’s quality and quantity of life.

How do you, as a cardiologist, fit into this equation?

Dr. Cripe: It’s a disease of muscle, and heart is a muscle, too, so the heart muscle disease is a very important component of muscular dystrophy, specifically Duchenne muscular dystrophy. The heart muscle is affected in this disease. As the children age, it becomes much more clinically important to the individual as the heart muscle starts to fail, so we are very intimately involved in the care and treatment of children with Duchenne muscular dystrophy.

Is that ultimately the cause of death for these kids, the failure of the heart?

Dr. Cripe: The majority of the children will die as a result of either respiratory complication -- because it affects the muscles that help the child breathe -- or they will die as a result of the failure of the heart muscle to perform adequately.

On average, are these kids currently living longer?

Dr. Cripe: Yes, and I think that they’re living longer because we’re much better at keeping the house clean, so to speak. We’re much better at tending to the pulmonary complications of the disease, the heart muscle complications, and the skeletal muscle complications, but we don’t have a cure yet.

What is the average life span for patients?

Dr. Cripe: Traditionally, it’s thought that these young men will die in their late teens and early 20’s, and we’re really trying to push that margin back. I think that the majority of kids are living several years longer than they had because we’re being very attentive to making sure that the respiratory and cardiac function is optimized.

Have you seen Duchenne kids live longer lately?

Dr. Cripe: I think we have. In the past five or six years that I’ve been working with Duchenne kids exclusively here at Cincinnati Children’s Hospital, we have seen a dramatic change in the number of individuals who are living longer. They’re living into their mid-20’s, and I think we’re very proud of that.

How does an MRI help you detect heart disease earlier?

Dr. Cripe: One of the things that we’re pioneering here is we’re trying to find ways to evaluate the heart earlier in the disease process so that we can pick up those changes that we know are occurring in the heart earlier. One of the ways that we’re doing that is utilizing cardiac MRI. That allows us to see parts of the heart in ways that we haven’t seen before.

What could you see that would cause you to change a patient’s treatment?

Dr. Cripe: Previously, we were using a cardiac ultrasound to look at the heart, and by the time that you see changes in the cardiac ultrasound, with regards to how the heart is not functioning as well as it should, it’s very late in the disease process. By utilizing cardiac MRI, we’re able to see the development of the scar tissue forming in the heart muscle. As a result of that, we can institute traditional heart failure treatments earlier.

What types of heart failure treatments do you use?

Dr. Cripe: I wish that we could say that we had a magic bullet or a magical therapy that would erase this disease, or that we could eliminate this disease. Currently, the only tools that we have are very traditional methods to help a heart that is sick, but we can institute those therapies sooner than we normally would.
We would use ace inhibitors, beta blocker therapy -- sort of traditional heart failure treatments.

The hope is always a cure, but right now, are you focusing on just trying to give these patients a better quality of life?

Dr. Cripe: I think there are many, many scientists around the world that are desperately looking for a cure for this devastating illness, and that’s been going on for years. It’s a big disease and it’s been very elusive. Until those bench researchers find a cure, we’re left, as clinicians, to try to keep the kids’ quality and quantity of life maximized so that when the cure becomes available, the kids are healthy enough to take advantage of those therapies.

What is the status of your patient, Cameron?

Dr. Cripe: I think Cameron has been an inspiration to all of us here. Cameron’s will and desire and personality are such that he is an absolute inspiration to us. When he first came to the cardiology clinic, he had just finished high school and had dreams of going on to college and becoming a lawyer someday, and I think all of us really wondered whether he was going to be able to accomplish that goal from a health standpoint.  I think we all knew that he had that potential in him, because you can see that when you meet him. It’s thrilling to have watched him really push hard to reach that goal.

What types of treatments are next for Duchenne patients?

Dr. Cripe: It’s an interesting question. I don’t know where the cure is going to come from. There are a lot of different people working on a lot of different types of therapies, and sometimes in medicine the cure comes out of left field from somebody who is working in an ancillary field, even. As of this moment in time, I don’t think there’s any horse leading the pack, but there are a lot of horses running the race. I think all of us who take care of these boys just wish the scientists well for finding a speedy, speedy cure, because there are a lot of kids who really are in desperate need.

Does a patient’s attitude play a role in how much they can take on in life, such as going to college?

Dr. Cripe: I think the magic word is attitude. I think that when you are facing an obstacle, as large as Duchenne muscular dystrophy, the only weapon that you have is a positive attitude, and I think that Cameron epitomizes the word positive. He has always believed that he can and that comes through when you meet him instantly. It is truly an inspiration to all of us in the clinic who see him periodically when he comes in for his health care, how positive he is, and I think that’s led him to be very successful.

Do you believe that attitude can beat medicine?

Dr. Cripe: I think that attitude is what it’s all about. When we see the number of kids that we do here in this clinic -- the ones that are successful and the ones that are struggling -- I think that the difference between the two groups is attitude. I think the power of positive thinking, as they say, trumps all.

Does Cameron have to come to the clinic to take his heart failure medicine?

Dr. Cripe: We’re employing some unique heart failure therapies in Cameron in order to allow him to remain at home and to have him go to college and go to his classes. We have him on a medicine used for people with end-stage heart failure, typically in the intensive care unit. We have a small pump attached to his wheelchair and a very small plastic catheter inserted into his arm where that medicine could be continuously delivered 24 hours a day, seven days a week. That medicine has helped optimize his heart functions, so he is able to return to all of his daily activities.

What kind of medicine is he taking?

Dr. Cripe: The medicine is called milrinone, and it’s a medicine that helps the heart work a little bit more efficiently -- it helps the heart squeeze a little bit better by helping the blood vessels in the body relax. It allows the heart, as a pump, to relax as well. It’s similar to many of the oral medications that we use to treat heart failure, but it’s a medicine that is delivered intravenously. It’s a medicine that traditionally is reserved for patients who are in an intensive care setting.

END OF INTERVIEW

This information is intended for additional research purposes only. It is not to be used as a prescription or advice from Ivanhoe Broadcast News, Inc. or any medical professional interviewed. Ivanhoe Broadcast News, Inc. assumes no responsibility for the depth or accuracy of physician statements. Procedures or medicines apply to different people and medical factors; always consult your physician on medical matters.

If you would like more information, please contact:

Dr. Linda Cripe

Linda.cripe@cchmc.org

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