Lung coils for Emphysema
BACKGROUND: Emphysema occurs when air sacs in the lungs are destroyed gradually, which will make a patient progressively short of breath. It is one of the many diseases known collectively as chronic obstructive pulmonary disease (COPD). As emphysema worsens, it turns the spherical air sacs, which look like a cluster of grapes, into large pockets with gaping holes in their inner walls. This results in the reduction of the surface area of the lungs and the amount of oxygen that reaches the bloodstream. The elastic fibers that open the small airways leading to the air sacs slowly get destroyed as well. (Source: www.mayoclinic.com)
SIGNS: A patient can have emphysema for years without knowing it. Shortness of breath will begin gradually. Then, patients may start avoiding activities that can cause them to get winded. Eventually, emphysema will cause shortness of breath even while resting. Immediate medical attention is needed if a patient is so short of breath that they can't speak, their lips or fingernails turn gray or blue, their heartbeat is usually fast, or if they're not mentally alert. Smoking is the leading cause of emphysema and treatment can only slow the progression, not reverse the damage. Long-term exposure to airborne irritants, including tobacco smoke, marijuana smoke, air pollution, coal and silica dust, or manufacturing fumes, can cause emphysema too. (Source: www.mayoclinic.com)
TREATMENT: The first step for patients with emphysema would be to quit smoking. Smoking cessation drugs, bupropion hydrochloride (Zyban) or varenicline (Chantix), can help. Bronchodilators, inhaled steroids, and antibiotics can also help treat emphysema. Therapies, like pulmonary rehabilitation and supplemental oxygen, can help as well. In severe cases, the doctor might recommend a lung transplant or lung volume reduction surgery. (Source: www.mayoclinic.com)
NEW TECHNOLOGY: Researchers at the University of Pittsburgh Medical Center (UPMC) is the first center in North America to enroll patients into an FDA approved clinical trial that will test whether the insertion of small coils can collapse the diseased lung areas and improve lung function, along with exercise tolerance among patients with advanced emphysema. The study aims to recruit 315 patients in 30 different U.S. and European centers. The RENEW Lung Volume Reduction Coils provide a minimally invasive alternative to lung volume reduction surgery. European pulmonologists have been investigating the device for four years, but researchers at UPMC believe that only a large, randomized trial can medically prove the device's effectiveness. The coils are small, elastic, shape-memory coils that are made of a metal that is commonly used in medical implants. Researchers implanted up to 10 coils in wire form into the lung of one patient. After deployment the wires recoil, pulling in the damaged lung area so that the remaining, healthy lung can inflate and deflate more effectively while improving airway function and breathing both at rest and during exercise. (Source: http://www.upmc.com/media/NewsReleases/2013/Pages/Patients-Trial-Coils-Emphysema-Lungs.aspx) For study information contact: Christine Ledezma, UPMC Clinical Research Coordinator (412) 864-3368.
Dr. Frank Sciurba, Director of COPD/Emphysema Research Center at the University of Pittsburgh Medical Center (UPMC), discusses how lung coils are helping emphysema patients.
Can you describe what emphysema is and what it does to the body?
Dr. Sciurba: Emphysema is a disease in this country and at least 80% of cases are tobacco related, although in the third world, indoor cooking is also a common cause, especially in women. Many folks have heard about COPD lately. Emphysema is a subtype of COPD, but it's often present to varying amounts in all patients that have COPD. Emphysema is the destruction of the walls between the grape-like clusters of air sacs, known as alveoli. So, these tiny grape-like clusters coalesce to form larger and larger grapes, which are eventually forming holes in the lung. This has two consequences. One is the lung acts like it's over-stretched so it doesn't have the spring back that helps you breathe. The other consequence is that we lose the tethering of the airway so on exhalation the airways collapse. The consequence of this is that patients not only can't breathe out forcefully, but they can't breathe their air out as completely. So, they trap air and become hyper inflated. A very understandable way I like to explain this to students or family: First breathe to the top of your lungs, now Instead of exhaling to your normal relaxed expiatory state like you and I normally do breathe out just a teacup of air. Now breathe back in and out just that teacup at the top of your lungs, and if you do that you sense what it is to be hyper-inflated and feel that uncomfortable extra work of breathing way up there. That's what we're trying to deal with in these patients; we're trying to deflate them, allow them to exhale more completely.
Is there a cure for emphysema?
Dr. Sciurba: Right now by stopping smoking we can dramatically slow the process of progression, but we don't have any therapies that can really completely reverse the damage.
What is the best procedure for a patient with emphysema? How do they get relief?
Dr. Sciurba: Because we're limited in what medications can do, there's a history of trying to develop more heroic therapies. Of course, lung transplantation in the right patient can dramatically improve quality of life, but there's a lot that goes with that. About fifteen years ago a procedure was developed, and University of Pittsburgh played a large role in that, called lung volume reduction surgery, which is where we resect the worst areas of the lung allowing the better portions of the lung to expand within the chest and stretch out so they work more effectively. The remaining lung has more recoil, more elasticity, and patients are able to breathe out more forcefully and completely. However, this is also major surgery in people with advanced lung disease, and so companies and researchers in our field have been trying to develop less invasive approaches to do the same thing. A couple of years ago, we published a study using endobronchial valves, which allow the patients' worst areas of the lung to collapse, again allowing the better areas to fill the space created. This worked in some patients, but there were issues involved with their effectiveness because the lobes are connected; we call that collateral ventilation. The lobe that we didn't put the valves in would continue to supply or leak air into the lobes that did have the valves in, and this limited the effectiveness. So a company, PneumRx, came up with a strategy that was independent of this collateral ventilation. This is a therapy that we're currently evaluating: putting coils into the lung to compress the worst areas of the lung, allowing better areas to expand which then allows stretching of the uncompressed lung so that it can spring back more effectively and allow it to tether those airways so people can breathe more forcefully and more completely. Decreasing that lung hyperinflation leads downstream to improving exercise tolerance activity and quality of life, which is what we hope to achieve in these patients.
Tell me a little bit about the coils. How big are they and what are they made of?
Dr. Sciurba: The coils are made of a material commonly used in medical implants called nitinol; it's a metal. The nitinol coils go in the lungs as straight wires and then they fold up like a baseball seam. They fold in half, then they fold in half again, and as they do that they bring in the lung. The coils are between ten and fifteen centimeters long and they're relatively small after they fold up. The way PneumRx has designed the protocol, ten coils are put in to one lung and the patient comes back four months later, then ten coils are put in the other lung.
Are these permanent implants then?
Dr. Sciurba: While in the short run we know that they can be removed, in the long run that's not known. So, we do consider them to be permanent implants.
This is considered minimally invasive surgery then?
Dr. Sciurba: Yes, because there's no cutting and the short-term side effects are expected to be minimal relative to lung volume reduction surgery for instance. So the short-term consequences are minimal and it doesn't have the recovery time that we expect with a surgical procedure.
What's the benefit to patients and which patients would most benefit from this procedure?
Dr. Sciurba: We're looking for patients with advanced COPD who are beginning to have limitations in their activity. We're not going to be doing it on patients with early disease, rather patients who really have hyperinflation and your lung doctor or internist would be able to measure your lung function to confirm this. So, we're looking for patients with significant hyperinflation and severe COPD.
The woman we talked to, Linda, said she immediately felt the difference. Is that expected?
Dr. Sciurba: I hope it's real but the reality is we do these clinical trials because something like this is going to have a potentially very strong placebo effect. I do believe that when I listen to her lungs I heard better breath sounds the next morning after the procedure on the right side compared to the left side where we didn't do the procedure, but physicians and researchers want to believe we're doing the right thing as well. That's why we're randomizing patients. The study is being sponsored by PneumRx, the company that invented these coils. It's going to be performed in thirty centers across Europe and North America. We're going to enroll about 315 patients and half will get the coils, half will get maximum medical therapy, and then we'll follow these patients for a year. At the end of a year we'll perform detailed lung function testing, exercise testing, questionnaires, and we'll be able to answer that question. While we're very optimistic with Linda's short-term response, we want to see how things last in the long run. This is a trial I'm real hopeful for because I really would like to have a tool that I can offer our more advanced patients and that's what we're looking for. So nothing would please me more than to find out Linda maintains her improvement and that this lasts a year.
So without this, what are the options for patients when they get to a difficult state?
Dr. Sciurba: Of course, transplantation is not an option for patients over 70 years old, which many of our patients are, so without these types of innovations our options are relatively limited with these patients. We really need to come up with something new, either drugs or devices, which is going to impact our patients with advanced disease.
It's a quality of life?
Dr. Sciurba: Quality of life is the ultimate thing. Patients don't care what their lung function is, what they care about is that they can exercise further, they can do more activity, and they have a better quality of life engaging with their family and enjoying life. That's what our goal is.
FOR MORE INFORMATION, PLEASE CONTACT:
Copyright 2013 by Ivanhoe Broadcast News. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.