{"294921":{"#nid":"294921","#data":{"type":"news","title":"When Engineering is the Best Medicine","body":[{"value":"\u003Cp\u003E\u003Cstrong\u003EAjit Yoganathan\u2019s pioneering work makes people\u2019s hearts work better every day.\u003C\/strong\u003E\u003Cbr \/\u003E\u003Cbr \/\u003EDr. Kirk Kanter used to correct heart defects in the youngest children the way every other pediatric heart surgeon did. He\u2019d enter the operating room, open the infant\u2019s chest, look at the shape of the heart, and then \u2014 based on what he was seeing for the first time \u2014 make an on-the-spot judgment about the best surgical option.\u003C\/p\u003E\u003Cp\u003ENot anymore. While most surgeons still have to make last-minute decisions about rebuilding a heart that didn\u2019t fully develop, Kanter knows what he\u2019s going to do before he walks through the operating room door.\u003C\/p\u003E\u003Cp\u003EKanter figures it out ahead of time by using software conceptualized by Ajit Yoganathan, Regents\u2019 Professor in the Wallace H. Coulter Department of Biomedical Engineering. Yoganathan is a leading researcher in cardiovascular fluid mechanics, the study of how blood flows through the heart, and it\u2019s his expertise that clues Kanter in to the best surgical choice.\u003C\/p\u003E\u003Cp\u003EWhere some researchers are satisfied with making contributions to the body of scientific knowledge, Yoganathan is focused on translational research \u2014 or as he puts it, \u201cgetting things out of the lab from our research to impact healthcare and patients.\u201d He is the department\u2019s associate chair for translational research (a term scientists use for moving findings from the lab into clinical settings), and his dedication to developing real-world applications has made him a hero in the cardiovascular field.\u003C\/p\u003E\u003Cp\u003EImproving patient care and patients\u2019 lives is what drives Yoganathan. In delivering a 2012 lecture to the Biomedical Engineering Society, which honored him with its Pritzker Award, he said, \u201cI think the main goal should be not the commercialization to make money as a faculty member, but to have the satisfaction of being able to see your research translated in the clinic towards helping human health.\u201d\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EExamining the tiniest hearts\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EThe pediatric cardiac surgical planning tool that Kanter uses is one such practical application of Yoganathan\u2019s work in fluid mechanics. Kanter uses the tool to help patients whose hearts have only one ventricle. Although such cases are rare \u2013 two children per thousand births \u2013 the prospects for babies with single ventricle malformations are grim: Their hearts can\u2019t circulate blood through the lungs to be loaded with oxygen and on to the body. The lack of oxygen leads to rapid organ failure and even brain damage.\u003C\/p\u003E\u003Cp\u003EToday, the outlook for single ventricle patients is better. Prenatal care often reveals the defect before birth, so surgeons are prepared to take immediate action. Doctors reroute the body\u2019s main veins directly into the lungs, bypassing the heart. The blood picks up needed oxygen, then flows from the lungs into the heart\u2019s single ventricle, which pumps it out to the body. To achieve success, surgeons must perform two or three surgeries in the patient\u2019s first three years of life, including the final operation that connects the veins to the lungs.\u003C\/p\u003E\u003Cp\u003EIt\u2019s in preparation for this last operation, known as Fontan surgery, that Kanter uses Yoganathan\u2019s surgical planning tool. On his laptop, Kanter views a three-dimensional image of the patient\u2019s heart. The image has been created using MRI tomography, a series of magnetic scans compiled to show the heart\u2019s exact shape. Interactive features of the surgical planning tool, developed by Professor Jarek Rossignac in Georgia Tech\u2019s College of Computing, allow Kanter to turn the image and examine the heart from different angles. Then, based on his surgical experience, the doctor inputs several possible surgical corrections.\u003C\/p\u003E\u003Cp\u003EThe virtual surgery software has an undeniable coolness factor, but the computation and analysis done in Yoganathan\u2019s lab makes the real difference. It\u2019s there that researchers evaluate each option, using complex formulas to figure out how the blood would flow to each lung after the correction.\u003C\/p\u003E\u003Cp\u003EYoganathan never advises the surgeon on which option to choose. Instead, he sends images for each surgical scenario, showing his prediction of blood flow through the lungs and heart. Then the surgeon makes the decision based on priorities for the specific patient.\u003C\/p\u003E\u003Cp\u003EKanter says he typically has Yoganathan evaluate four to six options. Once he\u2019s seen the analysis, he can go into the surgery with high certainty he\u2019s choosing the best one.\u003C\/p\u003E\u003Cp\u003E\u201cSometimes it\u0027s what we think would have worked,\u201d he says, \u201cbut I\u0027m surprised at how often the best option is not the one I expected.\u201d\u003C\/p\u003E\u003Cp\u003ESo far, the surgical planning tool, called SURGEM, is used at only a few premier children\u2019s hospitals in the United States, including the Children\u2019s Hospital of Philadelphia and Children\u2019s Hospital of Atlanta at Egleston, where Kanter works as one of the leading pediatric cardiac surgeons in the nation.\u003C\/p\u003E\u003Cp\u003E\u201cWe have people from all over the country contacting us and trying to do simulations for them so we can get the best operations,\u201d says Kanter, who was one of the first surgeons to use the tool. \u201cThis is hot stuff.\u201d\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EFrom bench to bassinet\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003ESince Yoganathan arrived at Georgia Tech more than 30 years ago, he\u2019s made it his mission to use science as a means to the ultimate end for biomedicine: improving human health. He brought the translational mindset from the California Institute of Technology, where he completed his doctoral work under Professor William Cochran.\u003C\/p\u003E\u003Cp\u003E\u201cHe always said that engineering had a lot to offer towards medicine,\u201d Yoganathan recalls of his mentor. It was Cochran who first exposed Yoganathan to the field of cardiovascular fluid mechanics. Yoganathan, whose parents were a professor of pathology and a general practitioner, was hooked.\u003C\/p\u003E\u003Cp\u003EYoganathan uses the common phrase \u201cbench to bedside\u201d when talking about his work, occasionally giving it a twist. \u201cBench to bassinet,\u201d he says, noting his lab\u2019s impact on treating the heart conditions of infants.\u003C\/p\u003E\u003Cp\u003EHe insists that he doesn\u2019t set out to create new devices or change surgical methods. His goal is to understand the biomechanics of blood flow in the heart. But while he\u2019s doing the research, he sometimes gets a flash of insight about how to improve treatments \u2014 an inspiration that can turn into a major advance.\u003C\/p\u003E\u003Cp\u003EThat\u2019s what led to the development of a surgical technique called a Y graft, which Kanter has used in two dozen Fontan surgeries. Yoganathan dreamed up the technique while he was studying single ventricle cases, analyzing post-surgical blood flows. He saw that when blood from the upper body and lower body entered the lungs, it was colliding and mixing. That effect slowed its movement, making it harder for the blood to be pumped through the lungs.\u003C\/p\u003E\u003Cp\u003EHe wondered if grafting the veins in a Y-shape, instead of a straight graft, would help. Computer models gave credence to his idea. They showed the Y graft would make circulation more balanced and efficient. That would reduce the stress on the heart, which ideally would allow patients to live longer with less risk of heart failure \u2014 a common outcome that forces many single ventricle patients to undergo a heart transplant in their teens or early 20s, when their surgically repaired hearts give out.\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003EFinding the answers\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EYoganathan has seen his work translated to health care settings many times over. During decades of research on heart valves, he\u2019s worked with every manufacturer that has a replacement valve on the American market. He\u2019s also assisted the Food and Drug Administration in its regulation of cardiac devices.\u003C\/p\u003E\u003Cp\u003EThis exploration of valves is both vast and painstaking. Much of his lab\u2019s work is done with porcine or ovine heart valves, which closely match human physiology. Researchers modify the valves to mimic different types and stages of valve failure. Then, they use engineering tools and techniques to monitor the resulting changes in blood flow and mechanical stress. Finally, they make a surgical correction and see what effect it has.\u003C\/p\u003E\u003Cp\u003EYoganathan explains that his research aims to see how the valve\u2019s performance changes when its shape is changed by disease in the surrounding tissues or breakdowns of the valve itself. Then, investigators want to know how well various surgical corrections work to restore the valve\u2019s function. Finally, they try to figure out why some surgical repairs have a limited lifespan.\u003C\/p\u003E\u003Cp\u003E\u201cIt\u2019s really trying to understand why some of the surgical repairs eventually fail,\u201d he says.\u003C\/p\u003E\u003Cp\u003EThe research done in the lab is invaluable, because only in the lab can a scientist control all the variables. In clinical practice, the differences among patients\u2019 overall health makes it nearly impossible to isolate the problems with a particular surgery or device. In Yoganathan\u2019s lab, though, the conditions are consistent, so scientists can isolate the sources of breakdowns \u2013 as they did when they studied bileaflet valves, the most common type of mechanical prosthetic heart valve.\u003C\/p\u003E\u003Cp\u003EIn as many as 5 percent of patients, prosthetic valves lead to life-threatening blood clots. To reduce this risk, patients are prescribed anticoagulant drugs for the remainder of their lives; however, these medications can have serious long-term side effects. Yoganathan wanted to figure out what caused the clots in the first place.\u003C\/p\u003E\u003Cp\u003EHis research showed how some of the blood traveling through the artificial valve tended to stagnate around the valve hinges. Stagnant blood leads to clots. If the valve could be redesigned to get that blood flowing, it could minimize or alleviate the clots.\u003C\/p\u003E\u003Cp\u003EDevice manufacturers and surgeons pay careful attention to Yoganathan\u2019s work and adjust their practices accordingly. Likewise, Yoganathan listens to manufacturers and doctors and allows their practical needs to guide his research.\u003C\/p\u003E\u003Cp\u003EDon Giddens, Ph.D., the former dean of the College of Engineering who helped recruit Yoganathan, says Yoganathan has always taken a collaborative approach to working with clinicians, even when such approaches were rare. He believes Yoganathan always knew that working hand-in-hand with practicing doctors would lead to the greatest impact on health.\u003C\/p\u003E\u003Cp\u003E\u201cHis focus on translational research \u2013 that is, getting things to patients, and direct interaction with the clinical environment \u2013 was path-breaking,\u201d Giddens says.\u003C\/p\u003E\u003Cp\u003EYoganathan\u2019s influence has also shaped teaching at Georgia Tech, Giddens notes. Yoganathan spurred the creation of the master\u2019s and Ph.D. degrees in bioengineering, and he was a leader in the effort to establish the Coulter Department of Biomedical Engineering.\u003C\/p\u003E\u003Cp\u003EBeyond that is Yoganathan\u2019s impact on the future of biomechanical engineering by mentoring the engineers of the future. Over the years, more than 100 graduate students and post-doctoral fellows have trained and worked in Yoganathan\u2019s lab. One former student, research engineer Jorge Jimenez, Ph.D., says Yoganathan passes on to them his passion for improving lives through biomedical engineering.\u003C\/p\u003E\u003Cp\u003E\u201cThe scientist is a very serious person, really driven,\u201d Jimenez says in describing Yoganathan, \u201cbut if you talk to him personally, you see that he also cares a lot\u201d about the patients he\u2019s helping.\u003C\/p\u003E\u003Cp\u003EJimenez became a full-time member of Yoganathan\u2019s research faculty in 2007 and now divides his time between working in the lab and leading Apica Cardiovascular, a commercial venture launched in 2009 based on research done in the lab. Apica is testing a device that would change heart valve replacement from an open-heart surgery to a minimally invasive procedure. The device can be inserted into the left ventricle of the heart without opening the whole chest. It can implant a replacement heart valve, then close the incision in the heart with minimal blood loss, alleviating the need to use a heart bypass machine.\u003C\/p\u003E\u003Cp\u003EThat kind of radical shift in cardiovascular repair would only add to Yoganathan\u2019s already stellar reputation. Yet as much as he has accomplished during his career, and as proud as he is of how his research has set new standards for cardiovascular care, Yoganathan\u2019s pride in his own work is tempered by his reverence for the inherent design of the heart.\u003C\/p\u003E\u003Cp\u003E\u201cNo matter what, the human body and the heart are very well designed \u2014 from an engineering point of view,\u201d he says. \u201cIt has built-in safety factors. Even when there are small problems, the [heart] valve works fine. It takes a lot before that valve begins to fail and create significant medical problems... It\u2019s a marvel.\u201d\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":[{"value":"Ajit Yoganathan\u2019s pioneering work makes people\u2019s hearts work better every day"}],"field_summary":[{"value":"\u003Cp\u003EAjit Yoganathan\u2019s pioneering work makes people\u2019s hearts work better every day\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Ajit Yoganathan\u2019s pioneering work makes people\u2019s hearts work better every day"}],"uid":"27195","created_gmt":"2014-05-05 08:50:00","changed_gmt":"2016-10-08 03:16:22","author":"Colly Mitchell","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2014-05-05T00:00:00-04:00","iso_date":"2014-05-05T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"294911":{"id":"294911","type":"image","title":"Ajit Yoganathan, PhD - Regents\u0027 Professor, Wallace H. Coulter Department of Biomedical Engineering","body":null,"created":"1449244514","gmt_created":"2015-12-04 15:55:14","changed":"1475894993","gmt_changed":"2016-10-08 02:49:53","alt":"Ajit Yoganathan, PhD - Regents\u0027 Professor, Wallace H. Coulter Department of Biomedical Engineering","file":{"fid":"199363","name":"yoganathanajit-may2014.jpg","image_path":"\/sites\/default\/files\/images\/yoganathanajit-may2014_0.jpg","image_full_path":"http:\/\/www.tlwarc.hg.gatech.edu\/\/sites\/default\/files\/images\/yoganathanajit-may2014_0.jpg","mime":"image\/jpeg","size":3981332,"path_740":"http:\/\/www.tlwarc.hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/images\/yoganathanajit-may2014_0.jpg?itok=2tE82GK9"}}},"media_ids":["294911"],"related_links":[{"url":"http:\/\/groups.bme.gatech.edu\/groups\/cfmg\/group\/home.htm","title":"Yoganathan lab"}],"groups":[{"id":"1292","name":"Parker H. Petit Institute for Bioengineering and Bioscience (IBB)"}],"categories":[{"id":"132","name":"Institute Leadership"},{"id":"134","name":"Student and Faculty"}],"keywords":[],"core_research_areas":[{"id":"39441","name":"Bioengineering and Bioscience"}],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EDori Kleber, writer\u003Cbr \/\u003E\u003Ca href=\u0022mailto:kay.kinard@coe.gatech.edu\u0022\u003EKay Kinard\u003Cbr \/\u003E\u003C\/a\u003EDirector of Communcations, College of Engineering\u003C\/p\u003E","format":"limited_html"}],"email":["kay.kinard@coe.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}