July/August 2009 By Julie Budnik It has been a big year for Yasir Yesuf and his family. Yasir, a native of Ethiopia, just celebrated his first birthday thanks in large part to the extremely dedicated and talented medical professionals at Children's Healthcare of Atlanta (CHOA). In December of 2008, Yasir became the first pediatric patient in the state of Georgia to receive the EXCOR Pediatric ventricular assist device, better known as the Berlin Heart. In the past, families of infants and children who were critically ill with debilitating cardiac problems and awaiting transplantation had very few treatment options. The best physicians could hope for was to keep their patients managed with medications or place them on extracorporeal membrane oxygenation (ECMO) and hope that a donor heart would become available sooner rather than later. Unfortunately, many children continued to deteriorate and by the time a heart became available, they were often too ill with multiple organ failure to have a successful outcome. Pediatric cardiologists and surgeons now have a lifeline to offer these children that is very promising in terms of keeping these kids healthy enough to have a fighting chance at a good transplantation outcome - the Berlin Heart. The EXCOR Pediatric ventricular assist device is manufactured by Berlin Heart. The European-based company provides a variety of ventricular assist devices (VDAs) for use in the adult population and the first-ever pediatric device for infants and children. The pediatric device is offered with three different kinds of cannulas, made of high-quality medical silicon, to address anatomical differences in patients. The EXCOR Pediatric blood pump has five volume choices ranging from 10 ml to 60 ml depending on a patient's weight and body surface. The entire device is powered by a laptop computer installed in the Ikus driving unit that powers the pump. The EXCOR Pediatric unit has triple redundancy to the system to ensure patient safety and device reliability.
The inflow cannula is implanted into the left ventricle with the outflow being attached to the aorta. Essentially, the Berlin Heart is acting as the left ventricle. An additional device may be implanted in to the right ventricle if full support is necessary. Although VADs are commonly used in adult patient populations, there have not been any devices available for children under the age of 3 or infants. The Berlin Heart offers the first real hope for many pediatric patients. "The Berlin Heart allows us to support the circulation of critically ill children awaiting heart transplantation - especially infants - more safely than with previously used devices," said Dr. Kirk Kanter, Chief of Cardiothoracic Surgery at Children's Sibley Heart Center and professor of cardiothoracic surgery at Emory University School of Medicine. "With the Berlin Heart, we can get children waiting for a transplant off the ventilator, walking around and eating - making them better candidates for heart transplantation when a suitable donor does become available." The Berlin Heart has not yet been fully approved by the Food and Drug Administration (FDA); however, CHOA has been granted permission to use the device as a bridge to transplant on a case-by-case compassionate-use basis. Compassionate use is a term used to define the provision of experimental medications or treatments prior to final FDA approval. According to Dr. Brian Kogon, pediatric cardiothoracic surgeon at CHOA Sibley Heart Center and Chief of Adult Congenital Cardiothoracic Surgery and assistant professor at Emory University School of Medicine, patients are considered for the Berlin Heart only when all other options have been exhausted and it is determined that the heart will not recover of its own accord. At that point, the steps to implant a Berlin Heart device take place. "When we have patients who present with cardiomyopathy, we go through many steps to support the heart in hopes that they will recover using everything from medication to mechanical support," said Dr. Kogon. ECMO, a heart-lung bypass, has been the standard in supporting critically ill children awaiting heart transplantation. The patient must be sedated with a paralytic agent to be placed on the ECMO device. The rate of complications is significant with patients on ECMO. "This device is much more invasive, with less than half of the patients surviving until transplantation is available," said Dr. William Mahle, Medical Director of Clinical Research and pediatric cardiologist at CHOA Sibley Heart Center. Dr. Mahle is also associate professor of pediatrics at Emory University School of Medicine. "Of the patients that are on ECMO, there is an 80% increased chance that they will reject their donor heart when it is implanted as well as an 80% increased chance of death within the first five years," said Dr. Mahle. The Berlin Heart only supports the heart rather than the heart and lungs and therefore the patient can be awake and ambulatory unlike ECMO. Patients can also be on the device for an extended period of time if necessary. Heart failure causes children to lose weight or not to gain weight at all. "The Berlin Heart can prevent this from happening and therefore these children are much healthier going into the transplant," said Dr. Mahle. The EXCOR Pediatric VAD is similar to other devices in that a pneumatic device is used that squeezes with each heart beat. "The Berlin Heart is much smaller, which is why it is ideal for pediatric patients," said Dr. Mahle. "The challenge is that there is an increased risk of clotting within the pump, which is why heparin or warfarin is given to address these issues." While the internal device is not reused, the external pumping device that powers the Berlin Heart is rotated among hospitals. The demand for the device is ever increasing and there is a wait, although according to the staff at CHOA, the manufacturer has been extremely responsive in expediting delivery. "We enjoy having the Berlin Heart as an option because there are few choices in children who are small," said Dr. Kogon. In fact, at the time of this interview, Dr. Kogon was preparing to do a potential Berlin Heart procedure the following day on a 1-month-old female whose heart was not showing signs of improvement. To date, more than 200 Berlin Heart procedures have been performed in the United States. The pediatric cardiac surgeons led by Dr. Kanter rely heavily on the team approach to make the process of implanting the Berlin Heart a success. There are four heart transplant coordinators, critical care nursing staff and cardiac intensive care support staff. The research team deals with all of the FDA paperwork and is responsible for getting the device to the surgical team. Anesthesia, surgical attendings and residents, perfusionists, blood bank staff and post-op care are all involved, along with many others. "It is important to have all of these areas of expertise to make the chances of success high," said Dr. Kogon. "The Berlin Heart opens up the repertoire of what we can do and the services we can provide to our patients," said Dr. Mahle. Dr. Mahle reports that 18% of infants have died while waiting for a donor heart. He has high hopes that the Berlin Heart will greatly reduce this number in the future. Dr. Mahle offers the following advice to other physicians and centers who are considering pursuing the Berlin Heart procedure as an option. "You must have a team in place before you get the first patient because of the detailed process. Anticoagulants and management of blood products are essential and you must have a lot of experience with ventricular-assist devices to be successful." Dr. Mahle also recommends that the nursing staff be well trained in the post-op care of the patients receiving the Berlin Heart and in fact the manufacturer recommends that the same person be in charge of post-op wound care. Although the cost of this cutting-edge procedure can exceed $100,000, CHOA supports its use and Dr. Mahle reports that most major insurers are supportive of the device and therefore this should not be a barrier to treatment. The physicians and staff at CHOA are very proud of the fact that the Berlin Heart procedure is now an option for their most medically fragile pediatric patients. "This device has allowed a child who would not have survived for transplantation to have an option," said Dr. Kogon. "We have a center that has the personnel who can do this kind of complex procedure." The significance of CHOA offering this type of surgical option is crucial for the state of Georgia and the region. "Children's has always offered comprehensive cardiac care, which means a child should never have to leave the state for the care they need," said Dr. Mahle. "We are strongly committed to this." The Berlin Heart is just one real-life example of how technology is improving daily and offering new options to patients who once had no options. "This extraordinary possibility has allowed these kids to survive and live a normal life," said Dr. Kogon. Dr. Mahle agrees and went on to say, "The Berlin Heart has gone from being a novelty to an important tool for treating critically ill children." The devoted team at CHOA helped young Yasir have a new chance at life with the use of the Berlin Heart and a successful heart transplant. The hope at CHOA is that many more children will live to see many more birthdayswith use of this dynamic technology in the hands of a skilled and talented team.