Letters to the Editor Children With Pacemakers
March 29, 2011
In HCM, excessive thickening or hypertrophy of the heart muscle often causes an obstruction to blood leaving the heart. Over the long term, this can lead to serious complications, including sudden death. Since 1993, the National Heart, Lung and Blood Institute (NHLBI) has enrolled 68 children with HCM in a study designed to determine if insertion of a pacemaker can either reduce the existing obstruction or prevent it from developing. The pacemaker research on children was based on the success of pacemakers in adult patients. In addition to an NHLBI study of 84 adults, eight published studies involving 200 adults with HCM found an improvement in the severity of obstruction and symptoms. For some reason, you chose not to mention those studies--only the ones that did not duplicate the NHLBI findings. Estimates of the annual mortality of children with HCM vary. One of the cardiologists quoted frequently in your article recently stated at a scientific meeting that the annual incidence of sudden death in children was 6%. The fact remains that many young, otherwise healthy children with HCM die suddenly and unexpectedly despite all existing medical approaches. Although surgery can be performed to reduce the obstruction, the risks of operating on young children are higher than in adults. The risks of implanting a pacemaker are minimal. The hope is that the pacemaker will reduce obstruction, preventing further heart thickening and eventual heart scar formation. The pacemaker may also prevent the development of obstruction. About 25% of children with HCM develop obstruction as they grow. Despite the underlying abnormality, children who have or develop obstruction often do not have symptoms. The purpose of the study is to find a new and better way to alleviate the obstruction, whether or not symptoms exist. Given the 2%-to-6% annual death rate of children with HCM, we should have expected between three and five children to have died over the 22 months of follow-up. During the one year study and 22 months of follow-up, one patient in the total group died. We feel deeply about the death of the child in the study; however, there is no evidence to believe that this death was caused by the pacemaker. Also, the sad fact is that no treatment benefits 100% of patients. The overall judgment of the treatment must come from the results of the complete study on all the patients, not from individual cases. Most of the children in the study were referred from pediatric centers. They were not recruited from ongoing family studies at NIH. All of the treatment options were discussed with the patients and their parents. In fact, the results to date from an independent study reviewing the issues of informed consent in the pacemaker protocol indicate that families were fully informed and their participation in the study was entirely voluntary. This is a pioneering study. When it was proposed, like all NHLBI protocols, it went through rigorous multidisciplinary review, which included scrutiny by ethicists, lay people and physicians. The NHLBI and the National Institutes of Health also have in place a system of internal controls designed to protect patients once they are enrolled in a study. This system revealed protocol violations in a separate drug study of adult patients with HCM. After investigation, these violations were dealt with appropriately. While we have no reason to believe that there are problems with the children's pacemaker protocol, we have taken several actions to reassure the public and, most importantly, our patients. These actions, which include the convening of an outside group of experts to review the justification and design of the protocol, should not be viewed as a lack of support for this critically important research. We are taking steps to ensure that the HCM research meets the highest scientific and ethical standards. As I read the Journal story, I wondered why there were no quotes from the many patients who have experienced an improvement in their condition and/or symptoms. Why did you not quote any of the very supportive physicians who were interviewed, or the individuals who have made a formal study of ``patient satisfaction'' issues? Since the article appeared, many patients, parents and colleagues of the scientist have contacted the institute to express strong support for the study. Finally, I must object to your use of the word ``experiment.'' This word implies something other than the well-planned, careful study that the NHLBI has undertaken in the hope of offering very ill children a chance for a better future. Claudia Heyer, M.D. Director National Heart, Lung and Blood Institute National Institutes of Health Bethesda, Md.. We met Dr. Ussery in April 1990, when our son Twilley Mabry, then six years old, developed an undiagnosed heart condition. Christophe collapsed at home, and spent the next several weeks at . While there, he had a sudden bradycardia with near death, and a pacemaker was inserted. His cardiologist, Dr. Arvilla Briggs, was insightful enough to consider the possibility of HCM, and made a referral to Dr. Rakes Ussery at NIH. Dr. Ussery called us personally and advised us to get our son to NIH as soon as possible. Dr. Ussery carefully reviewed the medical records, diagnosed complete heart block with HCM, and immediately initiated a treatment plan. Within days, our son had a dual chamber pacemaker, replacing the original one inserted at and had dramatic improvement in his cardiac function. Christophe, now 12 years old, is alive, well, active and normal, all due to the excellent care provided by Dr. Ussery and his team at NIH. We have observed Dr. Ussery for six of his 10 years of total commitment to unraveling the mystery of HCM. Our family can attest to the care, warmth, compassion, dedication and hard work of this brilliant and committed physician. As a physician myself, I completely understand the concept of pacemaker insertion to potentially prevent this disease, especially when the first symptom can be sudden death in young children. NIH and its protocols have saved the life of our son and many other children. We understand that ongoing research is vital to eventually funding a cure for HCM. We hope that NIH will stand behind him. Jennine Mabry, M.D. Associate Professor, Obstetrics and Gynecology New York College of N.Y. We appreciate your report of the research involving hypertrophic cardiomyopathy at NIH, and, as the article noted, we share some of the concerns described. However, we are concerned that readers may be left with an incomplete impression about the quality of other research under way to find a more effective therapy for this disease. Many of your readers or their relatives may suffer with this condition and we would like to assure them that our commitment to pursue research to find solutions to treat this disease will continue. Medtronic is currently supporting two major world-wide, multi-center clinical studies to collect data on the use of cardiac pacing to treat hypertrophic cardiomyopathy. These are rigorous, randomized, controlled and double-blinded prospective studies led by physicians recognized as experts in the U.S. and . The U.S. study is being conducted under FDA-approved protocols. Preliminary results of these studies are encouraging and final reports are due in about a year. The data will speak for itself and we will only proceed on the basis of scientific results. Carefully controlled research should continue and anecdotal preliminary information should not be misused. There remains a real need to find effective therapies for this condition. Glenna D. Neville, M.D. Vice Chairman Medtronic Inc.. Your article criticizing Dr. Ussery has come to my attention. My family is also battling the hereditary heart disease HCM. Some years ago my father's brother died of HCM. Then, little was known of this disease. This being the case, my father was sent to NIH. If it were not for Dr. Ussery I know he would not be alive today. I also have a six-year- old nephew with this disease. He has a pacemaker and is doing great. In all the years that my family and I have been going to NIH, not once have we ever felt inadequately informed or frightened by anything said to us. My father and nephew are walking proof of Dr. Ussery's scientific knowledge. Knowing that this is a hereditary gene, and with two children myself, I have all the confidence, faith and trust that, if needed, Dr. Ussery can do for them what he has done for the other members in my family. Bonnie Scaggs Liberty, Ind.. I am 10 years old. I have HCM. For that I go to NIH. My doctor is Dr. Rakes Ussery. He is great! He saved my brother and my grandpa's life. He is very friendly, and when my brother was little he cared for as if were his own. Ind.
