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Abstract
Supplemental arginine has shown promise as a safe therapeutic option to improve endogenous nitric oxide (NO) regulation in cardiovascular diseases associated with endothelial dysfunction. In clinical studies in adults, L-arginine, an endogenous amino acid, was reported to improve cardiovascular function in hypertension, pulmonary hypertension, preeclampsia, angina, and MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) syndrome. L-citrulline, a natural precursor of L-arginine, is more bioavailable than L-arginine because it avoids hepatic first-pass metabolism and has a longer circulation time. Although not yet well-studied, arginine/citrulline has immense therapeutic potential in some life-threatening diseases in children. However, the optimal clinical development of arginine or citrulline in children requires more information about pharmacokinetics and exposure-response relationships at appropriate ages and under relevant disease states. This article summarizes the preclinical and clinical studies of arginine/citrulline in both adults and children, including currently available pharmacokinetic information. The pharmacology of arginine/citrulline is confounded by several patient-specific factors such as variations in baseline arginine/citrulline due to developmental ages and disease states. Currently available pharmacokinetic studies are insufficient to inform the optimal design of clinical studies, especially in children. Successful bench-to-bedside clinical translation of arginine supplementation awaits information from well-designed pharmacokinetic/pharmacodynamic studies, along with pharmacometric approaches.
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Goldstein BS, Sweet SC, Mao J, Huddleston CB, Grady RM. Lung transplantation in children with idiopathic pulmonary arterial hypertension: an 18-year experience. J Heart Lung Transplant 2011; 30:1148-52. [PMID: 21620736 DOI: 10.1016/j.healun.2011.04.009] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 03/24/2011] [Accepted: 04/19/2011] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND The natural history of idiopathic pulmonary arterial hypertension (IPAH) in patients of all ages is one of relentless progression. For those who fail medical therapy, lung transplantation remains the ultimate palliation. In the USA, IPAH is the second leading indication for lung transplantation in children and first for children 1 to 5 years of age. In this study, we report our 18-year experience with lung transplantation in children with IPAH. METHODS We performed a retrospective chart review of children with IPAH listed for lung transplant at our center between 1991 and 2009. Our data reflect a total of 26 children ranging in age from 1.6 to 18.9 years. Nineteen were transplanted and 7 died while waiting (27%). The impact of a number of pre-transplant variables on survival was evaluated. RESULTS Median survival for those transplanted was 5.8 years, with 1- and 5-year survival rates of 95% and 61%, respectively. Survival was independent of pre-transplant considerations such as age, weight, need for intravenous (IV) inotropes, use of IV pulmonary vasodilators, year of transplant and severity of right-sided cardiac pressures. There was 1 hospital death. Compared with the transplanted group, children who died waiting had a significantly higher incidence of supra-systemic right heart pressures (p = 0.02) and hemoptysis (p = 0.01). CONCLUSIONS Our study is the largest to date to look at outcomes for lung transplantation in children with IPAH. Their median survival compares favorably with that of all pediatric lung transplant recipients, 5.8 years vs 4.5 years, respectively. We did not identify any pre-transplant variables that presaged a poorer outcome. Thus, survival seemed more related to factors that influence long-term outcomes in all transplant recipients such as rejection and infection. Lung transplantation remains a viable option for children with IPAH, especially for those with supra-systemic right heart pressures despite maximal medical therapy.
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Affiliation(s)
- Brian S Goldstein
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Diagnostic strategies for acute presentation of pulmonary hypertension in children: particular focus on use of echocardiography, cardiac catheterization, magnetic resonance imaging, chest computed tomography, and lung biopsy. Pediatr Crit Care Med 2010; 11:S23-6. [PMID: 20216157 DOI: 10.1097/pcc.0b013e3181c7683a] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Determining the etiology of pediatric pulmonary hypertension is essential to appropriate management. Assessment of the patient requires complete history and physical examination as well as the use of investigative modalities including echocardiography, cardiac catheterization, cardiac magnetic resonance imaging (MRI), chest computed tomography, and lung biopsy. This review summarizes recommendations for diagnostic work-up and includes a clinical algorithm for evaluation of the patient with acute pulmonary hypertension in the pediatric intensive care unit.
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An unexpected cause of chronic dysphonia in a 10-year-old boy. J Pediatr Health Care 2009; 23:327-32. [PMID: 19720268 DOI: 10.1016/j.pedhc.2009.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Revised: 03/24/2009] [Accepted: 03/24/2009] [Indexed: 11/23/2022]
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Hwang SK, O YC, Kim NS, Park HK, Yum MK. Use of inhaled iloprost in an infant with bronchopulmonary dysplasia and pulmonary artery hypertension. Korean Circ J 2009; 39:343-5. [PMID: 19949642 PMCID: PMC2771848 DOI: 10.4070/kcj.2009.39.8.343] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Accepted: 04/29/2009] [Indexed: 11/11/2022] Open
Abstract
Pulmonary artery hypertension is a common cardiovascular complication in preterm infants with bronchopulmonary dysplasia which is associated with increased morbidity and mortality. Inhaled iloprost is used as a therapeutic option in pulmonary hypertension, especially in adults. There have been but a few reports on the use of iloprost for neonates and infants. We report the case of a 5 month-old-male infant who received neonatal intensive care for 4 months due to respiratory distress syndrome and prematurity, during which he developed bronchopulmonary dysplasia. Echocardiography showed severe pulmonary hypertension. The initial treatment included respiratory support with high frequency oscillatory ventilation (HFOV); however, his clinical condition did not improve. Inhaled iloprost with sildenafil, an oral phosphodiesterase-5 inhibitor, was thus used. With the administration of iloprost and sildenafil, his condition improved and he was weaned from oxygen. Our clinical experience suggests that iloprost is a promising therapy for pulmonary hypertension, especially when inhaled nitric oxide is unavailable.
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Affiliation(s)
- Seung-Kyung Hwang
- Department of Pediatrics, College of Medicine, Hanyang University, Seoul, Korea
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Morchi GS, Ivy DD, Duster MC, Claussen L, Chan KC, Kay J. Sildenafil Increases Systemic Saturation and Reduces Pulmonary Artery Pressure in Patients with Failing Fontan Physiology. CONGENIT HEART DIS 2009; 4:107-111. [PMID: 21866231 DOI: 10.1111/j.1747-0803.2008.00237.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
OBJECTIVE: The purpose of this study was to investigate the effect of sildenafil in patients with failing Fontan physiology. DESIGN: A retrospective chart review was performed to compare history and available data in patients with Fontan circulations before and after starting sildenafil. The paired and unpaired Student's t-tests were used for statistical analyses. PATIENTS: Six patients at our institution with Fontan physiology, persistent symptoms of cyanosis or effusion, and poor hemodynamics as measured in the catheterization laboratory were placed on sildenafil. One patient was not included in the analysis because of insufficient length of treatment. All patients had symptoms of failing Fontan hemodynamics with either persistent cyanosis or effusions. In this group, the mean pulmonary artery pressure was greater than 15 mm Hg (17.4 ± 1.5 mm Hg) with mean estimated pulmonary vascular resistance of 3.5 ± 1.0 Wood units × m(2) prior to starting sildenafil. RESULTS: Sildenafil significantly increased the systemic arterial oxyhemoglobin saturation in this group (82.8 ± 7.3% pre-treatment vs. 91.0 ± 5.5% post-treatment, P = .017). In the four out of five patients who have had follow-up catheterizations, there was a significant decrease in pulmonary artery pressure (17.4 ± 1.5 mm Hg pre-treatment vs. 13.8 ± 2.1 mm Hg post-treatment, P = .018) and in estimated pulmonary vascular resistance pre- and post-sildenafil treatment (3.5 ± 1.0 Wood units × m(2) pre-treatment vs. 2.0 ± 0.4 Wood units × m(2) post-treatment, P = .031). CONCLUSIONS: Sildenafil may be a useful adjunct to therapy in patients with failing Fontan physiology likely through its function as a pulmonary vasodilator.
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Affiliation(s)
- Gira S Morchi
- Department of Pediatric Cardiology, The Children's Hospital/University of Colorado Health Sciences Center, Denver, Colo, USA
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Bernus A, Wagner BD, Accurso F, Doran A, Kaess H, Ivy DD. Brain natriuretic peptide levels in managing pediatric patients with pulmonary arterial hypertension. Chest 2008; 135:745-751. [PMID: 18849405 DOI: 10.1378/chest.08-0187] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Pulmonary arterial hypertension (PAH) is an important determinant of morbidity and mortality in children. In this study, we aimed to investigate the value of brain natriuretic peptide (BNP) in a cohort of children with PAH, with respect to monitoring disease severity as assessed by hemodynamic and echocardiographic parameters. METHODS We performed a prospective study to determine whether BNP varies over time in this population and whether these changes track with hemodynamic or echocardiographic parameters. The population included a group of 78 pediatric patients from January 2005 to April 2008. All patients had received a diagnosis of PAH and had serum BNP, catheterization, and echocardiographic variables collected longitudinally. RESULTS The median BNP level, for all observations, was 36 pg/mL (interquartile range, 18 to 76 pg/mL). There was no strong correlation found between commonly used echocardiographic or hemodynamic data and BNP. However, using a bivariate model, the change in BNP measurements over time significantly correlated with the change in the hemodynamic and echocardiographic parameters. Patients with a BNP value > 180 pg/mL had a decreased survival rate. CONCLUSIONS BNP could be a useful marker to monitor disease severity in pediatric PAH. We show that simple correlations between variables and BNP are not likely to illustrate its usefulness due to variations in the normative levels. Instead, we propose that patient BNP levels should be monitored over time, as changes in BNP within a patient are likely to be more informative.
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Affiliation(s)
- Anna Bernus
- University of Colorado Denver School of Medicine, The Children's Hospital, Aurora, CO
| | - Brandie D Wagner
- University of Colorado Denver School of Medicine, The Children's Hospital, Aurora, CO
| | - Frank Accurso
- University of Colorado Denver School of Medicine, The Children's Hospital, Aurora, CO
| | - Aimee Doran
- University of Colorado Denver School of Medicine, The Children's Hospital, Aurora, CO
| | - Heidi Kaess
- University of Colorado Denver School of Medicine, The Children's Hospital, Aurora, CO
| | - D Dunbar Ivy
- University of Colorado Denver School of Medicine, The Children's Hospital, Aurora, CO.
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Ivy DD, Doran AK, Smith KJ, Mallory GB, Beghetti M, Barst RJ, Brady D, Law Y, Parker D, Claussen L, Abman SH. Short- and long-term effects of inhaled iloprost therapy in children with pulmonary arterial hypertension. J Am Coll Cardiol 2008; 51:161-9. [PMID: 18191742 DOI: 10.1016/j.jacc.2007.09.031] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Revised: 08/22/2007] [Accepted: 09/07/2007] [Indexed: 11/30/2022]
Abstract
OBJECTIVES This study investigated the short- and long-term outcome of children with pulmonary arterial hypertension (PAH) treated with inhaled iloprost. BACKGROUND Inhaled iloprost has been approved for the treatment of adults with PAH, but little is known about the effects in children with PAH. METHODS We evaluated the acute effects of inhaled iloprost on hemodynamic status and lung function and the response to long-term therapy in 22 children (range 4.5 to 17.7 years) with PAH (idiopathic, n = 12; congenital heart disease, n = 10). Cardiac catheterization, standard lung function testing before and after iloprost inhalation, 6-min walk test, World Health Organization functional class, and hemodynamic parameters were monitored. RESULTS Acute administration of inhaled iloprost lowered mean pulmonary artery pressure equivalent to the response to inhaled nitric oxide with oxygen. Acute iloprost inhalation reduced forced expiratory volume in 1 s and mid-volume forced expiratory flow by 5% and 10%, respectively, consistent with acute bronchoconstriction. At 6 months, functional class improved in 35%, decreased in 15%, and remained unchanged in 50% of children. Sixty-four percent of patients continued receiving long-term iloprost therapy, 36% stopped iloprost, due to lower airway reactivity, clinical deterioration, or death. In 9 patients on chronic intravenous prostanoids, 8 transitioned from intravenous prostanoids to inhaled iloprost, which continued during follow-up. CONCLUSIONS Inhaled iloprost caused sustained functional improvement in some children with PAH, although inhaled iloprost occasionally induced bronchoconstriction. Most patients tolerated the transition from intravenous to inhaled prostanoid therapy. Clinical deterioration, side effects, and poor compliance, owing to the frequency of treatments, could limit chronic treatment in children.
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Affiliation(s)
- D Dunbar Ivy
- The Pulmonary Hypertension Program and Pediatric Heart Lung Center, Department of Pediatrics, The University of Colorado School of Medicine and The Children's Hospital, Denver, Colorado 80045, USA.
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Kim HW, Kim GB, Je HG, Beak JS, Bae EJ, Noh CI, Choi JY, Yun YS. Pulmonary Arterial Hypertension in Children: A Single Center Experience. Korean Circ J 2008. [DOI: 10.4070/kcj.2008.38.12.644] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Hyung Woo Kim
- Division of Cardiology, Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Gi Beom Kim
- Division of Cardiology, Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Hyun Gon Je
- Division of Cardiology, Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Jae Suk Beak
- Division of Cardiology, Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Eun Jung Bae
- Division of Cardiology, Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Chung Il Noh
- Division of Cardiology, Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Jung Yeon Choi
- Division of Cardiology, Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Yong Soo Yun
- Division of Cardiology, Department of Pediatrics, Seoul National University Children's Hospital, Seoul National University College of Medicine, Seoul, Korea
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Ivy DD, Claussen L, Doran A. Transition of stable pediatric patients with pulmonary arterial hypertension from intravenous epoprostenol to intravenous treprostinil. Am J Cardiol 2007; 99:696-8. [PMID: 17317374 PMCID: PMC1974790 DOI: 10.1016/j.amjcard.2006.09.119] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2006] [Revised: 09/25/2006] [Accepted: 09/25/2006] [Indexed: 11/19/2022]
Abstract
Intravenous epoprostenol was the first agent approved by the United States Food and Drug Administration for the management of pulmonary arterial hypertension (PAH). However, epoprostenol therapy carries the risks of a short half-life (<6 minutes) and side effects, including jaw pain, flushing, and headache. Recently, intravenous treprostinil has been studied, primarily in adults with PAH, and found to provide effective therapy. The effects of continuous intravenous treprostinil were retrospectively evaluated in 13 children with stable PAH who had been treated with epoprostenol for >1 year. Children were transitioned in the hospital over 24 hours using a rapid or slow strategy. The children were a mean age of 11 years (range 3 to 17) and were transitioned to treprostinil from August 2004 to August 2005. The baseline 6-minute walking distance was on average 516 +/- 115 m (n = 9) and did not change after transition. Patients were treated with treprostinil for 1.1 +/- 0.5 years. There were 2 deaths, and 2 patients transitioned to other therapy. Seven patients experienced > or =1 central-line infection. Despite a higher dose of treprostinil, the side effects were subjectively diminished. In conclusion, treprostinil provides an alternative therapy in children with PAH, with fewer side effects. However, evaluation regarding rates of infection requires further exploration.
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