School age and adolescent heart failure following the Norwood procedure.

BACKGROUND: Heart failure results in significant morbidity and mortality for young children with hypoplastic left heart syndrome (HLHS) following the Norwood procedure. The trajectory in later childhood is not well described. METHODS: We studied the outcome into adolescence of participants enrolled in the Single Ventricle Reconstruction trial who underwent the Fontan procedure or survived to 6 years without having undergone Fontan procedure. The primary outcome was heart failure events, defined as heart transplant listing or death attributable to heart failure. Symptomatic heart failure for participants surviving 10 or more years was also assessed utilizing the Pediatric Quality of Life Inventory (PedsQL). RESULTS: Of the 345 participants who underwent a Fontan operation or survived to 6 years without Fontan, 25 (7.2%) had a heart failure event before the age of 12 years. Among these, 21 were listed for heart transplant, and 4 died from heart failure. Nineteen participants underwent heart transplant, all of whom survived to age 12 years. Factors associated with a heart failure event included longer Norwood hospital length of stay, aortic atresia, and no Fontan operation by age 6 years. Assessment of heart failure symptoms at 12 years of age revealed that 24 (12.2%) of 196 PedsQL respondents "often" or "almost always" had difficulty walking more than one block. CONCLUSIONS: Heart failure events occur in over 5% of children with palliated HLHS between preschool age and adolescence. Outcomes for children listed for transplant are excellent. However, a substantial portion of palliated HLHS children have significant symptoms of heart failure at 12 years of age.

Extracardiac Findings on Cardiac Magnetic Resonance: A Children's Hospital Experience.

Cardiac magnetic resonance (CMR) incorporates a field of view that has the potential to capture clinically relevant extracardiac findings (ECF); however, there has been minimal investigation of ECF prevalence in children's hospitals, where the patient population varies in age and diagnosis. We retrospectively reviewed consecutive, clinically indicated, CMR studies performed at a tertiary care children's hospital during a 1-year period from January 1 to December 31, 2019. ECFs were classified as significant or non-significant based on whether they were described in the final impression of the CMR report. A total of 851 distinct patients had a CMR study during the 1-year period. Mean age was 19.5 (range 0.2; 74.2) years. A total of 254 ECFs were present in 158 of the 851 studies (18.6%) with 9.8% of all studies having significant ECFs. A total of 40.2% of ECFs were previously unknown and 9.1% (23/254) of ECFs included further recommendations (2.1% of all studies). ECFs were most often found in the chest (48%) or abdomen/pelvis (46%). Three patients were incidentally found to have malignancy (renal cell, thyroid, and hepatocellular carcinoma). Comparing studies with significant ECFs to the group without, CMR indications for biventricular CHD (43% vs 31%, p = 0.036), single ventricle CHD (12% vs 3.9%, p = 0.002), and aortopathy/vasculopathy (16% vs 7.6%, p = 0.020) were more common. The odds of significant ECF increased with increasing age (OR 1.82, 95% CI 1.10-3.01) and increased most notably between ages 14 to 33 years old. Recognition of the high percentage of ECFs remains important for timely diagnosis of these incidental findings.

Arrhythmia Burden and Heart Rate Response During Exercise in Anderson-Fabry Disease.

Patients with Anderson-Fabry disease (AFD) have an elevated incidence of resting arrhythmias and ischemic heart disease, but their exercise arrhythmia burden and ischemic changes are not well understood. In addition, little research has been done on heart rate recovery in these patients. We retrospectively reviewed charts of patients with AFD who underwent maximal effort cardiopulmonary exercise testing (CPET) (n=44; 38.2 ± 13.8 yr; 23 men) from 2012 through 2018. Electrocardiographic, Holter monitoring, echocardiographic, cardiac magnetic resonance imaging, and patient demographic data were collected. No patient had adverse events that necessitated CPET termination, whereas 25 (57%) had ectopy during CPET, including 3 (7%) with frequent premature atrial contractions and 5 (11%) with frequent premature ventricular contractions. The ectopic burden was higher during resting electrocardiographic monitoring before exercise. In addition, 7 patients (16%) had pathologic ST-segment or T-wave changes on CPET, defined as ST-segment changes ≥2 mm. Among the patients who had concurrent cardiac magnetic resonance findings with their CPET (n=27), ST-segment or T-wave changes were associated with left ventricular myocardial mass (r=0.43, P=0.02). Chronotropic incompetence was seen during CPET in 28 patients (64%); however, only 2 patients (4%) had abnormal heart rate recovery at 1 minute. This study shows that patients with AFD can safely undergo exercise testing but have a high incidence of exercise-induced arrhythmias and ischemic changes. Ischemic electrocardiographic changes during exercise testing are associated with myocardial mass. Despite the chronotropic incompetence associated with AFD, heart rate recovery appears to be generally preserved in these patients.

Baja incidencia de cardiopatía clínicamente significativa en niños en edad escolar tras padecer COVID-19 / The low incidence of clinically significant heart disease in school-age children following COVID-19

No es clara la carga de morbimortalidad de la lesión cardíaca clínicamente evidente secundaria a la enfermedad por coronavirus de 2019 (COVID-19) en los niños en edad escolar. A lo largo de 12 meses, en un importante hospital pediátrico académico en la región del medio oeste de Estados Unidos, hubo 1481 casos de COVID-19 sin hospitalización en niños en edad escolar por lo demás sanos, en quienes se hicieron 195 pruebas cardíacas. Si bien aparecieron hallazgos fortuitos, no se descubrió ninguna patología cardíaca relacionada con la COVID-19. Además, ~3 % de los niños solamente tuvieron síntomas cardíacos agudos que requirieron una evaluación por el área de cardiología pediátrica. Los niños que no fueron hospitalizados por COVID-19 tienen un riesgo muy bajo de desarrollar daño cardíaco clínicamente significativo y son más propensos a presentar hallazgos fortuitos.

The burden of clinically-apparent cardiac injury secondary to coronavirus disease 2019 (COVID-19) in school-age children is unclear. Over 12 months at a large academic pediatric hospital in the Midwestern portion of the United States, there were 1481 COVID-19 positive non-hospitalized otherwise healthy schoolaged children with 195 having cardiac testing performed. While incidental findings occurred, no definitive COVID-19 related cardiac pathology was discovered. Additionally, only ~3 % of children had acute cardiac symptoms necessitating evaluation by pediatric cardiology. School-age children who were not hospitalized for COVID-19 have a very low risk of having clinically significant cardiac damage and are more likely to discover incidental findings.

Myocardial Parametric Mapping by Cardiac Magnetic Resonance Imaging in Pediatric Cardiology and Congenital Heart Disease.

Parametric mapping, that is, a pixel-wise map of magnetic relaxation parameters, expands the diagnostic potential of cardiac magnetic resonance by enabling quantification of myocardial tissue-specific magnetic relaxation on an absolute scale. Parametric mapping includes T1 mapping (native and postcontrast), T2 and T2* mapping, and extracellular volume measurements. The myocardial composition is altered in various disease states affecting its inherent magnetic properties and thus the myocardial relaxation times that can be directly quantified using parametric mapping. Parametric mapping helps in the diagnosis of nonfocal disease states and allows for longitudinal disease monitoring, evaluating therapeutic response (as in Thalassemia patients with iron overload undergoing chelation), and risk-stratification of certain diseases. In this review article, we describe various mapping techniques and their clinical utility in congenital heart disease. We will also review the available literature on normative values in children, the strengths, and weaknesses of these techniques. This review provides a starting point for pediatric cardiologists to understand and implement parametric mapping in their practice.

Rapid cardiac MRI protocol for cardiac assessment in paediatric and young adult patients undergoing haematopoietic stem cell transplant: a feasibility study.

BACKGROUND: Haematopoietic stem cell transplantation is an important and effective treatment strategy for many malignancies, marrow failure syndromes, and immunodeficiencies in children, adolescents, and young adults. Despite advances in supportive care, patients undergoing transplant are at increased risk to develop cardiovascular co-morbidities. METHODS: This study was performed as a feasibility study of a rapid cardiac MRI protocol to substitute for echocardiography in the assessment of left ventricular size and function, pericardial effusion, and right ventricular hypertension. RESULTS: A total of 13 patients were enrolled for the study (age 17.5 ± 7.7 years, 77% male, 77% white). Mean study time was 13.2 ± 5.6 minutes for MRI and 18.8 ± 5.7 minutes for echocardiogram (p = 0.064). Correlation between left ventricular ejection fraction by MRI and echocardiogram was good (ICC 0.76; 95% CI 0.47, 0.92). None of the patients had documented right ventricular hypertension. Patients were given a survey regarding their experiences, with the majority both perceiving that the echocardiogram took longer (7/13) and indicating they would prefer the MRI if given a choice (10/13). CONCLUSION: A rapid cardiac MRI protocol was shown feasible to substitute for echocardiogram in the assessment of key factors prior to or in follow-up after haematopoietic stem cell transplantation.

Myocardial fibrosis, diastolic dysfunction and elevated liver stiffness in the Fontan circulation.

INTRODUCTION: Single ventricle diastolic dysfunction and hepatic fibrosis are frequently observed in patients with a Fontan circulation. The relationship between adverse haemodynamics and end-organ fibrosis has not been investigated in adolescents and young adults with Fontan circulation. METHODS: Prospective observational study of Fontan patients who had a cardiac catheterisation. Cardiac MRI with T1 mapping was obtained to measure extracellular volume (ECV), a marker of myocardial fibrosis. Hepatic magnetic resonance elastography was performed to assess liver shear stiffness. Serum biomarkers of fibrosis including matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) were measured. Very high ECV was defined as >30% and elevated serum biomarkers as >75th percentile for each biomarker. RESULTS: 25 Fontan patients (52% female) with mean age of 16.3±6.8 years were included. Mean ECV was 28%±5%. There was a significant correlation between ECV and systemic ventricular end-diastolic pressure (r=0.42, p=0.03) and between ECV and liver stiffness (r=0.45, p=0.05). Patients with elevated ECV demonstrated elevations in MMPs and TIMPs. Similarly, patients with elevated MMPs and TIMPs had greater liver stiffness compared with patients with normal levels of these biomarkers. CONCLUSIONS: In Fontan patients, cardiac magnetic resonance evidence of myocardial fibrosis is associated with diastolic dysfunction, increased liver stiffness and elevated circulating biomarkers of fibrosis. These findings suggest the presence of a profibrotic milieu, with end-organ implications, in some patients with Fontan circulation.

Cardiovascular magnetic resonance imaging derived septal curvature in neonates with bronchopulmonary dysplasia associated pulmonary hypertension.

BACKGROUND: Bronchopulmonary dysplasia (BPD) associated with pulmonary hypertension (PH) is a significant source of morbidity and mortality in premature infants. Recent advances have allowed the use of cardiovascular magnetic resonance (CMR) in the assessment of respiratory and cardiac disease in infants with BPD. In adults and older pediatric patients, decreased CMR interventricular septal curvature correlates with increased mean pulmonary artery pressure and pulmonary vascular resistance. The current study sought to determine the relationship of CMR derived septal curvature in neonates with BPD and BPD-PH with a need for PH therapy. METHODS: Forty moderate or severe BPD and 12 mild BPD or control infants were imaged without contrast between 38 and 47 weeks post-menstrual age on a neonatal-sized, neonatal intensive care unit-sited 1.5 T CMR scanner. CMR indices including eccentricity index (CMR-EI) and septal curvature were measured and compared to BPD severity and clinical outcomes including hospital length of stay (LOS), duration of respiratory support, respiratory support level at discharge and PH therapy. RESULTS: CMR-EI was directly associated and septal curvature was inversely associated with BPD severity. In a univariate analysis, CMR-EI and septal curvature were associated with increased hospital LOS, duration of respiratory support, respiratory support at hospital discharge, and need for PH therapy. In multivariable analysis CMR-EI was associated with hospital LOS and duration of respiratory support and septal curvature was associated with respiratory support at hospital discharge. Septal curvature was the only clinical or CMR variable associated with need for PH therapy (R2 = 0.66, p = 0.0014) in multivariable analysis demonstrating improved discrimination beyond CMR-EI. CONCLUSIONS: CMR derived septal curvature correlates significantly with clinical outcomes including hospital LOS, duration of respiratory support, respiratory support level at hospital discharge, and PH therapy in neonates with BPD and BPD-PH. Further, CMR derived septal curvature demonstrated improved discrimination of need for PH therapy and respiratory support at discharge compared to clinical variables and other CMR indices, supporting septal curvature as a non-invasive marker of PH in this population with potential to guide management strategies.

Implementation of a statewide, multisite fetal tele-echocardiography program: evaluation of more than 1100 fetuses over 9 years.

OBJECTIVES: We sought to describe the implementation and effectiveness of a statewide fetal tele-echocardiography program serving a resource-limited population. STUDY DESIGN: In 2009, our heart center established six satellite clinics for fetal tele-echocardiography around the state. We retrospectively reviewed all fetal tele-echocardiograms performed through 2018. Yearly statewide prenatal detection rates of operable congenital heart disease were queried from the Society of Thoracic Surgeons database. RESULT: In 1164 fetuses, fetal tele-echocardiography identified all types of congenital heart disease, with a sensitivity of 74% and specificity of 97%. For the detection of ductal-dependent congenital heart disease, fetal tele-echocardiography was 100% sensitive and specific. Between 2009 and 2018, annual statewide prenatal detection rates of congenital heart disease requiring heart surgery in the first 6 months of life rose by 159% (17-44%; R2 = 0.88, p < 0.01). CONCLUSIONS: The present study provides a framework for an effective, large-scale fetal tele-echocardiography program.

Cardiac Magnetic Resonance Imaging Evaluation of Neonatal Bronchopulmonary Dysplasia-associated Pulmonary Hypertension.

Rationale: Patients with bronchopulmonary dysplasia (BPD)-associated pulmonary hypertension (PH) have increased morbidity and mortality. Noninvasive assessment relies on echocardiograms (echos), which are technically challenging in this population. Improved assessment could augment decisions regarding PH therapies.Objectives: We hypothesized that neonatal cardiac magnetic resonance imaging (MRI) will correlate with BPD severity and predict short-term clinical outcomes, including need for PH therapies for infants with BPD.Methods: A total of 52 infants (31 severe BPD, 9 moderate BPD, and 12 with either mild or no BPD) were imaged between 39 and 47 weeks postmenstrual age on a neonatal-sized, neonatal ICU-sited 1.5-T magnetic resonance (MR) scanner. MR left ventricular eccentricity index (EI), main pulmonary artery-to-aorta (PA/AO) diameter ratio, and pulmonary arterial blood flow were determined. Echos obtained for clinical indications were reviewed. MRI and echo indices were compared with BPD severity and clinical outcomes, including length of stay (LOS), duration of respiratory support, respiratory support at discharge, and PH therapy.Measurements and Main Results: PA/AO ratio increased with BPD severity. Increased PA/AO ratio, MR-EI, and echo-EIs were associated with increased LOS and duration of respiratory support. No correlation was seen between pulmonary arterial blood flow and BPD outcomes. Controlling for gestational age, birth weight, and BPD severity, MR-EI was associated with LOS and duration of respiratory support. Increased PA/AO ratio and MR-EI were associated with PH therapy during hospitalization and at discharge.Conclusions: MRI can provide important image-based measures of cardiac morphology that relate to disease severity and clinical outcomes in neonates with BPD.

Comparison of Left Ventricular Mass Calculation Methods via Two-Dimensional Echocardiogram in Children, Adolescents, and Young Adults With Systemic Hypertension.

Left ventricular (LV) mass is a major determining tool for myocardial injury in hypertensive patients. Issues with LV mass calculations exist given that there are multiple methods to assess mass, including from the parasternal long axis (PLA), parasternal short axis (PSA), and 2-dimensional (2D) volumetric methods. The aim of this study was to compare the agreement of LV mass calculations using the PLA, PSA, and 2D volumetric methods. This study retrospectively reviewed 200 consecutive, initial echocardiograms for the indication of hypertension. A single reader calculated the LV mass in each patient via the PLA, PSA, and 2D volumetric methods. Percent differences for each study were calculated. LV mass threshold cutoffs of 51 g/m2.7 (cardiac organ injury) and 38.6 g/m2.7 (elevated LV mass) were used to compare categorical differences between the different measurement methods. Paired comparisons demonstrated an absolute mean percent difference of 8.46% to 9.41% among the different methods. LV mass calculated by the 2D volumetric method was less compared with PLA and PSA methods (31.64 vs 33.90 vs 35.51 g/m2.7; p < 0.0001). Fewer patients were classified as having cardiac target organ injury or elevated LV mass via 2D volumetric calculation, compared with PLA and PSA methods (p = 0.02 and p = 0.03, respectively). In conclusion, there is a small but important difference in LV mass calculations for patients with hypertension. These results emphasize the need for consistency within echocardiography laboratories as surveillance studies are common in this patient population.

Short-Axis Diastolic Ventricular Area Ratio as a New Index in Screening Patients with Repaired Tetralogy of Fallot.

Right ventricular (RV) end-diastolic volume measured by cardiovascular magnetic resonance imaging (CMR) is a criterion for pulmonary valve replacement in patients with tetralogy of Fallot (TOF). We sought to determine if the ratio of echocardiographic, short-axis RV-to-left ventricular (LV) end-diastolic areas (EDA) could be used to predict RV volume on CMR. We retrospectively reviewed the echocardiograms of all patients with repaired TOF who underwent CMR at our institution from 2011 to 2015 and also had an echocardiogram within 6 months of the CMR. The short-axis RV and LV EDAs were measured and the ratio of the two was calculated. Results were compared with CMR RV end-diastolic volume index (RVEDVi) and RV:LV end-diastolic volume ratio. The sensitivity and specificity values predicting RV volumes > 150 ml/m2 were calculated. Fifty-eight studies met inclusion criteria. There were 47 studies with RVEDVi < 150 ml/m2 and 11 with RVEDVi > 150 ml/m2. RV:LV EDA and CMR RV:LV end-diastolic volume ratio correlated strongly (r = 0.76, p < 0.0001). An RV:LV EDA ≥ 1.57 had a 90% sensitivity to predict RVEDVi > 150 ml/m2 (area under the curve = 0.74, 95% CI 1.5-27.9; p = 0.012). An RV:LV EDA ≥ 1.88 had an 81% specificity to detect RV volume index > 150 ml/m2. Short-axis RV:LV EDA correlates well with an increased RVEDVi as measured by CMR. This new and simple measure can be used to predict optimal timing for CMR in anticipation of pulmonary valve replacement in repaired TOF.

Characteristics of Non-postoperative Pediatric Pericardial Effusion: A Multicenter Retrospective Cohort Study from the Pediatric Health Information System (PHIS).

Little is known about the causes and risks of non-postoperative pericardial effusion (PCE) in pediatric patients. We sought to assess the diagnoses most frequently associated with admissions for PCE, and to determine if certain conditions were associated with higher in-hospital mortality and rates of readmission. Nationally distributed data from 44 pediatric hospitals in the 2004-2015 Pediatric Health Information System database were used to identify patients with hospital admissions for International Classification of Disease, Ninth Revision (ICD-9) codes for PCE and/or cardiac tamponade. Children with congenital heart disease were excluded. ICD-9 codes for conditions associated with PCE were grouped into eight categories: neoplastic, renal, autoimmune/inflammatory, pneumonia, viral, bacterial, hypothyroidism, and idiopathic. Multivariable models were used to evaluate odds of in-hospital mortality and readmission within 30 and 90 days. There were 9902 patients who met inclusion criteria. Total in-hospital mortality was 8.2% (n = 813); of those without a neoplastic diagnosis, mortality was 6.5% (n = 493/7543). Idiopathic PCE accounted for the most admissions (36%), followed by neoplasms (24%), pneumonia (20%), and autoimmune/inflammatory disease (19%). In multivariable models, odds of death were highest for neoplasms (adjusted odds ratio 3.83, p < 0.001) and renal disease (adjusted odds ratio 2.86, p < 0.001). Children with a neoplasm, renal disease, and those undergoing pericardiocentesis had the highest rates of readmission at 30 and 90 days. Children admitted with non-postoperative PCE have multiple associated conditions. Neoplasm and renal disease in the setting of PCE are associated with the highest odds of in-hospital mortality among concomitant conditions; children with a neoplasm, renal disease, and those undergoing pericardiocentesis have the highest odds of readmission.

Appropriateness and diagnostic yield of inpatient pediatric echocardiograms.

OBJECTIVE: Multiple reports have shown echocardiograms for certain indications are neither cost-effective nor of high diagnostic yield. Given the ease with which tests can be obtained at a tertiary academic children's hospital, our aims were to: (1) determine the diagnostic yield of inpatient studies by in-hospital location; (2) evaluate inpatient echocardiograms to determine indications and level of appropriateness; and (3) evaluate the frequency of cardiology involvement prior to those echocardiograms. DESIGN: All initial inpatient echocardiograms interpreted at our institution from February 2009 to December 2014 were reviewed retrospectively. Patient location was grouped as pediatric intensive care (PICU), emergency department (ED), and general floor. RESULTS: There were 727 first-time inpatient echocardiograms that met inclusion criteria. Pathology was identified in 25% of the study echocardiograms, with 11% of all studies demonstrating pathology that could alter patient management (moderate or severe pathology). The studies performed in the PICU and ED had more severe pathology compared with those from the general floor (P < .001, .003; respectively). Few echocardiograms were performed for rarely appropriate indications on the general floor (7%) and PICU (2.2%). Over 75% of general floor echocardiograms performed for a pathologic murmur yielded normal or incidental findings. Cardiology consultation was documented in only 7.5% of general floor studies. CONCLUSION: The diagnostic yield of inpatient, first-time pediatric echocardiograms is relatively low. The majority of studies that identified pathology were performed on patients located in higher acuity units. General floor echocardiograms for murmurs had a low diagnostic yield, raising the question of cardiology consultation versus direct echocardiogram ordering for subjective physical exam signs.

Biologic variability and correlation of platelet function testing in healthy dogs.

BACKGROUND: Platelet function tests are influenced by biologic variability, including inter-individual (CVG ) and intra-individual (CVI ), as well as analytic (CVA ) variability. Variability in canine platelet function testing is unknown, but if excessive, would make it difficult to interpret serial results. Additionally, the correlation between platelet function tests is poor in people, but not well described in dogs. OBJECTIVES: The aims were to: (1) identify the effect of variation in preanalytic factors (venipuncture, elapsed time until analysis) on platelet function tests; (2) calculate analytic and biologic variability of adenosine diphosphate (ADP) and arachidonic acid (AA)-induced thromboelastograph platelet mapping (TEG-PM), ADP-, AA-, and collagen-induced whole blood platelet aggregometry (WBA), and collagen/ADP and collagen/epinephrine platelet function analysis (PFA-CADP, PFA-CEPI); and (3) determine the correlation between these variables. METHODS: In this prospective observational trial, platelet function was measured once every 7 days, for 4 consecutive weeks, in 9 healthy dogs. In addition, CBC, TEG-PM, WBA, and PFA were performed. RESULTS: Overall coefficients of variability ranged from 13.3% to 87.8% for the platelet function tests. Biologic variability was highest for AA-induced maximum amplitude generated during TEG-PM (MAAA; CVG = 95.3%, CVI = 60.8%). Use of population-based reference intervals (RI) was determined appropriate only for PFA-CADP (index of individuality = 10.7). There was poor correlation between most platelet function tests. CONCLUSIONS: Use of population-based RI appears inappropriate for most platelet function tests, and tests poorly correlate with one another. Future studies on biologic variability and correlation of platelet function tests should be performed in dogs with platelet dysfunction and those treated with antiplatelet therapy.

Maternal anti-platelet ß3 integrins impair angiogenesis and cause intracranial hemorrhage.

Fetal and neonatal alloimmune thrombocytopenia (FNAIT) is a life-threatening disease in which intracranial hemorrhage (ICH) is the major risk. Although thrombocytopenia, which is caused by maternal antibodies against ß3 integrin and occasionally by maternal antibodies against other platelet antigens, such as glycoprotein GPIbα, has long been assumed to be the cause of bleeding, the mechanism of ICH has not been adequately explored. Utilizing murine models of FNAIT and a high-frequency ultrasound imaging system, we found that ICH only occurred in fetuses and neonates with anti-ß3 integrin-mediated, but not anti-GPIbα-mediated, FNAIT, despite similar thrombocytopenia in both groups. Only anti-ß3 integrin-mediated FNAIT reduced brain and retina vessel density, impaired angiogenic signaling, and increased endothelial cell apoptosis, all of which were abrogated by maternal administration of intravenous immunoglobulin (IVIG). ICH and impairment of retinal angiogenesis were further reproduced in neonates by injection of anti-ß3 integrin, but not anti-GPIbα antisera. Utilizing cultured human endothelial cells, we found that cell proliferation, network formation, and AKT phosphorylation were inhibited only by murine anti-ß3 integrin antisera and human anti-HPA-1a IgG purified from mothers with FNAIT children. Our data suggest that fetal hemostasis is distinct and that impairment of angiogenesis rather than thrombocytopenia likely causes FNAIT-associated ICH. Additionally, our results indicate that maternal IVIG therapy can effectively prevent this devastating disorder.

The effect of modified ultrafiltration on angiopoietins in pediatric cardiothoracic operations.

BACKGROUND: Cardiopulmonary bypass subjects patients' blood to hemodilution and nonphysiologic conditions, resulting in a systemic inflammatory response. Modified ultrafiltration (MUF) counteracts hemodilution and has also been postulated to improve outcomes by proinflammatory cytokine removal. The objective of this study was to investigate whether the benefits of MUF include the removal of proinflammatory mediators, such as angiopoietin-2 (angpt-2). We hypothesize that some of the clinical benefits of MUF are related to the preferential removal of angpt-2. METHODS: We performed a prospective cohort study in children 18 years old or younger undergoing cardiopulmonary bypass. Serum samples were obtained from each patient preoperatively, after cardiopulmonary bypass, and on intensive care unit admission. A fluid sample from the MUF effluent was also analyzed. Angpt-1, angpt-2, interleukin-8, and interleukin-10 levels were determined by enzyme-linked immunosorbent assay. RESULTS: Thirty-one patients were enrolled. Angpt-1 levels significantly decreased across all time points (p<0.01). Angpt-2 concentrations were significantly elevated at intensive care unit admission when compared with both preoperative and post-cardiopulmonary bypass levels (p<0.01). The angpt-2:1 ratio significantly increased after cardiopulmonary bypass to intensive care unit admission (p<0.01). There was no significant difference between the angpt-2 or angpt-1 percentage of extraction within MUF effluent. Interleukin-8 and interleukin-10 significantly increased from preoperative to intensive care unit admission (both p<0.01). CONCLUSIONS: The results of this study demonstrate that MUF removes both proinflammatory and antiinflammatory mediators equally. This study suggests that the clinical benefits of MUF cannot be attributed to the removal of larger quantities of proinflammatory mediators such as angpt-2 and interleukin-8.