Background
The ratio of the transverse diameter of the main pulmonary artery (MPA) to ascending aorta as determined at multi-detector CT is a tool that can be used to assess the pulmonary arterial ...size in cases of pulmonary arterial hypertension in children.
Objective
To establish a ratio of MPA to ascending aorta diameter using multi-detector CT imaging suggestive of pulmonary arterial hypertension in children. We hypothesize that a defined ratio of MPA to ascending aorta is identifiable on multi-detector CT and that higher ratios can be used to reliably diagnose the presence of pulmonary arterial hypertension in children.
Materials and methods
We calculated the multi-detector CT ratio of MPA to ascending aorta diameter in 44 children with documented pulmonary arterial hypertension by right heart catheterization and in 44 age- and gender-matched control children with no predisposing factors for pulmonary arterial hypertension. We compared this multi-detector-CT-determined ratio with the MPA pressure in the study group, as well as with the ratio of MPA to ascending aorta in the control group. A threshold ratio value was calculated to accurately identify children with pulmonary arterial hypertension.
Results
Children with documented primary pulmonary arterial hypertension have a significantly higher ratio of MPA to ascending aorta (1.46) than children without pulmonary arterial hypertension (1.11). A ratio of 1.3 carries a positive likelihood of 34 and a positive predictive value of 97% for the diagnosis of pulmonary arterial hypertension.
Conclusion
The pulmonary arteries were larger in children with pulmonary arterial hypertension than in a control group of normal children. A CT-measured ratio of MPA to ascending aorta of 1.3 should raise the suspicion of pulmonary arterial hypertension in children.
The objective of this study was to investigate the systolic to diastolic duration ratio (S:D ratio) in children with pulmonary arterial hypertension (PAH) and its association with right ventricular ...(RV) performance, hemodynamics, 6-minute walk test, clinical outcomes, and survival. We reviewed 503 serial echocardiograms in 47 children with PAH (mean pulmonary artery pressure ≥25 mm Hg) and compared the S:D ratio, assessed from Doppler flow of tricuspid valve regurgitation, to that in 47 age-matched controls. We reviewed echocardiograms, catheterization data, 6-minute walk tests, clinical data, lung transplantation, and death and used univariate linear regression models with a maximum likelihood algorithm for parameter estimation to investigate associations between S:D ratio and RV function, hemodynamics, functional capacity, and clinical outcomes. The S:D ratio was significantly higher in patients than in controls (1.38 ± 0.61 vs 0.72 ± 0.16, p <0.001). A higher S:D ratio was associated with worse echocardiographic RV fractional area of change, worse catheterization hemodynamics, shorter 6-minute walk distance, and worse clinical outcomes independent of pulmonary resistance or pressures. An increase of 0.1 in the S:D ratio was associated with a 13% increase in yearly risk for lung transplantation or death (hazard ratio 1.13, p <0.001). An S:D ratio 1.00 to 1.40 was associated with a moderate risk and an S:D ratio >1.40 was associated with a high risk of a negative outcome. In conclusion, in children with PAH, an increased S:D ratio is temporally associated with worse RV function, hemodynamics, exercise capability, clinical status, and survival.
Biventricular assist device (BiVAD) support was a strong predictor of early mortality in the Berlin Heart EXCOR Pediatric investigational device exemption (IDE) study (Assess Safety and Probable ...Benefit of the EXCOR Pediatric Ventricular Assist Device VAD). In adults, it has been identified that 5% to 10% of the VAD population is benefited by BiVAD support over left ventricular assist device (LVAD) support. An analysis of the Berlin Heart study cohort was performed to characterize patients supported with BiVAD, examine risk factors of mortality in this group, and identify subsets of patients in whom BiVAD is associated with survival.
All EXCOR Pediatric devices (Berlin Heart, Inc, The Woodlands, TX) placed in North America between May 2007 and December 2010 comprised the study cohort of 204 patients (128 63% LVADs and 76 37% BiVADs). The following patient cohorts were analyzed to determine the effect of BiVAD use on survival: Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profile 1 patients, patients with abnormal bilirubin levels, patients who received previous extracorporeal membrane oxygenation (ECMO), and patients with a 10-mL pump size.
There were more patients with BiVADs in INTERMACS profile 1 (63% compared with 46%; p = 0.018). The incidence of major bleeding, neurologic and renal dysfunction, and infection was similar between BiVAD and LVAD groups. White race, abnormal glomerular filtration rate (GFR), sites with experience of less than 5 implantations, and use of 10-mL pumps were predictors of mortality in patients who received BiVADs. BiVADs were not associated with improved survival in any patient cohort; however, they were associated with increased mortality in patients who had undergone ECMO before receiving a VAD.
BiVAD support was not associated with improved survival in any identified subset of patients. Although not randomized, these results (which were corrected for multiple possible risk factors) suggest that some children supported with BiVADs might have done better with LVADs alone. Further prospective studies will be needed to identify patient cohorts that will be better served with BIVAD support.
Background
Secondary pulmonary lymphangiectasia is a complication of congenital heart disease that results from chronic pulmonary venous obstruction.
Objectives
We aimed to evaluate the performance ...of chest ultrasound (US) in diagnosing secondary pulmonary lymphangiectasia and to review the clinical course of children with secondary pulmonary lymphangiectasia.
Materials and methods
Chest US was performed on 26 children with hypoplastic left heart syndrome, total anomalous pulmonary venous connection or cor triatriatum in a prospective observational study. Thirteen children had pulmonary venous obstruction (62% male; median age: 17 days old, range: 1–430 days old) and 13 children did not have obstruction (62% male; median age: 72 days old, range: 4–333 days old). US features of secondary pulmonary lymphangiectasia were documented and diagnostic performance was determined. Clinical course of patients with secondary pulmonary lymphangiectasia was reviewed.
Results
Eleven of 13 (84.6%) patients in the obstructed group had a clinical and/or biopsy diagnosis of secondary pulmonary lymphangiectasia. Statistically significant chest US criteria for diagnosis were presence of irregular lung surface (likelihood ratio LR 6.8, 95% confidence interval CI 1.9–25.1), subpleural cystic appearing structures (LR 3.6, 95% CI 1.2–10.7), and combination of subpleural cystic appearing structures and surface irregularity together (LR 10.9, 95% CI 1.6–75.0). Seven of 11 (63.6%) patients with secondary pulmonary lymphangiectasia died during follow-up, the majority due to cardiopulmonary failure or complications.
Conclusion
Chest US is an accurate and reproducible bedside method for diagnosing secondary pulmonary lymphangiectasia in patients with pulmonary venous obstruction. These patients may have worse prognoses.
To compare therapeutic hypothermia (TH) treatment of term and near-term neonates with hypoxic-ischemic encephalopathy (HIE) between neonatal units.
Population-based, retrospective analysis of TH ...initiation and maintenance, and of diagnostic imaging. The comparison between units was based on crude data analysis, indirect standardization, and adjusted logistic regression.
TH was provided to 570 neonates with HIE between 2011 and 2018 in 10 Swiss units. We excluded 121 off-protocol cooled neonates to avoid selection bias. Of the remaining 449 neonates, the outcome was favorable to international benchmarks, but there were large unit-to-unit variations in baseline perinatal data and TH management. A total of 5% neonates did not reach target temperature within 7 h (3-10% between units), and 29% experienced over- or undercooling (0-38%).
Although the neonates had favorable short-term outcomes, areas for improvement remain for Swiss units in both process and outcome measures.
A proportion of patients with pulmonary arterial hypertension associated with congenital heart disease (PAH-CHD) do not fit in the current classification. We aimed to analyse the applicability of an ...adapted clinical classification of PAH-CHD to pediatric patients using the TOPP-1 registry (Tracking Outcomes and Practice in Pediatric Pulmonary Hypertension) and focus on atrial septal defects (ASD) and transposition of the great arteries (TGA).
Hemodynamic and clinical data of all patients with PAH-CHD in the TOPP cohort were reviewed. Patients were classified according to predefined ABCDE categories (A: Eisenmenger syndrome, B: left-to-right shunt, C: coincidental defects, including all ASDs, D: corrected CHD, E: TGA), or as complex CHD (group 5), by 2 independent investigators. In case of disagreement, a third reviewer could either settle a final decision, or the patient was deemed not classifiable. Survival curves were calculated for each group and compared to idiopathic PAH patients of the registry. A total of 223 out of 531 patients in the registry had PAH-CHD, and 193 were categorized to the following groups: A 39(20%), B 27(14%), C 62(32%) including 43 ASDs, D 58(30%), E 7(4%), whereas 6 patients were categorized as group 5, and 10 patients were unable to be classified. No survival difference could be demonstrated between the groups.
This modified classification seems to be more applicable to pediatric PAH-CHD patients than the previous classification, but some patients with PAH-CHD who never had a shunt remain unclassifiable. The role of ASD in pediatric PH should be reconsidered.
Objectives Chronic right ventricular (RV) pressure overload results in pathologic RV hypertrophy and diminished RV function. Although aortic constriction has been shown to improve systolic function ...in acute RV failure, its effect on RV responses to chronic pressure overload is unknown. Methods Adjustable vascular banding devices were placed on the main pulmonary artery and descending aorta. In 5 animals (sham group), neither band was inflated. In 9 animals (PAB group), only the pulmonary arterial band was inflated, with adjustments on a weekly basis to generate systemic or suprasystemic RV pressure at 28 days. In 9 animals, both pulmonary arterial and aortic devices were inflated (PAB + AO group), the pulmonary arterial band as for the PAB group and the aortic band adjusted to increase proximal systolic blood pressure by approximately 20 mm Hg. Effects on the functional performance were assessed 5 weeks after surgery by conductance catheters, followed by histologic and molecular assessment. Results Contractile performance was significantly improved in the PAB + AO group versus the PAB group for both ventricles. Relative to sham-operated animals, both banding groups showed significant differences in myocardial histologic and molecular responses. Relative to the PAB group, the PAB + AO group showed significantly decreased RV cardiomyocyte diameter, decreased RV collagen content, and reduced RV expression of endothelin receptor type B, matrix metalloproteinase 9, and transforming growth factor β genes. Conclusions Aortic constriction in an experimental model of chronic RV pressure overload not only resulted in improved biventricular systolic function but also improved myocardial remodeling. These data suggest that chronically increased left ventricular afterload leads to a more physiologically hypertrophic response in the pressure-overloaded RV.
Objectives The lack of accurate measurement of hemodynamics and oxygen transport has limited our understanding of Norwood physiology and postoperative management. We used measured oxygen consumption ...to characterize hemodynamics and oxygen transport after the classic Norwood procedure. Methods Fourteen neonates had continuous respiratory mass spectrometry to measure oxygen consumption (VO2 ). Arterial, superior vena caval, and pulmonary venous saturations were measured at 2- to 4-hour intervals for 72 hours postoperatively. Systemic (Qs) and pulmonary (Qp) blood flows, systemic vascular resistance (SVR) and pulmonary vascular resistance inclusive of the Blalock–Taussig shunt (BT-PVR), systemic oxygen delivery (DO2 ), and the oxygen extraction ratio (ERO2 ) were calculated. Results Qs and DO2 were low during the first 12 hours (1.8 ± 0.6 L · min−1 · m−2 and 281 ± 86 mL · min−1 · m−2 at the 12th hour, respectively) and increased over the study period ( P < .05 for both). VO2 decreased markedly during the first 24 hours (101 ± 26 to 86 ± 16 mL · min−1 · m−2 , P < .0001). Consequently, ERO2 decreased significantly over the study, most rapidly during the first 24 hours (0.44 ± 0.11 to 0.28 ± 0.09, P < .0001). There was a close correlation of DO2 to SVR and to Qs ( P < .0001 for both). There was no correlation of DO2 to BT-PVR ( P = .14) or to Qp ( P = .67). DO2 was closely correlated with hemoglobin value ( P < .0001), weakly correlated with Pa o2 ( P = .0002), and not correlated with arterial oxygen saturation ( P = .32). Conclusions There is wide variability of hemodynamics and oxygen transport after the Norwood procedure. The decrease in VO2 during the first 24 hours is the main contributor to improving the balance of oxygen transport. DO2 is most closely correlated to SVR and hemoglobin and weakly correlated to Pa o2 . It is not correlated to Qp. Postoperative management strategies to decrease VO2 and maintain a high hemoglobin level and a low SVR appear to be rational.
The Berlin Heart EXCOR Pediatric Ventricular Assist Device (BH) was approved for use in the United States in December 2011, based on a prospective investigational device exemption (IDE) trial. Strict ...exclusion criteria for the trial selected a low-risk "ideal" cohort. We sought to determine whether postapproval usage of the BH in a "real world" cohort of recipients would result in similar outcomes. Preimplant diagnostic information was collected for all patients. Efficacy was evaluated by comparison of all children (efficacy group, n = 247) implanted between FDA approval and April 2015 to those in the IDE trial (IDE, n = 48), with regard to achievement of one of four end-states: transplanted, successful weaning, death/unsuccessful weaning, or still-on-device. Safety outcomes were compared between IDE patients and a subset of postapproval patients (safety group, n = 39) for whom adjudicated adverse events were tracked in a regulator-mandated dataset. Diagnostic categories were similar between groups: IDE (congenital 19%, dilated cardiomyopathy/myocarditis/other 81%) versus Efficacy Group (congenital 24%, dilated cardiomyopathy/myocarditis/other 75%). Patients in the IDE cohort were larger (median 14.8 kg, range 3.6-58.1 kg vs. 10.7 kg, 2.9-112.0 kg, p = 0.02). More IDE patients were successfully supported than in the efficacy group cohort (90% vs. 77%, p = 0.05). Proportions with bleeding and stroke were similar between the IDE and safety group cohorts (46% vs. 41%, p = 0.65; 29% vs. 33%, p = 0.68, respectively). With usage of the BH in a less-ideal population, rates of bridge to transplant and weaning have declined slightly, but remain encouragingly high. Bleeding and neurologic event rates have not increased.
Abstract The updated American Heart Association/American Stroke Association guidelines include recommendation for thrombectomy in certain adult stroke cases. The safety and efficacy of thrombectomy ...in children are unknown. An 8-year-old girl experienced acute stroke symptoms on two occasions while therapeutically anticoagulated on Novalung. Computed tomography scans showed proximal vessel thrombi, which were retrieved using a Trevo device without hemorrhagic complications. Postprocedural assessment found respective decreases in the National Institutes of Health Stroke Scale score from 10 to 4 and 12 to 7. The indications for treatment and early benefits observed in our case are consistent with other pediatric thrombectomy cases reported. However, publication bias and the heterogeneity of reported cases prevent drawing conclusions about the safety and efficacy of thrombectomy in children. Anticipating that updates to adult stroke guidelines would likely incite stroke providers to consider thrombectomy in children, our institution developed guidelines for thrombectomy before the index patient. Establishing institutional guidelines before considering thrombectomy in children may optimize patient safety.
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