Baseline left ventricular ejection fraction associated with symptom improvements in both children and adolescents with postural tachycardia syndrome under metoprolol therapy / 中华医学杂志(英文版)

BACKGROUND@#Postural tachycardia syndrome (POTS) is a common childhood disease that seriously affects the patient's physical and mental health. This study aimed to investigate whether pre-treatment baseline left ventricular ejection fraction (LVEF) and left ventricular fractional shortening (LVFS) values were associated with symptom improvement after metoprolol therapy for children and adolescents with POTS.@*METHODS@#This retrospective study evaluated 51 children and adolescents with POTS who received metoprolol therapy at the Peking University First Hospital between November 2010 and July 2019. All patients had completed a standing test or basic head-up tilt test and cardiac echocardiography before treatment. Treatment response was evaluated 3 months after starting metoprolol therapy. The pre-treatment baseline LVEF and LVFS values were evaluated for correlations with decreases in the symptom score after treatment (ΔSS). Multivariable analysis was performed using factors with a P value of  0.050). However, responders had significantly higher baseline LVEF (71.09% ± 4.44% vs. 67.17% ± 4.88%, t = -2.789, P = 0.008) and LVFS values (40.00 [38.00, 42.00]% vs. 36.79% ± 4.11%, Z = -2.542, P = 0.010) than the non-responders. The baseline LVEF and LVFS were positively correlated with ΔSS (r = 0.378, P = 0.006; r = 0.363, P = 0.009), respectively. Logistic regression analysis revealed that LVEF was independently associated with the response to metoprolol therapy in children and adolescents with POTS (odds ratio: 1.201, 95% confidence interval: 1.039-1.387, P = 0.013).@*CONCLUSIONS@#Pre-treatment baseline LVEF was associated with symptom improvement after metoprolol treatment for children and adolescents with POTS.

Increased Endogenous Sulfur Dioxide Involved in the Pathogenesis of Postural Tachycardia Syndrome in Children: A Case-Control Study / 中华医学杂志(英文版)

<p><b>Background</b>The pathogenesis of postural tachycardia syndrome (POTS) remains unclear. This study aimed to explore the changes and significance of sulfur dioxide (SO) in patients with POTS.</p><p><b>Methods</b>The study included 31 children with POTS and 27 healthy children from Peking University First Hospital between December 2013 and October 2015. A detailed medical history, physical examination results, and demographic characteristics were collected. Hemodynamics was recorded and the plasma SOwas determined.</p><p><b>Results</b>The plasma SOwas significantly higher in POTS children compared to healthy children (64.0 ± 20.8 μmol/L vs. 27.2 ± 9.6 μmol/L, respectively, P < 0.05). The symptom scores in POTS were positively correlated with plasma SOlevels (r = 0.398, P < 0.05). In all the study participants, the maximum heart rate (HR) was positively correlated with plasma levels of SO(r = 0.679, P < 0.01). The change in systolic blood pressure from the supine to upright (ΔSBP) in POTS group was smaller than that in the control group (P < 0.05). The ΔSBP was negatively correlated with baseline plasma SOlevels in all participants (r = -0.28, P < 0.05). In the control group, ΔSBP was positively correlated with the plasma levels of SO(r = 0.487, P < 0.01). The change in HR from the supine to upright in POTS was obvious compared to that of the control group. The area under curve was 0.967 (95% confidence interval: 0.928-1.000), and the cutoff value of plasma SOlevel >38.17 μmol/L yielded a sensitivity of 90.3% and a specificity of 92.6% for predicting the diagnosis of POTS.</p><p><b>Conclusions</b>Increased endogenous SOlevels might be involved in the pathogenesis of POTS.</p>

A family-based transmission disequilibrium test of polymorphisms of endothelial nitric oxide synthase gene in children with orthostatic intolerance / 中国当代儿科杂志

<p><b>OBJECTIVE</b>Recent studies have found that the variation of G894T on the region of T786C and 7th exon promoted by endothelial nitric oxide synthase (eNOS) gene is associated with cardiovascular disease. This research explored possible correlations between eNOS gene polymorphisms and orthostatic intolerance (OI) in children through linkage disequilibrium analysis between eNOS genes T786C and G894T and OI.</p><p><b>METHODS</b>PCR, Macrorestriction Map and other molecular biotechnology were used to determine the genotypes of eNOS/T786C and G894T in 60 OI probands and their parents. Correlation analysis and transmission disequilibrium test (TDT) between T786C, G894T and OI were performed.</p><p><b>RESULTS</b>There was linkage disequilibrium of eNOS/T786C and G894T gene polymorphisms in the occurrence of childhood OI (P<0.05).</p><p><b>CONCLUSIONS</b>eNOS genes T786C and G894T may be associated with the pathogenesis of OI.</p>

Influence of Pulmonary Hypertension Induced by Left-to-Right Shunt on Pulmonary Collagen Remodeling / 实用儿科临床杂志

Objective To establish a rat model of pulmonary hypertension induced by left-to-right shunt and explore the influence of high pulmonary blood flow on pulmonary vascular collagen remodeling.Methods Abdominal aorta and inferior vena cava shunting was produced in rats. Pulmonary artery meanpressure (PAMP) of each rat was measured by using a right cardiac catheterization.Pulmonary artery collagen Ⅰ and Ⅲ were detected using immunohistochemisty.Results After 11 weeks of shunting the Qp/Qs was 3.3∶1.0,indicating a large shunt. Pulmonary artery mean pressure was increased as compared with controls[(23.0?0.9) mm Hg vs (15.7? 1.1) mm Hg,P