Use of VA ECMO and percutaneous palliation of ductal dependent coarctation in a neonate with trisomy 21 and COVID-19 pneumonia

We present a case of a neonate with trisomy 21, ductal-dependent aortic coarctation, and severe respiratory failure secondary to coronavirus disease 2019 (COVID-19) pneumonia. The neonate was managed with venoarterial extracorporeal membrane oxygenation (VA ECMO), palliative stenting of the coarctation, and a vascular plug occlusion of a large patent ductus arteriosus. The patient was successfully weaned off extracorporeal membrane oxygenation (ECMO). The patient is currently awaiting a definitive surgical repair in the near future.     

Cardiac function in adolescents and young adults with 22q11.2 deletion syndrome without congenital heart disease

BackgroundDiagnosis and treatment of 22q11.2 deletion syndrome (22q11.2DS) have led to improved life expectancy and achievement of adulthood. Limited data on long-term outcomes reported an increased risk of premature death for cardiovascular causes, even without congenital heart disease (CHD). The aim of this study was to assess the cardiac function in adolescents and young adults with 22q11.2DS without CHDs.MethodsA total of 32 patients (20M, 12F; mean age 26.00 ± 8.08 years) and a healthy control group underwent transthoracic echocardiography, including Tissue Doppler Imaging (TDI) and 2-dimensional Speckle Tracking Echocardiography (2D-STE).ResultsCompared to controls, 22q11.2DS patients showed a significant increase of the left ventricle (LV) diastolic and systolic diameters (p = 0.029 and p = 0.035 respectively), interventricular septum thickness (p = 0.005), LV mass index (p < 0.001) and aortic root size (p < 0.001). 2D-STE analysis revealed a significant reduction of LV global longitudinal strain (p < 0.001) in 22q11.2DS than controls. Moreover, several LV diastolic parameters were significantly different between groups.ConclusionsOur results suggest that an echocardiographic follow-up in 22q11.2DS patients without CHDs can help to identify subclinical impairment of the LV and evaluate a potential progression of aortic root dilation over time, improving outcomes, reducing long-term complications and allowing for a better prognosis.     

Percutaneous balloon aortic valvuloplasty in the treatment of congenital valvu lar aortic stenosis in children

Objective To assess the effect of the balloon valvuloplasty for congenital valvular aortic stenosis (AS) in children.Methods A total of 27 (mean age 6.09 years) children with AS accepted the treatment of percutaneous balloon aortic valvuloplasty (PBAV).The ratios of balloon/valve were 0.95±0.08 for 19 cases of typical AS and 1.00±0.11 for 8 cases of hyp oplastic AS.The patients were evaluated by the gradients across aotic valves i n pre- and post-PBAV and by echocardiogram during the follow-up period.Results Fifteen of 19 （78.9%）cases of typical AS had a better outcome and the gradien t of the remaining 4 cases (26.7%) had increased after follow-up (ΔP&gt;50 mm Hg).Four of 8 (50.0%) cases of hypoplastic AS had satisfactory responses and the gradient of the remaining 3 cases (75.0%) rose.There was no moderate to s evere aortic insufficiency (AI). Conclusion The balloon aortic valvuloplasty provides safe and significant hemodynamic and c linical improvement in pediatric patients.The outcome of PBAV for typical AS is better than for hypoplastic AS.     

黄体酮对兔离体主动脉平滑肌张力的影响

目的　观察黄体酮对KCl去极化引起的兔离体主动脉肌条收缩作用的影响 ,并探讨其作用与内皮细胞的关系。方法　制备家兔离体主动脉平滑肌条 ,置于灌流肌槽中 ,记录肌条的张力变化。结果　黄体酮 (5、5 0和 10 0 μmol·L- 1)使KCl量效曲线明显右移 ,最大反应压低 ,KCl的EC50 由对照 (36.4± 19.7)mmol·L- 1依次变为 (4 0 .3± 19.6)、(4 3.4± 2 0 .9)和 (5 9.0± 2 0 .1)mmol·L- 1(r =0 .94 ,P <0 .0 5 ) ;83.3μmol·L- 1黄体酮使KCl 2 5 .1mmol·L- 1预收缩胸主动脉肌条明显舒张 (P <0 .0 0 1) ;去内皮后 ,此舒张作用明显减弱。结论　黄体酮可使兔胸主动脉血管平滑肌条舒张 ,其作用可能是通过抑制血管平滑肌细胞膜上的电压依赖性钙通道 ,并与内皮细胞存在有关     

二尖瓣成形测瓣器的研制和临床应用

目的为在二尖瓣成形术中准确迅速判断瓣环和瓣叶病损的部位及程度,提高二尖瓣成形术的成功率。方法解剖测量30例国人正常新鲜心脏的二尖瓣,术中观察二尖瓣病理变化特点后研制了一种新型二尖瓣成形测瓣器。结果用测瓣器行二尖瓣成形术35例,成形手术时间由原来的(57±11)min减少到(35±15)min,手术死亡率由11％下降到3．3％。结论使用此种测瓣器可使二尖瓣成形术省时、准确,成功率明显提高。     

经皮球囊二尖瓣成形术治疗风湿性二尖瓣狭窄的体会

目的：初步探讨经皮球囊二尖瓣成形术（PBMV）技术操作中的几个问题及处理对策。方法：采用国产单球囊导管对4例风湿性心脏病二尖瓣狭窄患进行PBMV。结果：4例患均获成功,血流动力学均明显好转。结论：PBMV技术操作中有关几个问题的处理对策是提高手术效果有效可行的方法。     

Ionic and haemodynamic changes influence the release of the excitatory amino acid glutamate in the posterior hypothalamus

The push-pull technique was used to investigate the release of the excitatory amino acid glutamate in the posterior hypothalamic area of the conscious rat. The hypothalamus was superfused through the pushpull cannula with artificial cerebrospinal fluid (CSF), and the superfusate was collected in time periods of 10 min when ionic conditions in the CSF were changed, or in short periods of 3 min when blood pressure changes were evoked. The mean glutamate release rate was 2.8 + 0.7 pmol/min. Depolarization by hypothalamic superfusion with CSF containing 50 mM K⁺ enhanced the release of glutamate in the presence of Ca²⁺. The K⁺-induced release was attenuated by 40% when the hypothalamus was superfused with Ca²⁺-free CSF. Replacement of Ca²⁺ by Mg²⁺ abolished the K⁺-induced release of glutamate. Hypovolaemia elicited by haemorrhage enhanced the release rate of glutamate. Similarly, a hypotension elicited by i.v. injection of chlorisondamine (3 mg/kg) led to a pronounced and permanent enhancement in glutamate release. The effects of hypovolaemia and chlorisondamine on glutamate release were abolished in aortic denervated rats, indicating that this response is due to a decrease of impulse generation in baroreceptors. A hypovolaemia elicited by blood infusion did not affect the release of glutamate. Similarly, a pronounced pressor response to phenylephrine (15 /kg per minute) infused intravenously for 9 min was ineffective.The results show that the K⁺-induced release of glutamate in the hypothalamus is dependent on the presence of Ca²⁺. The increase in glutamate release rate by hypovolaemia or chlorisondamine suggests that the glutamatergic neurons in the posterior hypothalamic area respond to unloading of aortic baroreceptors and possess a counteracting, hypertensive function.     

Finite Element Model Determination of Correction Factors Used for Measurement of Aortic Diameter via Conductance

Traditional methods for estimating the slope and offset volume V _P for determining real-time chamber volume by the conductance catheter technique are not suited to measurements made in the aorta due to the relatively low resistivity of the aortic wall. We developed three distinct three-dimensional finite element models of the conductance catheter and surrounding tissues in order to predict and V _P and to examine the nature of the electric field near the aortic wall. A heterogeneous isotropic model of the catheter, aorta and surrounding tissues accurately predicted the values of and V _P . A homogeneous anisotropic model was developed to examine the effects of anisotropy of blood and the layers of the aortic wall on measured values of resistance, and V _P . This model demonstrated that anisotropy of blood and aortic wall tissue can increase the values of both and V _P . Finally, a three-dimensional homogeneous isotropic rectangular model allowed examination of the effects of catheter position. This model showed small effects of catheter position on measured resistance (9.7% increase) and larger effects on (21.2% decrease) and V _P (41.9% increase). We conclude the following: the FEA models may lead to accurate estimate values of and V _P in vivo. The unique anisotropic conductive properties of the layers of the aortic wall contribute to the high observed values of and V _P in the aorta. Finally, catheter position has a proportionately greater effect on and V _P than on measured resistance. The results of this study should assist in the determination of aortic mechanical properties using conductance catheter measurements of vessel dimension. © 1999 Biomedical Engineering Society. PAC99: 8719Nn, 8719Rr, 8719Uv, 0270Dh, 8717Aa     

经皮球囊二尖瓣成形术10年临床经验

目的：旨在研究本院４００ 例经皮球囊二尖瓣成形术１０ 年的临床经验。　方法：采用改良的Ｉｎｏｕｅ 方法。　结果：经皮球囊二尖瓣成形术即刻成功率９８．３％ （３４４／３５０）,术后二尖瓣面积明显增加,达（１．１１±０．２９）～（２．１９±０．４０）ｃｍ ２。１０５ 例随访９个月～８ 年６ 个月,二尖瓣再狭窄率为１１．４％ （１２／１０５）,死亡率为２．９％ （３／１０５）,二尖瓣置换术为３．８％ （４／１０５）。　结论：经皮球囊二尖瓣成形术近、远期疗效均很好