High-altitude pulmonary edema with absent right pulmonary artery

High-altitude pulmonary edema potentially is fatal. Adults with unilateral absence of a right pulmonary artery are particularly susceptible to high-altitude pulmonary edema. The occurrence of high-altitude pulmonary edema was documented in a child with congenital absence of the right pulmonary artery. Improvement occurred only upon descent to low altitude. Physicians should be aware of this life-threatening condition in children ascending to high altitude, particularly in individuals with unilateral absence of a pulmonary artery.     

肺静脉指数对肺血减少型先天性心脏病肺血管发育的评估

目的 探索能更准确反映肺血管发育及肺血流情况的指标,为外科手术方案的选择提供依据.方法 采用74例肺血减少型先天性心脏病心血管造影序列,测量左右肺动脉及4根肺静脉直径,分别计算Nakata指数,McGoon指数,肺静脉指数(PVI),分别与术后情况进行相关分析.结果 左、右侧肺静脉大小分别与左右肺动脉大小高度相关,左侧肺静脉与左肺动脉远端的相关性为0.73,左侧肺静脉与左肺动脉近端的相关性为0.72,右侧肺静脉与右肺动脉远端的相关性为0.67,右侧肺静脉与右肺动脉近端的相关性为0.71.PVI与术后监护时间,呼吸机维持时间,正性肌力药物用量的相关性分别为-0.51,-0.478和-0.693,均比Nakata指数,McGoon指数明显增高,能更准确的反映整个肺血管的发育情况.右室流出道重建术后无低心排组与低心排组的McGoon指数分别为1.97±0.58与1.36±0.51(t=2.347,P＜0.05),两组Nakata指数分别为(269±124)mm2/m2和(164±106)mm2/m2(t=2.218,P＜0.05),PVI分别为(273±125)mm2/m2和(152±77)mm2/m2(t=2.936,P＜0.01),低心排组肺血管值均明显小于无低心排组.当PVI小于180 mm2/m2时,术后易出现血流动力学不稳定,低心排,甚至死亡.结论 肺动脉、肺静脉发育彼此相关,PVI能更准确反映肺血管发育及肺血流情况的形态学指标,为外科手术方案的选择提供有效依据.     

Nonketotic hyperglycinemia presenting as pulmonary hypertensive vascular disease and fatal pulmonary edema in response to pulmonary vasodilator therapy

The association of pulmonary hypertensive vascular disease with nonketotic hyperglycinemia is rare. We describe 5?infants diagnosed with nonketotic hyperglycinemia, in whom pulmonary hypertensive vascular disease was the?main presenting feature, and who developed severe pulmonary edema in response to pulmonary vasodilators.     

Common pulmonary vein atresia without anomalous pulmonary venous connection

Common pulmonary vein atresia without pulmonary venous connection is a rare form of congenital heart disease. No communication exists between the confluence of the pulmonary veins and the heart or a major systemic vessel. A case diagnosed antemortem is presented. Correct early diagnosis is imperative as surgery may be corrective.     

Tetralogy of Fallot with severe pulmonary valvar stenosis and pulmonary vascular sling (anomalous origin of the left pulmonary artery from the right pulmonary artery)

Summary A patient with the rare combination of tetralogy of Fallot with severe pulmonary valvar stenosis and pulmonary vascular sling is presented. The limitations imposed by pulmonary artery hypoplasia on the display of pulmonary vascular sling by conventional imaging techniques are discussed.     

Congenital pulmonary arteriovenous fistula producing pulmonary arterial steal syndrome

Summary This report describes a congenital pulmonary arterial steal syndrome manifested as cyanosis and acidosis in a newborn. A fistulous connection between the right pulmonary artery and a large, anomalous right common pulmonary vein stole blood from the pulmonary arteries. The anomaly was suspected because of a pericardiac shadow on frontal and lateral chest films, substantiated by M-mode echocardiogram, confirmed at cardiac catheterization with angiocardiography, and analyzed at postmortem examination. Supported in part by a grant from The Rose M. Badgeley Charitable Trust     

Paediatric pulmonary vascular disease

Pulmonary vascular disease comprises any congenital or acquired pathology of the intrinsic pulmonary vessels with the unique feature of pulmonary arteries carrying unsaturated blood and pulmonary veins carrying oxygenated blood. Pulmonary hypertension (PH) ensues when pulmonary vascular disease affects at least 50% of the capillary resistance vessels, i.e. pulmonary pre-acinar and intra-acinar arteries (so-called pre-capillary PH), or when pressure in the pulmonary venous system distal to the capillaries rises above a mean of 15 mmHg (so-called post-capillary PH). PH is defined by a mean pulmonary arterial pressure above 25 mmHg at rest. Vasoconstriction, remodelling and thrombosis of small pulmonary arteries lead to an increase in pulmonary vascular resistance. The consequence is failure of the afterload-intolerant right ventricle. In this review, pulmonary vascular disease in children will be addressed according to the 2003 World Health Organisation (Venice) classification of PH.     

L—精氨酸对高肺血流量所致肺动脉高压的防治作用

目的 探讨L－精氨酸对高肺血流量所致肺动脉高压的防治作用。方法 21只雄性SD大鼠随机分为对照组（n=6)、分流组（n=7)和分流＋L－精氨酸组（n=8)。对分流组和分流＋L－精氨酸组大鼠行腹主动脉－下腔静脉分流术。11周后以右心导管法测定肺动脉平均压（mPAP)。检测右心室／体重（RV／BW）和右心室／左心室＋室间隔（RV/LV S)比值。并且观测肺血管结构的变化。结果 分流组大鼠mPAP、RV／BW及RV/(LV S）比值明显高于对照组（P均＜0．01）,且分流组大鼠肺小血管肌化程度明显增强,肺中、小肌型动脉相对中膜面积及厚度明显增加。而分流＋L－精氨酸组大鼠mPAP、RV／BW及RV／LV＋S比值明显低于分流组（P均＜0．05）,L－精氨酸缓解了肺血管结构重建的形成。结论 L－精氨酸对高肺血流量所致肺血管结构重建及肺动脉高压有重要的调节作用。     

Contribution of pulmonary surfactant with inhaled nitric oxide for treatment of pulmonary hypertension

BACKGROUND: Combined therapy of inhaled nitric oxide (iNO) with pulmonary surfactant replacement was reported to improve oxygenation in patients or animal models of persistent pulmonary hypertension of the newborn with pulmonary surfactant deficiency lung. To evaluate the potential of iNO for the treatment of persistent pulmonary hypertension of the newborn, pulmonary arterial pressure (PAP) was measured during iNO before and after pulmonary surfactant replacement in an animal model of pulmonary hypertension with surfactant deficiency. METHODS: Seven newborn piglets were injected with L-nitro-arginine-methylester to produce an animal model of pulmonary hypertension. After PAP increased, iNO (30 p.p.m.) was introduced. Then iNO was stopped, and animals were subjected to lung lavage with saline. After recording the effect of iNO, all animals then received exogenous pulmonary surfactant installation. After surfactant treatment, iNO was again introduced. RESULTS: Pulmonary arterial pressure and systemic arterial pressure were increased significantly by >30% after infusion of L-nitro-arginine-methylester. During iNO only PAP was reduced significantly. Respiratory system compliance decreased significantly after lung lavage, and increased significantly after pulmonary surfactant replacement with concomitant increase of PaO2. In contrast, significant reduction of PAP with iNO before and after pulmonary surfactant replacement were also observed. The reduction ratios of PAP under each condition were 75.2 +/- 7.4%, 81.3 +/- 3.1%, and 79.1 +/- 5.3%, respectively (not significant among conditions). CONCLUSION: These results suggest that iNO is still a potent pulmonary arterial vasodilator even under pulmonary surfactant deficiency in an animal model of pulmonary hypertension.     

Secondary pulmonary hypertension

Recent research has greatly improved our understanding of the pathophysiology of pulmonary hypertension. There is increasing recognition that pulmonary hypertension is an important complication of many childhood respiratory diseases including cystic fibrosis, interstitial lung diseases, upper airways obstruction and disorders of the respiratory muscles and chest wall. Chronic hypoxaemia and, in some cases, destruction of the vascular bed are the key factors. The clinical features of pulmonary hypertension are often overshadowed by those of the primary respiratory disease but newer imaging techniques allow earlier detection of this complication. This may be important in the future if new specific therapies for primary pulmonary hypertension are shown to be beneficial in secondary pulmonary hypertension. With some conditions, such as airways obstruction due to adenotonsillar hypertrophy, treating the underlying cause leads to rapid resolution of the hypertension. However, with most disorders, such as cystic fibrosis, management is focused on treating the lung disease intensively and correcting the chronic hypoxaemia with oxygen therapy, sometimes augmented by nasal mask ventilation. However, although several new selective therapies are effective in idiopathic pulmonary arterial hypertension, their role in secondary pulmonary hypertension remains unclear.     

Congenital pulmonary vein stenosis as a rare cause of pulmonary hypertension]

We report on the history, the diagnostic, and the operative procedure in an infant with congenital stenosis of all pulmonary veins. First symptoms such as failure to thrive, tachydyspnea, tachycardia and hepatomegaly occurred in the eighth week of life. Electrocardiography, 2-dimensional echocardiography and radiography of the chest were unspecific. After recurrent episodes of pulmonary oedema cardiac catheterization was performed: bilaterally elevated pulmonary artery wedge pressure and a normal left atrial pressure proved pulmonary venous obstruction. Severe stenosis of all pulmonary veins was apparent cineangiographically only by selective injections into the right and left pulmonary artery branches in wedge position. The operation (excision of the stenotic area and reimplantation using autologous pericardium) was unsuccessful as in most cases described in the literature. Congenital stenosis of all pulmonary veins is a rapidly progressive malformation. Death occurs usually in the first year of life with and without operation.     

Congenital pulmonary lymphangiectasis

Two cases of congenital pulmonary lymphangiectasis are described in neonates. One case represents an isolated form of the condition. The second example illustrates an association with complex cardiac disease, including total anomalous pulmonary venous drainage, and the asplenia syndrome. The radiological features of congenital pulmonary lymphangiectasis are discussed.     

Intralobar pulmonary sequestration occurring without alteration of pulmonary parenchyma

Typical changes of lung sequestration, including the scimitar sign, were seen on plain films in the left lower lobe. At aortography vasculature of a pulmonary sequestration was seen located paravertebrally in the left posterobasal segment. The arterial supply arose from a division of the thoracic aorta above the diaphragm; venous drainage was to the pulmonary veins. No pulmonary parenchymal changes were detected in the sequestration after resection, nor was there an extrapleural component of the sequestration.     

Progressive pulmonary venous obstruction and pulmonary interstitial fibrosis associated with tetralogy of Fallot

Summary Stenosis of individual pulmonary veins is a rare condition associated with a very high mortality. The present report is the first known case of progressive pulmonary venous obstruction associated with the tetralogy of Fallot. This clinical and anatomical study suggests that initial dynamic and possibly reversible occlusion occurs at the junction of the pulmonary vein and left atrium. Anatomical lesions in pulmonary veins then develop, possibly secondary to functional stenosis. The usually fatal outcome of these cases is due to the development of fixed pulmonary venous occlusion and possibly pulmonary interstitial fibrosis. The rapid progression of pulmonary venous stenosis strongly suggests that discrete veno-atrial stenosis should be surgically corrected as early as possible to prevent the irreversible diffuse pulmonary venous obstruction associated with an invariably fatal prognosis.     

Large fetal pulmonary arteriovenous fistula: impact on pulmonary development

A case report of a patient with a large pulmonary arteriovenous fistula and valvar pulmonary stenosis is presented. The fistula was diagnosed prenatally and its effect on in utero cardiovascular growth and development documented. Due to concerns about massive intrapulmonary shunting potentially causing profound cyanosis after delivery, an EXIT (EX-utero Intrapartum Treatment) procedure was used to transfer the infant from placental to extracorporeal membrane oxygenation (ECMO) support. Severe pulmonary microvascular disease resulted in prohibitive pulmonary hypertension despite surgical ligation of the fistula. Prenatal and postnatal hemodynamic assessments of the fistula are presented and are compared to the pathologic findings.     

Visualization of pulmonary vein obstruction by pulmonary artery wedge injection

Summary One of the major postoperative complications of total anomalous pulmonary venous connection is obstruction of the pulmonary veins. This event may be apparent immediately after surgery when it is usually due to congenitally obstructed veins or later when it may be the result of failure of commensurate growth of the left atrium-common vein anastomosis or of scarring at the anastomotic site. The exact location of the obstruction becomes, then, of paramount importance in deciding if the patient can be helped by further surgery. At cardiac catheterization, pulmonary artery wedge injection was the only angiographic technique that visualized the site and degree of pulmonary venous obstruction in the case reported here.     

肺动脉去神经治疗肺动脉高压研究进展

肺动脉去神经治疗(pulmonary artery denervation,PADN)可阻断局部肺动脉交感神经,降低肺动脉高压(pulmonary arterial hypertension,PAH)血流动力学参数,改善肺血管重塑及右心室心肌肥厚、纤维化,进而改善心室功能。前期基础实验已确定肺动脉交感神经在肺动脉内膜位置,并证实PADN对PAH动物模型安全有效,可能通过抑制交感神经系统和肾素-血管紧张素-醛固酮系统发挥作用。PADN已开展成人临床应用研究,取得良好临床效果。在此基础上正初步探索PADN在儿童PAH中应用的可能性。     

Ductal shunting, high pulmonary blood flow, and pulmonary hemorrhage

OBJECTIVE: To describe the relationship among ductal shunting, estimated pulmonary blood flow, and pulmonary hemorrhage in very preterm infants. STUDY DESIGN: A total of 126 babies born before 30 weeks' gestation (median gestation 27 weeks, range 23 to 29 weeks) underwent echocardiography at 5, 12, 24, and 48 hours of age; measurements included right and left ventricular output, superior vena cava flow, and color Doppler diameter of any ductal shunt. Pulmonary blood flow was derived from the sum of right ventricular output and estimated ductal shunt flow. RESULTS: Twelve (9.5%) babies had a pulmonary hemorrhage at a mean age of 38 hours. Compared with the rest of the cohort, these 12 babies were less likely to have had antenatal steroids (59% vs 90%) and were less mature (26 weeks vs 27 weeks). At the echocardiogram closest to the pulmonary hemorrhage, 11 (92%) of the 12 babies had a significant patent ductus arteriosus >1.6 mm in diameter (median 2 mm, range 0.7 to 2.4 mm), and the median pulmonary blood flow was 326 mL/kg/min (range 210 to 598 mL/kg/min). These measurements were significantly higher than those found in the rest of the cohort in the same period (median duct diameter 0.5 mm [range 0 to 2.9 mm], median pulmonary blood flow 237 mL/kg/min [range 107 to 569 mL/kg/min]). At 5-hour echocardiography the babies with pulmonary hemorrhage had significantly larger diameter ducts but similar pulmonary blood flow. CONCLUSIONS: Pulmonary hemorrhage in preterm babies is associated with significant ductal shunting and high estimated pulmonary blood flow.     

Sildenafil in neonatal pulmonary hypertension due to impaired alveolarisation and plexiform pulmonary arteriopathy

We report a case of severe pulmonary hypertension in a neonate associated with impaired alveolarisation and plexiform pulmonary arteriopathy. Treatment with oral sildenafil in addition to inhaled nitric oxide (NO) resulted in recovery from the pulmonary hypertensive crisis. Long term sildenafil therapy was associated with complete resolution of the pulmonary hypertension.     

肾上腺髓质素缓解低氧性肺动脉高压大鼠肺动脉中胶原堆积的研究

目的：观察长期应用肾上腺髓质素（adrenomedullin, ADM）对慢性低氧性肺动脉高压大鼠肺血管胶原代谢的影响,以探讨ADM对慢性低氧性肺血管结构重建的作用及其可能机制。方法：19只雄性Wistar大鼠随机分为对照组（n=6）、低氧组（n=7）、低氧+ADM组（n=6）。对于低氧+ADM组大鼠,通过微量渗透泵皮下持续给予ADM（300 ng/h）2周。低氧2周后,以右心导管法测定肺动脉平均压,检测右心室与左心室加室间隔比值,观测肺血管显微变化。用免疫组化法检测肺动脉中胶原I、胶原III和转化生长因子（TGF）-β的表达。结果：低氧2周后,大鼠肺动脉平均压明显升高(P<0.01),右心室与左心室加室间隔的比值明显增加(P<0.01),肺小血管肌化程度和肺动脉相对中膜厚度较对照组均明显增高（P<0.01）,同时肺动脉胶原I、胶原III和TGF-β表达增强。与低氧组大鼠相比,低氧+ADM组大鼠肺动脉平均压明显降低（P<0.01）,右心室与左心室加室间隔的比值明显下降（P<0.01）,肺小血管肌化程度和肺动脉相对中膜厚度较低氧组均明显降低（均P<0.01）,同时肺动脉胶原I、胶原III和TGF-β表达减弱。结论：外源性补充ADM可能通过抑制肺动脉TGF-β表达,减少肺动脉壁胶原异常堆积,对低氧性肺动脉高压和肺血管结构重建发挥调节作用。