Evaluation of a noninvasive cardiac output monitor in mechanically ventilated children.

OBJECTIVE: To compare measurements of cardiac output (CO) and cardiac index (CI) obtained by a recently developed noninvasive continuous cardiac output system, NICO (CONICO), and transthoracic Doppler echocardiography (COTTE) in mechanically ventilated children. DESIGN AND SETTING: Prospective study in a university-affiliated tertiary pediatric intensive care unit. PATIENTS: A total of 21 mechanically ventilated children, weighing >15 kg, in stable respiratory and hemodynamic condition. MEASUREMENTS: Sets of three successive measurements of CO with the NICO system and transthoracic Doppler echocardiography were obtained. Bland-Altman analysis was used to compare the agreement between the two methods. RESULTS: The mean +/- sd CO values were 4.06 +/- 1.43 L/min for CONICO and 4.67 +/- 1.78 L/min for COTTE. Bias +/- sd between the two methods was -0.61 +/- 0.94 L/min. The variability of the difference between the two methods increased as the magnitude of the CO measurement increased. Similar results were obtained for cardiac index: 4.01 +/- 1.40 L.min.m for CINICO and 4.59 +/- 1.48 L.min.m for CITTE. Bland-Altman analysis revealed a nonuniform relationship between CI difference and the magnitude (y = -0.299 - 0.0655 x mean). The variability of the differences did not increase as the magnitude of the CO measurement increased (sd of estimate was 0.827 L.min.m). With both CONICO and CINICO, each measurement was highly repeatable, with coefficient of variation of only 2.88% +/- 2.31%. Repeatability with Doppler echocardiography was 7.02% +/- 4.33%. CONCLUSIONS: The NICO system is a new device that measures CO easily and automatically in mechanically ventilated children weighing >15 kg. CO values obtained with this technique were in agreement with those obtained with Doppler echocardiography in children in respiratory and hemodynamic stable condition. The NICO system needs further investigation in children in unstable respiratory and hemodynamic condition.     

Ecocardiografía funcional en cuidados intensivos neonatales: experiencia en una unidad española a lo largo de un año

IntroductionSeveral publications highlight the usefulness of functional echocardiography (FnECHO) in neonatal intensive care. Data is lacking on its use in units neonatal in Spain.ObjectivesTo evaluate frequency of use, patient characteristics, indications, measurements, and impact on patient management of FnECHO in a neonatal intensive care unit (NICU) in Spain over a 1 year period.MethodsA retrospective study conducted in NICU patients during 1 year. Variables: gestational age, birthweight, admission criteria, days of life at examination, indication for FnECHO, parameters assessed, and treatment modifications.Results168 echocardiographic studies were performed in 50 patients (mean 3,4. SD 2,83). The most frequent indication was patent ductus (PDA) assessment (58.3%), followed by hemodynamic instability (22.2%). The results of FnECHO modified treatment in 62 cases (36.9%). In 17.4% of them treatment with ibuprofen was initiated, and in 1.2% it was discontinued. In 10.8% of the cases, the results of FnECHO modified hemodynamic support. Echocardiographic evaluation included: assessment of presence/hemodynamic significance of PDA (100%); myocardiac function: ejection fraction/shortening fraction (EF/SF) 23.8%, left ventricular output 24.4%, right ventricular output 21.4%, systemic blood flow 42.3%; and signs of pulmonary hypertension 7.7%.ConclusionsFnECHO is frequently used in the NICU, and in many cases it guides treatment. PDA assessment and hemodynamic instability are the most frequent indications. It still needs to be elucidated if the use of FnECHO modifies patient outcomes.     

Echocardiography and the Neonatologist

Pediatric echocardiography as performed and interpreted by pediatric cardiologists provides details of cardiac structure and function as well as hemodynamic data. Functional echocardiography, in contrast to echocardiography as performed by the cardiologist, is the bedside use of cardiac ultrasound to follow functional and hemodynamic changes longitudinally. Data reflecting cardiac function and systemic and pulmonary blood flow in critically ill preterm and term neonates can be monitored using this method. Functional echocardiography is being developed and driven by neonatologists as an extension of their clinical skills. A wealth of hemodynamic information can be derived from functional echocardiography used for the sick neonate, which provides clinical information different from the assumed underlying physiology. Lack of access to appropriate training programs and interdisciplinary politics is limiting the use of this potentially valuable clinical information. Without the use of functional echocardiography, clinicians are left to speculate as to the underlying pathophysiology of circulatory compromise, and the assumptions they make often are incorrect. For functional echocardiography to fulfill its clinical potential, it needs to be available at any time and at short notice in the neonatal intensive care unit (NICU). Because most NICUs do not have external diagnostic services to provide longitudinal hemodynamic follow-up assessment at the bedside, neonatologists should be able to develop appropriate echocardiographic skills in close collaboration with their cardiologist colleagues.     

重症手足口病循环障碍的识别与救治

儿童手足口病危重症大多由肠道病毒71型感染引起,部分重症患儿出现循环功能障碍,可能与肠道病毒71型感染导致的严重神经系统损伤有关,发生机制为复杂病理生理过程,与中枢神经系统损伤后神经、体液、生物活性因子等多方面改变有关.儿科医生应密切观察重症预兆.密切监测循环状态和血流动力学指标、仔细评估心脏功能并早期干预是救治成功的关键.

Abstract：

Enterovirus 71 infection was the most important agent related to severe and fatal cases of hand,foot and mouth disease in children. Some severe and fatal cases had cardiovascular dysfunction, which extremely possibly caused by central nervous system involvement and lesions with EV71 infection. But the mechanism was complex and unclear. Monitoring circulation condition and hemodynamic parameters, assessing cardiac function carefully were helpful to detect children at risk of cardiovascular involvement and dysfunction. Early recognition and intervention of children at risk of cardiovascular disorder is the key to rescue severe cases and reduce the mortality.     

风湿性心脏炎心脏超声改变的研究

目的　了解风湿性心脏炎患儿心脏受累情况 ,探讨超声心动图对本病的价值。方法　总结分析2 2 8例风湿性心脏炎患儿的心电图及超声心动图特点 ,比较两者诊断房室肥大的敏感性 ,观察治疗前后心脏超声改变。结果　心电图异常者 1 66例 (73 .1 % ) ,以房室传导阻滞最多见 (67例 ,40 .4% ) ;治疗前 1 66例行心脏超声检查 ,1 62例 (97.6 % )显示不同程度的房室扩大 ,其中以左房大最多见 (1 0 4例 ,62 .7% ) ,1 66例患儿心脏瓣膜均有改变 ,主要表现为二尖瓣返流、增厚及狭窄和主动脉瓣返流 ,其中以二尖瓣返流最多见 (1 0 8例 ,65 .1 % ) ;超声诊断左房大、左室大的敏感性明显优于心电图 ;部分患儿左室收缩功能左室射血分数、心脏指数降低 ,舒张功能E/A <1 ;治疗后复查心脏超声二尖瓣返流、增厚可消失。结论　超声心动图对儿童风湿性心脏炎的诊断及治疗随访具有重要价值     

Two-dimensional and Doppler echocardiographic assessment of variably shaped ductus arteriosus by the parasternal approach

Summary Parasternal two-dimensional and Doppler echocardiography were compared with angiographic, surgical, and postmortem data in 213 patients with various forms of congenital heart disease for its accuracy in determining patency and anatomy of the ductus arteriosus (DA). The age range of the examined patients was from 1 day to 4 years (mean, 7.4 months). Echocardiography was always performed before any invasive procedure. An adequate window for imaging the DA was obtained by parasternal, two-dimensional echocardiography in 209 patients (98%). A persistent ductus arteriosus (PDA) was detected by invasive methods in 79 of 209 patients (38%), and by two-dimensional and Doppler echocardiography in 76 (sensitivity, 96%; specificity, 100%). The echocardiographic and angiographic findings agreed closely as to the duct's morphology. Our technique permits an accurate visualization of the duct in neonates, infants, and small children with various forms of congenital heart disease.     

Does echocardiography facilitate determination of hemodynamic significance attributable to the ductus arteriosus?

Introduction  The assignment of hemodynamic significance to a patent ductus remains a challenge for neonatal intensivists. The impact is medical uncertainty and ongoing debate as to when treatment should be provided if ever. Discussion  Patent ductus arteriosus is associated with significant neonatal morbidities including necrotizing enterocolitis and brain injury; causality has not been proven. In addition, there are limited data suggesting a beneficial effect of therapeutic intervention. The inability to accurately differentiate the pathological ductus arteriosus from the innocent ductus arteriosus may contribute, in part, to the lack of scientific evidence of benefit or causality. Our group has previously proposed the need for a staging system to characterize the clinical and echocardiography impact of the ductus arteriosus. This approach requires comprehensive echocardiography evaluation to assess ductal size and the degree of pulmonary overcirculation/systemic hypoperfusion related to the transductal shunt. Conclusion  In this review, we will highlight the evidence for echocardiography markers of hemodynamic significance and speculate as to how they may facilitate improved decision making in the neonatal intensive care unit.     

Coronary Blood Flow in Healthy Neonates: Effects of Left Ventricular Function and Mass

This study used transthoracic echocardiography, including pulsed-wave Doppler, to register coronary flow parameters in 55 healthy neonates. Intraobserver variability was tested in 20 neonates. A Doppler tracing of sufficient quality for analysis was obtained in the left anterior descending coronary artery (LAD) in 53 of 55 studies (96.4% feasibility) and in the right coronary artery (RCA) in 11 of 55 studies (20.0% feasibility). Estimation of intraobserver variability showed coefficients of variation of 7.5–8.0% for diastolic LAD Doppler flow parameters and volume flow but 17.5% for systolic peak flow velocity. Doppler flow parameters were significantly higher in the LAD than in the RCA. Correlation was found between LAD Doppler flow parameters and age, left ventricular (LV) mass, mitral peak early wave velocity as a measure of diastolic LV function, and the aortic velocity time integral/minute as a measure of systolic LV function. This study shows that diastolic LAD Doppler flow parameters and flow volume can be obtained in neonates by transthoracic echocardiography with acceptable reproducibility. In healthy neonates, left coronary flow parameters are linearly related to age, LV mass, and LV systolic and diastolic function. RCA flow parameters in neonates are lower than in the LAD.     

Intraoperative Rhythm Analysis Using Pulmonary Venous Doppler: Importance of Atrioventricular Interval

Inappropriate timing or duration of the atrioventricular (AV) interval with DDD pacing can lead to hemodynamic compromise. Intraoperative pulmonary venous Doppler interrogation by transesophageal echocardiography can be a valuable tool to assess subtle rhythm abnormalities that may go unnoticed by electrocardiogram and hemodynamic monitoring. We describe a dramatic example of hemodynamic improvement following pacemaker adjustment after pulmonary venous Doppler identified an inappropriately short AV interval.     

Changes in plasma concentrations of atrial natriuretic peptide during exchange transfusion in premature infants

Plasma concentrations of atrial natriuretic peptide (ANP) and hemodynamic parameters were investigated in five premature infants undergoing exchange transfusion. Baseline values of ANP were 51.7 +/- 21.2 fmol/ml. Volume depletion by withdrawal of 10 ml blood did not cause changes in systolic blood pressure (79.4 +/- 4.3 vs. 71.4 +/- 5.6 mmHg) and heart rate (115 +/- 5.2 vs. 115 +/- 2.4 b/min). ANP levels in plasma remained unaltered (53.4 +/- 24.9 fmol/ml). Replacement of 10 ml blood increased central venous pressure by 33% and ANP concentration in the plasma by nearly 30%, while heart rate and blood pressure remained unchanged. Our data indicate that the heart of the premature infant responded to acute blood replacement with increased ANP-release, while blood removal appeared not to influence hormone regulation.     

Changes in Plasma Concentrations of Atrial Natriuretic Peptide during Exchange Transfusion in Premature Infants

ABSTRACT. Plasma concentrations of atrial natriuretic peptide (ANP) and hemodynamic parameters were investigated in five premature infants undergoing exchange transfusion. Baseline values of ANP were 51.7 ± 21.2 fmol/ml. Volume depletion by withdrawal of 10 ml blood did not cause changes in systolic blood pressure (79.4 ± 4.3 vs. 71.4 ± 5.6 mmHg) and heart rate (115 ± 5.2 vs. 115 ± 2.4 b/min). ANP levels in plasma remained unaltered (53.4 ± 24.9 fmol/ml). Replacement of 10 ml blood increased central venous pressure by 33% and ANP concentration in the plasma by nearly 30%, while heart rate and blood pressure remained unchanged. Our data indicate that the heart of the premature infant responded to acute blood replacement with increased ANP-release, while blood removal appeared not to influence hormone regulation.     

Value of antenatal echocardiography in high risk patients to diagnose congenital cardiac defects in fetus

Results of fetal echocardiography in 1062 high risk pregnant patients are described. It was performed before 28 weeks of gestation in 770 cases. These were 38 abnormal scans (3.6%). A fetal arrhythmia was diagnosed in 14 cases and structural abnormality of the heart in 24. Complete atrioventricular block was commonest (n=12), structural heart disease associated in two of these cases. Other lesions identified were atrioventricular septal defect (n=5), hypoplastic left heart syndrome (n=4), ventricular septal defect (n=4), Ebstein’s anomaly (n=3), coarctation of aorta (n=2) and others (n=9). Postnatal confirmatory echocardiography is available in a total of 993 babies including 36 of 38 abnormal cases. There were eleven neonatal deaths amongst babies with abnormal scans. Errors in interpretation were observed in six instances. An anomaly was missed in five cases; in two of these, the main cardiac malformation was picked up but secondary lesions were missed. In one case, a false positive diagnosis of atrial septal defect was made. These errors did not influence the management of the pregnancy. Fetal echocardiography is a very sensitive (91.6%) and specific (99.9%) tool for antenatal diagnosis of congenital heart disease in high risk pregnancies. The information so obtained helps in guiding the optimal obstetric and neonatal management of these cases.     

Multidetector CT evaluation of total anomalous pulmonary venous connections: comparison with echocardiography

Background  Although echocardiography is the first-line imaging modality in the diagnosis of total anomalous pulmonary venous connection (TAPVC), multidetector CT (MDCT) could have advantages in the diagnosis of TAPVC in certain cases. Objective  To compare MDCT with echocardiography in the evaluation of TAPVC. Materials and methods  Enrolled in the study were 23 patients with surgically proven TAPVC. The echocardiography and MDCT findings were independently interpreted by a paediatric cardiologist and cardiac radiologist in terms of: (1) the drainage site of the common pulmonary vein, (2) stenosis of the vertical vein, and (3) the course of the atypical vessel into the systemic vein in the case of vertical vein stenosis. The findings from both modalities were correlated with the results obtained at surgery (n=22) or autopsy (n=1). Results  In all patients, MDCT correctly depicted the drainage site of the common pulmonary vein, stenosis of the vertical vein and the course of the atypical vessel into the systemic vein (sensitivity 100%, specificity 100%). The specificity of echocardiography was 100% for the three defined findings. The sensitivity of echocardiography, however, was 87%, 71% and 0%, respectively. Conclusion  MDCT can facilitate the diagnosis of TAPVC in certain cases.     

Estimates of Interventricular Septum Thickness Are Markedly Affected by the Method Used

Modern echocardiographic techniques allow precise measurements of interventricular septum thickness by two-dimensional echocardiography (2DE) and M-mode echocardiography. The advantage of 2DE is the more accurate estimate in cases in which the shape of the septum differs from normal. However, the usefulness of measurements by 2DE is limited due to the lack of reference values. We measured maximal septum thickness by 2DE in 168 healthy subjects aged 2 to 27 years and compared the results to those obtained by M-mode. In agreement analysis the bias ± 2 SD between 2DE and M-mode was 0.8 ± 1.7 mm (p < 0.001). Maximal septum thickness exceeded the upper normal limit (+2 SD) of the largest pediatric reference data in 14 (8%) of the healthy subjects studied. Interventricular septum thickness is greater when measured by 2DE than by M-mode. Previous M-mode reference values should be used with caution; preferably, reference data based on 2DE should be used.     

Safety and Efficacy of Intravenous Contrast Imaging in Pediatric Echocardiography

This study was performed to determine the safety and efficacy of intravenous contrast echocardiography in children attending a tertiary cardiac center. This was a prospective study to evaluate the use of Optison contrast agent in children with severely limited transthoracic echocardiographic windows. Twenty children (median age, 15 years; range, 9–18) underwent fundamental imaging (FI), harmonic imaging (HI), and HI with intravenous contrast (Optison FS-069). Endocardial border delineation was determined based on a visual qualitative scoring system (0, none: 4, excellent). Endocardial border definition was significantly improved in all patients using contrast echocardiography (FI vs Optison, p < 0.001 for each). Improved border definition was most dramatic in the apical and left ventricular (LV) free wall regions. Left ventricular ejection fraction (LVEF) was measurable in 20 patients (100%) using contrast compared to 11 (55%) with FI or HI (p < 0.05). The echocardiographic diagnosis was correctly delineated in 1 patient with a severely dyskinetic LV segment only with use of intravenous contrast and HI. No patients suffered adverse hemodynamic effects, changes in taste, or flushing episodes. Three patients experienced transient headaches. Intravenous contrast echocardiography offers an additional tool in evaluating children with very poor transthoracic echocardiographic windows. Such a strategy increases diagnostic accuracy and allows accurate LVEF determination. Adverse hemodynamic effects related to intravenous contrast are exceedingly rare.     

Tetralogy of Fallot with infective endocarditis: an echocardiographic explanation of misleading clinical signs

Echocardiography has a known key role in the diagnosis of infective endocarditis, the diagnosis of complications, follow-up evaluation after therapy, and prognostic assessment Habib (Eur J Echocardiogr 11:202–219, 3). This report describes a boy with tetralogy of Fallot who presented with infective endocarditis and large vegetation occluding the ventricular septal defect, thus resulting in a hemodynamically restrictive ventriculoseptal defect with misleading clinical signs. This case illustrates the role of echocardiography in both explaining clinical signs and providing hemodynamic data.     

Functional Echocardiography in the Neonatal Intensive Care Unit

The role of functional echocardiography in neonatal intensive care unit is rapidly evolving, and increasingly neonatologists are using it in making clinical decisions in sick infants. Functional echocardiography can provide a direct assessment of hemodynamics on bedside, and may be considered as an extension of the clinical examination to evaluate cardiovascular wellbeing in the critically-ill infant. The physiological information may be used in targeting specific intervention based upon the underlying pathophysiology. Functional echocardiography is being used for diagnosis of pulmonary hypertension, patent ductus arteriosus, hemodynamic evaluation, assessment of cardiac function, and recognition of pericardial effusion and cardiac tamponade in the neonatal intensive care setting. Despite of its increasing popularity, there is a paucity of structured training programs for neonatologists to acquire skills in echocardiography. This review article discusses clinical applications of functional echocardiography in the neonatal intensive care unit.     

超声心动图诊断儿童心脏肿瘤24例病例系列报告

目的：总结超声心动图诊断儿童及青少年心脏肿瘤的特点及临床治疗经验。方法：纳入2013年1月至2020年1月于首都医科大学附属北京安贞医院儿童心血管病中心住院治疗的心脏肿瘤患儿,对其超声心动图表现及临床资料进行回顾性分析。结果：24例患儿进入本文分析,20例行肿瘤完整切除术,4例行肿瘤部分切除术。术后病理显示良性病变19例（79.2%）,恶性病变1例（4.2%）,生物学行为未明性肿瘤4例（16.7%）;黏液瘤7例,横纹肌瘤6例,炎性肌纤维母细胞瘤4例,纤维瘤3例,纤维肉瘤、畸胎瘤、血管瘤和血栓各1例。心脏肿瘤发生部位以右心室、左心房多见。超声诊断与手术后病理诊断符合率29.2%（7/24）。黏液瘤超声表现特异性强,超声与手术后病理诊断符合率85.7%（6/7）,黏液瘤的超声特征性表现包括：低至中等回声,分叶状,形态不规则,结构松散,活动度大,均有蒂附着;形态会随心脏的收缩和舒张改变,舒张期瘤体不同程度嵌入房室瓣口,引起房室瓣继发狭窄。结论：儿童心脏肿瘤以良性肿瘤多见,病理类型以黏液瘤、横纹肌瘤为主。黏液瘤超声诊断符合率高。     

Captopril in children with dilated cardiomyopathy: Acute and long-term effects in a prospective study of hemodynamic and hormonal effects

Summary Hemodynamic and hormonal effects of captopril were prospectively studied in 12 children (median age 5.8 years, range 4 weeks to 15 years) with dilated cardiomyopathy. A mean dose of 1.83 mg captopril/kg body weight was administered in three or four single doses depending on age.Left ventricular volume, ejection fraction (EF), cardiac index (CI), and systemic vascular resistance (SVR) were noninvasively determined by two-dimensional (2D) and Doppler echocardiography before and 2 days and 3 months after the onset of treatment. Blood pressure and heart rate were recorded as well. Additionally, on the day hemodynamic measurements were made, plasma renin activity (PRA), serum aldosterone, and plasma atrial natriuretic peptide (ANP) concentrations were determined. Plasma catecholamines were measured before and 2 days after captopril treatment. Concomitant medication was kept constant during the short-term phase of captopril treatment. During long-term therapy, diuretics were reduced according to the clinical status. Stroke volume (SVI) (–7%), end-systolic (ESVI) (–31%), and enddiastolic (EDVI) (–21%) volume indexes were significantly reduced (p<0.05) during short-and long-term therapy. The remaining hemodynamic parameters showed only minor, statistically not significant, changes. During short-term therapy, median serum aldosterone levels fell from 138–88.5 pg/ml (p<0.05), and plasma ANP decreased from 144–94 pg/ml (p<0.05). After 3 months these effects were less marked and statistically no longer significant. Changes in PRA and plasma catecholamines were not statistically significant at any time.Captopril thus exerted beneficial hemodynamic effects in these children with dilated cardiomyopathy by reducing left ventricular volume load. Acute hormonal drug effects were distinctly weakened during long-term therapy, while hemodynamic improvement was maintained.