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We explored whether subnormal forced expiratory volume within 1 s (FEVThe multi-centre, randomised Nonintubated Surfactant Application trial enrolled 211 preterm infants born at 23-26 weeks of gestation from 13 level III neonatal intensive care units from April 2009 to March 2012. They received surfactant via LISA (n = 107) or after conventional endotracheal intubation (n = 104). The follow-up assessments were carried out by a single team blinded to the group assignments. The main outcome was FEVSpirometry was successful in 102/121 children. The other children died or were lost to follow-up. Median FEVThe proportion of children aged 5-9 years with subnormal FEV

Introduction. Transmission of Enterobacterales in neonatal intensive care units (NICU) can cause outbreaks of colonization and invasive infections among neonates. Two clusters of nosocomial transmission of Klebsiella pneumoniae identified by MALDI-ToF mass-spectrometry were suspected at two NICUs in July and August 2016. Aim. To assess the potential transmission of K. pneumoniae among neonates. Methodology. Whole-genome sequencing (WGS) was performed of K. pneumoniae isolates obtained through targeted surveillance of patients and environmental sampling. Results. WGS data revealed that patient and environmental isolates represented two species, K. pneumoniae and K. variicola . Core-genome multi-locus sequence typing (cgMLST) of the isolates identified three separate transmission clusters, in Hospital A a cluster of K. pneumoniae isolates in 12 children and two environmental samples and a second cluster of K. variicola isolates in five children. In Hospital B a cluster of K. pneumoniae isolates from three children and five unrelated isolates of K. pneumoniae and two unrelated isolates of K. variicola were found. Conclusion. K. variicola can cause hospital outbreaks of colonization and infection similar to other Klebsiella spp. Preliminary results from this study were presented at the 27th European Congress of Clinical Microbiology and Infectious Diseases, April 22-25, 2018, Vienna, Austria.

Banner clouds are clouds that appear to be attached to the leeward face of a steep mountain. This paper investigates the role of wind speed and wind shear for the formation of banner clouds. Large-eddy simulations are performed to simulate the flow of dry air past an idealized pyramid-shaped mountain. The potential for cloud formation is diagnosed through the Lagrangian vertical parcel displacement, which in the case of a banner cloud shows a plume of large values in the lee of the mountain. In addition, vortical structures are visualized through streamlines and their curvature. A series of sensitivity experiments indicates that both the flow and the banner cloud occurrence are largely independent of the ambient wind speed U. On the other hand, the shear of the ambient wind has a profound impact on the location of the stagnation point on the windward face as well as on the flow geometry in the lee of the mountain. The relevant measure for shear is H/Hs, where H denotes the height of the mountain and Hs = U/Uz is the scale height of the shear (with Uz denoting the scale of the shear). The simulations are also used to compute the line-of-sight velocity component seen by a hypothetical Doppler wind lidar positioned in the lee of the mountain; the analysis suggests that such sensitivities can potentially be detected using modern wind lidar technology.

Background: Congenital cardiovascular malformations (CCVM) may cause infrequently airway pathologies (AP) in children and are of prognostic and therapeutic relevance. While computed tomography (CT) is considered first-line imaging modality in many centres, we started using magnetic resonance imaging (MRI) more and more in the last years to detect CCVM and AP to avoid radiation in this patient group. Objective: The aim of this retrospective study was to determine and to compare the diagnostic accuracy of CT and MRI when used to detect CCVM and/or AP. Methods: All patients suspected to have CCVM and/or AP and examined either by CT or MRI between 2000 and 2013 in our hospital were included. Extension and type of CCVM, as well as their relationship to esophagus, trachea or bronchi were assessed and related to findings of tracheobronchoscopy, cardiac catheterization or surgery if available. Results: One hundred six patients (median [range] 4 years [2 days to 66 years]) were examined by CT (n = 27) or MRI (n = 79). In 78 patients (74%), CCVM and/or AP were found with either of the imaging methods. CCVM were found in 63 subjects. Forty-six of 63 subjects had both, CCVM and AP. The presence of CCVM was always detected correctly by CT or MRI, although both techniques had a weakness detecting atretic segments directly. AP (n = 61) were correctly diagnosed in all patients not intubated for artificial ventilation by CT (n = 17) and in all but 2 patients by MRI (39 out of 41). Conclusions: MRI is sensitive to detect CCVM associated with AP equally to CT without any radiation exposure.

Background Vancomycin is an extensively used anti-infective drug in neonatal ICUs. However, exposure–toxicity relationships have not been clearly defined. Objectives To evaluate the risk profile for hearing deficits in vancomycin-exposed very-low-birthweight infants (VLBWI). Methods In a large cohort study of the German Neonatal Network (GNN; n = 16 967 VLBWI) we assessed the association of vancomycin treatment and pathological hearing tests at discharge and at 5 year follow-up. We performed audits on vancomycin exposure, drug levels, dose adjustments and exposure to other ototoxic drugs in a subgroup of 1042 vancomycin-treated VLBWI. Results In the GNN cohort, 28% (n = 4739) were exposed to IV vancomycin therapy. In multivariable logistic regression analysis, vancomycin exposure proved to be independently associated with pathological hearing test at discharge (OR 1.18, 95% CI 1.03–1.34, P = 0.016). Among vancomycin-treated infants, a cumulative vancomycin dose above the upper quartile (>314 mg/kg bodyweight) was associated with pathological hearing test at discharge (OR 2.1, 95% CI 1.21–3.64, P = 0.009), whereas a vancomycin cumulative dose below the upper quartile was associated with a reduced risk of pathological tone audiometry results at 5 years of age (OR 0.29, 95% CI 0.1–0.8, P = 0.02, n = 147). Conclusions Vancomycin exposure in VLBWI is associated with an increased, dose-dependent risk of pathological hearing test results at discharge and at 5 years of age. Prospective studies on long-term hearing impairment are needed.

Background Even after successful aortic coarctation (CoA) repair, hypertension causes premature morbidity and mortality. The mechanisms are not clear. The aim was to evaluate elastic wall properties and aortic morphology and to correlate these results with severity of restenosis, hypertension, aortic arch geometry, noninvasive pressure gradients, and time and kind of surgical procedure. Methods Eighty-nine patients (17 ± 6.3 years) and 20 controls (18 ± 4.9 years) were examined using magnetic resonance imaging (MRI). In addition to contrast-enhanced MR angiography and flow measurements, CINE MRI was performed to assess the relative change of aortic cross-sectional areas at diaphragm level to calculate aortic compliance (C). Results Fifty-four percent of all patients showed hypertension (> 95th percentile), but more than half of them had no significant stenosis (defined as ≥30%). C was lower in CoA than in controls (3.30 ± 2.43 vs. 4.67 ± 2.21 [10–5 Pa–1 m–2]; p = 0.024). Significant differences in compliance were found between hyper- and normotensive patients (2.61 ± 1.60 vs. 4.11 ± 2.95; p = 0.01), and gothic and Romanesque arch geometry (2.64 ± 1.58 vs. 3.78 ± 2.81; p = 0.027). There was a good correlation between C and hypertension (r = 0.671; p Conclusion The decreased compliance, a high rate of hypertension without restenosis, and independency of time and kind of repair confirm the hypothesis that CoA may not be limited to isthmus region but rather be a widespread (systemic) vascular anomaly at least in some of the CoA patients. Therefore, aortic compliance should be assessed in these patients to individually tailor treatment of CoA patients with restenosis and/or hypertension.

ObjectiveTo determine if survival rates of preterm infants receiving active perinatal care improve over time.DesignThe German Neonatal Network is a cohort study of preterm infants with birth weight Setting43 German level III neonatal intensive care units (NICUs).Patients8222 preterm infants with a gestational age between 22/0 and 28/6 weeks who received active perinatal care.InterventionsParticipating NICUs were grouped according to their specific survival rate from 2011 to 2013 to high (percentile >P75), intermediate (P25–P75) and low (Main outcome measuresDeath by any cause before discharge.ResultsTotal survival increased from 85.8% in 2011–2013 to 87.4% in 2014–2016. This increase was due to reduced mortality of NICUs with low survival rates in 2011–2013. Survival increased in these centres from 53% to 64% in the 22–24 weeks strata and from 73% to 84% in the 25–26 weeks strata.ConclusionsOur data support previous reports that active perinatal care of very immature infants improves outcomes at the border of viability and survival rates at higher gestational ages. The high total number of surviving infants below 24 weeks of gestation challenges national recommendations exclusively referring to gestational age as the single criterion for providing active care. However, more data are needed before recommendations for parental counselling should be reconsidered.Trial registrationApproval by the local institutional review board for research in human subjects of the University of Lübeck (file number 08–022) and by the local ethic committees of all participating centres has been given.

Despite enormous enhancements in air quality, many cities still have serious problems to comply with the legal limits of air pollution. Concentrations of nitrogen oxides and fine particulate matter remain high, originating in relevant proportions from urban traffic. The impact of traffic-induced immissions on our built heritage is the focus of this study. The proportion of historic buildings exposed to elevated traffic emissions was estimated in five German cities of different sizes and different traffic loads. Less than 100 up to more than 1000 historic buildings per city are exposed to increased traffic emissions. For five buildings at heavy-trafficked roads, the near-field air flow and the deposition rate of air pollutants were modelled. Passive samplers were exposed at these buildings to determine the composition and amount of particulate matter, the concentrations of NO2 and HNO3 in the air, as well as the soiling and the recession rate of stone samples. The results clearly demonstrate the deposition of large amounts of particulate matter and the corresponding soiling of stone samples as consequences of road traffic. Despite high concentrations of NO2, the deposition of nitrates on stone surfaces seems to play a limited role. In addition, the deposition of sulphate and at some exposure sites chloride deposition was observed.

The statistical connection between strong surface cyclones over Europe and long-lived upper-tropospheric Rossby wave trains is examined for the Northern Hemisphere winter season using 45 years of reanalysis data. Dates are selected for which the surface pressure anomaly over Central Europe is below a threshold yielding the 5% of lowest values. Composites of upper tropospheric meridional wind for these dates (including a lead or lag in time) display clear signs of a wave train. The composite wave train lives for over two weeks and propagates eastward over more than 360° longitude. The phase speed of individual lows and highs, by contrast, is close to zero and the same is true for the composite surface low. There is a pronounced northward shift of the wave train as it propagates over the North American East coast. Although this composite wave train is statistically highly significant, there is large scatter about the mean. An index is defined that quantifies the similarity of the upper-tropospheric meridional wind pattern for an arbitrary date with the composite wave train for a certain lead or lag. Given large positive values of the index, there is an enhanced probability of a strong surface cyclone over Central Europe a few days later. Comparison with a previous study focusing on Pacific cyclones shows noteworthy differences.

Besides the enormous improvement of air quality in Germany due to the reduction of sulphur dioxide emissions in the last decades, high immissions of nitrogen oxides and fine particulate matter are frequently observed at traffic-rich urban sites. The changed chemical composition of air pollution requires a new investigation of its impact on historic buildings constructed of natural stone. In a pilot study a multi-disciplinary approach was chosen to obtain information on the actual pollution situation of historic buildings and monuments at traffic hotspots in Germany. The study concentrated on the two German cities of Munich and Mainz of different size, traffic volume and stone inventory. Dose–response functions were calculated to demonstrate the change of impact of different pollutants over the last three decades, and for comparison of traffic hotspots and housing areas of both cities. Numeric modelling on a city-scale was used to identify the historic buildings and monuments affected by elevated traffic immissions. Because a relevant part of these pollutants is dominated by short-range transport, the differences of wind speed and deposition rates were calculated using a street-scale 3D flow and dispersion model regarding traffic volume, wind regime and adjacent buildings. Finally, particulate matter was sampled at different positions of two buildings heavily exposed to traffic emissions. Individual particles were investigated by environmental scanning electron microscopy. After classification of the particles into different chemical groups, the fraction of traffic-induced particulate matter was quantified. Summarizing the results, it must be stated that soiling by traffic-related particulate matter, deposition of nitrates deriving from exhaust emission and other diffusely emitted components bear a severe damage potential for natural building stone at least locally at traffic-rich urban sites.

Cardiac magnetic resonance imaging (MRI) and computed tomography (CT) have been developed rapidly in the last decade. Technical improvements and broad availability of modern CT and MRI scanners have led to an increasing and regular use of both diagnostic methods in clinical routine. Therefore, this German consensus document has been developed in collaboration by the German Cardiac Society, German Radiology Society, and the German Society for Pediatric Cardiology. It is not oriented on modalities and methods, but rather on disease entities. This consensus document deals with coronary artery disease, cardiomyopathies, arrhythmias, valvular diseases, pericardial diseases and structural changes, as well as with congenital heart defects. For different clinical scenarios both imaging modalities CT and MRI are compared and evaluated in the specific context.

The numerical flow and pollutant dispersal model MISKAM has gained a high level of acceptance by meteorological consultants, environmental agencies and other users. This article intends to serve as a reference of the actual state of development of the flow model as well as a comprehensive documentation of its evaluation. It summarises validation experiments for neutrally stratified flow around different obstacle configurations carried out in accordance with the guideline 'Prognostic microscale wind field models - Evaluation for flow around buildings and obstacles' (VDI, 2005). The evaluation procedure includes internal consistency checks as well as comparisons with wind tunnel data. In most of the test cases the performance of MISKAM clearly exceeds the requirements of the guideline. In particular, the model passes the consistency checks perfectly while some deviations occur between model results and measurements. These deviations result either from well-known problems of the turbulence closure adopted by MISKAM or from inconsistencies of the wind tunnel based reference data supplied with the guideline. As a whole, the guideline emerges as a useful tool for model developers as well as users, even though the inclusion of more complex test cases would be worthwhile. (orig.)

BACKGROUND Ventricular dysfunction represents one of the major problems in the long-term follow-up of patients after atrial repair for dextrotransposition of the great arteries. We aimed to study the role of tissue Doppler derived isovolumic acceleration (IVA) to detect early myocardial dysfunction in these patients. METHODS Twenty-four patients with dextrotransposition of the great arteries (D-TGA) that underwent atrial repair (Senning procedure: n = 12; Mustard procedure: n = 12) in infancy were examined at the age of 21 [12-33] years (median [range]) using tissue Doppler analysis of IVA and peak systolic myocardial velocity at rest and during exercise. 12 age-matched healthy subjects served as controls. RESULTS At rest, IVA and peak systolic myocardial velocity were reduced in the systemic ventricle (SV) of patients. IVA correlated with peak systolic myocardial velocity (r = 0.76, P < 0.001). During exercise, IVA, but not peak systolic myocardial velocity, increased significantly in the SV of patients (rest: 1.03 +/- 0.44 cm/sec(2); 1 W/kg: 1.80 +/- 1.22 cm/sec(2); 2 W/kg: 2.85 +/- 1.26 cm/sec(2)). In the subpulmonary ventricle, IVA was significantly lower in patients compared to the controls (patients: 1.45 +/- 0.49 cm/sec(2) vs. controls: 2.31 +/- 0.43 cm/sec(2), P < 0.05). IVA but not peak systolic myocardial velocity was able to discriminate between patients and healthy subjects. CONCLUSIONS IVA is superior to peak systolic myocardial velocity to assess a reduction in functional reserve of both ventricles in patients after atrial repair for D-TGA.

After childhood Kawasaki syndrome (KS) the coronary arteries undergo a lifelong dynamic pathological change, and follow-up coronary artery imaging is essential. At present, conventional coronary catheterization (CCC) and angiography is still regarded as the gold standard. Less-invasive methods such as multidetector CT angiography (MDCT-A) and MRI have been used sporadically. To compare the diagnostic quality of MDCT-A and MRI with that of CCC for coronary imaging in a group of patients with coronary artery pathology after childhood KS. A total of 16 patients (aged 5–27 years) underwent CCC and 16-row MDCT-A and 14 patients MRI (1.5 T). There was 100% agreement between MDCT-A and CCC in the detection of coronary aneurysms and stenoses. MDCT-A was superior for the visualization of calcified lesions. MRI and CCC showed 93% agreement for the detection of aneurysms. Visualization of coronary artery stenoses was difficult using MRI—one stenosis was missed. MDCT-A has excellent correlation with CCC regarding all changes affecting the coronary arteries in the follow-up of childhood KS. In comparison to MDCT-A and CCC, MRI is less precise in the detection of stenotic lesions. Due to its high image quality and ease of performance MDCT-A should be the primary diagnostic modality in patients following childhood KS.

BACKGROUND: Tracheal stenosis in combination with vascular and/or cardiac anomalies is a life-threatening condition in infants and children presenting with severe symptoms of airway obstruction. The optimal surgical treatment of these cases remains controversial. OBJECTIVES: We present here a group of infants and children with combined tracheal malformations and vascular and/or cardiac anomalies. More than 30 % of the stenotic trachea was resected in a subgroup of the patients. A reconstruction with end-to-end anastomosis was achieved on the basis of extensive mobilization of the whole tracheobronchial tree and use of CPB. METHODS: The clinical outcome in 37 children with a median age of 8 (1 - 72) months was analyzed retrospectively. The patients presented with severe airway obstruction in combination with congenital heart defects and/or vascular anomalies. Cardiac catheterization, bronchoscopy and thoracic computer tomography were performed prior to operation. The operations were performed under CPB and consisted of tracheal resection with end-to-end anastomosis or external stabilization. Associated intracardiac and vascular anomalies were repaired simultaneously. RESULTS: All but 1 patient survived and had a straightforward recovery. The patients were extubated under bronchoscopic control with a median intubation time after airway repair of 12.2 days. The average follow-up was 8.4 years (1 - 14 years) and the surviving patients did not show signs of restenosis clinically. A segment longer than 30 % of the tracheal length was resected and reconstructed with end-to-end anastomosis in 57 % of the patients (12 of 21 patients). CONCLUSIONS: Our experience demonstrates that resection of tracheal stenosis and end-to-end anastomosis can be achieved successfully even in cases with stenosis of more than 30 % of the total tracheal length. The use of CBP allowed extensive mobilization of the tracheobronchial tree and resection with end-to-end tension-free anastomotic reconstruction.

PURPOSE To compare the aortic compliance of the normal-sized aorta of adolescents with Marfan syndrome and healthy controls using MR measurements of the aortic distensibility and pulse wave velocity. MATERIALS AND METHODS Fourteen patients (median age: 15 years) and 11 healthy subjects (23 [12 - 32] years) were examined at 1.5 T. The MR protocol included 2D steady-state free precession (SSFP)-CINE MRI of the aortic distensibility and PC-MRI of the pulse wave velocity. All measurements were positioned perpendicular to the descending aorta at the level of the diaphragm for assessing the changes in the aortic cross-sectional areas and additionally above and below this plane for assessing the pulse wave velocity. In addition contrast-enhanced 3D-MR angiography was performed in adolescents with Marfan syndrome to exclude morphologic changes and to prove normal-sized aorta. RESULTS Compared with control subjects, adolescents with Marfan syndrome had significantly decreased distensibility and significantly increased pulse wave velocity (chi (2)-test, p = 0.0002) using an age-related non-linear regression analysis. The related aortic compliance was significantly decreased (chi (2)-test, p = 0.0002). There was a good correlation between the two methods (r = 0.86). A low intraobserver variability was found for both methods (< or = 2 %). CONCLUSIONS MRI allows detecting abnormal elastic aortic wall properties already in the normal-sized aorta of adolescents with Marfan syndrome. Monitoring of these properties could be relevant for evaluating disease onset and progression. MRI has the potential value of compliance measurements for the follow-up and to guide therapy indications.

This paper presents the dry version of a new large-eddy simulation (LES) model, which is designed to simulate air flow and clouds above highly complex terrain. The model is three-dimensional and nonhydrostatic, and the governing equations are sound filtered by use of the anelastic approximation. A fractional step method is applied to solve the equations on a staggered Cartesian grid. Arbitrarily steep and complex orography can be accounted for through the method of viscous topography. The dynamical model core is validated by comparing the results for a spreading density current against a benchmark solution. The model accuracy is further assessed through the simulation of turbulent flow across a quasi two-dimensional ridge. The results are compared with wind-tunnel data. The method of viscous topography is not restricted to moderately sloped terrain. Compared to models using curvilinear grids, it allows this model to be applied to a much wider range of flows. This is illustrated through the simulation of an atmospheric boundary-layer flow over a surface mounted cube. The results show that the dry model version is able to accurately represent the complex flow in the vicinity of three-dimensional obstacles. It is concluded that the method of viscous topography was successfully implemented into a micrometeorological LES model. As will be shown in Part II, this allows the detailed study of clouds in highly complex terrain.

The study was done to determine the clinical feasibility and reproducibility of tissue Doppler echocardiography (TDE) with strain rate imaging (SRI) at rest and under physical exercise in healthy young individuals and to report normal values for parameters of regional myocardial function under exercise. Forty-five young volunteers (age 9–29 years) underwent echocardiography with TDE/SRI at rest and during a bicycle exercise test (2 W/kg body weight). Velocities could be obtained in 93% of segments, whereas strain rate was measurable at least in 80% of segments. Inter- and intraobserver variability for measurement of velocities under exercise was 14% and 9%, respectively for strain rate 28% and 20%. Except for peak strain, values for all other parameters were higher during exercise with the clearest response in the left lateral and the right ventricular wall. (1) Tissue Doppler with strain rate imaging is a practical and robust method for assessment of regional function of both ventricles under exercise. (2) Systolic motion, local myocardial relaxation and contractility increased significantly under physical exercise. These normal values obtained from healthy young subjects can serve as a reference database for further clinical studies.

Purpose To assess the value of multidetector CT (MDCT) for evaluation of vascular anomalies (VA) and associated complications in newborns and infants. Materials and methods Seventy-five children (mean age: 9 +/- 6 months, range: 2 weeks to 24 months) with VA were examined using MDCT (4-, 8- or 16-row; collimation 0.5-1.25 mm; scan time 7-30 s), which was performed under controlled ventilation or free breathing. Image quality was rated using a 5-point scale. Image findings were correlated to echocardiography, conventional catheter angiography (CCA), bronchoscopy, and intraoperative findings. Results High quality MDCT data were almost free of cardiac and respiratory motion. In all cases, VA morphology and topography in relation to adjacent structures, e. g. tracheal and esophageal compression caused by an aortic ring, could be assessed exactly and allowed the final diagnosis. Even aberrant vessels, such as aorto-pulmonary collaterals (MAPCA) with a diameter of less than 1 mm, could be identified and excellently visualized. Eighty percent (60/75) of all patients had benefited from the MDCT: in 31 patients CCA was neither necessary to perform surgical planning nor to exclude a VA; in an additional 29 patients radiation doses and sedation time due to interventional procedures could be reduced markedly. Conclusions MDCT can now be regarded as the modality of choice as a minimally invasive, robust, and accurate technique for the diagnosis of complex VA, their potentially life-threatening complications and preoperative planning even in newborns and infants. Its accuracy for detecting VA appears equivalent to CCA while it is more accurate in delineating potential life-threatening complications.

Background— Operator-independent isotropic 3D MRI may greatly simplify the assessment of complex morphology in congenital heart disease. We sought to evaluate the reliability of this new approach. Methods and Results— In 31 adolescent and adult patients (age, 6 to 42 years; median, 16 years) with congenital heart disease, cardiac morphology was determined with free-breathing (navigator-gated), isotropic, 3D steady-state free-precession (3D SSFP) MRI and independently evaluated by 2 observers. Cardiac diagnoses and multiple distance measurements were compared with conventional MR reference sequences (ie, spin-echo, cine gradient-echo, contrast-enhanced MR angiography) and with echocardiography/cine cardioangiography or surgery. Of the 31 patients, 24 had native congenital heart defects or residual defects after repair that warranted immediate treatment. None of these defects was missed by 3D SSFP. Novel diagnostic issues were discovered in 4 of 31 patients (coronary anomalies, n=3; left juxtaposition of the right atrial appendage in double-outlet right ventricle and transposition of the great arteries, 1). For sizes of valves and vessels, we found minor mean differences of −1.1 to 1.6 mm, with SD ranging from 1.2 to 2.9 mm, demonstrating overall good agreement with standard MRI (Bland-Altman analysis). Interobserver variability of 3D SSFP distance measures was low; mean differences ranged from −1.5 to 1.0 mm, and SD ranged from 0.8 to 2.5 mm. Scatter was lower for extracardiac than intracardiac measures. Conclusions— In adolescents and adults, isotropic 3D SSFP MRI allows reliable assessment of complex cardiac morphology. Distance measurements are accurate and reproducible. Thus, a single operator-independent acquisition may substitute for conventional 2D MRI sequences to accelerate and simplify MR scanning in congenital heart disease.

Purpose: To evaluate time-resolved, multiphasic 3D MR angiography (MRA) for the non-invasive assessment of the pulmonary vascular system in children. Materials and Methods: 10 children aged 6 to 15 years (mean age 10 years) ware examined on a 1.5 T whole body MR system with time-resolved, multiphasic 3D MRA after injection of 0.2 mmol/kg body weight of Gd-DTPA. With the use of an ultrafast gradient echo pulse sequence with asymmetric k-space filling and very short echo and repetition times, a nominal spatial resolution of 1.4 × 1.4 × 2.0 mm 3 could be achieved with a scan time of 5.6 and 6.2 seconds for a single 3D data set. Two radiologists, who were blinded to the clinical diagnosis, analyzed the image data in consensus. The image analysis included the assessment of the image contrast and artifacts as well as a quantitative analysis of the signal-to-noise (SNR) and contrast-to-noise ratios (CNR) for central and peripheral lung vessel segments. Results: The children tolerated all examinations without any side effects. The referral diagnosis, which was based on echocardiography, catheter angiography and surgery, was confirmed by MRA in all cases. The image contrast was rated at least satisfactory in all but one case (19 of 20) and no artifacts were observed. The quantitative analysis of the SNR and CNR in the pulmonary arteries and veins confirmed the reader analysis of a high and uniform contrast throughout the entire pulmonary circulation. Conclusion: Time-resolved multiphasic 3D MRA allows a non-invasive diagnostic evaluation of the pulmonary circulation in children. In view of the excellent image quality, MRA may replace conventional diagnostic catheter angiography in the near future.

Die kardiale Schnittbilddiagnostik mit der Magnetresonanztomographie (MRT) und Computertomographie (CT) hat sich in der letzten Dekade technisch rasant weiterentwickelt. Diese Verbesserungen und die breite Verfugbarkeit moderner CT- und MRT-Systeme haben dazu gefuhrt, dass beide Verfahren regelmasig in der klinischen Routine eingesetzt werden. Dieses deutsche Konsensuspapier wurde daher gemeinsam von der Deutschen Gesellschaft fur Kardiologie – Herz- und Kreislaufforschung (DGK), der Deutschen Rontgengesellschaft (DRG) und der Deutschen Gesellschaft fur Padiatrische Kardiologie (DGPK) erarbeitet und orientiert sich nicht an Modalitaten und Methoden, sondern gliedert sich nach grosen Krankheitsgruppen. Behandelt werden die koronare Herzerkrankung, Kardiomyopathien, Herzrhythmusstorungen, Klappenvitien, Perikarderkrankungen, erworbene und strukturellen Veranderungen sowie angeborene Herzfehler. Fur unterschiedliche klinische Szenarien werden die beiden Schnittbildmodalitaten CT und MRT vergleichend gegenubergestellt und in einem kurzen Textfeld bewertet.

Patients with glutaric aciduria type I are at risk for acute striatal injury precipitated by catabolic stress. Here, we report the successful interdisciplinary anesthetic and perioperative management of a child with glutaric aciduria type I undergoing cardiac surgery with extracorporeal circulation. Given the central focus on prevention of acute striatal injury, our anesthetic strategy emphasized avoiding a high protein load, high-dose inotropics, especially epinephrine (associated with impaired glucose utilization), deliberate hyperventilation, and other interventions associated with systemic inflammatory response.

To assess spatial and temporal pressure characteristics in patients with repaired aortic coarctation compared to young healthy volunteers using time-resolved velocity-encoded three-dimensional phase-contrast magnetic resonance imaging (4D flow MRI) and derived 4D pressure difference maps. After in vitro validation against invasive catheterization as gold standard, 4D flow MRI of the thoracic aorta was performed at 1.5T in 13 consecutive patients after aortic coarctation repair without recoarctation and 13 healthy volunteers. Using in-house developed processing software, 4D pressure difference maps were computed based on the Navier-Stokes equation. Pressure difference amplitudes, maximum slope of pressure amplitudes and spatial pressure range at mid systole were retrospectively measured by three readers, and twice by one reader to assess inter- and intraobserver agreement. In vitro, pressure differences derived from 4D flow MRI showed excellent agreement to invasive catheter measurements. In vivo, pressure difference amplitudes, maximum slope of pressure difference amplitudes and spatial pressure range at mid systole were significantly increased in patients compared to volunteers in the aortic arch, the proximal descending and the distal descending thoracic aorta (p < 0.05). Greatest differences occurred in the proximal descending aorta with values of the three parameters for patients versus volunteers being 19.7 ± 7.5 versus 10.0 ± 2.0 (p < 0.001), 10.9 ± 10.4 versus 1.9 ± 0.4 (p = 0.002), and 8.7 ± 6.3 versus 1.6 ± 0.9 (p < 0.001). Inter- and intraobserver agreements were excellent (p < 0.001). Noninvasive 4D pressure difference mapping derived from 4D flow MRI enables detection of altered intraluminal aortic pressures and showed significant spatial and temporal changes in patients with repaired aortic coarctation.

We introduce a new model-based approach for the segmentation of the thoracic aorta and its main branches from follow-up pediatric 3D MRA image data. For robust segmentation of vessels even in difficult cases (e.g., neighboring structures), we propose a new extended parametric cylinder model which requires only relatively few model parameters. The new model is used in conjunction with a two-step fitting scheme for refining the segmentation result yielding an accurate segmentation of the vascular shape. Moreover, we include a novel adaptive background masking scheme and we describe a spatial normalization scheme to align the segmentation results from follow-up examinations. We have evaluated our proposed approach using different 3D synthetic images and we have successfully applied the approach to follow-up pediatric 3D MRA image data.

An extension of the numerical model MISCAM to account for effects of vegetation is presented. Computed wind and turbulence profiles agree reasonably with wind tunn el data. Furthermore, the extended model yields plausible results for flow fields and pollutant distribution s in an idealized street canyon with and without vegetation. While wind speed is reduced within the vegetated street canyon, a slight increase of pollutant concentrations is found. Zusammenfassung

Objective: In this paper we present an attempt at noninvasive imaging of distributed myocardial electrical activity in patients suffering from myocardial infarction and in healthy subjects. Although advances have been made, noninvasive three-dimensional imaging of cardiac electrophysiological activity is still in its infancy and extending our knowledge of cardiac electrophysiological properties may be a valuable guide in the treatment of patients with coronary artery disease. Methods: Magnetic field mapping data formed the input for an inverse solution that is based on a multiple dipole model. The lead field normalized minimum norm least square criterion was applied to predefined myocardial source geometry. Current density distributions were calculated for the left ventricle during ventricular depolarization. Images from two patients with previous myocardial infarction were compared to images from two healthy subjects. Results: Low regional and global current density was found in the infarction patients. Regions of low current density corresponded to infarcted segments. The images of the healthy subjects displayed less marked areas of low current density. Conclusion: The proposed multiple dipole model may be able to distinguish viable from scarred myocardium. A prospective clinical study should be undertaken to investigate the spatial resolution and the diagnostic performance of this method.

The segmentation of the thoracic aorta and its main branches from medical image data is an important task in vascular image anal- ysis. We introduce a new model-based approach for the segmentation of these vessels from follow-up 3D MRA images of children. For ro- bust segmentation we propose an extended parametric cylinder model which requires only relatively few parameters. The new model is used in conjunction with a two-step fitting scheme for refining the segmen- tation result yielding an accurate segmentation of the vascular shape. Moreover, we include a novel adaptive background masking scheme and we use a spatial normalization scheme to align the segmentation results from follow-up examinations. We have evaluated our proposed approach using 3D synthetic images and we have successfully applied the approach to follow-up 3D MRA images of children.

The stereoselective syntheses of thienyl and furyl analogues of ephedrine starting from ( R )- and ( S )-cyanohydrins, respectively, are described. Addition of methyl Grignard to the O-trimethylsilyl protected optically active cyanohydrins ( R )- and (S)- 3 and hydrogenation of the resulting imino intermediates gives the erythro -2-amino alcohols 4 with high diastereoselectivity. Their reductive methylation leads to the enantiomerically pure thiophene analogues (1 S ,2 S )- and (1R,2R)- 6a , (1 R ,2 S )- and (1S,2R)- 6b as well as to the furan analogues (1S,2S)- 6c and (1R,2S)- 6d of ephedrine. The biological activity of the new compounds is under investigation.

Purpose: To assess spatial and temporal pressure changes in patients with repaired aortic coarctation compared with young healthy volunteers using 4D flow MRI and derived 4D pressure difference maps. Methods: 4D flow MRI of the thoracic aorta was performed at 1.5 T in 13 patients after aortic coarctation repair without recoarctation (mean age: 18.8 years, 5 female, 8 male) and 13 healthy volunteers (mean age: 22.9 years, 4 female, 9 male). 4D pressure difference maps were computed based on the Navier-Stokes equation. The thoracic aorta was divided into four segments: ascending aorta, aortic arch, proximal descending aorta, and distal descending aorta. Results: Mean spatial pressure range at mid systole for patients/volunteers was (in mm Hg): ascending aorta 1.8/1.6 (p= ns), arch 4.8/1.7 (p= 0.02), proximal descending 8.9/1.6 (p < 0.001), and distal descending 2.8/1.6 (p= 0.002). Spatial pressure profiles along the aortic centerline demonstrated pressure gradients in patients affecting both aortic arch and proximal descending aorta. Mean maximum slope of local pressure amplitudes for patients/volunteers was (in mm Hg/cm): ascending aorta 7.4/2.5 (p= ns), arch 6.6/2.1 (p < 0.001), proximal descending 12.1/1.9 (p= 0.002), and distal descending 3.9/2.1 (p= 0.002). Conclusion: Noninvasive 4D pressure difference mapping derived from 4D flow MRI showed significant spatial and temporal changes in patients with repaired aortic coarctation compared with young healthy volunteers, particularly affecting aortic arch and proximal descending aorta, but also distal descending aorta. The technique can characterize such changes not only noninvasively but also in great detail.

AIM The aim of this study was to evaluate the morphology and elastic properties of the aorta in children and adolescents with Ullrich-Turner syndrome (UTS) treated with growth hormone, by using magnetic resonance imaging (MRI). METHODS Thirty-seven conscious UTS patients were examined using a 1.5-T whole-body MRI. Contrast-free three-dimensional (3D)-MR angiographies were performed, including 2D cine MRI, to calculate the aortic compliance (C) and cine of the aortic valve. RESULTS Changes of aortic morphology were evident in 40% of the patients, whereas six had more than one alteration. A bicuspid aortic valve was identified in three patients that were missed by previous echocardiography. The aortic compliances in UTS patients were similar to those in healthy persons. CONCLUSION This study shows that aortic morphology and compliance can be assessed by MRI without using contrast agents and without sedation in children and adolescents with UTS.

(R)-Cyanohydrins (R)- 2b-h are obtained in good optical yields by (R)-oxynitrilase catalyzed enantioselective addition of HCN to β-substituted pivalaldehydes 1b-h. Under optimized reaction conditions with highly purified (R)-oxynitrilase, hydroxypivalaldehyde (1a) is converted to (R)- 2a in satisfactory chemical and optical yields. By acid-catalyzed hydrolysis the cyanohydrins (R)- 2a-h cyclize directly to give crude (R)-pantolactone (R)- 3 with ee-values of 56–95% which, after recrystallization, go up to ≥98 %ee in all cases.

Recent advances in flow-sensitive magnetic resonance imaging (MRI) and data analysis allow for comprehensive noninvasive three-dimensional (3D) visualization of complex blood flow. Electrocardiogram (ECG)-gated three-directional (3dir) flow measurements were employed to assess and visualize time-resolved 3D blood flow in the pulmonary arteries (PA) and thoracic aorta. We present findings in a juvenile patient with surgically corrected transposition of the great arteries (d-TGA) and aortic coarctation. For the first time, the complex flow patterns in the PA following d-TGA were visualized. Morphologically, a slight asymmetry of the PA was found, with considerable impact on vascular hemodynamics, resulting in diastolic retrograde flow in the larger vessel and diastolic filling of the smaller PA. Additionally, increased flow to the supraaortic vessels was found due to aortic coarctation.

Endothelin-1 (ET-1) is an endogenous vasoconstrictive peptide hormone and asymmetric dimethylarginine (ADMA) acts as an endogenous inhibitor of nitric oxide synthase. We hypothesized that both could contribute to pulmonary hypertension in patients with left-to-right shunt after intracardiac repair.We prospectively analyzed ET-1 and ADMA plasma levels in 31 patients (m = 16; f = 15) at an age of 0.6 [0.2-27] years (median [range]) with left-to-right shunt (ASD II: n = 12; VSD: n = 11; AVSD: n = 8) presenting with a Qp/Qs of 2.7 [1.4-6.3] and a pulmonary arterial mean pressure (PAP) of 23 [13-57] mmHg. Blood specimens were taken prior to cardiopulmonary bypass (CPB), after weaning from CPB and at 3, 6, 12 and 24 h after CPB.12/31 patients were found to have pulmonary hypertension prior to intracardiac repair and 11/12 patients showed persistent pulmonary hypertension during the first 24 h after CPB. Patients with pulmonary hypertension at 12 h after CPB showed significant higher plasma ET-1 compared with patients with normal PAP (1.4 [0-7.9] versus 0.5 [0-2.5] pg/ml; P = 0.048 (Mann-Whitney)). Plasma ADMA decreased from 1.3 [0.75-2.3] micromol/l before CPB to 0.7 [0.4-2.1] micromol/l at 12 h (P0.05). However patients with pulmonary hypertension did not show different ADMA plasma levels.Increased plasma ET-1 but not inhibition of nitric oxide synthase by ADMA is associated with pulmonary hypertension after intracardiac repair.

Evaluation of the severity and the follow-up of aortic insufficiency (AI) are important tasks in paediatric cardiology. Assessment is based on clinical and echocardiographic (ECHO) findings such as the configuration of the valve and the regurgitation fraction (RF). The goal of this study was to evaluate MRI compared to ECHO for determination of clinical severity, valve morphology and RF. Thirty patients (age 3–27 years) with mild-to-severe AI were evaluated by clinical examination, ECHO (2-D and Doppler), and MRI at 1.5 T (2-D true-FISP cine short axis, phase-contrast flow in the ascending aorta). Both methods identified 13 bicuspid and 17 tricuspid valves. Good correlations between ECHO and cine MRI were found for ventricular mass, stroke volume, and ejection fraction. A good linear correlation was found for the RF determined by ECHO and phase-contrast MRI (r = 0.7). The RF was 6% in mild AI, 17% in moderate AI, and 30% in severe AI. The different severity groups showed significantly different RF and it was possible to discriminate between clinical severity grades (P = 0.01). ECHO and MRI showed good agreement in evaluating morphology and function of the left ventricle. The clinical severity of the disease can be evaluated correctly using MRI.

Congenital heart disease (CHD), including complex anomalies of the pulmonary arteries, are now earlier diagnosed and treated. Due to improvements in interventional and surgical therapy, the number of patients with the need for follow-up examinations is increasing. Pre- and postinterventional imaging should be done as gently as possible, avoiding invasive techniques if possible. With the technical improvement of multidetector-row computed tomography (MDCT) and magnetic resonance imaging (MRI), both techniques are increasingly used for noninvasive assessment of the pulmonary vasculature in children with CHD. Knowledge of the most common diseases affecting the pulmonary vasculature and the kind of surgical and interventional procedures is essential for optimal imaging planning. This is especially important because interventions can be positively influenced by high-quality imaging. Therefore, the most common diseases and procedures are described and imaging modality of choice and important image findings are discussed.

Previous studies have suggested the feasibility of a non-invasive quantification of vascular trans-stenotic pressure gradients (DeltaP) by phase-contrast MR imaging (PC-MRI). Our purpose was to assess the value of MRI estimated pressure gradients as a screening tool for assessing hemodynamically significant (re-)coarctation of the aorta (CoA) in pediatric patients.Forty-three patients (median age (range), 16 (5-25) years) with CoA (38 postoperative and 5 native) and clinically suspected hemodynamically significant stenosis underwent quantitative and semi-quantitative PC-MRI blood flow measurements and 3D MR-angiography, Doppler ultrasound (US) and conventional catheter angiography (CCA, n=20). Estimated DeltaP for each modality was correlated with percent stenosis.The percent stenosis correlated only moderately with DeltaP(MRI) (r=0.55, p0.001) and DeltaP(CCA) (r=0.48, p0.001). Only moderate correlations were observed between DeltaP(MRI) vs. DeltaP(CCA) (r=0.54, p=0.02) and vs. DeltaP(US) (r=0.40, p=0.01). In contrast, semi-quantitative analysis of PC-MRI flow profiles predicted with good sensitivity (88%) and specificity (88%) who would be operated on. Thirteen patients met hemodynamic and percent stenosis criteria by CCA for surgical intervention.Measured pressure gradients using PC-MRI should be used cautiously when assessing patients for recoarctation of the aorta. The analysis of blood flow profiles by PC-MRI might be a promising alternative in assessing the hemodynamic significance of CoA.

A 55-year-old woman with congenital heart disease and increasing dyspnea at low levels of exertion was referred to our department for imaging. Clinical findings were cyanosis of the lips and clubbing of the fingers. The past medical history included several hospitalizations for dyspnea, tachycardia, recurrent pulmonary embolism, and suspected cerebral embolism. Despite several conventional angiographic studies, the exact classification of the congenital heart disease and the vascular abnormalities had not been made …