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41.

Background

The atrio-pericardial anastomosis (APA) uses a pericardial pouch to create a large communication between the left atrium and the pulmonary venous contributaries in order to avoid direct suturing of the pulmonary veins during the repair of congenital cardiac malformations. Post-operative imaging is routinely performed by echocardiography but Cardiovascular Magnetic Resonance (CMR) offers excellent anatomical imaging and quantitative information about pulmonary blood flow. We sought to compare the diagnostic value of echocardiography and CMR for assessing pulmonary vein anatomy after the APA.

Methods

This retrospective study evaluated all consecutive patients between October 1998 and January 2010 after either a primary or secondary APA followed by post-repair CMR.

Results

Of 103 patients who had an APA, 31 patients had an analyzable CMR study. The average time to CMR was 24.6 ± 32.5 months post-repair. Echocardiographic findings were confirmed by CMR in 12 patients. There was incomplete imaging by echocardiography in 7 patients and underestimation of pulmonary vein restenosis in 12, when compared to CMR. In total, 19/31 patients (61%) from our cohort had significant stenosis following the APA as assessed by CMR. Our data suggest that at least 18% (19/103) of all patients had significant obstruction post-repair.

Conclusions

Echocardiography incompletely imaged or underestimated the severity of obstruction in patients compared with CMR. Pulmonary vein stenosis remains a sizable complication after repair, even using the APA.  相似文献   
42.
Growing demand for high spatial resolution blood oxygenation level dependent (BOLD) functional magnetic resonance imaging faces a challenge of the spatial resolution versus coverage or temporal resolution tradeoff, which can be addressed by methods that afford increased acquisition efficiency. Spiral acquisition trajectories have been shown to be superior to currently prevalent echo‐planar imaging in terms of acquisition efficiency, and high spatial resolution can be achieved by employing multiple‐shot spiral acquisition. The interleaved spiral in/out trajectory is preferred over spiral‐in due to increased BOLD signal contrast‐to‐noise ratio (CNR) and higher acquisition efficiency than that of spiral‐out or noninterleaved spiral in/out trajectories (Law & Glover. Magn Reson Med 2009; 62:829–834.), but to date applicability of the multishot interleaved spiral in/out for high spatial resolution imaging has not been studied. Herein we propose multishot interleaved spiral in/out acquisition and investigate its applicability for high spatial resolution BOLD functional magnetic resonance imaging. Images reconstructed from interleaved spiral‐in and ‐out trajectories possess artifacts caused by differences in T2* decay, off‐resonance, and k‐space errors associated with the two trajectories. We analyze the associated errors and demonstrate that application of conjugate phase reconstruction and spectral filtering can substantially mitigate these image artifacts. After applying these processing steps, the multishot interleaved spiral in/out pulse sequence yields high BOLD CNR images at in‐plane resolution below 1 × 1 mm while preserving acceptable temporal resolution (4 s) and brain coverage (15 slices of 2 mm thickness). Moreover, this method yields sufficient BOLD CNR at 1.5 mm isotropic resolution for detection of activation in hippocampus associated with cognitive tasks (Stern memory task). The multishot interleaved spiral in/out acquisition is a promising technique for high spatial resolution BOLD functional magnetic resonance imaging applications. Magn Reson Med 70:420–428, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
43.
An infant with hypoplastic left heart syndrome (HLHS) presented with complete heart block and severe myocardial dysfunction requiring ECMO support due to complete left main coronary artery (LMCA) thrombosis. Current guidelines for managing coronary artery thrombosis in infants with single ventricle physiology are inadequate. We describe successful LMCA and branch recanalization via intra coronary infusion of recombinant tissue plasminogen activator and discuss management of acute coronary thrombosis in children with single ventricle physiology.  相似文献   
44.
Myofibroblastoma of the breast is a rare benign mesenchymal tumor. The literature describes relatively few cases of this type of tumor. We report on a new case of myofibroblastoma in a 65-year old man successfully managed at our institution. The purpose of this case report is to highlight characteristics and differential diagnosis of this rare neoplasm.  相似文献   
45.
To characterize posttreatment recurrence of Helicobacter pylori in Peru, 192 adults with H. pylori-positive gastric biopsy specimens were monitored by (14)C-Urea breath test, after eradication of H. pylori by use of amoxicillin, clarithromycin, and omeprazole. The cumulative risk of recurrence at 18 months was 30.3% (95% confidence interval, 21.4%-39.3%). Randomly amplified polymorphic DNA patterns and DNA sequence data established that, among 28 pairs of H. pylori isolates from pretreatment and recurrent infections, 6 (21%) were genetically similar, suggesting recrudescence of the previous infection, and 22 (79%) were different, suggesting reinfection with a new strain that differed from that involved in the initial infection. Eating mainly outside of the home was a risk factor for infection with a new strain (adjusted relative risk [RR], 5.07), whereas older age was a protective factor (adjusted RR, 0.20). Although an increase in the anti-H. pylori IgG antibody titer corresponded to recurrence, pretreatment and recurrent infections were similar with respect to quantitative culture colony counts and histologic characteristics, suggesting that neither prior eradication nor the memory immune response measurably alters the risk or burden of recurrent infection. Although eradication with antibiotics was successful, the high rate of reinfection suggests that treatment is unlikely to have a lasting public health effect in this setting.  相似文献   
46.
Activated pancreatic stellate cells (PSC) play a major role in the development of chronic pancreatitis. Flavonoids (C‐3‐O‐G) theoretically may have potential to suppress activated PSC. The aim of our study was to determine the ability of C‐3‐O‐G to invert synthetic and metabolic activity of alcohol stimulated human pancreatic stellate cells (hPSC). In the present study we demonstrate that treatment with C‐3‐O‐G decreased proliferation rate of ethanol activated hPSC by 51%. Synthesis of extracellular matrix proteins in activated hPSC was markedly inhibited, as shown by reduced levels of collagen I and fibronectin expression. The decrease of secretion of fibronectin by 33% and in collagen I‐25% in ethanol activated and C‐3‐O‐G treated hPSC was observed. Moreover, treatment of ethanol activated hPSC with C‐3‐O‐G resulted in the decrease of oxygen consumption rate by 44% and reduced levels of ATP synthesis (i.e. energy production) by 41%. Hence, the effects of C‐3‐O‐G on ethanol activated hPSC may provide new insights for the use of anthocyanins as anti‐fibrogenic agents in treatment and/or prevention of pancreatic fibrosis. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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The development of transgenic mouse lines that selectively label a subset of neurons provides unique opportunities to study detailed neuronal morphology and morphological changes under experimental conditions. In the present study, a mouse line in which a small number of retinal ganglion cells (RGCs) express yellow fluorescent protein (YFP) under control of the Thy-1 promoter was used (Feng et?al., 2000). We characterized the number, distribution by retinal region and eccentricity of YFP-labeled RGCs using fluorescence microscopy and Stereo Investigator software (MicroBrightField, VT, USA). Then, we captured images of 4-6?YFP-expressing RGCs from each of 8 retinal regions by confocal microscopy, producing 3-dimensional and flattened data sets. A new semi-automated method to quantify the soma size, dendritic length and dendritic arbor complexity was developed using MetaMorph software (Molecular Devices, PA, USA). Our results show that YFP is expressed in 0.2% of all RGCs. Expression of YFP was not significantly different in central versus peripheral retina, but there were higher number of YFP-expressing RGCs in the temporal quadrant than in the nasal. By confocal-based analysis, 58% of RGCs expressing YFP did so at a high level, with the remainder distributed in decreasing levels of brightness. Variability in detailed morphometric parameters was as great between two fellow retinas as in retinas from different mice. The analytic methods developed for this selective YFP-expressing RGC model permit quantitative comparisons of parameters relevant to neuronal injury.  相似文献   
50.
A comparison of the clinical data and those of ECG under physical exercises with the results of coronary angiography is presented for 130 patients with the ischaemic heart disease, aged 28 to 68 years; 63 of them had survived myocardial infarction, 63 had angina of effort, 65--angina at rest and angina of effort, 2 presented no complaints. The comparison of the clinical and coronarographic data demonstrated a high correlation in cases of angina; in 85.3% of the patients with typical angina pectoris coronary angiography revealed anatomic changes in the coronaries. Having compared the data to the positive exercise test with the results of coronary angiography, the authors found that 87.9% of the examined patients have--with a positive exercise test--coronary lesions and the S--T segment depression during physicial exercises 1 mm below the iso-electric line, which permits to diagnose anatomic changes in the coronaries. According to the authors, an acute onset of the disease, a brief history (up to 1 year) and a prompt restoration of the ECG following physical exercises are typical rather for local lesions of one coronary branch.  相似文献   
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