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Sample records for evaluating myocardial anisotropy

  1. High-Resolution Diffusion Tensor MR Imaging for Evaluating Myocardial Anisotropy and Fiber Tracking at 3T: the Effect of the Number of Diffusion- Sensitizing Gradient Directions

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    Choi, Sang Il; Kang, Joon Won; Lim, Tae Hwan [Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Chun, Eun Ju [Seoul National University Bundang Hospital, Sengnam (Korea, Republic of); Choi, Seong Hoon [Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan (Korea, Republic of)

    2010-02-15

    We wanted to evaluate the effect of the number of diffusion-sensitizing gradient directions on the image quality for evaluating myocardial anisotropy and fiber tracking by using in vitro diffusion tensor MR imaging (DT-MRI). The DT-MR images, using a SENSE-based echoplanar imaging technique, were acquired from ten excised porcine hearts by using a 3T MR scanner. With a b-value of 800 s/mm{sup 2}, the diffusion tensor images were obtained for 6, 15 and 32 diffusion-sensitizing gradient directions at the midventricular level. The number of tracked fibers, the fractional anisotropy (FA), and the length of the tracked fibers were measured for the quantitative analysis. Two radiologists assessed the image quality of the fiber tractography for the qualitative analysis. By increasing the number of diffusion-sensitizing gradient directions from 6 to 15, and then to 32, the FA and standard deviation were significantly reduced (p < 0.01), and the number of tracked fibers and the length of the tracked fibers were significantly increased (p < 0.01). The image quality of the fiber tractography was significantly increased with the increased number of diffusion sensitizing gradient directions (p < 0.01). The image quality of in vitro DT-MRI is significantly improved as the number of diffusion-sensitizing gradient directions is increased.

  2. The effect of volume currents due to myocardial anisotropy on body surface potentials

    Science.gov (United States)

    Ramon, Ceon; Schimpf, Paul; Wang, Yanqun; Haueisen, Jens; Ishimaru, Akira

    2002-04-01

    Changes in anterior and posterior body surface potential maps (BSPMs) due to myocardial anisotropy were examined using a highly heterogeneous finite element model of an adult male subject constructed from segmented magnetic resonance images. A total of 23 different tissue types were identified in the whole torso. The myocardial fibre orientations in the human heart wall were mapped from the fibre orientations of a canine heart which are available in the literature using deformable mapping techniques. The current and potential distributions in the whole torso were computed using dipolar sources in the septum, apical area, left ventricular wall or right ventricular wall. For each dipole x, y, z orientations were studied. An adaptive finite element solver was used to compute currents and potential distributions in the whole torso with an element size of 0.78 × 0.78 × 3 mm in the myocardium and larger elements in other parts of the torso. For each dipole position two cases were studied. In one case the myocardium was isotropic and in the other it was anisotropic. It was found that BSPMs showed a very notable difference between the isotropic and the anisotropic myocardium for all dipole positions with the largest difference for the apical dipoles. The correlation coefficients for the BSPMs between the isotropic and anisotropic cases ranged from 0.83 for an apical dipole to 0.99 for an RV wall dipole. These results suggest that myocardial fibre anisotropy plays an important role in determining the body surface potentials.

  3. Curve Distance Measure for Quantitative Evaluation of Myocardial Boundary Tracking

    OpenAIRE

    Adhi Harmoko Saputro; Mohd Marzuki Mustafa; Aini Hussain

    2012-01-01

    Myocardial boundary tracking is part of feature extraction task for evaluating human cardiac abnormalities. In this case, the feature of myocardial contraction is extracted in the form of the boundary shape movement and alteration such as shape motion, shape deformation. In this paper, a curve distance measure is proposed for evaluating performance of myocardial boundary tracking techniques. The curve is constructed of 9 – 14 control points along the myocardial boundary which is tracked to ...

  4. Evaluate the early changes of myocardial fibers in rhesus monkey during sub-acute stage of myocardial infarction using diffusion tensor magnetic resonance imaging.

    Science.gov (United States)

    Wang, Yuqing; Cai, Wei; Wang, Lei; Xia, Rui

    2016-05-01

    The deterioration of cardiac mechanical function starts from the micro-alterations in the myocardial fibers after myocardial infarction (MI) due to the heart beats derived from the systole and diastole of the myocardial fibers. So, we want to evaluate quantitatively the early changes of myocardial fibers in rhesus monkey during sub-acute MI stage. Three fixed hearts with infarction after left anterior descending coronary artery ligation for 7days and eight age-matched intact controls were scanned by ex-vivo diffusion tensor magnetic resonance imaging (DT-MRI) to measure apparent diffusion coefficient (ADC), fractional anisotropy (FA) and helix angle (HA). In comparison with healthy controls, FA and transmural range of HA in MI regions showed a significant reduction whereas ADC showed a significant increment (pmyocardial fibers shifted further to left-handed helix around the infarcted and adjacent myocardium but shifted further to right-handed helix in remote myocardium. HA is sensitive to evaluate quantitatively the early changes of myocardial fibers in sub-acute MI rhesus monkeys. The myocardial fibers in normal monkeys are similar to those in normal humans, suggesting that early changes of myocardial fibers in sub-acute MI monkeys can contribute to more accurately understand those in patients suffering sub-acute MI. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Evaluation of electrical resistivity anisotropy in geological mapping ...

    African Journals Online (AJOL)

    user

    However, the combination of the anisotropy polygons and the iso-resistivity map has reduced the ambiguity inherent in using a single geophysical parameter. Key words: Electrical resistivity anisotropy, radial vertical electrical sounding, anisotropy polygons. INTRODUCTION. The geological mapping in the Precambrian, ...

  6. Evaluation of myocardial abnormalities in patients with collagen diseases by thallium-201 myocardial scintigram

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    Yamano, Shigeru (Nara Medical Univ., Kashihara (Japan))

    1992-08-01

    This study was performed to evaluate myocardial lesions in patients with collagen diseases by rest and exercise thallium-201 myocardial scintigraphies. A total of 76 patients without ischemic ECG changes, consisting of 27 cases of systemic lupus erythematosus (SLE), 17 cases of polymyositis or dermatomyositis (PM[center dot]DM), 11 cases of progressive systemic sclerosis (PSS), and 21 cases of Sjoegren's syndrome (SjS), were enrolled in this study. Reversible exercise-induced defects suggesting myocardial ischemia were noted in 12 cases of SLE, 5 cases of PM[center dot]DM, 3 cases of PSS, and 3 cases of SjS. Of the 23 patients who had exercise-induced defects, 9 patients showed normal coronary angiograms by cardiac catheterization. Fixed hypoperfusion areas were observed in 5 cases of SLE, 6 cases of PM[center dot]DM, 4 cases of PSS and 3 cases of SjS. Rest thallium-201 myocardial scintigraphy disclosed hypoperfusion areas, which were not induced by exercise, in 1 case of SLE, 4 cases of PM[center dot]DM, 1 case of PSS and 5 cases of SjS. Endomyocardial biopsy was performed on 20 patients. Myocardial lesions in PM[center dot]DM and PSS were more severe and wide spread than in SLE. Ejection fraction and fractional shortening evaluated by echocardiography had no significant differences between each disease group and the healthy control group. These findings suggest that patients with collagen diseases show the presence of abnormalities of coronary circulation at the level of the intramyocardial vasculature in the stage before impairment of cardiac function, myocardial fibrosis and functional abnormalities of the cell membrane level that were not dependent on myocardial ischemia. (author).

  7. Evaluation of myocardial abnormalities in collagen diseases by thallium-201 myocardial scintigraphy

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    Yamano, Shigeru; Kagoshima, Tadashi; Sugihara, Kiyotaka (Nara Medical Univ., Kashihara (Japan)) (and others)

    1993-12-01

    This study was performed to evaluate myocardial abnormalities in patients with collagen diseases by exercise and rest thallium-201 myocardial scintigrams. A total of 65 patients without ischemic ECG changes, consisting of 18 with systemic lupus erythematosus (SLE), 18 with polymyositis (PM), 8 with progressive systemic sclerosis (PSS), and 21 with Sjoegren's syndrome (SjS), was enrolled in this study. Reversible exercise-induced defects scintigraphically suggesting myocardial ischemia were noted in 8 cases of SLE, 4 cases of PM, 4 cases of PSS, and 3 cases of SjS. Nineteen patients had exercise-induced defects and underwent cardiac catheterization, 8 of whom had normal coronary angiograms. Fixed hypoperfusion areas were observed in one case of SLE, 6 cases of PM and 3 cases of SjS. Rest thallium-201 myocardial scintigram disclosed hypoperfusion areas which were not induced by exercise in 2 cases of SLE, 3 cases of PM, one case of PSS and 5 cases of SjS. Echocardiogram showed no significant differences in ejection fraction and % fractional shortening between the disease groups and healthy control group. These findings suggest that patients with collagen diseases have abnormalities of coronary circulation at the level of the intramural vasculature before cardiac function impairment, myocardial fibrosis and functional abnormalities at the cell membrane. (author).

  8. Evaluation of myocardial damage in Duchenne's muscular dystrophy with thallium-201 myocardial SPECT

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    Tamura, Takuhisa; Shibuya, Noritoshi (Kawatana National Hospital, Nagasaki (Japan)); Hashiba, Kunitake; Oku, Yasuhiko; Mori, Hideki; Yano, Katsusuke

    1993-01-01

    Myocardial damage and cardiopulmonary functions in patients with Duchenne's muscular dystrophy (DMD) were assessed using thallium-201 myocardial single-photon emission computed tomography (SPECT) and technetium-99m multigated radionuclide angiography. Twenty-five patients with DMD were divided into 4 groups according to percent of perfusion defect (%PD) calculated by the bull's-eye method and age. PD was detected in 24 (96.0%) of 25 patients with DMD, and it spread from the left ventricular lateral wall to the anterior wall and/or interventricular septum. PD was detected even in a 6-year-old DMD boy. Patients in Group I (%PD[>=]10% and age<15 years old) were shown to have a higher risk of left-sided heart failure without respiratory failure. Patients in Group II (%PD[>=]10 and age[>=]15) showed decreased pulmonary function and worsened arterial blood gas values as compared with Group IV (%PD<10 and age[>=]15). There was no significant difference in cardiac function among the 4 groups. It is postulated that myocardial damage in Group II patients is dependent primarily on a deficiency of dystrophin and on chronic respiratory failure, and that some of them are at risk of cardiopulmonary failure. It is concluded that myocardial SPECT is useful for the early diagnosis of myocardial damage and evaluation of cardiopulmonary function in DMD patients. (author).

  9. A Computational Scheme To Evaluate Hamaker Constants of Molecules with Practical Size and Anisotropy.

    Science.gov (United States)

    Hongo, Kenta; Maezono, Ryo

    2017-11-14

    We propose a computational scheme to evaluate Hamaker constants, A, of molecules with practical sizes and anisotropies. Upon the increasing feasibility of diffusion Monte Carlo (DMC) methods to evaluate binding curves for such molecules to extract the constants, we discussed how to treat the averaging over anisotropy and how to correct the bias due to the nonadditivity. We have developed a computational procedure for dealing with the anisotropy and reducing statistical errors and biases in DMC evaluations, based on possible validations on predicted A. We applied the scheme to cyclohexasilane molecule, Si 6 H 12 , used in "printed electronics" fabrications, getting A ≈ 105 ± 2 zJ, being in plausible range supported even by other possible extrapolations. The scheme provided here would open a way to use handy ab initio evaluations to predict wettabilities as in the form of materials informatics over broader molecules.

  10. [Evaluating work capacity after myocardial infarct].

    Science.gov (United States)

    Mende, W

    1997-02-01

    Work resumption of patients after myocardial infarction is primarily dependent on left-ventricular function, stress-related ischemia and rhythm-disturbances, additionally the general physical and psychological state play an important role. -The basic examination includes not only the history and physical examination, but also resting ECG, ECG exercise testing, 2-dimensional echocardiogramm and Holter-ECG. Additionally, stress-echocardiogramm, nuclear exercise testing and invasive procedures can be necessary. It is possible to estimate the work-capacity of the patient by classifying the ECG testing and by regarding further details of the disease. The return-to-work-rate does not only depend on the severity of a CHD, but also on the age, education, social class, high physical activity during work, job related satisfaction, family situation and available suitable jobs on the labor market.

  11. Evaluation of myocardial ischemia by multiple detector computed tomography

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    Fernandes, Fabio Vieira, E-mail: rccury@me.com [Hospital do Coracao (HCor), Sao Paulo, SP (Brazil); Cury, Roberto Caldeira [Hospital Samaritano, Sao Paulo, SP (Brazil)

    2015-01-15

    For years, cardiovascular diseases have been the leading cause of death worldwide, bringing on important social and economic consequences. Given this scenario, the search for a method capable of diagnosing coronary artery diseases in an early and accurate way is increasingly higher. The coronary computed tomography angiogram is already widely established for the stratification of coronary artery diseases, and, more recently, the computed tomography myocardial perfusion imaging has been providing relevant information by correlating ischemia and the coronary anatomy. The objective of this review is to describe the evaluation of myocardial ischemia by multiple detector computed tomography. This study will resort to controlled clinical trials that show the possibility of a single method to identify the atherosclerotic load, presence of coronary artery luminal narrowing and possible myocardial ischemia, by means of a fast, practical and reliable method validated by a multicenter study. (author)

  12. The incomplete bucindolol evaluation in acute myocardial infarction Trial (BEAT)

    DEFF Research Database (Denmark)

    Torp-Pedersen, Christian; Køber, Lars; Ball, Stephen

    2002-01-01

    The aim of this study was to evaluate the efficacy of adding the beta-blocker bucindolol to standard therapy shortly after a myocardial infarction in a high-risk population with reduced left ventricular function. METHODS: The study was planned to include 2000 patients with an enzyme confirmed...... myocardial infarction and severely reduced left ventricular function determined by echocardiography (corresponding to ejection fraction ... of bucindolol 0.88 (95% confidence limits 0.5-1.5; P=0.6). There were 9/4 (bucindolol/placebo, P=0.16) heart failure events and 5/17 (P=0.01) reinfarctions in the bucindolol/placebo groups. CONCLUSION: Due to early closure it is unknown whether bucindolol changes mortality in high-risk post myocardial infarct...

  13. Crustal anisotropy contribution under-evaluated under Tibet ?

    Science.gov (United States)

    Herquel, G.; Edme, P.

    2003-04-01

    Moho P-to-S converted phases may be used to determine the complete crustal component of anisotropy. Phases with a good signal-to-noise ratio and with sufficient azimuthal coverage are required to avoid misleading results. Previous results may be low estimates of this contribution in Tibet (0.15-0.3s) since some very large mantellic delays have been observed in other areas of the plateau. New measurements use data from stations with the largest mantellic delays δt observed in Tibet: at least 2 seconds (stations ST17, ST18 and ST19 from Indepth III and BUDO). As the data for station BUDO was good enough , we compare results obtained by original signals and by single receiver functions obtained in the frequency domain or by iterative deconvolution. The data were processed using waveform rotation-correlation, tangential energy minimization and particle motion analysis methods. The results are remarkably coherent concerning the fast polarization direction and the mean delay value using these different techniques. Using receiver function stacked data in different bins of backazimuth we obtained delay values in good agreement with the other techniques and hence the processing can be accelerated using this approach. At all 4 stations a mean value of delay of 0.15s is retrieved with an uncertainty of 0.05s: no single value exceed 0.3s. These new results are similar to the first estimations in Tibet and confirm the results obtained in other aeras (Ural Montains, New Zealand and Basin and Range). Finally, we observe also a good correlation with the fast polarization direction obtained by teleseismic shear wave analysis.

  14. Evaluation of the Differences of Myocardial Fibers between Acute and Chronic Myocardial Infarction: Application of Diffusion Tensor Magnetic Resonance Imaging in a Rhesus Monkey Model

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    Wang, Yuqing [Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041 (China); CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, National Center for Nanoscience and Technology of China, Beijing 100190 (China); Cai, Wei [Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041 (China); Department of Radiology, Beijing Jishuitan Hospital, 4th Clinical Medical College of Peking University, Beijing 100035 (China); Wang, Lei [Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041 (China); Xia, Rui [Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041 (China); Department of Radiology, The First Affiliated Hospital, Chongqing Medical University, Chongqing 400016 (China); Chen, Wei [Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041 (China); Department of Radiology, The First Affiliated Hospital of Kunming Medical University, Yunnan 650032 (China); Zheng, Jie [Mallinckrodt Institute of Radiology, School of Medicine, Washington University, St. Louis, MO 63110 (United States); Gao, Fabao [Department of Radiology, West China Hospital, Sichuan University, Sichuan 610041 (China)

    2016-11-01

    To understand microstructural changes after myocardial infarction (MI), we evaluated myocardial fibers of rhesus monkeys during acute or chronic MI, and identified the differences of myocardial fibers between acute and chronic MI. Six fixed hearts of rhesus monkeys with left anterior descending coronary artery ligation for 1 hour or 84 days were scanned by diffusion tensor magnetic resonance imaging (MRI) to measure apparent diffusion coefficient (ADC), fractional anisotropy (FA) and helix angle (HA). Comparing with acute MI monkeys (FA: 0.59 ± 0.02; ADC: 5.0 ± 0.6 × 10{sup -4} mm{sup 2}/s; HA: 94.5 ± 4.4°), chronic MI monkeys showed remarkably decreased FA value (0.26 ± 0.03), increased ADC value (7.8 ± 0.8 × 10{sup -4}mm{sup 2}/s), decreased HA transmural range (49.5 ± 4.6°) and serious defects on endocardium in infarcted regions. The HA in infarcted regions shifted to more components of negative left-handed helix in chronic MI monkeys (-38.3 ± 5.0°–11.2 ± 4.3°) than in acute MI monkeys (-41.4 ± 5.1°–53.1 ± 3.7°), but the HA in remote regions shifted to more components of positive right-handed helix in chronic MI monkeys (-43.8 ± 2.7°–66.5 ± 4.9°) than in acute MI monkeys (-59.5 ± 3.4°–64.9 ± 4.3°). Diffusion tensor MRI method helps to quantify differences of mechanical microstructure and water diffusion of myocardial fibers between acute and chronic MI monkey's models.

  15. Evaluation of the differences of myocardial fibers between acute and chronic myocardial infarction: Application of diffusion tensor magnetic resonance imaging INA Rhesus monkey model

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yu Qing; Cai, Wei; Wang, Lei; Xia, Rui; Chen, Wei; Zheng, Jie [Dept. of Radiology, West China Hospital, Sichuan University, Sichuan (China); Gao, Fabao [Mallinckrodt Institute of Radiology, School of Medicine, Washington University, St. Louis (United States)

    2016-09-15

    To understand microstructural changes after myocardial infarction (MI), we evaluated myocardial fibers of rhesus monkeys during acute or chronic MI, and identified the differences of myocardial fibers between acute and chronic MI. Six fixed hearts of rhesus monkeys with left anterior descending coronary artery ligation for 1 hour or 84 days were scanned by diffusion tensor magnetic resonance imaging (MRI) to measure apparent diffusion coefficient (ADC), fractional anisotropy (FA) and helix angle (HA). Comparing with acute MI monkeys (FA: 0.59 ± 0.02; ADC: 5.0 ± 0.6 × 10{sup -4} mm{sup 2}/s; HA: 94.5 ± 4.4°), chronic MI monkeys showed remarkably decreased FA value (0.26 ± 0.03), increased ADC value (7.8 ± 0.8 × 10{sup -4} mm{sup 2}/s), decreased HA transmural range (49.5 ± 4.6°) and serious defects on endocardium in infarcted regions. The HA in infarcted regions shifted to more components of negative left-handed helix in chronic MI monkeys (-38.3 ± 5.0°–11.2 ± 4.3°) than in acute MI monkeys (-41.4 ± 5.1°–53.1 ± 3.7°), but the HA in remote regions shifted to more components of positive right-handed helix in chronic MI monkeys (-43.8 ± 2.7°–66.5 ± 4.9°) than in acute MI monkeys (-59.5 ± 3.4°–64.9 ± 4.3°). Diffusion tensor MRI method helps to quantify differences of mechanical microstructure and water diffusion of myocardial fibers between acute and chronic MI monkey's models.

  16. Evaluation of myocardial bridging by coronary computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Barros, Marcio Vinicius Lins; Rabelo, Daniel Rocha; Siqueira, Maria Helena Albernaz, E-mail: marciovlbarros@uol.com.br [Hospital Mater Dei, Belo Horizonte, MG (Brazil); Garretto, Luiza Samarane; Paula, Marcela Mascarenhas De; Carvalho, Marina Oliveira; Alves, Marina Rangel Moreira Barros [Faculdade de Saude e Ecologia Humana (FASEH), Vespasiano, MG (Brazil)

    2013-01-15

    The myocardial bridge (MB) is defined as a segment of an epicardial coronary artery that has an intramural course in the myocardium. Although MB is clinically silent in most cases, has been associated with myocardial ischemia, arrhythmias and sudden death. Coronary conventional angiography is the gold standard for detection of MB, but is invasive and cannot be sufficiently sensitive compared to autopsy studies. Recently, multislice computed tomography of coronary arteries (MCTCA) has allowed the detection of coronary artery course, including PM. Objectives: to evaluate MB prevalence in patients with suspected coronary artery disease undergoing MCTCA and to evaluate the predictive value of this method at medium term. Methods: during the period 2008 to 2011, 498 consecutive patients were examined by TMC for the diagnosis of coronary artery disease, being conducted to evaluate the presence of BM and followed for a mean follow-up of 23 months for the occurrence of cardiovascular hard events (death, hospitalization or revascularization). Results: patients mean age was 55.3 ± 14.2, being male 71.1%. Among the patients, 7.6% (38 patients) showed MB. Main findings included angina pectoris in 40% and a positive stress test in 34%. 34.2% had atherosclerotic disease, and one patient had significant coronary stenosis. During follow-up, no patients showed adverse events. Conclusion: MCTCA is a noninvasive technique with high accuracy in anatomical evaluation of the coronary arteries and may be particularly useful to assess the incidence, location and morphology of myocardial bridging in vivo. (author)

  17. Exercise myocardial perfusion scintigraphy is useful for evaluating myocardial ischemia even in the elderly

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    Kurata, Chinori; Uehara, Akihiko; Sugi, Toshihiko; Yamazaki, Keisuke [Hamamatsu Univ. School of Medicine, Shizuoka (Japan); Tawarahara, Kei; Mikami, Tadashi; Matoh, Fumitaka; Odagiri, Keiichi

    2000-06-01

    Pharmacologic stress testing is recommended to elderly patients as a valuable alternative to exercise testing. We examined whether exercise testing is as useful for evaluating myocardial ischemia in the elderly as in the young. The consecutive 1,508 patients who underwent exercise {sup 201}Tl single-photon emission computed tomography (SPECT) were divided into six age groups: 6-29 years (n=56), 30-44 (n=143), 45-54 (n=311), 55-64 (n=498), 65-74 (n=402), and 75-88 (n=98). Both heart rate and rate-pressure product at peak exercise were significantly lower in patients aged 75-88 than in the other five groups. The frequency of ischemic ST depression was higher in patients aged 75-88 than in those aged 6-74, although the difference was not significant. Moreover, the frequency of {sup 201}Tl transient defect was significantly higher in patients aged 75-88 than in those aged 6-74. On the other hand, the sensitivity of ischemic ST depression for {sup 201}Tl transient defect was similar among the six groups, but the specificity was significantly lower in patients aged 75-88 than in those aged 6-74. In conclusion, exercise {sup 201}Tl SPECT is useful for evaluating myocardial ischemia even in the elderly, but exercise electrocardiography has limitations such as lower specificity in the elderly than {sup 201}Tl SPECT. (author)

  18. Myocardial bridging: evaluation with multislice computed tomography coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Barros, M.V.L. de; Rabelo, D.R.; Nunes, M.C.P.; Siqueira, M.H.A. [Mater Dei Hospital, Belo Horizonte, MG (Brazil)

    2012-04-15

    Myocardial bridging (MB) is defined as a segment of a major epicardial coronary artery that proceeds intramurally through the myocardium beneath the muscle bridge. Although MB is clinically silent in most cases, it has been associated with myocardial ischemia, myocardial infarction, arrhythmia, and sudden death. Conventional coronary angiography (CCA) is the gold standard for detection, but it is invasive and may not be sensitive enough to detect a thin bridge. Recently, multislice computed tomography coronary angiography (MCTCA) have made possible the clear detection of the entire running courses of coronary arteries and the MB itself. Objective: To evaluate the prevalence MB in patients suspect to coronary artery disease submitted to MCTCA and assessing the predictive value of this method in the midterm. Methods: 498 consecutive patients were examined by MCTCA for the diagnosis of coronary artery disease and followed for a mean follow-up of 17 months for the occurrence of cardiovascular events (death, hospitalization and / or revascularization myocardial). Results: The mean age of patients was 58.4 ± 12.5 years old, 74.3% male. Among the patients, 6,02% (30 patients) showed MB. The major indications were angina pectoris in 45,8% and positive stress testing in 33,3%. 62,5% showed absent atherosclerotic disease and only 1 patient showed moderade descending anterior stenosis. During the follow-up none patient showed hard events. Conclusion: Patients with MB could present with angina pectoris and positive stress testing and showed midterm excellent prognosis. MCTCA is an alternative noninvasive imaging tool that allows for easy and accurate evaluation of MB.

  19. Evaluation of myocardial sympathetic nerve function in patients with mitral valve prolapse using iodine-123-metaiodobenzylguanidine myocardial scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Kishi, Fumiko; Nomura, Masahiro; Yukinaka, Michiko [Tokushima Univ. (Japan). School of Medicine] [and others

    1996-06-01

    Mitral valve prolapse (MVP) is closely related to myocardial sympathetic nerve function. This study evaluated the presence of impaired myocardial sympathetic nerve function by Iodine-123-metaiodobenzylguanidine (MIBG) scintigraphy in nine patients with MVP. For comparison, 15 healthy subjects without heart disease were investigated (control group). Single photon emission computed tomography (SPECT) and anterior planar myocardial scintigraphy were performed 15 min (initial images) and 3 hours (delayed images) after injection of MIBG (111 MBq). The location and degrees of reduced tracer uptake were evaluated. Myocardial MIBG uptake was quantified by uptake ratio of the heart (H) to upper mediastinum (M) on the anterior planar images (H/M). Percentage washout of MIBG in nine sectors of all oblique slices along the short-axis was calculated. The washout rates were higher at the inferoposterior and septal segments in patients with anterior leaflet prolapse, and at inferoposterior and lateral segments in patients with posterior leaflet prolapse. The bull`s eye map showed increased washout rate in the apical and posteroseptal basal segments. There was no significant difference in the H/M ratio between MVP patients and the control group. These results indicate that MIBG can be used to evaluate localized myocardial sympathetic nerve function in MVP. (author)

  20. Discrepancy between myocardial perfusion and fatty acid metabolism following acute myocardial infarction for evaluating the dysfunctional viable myocardium.

    Science.gov (United States)

    Biswas, Shankar K; Sarai, Masayoshi; Toyama, Hiroshi; Hishida, Hitoshi; Ozaki, Yukio

    2012-01-01

    Following acute myocardial infarction (AMI) the area of myocardial perfusion and metabolism mismatch is designated as dysfunctional viable myocardium. (123)I-beta-methyl iodophenyl pentadecanoic acid (BMIPP) is clinically very useful for evaluating myocardial fatty acid metabolism, and (99)mTc-Tetrofosmin (TF) is a widely used tracer for myocardial perfusion. This study was designed to evaluate the degree of discrepancy between BMIPP and TF at the subacute state of AMI. Fifty-two patients (aged 59 ± 10 years; mean 46 years) with AMI were enrolled, and all of them underwent percutaneous coronary intervention (PCI). Patients were classified according to ST-T change and PCI timing. (123)I-beta-methyl iodophenyl pentadecanoic acid and TF cardiac scintigraphy were performed on 7 ± 3.5 days of admission using a dual headed gamma camera. Perfusion and fatty acid metabolism defect were scored on a 17 segments model. The mean BMIPP defect score on early and delayed images were 16.67 ± 10.19 and 16.25 ± 10.40, respectively. The mean TF defect score was 10 ± 7.69. Defect score of BMIPP was significantly higher than that of the TF (P TF), and 5 (10%) patients showed matched defect (BMIPP = TF). Mismatched defect score (MMDS) was significantly higher in patients with ST-segment elevation myocardial infarction (STEMI) than that of non-ST-segment elevation myocardial infarction (NSTEMI) (P < 0.041; 95% CI 0.11-5.19). At the subacute state of AMI, most of the patients showed perfusion-metabolism mismatch, which represents the dysfunctional viable myocardium, and patients with STEMI showed higher mismatch. Copyright © 2012 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.

  1. Evaluation of BRDF Archetypes for Representing Surface Reflectance Anisotropy Using MODIS BRDF Data

    Directory of Open Access Journals (Sweden)

    Hu Zhang

    2015-06-01

    Full Text Available Bidirectional reflectance distribution function (BRDF archetypes extracted from the Moderate Resolution Imaging Spectroradiometer (MODIS BRDF/Albedo product over the global Earth Observing System Land Validation Core Sites can be used to simplify BRDF models. The present study attempts to evaluate the representativeness of BRDF archetypes for surface reflectance anisotropy. Five-year forward-modeled MODIS multi-angular reflectance (MCD-ref and aditional actual MODIS multi-angular observations (MCD-obs in four growing periods in 2008 over three tiles were taken as validation data. First, BRDF archetypes in the principal plane were qualitatively compared with the time-series MODIS BRDF product of randomly sampled pixels. Secondly, BRDF archetypes were used to fit MCD-ref, and the average root-mean-squared errors (RMSEs over each tile were examined for these five years. Finally, both BRDF archetypes and the MODIS BRDF were used to fit MCD-obs, and the histograms of the fit-RMSEs were compared. The consistency of the directional reflectance between the BRDF archetypes and MODIS BRDFs in nadir-view, hotspot and entire viewing hemisphere at 30° and 50° solar geometries were also examined. The results confirm that BRDF archetypes are representative of surface reflectance anisotropy for available snow-free MODIS data.

  2. Myocardial bridging as evaluated by 16 row MDCT

    Energy Technology Data Exchange (ETDEWEB)

    Canyigit, Murat [Hacettepe University, Faculty of Medicine, Department of Radiology, Sihhiye, 06100 Ankara (Turkey)], E-mail: mcanyigit@yahoo.com; Hazirolan, Tuncay; Karcaaltincaba, Musturay; Dagoglu, Merve Gulbiz; Akata, Deniz [Hacettepe University, Faculty of Medicine, Department of Radiology, Sihhiye, 06100 Ankara (Turkey); Aytemir, Kudret; Oto, Ali [Hacettepe University, Faculty of Medicine, Department of Cardiology, Sihhiye, 06100 Ankara (Turkey); Balkanci, Ferhun; Akpinar, Erhan; Besim, Aytekin [Hacettepe University, Faculty of Medicine, Department of Radiology, Sihhiye, 06100 Ankara (Turkey)

    2009-01-15

    Purpose: The purpose of this study is to find out the prevalence, appearance and clinical symptoms of myocardial bridging (MB) by MDCT coronary angiography (CTA). Materials and methods: A total of 280 (50 females) consecutive patients followed with coronary artery disease or postoperative stent and bypass control, underwent CTA performed by 16-MDCT scanner between January 2006 and April 2006. Short axis multiplanar reformatted images were evaluated. MBs were classified as complete and incomplete bridges with respect to continuity of the myocardium over the tunneled segment of left anterior descending artery (LAD) in interventricular groove and the cut-off value is 1.3 mm. Patients diagnosed with MB on CTA who had prior catheter angiography studies were re-evaluated for the presence of MB. Results: One hundred and twenty MBs [98 (81.6%) on LAD, 2 (1.6%) on diagonal branch, 11 (9.1%) on obtuse marginal, 4 (3.3%) on right coronary artery, 5 (4.1%) on ramus intermedius artery] were detected in 108 (38.5%) patients. Eighty-five (70.8%) of bridged segments in 79 (28.2%) patients were complete and the rest [35 (29.2%) in 34 (12.1%) patients] were incomplete. In 12 patients two MBs (either on different arteries or on the same artery) were detected. The length of bridged segments in patients with complete and incomplete MBs varied between 4-50.9 mm (mean 18 mm) and 4-37.3 mm (mean 13.6 mm), respectively, and the depth of myocardium over the artery ranged between 1-6.4 mm (mean 2.3 mm) and 1-1.2 mm (mean 1 mm), respectively. Thirty (27.7%) out of 108 patients, in whom MB was detected on CTA, were found to have correlative catheter angiography studies, retrospectively and MB was detected only in 4 (13.3%) out of 30 patients. Conclusion: MDCT coronary angiography is a non-invasive, efficient method in the diagnosis of MB avoiding the procedural risks that catheter angiography carries. MDCT coronary angiography allows direct visualization of the bridge itself and may thus give

  3. Quantitative evaluation of myocardial function by a volume-normalized map generated from relative blood flow

    Energy Technology Data Exchange (ETDEWEB)

    Fukami, Tadanori [Department of Bio-system Engineering, Faculty of Engineering, Yamagata University, Yonezawa, Yamagata 992-8510 (Japan); Sato, Hidenori [Department of Bio-system Engineering, Faculty of Engineering, Yamagata University, Yonezawa, Yamagata 992-8510 (Japan); Wu, Jin [Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki 305-8575 (Japan); Lwin, Thet-Thet- [Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki 305-8575 (Japan); Yuasa, Tetsuya [Department of Bio-system Engineering, Faculty of Engineering, Yamagata University, Yonezawa, Yamagata 992-8510 (Japan); Kawano, Satoru [Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki 305-8575 (Japan); Iida, Keiji [Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki 305-8575 (Japan); Akatsuka, Takao [Department of Bio-system Engineering, Faculty of Engineering, Yamagata University, Yonezawa, Yamagata 992-8510 (Japan); Hontani, Hidekata [Department of Computer Science and Engineering, Nagoya Institute of Technology, Aichi 466-8555 (Japan); Takeda, Tohoru [Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki 305-8575 (Japan); Tamura, Masao [Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki 305-8575 (Japan); Yokota, Hiroshi [Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki 305-8575 (Japan)

    2007-07-21

    Our study aimed to quantitatively evaluate blood flow in the left ventricle (LV) of apical hypertrophic cardiomyopathy (APH) by combining wall thickness obtained from cardiac magnetic resonance imaging (MRI) and myocardial perfusion from single-photon emission computed tomography (SPECT). In this study, we considered paired MRI and myocardial perfusion SPECT from ten patients with APH and ten normals. Myocardial walls were detected using a level set method, and blood flow per unit myocardial volume was calculated using 3D surface-based registration between the MRI and SPECT images. We defined relative blood flow based on the maximum in the whole myocardial region. Accuracies of wall detection and registration were around 2.50 mm and 2.95 mm, respectively. We finally created a bull's-eye map to evaluate wall thickness, blood flow (cardiac perfusion) and blood flow per unit myocardial volume. In patients with APH, their wall thicknesses were over 10 mm. Decreased blood flow per unit myocardial volume was detected in the cardiac apex by calculation using wall thickness from MRI and blood flow from SPECT. The relative unit blood flow of the APH group was 1/7 times that of the normals in the apex. This normalization by myocardial volume distinguishes cases of APH whose SPECT images resemble the distributions of normal cases.

  4. Evaluation of Stress Anisotropy and Shearing Stress Using an Eddy Current Method with a Tangential-Rectangular Coil

    Science.gov (United States)

    Sekine, Yuichi; Soyama, Hitoshi

    In establishing a system to evaluate residual stress, it is important to design the system so that it can also evaluate the stress anisotropy, since this is introduced into metallic materials by surface processes such as grinding and polishing. The shearing stress is also an important parameter when the shear strength has to be considered, since tensile stress can cause stress corrosion cracking. Thus, a method to nondestructively evaluate the stress anisotropy and shearing stress in a short time is required. In this paper, a nondestructive eddy current method using a tangential-rectangular coil was used to accomplish this. The material under test was stainless steel, Japanese Industrial Standard (JIS) SUS316L, ground or polished by an angle grinder. The stress anisotropy caused by the grinding and polishing processes was evaluated by the eddy current method with the tangential-rectangular coil. To vary the stress state, some specimens were treated with cavitation peening after grinding with the angle grinder. The results demonstrate that the stress anisotropy, shearing stress and peening intensity can be evaluated by the eddy current method using the tangential-rectangular coil. From the results, it was concluded that the maximum shearing stress and the direction of the principal stress could be determined.

  5. EVALUATION OF SERUM ALBUMIN LEVELS IN ACUTE MYOCARDIAL INFARCTION

    Directory of Open Access Journals (Sweden)

    Shilpa

    2015-10-01

    Full Text Available BACKGROUND : Acute myocardial infarction (AMI is one of the major causes of mortality and morbidity in the world. Serum albumin levels are inversely related with age, smoking, blood pressure and obesity. It is not clear whether low serum albumin level is a nonspecific , prognostic variable, a marker of subclinical disease, or whether it is a part of causal mechanism leading to death due to cardiovascular disease. Some studies have reported an inverse association between serum albumin and cardiovascular mortality but oth ers have not . 1 The association between serum albumin and cardiovascular mortality remains controversial. This study was done to evaluate the serum albumin levels in patients with ST segment elevation Myocardial infarction (STEMI over a period of three days from the date of admission and whether the changes had any relationship with the prognosis of the patient. AIM: to associate changes in serum albumin levels in AMI patients over a period of three days i.e., day zero - at the time of admission, day+1 - the following day(12 to 30hrs after collecting first sample, day +2(32 to 54 hrs after collecting first sample with the clinical prognosis of the patient. SETTINGS AND DESIGN : Prospective follow up study in patents admitted with AMI in a tertiary care hospital. METHODS: 30 pati ents admitted with STEMI were included in the study and serum albumin levels were estimated in them on admission and for two days thereafter. Statistical analysis used. The data was analysed using SPSS 15.0, STATA 8.0, MEDLAC 9.0.1, And SYSTAT 11 softwares. Repeated measures analysis of variance and student t test was used to find the significance in changes of serum albumin levels and prognosis of the patient on different days. RESULTS AND CONCLUSION: This study found that there was fall in serum albumin le vels in patients with AMI in the course of three days compared with the day of admission and it was significantly associated with bad prognosis.

  6. Evaluation of the membrane attack complex of complement for the detection of a recent myocardial infarction in man

    NARCIS (Netherlands)

    Robert-Offerman, S. R.; Leers, M. P.; van Suylen, R. J.; Nap, M.; Daemen, M. J.; Theunissen, P. H.

    2000-01-01

    The diagnosis of an acute myocardial infarction (MI) can be cumbersome for pathologists. Even with a positive nitroblue tetrazolium (NBT) reaction, haematoxylin and eosin (H&E) evaluation of the myocardial tissue can remain inconclusive. Early signs presumed diagnostic for myocardial infarction,

  7. GATED SPECT TO EVALUATE LEFT VENTRICULAR MYOCARDIAL PERFUSION, FUNCTION AND DYSSYNCHRONY FOR RESYNCHRONIZATION THERAPY

    Directory of Open Access Journals (Sweden)

    E.N. Ostroumov

    2009-01-01

    Full Text Available The study included 15 consecutive patients with heart failure and substantial LV dyssynchrony undergoing CRT. Clinical and phase analysis of gated myocardial perfusion SPECT assessed at baseline, after 2–3 days and after 3–4 months of CRT. The results demonstrated inversely relationship between the response to CRT and the nonviable myocardium. Evaluation of myocardial viability is necessary to considered in the selection process for CRT.

  8. Hypercholesterolemia and Myocardial function evaluated via Tissue Doppler Imaging

    Directory of Open Access Journals (Sweden)

    Kotaru Pavan

    2009-11-01

    Full Text Available Abstract Objective To establish a link between hypercholesterolemia and myocardial dysfunction. Background Heart failure is a complex disease involving changes in systolic and diastolic function. Newer echocardiographic imaging modalities may be able to detect discreet changes in myocardial function associated with hypercholesterolemia. Therefore we sought to establish a link between hypercholesterolemia and myocardial dysfunction with tissue Doppler imaging (TDI. Methods Twenty-seven rabbits were studied: 7 were fed normal chow (group 1 and 20 a high cholesterol diet (10 with ezetimibe, 1 mg/kg/day; group 2 and 10 without, group 3. Echocardiographic images were obtained under general anesthesia. Serum cholesterol levels were obtained at baseline, 3 and 6 months and myocardial cholesterol levels measured following euthanasia. Results Doppler measurements, including E/A, E'/A' and S' were significantly lower in group 3 compared to both groups 1 and 2 but no significant differences were noted in chamber sizes or ejection fraction among the groups. Average serum cholesterol was higher in group 3 compared to groups 1 and 2 respectively (495 ± 305 mg/dl vs. 114 ± 95 mg/dl and 87 ± 37 mg/dl; p 2 = 0.17 p = 0.04, r2 = 0.37 p = 0.001 and r2 = 0.24 p = 0.01. Conclusion Cholesterol load in the serum and myocardium was significantly associated with decreased systolic and diastolic function by TDI. Moreover, lipid lowering was protective.

  9. Patterns of myocardial perfusion in humans evaluated with contrast-enhanced 320 multidetector computed tomography

    DEFF Research Database (Denmark)

    Kühl, J Tobias; Linde, Jesper J; Fuchs, Andreas

    2012-01-01

    of intravenous adenosine infusion on regional myocardial perfusion. To evaluate myocardial perfusion patterns at rest, we scanned 14 healthy subjects with PET and 14 age and gender matched subjects with 320 MDCT. To evaluate the effect of adenosine stress on relative perfusion patterns 14 subjects with near......-normal epicardial coronary arteries were studied at rest and during adenosine stress. Relative perfusion was assessed as attenuation density (AD) in 16 segments of the LV, and each segment was divided into 3 layers: endo-, mid- and epi-cardial. During rest the relative AD by MDCT was lower in the lateral wall...

  10. Extent of myocardial noncompaction: comparison between MRI and echocardiographic evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Alhabshan, Fahad; Smallhorn, Jeffrey F.; Golding, Fraser; Musewe, Norman; Freedom, Robert M. [University of Toronto, Department of Pediatrics, Division of Cardiology, Hospital for Sick Children, Toronto, Ontario (Canada); Yoo, Shi-Joon [University of Toronto, Department of Diagnostic Imaging, Division of Cardiology, Hospital for Sick Children, Toronto, Ontario (Canada)

    2005-11-01

    Noncompaction of the left ventricular myocardium is an important cause of cardiomyopathy. There is no clear consensus about its diagnostic criteria or the diagnostic test of choice. MRI is increasingly used in the pediatric cardiac field because of its superior and objective image quality. To compare the echocardiographic and MRI findings in four patients with recently diagnosed ventricular noncompaction. We compared the extent of myocardial involvement shown at MRI and echocardiography in four individuals, two patients with echocardiographic diagnosis of left ventricular noncompaction, and two family members of one of the patients. In all patients, MRI showed wider area of involvement than echocardiography. A definite diagnosis was entertained in only two patients by echocardiography but in all by MRI. Cine imaging was diagnostic of the disease in all patients. Black-blood pool imaging with double-inversion recovery sequence also helped to visualize the abnormal areas by showing slow flow artifacts in the four- and two-chamber images. MRI provided better delineation of the extent of the abnormal trabeculation in patients with noncompaction of the left ventricular myocardium. It was particularly useful when the myocardial involvement was subtle, as in the asymptomatic family members. (orig.)

  11. Effect of inversion time on the precision of myocardial late gadolinium enhancement quantification evaluated with synthetic inversion recovery MR imaging

    NARCIS (Netherlands)

    Varga-Szemes, Akos; van der Geest, Rob J; Schoepf, U Joseph; Spottiswoode, Bruce S; De Cecco, Carlo N; Muscogiuri, Giuseppe; Wichmann, Julian L; Mangold, Stefanie; Fuller, Stephen R; Maurovich-Horvat, Pal; Merkely, Bela; Litwin, Sheldon E; Vliegenthart, Rozemarijn; Suranyi, Pal

    OBJECTIVES: To evaluate the influence of inversion time (TI) on the precision of myocardial late gadolinium enhancement (LGE) quantification using synthetic inversion recovery (IR) imaging in patients with myocardial infarction (MI). METHODS: Fifty-three patients with suspected prior MI underwent

  12. Application of Anisotropy of Magnetic Susceptibility to large-scale fault kinematics: an evaluation

    Science.gov (United States)

    Casas, Antonio M.; Roman-Berdiel, Teresa; Marcén, Marcos; Oliva-Urcia, Belen; Soto, Ruth; Garcia-Lasanta, Cristina; Calvin, Pablo; Pocovi, Andres; Gil-Imaz, Andres; Pueyo-Anchuela, Oscar; Izquierdo-Llavall, Esther; Vernet, Eva; Santolaria, Pablo; Osacar, Cinta; Santanach, Pere; Corrado, Sveva; Invernizzi, Chiara; Aldega, Luca; Caricchi, Chiara; Villalain, Juan Jose

    2017-04-01

    Major discontinuities in the Earth's crust are expressed by faults that often cut across its whole thickness favoring, for example, the emplacement of magmas of mantelic origin. These long-lived faults are common in intra-plate environments and show multi-episodic activity that spans for hundred of million years and constitute first-order controls on plate evolution, favoring basin formation and inversion, rotations and the accommodation of deformation in large segments of plates. Since the post-Paleozoic evolution of these large-scale faults has taken place (and can only be observed) at shallow crustal levels, the accurate determination of fault kinematics is hampered by scarcely developed fault rocks, lack of classical structural indicators and the brittle deformation accompanying fault zones. These drawbacks are also found when thick clayey or evaporite levels, with or without diapiric movements, are the main detachment levels that facilitate large displacements in the upper crust. Anisotropy of Magnetic Susceptibility (AMS) provides a useful tool for the analysis of fault zones lacking fully developed kinematic indicators. However, its meaning in terms of deformational fabrics must be carefully checked by means of outcrop and thin section analysis in order to establish the relationship between the orientation of magnetic ellipsoid axes and the transport directions, as well as the representativity of scalar parameters regarding deformation mechanisms. Timing of faulting, P-T conditions and magnetic mineralogy are also major constraints for the interpretation of magnetic fabrics and therefore, separating ferro- and para-magnetic fabric components may be necessary in complex cases. AMS results indicate that the magnetic lineation can be parallel (when projected onto the shear plane) or perpendicular (i.e. parallel to the intersection lineation) to the transport direction depending mainly on the degree of shear deformation. Changes between the two end-members can

  13. Anisotropy in shrinkage during sintering

    Directory of Open Access Journals (Sweden)

    Zavaliangos A.

    2006-01-01

    Full Text Available While significant progress in modeling of sintering has been accomplished since the original paper by Frenkel "Viscous flow of crystalline bodies under action of surface tension", there are still several issues that remain open. One of them is anisotropy during sintering. In this paper we present some recent developments that improve our understanding of sintering anisotropy based on simulations of a two- dimensional array of particles. A number of possible sources of anisotropy are examined and evaluated. .

  14. Multidetector-row computed tomographic evaluation of myocardial perfusion in reperfused chronic myocardial infarction: value of color-coded perfusion map in a porcine model.

    Science.gov (United States)

    Yim, Nam Yeol; Kim, Yun-Hyeon; Choi, Song; Seon, Hyun Ju; Kim, Yeong Cheol; Jeong, Gwang Woo; Min, Byeong In; Lee, Sang Rok; Jeong, Myeong Ho; Kim, Jae Kyu; Park, Jin Gyoon; Kang, Heoung Keun

    2009-04-01

    We aimed to develop color-coded CT perfusion maps (CPM) of infarcted myocardium and assess the utility of CPM in evaluating ischemic heart disease on a cardiac multi-detector CT (MDCT) in a porcine reperfused-myocardial-infarction model. Myocardial infarctions were induced by 30 min occlusions of the proximal left anterior descending coronary artery (LAD) in 17 healthy adult female pigs. First-pass and 5 min-delayed cardiac MDCTs were performed after 4 weeks of LAD occlusion. Myocardial CPMs were obtained by using the CPM program. Triphenyltetrazolium chloride (TTC)-staining was performed on the cardiac specimens. We analyzed the intermodality agreement on the size and location of the myocardial infarctions. TTC staining revealed myocardial infarction in 16 of 17 pigs, and 15 of these (94%) showed matched infarcts on the CPM and first-pass images. The areas of perfusion deficit noted in early arterial phase images and CPM coincided exactly with the areas of poor TTC staining in 12 of 15 pigs (80%). In the three remaining pigs, the areas of poor TTC staining were larger than those of a perfusion deficit demonstrated by either early arterial phase images or CPM. The agreement between these tests is calculated to be moderate to good (k = 0.736, P infarction; CPM was helpful in visualizing the infarcted myocardium.

  15. Short- and long-term changes in myocardial function, morphology, edema, and infarct mass after ST-segment elevation myocardial infarction evaluated by serial magnetic resonance imaging

    DEFF Research Database (Denmark)

    Ripa, Rasmus Sejersten; Nilsson, Jens Christian; Wang, Yongzhong

    2007-01-01

    undertaken. The aim of this study was to evaluate effects of therapy for STEMI on left ventricular function and perfusion and to test the hypothesis that myocardial perfusion by MRI predicts recovery of left ventricular function. METHODS: Cine MRI, edema, first-pass perfusion, and late enhancement imaging...

  16. Quantitative evaluation of thallium-201 myocardial scintigram in coronary artery diseases

    Energy Technology Data Exchange (ETDEWEB)

    Mikada, Ken-etsu (Akita Univ. (Japan). School of Medicine)

    1992-11-01

    Quantitative indices from circumferential profile curves of thallium-201 ([sup 201]Tl) myocardial scintigram were evaluated for diagnostic utility in coronary artery diseases (CAD). Myocardial [sup 201]Tl scintigrams with single photon emission computed tomography (SPECT) were obtained 5 minutes (early) and 4 hours (delayed) after exercise in 20 normal subjects and 66 cases of CAD, of which 20 were angina pectoris without myocardial infarction (AP), 14 were subendocardial infarction (non-QMI) and 32 were Q-wave infarction (QMI). Tl counts, %Tl uptake and washout ratio (WR) were measured in 81 segments (9 apical segments of the slice from the longitudinal axis and all 72 segments of two slices from the short axis). A mean early defect (MED), a mean delayed defect (MDD), a mean delta washout rate (MDR), and a [Sigma] delayed defect ([Sigma]DD) were calculated from the areas which were below the two standard deviations of the mean %Tl uptake in normal subjects. A mean filling-in (MFI) was calculated from the difference of the %Tl uptake between early and delayed curves in each patient. In patients with CAD, the MED and MFI were higher, but MDW was lower with a more severe coronary stenosis, indicating that these indices were useful to detect myocardial hypo-perfuion. In severely stenotic regions, the MDD was higher in QMI than in AP and non-QMI, indicating that the ratio of infarct to the myocardium in the region was higher in QMI. In QMI, [Sigma]DD correlated well (r=0.723) with Total Wall Motion Scores with two-dimentional echocardiography which was directly related with infarct size. Further, MED, MFI and MDW were improved after aortocoronary bypass only in patients with patent graft. It is concluded that this quantitative evaluation with [sup 201]Tl-SPECT can provide an objective and quantitative estimate of regional myocardial ischemia and infarct. (author).

  17. Visual evaluation of I-123-betamethyliodophenylpentadecanoic acid (BMIPP) myocardial SPECT findings in hypertrophic cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Bunko, Hisashi; Tonami, Norihisa; Hisada, Kinichi (Kanazawa Univ. (Japan). School of Medicine)

    1993-03-01

    I-123-betamethyliodophenylpentadecanoic acid (BMIPP) is a branched fatty acid analogue for the imaging of myocardial metabolism. Seventeen patients with hypertrophic cardiomyopathy (HCM) and 17 patients with ischemic or valvular heart diseases (non-HCMs) were studied to evaluate the characteristic findings of the BMIPP myocardial images in HCM. Early (20 min) and delayed (3 hr) images were obtained after intravenous injection of 111 MBq of BMIPP with 3-headed SPECT. Tl-201 myocardial SPECT was also obtained within a week of BMIPP SPECT. Regional myocardial uptake of BMIPP relative to Tl-201 and its serial change from early to delayed images were visually evaluated in patient basis as well as segmental basis. Decreased uptake of BMIPP in HCM was frequently seen in anterior, septal, apical and inferior wall. Relatively decreased myocardial uptake of BMIPP (type H+B) was seen in 14 patients (82%) of HCM which was significantly higher than non-HCMs (12%, p<0.001). Number of segments with type H+B was higher in HCM than non-HCMs (mean: 4.59 vs 0.53, p<0.001). This relative decrease of BMIPP uptake was frequently seen in hypertrophied segments of HCM (71%, p<0.01). Serial decrease of regional BMIPP uptake was also frequently seen in HCM especially in hypertrophied myocardium than non-HCMs (76% vs 41%, p<0.01). This was concordant with segmental analysis (mean: 3.41 vs 1.06, p<0.01). Significant decrease in BMIPP image quality in HCM was concordant with higher frequency of serial decrease of BMIPP in HCM. In conclusion, HCM patients frequently showed abnormality of BMIPP uptake and retention which indicated the presence of metabolic abnormality in hypertrophied myocardium. (author).

  18. Evaluation of myocardial CT perfusion in patients presenting with acute chest pain to the emergency department: comparison with SPECT-myocardial perfusion imaging.

    Science.gov (United States)

    Feuchtner, Gudrun Maria; Plank, Fabian; Pena, Constantino; Battle, Juan; Min, James; Leipsic, Jonathon; Labounty, Troy; Janowitz, Warren; Katzen, Barry; Ziffer, Jack; Cury, Ricardo C

    2012-10-01

    To determine whether evaluation of resting myocardial CT perfusion (CTP) from coronary CT angiography (CTA) datasets in patients presenting with chest pain (CP) to the emergency department (ED), might have added value to coronary CTA. 76 Patients (age 54.9 y±13; 32 (42%) women) presenting with CP to the ED underwent coronary 64-slice CTA. Myocardial perfusion defects were evaluated for CTP (American Heart Association 17-segment model) and compared with rest sestamibi single-photon emission CT myocardial perfusion imaging (SPECT-MPI). CTA was assessed for >50% stenosis per vessel. CTP demonstrated a sensitivity of 92% and 89%, specificity of 95% and 99%, positive predictive value (PPV) of 80% and 82% and negative predictive value (NPV) of 98% and 99% for each patient and for each segment, respectively. CTA showed an accuracy of 92%, sensitivity of 70.4%, specificity of 95.5%, PPV 67.8%, and NPV of 95% compared with SPECT-MPI. When CTP findings were added to CTA the PPV improved from 67% to 90.1%. In patients presenting to the ED with CP, the evaluation of rest myocardial CTP demonstrates high diagnostic performance as compared with SPECT-MPI. Addition of CTP to CTA improves the accuracy of CTA, primarily by reducing rates of false-positive CTA.

  19. Angioscopic Evaluation of Thrombi in the Culprit Coronary Lesions in Patients With Acute Myocardial Infarction

    OpenAIRE

    Morio, H.; Fujimori, Y.; Terasawa, K; Hasegawa, O.; Matsuo, A.; Osegawa, M.

    2000-01-01

    The purpose of this study was to evaluate intracoronary thrombi in the culprit lesions in patients with acute myocardial infarction (AMI) by angioscopy, and to compare them with clinical and angiographic features. We angioscopically observed the culprit coronary lesions in 66 patients with AMI (55 males and 11 females, 63.9±15.4 years old) just before interventional therapy. Thrombi were observed in 42 of 66 lesions (64%), namely, red thrombi in 16, mixed thrombi in 15, ...

  20. Regional left ventricular myocardial contraction abnormalities and asynchrony in patients with hypertrophic cardiomyopathy evaluated by magnetic resonance spatial modulation of magnetization myocardial tagging

    Energy Technology Data Exchange (ETDEWEB)

    Mishiro, Yuichiro; Oki, Takashi [Tokushima Univ. (Japan). School of Medicine; Iuchi, Arata [and others

    1999-06-01

    Global left ventricular (LV) pump function is generally preserved in patients with hypertrophic cardiomyopathy (HCM). However, it is unknown whether regional myocardial contractility is impaired, especially in nonhypertrophied regions. The purpose of this study was to evaluate regional LV myocardial contraction in patients with HCM using magnetic resonance (MR) spatial modulation of magnetization (SPAMM) myocardial tagging. The study group comprised 20 patients with asymmetric septal hypertrophy (HCM group) and 16 age-matched normal patients (control group), and data were collected using transthoracic M-mode and 2-dimensional echocardiography, and MR SPAMM myocardial tagging. The systolic strain ratio, maximum systolic strain velocity, and time from end-diastole to maximum systolic strain ({Delta}T) in the anterior, ventricular septal, inferior and lateral regions for 2 LV short-axis sections at the levels of the chordae tendineae and papillary muscles were measured at 50-ms intervals by MR myocardial tagging. The end-diastolic anterior and ventricular septal wall thicknesses and LV mass index were significantly different between the HCM and control groups. The systolic strain ratio for all 4 walls, particularly the anterior and ventricular septal regions, was significantly lower in the HCM group. In the HCM group, the maximum systolic strain velocity was significantly lower and {Delta}T was significantly shorter for all 4 walls, particularly the anterior and ventricular septal regions. The standard deviation for the {Delta}T, calculated from the {Delta}T for the 8 regions of the 2 LV short-axis sections, was significantly greater in the HCM group. In conclusion, regional LV myocardial contraction is impaired in both hypertrophied and nonhypertrophied regions, and systolic LV wall asynchrony occurs in patients with HCM. (author)

  1. Evaluation of myocardial damage and cardiac residual capacity by Tl-201 myocardial scintigraphy in valvular heart diseases

    Energy Technology Data Exchange (ETDEWEB)

    Indo, Shunju (Okayama Univ. (Japan). School of Medicine)

    1992-12-01

    This study was performed to clarify whether the extent-score (Ex-Score) calculated by Tl-201 myocardial scintigraphy is a reliable indicator of the severity of myocardial damage and cardiac residual capacity in valvular heart diseases. The subjects consisted of 38 patients (10 with aortic regurgitation (AR), 4 with aortic stenosis (AS), 13 with mitral regurgitation (MR) and 11 with mitral stenosis (MS)). Ex-Scores were significantly correlated with the severity of myocardial damage found in biopsied specimens obtained intraoperatively (correlation efficiency to Ex-Score with cell diameter in AR, % fibrosis in AR, cell diameter in AS, electron microscopic score in MR and % fibrosis in MS was 0.873, 0.734, 0.970, 0.913 and 0.659, respectively). Ex-Scores were also correlated with cardiac residual capacity determined by radioisotope angiography (correlation efficiency to Ex-Score with %[Delta] ejection fraction in AR, %[Delta] end-systolic volume in MR, %[Delta] end-diastolic volume in MS was -0.764, 0.790 and -0.763, respectively). These results suggest that the severity of myocardial damage and cardiac residual capacity can be estimated by Tl-201 myocardial scintigraphy (Ex-Score) in valvular heart diseases. (author).

  2. Myocardial Revascularization in Dyalitic Patients: In-Hospital Period Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Matheus, E-mail: matheus10miranda@gmail.com; Hossne, Nelson Américo Jr.; Branco, João Nelson Rodrigues; Vargas, Guilherme Flora; Fonseca, José Honório de Almeida Palma da; Pestana, José Osmar Medina de Abreu [Escola Paulista de Medicina (EPM), Universidade Federal de São Paulo (Unifesp), São Paulo, SP (Brazil); Juliano, Yara [Universidade de Santo Amaro, São Paulo, SP (Brazil); Buffolo, Enio [Escola Paulista de Medicina (EPM), Universidade Federal de São Paulo (Unifesp), São Paulo, SP (Brazil)

    2014-02-15

    Coronary artery bypass grafting currently is the best treatment for dialytic patients with multivessel coronary disease, but hospital morbidity and mortality related to procedure is still high. Evaluate results and in-hospital outcomes of coronary artery bypass grafting in dialytic patients. Retrospective unicentric study including 50 consecutive and not selected dialytic patients, who underwent coronary artery bypass grafting in a tertiary university hospital from 2007 to 2012. High prevalence of cardiovascular risk factors was observed (100% hypertensive, 68% diabetic and 40% dyslipidemic). There was no intra-operative death and 60% of the procedures were performed off-pump. There were seven (14%) in-hospital deaths. Postoperative infection, previous heart failure, cardiopulmonary bypass, abnormal ventricular function and surgical re-exploration were associated with increased mortality. Coronary artery bypass grafting is feasible to dialytic patients although high in-hospital morbidity and mortality. It is necessary better understanding about metabolic aspects to plan adequate interventions.

  3. Frequency of myocardial injury after blunt chest trauma as evaluated by radionuclide angiography

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, G.R.; Driedger, A.A.; Holliday, R.L.; Cheung, H.W.; Sibbald, W.J.

    1983-11-01

    Seventy-seven patients who had sustained multisystem trauma, including severe blunt chest injury, were prospectively evaluated to assess the frequency of associated traumatic myocardial injury. Traumatic injury to either the right or left ventricle was defined by the presence of discrete abnormalities of wall motion on electrocardiographically gated cardiac scintigraphy in patients without a clinical history of heart disease. Forty-two patients (55%) (Group 1) had focal abnormalities of wall motion; 27 involved the right ventricle, 7 the left ventricle, 7 were biventricular, and 1 involved only the septum. Both the right and left ventricular ejection fractions were significantly lower (31 +/- 11% and 47 +/- 14%, respectively) than those in the 35 traumatized patients without wall motion abnormalities on scintigraphy (Group 2) (49 +/- 8% and 58 +/- 11%, respectively). Repeat scintigraphic examination in 32 Group 1 patients at a time remote from initial injury showed improvement or resolution of previously defined focal wall motion abnormalities in 27 of 32 patients (84%). The electrocardiogram and serum enzyme tests were insensitive indexes of traumatic myocardial injury when defined by the scintigraphic abnormalities. Thus, severe blunt chest trauma results in a higher frequency of traumatic myocardial injury than heretofore recognized, and frequently involves the anteriorly situated right ventricle.

  4. Quantitative three-dimensional evaluation of myocardial perfusion during regadenoson stress using multidetector computed tomography.

    Science.gov (United States)

    Mor-Avi, Victor; Lodato, Joseph A; Kachenoura, Nadjia; Chandra, Sonal; Freed, Benjamin H; Newby, Barbara; Lang, Roberto M; Patel, Amit R

    2012-01-01

    The ability of multidetector computed tomography (MDCT) to detect stress-induced myocardial perfusion abnormalities is of great clinical interest as a potential tool for the combined evaluation of coronary stenosis and its hemodynamic significance. We tested the hypothesis that quantitative 3-dimensional (3D) analysis of myocardial perfusion from MDCT images obtained during regadenoson stress would more accurately detect the presence of significant coronary artery disease (CAD) than identical analysis when performed on resting MDCT images. We prospectively studied 50 consecutive patients referred for CT coronary angiography (CTCA) who agreed to undergo additional imaging with regadenoson (0.4 mg; Astellas). Images were acquired using prospective gating (256-channel; Philips). Custom analysis software was used to define 3D myocardial segments, and calculate for each segment an index of severity and extent of perfusion abnormality, Qh, which was compared with perfusion defects predicted by the presence and severity of coronary stenosis on CTCA. Three patients were excluded because of image artifacts. In the remaining 47 patients, CTCA depicted stenosis more than 50% in 23 patients in 37 of 141 coronary arteries. In segments supplied by the obstructed arteries, myocardial attenuation was slightly reduced compared with normally perfused segments at rest (mean [SD], 91 [21] vs 93 [26] Hounsfield units, not significant) and, to a larger extent, at peak stress (102 [21] vs 112 [20] Hounsfield units, P regadenoson improved the diagnosis of CAD, as reflected by an increase in sensitivity (from 0.57 to 0.91) and improvement in accuracy (from 0.65 to 0.77). Quantitative 3D analysis of MDCT images allows objective detection of CAD, the accuracy of which is improved by regadenoson stress.

  5. Angiotensin-converting enzyme inhibition after myocardial infarction: the Trandolapril Cardiac Evaluation Study

    DEFF Research Database (Denmark)

    Torp-Pedersen, C; Køber, L; Carlsen, J

    1996-01-01

    To study the importance of giving an angiotensin-converting enzyme (ACE) inhibitor to patients with reduced systolic function after an infarction, the Trandodolapril Cardiac Evaluation study was designed to include the majority of patients with echocardiographic signs of left ventricular...... for discontinuation for 48 and 75 patients in the trandolapril and placebo groups, respectively. In conclusion, long-term treatment with trandolapril in patients with reduced left ventricular function shortly after myocardial infarction significantly reduced mortality and morbidity. Most patients received the target...

  6. Evaluation of post-contrast myocardial t1 in duchenne muscular dystrophy using cardiac magnetic resonance imaging.

    Science.gov (United States)

    Soslow, Jonathan H; Damon, Bruce M; Saville, Benjamin R; Lu, Zengqi; Burnette, W Bryan; Lawson, Mark A; Parra, David A; Sawyer, Douglas B; Markham, Larry W

    2015-01-01

    The objective of the study was to perform a retrospective pilot study to evaluate the potential of myocardial T1 in assessment of Duchenne muscular dystrophy (DMD) cardiomyopathy. Early identification of DMD cardiac disease, particularly myocardial fibrosis, would allow earlier therapy, potentially improving outcomes. Shortened myocardial T1 measured by cardiac MRI (CMR) is a measure of cardiac fibrosis that may be detected before late gadolinium enhancement (LGE). We hypothesized that the post-contrast T1 obtained from the Look-Locker sequences (T1LL), an easily obtainable surrogate of myocardial T1, would be abnormally shortened in DMD compared with controls. T1LL measurement was performed on 21 DMD subjects and 11 controls; to account for individual variations in gadolinium distribution, myocardial T1LL was divided by blood pool T1LL, deriving T1LL ratios. DMD subjects had shorter mean T1LL ratio than controls (1.42 vs 1.72, p DMD subjects with normal LVEF and without LGE also demonstrated significantly shorter T1LL ratio (-0.28, p contrast T1LL ratio is abnormally shortened in DMD compared with controls, even in DMD patients with otherwise normal CMRs. The application of more aggressive therapy for those with shorter T1LL may favorably alter morbidity and improve mortality associated with DMD cardiomyopathy. These data suggest that further prospective evaluation of myocardial T1 will be of benefit to patients with DMD.

  7. A Novel Prehospital Electrocardiogram Score Predicts Myocardial Salvage in Patients with ST-Segment Elevation Myocardial Infarction Evaluated by Cardiac Magnetic Resonance

    DEFF Research Database (Denmark)

    Schoos, Mikkel Malby; Lønborg, Jacob; Vejlstrup, Niels

    2013-01-01

    We hypothesized that prehopsital ECG scores can identify ST-segment elevation myocardial infarction (STEMI) patients in whom time delay is particularly important for myocardial salvage.......We hypothesized that prehopsital ECG scores can identify ST-segment elevation myocardial infarction (STEMI) patients in whom time delay is particularly important for myocardial salvage....

  8. Evaluation of Soft Tissue Sarcoma Tumors Electrical Conductivity Anisotropy Using Diffusion Tensor Imaging for Numerical Modeling on Electroporation

    Directory of Open Access Journals (Sweden)

    Ghazikhanlou-sani K.

    2016-06-01

    Full Text Available Introduction: There is many ways to assessing the electrical conductivity anisotropy of a tumor. Applying the values of tissue electrical conductivity anisotropy is crucial in numerical modeling of the electric and thermal field distribution in electroporation treatments. This study aims to calculate the tissues electrical conductivity anisotropy in patients with sarcoma tumors using diffusion tensor imaging technique. Materials and Method: A total of 3 subjects were involved in this study. All of patients had clinically apparent sarcoma tumors at the extremities. The T1, T2 and DTI images were performed using a 3-Tesla multi-coil, multi-channel MRI system. The fractional anisotropy (FA maps were performed using the FSL (FMRI software library software regarding the DTI images. The 3D matrix of the FA maps of each area (tumor, normal soft tissue and bone/s was reconstructed and the anisotropy matrix was calculated regarding to the FA values. Result: The mean FA values in direction of main axis in sarcoma tumors were ranged between 0.475–0.690. With assumption of isotropy of the electrical conductivity, the FA value of electrical conductivity at each X, Y and Z coordinate axes would be equal to 0.577. The gathered results showed that there is a mean error band of 20% in electrical conductivity, if the electrical conductivity anisotropy not concluded at the calculations. The comparison of FA values showed that there is a significant statistical difference between the mean FA value of tumor and normal soft tissues (P<0.05. Conclusion: DTI is a feasible technique for the assessment of electrical conductivity anisotropy of tissues. It is crucial to quantify the electrical conductivity anisotropy data of tissues for numerical modeling of electroporation treatments.

  9. Myocardial Bridge

    Science.gov (United States)

    ... Sudden Cardiac Arrest Valve Disease Vulnerable Plaque Myocardial Bridge Related terms: myocardium, coronary arteries, myocardial ischemia Your ... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart ...

  10. Detection of unsuspected myocardial ishemia during F-18 FDG PET in the evaluation of a solitary pulmonary nodule

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan H.; Park, Kwang J.; Lee, Myoung Hoon [College of Medicine, Ajou Univ., Suwon (Korea, Republic of)

    2001-07-01

    Enhanced F-18 FDG uptake at rest after an overnight fast occurs in myocardial ischemia and is associated with functional improvement after PTCA or CABG. For more pronounced regional differences of FDG uptake in the fasting state occur, the detection of dysfunctional myocardium during oncologic application of FDG PET has not been productive. A case of unsuspected myocardial ischemia indicated by focal FDG uptake during camera based (CB) FDG PET in the evaluation of a solitary pulmonary nodule is described. A 58-year-old male patient was admitted to the hospital for the evaluation of a solitary pulmonary nodule (SPN) measuring 1.7 cm in diameter in the right upper lobe. CB FDG PET for diagnosis of lung cancer and staging depicted lung cancer without nodal involvement but there was increased FDG uptake in the region of inferior wall of LV. CB FDG PET without attenuation correction always depicts decreased FDG uptake in the inferior wall when LV is visualized. Therefore, only FDG uptake in inferior wall in this case was indicative of myocardial ischemia and next day stress Tl-201 myocardial SPECT was performed. This demonstrated inferior wall ischemia which was confirmed by coronary angiogram. Then he underwent PTCA for 80% stenosis of mid RCA and right ventricular branch followed by right upper lobectomy one month after the PTCA. In conclusion, a rare finding of enhanced myocardial uptake of F-18 FDG at rest during CD FDG PET for SPN was associated with myocardial ischemia. Clinically unsuspected myocardial ischemia was treated successfully by PTCA before lobectomy for NSCLC for the patient.

  11. In vitro biological and mechanical evaluation of various scaffold materials for myocardial tissue engineering.

    Science.gov (United States)

    Herrmann, Florian E M; Lehner, Anja; Hollweck, Trixi; Haas, Ulrike; Fano, Cornelia; Fehrenbach, David; Kozlik-Feldmann, Rainer; Wintermantel, Erich; Eissner, Gunther; Hagl, Christian; Akra, Bassil

    2014-04-01

    A cardiac patch is a construct devised in regenerative medicine to replace necrotic heart tissue after myocardial infarctions. The cardiac patch consists of a scaffold seeded with stem cells. To identify the best scaffold for cardiac patch construction we compared polyurethane, Collagen Cell Carriers, ePTFE, and ePTFE SSP1-RGD regarding their receptiveness to seeding with mesenchymal stem cells isolated from umbilical cord tissue. Seeding was tested at an array of cell seeding densities. The bioartificial patches were cultured for up to 35 days and evaluated by scanning electron microscopy, microscopy of histological stains, fluorescence microscopy, and mitochondrial assays. Polyurethane was the only biomaterial which resulted in an organized multilayer (seeding density: 0.750 × 10(6) cells/cm(2)). Cultured over 35 days at this seeding density the mitochondrial activity of the cells on polyurethane patches continually increased. There was no decrease in the E Modulus of polyurethane once seeded with cells. Seeding of CCC could only be realized at a low seeding density and both ePTFE and ePTFE SSP1-RGD were found to be unreceptive to seeding. Of the tested scaffolds polyurethane thus crystallized as the most appropriate for seeding with mesenchymal stem cells in the framework of myocardial tissue engineering. Copyright © 2013 Wiley Periodicals, Inc.

  12. Quantitative evaluation of ischemic myocardial scar tissue by unenhanced T1 mapping using 3.0 Tesla MR scanner.

    Science.gov (United States)

    Okur, Aylin; Kantarcı, Mecit; Kızrak, Yeşim; Yıldız, Sema; Pirimoğlu, Berhan; Karaca, Leyla; Oğul, Hayri; Sevimli, Serdar

    2014-01-01

    We aimed to use a noninvasive method for quantifying T1 values of chronic myocardial infarction scar by cardiac magnetic resonance imaging (MRI), and determine its diagnostic performance. We performed cardiac MRI on 29 consecutive patients with known coronary artery disease (CAD) on 3.0 Tesla MRI scanner. An unenhanced T1 mapping technique was used to calculate T1 relaxation time of myocardial scar tissue, and its diagnostic performance was evaluated. Chronic scar tissue was identified by delayed contrast-enhancement (DE) MRI and T2-weighted images. Sensitivity, specificity, and accuracy values were calculated for T1 mapping using DE images as the gold standard. Four hundred and forty-two segments were analyzed in 26 patients. While myocardial chronic scar was demonstrated in 45 segments on DE images, T1 mapping MRI showed a chronic scar area in 54 segments. T1 relaxation time was higher in chronic scar tissue, compared with remote areas (1314±98 ms vs. 1099±90 ms, P T1 values were shown in areas of myocardium colocalized with areas of DE and normal signal on T2-weighted images. There was a significant correlation between T1 mapping and DE images in evaluation of myocardial wall injury extent (P T1 mapping MRI combined with T2-weighted images might be a feasible imaging modality for detecting chronic myocardial infarction scar tissue.

  13. [Establishment of myocardial targeted nanoparticles and preliminary evaluation of its effects on prevention and treatment of myocardial injury].

    Science.gov (United States)

    Liu, Y Y; Wang, C; Luo, P F; Xia, Z F

    2017-11-20

    Objective: To establish 3-{4-[2-hydroxyl-(1-methylethylamino) propoxy] phenyl} propionic acid cetylesters (PAC) modified nanoparticles, and preliminarily explore its cardiomyocyte-targeting function and protection effects on myocardium. Methods: (1) HL-1 myocardial cells were divided into cyanidin-3 (Cy3) marked non-targeted small interference RNA (Cy3-siNC) group and Cy3 marked small interference RNA designed for the nuclear factor kappa B (NF-κB)-p65 gene (Cy3-si435) group according to the random number table, with 3 wells in each group. Cells in Cy3-siNC group were transfected with Cy3-siNC, while cells in Cy3-si435 group were transfected with Cy3-si435. At transfection hour 24, the mRNA expression of NF-κB-p65 of cells was determined by real-time fluorescent quantitative polymerase chain reaction. (2) Multiple emulsificating solvent evaporating method was adopted to prepare PAC modified nanoparticles carried with Cy3-siNC (Cy3-siNC-PAC) and PAC modified nanoparticles carried with Cy3-si435 (Cy3-si435-PAC). The morphology of Cy3-si435-PAC nanoparticles was observed with scanning electron microscope, and the size and potential of Cy3-si435-PAC nanoparticles were detected by nanometer particle size and zeta potential analyzer. The entrapment efficiency and drug loadings of Cy3-si435-PAC nanoparticle were determined with ultraviolet spectrophotometer. The release of Cy3-si435 of Cy3-si435-PAC nanoparticles was determined by dialysis method. (3) Another batch of HL-1 cells were divided into 4 groups according to the random number table, with 9 wells in each group. Cells in negative control group were added with 5 μL phosphate buffer. Cells in 25, 50, and 100 mg/mL Cy3-si435-PAC nanoparticles groups were added with 5 μL 25, 50, and 100 mg/mL Cy3-si435-PAC nanoparticles, respectively. At transfection hour 6, 12, and 24, proliferation activity of cells in 3 wells of each group was detected by methyl thiazolyl tetrazolium method, respectively. (4) Another batch of

  14. Non-invasive evaluation of myocardial reperfusion by transthoracic Doppler echocardiography and single-photon emission computed tomography in patients with anterior acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    Celutkiene Jelena

    2011-05-01

    Full Text Available Abstract Background The study was designed to evaluate whether the preserved coronary flow reserve (CFR 72 hours after reperfused acute myocardial infarction (AMI is associated with less microvascular dysfunction and is predictive of left ventricular (LV functional recovery and the final infarct size at follow-up. Methods In our study, CFR was assessed by transthoracic Doppler echocardiography (TDE in 44 patients after the successful percutaneous coronary intervention during the acute AMI phase. CFR was correlated with contractile reserve assessed by low-dose dobutamine echocardiography and with the total perfusion defect measured by single-photon emission computed tomography 72 hours after reperfusion and at 5 months follow-up. The ROC analysis was performed to determine test sensitivity and specificity based on CFR. Categorical data were compared by an χ2 analysis, continuous variables were analysed with the independent Student's t test. In order to analyse correlation between CFR and the parameters of LV function and perfusion, the Pearson correlation analysis was conducted. The linear regression analysis was used to assess the relationship between CFR and myocardial contractility as well as the final infarct size. Results We estimated the CFR cut-off value of 1.75 as providing the maximal accuracy to distinguish between patients with preserved and impaired CFR during the acute AMI phase (sensitivity 91.7%, specificity 75%. Wall motion score index was better in the subgroup with preserved CFR as compared to the subgroup with reduced CFR: 1.74 (0.29 vs. 1.89 (0.17 (p Conclusion The early measurement of CFR by TDE can be of high value for the assessment of successful reperfusion in AMI and can be used to predict LV functional recovery, myocardial viability and the final infarct size.

  15. Prognostic risk stratification of myocardial ischaemia evaluated by gated myocardial perfusion SPECT in patients with chronic kidney disease

    Energy Technology Data Exchange (ETDEWEB)

    Hatta, Tsuguru [Ohmihachiman Community Medical Center, Division of Nephrology, Department of Medicine, Shiga (Japan); Nishimura, Shigeyuki [Saitama Medical School Hospital, Division of Cardiology, Saitama (Japan); Nishimura, Tsunehiko [Kyoto Prefectural University of Medicine, Department of Radiology, Graduate School of Medical Science, Kyoto (Japan)

    2009-11-15

    The aim of this study was to identify useful predictors of cardiac events in patients with chronic kidney disease (CKD). Among 4,031 patients identified from the Japanese Assessment of Cardiac Events and Survival Study (J-ACCESS) database with suspected or known ischaemic heart disease, we selected 820 with an estimated glomerular filtration rate (eGFR) of < 60 ml/min per 1.73 m{sup 2}. A total of 75 cardiac events developed among these 820 patients. The incidence of cardiac events was higher in the group with a lower eGFR. Multivariate Cox analysis indicated that age, diabetes mellitus, end-systolic volume, summed stress score (SSS) and eGFR were predictors of cardiac events. Event rates of patients with SSS {>=} 9 were significantly higher in groups with lower eGFR values (< 40 and 40-49 ml/min). The SSS value ({>=} 9) is a reliable predictor of cardiac events and myocardial single photon emission computed tomography has incremental value for predicting cardiac events and survival in CKD. (orig.)

  16. Transient myocardial ischemia after myocardial infarction

    DEFF Research Database (Denmark)

    Mickley, H

    1995-01-01

    Ambulatory ST-segment monitoring is a relatively new device in the evaluation of myocardial ischemia. The method is unique in allowing us to continuously examine the patient over an extended period of time in a changing environmental milieu. In survivors of acute myocardial infarction the prevale...

  17. Evaluation of right atrial function by two-dimensional speckle-tracking echocardiography in patients with right ventricular myocardial infarction.

    Science.gov (United States)

    Nourian, Saeed; Hosseinsabet, Ali; Jalali, Arash; Mohseni-Badalabadi, Reza

    2017-01-01

    Right ventricular myocardial infarction (RVMI) damages the systolic and diastolic functions of the RV, so the right atrium interacts with the RV with an acutely altered function. The aim of our study was to compare right atrial function as evaluated by 2D speckle-tracking echocardiography (2DSTE) between patients with inferior wall myocardial infarction (INFMI) and patients affected by both inferior myocardial infarction and right ventricular myocardial infarction (INFMI + RVMI). Our study recruited 70 consecutive patients with INFMI (43 patients without RVMI and 27 patients with RVMI). Right atrial function was evaluated by 2DSTE. Early diastolic strain, systolic strain rate, absolute value of early diastolic strain rate, expansion index, and diastolic emptying index of the right atrium were reduced in the patients with INFMI + RVMI compared to the patients with INFMI. The area under the curve for early diastolic strain for INFMI diagnosis was 0.682 (p value = 0.011, 95 % CI 0.550-0.815). Right atrial early diastolic longitudinal strain right atrial reservoir and conduit functions were impaired in the patients with INFMI + RVMI compared with the patients with INFMI.

  18. Comparative evaluation of HMG CoA reductase inhibitors in experimentally-induced myocardial necrosis: Biochemical, morphological and histological studies.

    Science.gov (United States)

    Variya, Bhavesh C; Patel, Snehal S; Trivedi, Jinal I; Gandhi, Hardik P; Rathod, S P

    2015-10-05

    The present study was carried out to evaluate the protective effect of different statins on isoproterenol (ISO) induced myocardial necrosis. Atorvastatin, rosuvastatin, fluvastatin, simvastatin and pravastatin (10 mg/kg/day) were administered for 12 weeks. After pretreatment of 12 weeks myocardial necrosis was induced by subsequent injection of ISO (85 mg/kg/day, s.c.) to wistar rats. Serum biochemical parameters like glucose, lipid profile, cardiac markers and transaminases were evaluated. Animals were killed and heart was excised for histopathology and antioxidant study. Statins pretreated rats showed significant protection against ISO induced elevation in serum biochemical parameters and serum level of cardiac marker enzymes and transaminase level as compared to ISO control group. Mild to moderate protection was observed in different statins treated heart in histopathology and TTC stained sections. Result from our study also revealed that statins could efficiently protect against ISO intoxicated myocardial necrosis by impairing membrane bound enzyme integrity and endogenous antioxidant enzyme levels. Amongst all statins used, rosuvastatin and pravastatin were found to have maximum cardio-protective activity against ISO induced myocardial necrosis as compared to other statins. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Elastic anisotropy of crystals

    Directory of Open Access Journals (Sweden)

    Christopher M. Kube

    2016-09-01

    Full Text Available An anisotropy index seeks to quantify how directionally dependent the properties of a system are. In this article, the focus is on quantifying the elastic anisotropy of crystalline materials. Previous elastic anisotropy indices are reviewed and their shortcomings discussed. A new scalar log-Euclidean anisotropy measure AL is proposed, which overcomes these deficiencies. It is based on a distance measure in a log-Euclidean space applied to fourth-rank elastic tensors. AL is an absolute measure of anisotropy where the limiting case of perfect isotropy yields zero. It is a universal measure of anisotropy applicable to all crystalline materials. Specific examples of strong anisotropy are highlighted. A supplementary material provides an anisotropy table giving the values of AL for 2,176 crystallite compounds.

  20. Clinical application of fetal left modified myocardial performance index in the evaluation of fetal growth restriction.

    Science.gov (United States)

    Nassr, Ahmed Abobakr; Youssef, Alaaeldin Abdelhamid; Zakherah, Mahmoud Sayed; Ismail, Alaa Mahmoud; Brost, Brian Charles

    2015-11-01

    This study aims to evaluate cardiac function in fetuses with intrauterine growth restriction (IUGR) compared with healthy fetuses, using the left modified myocardial performance index (MPI) and the association between MPI and perinatal outcome. Pregnant women between 34 and 39 weeks of gestation, who met the criteria for IUGR and were scheduled for delivery at an Egyptian tertiary medical center, were prospectively enrolled in the study. Women in the same gestational-age group with uncomplicated pregnancies were included as a control group. MPI was measured in all fetuses. The IUGR group was analyzed based on normal and abnormal umbilical artery (UA) Doppler. Perinatal outcomes were recorded. The mean left MPI was significantly higher in IUGR fetuses with abnormal UA Doppler (mean 0.58±SD 0.093) compared with healthy fetuses (mean 0.45±SD 0.070) (PIUGR fetuses with abnormal left MPI showed significantly worse perinatal outcome and increased morbidity compared with the control group. IUGR fetuses with abnormal left MPI also showed significantly worse perinatal outcome compared with IUGR fetuses with normal MPI (whether the UA Doppler was normal or abnormal). The fetal MPI was associated with the severity of fetal compromise in IUGR fetuses based on the perinatal outcome. MPI is a potentially useful tool in evaluating fetuses with suspected IUGR, which is crucial in classifying IUGR pregnancies into critical and non-critical cases and in predicting neonatal outcome.

  1. Myocardial response to a triathlon in male athletes evaluated by Doppler tissue imaging and biochemical parameters

    DEFF Research Database (Denmark)

    Leetmaa, T H; Dam, A; Glintborg, D

    2008-01-01

    The aim of this study was to examine cardiac dysfunction following ultra-endurance exercise in male athletes. Fourteen athletes (mean+/-SD, age 39+/-8 years) were evaluated before and after the European Championship in Triathlon 2003 using echocardiogram (ECG), cardiac markers [cardiac troponin T...... and systolic velocities decreased, thus suggesting reversible cardiac fatigue. When using cardiac markers and echocardiographic findings, a triathlon was found to have no significant negative effects on left ventricular function or myocardial tissue in male athletes.......The aim of this study was to examine cardiac dysfunction following ultra-endurance exercise in male athletes. Fourteen athletes (mean+/-SD, age 39+/-8 years) were evaluated before and after the European Championship in Triathlon 2003 using echocardiogram (ECG), cardiac markers [cardiac troponin T...... echocardiography, no significant differences were found in regional or global systolic parameters. Early diastolic peak flow velocity (9+/-2, P = 0.04) and E/A ratio (2+/-1, P = 0.004) were increased pre-race and decreased significantly toward normal values. In one athlete, cTnT levels increased significantly...

  2. Myocardial Scintigraphy in the Evaluation of Cardiac Events in Patients without Typical Symptoms

    Energy Technology Data Exchange (ETDEWEB)

    Smanio, Paola Emanuela Poggio, E-mail: pgmsmanio@gmail.com; Silva, Juliana Horie; Holtz, João Vitor; Ueda, Leandro; Abreu, Marilia; Marques, Carlindo; Machado, Leonardo [Instituto Dante Pazzanese de Cardiologia, São Paulo, SP - Brazil Mailing (Brazil)

    2015-08-15

    Cardiovascular disease is a leading cause of death in the world and in Brazil. Myocardial scintigraphy is an important noninvasive method for detecting ischemia in symptomatic patients, but its use in asymptomatic ones or those with atypical symptoms is yet to be defined. To verify the presence of major cardiac events in asymptomatic patients or those with atypical symptoms (atypical chest pain or dyspnea) that underwent myocardial scintigraphy (MS), over a period of 8 years. Secondary objectives were to identify cardiac risk factors associated with myocardial scintigraphy abnormalities and possible predictors for major cardiac events in this group. This was a retrospective, observational study using the medical records of 892 patients that underwent myocardial scintigraphy between 2005 and 2011 and who were followed until 2013 for assessment of major cardiac events and risk factors associated with myocardial scintigraphy abnormalities. Statistical analysis was performed by Fisher’s exact test, logistic regression and Kaplan-Meyer survival curves, with statistical significance being set at p ≤ 0.05. Of the total sample, 52.1% were men, 86.9% were hypertensive, 72.4% had hyperlipidemia, 33.6% were diabetic, and 12.2% were smokers; 44.5% had known coronary artery disease; and 70% had high Framingham score, 21.8% had moderate and 8% had low risk. Of the myocardial scintigraphies, 58.6% were normal, 26.1% suggestive of fibrosis and 15.3% suggestive of ischemia. At evolution, 13 patients (1.5%) had non-fatal myocardial infarction and six individuals (0.7%) died. The group with normal myocardial scintigraphy showed longer period of time free of major cardiac events, non-fatal myocardial infarction (p = 0.036) and death. Fibrosis in the myocardial scintigraphy determined a 2.4-fold increased risk of non-fatal myocardial infarction and five-fold higher risk of death (odds ratio: 2.4 and 5.7, respectively; p = 0.043). The occurrence of major cardiac events in 8 years

  3. Myocardial Scintigraphy in the Evaluation of Cardiac Events in Patients without Typical Symptoms

    Directory of Open Access Journals (Sweden)

    Paola Emanuela Poggio Smanio

    2015-01-01

    Full Text Available Background: Cardiovascular disease is a leading cause of death in the world and in Brazil. Myocardial scintigraphy is an important noninvasive method for detecting ischemia in symptomatic patients, but its use in asymptomatic ones or those with atypical symptoms is yet to be defined. Objective: To verify the presence of major cardiac events in asymptomatic patients or those with atypical symptoms (atypical chest pain or dyspnea that underwent myocardial scintigraphy (MS, over a period of 8 years. Secondary objectives were to identify cardiac risk factors associated with myocardial scintigraphy abnormalities and possible predictors for major cardiac events in this group. Methods: This was a retrospective, observational study using the medical records of 892 patients that underwent myocardial scintigraphy between 2005 and 2011 and who were followed until 2013 for assessment of major cardiac events and risk factors associated with myocardial scintigraphy abnormalities. Statistical analysis was performed by Fisher’s exact test, logistic regression and Kaplan-Meyer survival curves, with statistical significance being set at p ≤ 0.05. Results: Of the total sample, 52.1% were men, 86.9% were hypertensive, 72.4% had hyperlipidemia, 33.6% were diabetic, and 12.2% were smokers; 44.5% had known coronary artery disease; and 70% had high Framingham score, 21.8% had moderate and 8% had low risk. Of the myocardial scintigraphies, 58.6% were normal, 26.1% suggestive of fibrosis and 15.3% suggestive of ischemia. At evolution, 13 patients (1.5% had non-fatal myocardial infarction and six individuals (0.7% died. The group with normal myocardial scintigraphy showed longer period of time free of major cardiac events, non-fatal myocardial infarction (p = 0.036 and death. Fibrosis in the myocardial scintigraphy determined a 2.4-fold increased risk of non-fatal myocardial infarction and five-fold higher risk of death (odds ratio: 2.4 and 5.7, respectively; p = 0

  4. Quantitative evaluation of myocardial fibrosis by cardiac integrated backscatter analysis in Kawasaki disease.

    Science.gov (United States)

    Xie, Lijian; Wang, Renjian; Huang, Min; Zhang, Yongwei; Shen, Jie; Xiao, Tingting

    2016-01-12

    Kawasaki disease is an acute, systemic vasculitis that affects the coronary arteries. However, the relationship between myocardial fibrosis and Kawasaki disease has been completely unknown until now. We aimed to provide quantitative information about myocardial fibrosis using cardiac integrated backscatter in Han race Kawasaki disease patients. Ninety Kawasaki disease patients and 90 healthy control subjects were recruited. Based on Kawasaki disease status, the patients were categorized into 3 groups: acute, subacute, and convalescence phase. Based on coronary artery status, the Kawasaki disease patients were categorized into 3 groups: without coronary artery lesions, with coronary artery dilation, and with coronary artery aneurysms. All subjects underwent two-dimensional and Doppler examinations to measure clinical echocardiographic parameters. Myocardial fibrosis was detected with calibrated integrated backscatter imaging. Left ventricle systolic functions were normal in both the Kawasaki disease and control participants. The myocardial calibrated integrated backscatter values of the left ventricles of the acute (p Kawasaki disease patients were significantly greater than those of the healthy controls. The left ventricle myocardial calibrated integrated backscatter values were significantly smaller in the Kawasaki disease patients without coronary artery lesions than in the Kawasaki disease patients with coronary artery dilations and coronary artery aneurysms in different phases. The left ventricle myocardial calibrated integrated backscatter results were positively correlated with coronary artery status in the acute (r = 0.331, p Kawasaki disease. Our findings may suggest that myocardial fibrosis occurs during early episodes of Kawasaki disease given uncertainties that exist regarding correlations of calibrated integrated backscatter and myocardial fibrosis.

  5. An automated in vitro model for the evaluation of ultrasound modalities measuring myocardial deformation

    Directory of Open Access Journals (Sweden)

    Stigö Albin

    2010-09-01

    Full Text Available Abstract Background Echocardiography is the method of choice when one wishes to examine myocardial function. Qualitative assessment of the 2D grey scale images obtained is subjective, and objective methods are required. Speckle Tracking Ultrasound is an emerging technology, offering an objective mean of quantifying left ventricular wall motion. However, before a new ultrasound technology can be adopted in the clinic, accuracy and reproducibility needs to be investigated. Aim It was hypothesized that the collection of ultrasound sample data from an in vitro model could be automated. The aim was to optimize an in vitro model to allow for efficient collection of sample data. Material & Methods A tissue-mimicking phantom was made from water, gelatin powder, psyllium fibers and a preservative. Sonomicrometry crystals were molded into the phantom. The solid phantom was mounted in a stable stand and cyclically compressed. Peak strain was then measured by Speckle Tracking Ultrasound and sonomicrometry. Results We succeeded in automating the acquisition and analysis of sample data. Sample data was collected at a rate of 200 measurement pairs in 30 minutes. We found good agreement between Speckle Tracking Ultrasound and sonomicrometry in the in vitro model. Best agreement was 0.83 ± 0.70%. Worst agreement was -1.13 ± 6.46%. Conclusions It has been shown possible to automate a model that can be used for evaluating the in vitro accuracy and precision of ultrasound modalities measuring deformation. Sonomicrometry and Speckle Tracking Ultrasound had acceptable agreement.

  6. [Evaluation of fibrinolysis with streptokinase in ST-elevation myocardial infarction admitted to emergency department].

    Science.gov (United States)

    Bouhajja, Bechir; Souissi, Sami; Ghazali, Hanene; Yahmadi, Anouar; Mougaida, Moez; Laamouri, Noura; Sellami, Ali; Chkir, Mahbouba

    2014-02-01

    Fibrinolysis during ST elevation myocardial infarction (STEMI) is feasible in the emergency departments (ED), and this reduces the delay from first medical contact to coronary reperfusion. The aim of the study is to: 1) Evaluate fibrinolysis with streptokinase (SK) in STEMI admitted to the ED. 2) identify clinical criteria predictive of fibrinolysis success. prospective study (July 2008-March 2012). Inclusion of STEMI thrombolysed by SK. Fibrinolysis success was defined according to clinical and Electrocardiogram criteria. Multivariate study is used to identify the factors associated with thrombolysis success. Out of the 329 STEMI enrolled during the study period, 224 (68%) were thrombolysed. Mean age = 57 ± 11 years (20-86 years) sex ratio = 6. The average time chest pain - emergency admission was 195 ± 177 min (15 min to 12 hours). The 2/3 of patients had consulted during the first 3 hours. The average success rate of thrombolysis was 59% and reached 83% the first hour, 66% the second hour and 58.7% the third hour. In multivariate analysis, the three independent predictors factors of a fibrinolysis success were: active smoking, current treatment with beta blockers and the delay from onset chest pain to the ED visit less than 180 min. Conversely, diabetes was associated with fibrinolysis failure. Fibrinolysis got complicated by two intracerebral hemorrhages. Three patients had died in the ED. Two thirds of patients with STEMI have consulted 3 h after onset of chest pain. Fibrinolysis with streptokinase was effective in 59% of cases.

  7. Microheterogeneity of regional myocardial blood flows in low-perfused rat hearts evaluated by double-tracer digital radiography

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Takeshi [Bioengineering Division, Osaka University Graduate School of Engineering Science, Machikaneyamacho 13, Toyonaka 5608531 (Japan)]. E-mail: matsu@me.es.osaka-u.ac.jp; Asano, Takahisa [Department of Medical Engineering and Systems Cardiology, Kawasaki Medical School Matsushima 577, Kurashiki 7010192 (Japan); Takemoto, Mami [Department of Medical Engineering and Systems Cardiology, Kawasaki Medical School Matsushima 577, Kurashiki 7010192 (Japan); Tachibana, Hiroyuki [Department of Medical Engineering and Systems Cardiology, Kawasaki Medical School Matsushima 577, Kurashiki 7010192 (Japan); Ogasawara, Yasuo [Department of Medical Engineering and Systems Cardiology, Kawasaki Medical School Matsushima 577, Kurashiki 7010192 (Japan); Kajiya, Fumihiko [Department of Medical Engineering and Systems Cardiology, Kawasaki Medical School Matsushima 577, Kurashiki 7010192 (Japan)

    2007-08-15

    Using {sup 3}H- and {sup 125}I-labeled desmethylimipramine (DMI) for regional flow tracers, we established a two-time measurement method for the spatial pattern of myocardial perfusion in cross-circulated rat hearts. Myocardial extractions and retentions of these tracers were confirmed to be satisfactory; however, the latter were less than 90% after 3 min at a perfusion rate of 2.9 ml/min/g, limiting the present application to a short-time perfusion measurement. Distributions of myocardial depositions were separated by subtraction digital radiography with 400-{mu}m pixel resolution. Its feasibility was examined by regression analysis between local deposition densities of {sup 3}H- and {sup 125}I-DMI injected simultaneously. The slope, y-intercept, and correlation coefficient (r) of the regression line were 0.98{+-}0.04, 0.02{+-}0.04, and 0.95{+-}0.03, respectively, indicating the validity of the present image subtraction technique. The spatial pattern of myocardial perfusion in response to flow reduction was evaluated by the injections of {sup 3}H- and {sup 125}I-DMI, respectively, before and after a nearly 70% flow reduction. A significant correlation between normalized density distributions of these tracers was found in both subepicardium (r=0.77{+-}0.12) and subendocardium (r=0.73{+-}0.20), indicating the stable pattern of myocardial perfusion. However, the coefficient of variation of tracer densities showed a decrease of subendocardial flow heterogeneity from 35{+-}15% to 31{+-}16%. Thus, flow differences between originally high- and low-flow regions in subendocardium were reduced on a relative basis during low perfusion.

  8. Direct evaluation of myocardial viability and stem cell engraftment demonstrates salvage of the injured myocardium.

    Science.gov (United States)

    Kim, Paul J; Mahmoudi, Morteza; Ge, Xiaohu; Matsuura, Yuka; Toma, Ildiko; Metzler, Scott; Kooreman, Nigel G; Ramunas, John; Holbrook, Colin; McConnell, Michael V; Blau, Helen; Harnish, Phillip; Rulifson, Eric; Yang, Phillip C

    2015-03-27

    The mechanism of functional restoration by stem cell therapy remains poorly understood. Novel manganese-enhanced MRI and bioluminescence reporter gene imaging were applied to follow myocardial viability and cell engraftment, respectively. Human-placenta-derived amniotic mesenchymal stem cells (AMCs) demonstrate unique immunoregulatory and precardiac properties. In this study, the restorative effects of 3 AMC-derived subpopulations were examined in a murine myocardial injury model: (1) unselected AMCs, (2) ckit(+)AMCs, and (3) AMC-derived induced pluripotent stem cells (MiPSCs). To determine the differential restorative effects of the AMC-derived subpopulations in the murine myocardial injury model using multimodality imaging. SCID (severe combined immunodeficiency) mice underwent left anterior descending artery ligation and were divided into 4 treatment arms: (1) normal saline control (n=14), (2) unselected AMCs (n=10), (3) ckit(+)AMCs (n=13), and (4) MiPSCs (n=11). Cardiac MRI assessed myocardial viability and left ventricular function, whereas bioluminescence imaging assessed stem cell engraftment during a 4-week period. Immunohistological labeling and reverse transcriptase polymerase chain reaction of the explanted myocardium were performed. The unselected AMC and ckit(+)AMC-treated mice demonstrated transient left ventricular functional improvement. However, the MiPSCs exhibited a significantly greater increase in left ventricular function compared with all the other groups during the entire 4-week period. Left ventricular functional improvement correlated with increased myocardial viability and sustained stem cell engraftment. The MiPSC-treated animals lacked any evidence of de novo cardiac differentiation. The functional restoration seen in MiPSCs was characterized by increased myocardial viability and sustained engraftment without de novo cardiac differentiation, indicating salvage of the injured myocardium. © 2015 American Heart Association, Inc.

  9. [Evaluation of transfer parameters in patients admitted to our hospital with ST-elevation myocardial infarction].

    Science.gov (United States)

    Başar, Cengiz; Özhan, Hakan; Albayrak, Enver Sinan; Türker, Yasin

    2016-01-01

    Acute coronary syndrom (ACS) is a common disease that causes severe morbidity and mortality. The most important aspect of ST-elevation myocardial infarction (STEMI) as a subgroup of ACS treatment is the rapid reperfusion of arteries. Successful results depend not only on the experience of the center but also on the rapidity in which reperfusion is achieved. In our study, the transfer parameters were evaluated in patients who were admitted to our hospital with STEMI. Two hundred consecutive patients (160 males, 40 females) who underwent primary percutaneous coronary intervention (PCI) for acute STEMI between January 2011 and March 2013 were included in our study. Transfer parameters of symptom-to-reperfusion treatment, clinical characteristics, and laboratory parameters were recorded. Thirty-six patients were admitted to our hospital with ambulances; 70 patients were admitted to centers without PCI capability, with a mean transfer time to our hospital of 73.9±12.5 min. Median pain-to-first medical contact time was 105 min (range: 5-600 min), and average first medical contact-to-balloon time was 115.5 min (range: 20-414 min). Total pain-to-balloon time in females was significantly higher than males (246 min [range: 70-840 min], 195 min [range: 45-684 min], respectively, p=0.032). Mean pain-to-balloon time was significantly lower in patients delivered to the hospital by ambulance than in patients admitted to emergency departments independently (185 min [range: 45-439 min], 248 min [range: 65-840 min], respectively, p=0.017). In this study, our hospital door-to-balloon time was found compatible with the target specified in the European Society of Cardiology and American College of Cardiology STEMI guidelines; however, first medical contact-to-balloon time was found to be above that advised by the current guidelines.

  10. Aerobic Training after Myocardial Infarction: Remodeling Evaluated by Cardiac Magnetic Resonance

    Energy Technology Data Exchange (ETDEWEB)

    Izeli, Nataly Lino; Santos, Aurélia Juliana dos; Crescêncio, Júlio César; Gonçalves, Ana Clara Campagnolo Real; Papa, Valéria; Marques, Fabiana [Divisão de Cardiologia do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto - USP, Ribeirão Preto, SP (Brazil); Pazin-Filho, Antônio [Divisão de Emergência da Faculdade de Medicina de Ribeirão Preto - USP, Ribeirão Preto, SP (Brazil); Gallo-Júnior, Lourenço; Schmidt, André, E-mail: aschmidt@fmrp.usp.br [Divisão de Cardiologia do Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto - USP, Ribeirão Preto, SP (Brazil)

    2016-04-15

    Numerous studies show the benefits of exercise training after myocardial infarction (MI). Nevertheless, the effects on function and remodeling are still controversial. To evaluate, in patients after (MI), the effects of aerobic exercise of moderate intensity on ventricular remodeling by cardiac magnetic resonance imaging (CMR). 26 male patients, 52.9 ± 7.9 years, after a first MI, were assigned to groups: trained group (TG), 18; and control group (CG), 8. The TG performed supervised aerobic exercise on treadmill twice a week, and unsupervised sessions on 2 additional days per week, for at least 3 months. Laboratory tests, anthropometric measurements, resting heart rate (HR), exercise test, and CMR were conducted at baseline and follow-up. The TG showed a 10.8% reduction in fasting blood glucose (p = 0.01), and a 7.3-bpm reduction in resting HR in both sitting and supine positions (p < 0.0001). There was an increase in oxygen uptake only in the TG (35.4 ± 8.1 to 49.1 ± 9.6 mL/kg/min, p < 0.0001). There was a statistically significant decrease in the TG left ventricular mass (LVmass) (128.7 ± 38.9 to 117.2 ± 27.2 g, p = 0.0032). There were no statistically significant changes in the values of left ventricular end-diastolic volume (LVEDV) and ejection fraction in the groups. The LVmass/EDV ratio demonstrated a statistically significant positive remodeling in the TG (p = 0.015). Aerobic exercise of moderate intensity improved physical capacity and other cardiovascular variables. A positive remodeling was identified in the TG, where a left ventricular diastolic dimension increase was associated with LVmass reduction.

  11. Evaluation of Survival Rate and Effective Factors in Acute Myocardial Infarction Patients in Emam Hospital (Year 2000

    Directory of Open Access Journals (Sweden)

    M Maghsoodloo

    2002-09-01

    Full Text Available Introduction: For the time being we have considered that the myocardial infarction is an increasing event in Islamic Republic of Iran and there are many procedures and methods which can help us to diminish the number of death from this ongoing event. The main aim of this research is to determine the survival rate in those patients who have had acute myocardial infarction and the association of it with different variables. Methods and Materials: The present research is a descriptive case-series study which evaluates the 100 cases of acute myocardial infarction who had been admitted in Tehran Emam Khomeini Hospital during the year 1999. Results: The mean age of patients was 57 years. The peak of attack rates was in spring and autumn. Investigating of the past history of these patients reviled that 41 percent had been smokers, 63.5 percent have had the history of previous ischemic heart disease, 41 percent have had hyper cholestrolemia, 34 percent had hypertension, 18 percent had diabetes mellitus, 9 percent had mitral rigurgitation and 9 percent had heart block. The Survival rate in our study has been calculated 68 percent in first 28 days of disease. Conclusion: In our study we concluded that there is significant correlation between survival rate and past history of hypertension, ischemic heart disease, tobacco smoking and clip classification.

  12. Effect of verapamil on myocardial ischemia in patients with hypertrophic cardiomyopathy; Evaluation by exercise [sup 201]Tl SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Taniguchi, Yoko; Sugihara, Hiroki; Ootsuki, Katsuichi (Kyoto Prefectural Univ. of Medicine (Japan)) (and others)

    1993-01-01

    Effect of verapamil on myocardial ischemia in patients with hypertrophic cardiomyopathy (HCM) was evaluated by exercise stress myocardial [sup 201]Tl SPECT (EX-Tl). EX-Tl was performed before and after 8.8 weeks of oral verapamil (240 mg/day) in 12 patients with HCM who showed transient [sup 201]Tl perfusion defects under control conditions. [sup 201]Tl perfusion defect was visually scored and judged for 4 grades as normal (0), mild defect (1), moderate defect (2), and severe defect (3). Transient dilation index (TDI) was calculated as an index of subendocardial ischemia. Improvements of defect score were demonstrated in 10 patients after administration of verapamil. Two patients showed no change of defect score. Mean defect score decreased significantly from 5.50 to 3.03 (p<0.001). Although 11 of 12 patients showed abnormal TDI under control conditions, 10 of these revealed improvements of TDI and 7 of the 10 disclosed normal TDI after verapamil. Mean TDI decreased from 1.263 to 1.090 significantly (p<0.01). In conclusion, verapamil may improve myocardial ischemia in patients with HCM. (author).

  13. Shape anisotropy: tensor distance to anisotropy measure

    Science.gov (United States)

    Weldeselassie, Yonas T.; El-Hilo, Saba; Atkins, M. S.

    2011-03-01

    Fractional anisotropy, defined as the distance of a diffusion tensor from its closest isotropic tensor, has been extensively studied as quantitative anisotropy measure for diffusion tensor magnetic resonance images (DT-MRI). It has been used to reveal the white matter profile of brain images, as guiding feature for seeding and stopping in fiber tractography and for the diagnosis and assessment of degenerative brain diseases. Despite its extensive use in DT-MRI community, however, not much attention has been given to the mathematical correctness of its derivation from diffusion tensors which is achieved using Euclidean dot product in 9D space. But, recent progress in DT-MRI has shown that the space of diffusion tensors does not form a Euclidean vector space and thus Euclidean dot product is not appropriate for tensors. In this paper, we propose a novel and robust rotationally invariant diffusion anisotropy measure derived using the recently proposed Log-Euclidean and J-divergence tensor distance measures. An interesting finding of our work is that given a diffusion tensor, its closest isotropic tensor is different for different tensor distance metrics used. We demonstrate qualitatively that our new anisotropy measure reveals superior white matter profile of DT-MR brain images and analytically show that it has a higher signal to noise ratio than fractional anisotropy.

  14. Myocardial Ischemia

    Science.gov (United States)

    ... pectoris: Chest pain caused by myocardial ischemia. www.uptodate.com/home. Accessed June 1, 2015. Deedwania PC. Silent myocardial ischemia: Epidemiology and pathogenesis. www.uptodate.com/home. Accessed June 1, 2015. Mann DL, ...

  15. Magnetic surface anisotropy

    Science.gov (United States)

    Rado, George T.

    1992-02-01

    Selected aspects of magnetic surface anisotropy are reviewed. The emphasis is on methods for deducing reliable surface anisotropy values from experiments such as ferromagnetic resonance at microwave frequencies and Brillouin scattering at optical frequencies. The methods used are the "general exchange boundary condition method" and the "effective volume anisotropy method". The essence of the former is the supplementing of the equation of motion of the magnetization with the general exchange boundary condition whereas the latter consists of using the "stratagem" of effective volume anisotropy. We find that use of the general exchange boundary condition method is not only preferable in principle but often actually necessary to prevent the prediction of wrong surface anisotropy values and to permit the prediction of some observable Brillouin shifts.

  16. Electrocardiographic left ventricular hypertrophy without echocardiographic abnormalities evaluated by myocardial perfusion and fatty acid metabolic imaging

    Energy Technology Data Exchange (ETDEWEB)

    Narita, Michihiro; Kurihara, Tadashi [Sumitomo Hospital, Osaka (Japan)

    2000-01-01

    The pathophysiologic process in patients with electrocardiographic left ventricular hypertrophy with ST, T changes but without echocardiographic abnormalities was investigated by myocardial perfusion imaging and fatty acid metabolic imaging. Exercise stress {sup 99m}Tc-methoxy-isobutyl isonitrile (MIBI) imaging and rest {sup 123}I-beta-methyl-p-iodophenyl pentadecanoic acid (BMIPP) imaging were performed in 59 patients with electrocardiographic hypertrophy including 29 without apparent cause including hypertension and echocardiographic hypertrophy, and 30 with essential hypertension. Coronary angiography was performed in 6 patients without hypertension and 4 with hypertension and biopsy specimens were obtained from the left ventricular apex from 6 patients without hypertension. Myocardial perfusion and {sup 123}I-BMIPP images were classified into 3 types: normal, increased accumulation of the isotope at the left ventricular apex (high uptake) and defect. Transient perfusion abnormality and apical defect observed by {sup 123}I-BMIPP imaging were more frequent in patients without hypertension than in patients with hypertension (32% vs. 17%, p=0.04671 in perfusion; 62% vs. 30%, p=0.0236 in {sup 123}I-BMIPP). Eighteen normotensive patients with apical defect by {sup 123}I-BMIPP imaging included 3 of 10 patients with normal perfusion at exercise, 6 of 10 patients with high uptake and 9 of 9 patients with perfusion defect. The defect size revealed by {sup 123}I-BMIPP imaging was greater than that of the perfusion abnormality. Coronary stenoses were not observed and myocardial specimens showed myocardial disarray with hypertrophy. Moreover, 9 patients with hypertension and apical defects by {sup 123}I-BMIPP showed 3 different types of perfusion. Many patients without hypertension show a pathologic process similar to hypertrophic cardiomyopathy. Perfusion and {sup 123}I-BMIPP imaging are useful for the identification of these patients. (author)

  17. Influence of oxygen tension on myocardial performance. Evaluation by tissue Doppler imaging

    Directory of Open Access Journals (Sweden)

    Poulsen Steen

    2004-11-01

    Full Text Available Abstract Background Low O2 tension dilates coronary arteries and high O2 tension is a coronary vasoconstrictor but reports on O2-dependent effects on ventricular performance diverge. Yet oxygen supplementation remains first line treatment in cardiovascular disease. We hypothesized that hypoxia improves and hyperoxia worsens myocardial performance. Methods Seven male volunteers (mean age 38 ± 3 years were examined with echocardiography at respiratory equilibrium during: 1 normoxia (≈21% O2, 79% N2, 2 while inhaling a hypoxic gas mixture (≈11% O2, 89% N2, and 3 while inhaling 100% O2. Tissue Doppler recordings were acquired in the apical 4-chamber, 2-chamber, and long-axis views. Strain rate and tissue tracking displacement analyses were carried out in each segment of the 16-segment left ventricular model and in the basal, middle and apical portions of the right ventricle. Results Heart rate increased with hypoxia (68 ± 4 bpm at normoxia vs. 79 ± 5 bpm, P Conclusion Hypoxia improves and hyperoxia worsens systolic myocardial performance in healthy male volunteers. Tissue Doppler measures of diastolic function are unaffected by hypoxia/hyperoxia which support that the changes in myocardial performance are secondary to changes in vascular tone. It remains to be settled whether oxygen therapy to patients with heart disease is a consistent rational treatment.

  18. Diffuse myocardial fibrosis evaluation using cardiac magnetic resonance T1 mapping: sample size considerations for clinical trials

    Directory of Open Access Journals (Sweden)

    Liu Songtao

    2012-12-01

    Full Text Available Abstract Background Cardiac magnetic resonance (CMR T1 mapping has been used to characterize myocardial diffuse fibrosis. The aim of this study is to determine the reproducibility and sample size of CMR fibrosis measurements that would be applicable in clinical trials. Methods A modified Look-Locker with inversion recovery (MOLLI sequence was used to determine myocardial T1 values pre-, and 12 and 25min post-administration of a gadolinium-based contrast agent at 3 Tesla. For 24 healthy subjects (8 men; 29 ± 6 years, two separate scans were obtained a with a bolus of 0.15mmol/kg of gadopentate dimeglumine and b 0.1mmol/kg of gadobenate dimeglumine, respectively, with averaged of 51 ± 34 days between two scans. Separately, 25 heart failure subjects (12 men; 63 ± 14 years, were evaluated after a bolus of 0.15mmol/kg of gadopentate dimeglumine. Myocardial partition coefficient (λ was calculated according to (ΔR1myocardium/ΔR1blood, and ECV was derived from λ by adjusting (1-hematocrit. Results Mean ECV and λ were both significantly higher in HF subjects than healthy (ECV: 0.287 ± 0.034 vs. 0.267 ± 0.028, p=0.002; λ: 0.481 ± 0.052 vs. 442 ± 0.037, p Conclusion ECV and λ quantification have a low variability across scans, and could be a viable tool for evaluating clinical trial outcome.

  19. Recent advances of {sup 123}I-BMIPP myocardial SPECT for evaluating ischemic heart disease and cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, T. [Tracer Kinetics and Nuclear Medicine, Osaka Univ., Medical School (Japan)

    1998-12-31

    Recent advances of {sup 123}I-BMIPP myocardial SPECT for evaluating ischemic heart disease and cardiomyopathy were reviewed. The dissociation between BMIPP and thallium defects was frequently observed in patients with acute myocardial infarction with successful reperfusion. The degree and improvement of perfusion/metabolism mismatch may reflect subsequent recovery from postischemic wall motion abnormality. BMIPP myocardial SPECT is also sensitive for detecting myocardial ischemia in acute coronary syndrome. BMIPP defects were observed at sites that corresponded to hypertrophic cardiomyopathy. On the other hand, the dissociation between BMIPP and thallium defects was not observed frequently in dilated cardiomyopathy. However, the heart to the mediastinum ratio and defect score were significantly decreased after coenzyme Q10 treatment. It was confirmed to be sensitive in evaluating the therapeutic effect. Furthermore, the basic mechanisms of BMIPP uptake were also reviewed in relation to BMIPP metabolism and longchain fatty acid transporter (CD36). (orig.) [Deutsch] Es wird eine Uebersicht ueber neueste Entwicklungen der {sup 123}I-BMIPP-Myokard-SPECT fuer die Diagnostik ischaemischer Herzerkrankungen und der Kardiomyopathie praesentiert. Regelmaessig wurde eine Dissoziation zwischen BMIPP- und Thallium-Defekten bei Patienten mit akutem Myokardinfarkt und erfolgreicher Reperfusion beobachtet. Die BMIPP-Aufnahme ist also im erfolgreich therapierten Myokard unmittelbar nach der Reperfusion gestoert, obwohl die Durchblutung wiederhergestellt wurde. Der Grad und die Entwicklung der Perfusions-Stoffwechsel-Mismatche repraesentieren eine spaetere Erholung von der postischaemischen Wandbewegungsstoerung. Die Ruhe-BMIPP-SPECT ist ein sehr sensitives Verfahren, um die Myokardischaemie beim akuten Koronarsyndrom zu erfassen. Diese Methoden sind unter dem Aspekt der Myokardvitalitaet beim Notfallpatienten fuer das Patientenmanagement wertvoll. In 80% der Patienten mit

  20. [Evaluation of myocardial viability with 201Tl/18F-FDG DISA-SPECT technique in patients with acute myocardial infarction after emergent intracoronary autologous bone marrow mononuclear cells transplantation].

    Science.gov (United States)

    Huang, Rong-chong; Yao, Kang; Qian, Ju-ying; Niu, Yu-hong; Ge, Lei; Chen, Shu-guang; Shi, Hong-cheng; Zhang, Yi-Qi; Sun, Ai-jun; Wang, Ke-qiang; Zou, Yun-zeng; Ge, Jun-bo

    2007-06-01

    To evaluate the myocardial viability with (201)Tl/(18)F-FDG DISA-SPECT technique in patients with acute myocardial infarction underwent emergent intracoronary autologous bone marrow mononuclear cells (BM-MNC) transplantation. Patients with first acute myocardial infarction underwent emergent percutaneous coronary intervention (PCI) were randomized in a 1:1 ratio to either intracoronary transplantation of autologous BM-MNC (n = 20) or to sodium chloride concluding heparin (control, n = 20) via a micro infusion catheter group immediately after PCI. Change in global left ventricular function (LVEF measured by echocardiography) and the myocardial viability detected by (201)Tl/(18)F-FDG DISA-SPECT from baseline and 6-months post transplantation were analyzed. Left ventricular ejection fraction (LVEF) was improved in both groups and the absolute increase (DeltaLVEF) in BM-MNC group was significantly higher than that in control group (7.6% +/- 2.8% vs. 3.0% +/- 2.8%, P DISA-SPECT technique.

  1. Significance of exercise-induced ST segment depression in patients with myocardial infarction involving the left circumflex artery. Evaluation by exercise thallium-201 myocardial single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Koitabashi, Norimichi; Toyama, Takuji; Hoshizaki, Hiroshi [Gunma Prefectural Cardiovascular Center, Maebashi (Japan)] [and others

    2000-04-01

    The significance of exercise-induced ST segment depression in patients with left circumflex artery involvement was investigated by comparing exercise electrocardiography with exercise thallium-201 single photon emission computed tomography (Tl-SPECT) and the wall motion estimated by left ventriculography. Tl-SPECT and exercise electrocardiography were simultaneously performed in 51 patients with left circumflex artery involvement (angina pectoris 30, myocardial infarction 21). In patients with myocardial infarction, exercise-induced ST depression was frequently found in the V{sub 2}, V{sub 3} and V{sub 4} leads. In patients with angina pectoris, ST depression was frequently found in the II, III, aV{sub F}, V{sub 5} and V{sub 6} leads. There was no obvious difference in the leads of ST depression in patients with myocardial infarction with ischemia and without ischemia on Tl-SPECT images. In patients with myocardial infarction, the lateral wall motion of the infarcted area evaluated by left ventriculography was more significantly impaired in the patients with ST depression than without ST depression (p<0.01). Exercise-induced ST depression in the precordial leads possibly reflects wall motion abnormality rather than ischemia in the lateral infarcted myocardium. (author)

  2. Image quality improvements using adaptive statistical iterative reconstruction for evaluating chronic myocardial infarction using iodine density images with spectral CT.

    Science.gov (United States)

    Kishimoto, Junichi; Ohta, Yasutoshi; Kitao, Shinichiro; Watanabe, Tomomi; Ogawa, Toshihide

    2017-10-19

    Single-source dual-energy CT (ssDECT) allows the reconstruction of iodine density images (IDIs) from projection based computing. We hypothesized that adding adaptive statistical iterative reconstruction (ASiR) could improve image quality. The aim of our study was to evaluate the effect and determine the optimal blend percentages of ASiR for IDI of myocardial late iodine enhancement (LIE) in the evaluation of chronic myocardial infarction using ssDECT. A total of 28 patients underwent cardiac LIE using a ssDECT scanner. IDIs between 0 and 100% of ASiR contributions in 10% increments were reconstructed. The signal-to-noise ratio (SNR) of remote myocardia and the contrast-to-noise ratio (CNR) of infarcted myocardia were measured. Transmural extent of infarction was graded using a 5-point scale. The SNR, CNR, and transmural extent were assessed for each ASiR contribution ratio. The transmural extents were compared with MRI as a reference standard. Compared to 0% ASiR, the use of 20-100% ASiR resulted in a reduction of image noise (p ASiR images, reconstruction with 100% ASiR image showed the highest improvement in SNR (229%; p ASiR above 80% showed the highest ratio (73.7%) of accurate transmural extent classification. In conclusion, ASiR intensity of 80-100% in IDIs can improve image quality without changes in signal and maximizes the accuracy of transmural extent in infarcted myocardium.

  3. Evaluation of Patients with Acute Chest Pain Using SPECT Myocardial Perfusion Imaging: Prognostic Implications of Mildly Abnormal Scans.

    Science.gov (United States)

    Goldkorn, Ronen; Naimushin, Alexey; Beigel, Roy; Naimushin, Ekaterina; Narodetski, Michael; Matetzky, Shlomi

    2017-06-01

    While patients presenting to emergency departments (ER) with chest pain are increasingly managed in chest pain units (CPU) that utilize accelerated diagnostic protocols for risk stratification, such as single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI), data are lacking regarding the prognostic implications of mildly abnormal scans in this population. To evaluate the prognostic implications of mildly abnormal SPECT MPI results in patients with acute chest pain. Of the 3753 chest pain patients admitted to the CPU at the Leviev Heart Center, Sheba Medical Center 1593 were further evaluated by SPECT MPI. Scans were scored by extent and severity of stress-induced perfusion defects, with 1221 patients classified as normal, 82 with myocardial infarction without ischemia, 236 with mild ischemia, and 54 with more than mild ischemia. Mild ischemia patients were further classified to those who did and did not undergo coronary angiography within 7 days. Mild ischemia patients who underwent coronary angiography were more likely to be male (92% vs. 81%, P = 0.01) and to have left anterior descending ischemia (67% vs. 42%, P = 0.004). After 50 months, these patients returned less often to the ER with chest pain (53% vs. 87%, P acute coronary syndrome and death (8% vs. 16%, P patients with chronic stable angina, patients presenting with acute chest pain exhibiting mildly abnormal SPECT MPI findings should perhaps undergo a more aggressive diagnostic and therapeutic approach.

  4. Evaluation of cardioprotective effect of aqueous extract of Garcinia indica Linn. fruit rinds on isoprenaline-induced myocardial injury in Wistar albino rats.

    Science.gov (United States)

    Patel, Kaksha J; Panchasara, Ashwin K; Barvaliya, Manish J; Purohit, Bhargav M; Baxi, Seema N; Vadgama, Vishal K; Tripathi, C B

    2015-01-01

    In the present study, cardioprotective effect of aqueous extract of Garcinia indica Linn. fruit rinds in isoprenaline-induced myocardial infarction in Wistar albino rats was evaluated. In vitro total phenolic, total flavonoid content and 2, 2'-diphenyl-1-picrylhydrazyl hydrate radical scavenging activity was measured. In vivo effect of aqueous extract of G. indica was evaluated in Wistar albino rats by isoprenaline-induced myocardial injury model. Thirty six rats were randomly divided in 6 groups. Rats were treated with G. indica 250 mg/kg and 500 mg/kg doses for 21 days and myocardial injury was produced by subcutaneous injection of isoprenaline 85 mg/kg on day 20 and 21. Carvedilol 1 mg/kg for 21 days served as active control. Electrocardiogram parameters, cardiac injury markers (serum troponin-I, uric acid, lactate dehydrogenase, creatinine kinase-MB, aspartate aminotransferase and alanine aminotransferase), oxidative stress markers (superoxide dismutase, catalase and malondialdehyde level) and histopathological changes were evaluated in each group and compared using appropriate statistical tests. In vitro evaluation of aqueous extract showed significant antioxidant property. Isoprenaline produced significant myocardial ischemia as compared to normal control group (Pindica in both the doses did not significantly recover the altered electrocardiogram, cardiac injury markers, oxidative stress markers and histopathological myocardial damage as compared to disease control group (P>0.05). The aqueous extract of G. indica was not found to be cardioprotective against myocardial injury. Further study with more sample size and higher dose range may be required to evaluate its cardioprotective effect.

  5. Nonculprit Stenosis Evaluation Using Instantaneous Wave-Free Ratio in Patients With ST-Segment Elevation Myocardial Infarction

    DEFF Research Database (Denmark)

    Thim, Troels; Götberg, Matthias; Fröbert, Ole

    2017-01-01

    OBJECTIVES: The aim of this study was to examine the level of agreement between acute instantaneous wave-free ratio (iFR) measured across nonculprit stenoses in patients with ST-segment elevation myocardial infarction (STEMI) and iFR measured at a staged follow-up procedure. BACKGROUND: Acute full...... revascularization of nonculprit stenoses in STEMI is debated and currently guided by angiography. Acute functional assessment of nonculprit stenoses may be considered. METHODS: Immediately after successful primary culprit intervention for STEMI, nonculprit coronary stenoses were evaluated with iFR and left...... untreated. Follow-up evaluation with iFR was performed at a later stage. iFR acute iFR was 0.89 (interquartile range: 0.82 to 0.94; n = 156), and median follow-up i...

  6. Evaluation of group versus individual nutrition education in overweight patients with myocardial infarction.

    Science.gov (United States)

    Wright, J; Wood, B; Hale, G

    1981-10-01

    Thirty-nine obese patients (weighing in excess of 110% of ideal weight) were studied for 52 weeks following admission to the Coronary Care Unit with a diagnosis of acute myocardial infarction. The aim of the study was to compare, chiefly by anthropometric measurements, the response to a structured nutrition education program provided by a dietitian using three different levels of time involvement with the patients, firstly individual patient education, secondly group education and thirdly the issuing of written material only. Although there was no significant difference in the mean weight loss between the three education groups (8.1, 7.5 and 8.9 kg respectively) there was a trend towards more uniform weight reduction in those who received individual education. All but two of the 28 who attended at 52 weeks achieved weight loss. Thirteen patients attained 110% or less of their ideal weight, a 46% success rate. Reduction in body weight and most of the other anthropometric measurements occurred in the first twelve weeks of study, with no further significant weight change to 52 weeks. While these observations suggest that the overweight patient with acute myocardial infarction need not be subject to intensive nutrition education at the time of presentation, a more aggressive follow-up programme in subsequent months is recommended.

  7. Transthoracic coronary flow reserve and dobutamine derived myocardial function: a 6-month evaluation after successful coronary angioplasty

    Directory of Open Access Journals (Sweden)

    Pardo Moira

    2004-12-01

    Full Text Available Abstract After percutaneous transluminal coronary angioplasty (PTCA, stress-echocardiography and gated single photon emission computerized tomography (g-SPECT are usually performed but both tools have technical limitations. The present study evaluated results of PTCA of left anterior descending artery (LAD six months after PTCA, by combining transthoracic Doppler coronary flow reserve (CFR and color Tissue Doppler (C-TD dobutamine stress. Six months after PTCA of LAD, 24 men, free of angiographic evidence of restenosis, underwent standard Doppler-echocardiography, transthoracic CFR of distal LAD (hyperemic to basal diastolic coronary flow ratio and C-TD at rest and during dobutamine stress to quantify myocardial systolic (Sm and diastolic (Em and Am, Em/Am ratio peak velocities in middle posterior septum. Patients with myocardial infarction, coronary stenosis of non-LAD territory and heart failure were excluded. According to dipyridamole g-SPECT, 13 patients had normal perfusion and 11 with perfusion defects. The 2 groups were comparable for age, wall motion score index (WMSI and C-TD at rest. However, patients with perfusion defects had lower CFR (2.11 ± 0.4 versus 2.87 ± 0.6, p m at high-dose dobutamine (p m of middle septum (r = 0.55, p In conclusion, even in absence of epicardial coronary restenosis, stress perfusion imaging reflects a physiologic impairment in coronary microcirculation function whose magnitude is associated with the degree of regional functional impairment detectable by C-TD.

  8. Effects of MR parameter changes on the quantification of diffusion anisotropy and apparent diffusion coefficient in diffusion tensor imaging: evaluation using a diffusional anisotropic phantom.

    Science.gov (United States)

    Kim, Sang Joon; Choi, Choong Gon; Kim, Jeong Kon; Yun, Sung-Cheol; Jahng, Geon-Ho; Jeong, Ha-Kyu; Kim, Eun Ju

    2015-01-01

    To validate the usefulness of a diffusional anisotropic capillary array phantom and to investigate the effects of diffusion tensor imaging (DTI) parameter changes on diffusion fractional anisotropy (FA) and apparent diffusion coefficient (ADC) using the phantom. Diffusion tensor imaging of a capillary array phantom was performed with imaging parameter changes, including voxel size, number of sensitivity encoding (SENSE) factor, echo time (TE), number of signal acquisitions, b-value, and number of diffusion gradient directions (NDGD), one-at-a-time in a stepwise-incremental fashion. We repeated the entire series of DTI scans thrice. The coefficients of variation (CoV) were evaluated for FA and ADC, and the correlation between each MR imaging parameter and the corresponding FA and ADC was evaluated using Spearman's correlation analysis. The capillary array phantom CoVs of FA and ADC were 7.1% and 2.4%, respectively. There were significant correlations between FA and SENSE factor, TE, b-value, and NDGD, as well as significant correlations between ADC and SENSE factor, TE, and b-value. A capillary array phantom enables repeated measurements of FA and ADC. Both FA and ADC can vary when certain parameters are changed during diffusion experiments. We suggest that the capillary array phantom can be used for quality control in longitudinal or multicenter clinical studies.

  9. Myocardial Bridging

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2016-02-01

    Full Text Available Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

  10. Evaluation of myocardial viability in old myocardial infarcted patients with CHF: delayed enhancement MRI vs. low-dose dobutamine stress speckle tracking echocardiography.

    Science.gov (United States)

    Wang, Chaofan; Han, Shuguang; Xu, Tongda; Wang, Fengli; Wang, Xiaoping; Chen, Jing; Hu, Chunfeng; Li, Dongye

    2016-01-01

    The aim of this study was to explore the significance of delayed enhancement magnetic resonance imaging (DE-MRI) combined with two-dimensional speckle tracking echocardiography (STE) and low dose dobutamine stress echocardiography (LDDSE) to assess viable myocardium (VM) in the patients with old myocardial infarction (OMI) associated with congestive heart failure (CHF). Thirty five hospitalized OMI patients with regional wall motion abnormalities and left ventricular ejection fraction (LVEF) CHF.

  11. Two-dimensional strain echocardiography technology for evaluation of myocardial strain in swimming athletes after high-intensity exercise.

    Science.gov (United States)

    Liang, Chen; Ma, Yun; Gao, Can; Zhang, Jianhong; Yang, Min; Chen, Gen; Fu, Shan; Zhu, Tiangang

    2017-02-01

    The aim of this study was to investigate the change in myocardial strain in swimming athletes before and after high-intensity exercise using two-dimensional strain echocardiography (2DSE) technology. To assess whether the local and overall myocardial function and myocardial injury are accurately measured using 2DSE technology, 15 swimming athletes were selected as research objects. We applied 2DSE technology to track the 2D ultrasound images of the apical four chambers, the apical two chambers, and the apical long axis before and after high-intensity, increasing-load exercise. We recorded indices such as the left ventricular global strain (GS) and the left ventricular segmental wall longitudinal peak systolic strain (PS) in 18 systoles and analyzed the myocardial strain change before and after exercise. After high-intensity exercise, the overall myocardial strain decreased, especially the strain of the posterior wall, posterior divider, lateral wall, lower wall, and the basal and middle segments of the anterior wall. The influence of exercise on myocardial strain was greater on the basal and middle segments than on the apical segment. One-time intensive exercise negatively affected the myocardial muscle. Myocardial muscles in the apical segment and the myocardial wall were more sensitive to intensive exercise. The 2DSE technology can precisely position the motion-sensitive areas and help locate myocardial injury. © 2017, Wiley Periodicals, Inc.

  12. Technetium myocardial perfusion scanning in prerenal transplant evaluation in the United kingdom.

    LENUS (Irish Health Repository)

    Wong, C F

    2008-06-01

    Because death with a functioning graft remains one of the most important causes of long-term renal transplant failure, cardiac risk stratification and screening for coronary artery disease are essential components of pretransplant assessment. Pretransplant screening for occult coronary artery disease in a subset of these patients may improve outcome. The UK follows the European Best practice guideline 1.5.5 E. Although echocardiography, thallium myocardial perfusion scanning (MPS), dobutamine stress echocardiography, and coronary angiography have been suggested as means of cardiovascular assessment, the best means of assessment remains undetermined. Therefore, we investigated the role of 99m technetium sestamibi myocardial perfusion scanning as an assessment tool for identifying those patients with end-stage renal failure at high risk of cardiovascular death after renal transplantation. Retrospectively, we studied 126 patients that had a MPS as part of their pretransplant assessment. Overall unadjusted survival was 65% at 3 years. Twelve deaths resulted from cardiovascular causes. A reversible defect on MPS was associated with a fatal cardiac event and all-cause mortality. The unadjusted hazard ratio of cardiac event with reversible defect on MPS was 3.1 (95% confidence interval, 1.1 to 18.2) and hazard ratio of death with reversible defect on MPS was 1.92 (95% confidence interval, 1.1 to 4.4). Thus, MPS may be a useful tool in cardiac risk stratification and in selecting patients with a favorable outcome after renal transplantation. Our patients with a reversible defect in particular have increased cardiac mortality. This group may benefit from coronary angiography.

  13. Myocardial Ischemia

    Science.gov (United States)

    ... occurs when blood flow to the heart muscle (myocardium) is obstructed by a partial or complete blockage of a coronary artery by a buildup of plaques (atherosclerosis). If the plaques rupture, you can have a heart attack (myocardial infarction). Myocardial ischemia occurs when blood flow ...

  14. Differences in the architecture of low-grade and high-grade gliomas evaluated using fiber density index and fractional anisotropy.

    Science.gov (United States)

    Chen, Yiyong; Shi, Yonghong; Song, Zhijian

    2010-07-01

    Accurate pre-operative assessment of tumor grade is important for the selection of appropriate treatment strategies. The aim of this study was to retrospectively evaluate whether the fiber density index (FDi) and fractional anisotropy (FA) via diffusion tensor MRI (DTI) could assist with pre-operative diagnosis of glioma grade. A total of 31 patients who had histologically confirmed gliomas underwent DTI performed using a 1.5-Tesla magnetic resonance scanner. To reconstruct the white matter adjacent to the tumor, DTI fiber tracking (DTI-FT) using an FA threshold of 0.15 was implemented. Regions of interest (ROIs) were defined (i-iv) as: the tumor center (ROI i); white matter adjacent to the tumor (ROI ii); contralateral centrum semiovale (ROI iii); and the homologous fiber tracts to ROI ii in the contralateral hemisphere (ROI iv). We calculated six parameters from different ROIs and compared high-grade and low-grade gliomas: FA values and ratios; FDi values and ratios with an FA threshold of 0.15; and FDi values and ratios with an FA threshold of 0.25. The results showed that FA ratios and FDi ratios with FA thresholds of 0.25 were significantly different between patients with high-grade and low-grade gliomas. This may be useful for developing surgical strategies and appraising patient prognosis.

  15. Insight into asthenospheric seismic anisotropy and deformation in Mainland China

    Science.gov (United States)

    Zhu, Tao

    2017-04-01

    Seismic anisotropy can provide direct constrains on asthenospheric deformation which also can be induced by the inherent mantle flow within our planet. Mantle flow calculations thus have been an effective tool to probe asthenospheric anisotropy. The seismic anisotropy probed by shear wave splitting (SWS) dominantly displays single-layer anisotropy, which allows us to infer the asthenospheric source of SWS and qualitatively evaluate asthenospheric deformation using mantle flow calculations in Mainland China. To date, simple asthenospheric flow (SAF) model has commonly been used to probe asthenospheric anisotropy in Mainland China. This model yields the anisotropy aligning along the direction of absolute plate motion and actually does not consider the effects of mantle flow which is inherent within our planet. To our knowledge, mantle flow is of importance to seismic anisotropy since it may lead to observation-comparable geophysical fields and seismic anisotropy. Therefore, in order to evaluate the effects of mantle flow and probe the more proper interpretation on seismic anisotropy in Mainland China, mantle flow models driven by plate motion (plate-driven) and by a combination of plate motion and mantle density heterogeneity (plate-density-driven) are used to predict the fast polarization direction (FPD) of SWS. Our results indicate that: plate-driven or plate-density driven mantle flow has dramatic effects on the development of seismic anisotropy when compared with SAF; plate-driven flow controls the FPD and large-strain-induced anisotropy strength while thermal mantle flow dominates the anisotropy strength due to low strain; asthenospheric flow is an assignable contributor to seismic anisotropy, and the asthenosphere is undergoing low, large or moderate shear deformation controlled by the strain model, the flow plane/flow direction model or the both in most regions of central and eastern China; and the asthenosphere is under more rapid extension deformation in

  16. Cost-effectiveness evaluation of aspirin in primary prevention of myocardial infarction amongst males with average cardiovascular risk in Iran.

    Science.gov (United States)

    Amirsadri, Mohammadreza; Sedighi, Mohammad Javad

    2017-04-01

    Aspirin is one of the certified medicines commonly used for the secondary prevention of myocardial infarction (MI). Aspirin side effects and gastrointestinal bleeding, in particular, have arisen debates on its use for the primary prevention of MI. The present research evaluates the cost-effectiveness of the use of aspirin in the primary prevention of MI among Iranian men with average cardiovascular disease (CVD) risk, using Markov modeling technique. The incremental cost-effectiveness ratios (ICERs) estimated to be 864 USA dollars (USD) per quality-adjusted life years (QALY) gained and 782 USD per life years gained (LYG) for each patient in the base-case scenario (public tariffs and no discounting). This research proves cost-effectiveness of the use of aspirin in the primary prevention of MI in targeted population, since the assessed ICERs are quite under the recommended threshold by WHO which is one gross domestic product (GDP) per capita ($5315.1 for Iran in 2015).

  17. Evaluation of (68)Ga-labeled peptide tracer for detection of gelatinase expression after myocardial infarction in rat.

    Science.gov (United States)

    Kiugel, Max; Kytö, Ville; Saanijoki, Tiina; Liljenbäck, Heidi; Metsälä, Olli; Ståhle, Mia; Tuomela, Johanna; Li, Xiang-Guo; Saukko, Pekka; Knuuti, Juhani; Roivainen, Anne; Saraste, Antti

    2016-12-02

    Matrix metalloproteinases 2 and 9 (MMP-2/9) play a role in extracellular matrix remodeling after an ischemic myocardial injury. We evaluated (68)Ga-DOTA-peptide targeting MMP-2/9 for the detection of gelatinase expression after myocardial infarction (MI) in rat. Rats were injected with 43 ± 7.7 MBq of (68)Ga-DOTA-peptide targeting MMP-2/9 at 7 days (n = 7) or 4 weeks (n = 8) after permanent coronary ligation or sham operation (n = 5 at both time points) followed by positron emission tomography (PET). The left ventricle was cut in frozen sections for autoradiography and immunohistochemistry 30 minutes after tracer injection. Immunohistochemical staining showed MMP-2 and MMP-9 expressing cells, CD31-positive endothelial cells, and CD68-positive macrophages in the infarcted myocardium. Autoradiography showed increased tracer uptake in the infarcted area both at 7 days and 4 weeks after MI (MI-to-remote area ratio 2.5 ± 0.46 and 3.1 ± 1.0, respectively). Tracer uptake in damaged tissue correlated with the amount of CD68-positive macrophages at 7 days after MI, and CD31-positive endothelial cells at 7 days and 4 weeks after MI. The tracer was rapidly metabolized, radioactivity in the blood exceeded that of the myocardium, and tracer accumulation in the heart was not detectable by in vivo PET. (68)Ga-DOTA-peptide targeting MMP-2/9 accumulates in the damaged rat myocardium after an ischemic injury, but tracer instability and slow clearance in vivo make it unsuitable for further evaluation.

  18. The Gd anisotropy in GdCo sub 5

    Energy Technology Data Exchange (ETDEWEB)

    Radwanski, R.J.; Franse, J.J.M.; Quang, P.H.; Kayzel, F.E. (Van der Waals-Zeeman Lab., Univ. van Amsterdam (Netherlands))

    1992-02-01

    High-field magnetization curves of single-crystalline GdCo{sub 5} have been measured at 4.2 K up to 35 T in order to clarify the presence of an extra Gd contribution to the magnetocrystalline anisotropy. The 3d-4f exchange interactions and the Co sublattice anisotropy have been evaluated in GdCo{sub 5} and Gd{sub 2}Fe{sub 17}. No significant Gd contribution to the anisotropy has been revealed. (orig.).

  19. In vivo evaluation of the elastic anisotropy of the human Achilles tendon using shear wave dispersion analysis

    Science.gov (United States)

    Brum, J.; Bernal, M.; Gennisson, J. L.; Tanter, M.

    2014-02-01

    Non-invasive evaluation of the Achilles tendon elastic properties may enhance diagnosis of tendon injury and the assessment of recovery treatments. Shear wave elastography has shown to be a powerful tool to estimate tissue mechanical properties. However, its applicability to quantitatively evaluate tendon stiffness is limited by the understanding of the physics on the shear wave propagation in such a complex medium. First, tendon tissue is transverse isotropic. Second, tendons are characterized by a marked stiffness in the 400 to 1300 kPa range (i.e. fast shear waves). Hence, the shear wavelengths are greater than the tendon thickness leading to guided wave propagation. Thus, to better understand shear wave propagation in tendons and consequently to properly estimate its mechanical properties, a dispersion analysis is required. In this study, shear wave velocity dispersion was measured in vivo in ten Achilles tendons parallel and perpendicular to the tendon fibre orientation. By modelling the tendon as a transverse isotropic viscoelastic plate immersed in fluid it was possible to fully describe the experimental data (deviation<1.4%). We show that parallel to fibres the shear wave velocity dispersion is not influenced by viscosity, while it is perpendicularly to fibres. Elasticity (found to be in the range from 473 to 1537 kPa) and viscosity (found to be in the range from 1.7 to 4 Pa.s) values were retrieved from the model in good agreement with reported results.

  20. Stress and rest dynamic myocardial perfusion imaging by evaluation of complete time-attenuation curves with dual-source CT.

    Science.gov (United States)

    Ho, Kheng-Thye; Chua, Kia-Chong; Klotz, Ernst; Panknin, Christoph

    2010-08-01

    This study sought to describe a protocol for myocardial perfusion imaging using dipyridamole stress, with 128-slice dual-source computed tomography (CT), and to assess the ability of CT myocardial perfusion imaging (MPI) to detect abnormal flow reserve and infarction in comparison with nuclear MPI (NMPI). CT MPI has not been previously described with the 128-slice dual-source CT scanner, or with the complete evaluation of dynamic time-attenuation curves of the myocardium. Thirty-five patients underwent a stress CT MPI protocol. Complete time-attenuation curves of the myocardium were acquired using a novel scan mode, which acquires prospectively electrocardiogram (ECG)-triggered axial images at 2 rapidly alternating positions. Myocardial blood flow (MBF) values of fixed and reversible defects obtained were compared between rest and stress. Findings on CT MPI were correlated to NMPI. Perfusion defects detected on CT were correlated to coronary stenoses detected on CT angiography (CTA) and invasive coronary angiography (ICA). There was a 1.5-fold difference between stress (1.21 +/- 0.31 cc/cc/min) and rest (0.82 +/- 0.22 cc/cc/min) MBF in normal tissue. In reversible defects, MBF was 0.65 +/- 0.21 cc/cc/min and 0.63 +/- 0.18 cc/cc/min at stress and rest, respectively. In fixed defects, the MBF was 0.57 +/- 0.22 cc/cc/min at stress and 0.54 +/- 0.23 cc/cc/min at rest. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CT MPI for identifying segments with perfusion defects was 0.83, 0.78, 0.79, and 0.82, respectively. ICA results were available for 30 patients. Sensitivity, specificity, PPV, and NPV of CT MPI compared with ICA were 0.95, 0.65, 0.78, and 0.79, respectively. The radiation dose for CT MPI was 9.15 +/- 1.32 mSv for the stress scan and 9.09 +/- 1.40 mSv for the rest scan. Vasodilator-stress CT MPI may be feasible in human subjects at a radiation dose similar to NMPI. It identifies areas of abnormal flow reserve

  1. Myocardial Calcinosis a Case Report

    Directory of Open Access Journals (Sweden)

    Naciye Özeren

    2014-07-01

    Full Text Available Myocardial calcification (myocardial calcinosis is a rare condition in the literature. Meta-static or dystrophic calcification can be seen in two types. Chronic renal failure, hemodialysis, sec-ondary hyperparathyroidism, hypercalcemia, the blood calcium level as high phenomena that are associated with metastatic calcification. In dystrophic calcification, normal blood calcium levels, normal kidney functions, normal coronary artery are observed. Myocardial calcification as a result of congestive heart failure, fatal arrhythmias, heart valve dysfunction, myocardial infarction may occur. Case: 35 years old Syrian male. In the civil war in Syria bombing injured as a result, nearly two months in various hospitals and treated for renal failure developing died. Evaluated within the scope of forensic autopsy has been decided. At autopsy; scar tissue due to previous operations, in-ternal examination in both kidneys logy was found the abse formation. Microscopy: Lobular pneu-monia, atelectasis, edema in the lung. Retroperitoneal active chronic inflammation, inflammatory exudate, bleeding, abscesses and abscess wall was detected. The coronary arteries were normal. myocardial more pericardial and myocardial tissue including tissue calcification was found in the common. Renal failure caused by a lack of calcium in blood as myocardial calcinosis was evaluat-ed. These deposits often may actually on the whole body, generally, vessels, kidneys, lungs, interstitial tissues of gastric mucosa holds. Pericardium and in myocardial tissue is extremely rare, interesting case is presented here. Key Words: Hypercalcemia, Calcification, Myocardial.

  2. Effect of inversion time on the precision of myocardial late gadolinium enhancement quantification evaluated with synthetic inversion recovery MR imaging.

    Science.gov (United States)

    Varga-Szemes, Akos; van der Geest, Rob J; Schoepf, U Joseph; Spottiswoode, Bruce S; De Cecco, Carlo N; Muscogiuri, Giuseppe; Wichmann, Julian L; Mangold, Stefanie; Fuller, Stephen R; Maurovich-Horvat, Pal; Merkely, Bela; Litwin, Sheldon E; Vliegenthart, Rozemarijn; Suranyi, Pal

    2017-08-01

    To evaluate the influence of inversion time (TI) on the precision of myocardial late gadolinium enhancement (LGE) quantification using synthetic inversion recovery (IR) imaging in patients with myocardial infarction (MI). Fifty-three patients with suspected prior MI underwent 1.5-T cardiac MRI with conventional magnitude (MagIR) and phase-sensitive IR (PSIR) LGE imaging and T1 mapping at 15 min post-contrast. T1-based synthetic MagIR and PSIR images were calculated with a TI ranging from -100 to +150 ms at 5-ms intervals relative to the optimal TI (TI0). LGE was quantified using a five standard deviation (5SD) and full width at half-maximum (FWHM) thresholds. Measurements were compared using one-way analysis of variance. The MagIRsy technique provided precise assessment of LGE area at TIs ≥ TI0, while precision was decreased below TI0. The LGE area showed significant differences at ≤ -25 ms compared to TI0 using 5SD (P T1 map-based PSIRsy images provide precise quantification of MI independent of TI at the investigated time point post-contrast. MagIRsy-based MI quantification is precise at TI0 and at longer TIs while showing decreased precision at TI values below TI0. • Synthetic IR imaging retrospectively generates LGE images at any theoretical TI • Synthetic IR imaging can simulate the effect of TI on LGE quantification • Fifteen minutes post-contrast MagIR sy accurately quantifies infarcts from TI 0 to TI 0   + 150 ms • Fifteen minutes post-contrast PSIR sy provides precise infarct size independent of TI • Synthetic IR imaging has further advantages in reducing operator dependence.

  3. Evaluation of oxidative stress and homocysteine level in patients with acute myocardial infarction: a case-control study

    Directory of Open Access Journals (Sweden)

    Masume Boomi Ghuchane Atigh

    2016-05-01

    Full Text Available Background and Aim: Along with the development of cardiac diagnostic procedures, new risk factors ,such as homocysteine role in cardiovascular disease, have been proposed. The aim of the present study was to evaluate the levels of homocysteine and total antioxidant capacity in patients with acute myocardial infarction compared with the control group. Materials and Methods: A case-control study was conducted on 45 patients with myocardial infarction admitted to Vali-e-asr hospital in Birjand and 45 healthy people matched with the case group.Total antioxidant capacity applying FRAP method and homocysteine levels were measured using ELISA The obtained data was analyzed by means of SPSS software at the significant level P <0.05. Results: There was no statistically significant difference in terms of age, sex, body mass index, lipid profile and fasting blood glucose between two groups. Total antioxidant capacity in case and control groups, respectively 837.86±175.07 and 981.91±276.57 µmol/L and average level of homocysteine in the case and control groups, 15.77±8.09 and 12.19±6.75 respectively.Statistical analysis showed that the antioxidant capacity in the patient group was significantly lower than the control group (P=0.004 and no significant difference in the levels of homocysteine in both groups (P = 0.11. Conclusion: The study showed that oxidative stress and low antioxidant capacity can be associated with the pathogenesis of MI; and more studies are required to confirm the relationship between homocysteine and cardiovascular disease.

  4. Effect of inversion time on the precision of myocardial late gadolinium enhancement quantification evaluated with synthetic inversion recovery MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Varga-Szemes, Akos; Schoepf, U.J.; De Cecco, Carlo N.; Fuller, Stephen R.; Suranyi, Pal [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Geest, Rob J. van der [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Spottiswoode, Bruce S. [Siemens Medical Solutions, Chicago, IL (United States); Muscogiuri, Giuseppe [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Bambino Gesu Children' s Hospital IRCCS, Department of Imaging, Rome (Italy); Wichmann, Julian L. [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt (Germany); Mangold, Stefanie [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); Eberhard-Karls University Tuebingen, Department of Diagnostic and Interventional Radiology, Tuebingen (Germany); Maurovich-Horvat, Pal; Merkely, Bela [Semmelweis University, MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Budapest (Hungary); Litwin, Sheldon E. [Medical University of South Carolina, Division of Cardiology, Department of Medicine, Charleston, SC (United States); Vliegenthart, Rozemarijn [Medical University of South Carolina, Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Charleston, SC (United States); University of Groningen, University Medical Center Groningen, Center for Medical Imaging-North East Netherlands, Department of Radiology, Groningen (Netherlands)

    2017-08-15

    To evaluate the influence of inversion time (TI) on the precision of myocardial late gadolinium enhancement (LGE) quantification using synthetic inversion recovery (IR) imaging in patients with myocardial infarction (MI). Fifty-three patients with suspected prior MI underwent 1.5-T cardiac MRI with conventional magnitude (MagIR) and phase-sensitive IR (PSIR) LGE imaging and T1 mapping at 15 min post-contrast. T1-based synthetic MagIR and PSIR images were calculated with a TI ranging from -100 to +150 ms at 5-ms intervals relative to the optimal TI (TI{sub 0}). LGE was quantified using a five standard deviation (5SD) and full width at half-maximum (FWHM) thresholds. Measurements were compared using one-way analysis of variance. The MagIR{sub sy} technique provided precise assessment of LGE area at TIs ≥ TI{sub 0}, while precision was decreased below TI{sub 0}. The LGE area showed significant differences at ≤ -25 ms compared to TI{sub 0} using 5SD (P < 0.001) and at ≤ -65 ms using the FWHM approach (P < 0.001). LGE measurements did not show significant difference over the analysed TI range in the PSIR{sub sy} images using either of the quantification methods. T1 map-based PSIR{sub sy} images provide precise quantification of MI independent of TI at the investigated time point post-contrast. MagIR{sub sy}-based MI quantification is precise at TI{sub 0} and at longer TIs while showing decreased precision at TI values below TI{sub 0}. (orig.)

  5. Influence of revascularization on myocardial perfusion, metabolism and function evaluated with I-123-IPPA

    Energy Technology Data Exchange (ETDEWEB)

    Kropp, J.; Krois, M.; Eichhorn, B.; Feske, W.; Likungu, J.; Kirchhoff, P.J.; Luederitz, B.; Biersack, H.J. [Bonn Univ. (Germany); Knapp, F.F. Jr. [Oak Ridge National Lab., TN (United States)

    1993-10-01

    Patients with coronary artery disease (CAD) were investigated with sequential SPECT-scintigraphy after administration of 200 MBq of 15-(p-[I-123]iodophenyl)pentadecanoic acid (IPPA) at peak submaximal exercise. Twenty patients underwent coronary angioplasty (PTCA) from which 14 had control coronary arteriography (CA) and left ventricular cineventriculography (LVCV). Nineteen pts underwent bypass graft surgery (ACB) and stress sonagraphy. Semi-quantification of uptake (Up related to perfusion) and turnover (Tr) was obtained by segmental comparison of oblique slices. About 90% of the reperfused myocardial segments in the PTCA-group and 76% in the ACB-group showed an improvement of uptake after therapy (RUp). Of these, 50% and 66% exhibited increased turnover (RTr) after PTCA or ACB. Pathologic RTr was highly correlated with regional wall motion abnormalities after therapy in both groups. In the ACB-group presence of improvement of RTr was correlated with improved RWM at rest and stress. IPPA-studies show potential to provide information about changes of perfusion and metabolism after reperfusion and IPPA-turnover is a good predictor of the pattern of contractile function.

  6. Synthesis and bio-evaluation of a new fatty acid derivative for myocardial imaging.

    Science.gov (United States)

    Mathur, Anupam; Subramanian, Suresh; Mallia, Madhava B; Banerjee, Sharmila; Samuel, Grace; Sarma, Haladhar D; Venkatesh, Meera

    2008-09-01

    Development of a (99m)Tc-fatty acid analogue is of interest, as (99m)Tc is logistically advantageous over the cyclotron-produced (11)C and (123)I. Synthesis of a 16 carbon fatty acid derivative and its radiolabeling with the novel [(99m)TcN(PNP)](2+) core is described here. Hexadecanedioic acid was conjugated to cysteine in an overall yield of 55%. This ligand could be labeled with (99m)Tc via the [(99m)TcN(PNP)](2+) core, in 80% yield, as a mixture of two isomers (syn and anti). The major isomer isolated by HPLC was used for bioevaluation studies in swiss mice and compared with radioiodinated iodophenyl pentadecanoic acid (IPPA), an established agent for myocardial metabolic imaging. (99m)Tc-labeled complex cleared faster from the non-target organs, namely, liver, lungs, and blood compared to that of [(125)I]-IPPA. However, the complex exhibited lower uptake and faster washout from the myocardium as compared to [(125)I]-IPPA.

  7. Assessment of myocardial changes in athletes with native T1 mapping and cardiac functional evaluation using 3 T MRI.

    Science.gov (United States)

    Görmeli, Cemile Ayşe; Görmeli, Gökay; Yağmur, Jülide; Özdemir, Zeynep Maraş; Kahraman, Ayşegül Sağır; Çolak, Cemil; Özdemir, Ramazan

    2016-06-01

    Intensive physical exercise leads to increases in left ventricular muscle mass and wall thickness. Cardiac magnetic resonance imaging allows the assessment of functional and morphological changes in an athlete's heart. In addition, a native T1 mapping technique has been suggested as a non-contrast method to detect myocardial fibrosis. The aim of this study was to show the correlation between athletes' cardiac modifications and myocardial fibrosis with a native T1 mapping technique. A total of 41 healthy non-athletic control subjects and 46 athletes underwent CMR imaging. After the functional and morphological assessments, native T1 mapping was performed in all subjects using 3.0 T magnetic resonance imaging. Most of the CMR findings were significantly higher in athletes who had ≥5 years of sports activity when compared with non-athletic controls and athletes who had T1 values in athletes who had T1 mapping technique has the potential to discriminate myocardial fibrotic changes in athletes when compared to a normal myocardium. The T1 mapping method might be a feasible technique to evaluate athletes because it does not involve contrast, is non-invasive and allows for easy evaluation of myocardial remodeling.

  8. The need for standardisation of cardiac FDG PET imaging in the evaluation of myocardial viability in patients with chronic ischaemic left ventricular dysfunction

    Energy Technology Data Exchange (ETDEWEB)

    Kuuti, J. [Turku Univ. (Finland). Turku PET Centre; Schelbert, H.R. [UCLA School of Medicine, Los Angeles, CA (United States). Dept. of Molecular and Medical Pharmacology; Bax, J.J. [Leiden University Medical Center (Netherlands). Dept. of Cardilogy

    2002-09-01

    The evaluation of myocardial glucose utilisation with fluorine-18 fluorodeoxyglucose (FDG) and positron emission tomography is currently considered the most reliable tool for the identification of myocardial viability. However, the investigations using FDG imaging to predict improvement in left ventricular (LV) function after revascularisation have reported wide ranges for sensitivity (71%-100%) and, in particular, for specificity (33%-91%). The variable results may be related to differences in study populations but also to differences in the imaging protocols employed. Detailed analysis of the published studies has revealed differences in study populations, patient selection criteria, the methods for assessing changes in LV function post revascularisation and the timing of these assessments. Even more importantly, protocols have varied substantially with regard to imaging equipment, perfusion tracers, metabolic conditions, data analysis and interpretation of results. In addition, evaluation of patients with insulin resistance appears to represent a specific challenge. This review examines the different study protocols and methodologies used for myocardial FDG imaging in order to draw conclusions concerning optimal imaging protocols. It appears that the optimisation and standardisation of study protocols and analysis of FDG images for the assessment of myocardial viability are critical. In addition, multi-centre trials seem warranted on prediction of long-term function, congestive heart failure symptoms, survival and quality of life.

  9. Evaluation of ECG-gated [(11)C]acetate PET for measuring left ventricular volumes, mass, and myocardial external efficiency.

    Science.gov (United States)

    Hansson, Nils Henrik; Tolbod, Lars; Harms, Johannes; Wiggers, Henrik; Kim, Won Yong; Hansen, Esben; Zaremba, Tomas; Frøkiær, Jørgen; Jakobsen, Steen; Sørensen, Jens

    2016-08-01

    Noninvasive estimation of myocardial external efficiency (MEE) requires measurements of left ventricular (LV) oxygen consumption with [(11)C]acetate PET in addition to LV stroke volume and mass with cardiovascular magnetic resonance (CMR). Measuring LV geometry directly from ECG-gated [(11)C]acetate PET might enable MEE evaluation from a single PET scan. Therefore, we sought to establish the accuracy of measuring LV volumes, mass, and MEE directly from ECG-gated [(11)C]acetate PET. Thirty-five subjects with aortic valve stenosis underwent ECG-gated [(11)C]acetate PET and CMR. List mode PET data were rebinned into 16-bin ECG-gated uptake images before measuring LV volumes and mass using commercial software and compared to CMR. Dynamic datasets were used for calculation of mean LV oxygen consumption and MEE. LV mass, volumes, and ejection fraction measured by CMR and PET correlated strongly (r = 0.86-0.92, P PET (P PET-based MEE, corrected for bias, correlated fairly with PET/CMR-based MEE (r = 0.60, P PET-based MEE bias was strongly associated with LV wall thickness. Although analysis-related improvements in accuracy are recommended, LV geometry estimated from ECG-gated [(11)C]acetate PET correlate excellently with CMR and can indeed be used to evaluate MEE.

  10. Elastic Anisotropy of Basalt

    Science.gov (United States)

    Becker, K.; Shapiro, S.; Stanchits, S.; Dresen, G.; Kaselow, A.; Vinciguerra, S.

    2005-12-01

    Elastic properties of rocks are sensitive to changes of the in-situ stress and damage state. In particular, seismic velocities are strongly affected by stress-induced formation and deformation of cracks or shear-enhanced pore collapse. The effect of stress on seismic velocities as a result of pore space deformation in isotropic rock at isostatic compression may be expressed by the equation: A+K*P-B*exp (-D*P) (1), where P=Pc-Pp is the effective pressure, the pure difference between confining pressure and pore pressure. The parameter A, K, B and D describe material constants determined using experimental data. The physical meaning of the parameters is given by Shapiro (2003, in Geophysics Vol.68(Nr.2)). Parameter D is related to the stress sensitivity of the rock. A similar relation was derived by Shapiro and Kaselow (2005, in Geophysics in press) for weak anisotropic rocks under arbitrary load. They describe the stress dependent anisotropy in terms of Thomson's (1986, in Geophysics, Vol. 51(Nr.10)) anisotropy parameters ɛ and γ as a function of stress in the case of an initially isotropic rock: ɛ ∝ E2-E3, γ ∝ E3-E2 (2) with Ei=exp (D*Pi). The exponential terms Ei are controlled by the effective stress components Pi. To test this relation, we have conducted a series of triaxial compression tests on dry samples of initially isotropic Etnean Basalt in a servo-controlled MTS loading frame equipped with a pressure cell. Confining pressure was 60, 40 and 20 MPa. Samples were 5 cm in diameter and 10 cm in length. Elastic anisotropy was induced by axial compression of the samples through opening and growth of microcracks predominantly oriented parallel to the sample axis. Ultrasonic P- and S- wave velocities were monitored parallel and normal to the sample axis by an array of 20 piezoceramic transducers glued to the surface. Preamplified full waveform signals were stored in two 12 channel transient recorders. According to equation 2 the anisotropy parameters are

  11. Evaluation of heart perfusion in patients with acute myocardial infarction using dynamic contrast-enhanced magnetic resonance imaging

    DEFF Research Database (Denmark)

    Nielsen, Gitte; Hansen, Thomas Fritz; Dirks, Christina G

    2004-01-01

    with acute transmural myocardial infarction were studied using a Turbo-fast low angle shot (FLASH) MRI sequence to monitor the first pass of an extravascular contrast agent (CA), gadolinium diethylene triamine pentaacetic acid (Gd-DTPA). Quantitation of perfusion, expressed as Ki (mL/100 g/minute), in five...... acutely ill patients following acute myocardial infarction. The technique provides information on both the volume and severity of affected myocardial tissue, enabling the power of treatment regimes to be assessed objectively, and this approach should aid individual patient stratification and prognosis...

  12. Evaluation of heart perfusion in patients with acute myocardial infarction using dynamic contrast-enhanced magnetic resonance imaging

    DEFF Research Database (Denmark)

    Nielsen, Gitte; Fritz-Hansen, Thomas; Dirks, Christina G

    2004-01-01

    acutely ill patients following acute myocardial infarction. The technique provides information on both the volume and severity of affected myocardial tissue, enabling the power of treatment regimes to be assessed objectively, and this approach should aid individual patient stratification and prognosis...... with acute transmural myocardial infarction were studied using a Turbo-fast low angle shot (FLASH) MRI sequence to monitor the first pass of an extravascular contrast agent (CA), gadolinium diethylene triamine pentaacetic acid (Gd-DTPA). Quantitation of perfusion, expressed as Ki (mL/100 g/minute), in five...

  13. Cosmic Microwave Background Anisotropies

    OpenAIRE

    Hu, Wayne; Dodelson,Scott

    2001-01-01

    Cosmic microwave background (CMB) temperature anisotropies have and will continue to revolutionize our understanding of cosmology. The recent discovery of the previously predicted acoustic peaks in the power spectrum has established a working cosmological model: a critical density universe consisting of mainly dark matter and dark energy, which formed its structure through gravitational instability from quantum fluctuations during an inflationary epoch. Future observations should test this mo...

  14. Spintronic magnetic anisotropy

    OpenAIRE

    Misiorny, Maciej; Hell, Michael; Wegewijs, Maarten R.

    2014-01-01

    An attractive feature of magnetic adatoms and molecules for nanoscale applications is their superparamagnetism, the preferred alignment of their spin along an easy axis preventing undesired spin reversal. The underlying magnetic anisotropy barrier --a quadrupolar energy splitting-- is internally generated by spin-orbit interaction and can nowadays be probed by electronic transport. Here we predict that in a much broader class of quantum-dot systems with spin larger than one-half, superparamag...

  15. Measuring myocardial perfusion

    DEFF Research Database (Denmark)

    Qayyum, A A; Kastrup, J

    2015-01-01

    Recently, focus has changed from anatomical assessment of coronary arteries towards functional testing to evaluate the effect of stenosis on the myocardium before intervention. Besides positron-emission tomography (PET), cardiac MRI (CMR), and cardiac CT are able to measure myocardial perfusion......-known and is used in routine clinical practice. However, PET uses radioactive tracers and has a lower spatial resolution compared to CMR and CT. CMR and CT are emerging techniques in the field of myocardial perfusion imaging. CMR uses magnetic resonance to obtain images, whereas CT uses x-rays during first...

  16. Evaluation of ¹⁸F-labeled BODIPY dye as potential PET agents for myocardial perfusion imaging.

    Science.gov (United States)

    Liu, Shuanglong; Li, Dan; Shan, Hong; Gabbaï, Francois P; Li, Zibo; Conti, Peter S

    2014-01-01

    Despite the great potential of positron emission tomography/computed tomography (PET/CT) in cardiovascular disease imaging, one of the major limitations is the availability of PET probes with desirable half-lives and reasonable cost. In this report, we hypothesized that lipophilic cationic BODIPY dye could be selectively accumulated in cardiac muscle, possibly for the development of novel PET myocardial perfusion imaging (MPI) probes. A (18)F-labeled BODIPY dye ([(18)F]1) was synthesized efficiently through a fluoride exchange reaction catalyzed by the Lewis acid tin chloride (SnCl₄). The compound was first evaluated by a cellular uptake assay in vitro, followed by biodistribution and microPET imaging studies in vivo. [(18)F]1 was obtained in more than 90% labeling yield, with >98% radiochemical purity. The HEK-293 cellular uptake assay showed that the preferential uptake of [(18)F]1 could be related to the cell membrane potential. The biodistribution data demonstrated high levels of [(18)F]1 accumulation in the heart. In the biodistribution study in mice, the radioactivity uptake in the heart, blood, liver and lung was 3.01 ± 0.44, 0.39 ± 0.09, 0.69 ± 0.07, 1.71 ± 0.27%ID/g, respectively, at 3h post-injection (p.i.). The heart-to-lung and heart-to-liver ratios are 1.76 ± 0.14 and 4.37 ± 0.51 at 3h p.i., respectively. Volume-of-interest analysis of the microPET images correlated well with the biodistribution studies in mice. The heart was clearly visualized in normal rats, with 0.72 ± 0.18, 0.69 ± 0.18, 0.67 ± 0.20 and 0.59 ± 0.17%ID/g uptake at 0.5, 1, 2 and 4h p.i., respectively. (18)F-labeled BODIPY dye showed good heart uptake and heart-to-blood and heart-to-lung contrast. A (18)F-labeled BODIPY dyes may represent a new category of cationic PET agents for myocardial perfusion imaging. © 2013.

  17. Synthesis and biological evaluation of cyclic analogs of L-carnitine as potential agents in the treatment of myocardial ischemia

    Energy Technology Data Exchange (ETDEWEB)

    Woster, P.M.

    1987-01-01

    The purpose of this research was to synthesize a number of cyclic, rigid analogs of L-carnitine, having a variety of predetermined positional and stereochemical orientations, to be used as probes into the spatial and conformational requirements of the enzyme known as carnitine/acylcarnitine translocase. The ability of these analogs to serve as substrates for this enzyme was to be determined by assessing the degree to which they initiate efflux of {sup 14}C-L-carnitine from isolated heart mitochondria. Toward this end, synthesis of several such analogs was attempted, resulting in the isolation and characterization of 9 cyclic analogs of carnitine, 5 of which are previously unreported. Bioevaluation of these synthetic carnitine analogs was conducted in a previously described assay system. Rat heart mitochondria were isolated by differential centrifugation and prepared for the study by incubation with {sup 14}C-L-carnitine. Efflux of radiolabeled carnitine was then monitored in the presence of the compound being evaluated. This represents the first instance in which non-naturally occurring analogs of L-carnitine have been shown to undergo transport via this mitochondrial translocase, suggesting the possibility that cyclic carnitine analogs may find utility as agents in the treatment of myocardial ischemia.

  18. Relative predictive value of lung cancer screening CT versus myocardial perfusion attenuation correction CT in the evaluation of coronary calcium.

    Science.gov (United States)

    Bailey, Grant; Healy, Abigail; Young, Bryan D; Sharma, Esseim; Meadows, Judith; Chun, Hyung J; Wu, Wen-Chih; Choudhary, Gaurav; Morrison, Alan R

    2017-01-01

    Coronary artery calcium scores (CACS) from lung cancer screening computed tomography (LCSCT) or myocardial perfusion attenuation correction computed tomography (ACCT) are not routinely performed or reported. CACS from LCSCT and ACCT have not been directly compared in the same patient population. We identified 66 patients who underwent both LCSCT (non-gated) and ECG-gated cardiac CT (CCT) within a 2-year span. Of this population, 40 subjects had also undergone ACCT. Using the Agatston method, CACS for 264 individual vessels from the LCSCT population and for 160 vessels from ACCT population were calculated and evaluated for agreement with ECG-gated CCT as the gold standard. Secondary analysis included a comparison of individual vessel contribution to variations in agreement and a comparison of total CACS from CCT, LCSCT, and ACCT for respective MACE prediction. CACS from LCSCT demonstrated a strong Pearson correlation, r = 0.9017 (0.876-0.9223), with good agreement when compared to CACS from CCT. CACS from ACCT demonstrated a significantly (P calcium scoring by providing better agreement and comparable risk assessment to CCT despite the absence of ECG-gating. It is therefore reasonable to use LCSCT images to derive and report Agatston-based CACS for cardiovascular risk assessment, whereas the use of ACCT images to report Agatston-based CACS is not currently practical.

  19. Myocardial susceptibility to ischaemia/reperfusion in obesity: a re-evaluation of the effects of age.

    Science.gov (United States)

    Webster, I; Salie, R; Marais, E; Fan, W-J; Maarman, G; Huisamen, B; Lochner, A

    2017-03-17

    Reports on the effect of age and obesity on myocardial ischaemia/reperfusion (I/R) injury and ischaemic preconditioning are contradictory. The aim of this study was to re-evaluate the effects of age and diet-induced obesity (DIO) on myocardial I/R injury and preconditioning potential. Four groups of Wistar male rats were used: age-matched controls (AMC) receiving standard rat chow for (i) 16 weeks and (ii) 16 months respectively; DIO rats receiving a sucrose-supplemented diet for (iii) 16 weeks and (iv) 16 months respectively. The ages of groups (i) and (iii) were 22 weeks ("young") and groups (ii) and (iv) 17 months ("middle-aged") at time of experimentation. Isolated perfused working hearts were subjected to 35 min regional ischaemia/1 h reperfusion. Endpoints were infarct size (tetrazolium staining) and functional recovery. Hearts were preconditioned by 3 × 5 min ischaemia/5 min reperfusion. Results were processed using GraphPad Prism statistical software. Age did not affect baseline heart function before induction of ischaemia and I/R damage as indicated by infarct size and similar values were obtained in hearts from both age groups. Age also had no effect on functional recovery of hearts during reperfusion after regional ischaemia in AMC rats, but cardiac output during reperfusion was better in hearts from middle-aged than young DIO rats. The diet reduced infarct size in hearts from young rats (% of area at risk: AMC: 32.4 ± 3.6; DIO: 20.7 ± 2.9, p < 0.05), with no differences in hearts from middle-aged rats (AMC: 24.6 ± 4.6; DIO: 28.3 ± 13.5, p = NS). Compared to their respective AMC, diet-induced obesity had no significant effect on functional recovery of hearts from both age groups after exposure to regional ischaemia. When exposed to the more severe stress of global ischaemia, the functional recovery potential of middle-aged DIO rats appeared to be impeded compared to hearts of young DIO rats, while age had no effect

  20. Dual isotope simultaneous imaging to evaluate the effects of intracoronary bone marrow-derived mesenchymal stem cells on perfusion and metabolism in canines with acute myocardial infarction

    OpenAIRE

    HAO, LINJUN; Hao, Jin; Fang, Wei; Han, Chunlei; ZHANG, KAIXIU; Wang, Xuemei

    2015-01-01

    Stem cell therapy on acute myocardial infarction (AMI) has been performed for over a decade. In the present study, cardiac perfusion, metabolism and function in dogs with AMI treated by intracoronary injection of bone marrow-derived mesenchymal stem cells (MSCs) were evaluated by dual isotope simultaneous acquisition (DISA) of single positron emission computed tomography (SPECT). Dogs (n=12, 20–30 kg) were randomly assigned to two groups: A graft study (n=6) and control group (n=6). Bone marr...

  1. Quantitative evaluation of myocardial stress/rest 201TL SPECT: results of a ROI-based method in 108 patients with CHD.

    Science.gov (United States)

    Buell, U; Stirner, H; vom Dahl, J; Uebis, R; Kleinhans, E; Biedermann, M; Grosse, W; Simon, H J

    1987-12-01

    ROI-based polar maps (33 ROIs) were employed to evaluate quantitatively stress/rest myocardial 201Tl SPECT in 108 patients with angiographically proven coronary heart disease (CHD) in comparison with 30 controls. Sensitivity in detecting a CHD with stenoses of greater than 50% of luminal diameter was determined versus normal regional values (+/- 2.5 SD) employing vitality (VI) and wash-out corrected redistribution (RD). The method was evaluated referring to the severity of the disease, to the number of ROIs displaying changes [(a) 1 ROI, (b) greater than 2 ROIs], to validity of VI, RD or a combination thereof, and for specificity. Wash-out values were found to depend on degree of stress individually achieved and thus were not used as a threshold criterion. Sensitivity in supply areas with old myocardial infarctions was 95% (a) and 86% (b), resp. With no infarction, it was 96% (a) and 79% (b), resp. VI in stenosis greater than 75% was more sensitive than RD. However, combined evaluation of VI and RD yielded sensitivities from 91-100% (a) and 77-94% (b), resp. for different main supply areas. In stenosis less than 50% with normal VI, RD was positive in 18-31%. Specificity turned out to be 91% (a) and 97% (b), resp. We conclude that the method presented is reliable to quantify numerically 201Tl kinetics in myocardial SPECT, aimed at detecting and describing CHD.

  2. {sup 123}I-meta-iodo-benzyl-guanidine myocardial scintigraphy in heart disease;Evaluation de l'innervation sympathique cardiaque par la scintigraphie myocardique a la {sup 123}I-metaiodobenzylguanidine

    Energy Technology Data Exchange (ETDEWEB)

    Valli, N. [Polyclinique de Bordeaux-Nord-Aquitaine, Service de medecine nucleaire, 33 - Bordeaux (France)

    2010-03-15

    Meta-iodo-benzyl-guanidine-iodine 123 ({sup 123}I-Mibg) myocardial scintigraphy is one of the few methods available for the objective evaluation of cardiac sympathetic function at the clinical level. Disorders of cardiac sympathetic function play an important role in a variety of heart diseases and particularly in heart failure. Mibg myocardial scintigraphy provides abundance of useful information for evaluation of severity therapeutic effects and prognosis. (author)

  3. Prospective evaluation of the use of the thrombolysis in myocardial infarction score as a risk stratification tool for chest pain patients admitted to an ED observation unit.

    Science.gov (United States)

    Holly, Jessica; Fuller, Matthew; Hamilton, David; Mallin, Michael; Black, Kathryn; Robbins, Riann; Davis, Virgil; Madsen, Troy

    2013-01-01

    The Thrombolysis in Myocardial Infarction (TIMI) score has shown use in predicting 30-day and 1-year outcomes in emergency department (ED) patients with potential acute coronary syndrome. Few studies have evaluated the TIMI score in risk stratifying patients selected for the ED observation Unit (EDOU). Risk stratification of patients in this group could identify those at risk for significant cardiac events. Our goal was to evaluate TIMI use for risk stratification in this population and compare outcomes among differing scores. A prospective observational study with 30-day telephone follow-up for a 12 month period. Baseline data, outcomes related to EDOU stay, admission, and 30-day outcomes were recorded. TIMI scores were calculated for each patient placed in EDOU. TIMI score was not utilized in the decision to place patients in observation. N = 552. Composite outcomes recorded were myocardial infarction, revascularization, or death either during the EDOU stay, inpatient admission, or the 30-day follow-up. Eighteen composite outcomes were recorded: stent (12 patients), coronary artery bypass graft (3 patients), myocardial infarction and stent (2 patients), and myocardial infarction, and coronary artery bypass graft (1 patient). Distribution by TIMI score was: 0 (102 patients), 1 (196), 2 (142), 3 (72), 4 (27), and 5 (5). Risk of composite outcome increased by score: 0 (1%), 1 (2.6%), 2 (2.1%), 3 (6.9%), 4 (11.1%), and 5 (20%). Those with an intermediate risk score (3-5) were also more likely to require admission (15.4% vs 9.8%, P = .048). The TIMI risk score may serve as an effective risk stratification tool among chest pain patients selected for EDOU placement. Patients with intermediate-risk by TIMI may be considered for inpatient admission and/or more aggressive evaluation and therapy. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Myocardial Fibrosis in Congenital Heart Disease.

    Science.gov (United States)

    Rathod, Rahul H; Powell, Andrew J; Geva, Tal

    2016-05-25

    Myocardial fibrosis is common in patients with congenital heart disease (CHD) and has been associated with arrhythmias, decreased functional status, and adverse ventricular mechanics. There are multiple types of myocardial fibrosis that occur in response to different pathophysiologic stimuli. Recent advances in imaging technology have made detection and quantification of the types of myocardial fibrosis possible. In this review, we describe the pathophysiology of myocardial fibrosis, examine the imaging techniques used to evaluate fibrosis, and discuss the relationship between myocardial fibrosis and clinical outcomes in CHD. (Circ J 2016; 80: 1300-1307).

  5. Non-Gaussianity and the Cosmic Microwave Background Anisotropies

    CERN Document Server

    Bartolo, N; Riotto, A

    2010-01-01

    We review in a pedagogical way the present status of the impact of non-Gaussianity (NG) on the Cosmic Microwave Background (CMB) anisotropies. We first show how to set the initial conditions at second-order for the (gauge invariant) CMB anisotropies when some primordial NG is present. However, there are many sources of NG in CMB anisotropies, beyond the primordial one, which can contaminate the primordial signal. We mainly focus on the NG generated from the post-inflationary evolution of the CMB anisotropies at second-order in perturbation theory at large and small angular scales, such as the ones generated at the recombination epoch. We show how to derive the equations to study the second-order CMB anisotropies and provide analytical computations to evaluate their contamination to primordial NG (complemented with numerical examples). We also offer a brief summary of other secondary effects. This review requires basic knowledge of the theory of cosmological perturbations at the linear level.

  6. Flow stress anisotropy

    DEFF Research Database (Denmark)

    Winther, G.

    1996-01-01

    stress Variation in the rolling plane, which may be as high as 20%, are presented. The traditional Taylor model is applied to the data to account for the effect of texture. However, texture effects alone are not enough to explain all of the observed anisotropy. New models which take the combined effects...... of texture and deformation microstructure into account are presented. The models are based on the Taylor and Sachs models but modified with an anisotropic critical shear stress to account for the effect of the microstructure. The agreement between experimental data and model predictions is definitely better...

  7. Preliminary evaluation of treatment efficacy of umbilical cord blood-derived mesenchymal stem cell-differentiated cardiac pro-genitor cells in a myocardial injury mouse model

    Directory of Open Access Journals (Sweden)

    Truc Le-Buu Pham

    2015-12-01

    Full Text Available Recently, stem cell therapy has been investigated as a strategy to prevent or reverse damage to heart tissue. Although the results of cell transplantation in animal models and patients with myocardial ischemia are promising, the selection of the appropriate cell type remains an issue that requires consideration. In this study, we aimed to evaluate the effect of cardiac progenitor cell transplantation in a mouse model of myocardial ischemia. The cardiac progenitor cells used for transplantation were differentiated from umbilical cord blood mesenchymal stem cells. Animal models injected with phosphate-buffered saline (PBS and healthy mice were used as controls. Cell grafting was assessed by changes in blood pressure and histological evaluation. After 14 days of transplantation, the results demonstrated that the blood pressure of transplanted mice was stable, similar to healthy mice, whereas it fluctuated in PBS-injected mice. Histological analysis showed that heart tissue had regenerated in transplanted mice, but remained damaged in PBS-injected mice. Furthermore, trichrome staining revealed that the transplanted mice did not generate significant amount of scar tissue compared with PBS-injected control mice. In addition, the cardiac progenitor cells managed to survive and integrate with local cells in cell-injected heart tissue 14 days after transplantation. Most importantly, the transplanted cells did not exhibit tumorigenesis. In conclusion, cardiac progenitor cell transplantation produced a positive effect in a mouse model of myocardial ischemia. [Biomed Res Ther 2015; 2(12.000: 435-445

  8. Relationship between myocardial T2* values and cardiac volumetric and functional parameters in β-thalassemia patients evaluated by cardiac magnetic resonance in association with serum ferritin levels

    Energy Technology Data Exchange (ETDEWEB)

    Liguori, Carlo, E-mail: c.liguori@unicampus.it [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Pitocco, Francesca, E-mail: f.pitocco@unicampus.it [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Di Giampietro, Ilenia, E-mail: i.digiampietro@unicampus.it [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Vivo, Aldo Eros de, E-mail: devivoeros@gmail.com [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Schena, Emiliano, E-mail: e.schena@unicampus.it [Unit of Measurements and Biomedical Instrumentation, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy); Cianciulli, Paolo, E-mail: CIANCIULLI.PAOLO@aslrmc.it [Thalassemia Unit, Ospedale Sant Eugenio, Piazzale dell’Umanesimo 10, 00143 Rome (Italy); Zobel, Bruno Beomonte, E-mail: b.zobel@unicampus.it [Department of Diagnostic Imaging, Campus Bio Medico University, via Alvaro del Portillo 200, 00128 Rome (Italy)

    2013-09-15

    Purpose: Myocardial T2* cardiovascular magnetic resonance provides a rapid and reproducible assessment of cardiac iron load in thalassemia patients. Although cardiac involvement is mainly characterized by left ventricular dysfunction caused by iron overload, little is known about right ventricular function. The aim of this study was to assess the relationship between T2* value in myocardium and left–right ventricular volumetric and functional parameters and to evaluate the existing associations between left–right ventricles volumetric and functional parameter, myocardial T2* values and blood ferritin levels. Materials and methods: A retrospective analysis of 208 patients with β-thalassemia major and thalassemia intermedia was performed (109 males and 99 females; mean age 37.7 ± 13 years; 143 thalassemia major, 65 thalassemia intermedia). Myocardial iron load was assessed by T2* measurements, and volumetric functions were analyzed using the steady state free precession sequence. Results: A significant correlation was observed between EFLV and T2* (p = 0.0001), EFRV and T2* (p = 0.0279). An inverse correlation was present between DVLV and T2* (p = 0.0468), SVLV and T2* (p = 0.0003), SVRV and T2* (p = 0.0001). There was no significant correlation between cardiac T2* and LV–RV mass indices. A significant correlation was observed between T2* and serum ferritin levels (p < 0.001) and between EFLV and serum ferritin (p < 0.05). Conclusion: Myocardial iron load assessed by T2* cardiac magnetic resonance is associated with deterioration in left–right ventricular function; this is more evident when T2* values fall below 14 ms. CMR appears to be a promising approach for cardiac risk evaluation in TM patients.

  9. Microstructure, Slip Systems and Yield Stress Anisotropy in Plastic Deformation

    DEFF Research Database (Denmark)

    Winther, Grethe; You, Ze Sheng; Lu, Lei

    The highly anisotropic microstructures in nanotwinned copper produced by electrodeposition provide an excellent opportunity to evaluate models for microstructurally induced mechanical anisotropy. A crystal plasticity model originally developed for the integration of deformation induced dislocation...

  10. Magnetic anisotropy in nanostructures

    CERN Document Server

    Eisenbach, M

    2001-01-01

    method for solving the LDA Kohn-Sham equation. This extended code allows us to perform fully relativistic calculations to enable us to investigate the spin orbit coupling effects leading to anisotropies and potentially non collinear ordering of magnetic moments in these systems of magnetic inclusions in copper. With this approach we find that depending on the orientation of the atoms along the 100 or 110 direction in copper the ground state orientation of the magnetic moments in the chain is either perpendicular or parallel to the chain direction, when the magnetic dipolar interaction energy is added to the final ab initio result. In this thesis we investigate the effect of magnetic anisotropies in nanostructured materials. The main emphasis in our work presented here is on systems that have an underlying one dimensional structure, like nanowires or atomic chains. In a simple classical one dimensional model we show the rich ground state structure of magnetic orientations one might expect to find in such syste...

  11. Systematic drug safety evaluation based on public genomic expression (Connectivity Map) data: Myocardial and infectious adverse reactions as application cases

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Kejian, E-mail: kejian.wang.bio@gmail.com [Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai (China); Weng, Zuquan [Japan National Institute of Occupational Safety and Health, Kawasaki (Japan); Sun, Liya [Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai (China); Sun, Jiazhi; Zhou, Shu-Feng [Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL (United States); He, Lin, E-mail: helin@Bio-X.com [Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Shanghai Jiao Tong University, Shanghai (China)

    2015-02-13

    Adverse drug reaction (ADR) is of great importance to both regulatory agencies and the pharmaceutical industry. Various techniques, such as quantitative structure–activity relationship (QSAR) and animal toxicology, are widely used to identify potential risks during the preclinical stage of drug development. Despite these efforts, drugs with safety liabilities can still pass through safety checkpoints and enter the market. This situation raises the concern that conventional chemical structure analysis and phenotypic screening are not sufficient to avoid all clinical adverse events. Genomic expression data following in vitro drug treatments characterize drug actions and thus have become widely used in drug repositioning. In the present study, we explored prediction of ADRs based on the drug-induced gene-expression profiles from cultured human cells in the Connectivity Map (CMap) database. The results showed that drugs inducing comparable ADRs generally lead to similar CMap expression profiles. Based on such ADR-gene expression association, we established prediction models for various ADRs, including severe myocardial and infectious events. Drugs with FDA boxed warnings of safety liability were effectively identified. We therefore suggest that drug-induced gene expression change, in combination with effective computational methods, may provide a new dimension of information to facilitate systematic drug safety evaluation. - Highlights: • Drugs causing common toxicity lead to similar in vitro gene expression changes. • We built a model to predict drug toxicity with drug-specific expression profiles. • Drugs with FDA black box warnings were effectively identified by our model. • In vitro assay can detect severe toxicity in the early stage of drug development.

  12. [Quality indicators of hospital care: evaluation of patient care in acute myocardial infarction].

    Science.gov (United States)

    Belicza, E; Balogh, A; Szócska, M

    2001-05-27

    In the international hospital accreditation programs there is an increasing emphasis on involving performance indicators. The inpatient mortality rate of AMI patients and the usage of thrombolytic therapy are very common, evidence based indicators of these programs. The authors goal was to analyze the applicability of these indicators in the evaluation of the Hungarian hospital care. In Hungary, there is a data collection system on every inpatient case. This database was used to determine the above mentioned two indicators for 1997 and 1998. They calculated by hospital group level, by institutions and by geographic areas crude rates and rates adjusted for age and gender, and for severity using the different DRGs of AMI patients. In these two years the inpatient mortality rates of AMI patients were 20.4% and 21.7%, and the usage of thrombolytic therapy were 9.9% and 11.8%, respectively. Using indirect standardization methodology in the usage of thrombolytic therapy, they found high differences among the counties compared to the national average, the range was 51-199%, and among the institutions 0-306%, respectively. It is clear, that there are huge differences in the curative processes and in the inpatient mortality rates of AMI patients among the hospitals. The differences are developed by chance, there are no close connections either to hospital groups, or to geographical locations. Because of the difficulties of risk adjustment, they suggested that indicators were suitable for benchmarking. It is necessary to implement in the national quality criteria system different indicators for evaluating the patient care, to develop programs for auditing the best and worst hospitals and to introduce standards for assuring the validity of the basic data.

  13. Geomechanics and elastic anisotropy of the Bakken Formation, Williston Basin

    Science.gov (United States)

    Ostadhassan, Mehdi

    and principal stresses of deep shales in the Williston Basin. The parameters then will be used to generate shear radial profiles and slowness-frequency plots analyze formation anisotropy type and origin as well as reservoir quality. The next step will be to evaluate direction and magnitude of the minimum and maximum anisotropic principal horizontal stresses as the governing element in geomechanical modeling. I will analyze wellbore stability and predict wellbore behavior under stress alteration caused by drilling. Elastic anisotropy of the formation will be included in the 3-D numerical models. In addition the effects of local geological features on the mode of anisotropy both in the far-field and around the borehole to get an in-depth insight of the fractures will be studied. Finally, by generating stress polygons for the reservoir, before and after production and pressure decline, I will try to study how reservoir depletion may cause future geological natural hazards such as faulting and induced seismic events in the region.

  14. Early marker of regional left ventricular deformation in patients with hypertrophic cardiomyopathy evaluated by MRI tissue tracking: The effects of myocardial hypertrophy and fibrosis.

    Science.gov (United States)

    Xu, Hua-Yan; Chen, Jing; Yang, Zhi-Gang; Li, Rui; Shi, Ke; Zhang, Qin; Liu, Xi; Xie, Lin-Jun; Jiang, Li; Guo, Ying-Kun

    2017-11-01

    To evaluate the regional left ventricular (LV) myocardial strain of early stage hypertrophic cardiomyopathy (HCM) patients by magnetic resonance (MR) tissue tracking. In all, 114 adult HCM patients classified as NYHA I or II and 32 healthy volunteers were enrolled and underwent 3.0T MR examination. Vertical 2-chamber long axis, horizontal 4-chamber, and short axis cine sequence as well as late gadolinium enhancement images (LGE) were scanned. The cardiac function, regional LV tissue tracking variables, end-diastolic wall thickness (EDTH), and LGE extent were measured. In the HCM group, 38 were NYHA I and 76 were NYHA II. By regional analysis, peak strain (PS) and peak displacement (PD) with radial, circumferential direction of hypertrophic segments (n = 283) were significantly lower than nonhypertrophic segments (n = 1541) (all P hypertrophic and fibrotic segments of early-stage HCM patients can be measured by MR tissue tracking based on routine cine images. Moreover, myocardial strain may decrease with the increasing of myocardial hypertrophy as well as fibrosis. 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2017;46:1368-1376. © 2017 International Society for Magnetic Resonance in Medicine.

  15. Synthesis and preliminary evaluation of {sup 18}F-labeled 4-thia palmitate as a PET tracer of myocardial fatty acid oxidation

    Energy Technology Data Exchange (ETDEWEB)

    DeGrado, Timothy R. E-mail: trd@petsparc.mc.duke.edu; Wang Shuyan; Holden, James E.; Nickles, R. Jerome; Taylor, Michael; Stone, Charles K

    2000-04-01

    Interest remains strong for the development of a noninvasive technique for assessment of regional fatty acid oxidation rate in the myocardium. {sup 18}F-labeled 4-thia palmitate (FTP, 16-[{sup 18}F]fluoro-4-thia-hexadecanoic acid) has been synthesized and preliminarily evaluated as a metabolically trapped probe of myocardial fatty acid oxidation for positron emission tomography (PET). The radiotracer is synthesized by Kryptofix 2.2.2/K{sub 2}CO{sub 3} assisted nucleophilic radiofluorination of an iodo-ester precursor, followed by alkaline hydrolysis and by purification by reverse phase high performance liquid chromatography. Biodistribution studies in rats showed high uptake and long retention of FTP in heart, liver, and kidneys consistent with relatively high fatty acid oxidation rates in these tissues. Inhibition of carnitine palmitoyl-transferase-I caused an 80% reduction in myocardial uptake, suggesting the dependence of trapping on the transport of tracer into the mitochondrion. Experiments with perfused rat hearts showed that the estimates of the fractional metabolic trapping rate (FR) of FTP tracked inhibition of oxidation rate of palmitate with hypoxia, whereas the FR of the 6-thia analog 17-[{sup 18}F]fluoro-6-thia-heptadecanoic acid was insensitive to hypoxia. In vivo defluorination of FTP in the rat was evidenced by bone uptake of radioactivity. A PET imaging study with FTP in normal swine showed excellent myocardial images, prolonged myocardial retention, and no bone uptake of radioactivity up to 3 h, the last finding suggesting a species dependence for defluorination of the omega-labeled fatty acid. The results support further investigation of FTP as a potential PET tracer for assessing regional fatty acid oxidation rate in the human myocardium.

  16. Usefulness of {sup 123}I-Meta-iodobenzylguanidine (MIBG) myocardial scintigraphy for evaluation of cardiac sympathetic nervous system function in diabetic patients.

    Energy Technology Data Exchange (ETDEWEB)

    Tamura, Koji; Nakatani, Yuko; Doi, Kenji; Adachi, Gakuji; Takada, Kou

    2001-11-01

    The cardiac sympathetic nervous system function of diabetic patients with no definite cardiovascular complications other than hypertension was evaluated by {sup 123}I -MIBG myocardial scintigraphy. The subjects consisted of 82 diabetic patients, 59 men, 23 women, mean age 57 years, 17 with hypertension and 65 with normal blood pressure, and they were compared with normal controls (8 men and 3 women, mean age 54 years). Myocardial scintigraphy was performed 10 minutes and 4 hours after administration of MIBG. The superior mediastinum and whole myocardium were set as regions of interest, and the heart-to-mediastinum ratio (H/M ratio) and the washout rate (%WR) were calculated. The mean observation period was 18{+-}12 months, and 17 of the 65 diabetic patients with normal blood pressure before the study developed hypertension during the observation period. There were significant differences in H/M ratio and %WR between the diabetic patients and normal controls (H/M ratio; 1.96{+-}0.34 vs 2.27{+-}0.20, %WR; 24.71{+-}16.99% vs 12.89{+-}11.94). The diabetic patients with hypertension had higher morbidity with diabetic retinopathy and a lower H/M ratio. The 17 patients who developed hypertension during the observation period showed an increase in %WR and a reduction in the H/M ratio. Five patients who died during the observation period had a reduced H/M ratio and increased of %WR. {sup 123}I-MIBG myocardial scintigraphy in diabetic patients was shown to be useful for detecting cardiac sympathetic nervous system dysfunction, predicting the development of hypertension, and identifying patients who had a poor outcome. Diabetic patients with abnormal signals on MIBG myocardial scintigraphy need to be monitored much more carefully. (K.H.)

  17. Coronary vasomotion in patients with syndrome X : Evaluation with positron emission tomography and parametric myocardial perfusion imaging

    NARCIS (Netherlands)

    Meeder, JG; Blanksma, PK; vanderWall, EE; Willemsen, ATM; Pruim, J; Anthonio, RL; deJong, RM; Vaalburg, W; Lie, KI

    The aim of this study was to elucidate further the causative mechanism of abnormal coronary vasomotion in patients with syndrome X. In patients with syndrome X, defined as angina pectoris and documented myocardial ischaemia during stress testing with normal findings at coronary angiography, abnormal

  18. Positron emission tomographic evaluation of regulation of myocardial perfusion in physiological (elite athletes) and pathological (systemic hypertension) left ventricular hypertrophy

    DEFF Research Database (Denmark)

    Kjaer, Andreas; Meyer, Christian; Wachtell, Kristian

    2005-01-01

    Myocardial perfusion (MP) may differ in physiologic and pathologic left ventricular hypertrophy (LVH). We compared MP in LVH in elite athletes and patients with hypertension with healthy, age-matched subjects. We included 12 rowers with LVH, 19 patients with hypertension with LVH, and 2 age...

  19. A model that accounts for the interdependence of extent and severity in the automatic evaluation of myocardial defects

    DEFF Research Database (Denmark)

    El-Ali, Henrik Hussein; Palmer, John; Edenbrandt, Lars

    2006-01-01

    The extent and severity are two important parameters when describing a regional defect in myocardial single-photon emission computed tomography (SPECT) perfusion imaging. Intuitively, these two parameters should be independent of each other, but we have shown in a previous study that there is an ...

  20. Daytime Thermal Anisotropy of Urban Neighbourhoods: Morphological Causation

    Directory of Open Access Journals (Sweden)

    E. Scott Krayenhoff

    2016-01-01

    Full Text Available Surface temperature is a key variable in boundary-layer meteorology and is typically acquired by remote observation of emitted thermal radiation. However, the three-dimensional structure of cities complicates matters: uneven solar heating of urban facets produces an “effective anisotropy” of surface thermal emission at the neighbourhood scale. Remotely-sensed urban surface temperature varies with sensor view angle as a consequence. The authors combine a microscale urban surface temperature model with a thermal remote sensing model to predict the effective anisotropy of simplified neighbourhood configurations. The former model provides detailed surface temperature distributions for a range of “urban” forms, and the remote sensing model computes aggregate temperatures for multiple view angles. The combined model’s ability to reproduce observed anisotropy is evaluated against measurements from a neighbourhood in Vancouver, Canada. As in previous modeling studies, anisotropy is underestimated. Addition of moderate coverages of small (sub-facet scale structure can account for much of the missing anisotropy. Subsequently, over 1900 sensitivity simulations are performed with the model combination, and the dependence of daytime effective thermal anisotropy on diurnal solar path (i.e., latitude and time of day and blunt neighbourhood form is assessed. The range of effective anisotropy, as well as the maximum difference from nadir-observed brightness temperature, peak for moderate building-height-to-spacing ratios (H/W, and scale with canyon (between-building area; dispersed high-rise urban forms generate maximum anisotropy. Maximum anisotropy increases with solar elevation and scales with shortwave irradiance. Moreover, it depends linearly on H/W for H/W < 1.25, with a slope that depends on maximum off-nadir sensor angle. Decreasing minimum brightness temperature is primarily responsible for this linear growth of maximum anisotropy. These

  1. Nuclear medicine and coronary artery disease: evaluation of tracers of myocardial perfusion and vulnerable atherosclerotic plaque; Medecine nucleaire et maladie coronarienne: evaluation de traceurs de la perfusion myocardique et de la plaque d'atherome vulnerable

    Energy Technology Data Exchange (ETDEWEB)

    Broisat, A

    2005-04-15

    Coronary artery disease is one of the primary cause of mortality worldwide. Nuclear medicine is the major imaging technique for diagnosis and following of this disease. perfusion: nowadays, major radioactive agents used in clinical practice are myocardial perfusion tracers. The reference tracer is thallium-201. However, {sup 201}Tl presents some drawbacks. {sup 99m}Tcn-noet has been proposed for its replacement. This study shows that in contrast with previous studies realized in vitro on cardio myocytes, verapamil, an l-type calcium channel inhibitor, does not inhibit myocardial fixation of {sup 99m}Tcn-noet in vivo in dog. This data is in agreement with the hypothesis of a non specific endothelial fixation of this tracer. Moreover, this study shows that as a pure tracer of myocardial perfusion, {sup 99m}Tcn-noet can also be used to assess myocardial viability on a model of myocardial chronic infarction in rat. atherosclerosis: disruption of vulnerable atherosclerotic plaques is the main event leading to coronary accidents. The second part of this study concerns the evaluation of new potential tracers of the vulnerable atherosclerotic plaque in an experimental model of rabbit with an inheritable hypercholesterolemia. The four tracers evaluated (b2702(r), b2702-I, b2702-Tc and Tc-raft-b2702) are synthetic peptides comprising the residues 75-84 of hla-b2702, a molecule known to link vcam-1, an adhesion molecule expressed in vulnerable atherosclerotic plaque. The autoradiography studies show that all tracers accumulate within atherosclerotic plaque expressing vcam- and that. i-b2702 shows the best plaque/control fixation ratio. (author)

  2. A theoretical timeline for myocardial infarction: immunohistochemical evaluation and western blot quantification for Interleukin-15 and Monocyte chemotactic protein-1 as very early markers.

    Science.gov (United States)

    Turillazzi, Emanuela; Di Paolo, Marco; Neri, Margherita; Riezzo, Irene; Fineschi, Vittorio

    2014-07-02

    Experimental and human studies have demonstrated that innate immune mechanisms and consequent inflammatory reaction play a critical role in cardiac response to ischemic injury. Thus, the detection of immuno-inflammatory and cellular phenomena accompanying cardiac alterations during the early inflammatory phase of myocardial infarction (MI) may be an excellent diagnostic tool. Current knowledge of the chronology of the responses of myocardial tissue following the occurrence of ischemic insult, as well as the existence of numerous studies aiming to identify reliable markers in dating MI, induced us to investigate the myocardial specimens of MI fatal cases in order to better define the age of MI. We performed an immunohistochemical study and a Western blot analysis to evaluate detectable morphological changes in myocardial specimens of fatal MI cases and to quantify the effects of cardiac expression of inflammatory mediators (CD15, IL-1β, IL-6, TNF-α, IL-15, IL-8, MCP-1, ICAM-1, CD18, tryptase) and structural and functional cardiac proteins. We observed a biphasic course of MCP-1: it was strongly expressed in the very early phase (0-4 hrs), to diminish in the early period (after 6-8 hrs). Again, our choice of IL-15 is explained by the synergism with neutrophilic granulocytes (CD15) and our study shows the potential for striking cytokine synergy in promoting fast, local neutrophil response in damaged tissues. A progressively stronger immunoreaction for the CD15 antibody was visible in the areas where the margination of circulating inflammatory cells was detectable, up to very strong expression in the oldest ones (>12 hours). Further, the induction of CD15, IL-15, MCP-1 expression levels was quantified by Western blot analysis. The results were as follows: IL-15/β-actin 0.80, CD15/β-actin 0.30, and MCP-1/β-actin 0.60, matching perfectly with the results of immunohistochemistry. Control hearts from traumatic death cases did not show any immunoreactivity to the

  3. Anisotropy signature in extended images from reverse-time migration

    KAUST Repository

    Sava, Paul

    2012-11-04

    Reverse-time migration can accurately image complex geologic structures in anisotropic media. Extended images at selected locations in the earth, i.e. at common-image-point gathers (CIPs), carry enough information to characterize the angle-dependent illumination and to provide measurements for migration velocity analysis. Furthermore, inaccurate anisotropy leaves a distinctive signature in CIPs, which can be used to evaluate anisotropy through techniques similar to the ones used in conventional wavefield tomography.

  4. T1 and T2 mapping for evaluation of myocardial involvement in patients with ANCA-associated vasculitides.

    Science.gov (United States)

    Greulich, Simon; Mayr, Agnes; Kitterer, Daniel; Latus, Joerg; Henes, Joerg; Steubing, Hannah; Kaesemann, Philipp; Patrascu, Alexandru; Greiser, Andreas; Groeninger, Stefan; Braun, Niko; Alscher, M Dominik; Sechtem, Udo; Mahrholdt, Heiko

    2017-01-06

    Myocardial involvement in AAV patients might be silent, presenting with no or nonspecific symptoms, normal ECG, and preserved left-ventricular ejection fraction (LV-EF). Since up to 50% of deaths in these patients may be due to myocardial involvement, a reliable diagnostic tool is warranted. In contrast to LGE-CMR, which has its strengths in detecting focal inflammatory or fibrotic processes, recent mapping techniques are able to detect even subtle, diffuse inflammatory or fibrotic processes. Our study sought to investigate ANCA (antineutrophil cytoplasmic antibody) associated vasculitides (AAV) patients for myocardial involvement by a cardiovascular magnetic resonance (CMR) protocol, including late gadolinium enhancement (LGE) and mapping sequences. Thirty seven AAV patients were prospectively enrolled and underwent CMR imaging. Twenty healthy volunteers served as controls. Mean LV-EF was 64%; LGE prevalence of the AAV patients was 43%. AAV patients had higher median native T1 (988 vs. 952 ms, p T1 (488 vs. 524 ms, p = 0.03), expanded extracellular volume (ECV) (27.5 vs. 24.5%, p T1 and T2 in AAV patients showed the highest prevalence of abnormally increased values beyond the 95% percentile of controls. AAV patients demonstrated increased T1, ECV, and T2 values, with native T1 and T2 showing the highest prevalence of values beyond the 95% percentile of normal. Since these findings seem to be independent of LGE, mapping techniques may provide complementary information to LGE-CMR in the assessment of myocardial involvement in patients with AAV.

  5. Cardiac resynchronization therapy evaluated by myocardial scintigraphy with {sup 99m}Tc-MIBI: changes in left ventricular uptake, dyssynchrony, and function

    Energy Technology Data Exchange (ETDEWEB)

    Brandao, Simone C.S.; Nishioka, Silvana A.D.; Giorgi, Maria C.P.; Abe, Rubens; Filho, Martino Martinelli; Hotta, Viviane T.; Vieira, Marcelo L.; Meneghetti, Jose C. [University of Sao Paulo Medical School, Heart Institute (InCor), Sao Paulo, SP (Brazil); Chen, Ji; Garcia, Ernest V. [Emory University, Atlanta, GA (United States)

    2009-06-15

    {sup 99m}Tc-MIBI gated myocardial scintigraphy (GMS) evaluates myocyte integrity and perfusion, left ventricular (LV) dyssynchrony and function. Cardiac resynchronization therapy (CRT) may improve the clinical symptoms of heart failure (HF), but its benefits for LV function are less pronounced. We assessed whether changes in myocardial {sup 99m}Tc-MIBI uptake after CRT are related to improvement in clinical symptoms, LV synchrony and performance, and whether GMS adds information for patient selection for CRT. A group of 30 patients with severe HF were prospectively studied before and 3 months after CRT. Variables analysed were HF functional class, QRS duration, LV ejection fraction (LVEF) by echocardiography, myocardial {sup 99m}Tc-MIBI uptake, LV end-diastolic volume (EDV) and end-systolic volume (ESV), phase analysis LV dyssynchrony indices, and regional motion by GMS. After CRT, patients were divided into two groups according to improvement in LVEF: group 1 (12 patients) with increase in LVEF of 5 or more points, and group 2 (18 patients) without a significant increase. After CRT, both groups showed a significant improvement in HF functional class, reduced QRS width and increased septal wall {sup 99m}Tc-MIBI uptake. Only group 1 showed favourable changes in EDV, ESV, LV dyssynchrony indices, and regional motion. Before CRT, EDV, and ESV were lower in group 1 than in group 2. Anterior and inferior wall {sup 99m}Tc-MIBI uptakes were higher in group 1 than in group 2 (p<0.05). EDV was the only independent predictor of an increase in LVEF (p=0.01). The optimal EDV cut-off point was 315 ml (sensitivity 89%, specificity 94%). The evaluation of EDV by GMS added information on patient selection for CRT. After CRT, LVEF increase occurred in hearts less dilated and with more normal {sup 99m}Tc-MIBI uptake. (orig.)

  6. Regional myocardial blood flow reserve impairment and metabolic changes suggesting myocardial ischemia in patients with idiopathic dilated cardiomyopathy

    NARCIS (Netherlands)

    van den Heuvel, AFM; van Veldhuisen, DJ; van der Wall, EE; Blanksma, PK; Siebelink, HMJ; Vaalburg, WM; van Gilst, WH; Crijns, HJGM

    OBJECTIVES We performed positron emission tomography (PET) to evaluate myocardial ischemia in patients with idiopathic dilated cardiomyopathy (IDC). BACKGROUND Patients with IDC have anatomically normal coronary arteries, and it has been assumed that myocardial ischemia does not occur. METHODS We

  7. Different Causes of Death in Patients with Myocardial Infarction Type 1, Type 2 and Myocardial Injury

    DEFF Research Database (Denmark)

    Lambrecht, S; Sarkisian, Laura; Saaby, Lotte

    2017-01-01

    troponin I measured on clinical indication, were prospectively studied. Patients with at least 1 cardiac troponin I value >30 ng/L underwent case ascertainment and individual evaluation by an experienced adjudication committee. Patients were classified as having type 1 myocardial infarction, type 2...... myocardial infarction or myocardial injury according to the criteria of the Universal definition of myocardial infarction. Follow-up was ensured until December 31st 2014. Data on mortality and causes of death were obtained from the Danish Civil Registration System and the Danish Register of Causes of Death....... RESULTS: Overall, 3762 consecutive patients were followed for a mean of 3.2 years (IQR, 1.3-3.6 years). All-cause mortality differed significantly between categories: Type 1 myocardial infarction 32%, type 2 myocardial infarction 62%, myocardial injury 59%, and 22% in patients with non-elevated troponin...

  8. [Evaluation of postoperative myocardial injury by heart-type fatty acid-binding protein in off-pump coronary artery bypass grafting surgery].

    Science.gov (United States)

    Carmona, P; Mateo, E; Montoro, A; Alós, L; Coret, M; Errando, C L; Llagunes, J; De Andrés, J

    2015-01-01

    Postoperative myocardial infarction is a serious and frequent complication of cardiac surgery. Nonetheless, diagnosis in this context it is occasionally challenging. We sought to evaluate the kinetics and diagnostic accuracy of the new biomarker « heart-type fatty acid-binding protein » (h-FABP) in the early detection of myocardial injury in patients undergoing off-pump coronary artery bypass grafting, compared with classical biomarkers. A prospective study was conducted on 17 consecutive patients who underwent off-pump coronary artery bypass grafting during a 2 month period. Blood samples were drawn for measurement of myocardial ischemic injury biomarkers (h-FABP, troponin, creatine kinase [CK] and CK-MB), at baseline (T1), immediate post-coronary artery bypass grafting (T2), on ICU admission (T3), and after 4 (T4), 8 (T5), 24 (T6) and 48 h (T7). Perioperative ischemic complications, defined according to electrocardiographic, echocardiographic and hemodynamic criteria, were recorded. Earlier biomarkers peak plasma values occurred at T4 with troponin (2.9 ± 5.2 ng/mL), and at T5 with h-FABP (37.9 ± 55.5 ng/mL). Maximum values of CK and CK-MB occurred later, both in T6 (741 ± 779 and 37 ± 51 U/L, respectively). The optimized cut-off obtained for h-FABP was 19 ng/mL, providing a sensitivity and specificity of 77 and 75%, respectively, for diagnosis of perioperative ischemic injury, with an area under the ROC curve for h-FABP of 0.83 (95% CI 0.6-1.0) vs. 0.63 (95% CI 0.33-0.83) for troponin. This cut-off value for h-FABP is reached on average at T2 (mean value of h-FABP at T2: 18.9 ± 21.5 ng/mL). This is the first study evaluating the kinetics of h-FABP biomarker in perioperative off-pump coronary artery bypass grafting, and the cut-off value established could help to extend earlier detection of myocardial ischemia in this context. Copyright © 2014 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S

  9. The myocardial ischemia evaluated by real-time contrast echocardiography may predict the response to cardiac resynchronization therapy: a large animal study.

    Directory of Open Access Journals (Sweden)

    Yongle Chen

    Full Text Available Evidence-based criteria for applying cardiac resynchronization therapy (CRT in patients with ischemic cardiomyopathy are still scarce. The aim of the present study was to evaluate the predictive value of real-time myocardial contrast echocardiography (RT-MCE in a preclinical canine model of ischemic cardiomyopathy who received CRT. Ischemic cardiomyopathy was produced by ligating the first diagonal branch in 20 beagles. Dogs were subsequently divided into two groups that were either treated with bi-ventricular pacing (CRT group or left untreated (control group. RT-MCE was performed at baseline, before CRT, and 4 weeks after CRT. Two-dimensional speckle tracking imaging was used to evaluate the standard deviation of circumferential (Cir12SD, radial (R12SD, and longitudinal (L12SD strains of left ventricular segments at basal as well as middle levels. Four weeks later, the Cir12SD, R12SD, and myocardial blood flow (MBF of the treated group were significantly improved compared to their non-CRT counterparts. Furthermore, MBF values measured before CRT were significantly higher in responders than in non-responders to bi-ventricular pacing. Meanwhile, no significant differences were observed between the responder and non-responder groups in terms of Cir12SD, R12SD, and L12SD. A high degree of correlation was found between MBF values before CRT and LVEF after CRT. When MBF value>24.9 dB/s was defined as a cut-off point before CRT, the sensitivity and specificity of RT-MCE in predicting the response to CRT were 83.3% and 100%, respectively. Besides, MBF values increased significantly in the CRT group compared with the control group after 4 weeks of pacing (49.8±15.5 dB/s vs. 28.5±4.6 dB/s, p<0.05. Therefore, we considered that myocardial perfusion may be superior to standard metrics of LV synchrony in selecting appropriate candidates for CRT. In addition, CRT can improve myocardial perfusion in addition to cardiac synchrony, especially in the setting

  10. Combined evaluation of regional coronary artery calcium and myocardial perfusion by82Rb PET/CT in the identification of obstructive coronary artery disease.

    Science.gov (United States)

    Zampella, Emilia; Acampa, Wanda; Assante, Roberta; Nappi, Carmela; Gaudieri, Valeria; Mainolfi, Ciro Gabriele; Green, Roberta; Cantoni, Valeria; Panico, Mariarosaria; Klain, Michele; Petretta, Mario; Slomka, Piotr J; Cuocolo, Alberto

    2018-01-25

    Cardiac imaging with PET/CT allows measurement of coronary artery calcium (CAC), myocardial perfusion and coronary vascular function. We investigated whether the combined assessment of regional CAC score, ischemic total perfusion deficit (ITPD) and quantitative coronary vascular function would further improve the diagnostic accuracy of PET/CT in predicting obstructive coronary artery disease (CAD). We analyzed 113 patients with suspected CAD referred to 82 Rb PET/CT myocardial perfusion imaging with available coronary angiographic data. Obstructive CAD was defined as ≥75% stenosis. The receiver operating characteristic area under curve (AUC) was applied to evaluate the ability of CAC score, ITPD, hyperemic myocardial blood flow (MBF) and coronary flow reserve (CFR) to identify CAD. Vessels with obstructive CAD (71 vessels) had higher ITPD (4.6 ± 6.2 vs. 0.6 ± 1.3) and lower hyperemic MBF (1.01 ± 0.5 vs. 1.75 ± 0.6 ml/min/g) and CFR (1.56 ± 0.6 vs. 2.38 ± 0.7; all p < 0.001) than those without. In prediction of per-vessel CAD, the AUCs for the models including CAC/ITPD/hyperemic MBF (0.869) and CAC/ITPD/CFR (0.875) were higher (both p < 0.01) than for the model including CAC/ITPD (0.790). Compared with CAC/ITPD, continuous net reclassification improvement was 0.69 (95% bootstrap confidence interval, CI, 0.365-1.088) for the CAC/ITPD/hyperemic MBF model and 0.99 (95% bootstrap CI 0.64-1.26) for the CAC/ITPD/CFR model. Hyperemic MBF and CFR provide incremental information about the presence of CAD over CAC score and perfusion imaging parameters. The combined use of CAC, myocardial perfusion imaging and quantitative coronary vascular function in may help predict more accurately the presence of obstructive CAD.

  11. Myocardial scintigraphy in the diagnosis of myocardial contusion

    Energy Technology Data Exchange (ETDEWEB)

    Terashima, Masayoshi; Shinoda, Mitsutaka; Iwama, Hiroshi; Hirama, Hisao; Hoshino, Toshiaki; Urabe, Shinpei [Central Aizu General Hospital, Fukushima (Japan); Meguro, Taiichiroh

    1996-04-01

    To assess the clinical value of a new fatty acid imaging tracer, {sup 123}I-{beta}-methyl iodophenyl pentadecanoic acid (BMIPP), I-BMIPP and thallium-201 (Tl) dual imaging was performed at rest in fifteen patients with mild blunt chest trauma (mean AIS thoracic 1.4{+-}0.51, mean ISS 6.47{+-}3.50, mean RTS 7.69{+-}0.43). All patients were prospectively evaluated on the basis of serial electrocardiograms (ECG) and cardiac enzyme studies (total CPK). Tl and BMIPP dual scintigrams were performed within 10 days following admission. SPECT images were divided into seven segments, and the segmental images were visually scored according to tracer uptake on a 3 (severely decreased tracer uptake) to 0 (normal) scale. Nine patients had scintigraphic defects and were considered to have a myocardial contusion. ECG findings, AIS, ISS, and CPK levels failed to distinguish between scintigraphically positive patients and scintigraphically negative patients. Five of the 14 hypoperfused segments on BMIPP imaging, showed normal Tl uptake, one showed lower BMIPP uptake than Tl, and the remaining eight showed similar distribution of both tracers. The mismatch between tracer uptake on BMIPP images and Tl images was thought to reflect impaired myocardial fatty acid metabolism. Thus, mild blunt chest trauma results in a higher frequency of traumatic myocardial injury than previously recognized, and BMIPP is a promising radio-pharmaceutical for evaluating impaired myocardial fatty acid metabolism in patients with myocardial contusion. (author).

  12. Optimized Heart Sampling and Systematic Evaluation of Cardiac Therapies in Mouse Models of Ischemic Injury: Assessment of Cardiac Remodeling and Semi-Automated Quantification of Myocardial Infarct Size.

    Science.gov (United States)

    Valente, Mariana; Araújo, Ana; Esteves, Tiago; Laundos, Tiago L; Freire, Ana G; Quelhas, Pedro; Pinto-do-Ó, Perpétua; Nascimento, Diana S

    2015-12-02

    Cardiac therapies are commonly tested preclinically in small-animal models of myocardial infarction. Following functional evaluation, post-mortem histological analysis is essential to assess morphological and molecular alterations underlying the effectiveness of treatment. However, non-methodical and inadequate sampling of the left ventricle often leads to misinterpretations and variability, making direct study comparisons unreliable. Protocols are provided for representative sampling of the ischemic mouse heart followed by morphometric analysis of the left ventricle. Extending the use of this sampling to other types of in situ analysis is also illustrated through the assessment of neovascularization and cellular engraftment in a cell-based therapy setting. This is of interest to the general cardiovascular research community as it details methods for standardization and simplification of histo-morphometric evaluation of emergent heart therapies. © 2015 by John Wiley & Sons, Inc. Copyright © 2015 John Wiley & Sons, Inc.

  13. Adenosine versus regadenoson comparative evaluation in myocardial perfusion imaging: results of the ADVANCE phase 3 multicenter international trial.

    Science.gov (United States)

    Iskandrian, Ami E; Bateman, Timothy M; Belardinelli, Luiz; Blackburn, Brent; Cerqueira, Manuel D; Hendel, Robert C; Lieu, Hsiao; Mahmarian, John J; Olmsted, Ann; Underwood, S Richard; Vitola, João; Wang, Whedy

    2007-01-01

    Earlier phase 1 and 2 studies have shown that regadenoson has desirable features as a stress agent for myocardial perfusion imaging. This multicenter, double-blinded phase 3 trial involved 784 patients at 54 sites. Each patient underwent 2 sets of gated single photon emission computed tomography myocardial perfusion imaging studies: an initial qualifying study with adenosine and a subsequent randomized study with either regadenoson (2/3 of patients) or adenosine. Regadenoson was administered as a rapid bolus (adenosine-regadenoson images and adenosine-adenosine images, lay above a prespecified noninferiority margin. Other prospectively defined safety and tolerability comparisons and supporting analyses were also performed. The average agreement rate based on the median of 3 independent blinded readers was 0.63 +/- 0.03 for regadenoson-adenosine and 0.64 +/- 0.04 for adenosine-adenosine-a 1% absolute difference with the lower limit of the 95% confidence interval lying above the prespecified noninferiority margin. Side-by-side interpretation of regadenoson and adenosine images provided comparable results for detecting reversible defects. The peak increase in heart rate was greater with regadenoson than adenosine, but the blood pressure nadir was similar. A summed symptom score of flushing, chest pain, and dyspnea was less with regadenoson than adenosine (P = .013). This phase 3 trial shows that regadenoson provides diagnostic information comparable to a standard adenosine infusion. There were no serious drug-related side effects, and regadenoson was better tolerated than adenosine.

  14. Metabonomic Strategy to the Evaluation of Chinese Medicine Compound Danshen Dripping Pills Interfering Myocardial Ischemia in Rats

    Directory of Open Access Journals (Sweden)

    Xue Xin

    2013-01-01

    Full Text Available Coronary heart disease (CHD is one of the highest mortality diseases in the world. Traditional Chinese medicine compound Danshen dripping pills (CDDPs have currently made a great achievement in treating CHD. However, the therapeutic mechanism of CDDP is often poorly interpreted. In this study, a GC-MS-based metabonomic study was conducted to assess the holistic efficacy of CDDP for myocardial infarction in male Sprague-Dawley rats, which were divided into the control group, the sham group, the model group, the control + CDDP group, and the model + CDDP, with CDDP at a dose of 107 mg/kg·d (equal to 1.8 mL/kg·d. The metabonomic findings demonstrated great differences of metabolic pattern among sham, model, and the model + CDDP in the orthogonal partial least squares discriminant analysis (OPLS-DA models, which coordinated well with the assessment of plasma biochemistry and histopathological assay. Differentially expressed metabolites suggested that energy metabolism, glycolysis, and lipid metabolism might be disrupted by myocardial infarction. Both the potential metabolic biomarkers and the biochemical histopathological indices were regulated effectively by CDDP.

  15. Preclinical Safety Evaluation of Allogeneic Induced Pluripotent Stem Cell-Based Therapy in a Swine Model of Myocardial Infarction.

    Science.gov (United States)

    Gálvez-Montón, Carolina; Soler-Botija, Carolina; Iborra-Egea, Oriol; Díaz-Güemes, Idoia; Martí, Mercè; Iglesias-García, Olalla; Prat-Vidal, Cristina; Crisóstomo, Verónica; Llucià-Valldeperas, Aida; Perea-Gil, Isaac; Roura, Santiago; Sánchez-Margallo, Francisco M; Raya, Ángel; Bayes-Genis, Antoni

    2017-11-01

    The combination of biomatrices and induced pluripotent stem cell (iPSC) derivatives to aid repair and myocardial scar formation may soon become a reality for cardiac regenerative medicine. However, the tumor risk associated with residual undifferentiated cells remains an important safety concern of iPSC-based therapies. This concern is not satisfactorily addressed in xenotransplantation, which requires immune suppression of the transplanted animal. In this study, we assessed the safety of transplanting undifferentiated iPSCs in an allogeneic setting. Given that swine are commonly used as large animal models in cardiac medicine, we used porcine iPSCs (p-iPSCs) in conjunction with bioengineered constructs that support recovery after acute myocardial infarction. Histopathology analyses found no evidence of p-iPSCs or p-iPSC-derived cells within the host myocardium or biomatrices after 30 and 90 days of follow-up. Consistent with the disappearance of the implanted cells, we could not observe functional benefit of these treatments in terms of left ventricular ejection fraction, cardiac output, ventricular volumes, or necrosis. We therefore conclude that residual undifferentiated iPSCs should pose no safety concern when used on immune-competent recipients in an allogeneic setting, at least in the context of cardiac regenerative medicine.

  16. Evaluation of structural remodeling of the atria with OCT in a chronic rat model of myocardial infarction (Conference Presentation)

    Science.gov (United States)

    Eberle, Melissa M.; Thorn, Stephanie; Young, Lawerence; Pfau, Daniel; Madwed, Jeffrey; Small, Kersten; Kilmas, Michael; Choma, Michael A.; Sinusas, Albert J.

    2017-02-01

    Atrial fibrillation (AF) occurs following myocardial infarction (MI) and is associated with left ventricular dysfunction, which promotes the development of atrial remodeling and permanent atrial fibrosis. The purpose of this study was determining the effects of MI on left atrial (LA) remodeling with and without therapy with an angiotensin converting enzyme inhibition (ACEi) utilizing optical coherence tomography (OCT). As the composition of the myocardial tissue changes during LA remodeling the optical attenuation of the light will also change providing a metric to quantify the structural remodeling process. Lewis rats (240-275 g) underwent either surgical ligation of left coronary artery creating chronic MI, or SHAM surgery. 13 weeks post-surgery, ex vivo OCT imaging was performed of the LA appendage. Depth-resolved, attenuation coefficient volumes were calculated and the resulting atrial wall attenuation values were analyzed for four experimental groups: SHAM, SHAM with ACEi, MI no ACEi, and MI with ACEi. Quantification of tissue attenuation was performed and shown to significantly increase with MI in association with increases in collagen as verified with corresponding histological sectioning. Fractal analysis of the LA wall trabeculation patterns, 100 µm below the surface, was performed to quantify wall thickening associated with LA remodeling. A significant increase in fractal dimension was determined post MI compared to SHAM corresponding to a loss of the trabeculation pattern and wall thickening. The results from this study demonstrate OCT as an imaging technique capable of investigate LA remodeling with high resolution and label-free optical contrast processing.

  17. Effect of ACE inhibitor trandolapril on life expectancy of patients with reduced left-ventricular function after acute myocardial infarction. TRACE Study Group. Trandolapril Cardiac Evaluation

    DEFF Research Database (Denmark)

    Torp-Pedersen, C; Køber, L

    1999-01-01

    BACKGROUND: The survival benefit from the use of inhibitors of angiotensin-converting enzyme (ACE) in patients with acute myocardial infarction is usually presented in terms of risk ratios and lives saved per 1000 people treated. A more relevant way to present the extent of benefit would be in te......BACKGROUND: The survival benefit from the use of inhibitors of angiotensin-converting enzyme (ACE) in patients with acute myocardial infarction is usually presented in terms of risk ratios and lives saved per 1000 people treated. A more relevant way to present the extent of benefit would...... be in terms of an increase in life expectancy, but this approach has not previously been possible because of limited data on long-term outcome. We aimed to calculate the effect of trandolapril on life expectancy with follow-up data from the Trandolapril Cardiac Evaluation (TRACE) Study. METHODS: The TRACE...... they had been followed up for a minimum of 6 years. We estimated life expectancy as median lifetime, which was the time for 50% of the patients to have died. Change in life expectancy is expressed as change in median lifetime. Analysis was by intention to treat. FINDINGS: The life expectancy of patients...

  18. Model of coordination melting of crystals and anisotropy of physical and chemical properties of the surface

    Science.gov (United States)

    Bokarev, Valery P.; Krasnikov, Gennady Ya

    2018-02-01

    Based on the evaluation of the properties of crystals, such as surface energy and its anisotropy, the surface melting temperature, the anisotropy of the work function of the electron, and the anisotropy of adsorption, were shown the advantages of the model of coordination melting (MCM) in calculating the surface properties of crystals. The model of coordination melting makes it possible to calculate with an acceptable accuracy the specific surface energy of the crystals, the anisotropy of the surface energy, the habit of the natural crystals, the temperature of surface melting of the crystal, the anisotropy of the electron work function and the anisotropy of the adhesive properties of single-crystal surfaces. The advantage of our model is the simplicity of evaluating the surface properties of the crystal based on the data given in the reference literature. In this case, there is no need for a complex mathematical tool, which is used in calculations using quantum chemistry or modeling by molecular dynamics.

  19. Correlation between left ventricular diastolic function before and after valve replacement surgery and myocardial ultrastructural changes in patients with left ventricular volume-overloaded valvular heart diseases; Evaluation with gated blood pool scintigraphy using [sup 99m]Tc

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Tomiro (Okayama Univ. (Japan). School of Medicine)

    1993-06-01

    Left ventricular (LV) diastolic functions in 23 patients with aortic regurgitation (AR) and 22 patients with mitral regurgitation (MR) were evaluated by gated blood pool scintigraphy. LV myocardial biopsy was performed during open heart surgery, and LV myocardial ultrastructural changes were evaluated by electron microscope. Correlation between LV diastolic function and myocardial ultrastructural changes was examined. It was suggested that preoperative LV diastolic dysfunction occurred earlier than LV systolic dysfunction in patients with AR and MR. LV early diastolic dysfunction was especially significant in patients with AR. LV systolic function was significantly improved postoperatively compared with LV diastolic function in patients with AR and MR. It was suggested that LV interstitial fibrosis caused LV diastolic dysfunction in patients with AR and MR, and insufficiency of myocardial thickening as compensation in patients with MR. It was presumed that LV diastolic dysfunction was irreversible in patients with AR and MR in the distant postoperative period due to persistence of the preoperative myocardial ultrastructural change, e.g., interstitial fibrosis. These LV diastolic indices measured by gated pool scintigraphy were useful in predicting LV ultrastructural changes and postoperative LV dysfunction in patients with LV volume-overloaded valvular heart disease. (author).

  20. Anisotropy in the deep Earth

    Science.gov (United States)

    Romanowicz, Barbara; Wenk, Hans-Rudolf

    2017-08-01

    Seismic anisotropy has been found in many regions of the Earth's interior. Its presence in the Earth's crust has been known since the 19th century, and is due in part to the alignment of anisotropic crystals in rocks, and in part to patterns in the distribution of fractures and pores. In the upper mantle, seismic anisotropy was discovered 50 years ago, and can be attributed for the most part, to the alignment of intrinsically anisotropic olivine crystals during large scale deformation associated with convection. There is some indication for anisotropy in the transition zone, particularly in the vicinity of subducted slabs. Here we focus on the deep Earth - the lower mantle and core, where anisotropy is not yet mapped in detail, nor is there consensus on its origin. Most of the lower mantle appears largely isotropic, except in the last 200-300 km, in the D″ region, where evidence for seismic anisotropy has been accumulating since the late 1980s, mostly from shear wave splitting measurements. Recently, a picture has been emerging, where strong anisotropy is associated with high shear velocities at the edges of the large low shear velocity provinces (LLSVPs) in the central Pacific and under Africa. These observations are consistent with being due to the presence of highly anisotropic MgSiO3 post-perovskite crystals, aligned during the deformation of slabs impinging on the core-mantle boundary, and upwelling flow within the LLSVPs. We also discuss mineral physics aspects such as ultrahigh pressure deformation experiments, first principles calculations to obtain information about elastic properties, and derivation of dislocation activity based on bonding characteristics. Polycrystal plasticity simulations can predict anisotropy but models are still highly idealized and neglect the complex microstructure of polyphase aggregates with strong and weak components. A promising direction for future progress in understanding the origin of seismic anisotropy in the deep mantle

  1. Voltage Control of Magnetic Anisotropy

    Science.gov (United States)

    Hao, Guanhua; Cao, Shi; Noviasky, Nick; Ilie, Carolina; Sokolov, Andre; Yin, Yuewei; Xu, Xiaoshan; Dowben, Peter

    Pd/Co/Gd2O3/Si heterostructures were fabricated via pulsed laser deposition and e-beam evaporation. Hysteresis loops, obtained by longitudinal magneto-optical Kerr-effect (MOKE) measurements, indicates an initial in-plane magnetic anisotropy. Applying a perpendicular voltage on the sample, the differences between the polar and longitudinal MOKE and anomalous Hall effect data indicates there is a reversible change in magnetic anisotropy, from in-plane to out-of-plane, with applied voltage. Prior work by others suggests that the change in magnetic anisotropy is due to redox reactions at the Co/Gd2O3 interference. Voltage controlled magnetism can result from changing interfacial chemistry and does not always require a magneto-electric coupling tensor.

  2. Long-term prognostic importance of hyperkinesia following acute myocardial infarction. TRACE Study Group. TRAndolapril Cardiac Evaluation

    DEFF Research Database (Denmark)

    Kjøller, E; Køber, L; Jørgensen, S

    1999-01-01

    The long-term prognostic importance of hyperkinesia is unknown following an acute myocardial infarction (AMI). The American Society of Echocardiography recommends that hyperkinesia should not be included in calculation of wall motion index (WMI). The objective of the present study was to determine...... if hyperkinesia should be included in WMI when it is estimated for prognostic purposes following an AMI. Six thousand, six hundred seventy-six consecutive patients were screened 1 to 6 days after AMI in 27 Danish hospitals. WMI was measured in 6,232 patients applying the 9-segment model and the following scoring...... system: 3 for hyperkinesia, 2 for normokinesia, 1 for hypokinesia, 0 for akinesia, and -1 for dyskinesia. All patients were followed with respect to mortality for at least 3 years. WMI was calculated in 2 different ways: 1 including hyperkinetic segments (hyperkinetic-WMI) and the other excluding...

  3. Dual isotope simultaneous imaging to evaluate the effects of intracoronary bone marrow-derived mesenchymal stem cells on perfusion and metabolism in canines with acute myocardial infarction.

    Science.gov (United States)

    Hao, Linjun; Hao, Jin; Fang, Wei; Han, Chunlei; Zhang, Kaixiu; Wang, Xuemei

    2015-07-01

    Stem cell therapy on acute myocardial infarction (AMI) has been performed for over a decade. In the present study, cardiac perfusion, metabolism and function in dogs with AMI treated by intracoronary injection of bone marrow-derived mesenchymal stem cells (MSCs) were evaluated by dual isotope simultaneous acquisition (DISA) of single positron emission computed tomography (SPECT). Dogs (n=12, 20-30 kg) were randomly assigned to two groups: A graft study (n=6) and control group (n=6). Bone marrow mesenchymal aspirate was collected 3 weeks before surgical procedure. Stem cells were induced by 5-azacytidine for differentiation into myocytes. The dog AMI model was produced by blocking the blood stream at 1/3 of the distinct left anterior descending coronary artery for 90 min. For dogs in the grafting group, MSCs were transplanted by intracoronary injection, and for the control group, 0.9% NaCl was injected instead. At 1 and 10 weeks after MSCs were grafted, respectively, SPECT DISA was performed for each dog in the two groups with 99mTc-SPECT MIBI (925 MBq) and 18F-FDG (222 MBq) for evaluation of myocardial perfusion and metabolism. After the dogs were sacrificed, heart tissue was stained by myocyte-specific antibodies for newborn vessels, troponin T and bromodeoxyuridine (BrdU). Following induction by 5-azacytidine, the morphological features with colony formation, microfilament, as well as atrial granules and positive stainings of α-actinin, myosin and troponin I demonstrated strongly that the MSCs differentiated into myocytes. The number of viable myocardial segments was 10 in the grafting group, which was significantly greater compared with the control group. The ejection fraction of the infarcted left ventricle (LVEF,%) increased from 53.80±9.58 to 70.00±7.52 (change, 16.20±2.93) at 1 and 10 weeks after MSCs engraftment, whilst in the control group, LVEF was 50.50±8.02 and 56.50±7.24 (change, 5.50±2.69), respectively. The LVEF difference was statistically

  4. Clinical characteristics of patients on cardiac rehabilitation program after acute myocardial infarction and evaluation of proper prescribing of cardiac medication at hospital discharge

    Directory of Open Access Journals (Sweden)

    Miljković Jelena

    2015-01-01

    Full Text Available Introduction: Myocardial infarction is a major cause of death and disability worldwide. American College of Cardiology (ACC and American Heart Association (AHA have presented several guidelines for the management of patients with acute myocardial infarction. Objective: The aim of this study was to: 1 Investigate the presence and the incidence of well-known, basic risk factors for coronary heart disease (CHD in patients with STEMI and NSTEMI. 2 Evaluate medical therapy prescribed on hospital discharge, and 3 Determine the frequency of invasive strategy performed. Method: We performed an observational study on 84 patients who survived myocardial infarction (39% NSTEMI and 61% STEMI, 4-6 months before admission to the Institute for cardiovascular diseases and rehabilitation Niška Banja. They all attended cardiac rehabilitation program for 2-3 weeks. Based on the interview with the patients and prior medical records, we determined the incidence of risk factors for CHD: age, gender, hypertension, smoking, diabetes mellitus and hyperlipidemia. We investigated the intrahospital treatement of this patients and the incidence of invasive diagnostic procedure performed. The most important aim of this study was to evaluate the medical therapy prescribed upon hospital discharge. We wanted to know if it was optimal (acording to the latest guidelines. Optimal therapy includes: dual antiplatelet agents, β blockers, angiotensin converting enzyme inhibitors (ACEIs or angiotensin receptor blockers (ARBs, statins and nitroglycerin. Results: Patients with NSTEMI were significantly older, more often female and had higher incidence of hypertension, diabetes and raised blood trygliceride levels. Nitrates and calcium blockers were more frequently used in NSTEMI patients. Invasive diagnostic have been performed in almost the same percentage in our two groups (68,6%-STEMI, 69,7%-NSTEMI, same as PCI (percutaneus coronary intervention and CABG (coronary artery bypass

  5. Influence of a history of arterial hypertension and pretreatment blood pressure on the effect of angiotensin converting enzyme inhibition after acute myocardial infarction. Trandolapril Cardiac Evaluation Study

    DEFF Research Database (Denmark)

    Gustafsson, F; Køber, L; Torp-Pedersen, C

    1998-01-01

    inhibition after AMI complicated by left ventricular dysfunction may be of particular importance in patients with a history of arterial hypertension or a relatively high pretreatment blood pressure. However, further investigations are necessary to establish the clinical impact of these results.......OBJECTIVE: To evaluate the influence of a history of arterial hypertension and the level of pretreatment blood pressure on the efficacy of the angiotensin converting enzyme (ACE) inhibitor trandolapril on mortality and morbidity in patients with acute myocardial infarction (AMI) and left...... for a broad spectrum of potential confounders. Also, benefit from ACE inhibition increased with increasing blood pressure at the time of randomization. Significant interactions between benefit from ACE inhibition and hypertension history, and systolic and diastolic blood pressure were found. CONCLUSION: ACE...

  6. Fractal analysis of heart rate dynamics as a predictor of mortality in patients with depressed left ventricular function after acute myocardial infarction. TRACE Investigators. TRAndolapril Cardiac Evaluation

    Science.gov (United States)

    Makikallio, T. H.; Hoiber, S.; Kober, L.; Torp-Pedersen, C.; Peng, C. K.; Goldberger, A. L.; Huikuri, H. V.

    1999-01-01

    A number of new methods have been recently developed to quantify complex heart rate (HR) dynamics based on nonlinear and fractal analysis, but their value in risk stratification has not been evaluated. This study was designed to determine whether selected new dynamic analysis methods of HR variability predict mortality in patients with depressed left ventricular (LV) function after acute myocardial infarction (AMI). Traditional time- and frequency-domain HR variability indexes along with short-term fractal-like correlation properties of RR intervals (exponent alpha) and power-law scaling (exponent beta) were studied in 159 patients with depressed LV function (ejection fraction function. A short-term fractal-like scaling exponent was the most powerful HR variability index in predicting mortality in patients with depressed LV function. Reduction in fractal correlation properties implies more random short-term HR dynamics in patients with increased risk of death after AMI.

  7. Phase 3 study of. beta. -methyl-p-( sup 123 I)-iodophenyl-pentadecanoic acid, a myocardial imaging agent for evaluating fatty acid metabolism; A multi-center trial

    Energy Technology Data Exchange (ETDEWEB)

    Torizuka, Kanji (Fukui Medical School, Matsuoka (Japan)); Yonekura, Yoshiharu; Nishimura, Tsunehiko; Ohtake, Tohru; Bunko, Hisashi; Tamaki, Nagara; Uehara, Toshiisa

    1992-04-01

    A multi-center trial of {beta}-methyl-p-({sup 123}I)-iodophenyl-pentadecanoic acid ({sup 123}I-BMIPP) was performed to assess its clinical usefulness in the evaluation of myocardial fatty acid metabolism in 587 patients with various heart diseases. {sup 123}I-BMIPP showed relatively decreased uptake compared with {sup 201}Tl in the myocardial lesions of 62% of patients with ischemic heart disease (IHD), 39% of those with cardiomyopathy and 32% of those with other heart diseases. In case of myocardial infarction, less uptake of {sup 123}I-BMIPP (Type B) than {sup 201}Tl was more frequently seen in patients with successful recanalization than in those without recanalization. The patients with matched distribution of the two tracers (Type E) increased in the direct proportion to the interval between the onset of myocardial infarction and the radionuclide studies. The uptake of {sup 123}I-BMIPP correlated well with myocardial viability evaluated by {sup 201}Tl exercise-redistribution studies. Type B was frequently seen in the areas with {sup 201}Tl redistribution, while Type E was seen in the fixed defect areas. In the other heart diseases studied, Type E was observed in approximately 60% of patients with dilated or secondary cardiomyopathies. Type B was seen in about 45% of patients with valvular heart diseases and myocarditis. Various types of mismatch between the two tracers were demonstrated in hypertrophic cardiomyopathy and hypertensive heart disease. It is concluded that {sup 123}I-BMIPP is a safe and useful agent for the diagnosis of various heart diseases, since it reflects myocardial fatty acid metabolism. (author)

  8. Flow stress anisotropy in aluminium

    DEFF Research Database (Denmark)

    Juul Jensen, D.; Hansen, N.

    1990-01-01

    The plastic anisotropy of cold-rolled high purity aluminum (99.996%) and commercially pure aluminum (99.6%) has been investigated. Sample parameters were the initial grain size and the degree of plastic strain (ϵ < 3.00). Flow stresses (0.2% offset) were measured at room temperature by uniaxial t...

  9. Classification of myocardial infarction

    DEFF Research Database (Denmark)

    Saaby, Lotte; Poulsen, Tina Svenstrup; Hosbond, Susanne Elisabeth

    2013-01-01

    The classification of myocardial infarction into 5 types was introduced in 2007 as an important component of the universal definition. In contrast to the plaque rupture-related type 1 myocardial infarction, type 2 myocardial infarction is considered to be caused by an imbalance between demand...... and supply of oxygen in the myocardium. However, no specific criteria for type 2 myocardial infarction have been established....

  10. Acute myocardial infarction following a hornet sting

    Directory of Open Access Journals (Sweden)

    Cvetković-Matić Danica

    2009-01-01

    Full Text Available Background. The occurrence of an acute myocardial infarction following a hornet sting has been very rarely reported in the previous literature. Pathogenetic mechanisms include direct action of the venom components on the coronary endothelium and allergic reaction with mediators released from mast cells. The anaphylactic reaction and venom components can produce acute coronary artery thrombosis. Case report. We reported a 45-year-old man with acute myocardial infarction after a hornet sting in the presence of anaphylaxis. We also discussed clinical implications and pathophysiological mechanisms of acute myocardial infarction caused by hymenoptera sting. Conclusion. A case report of this unusual acute myocardial infarction highlights the potential acute myocardial ischemia associated with hymenoptera sting which requests early diagnosis, thorough cardiovascular evaluation and appropriate treatment.

  11. Echocardiographic Algorithm for Post-Myocardial Infarction LV Thrombus: A Gatekeeper for Thrombus Evaluation by Delayed Enhancement CMR.

    Science.gov (United States)

    Weinsaft, Jonathan W; Kim, Jiwon; Medicherla, Chaitanya B; Ma, Claudia L; Codella, Noel C F; Kukar, Nina; Alaref, Subhi; Kim, Raymond J; Devereux, Richard B

    2016-05-01

    The goal of this study was to determine the prevalence of post-myocardial infarction (MI) left ventricular (LV) thrombus in the current era and to develop an effective algorithm (predicated on echocardiography [echo]) to discern patients warranting further testing for thrombus via delayed enhancement (DE) cardiac magnetic resonance (CMR). LV thrombus affects post-MI management. DE-CMR provides thrombus tissue characterization and is a well-validated but an impractical screening modality for all patients after an MI. A same-day echo and CMR were performed according to a tailored protocol, which entailed uniform echo contrast (irrespective of image quality) and dedicated DE-CMR for thrombus tissue characterization. A total of 201 patients were studied; 8% had thrombus according to DE-CMR. All thrombi were apically located; 94% of thrombi occurred in the context of a left anterior descending (LAD) infarct-related artery. Although patients with thrombus had more prolonged chest pain and larger MI (p ≤ 0.01), only 18% had aneurysm on echo (cine-CMR 24%). Noncontrast (35%) and contrast (64%) echo yielded limited sensitivity for thrombus on DE-CMR. Thrombus was associated with stepwise increments in basal → apical contractile dysfunction on echo and quantitative cine-CMR; the echo-measured apical wall motion score was higher among patients with thrombus (p improved overall performance (area under the curve 0.89 ± 0.44) for thrombus compared with ejection fraction (area under the curve 0.80 ± 0.61; p = 0.01). Apical wall motion partitions would have enabled all patients with LV thrombus to be appropriately referred for DE-CMR testing (100% sensitivity and negative predictive value), while avoiding further testing in more than one-half (56% to 63%) of patients. LV thrombus remains common, especially after LAD MI, and can occur even in the absence of aneurysm. Although DE-CMR yielded improved overall thrombus detection, apical wall motion on a noncontrast

  12. Effects of antidepressant treatment following myocardial infarction

    NARCIS (Netherlands)

    Van Melle, Joost P.; De Jonge, Peter; Honig, Adriaan; Schene, Aart H.; Kuyper, Astrid M. G.; Crijns, Harry J. G. M.; Schins, Annique; Tulner, Dorien; Van den Berg, Maarten P.; Ormel, Johan

    Background Depression following myocardial infarction is associated with poor cardiac prognosis. It is unclear whether antidepressant treatment improves long-term depression status and cardiac prognosis. Aims To evaluate the effects of antidepressant treatment compared with usual care in an

  13. Effects of antidepressant treatment following myocardial infarction

    NARCIS (Netherlands)

    van Melle, Joost P.; de Jonge, Peter; Honig, Adriaan; Schene, Aart H.; Kuyper, Astrid M. G.; Crijns, Harry J. G. M.; Schins, Annique; Tulner, Dorien; van den Berg, Maarten P.; Ormel, Johan

    2007-01-01

    BACKGROUND: Depression following myocardial infarction is associated with poor cardiac prognosis. It is unclear whether antidepressant treatment improves long-term depression status and cardiac prognosis. AIMS: To evaluate the effects of antidepressant treatment compared with usual care in an

  14. Mechanisms involved in symptomatic myocardial bridging

    NARCIS (Netherlands)

    Hazenberg, A. J. C.; Jessurun, G. A. J.; Tio, R. A.

    Background. In patients with extensive myocardial bridging, evaluation of its clinical significance remains a challenge. Hypothesis. Sequential invasive testing is feasible and gives more insight into the pathophysiological mechanism of bridging-related angina. Methods. Twelve patients with chest

  15. Evaluation of the Valve Academic Research Consortium-2 Criteria for Myocardial Infarction in Transcatheter Aortic Valve Implantation: A Prospective Observational Study.

    Directory of Open Access Journals (Sweden)

    Lennart Nilsson

    Full Text Available To evaluate the relevance of the individual components of the Valve Academic Research Consortium (VARC-2 criteria for periprocedural myocardial infarction (MI in transcatheter aortic valve implantation (TAVI. The association between biomarkers and adverse procedural outcome has been established. However, the additive prognostic importance of signs and symptoms are more uncertain.A total of 125 consecutive TAVI patients were prospectively included in this study. Biomarkers for MI were analyzed and signs and symptoms according to VARC-2 criteria were collected from clinical records.The criteria of elevated biomarkers and of signs or symptoms were found in 27 (22% and 32 (26% of the patients, respectively. According to VARC-2 definition, 12 (10% had MI. VARC-2 definition of MI, Troponin T (TnT > 600 ng/L, and presence of signs or symptoms correlated with 6 months mortality, prolonged ICU stay, elevation of N-terminal prohormone brain natriuretic peptide, and renal impairment. No signs or symptoms were found in 7 (44% of the patients who fulfilled the criterion of elevated TnT > 600 ng/L. In the group with positive TnT criterion, there were no significant differences between those with and without signs or symptoms in respect to levels of TnT (1014 [585-1720] ng/L versus 704 [515-905] ng/L, p = 0.17 or creatine kinase-MB (36 [25-52] μg/L versus 29 [25-39] μg/L, p = 0.32. In the multivariate Cox regression analysis, TnT > 600 ng/L was the only significant independent variable associated with 6-months postprocedural mortality.Myocardial injury in TAVI, measured with biomarkers, correlates well with adverse procedural outcome. In this study it is also the strongest predictor for early postprocedural mortality. The additional requirement of signs or symptoms for the diagnosis of MI results in omission of a considerable number of clinically significant MI.

  16. Usefulness of high-sensitivity troponin T for the evaluation of patients with acute chest pain and no or minimal myocardial damage.

    Science.gov (United States)

    Sanchis, Juan; Bardají, Alfredo; Bosch, Xavier; Loma-Osorio, Pablo; Marín, Francisco; Sánchez, Pedro L; Núñez, Julio; Carratalá, Arturo; Barrabés, José A

    2012-08-01

    Although high-sensitivity troponins allow early diagnosis of acute myocardial infarction, their role for identification of acute coronary syndrome in patients with normal conventional troponin remains unclear. A total of 446 patients presenting to the emergency department with chest pain and normal troponin (common practice assays) in 2 serial samples were included. Both samples were also centrally analyzed for high-sensitivity troponin T (hs-TnT) (Roche Diagnostics, Basel, Switzerland). Detection (>3 ng/L) and 99th percentile (≥ 14 ng/L) cutoffs of the maximum hs-TnT levels (hs-TnTmax) were considered. The end points were acute coronary syndrome diagnosis and the composite of in-hospital revascularization or 30-day cardiac events. Acute coronary syndrome was adjudicated to 84 patients (19%), and 62 (14%) had the composite end point. In univariate setting, hs-TnTmax >3 ng/L exhibited high sensitivity (87% and 92%, respectively) and negative predictive value (93% and 97%) for both end points, whereas hs-TnTmax ≥ 14 ng/L provided high specificity (90% and 89%), although low positive predictive values (40% and 33%). After adjusting for clinical (pain characteristics and risk factors) and electrocardiographic data, there was a stepped increase of risk across hs-TnTmax categories (≤ 3, >3 but evaluation of patients with chest pain and with no or minimal myocardial damage. The main contribution of hs-TnT is the high negative predictive value of undetectable levels (≤ 3 ng/L). Copyright © 2012 Mosby, Inc. All rights reserved.

  17. Regional Mechanics Determine Collagen Fiber Structure in Healing Myocardial Infarcts

    OpenAIRE

    Fomovsky, Gregory M.; Rouillard, Andrew D; Holmes, Jeffrey W.

    2012-01-01

    Following myocardial infarction, the mechanical properties of the healing infarct are an important determinant of heart function and the risk of progression to heart failure. In particular, mechanical anisotropy (having different mechanical properties in different directions) in the healing infarct can preserve pump function of the heart. Based on reports of different collagen structures and mechanical properties in various animal models, we hypothesized that differences in infarct size, shap...

  18. Magnetic anisotropy of lecithin membranes. A new anisotropy susceptometer.

    OpenAIRE

    Scholz, F.; Boroske, E; Helfrich, W.

    1984-01-01

    Cylindrical giant vesicles prepared from egg lecithin and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) are oriented in an external magnetic field and observed by phase contrast microscopy. The anisotropic part of the diamagnetic susceptibility of the lecithin membrane is determined from the distribution of angles between the magnetic field and the long cylinder axis due to thermal fluctuations. The anisotropy of DMPC is found to be larger by a factor of 2 than that of egg lecithin. This...

  19. Myocardial imaging. Coxsackie myocarditis

    Energy Technology Data Exchange (ETDEWEB)

    Wells, R.G.; Ruskin, J.A.; Sty, J.R.

    1986-09-01

    A 3-week-old male neonate with heart failure associated with Coxsackie virus infection was imaged with Tc-99m PYP and TI-201. The abnormal imaging pattern suggested myocardial infarction. Autopsy findings indicated that the cause was myocardial necrosis secondary to an acute inflammatory process. Causes of abnormal myocardial uptake of Tc-99m PYP in pediatrics include infarction, myocarditis, cardiomyopathy, bacterial endocarditis, and trauma. Myocardial imaging cannot provide a specific cause diagnosis. Causes of myocardial infarction in pediatrics are listed in Table 1.

  20. Determinants of delay between symptoms and hospital admission in 5978 patients with acute myocardial infarction. The TRACE Study Group. Trandolapril Cardiac Evaluation

    DEFF Research Database (Denmark)

    Ottesen, M M; Køber, L; Jørgensen, S

    1996-01-01

    depressions (OR = 0.847, P = 0.01). All these variables, except history of diabetes mellitus, angina pectoris, and chest pain as an initial symptom were also associated with a delay of more than 6 h. Thrombolytic therapy was administered to 55.8% of patients admitted within 2 h of an acute myocardial......The aim of this study was to analyse the influence of patient characteristics on delay between onset of symptoms and hospital admission (patient delay) in acute myocardial infarction, and especially to assess the impact of risk factors for acute myocardial infarction on patient delay. A group...... of 6676 consecutive patients with enzyme-confirmed acute myocardial infarction, admitted alive to 27 Danish hospitals over a 26 month period from 1990 to 1992, were studied. Due to missing information on delay or in-hospital acute myocardial infarction 698 patients were excluded, leaving 5978 patients...

  1. Rationale and Design of a Clinical Trial to Evaluate the Safety and Efficacy of Intracoronary Infusion of Allogeneic Human Cardiac Stem Cells in Patients With Acute Myocardial Infarction and Left Ventricular Dysfunction: The Randomized Multicenter Double-Blind Controlled CAREMI Trial (Cardiac Stem Cells in Patients With Acute Myocardial Infarction).

    Science.gov (United States)

    Sanz-Ruiz, Ricardo; Casado Plasencia, Ana; Borlado, Luis R; Fernández-Santos, María Eugenia; Al-Daccak, Reem; Claus, Piet; Palacios, Itziar; Sádaba, Rafael; Charron, Dominique; Bogaert, Jan; Mulet, Miguel; Yotti, Raquel; Gilaberte, Immaculada; Bernad, Antonio; Bermejo, Javier; Janssens, Stefan; Fernández-Avilés, Franciso

    2017-06-23

    Stem cell therapy has increased the therapeutic armamentarium in the fight against ischemic heart disease and heart failure. The administration of exogenous stem cells has been investigated in patients suffering an acute myocardial infarction, with the final aim of salvaging jeopardized myocardium and preventing left ventricular adverse remodeling and functional deterioration. However, phase I and II clinical trials with autologous and first-generation stem cells have yielded inconsistent benefits and mixed results. In the search for new and more efficient cellular regenerative products, interesting cardioprotective, immunoregulatory, and cardioregenerative properties have been demonstrated for human cardiac stem cells. On the other hand, allogeneic cells show several advantages over autologous sources: they can be produced in large quantities, easily administered off-the-shelf early after an acute myocardial infarction, comply with stringent criteria for product homogeneity, potency, and quality control, and may exhibit a distinctive immunologic behavior. With a promising preclinical background, CAREMI (Cardiac Stem Cells in Patients With Acute Myocardial Infarction) has been designed as a double-blind, 2:1 randomized, controlled, and multicenter clinical trial that will evaluate the safety, feasibility, and efficacy of intracoronary delivery of allogeneic human cardiac stem cell in 55 patients with large acute myocardial infarction, left ventricular dysfunction, and at high risk of developing heart failure. This phase I/II clinical trial represents a novel experience in humans with allogeneic cardiac stem cell in a rigorously imaging-based selected group of acute myocardial infarction patients, with detailed safety immunologic assessments and magnetic resonance imaging-based efficacy end points. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02439398. © 2017 American Heart Association, Inc.

  2. Scintigraphic evaluation of regional myocardial sympathetic activity in patients with hypertrophic cardiomyopathy. Comparison between asymmetrical hypertrophic cardiomyopathy and apical hypertrophy

    Energy Technology Data Exchange (ETDEWEB)

    Eno, Shin; Takeo, Eiichiro; Sasaki, Satoshi; Matsuda, Keiji; Fujii, Hideaki; Kanazawa, Ikuo [Chugoku Rosai General Hospital, Kure, Hiroshima (Japan)

    1998-02-01

    Using {sup 123}I-MIBG (metaiodobenzylguanidine) and {sup 201}Tl imagings, an examination concerning the relation between the hypertrophic region and its sympathetic nervous function was done. Subjects were 12 normal adults (4 males and 8 females, mean age 61.3 yr), 13 patients with asymmetrical hypertrophic cardiomyopathy (10 males and 3 females, 63.9 yr) and 13 patients with apical hypertrophy (9 males and 4 females, 67.2 yr). The SPECT apparatus was Toshiba two-gated gamma camera GCA 7200A. At 20 min and 3 hr after intravenous injection of 111 MBq of {sup 123}I-MIBG, myocardial SPECT and planar images were obtained with collimator LEHR under following conditions: photoelectric peak 159 KeV, window width 20%, matrix size 64 x 64 (256 x 256 for the planar image), step angle 6deg, 40 sec/step and 180deg for 1 camera. In another day, {sup 201}Tl SPECT and planar imagings were performed 10 min after intravenous injection of 111 MBq of {sup 201}Tl for the photoelectric peak 72 KeV under similar conditions to above. SPECT images were reconstructed using Butterworth filter and Shepp and Logan filter. Images were examined for the defect score, myocardium/mediastinum ratio, whole heart washout rate and regional washout rate. In the asymmetrical hypertrophic myopathy, abnormal sympathetic nerve function was recognized on the regions regardless of their disease severity while in the apical hypertrophy, abnormality was restricted on the apical region. Therefore, the two diseases were found different from each other from the aspect of sympathetic nerve functions. (K.H.)

  3. Design and rationale of a multicentre, randomised, double-blind, placebo-controlled clinical trial to evaluate the effect of vitamin D on ventricular remodelling in patients with anterior myocardial infarction: the VITamin D in Acute Myocardial Infarction (VITDAMI) trial

    OpenAIRE

    Tu??n, Jos?; Gonz?lez-Hern?ndez, Ignacio; Llanos-Jim?nez, Luc?a; Alonso-Mart?n, Joaqu?n; Escudier-Villa, Juan M; Tar?n, Nieves; Crist?bal, Carmen; Sanz, Petra; Pello, Ana M; Ace?a, ?lvaro; Carda, Roc?o; Orejas, Miguel; Tom?s, Marta; Beltr?n, Paula; Calero Rueda, Marta

    2016-01-01

    Introduction Decreased plasma vitamin D (VD) levels are linked to cardiovascular damage. However, clinical trials have not demonstrated a benefit of VD supplements on left ventricular (LV) remodelling. Anterior ST-elevation acute myocardial infarction (STEMI) is the best human model to study the effect of treatments on LV remodelling. We present a proof-of-concept study that aims to investigate whether VD improves LV remodelling in patients with anterior STEMI. Methods and analysis The VITami...

  4. Dosimetry in myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Toledo, Janine M.; Trindade, Bruno; Ribeiro, Tarcisio P.C. [Universidade Federal de Minas Gerais (DEN/UFMG), Belo Horizonte (Brazil). Dept. de Engenharia Nuclear. Programa de Pos-Graduacao em Ciencias e Tecnicas Nucleares

    2011-07-01

    This paper conducts a dosimetric investigation on the myocardial perfusion image protocol, together with a literature reviewing, motivated by the significant statistic increasing on mortality, morbidity and disability associated with cardiovascular disease, surpassing infectious diseases. Nuclear Cardiology plays a role n the diagnostic functional evaluation of the heart and in the prognostic of patients with suspected or known cardiac ischemia. In the context of unstable myocardial ischemic syndrome, myocardial perfusion scintigraphy is a non-invasive procedure performed by administering a radiopharmaceutical targeted to the heart. As tool for this study are that the images obtained by thoracic angiotomography and abdominal aorta as a anatomic and functional information for model reproduction in SISCODES - System of Codes for Absorbed Dose Calculations based on Stochastic Methods. Data were manipulated in order to create a voxel computational model of the heart to be running in MCNP - Monte Carlo Neutron Particle Code. . It was assumed a homogeneous distribution of Tl-201 in cardiac muscle. Simulations of the transport of particles through the voxel and the interaction with the heart tissue were performed. As a result, the isodose curves in the heart model are displayed as well as the dose versus volume histogram of the heart muscle. We conclude that the present computational tools can generate doses distributed in myocardial perfusion. (author)

  5. Myocardial perfusion imaging with dual energy CT

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, SMG-SNU Boramae Medical Center, Seoul (Korea, Republic of); De Cecco, Carlo N. [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncology and Pathology, University of Rome “Sapienza”, Rome (Italy); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Spandorfer, Adam; Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States)

    2016-10-15

    Highlights: • Stress dual-energy sCTMPI offers the possibility to directly detect the presence of myocardial perfusion defects. • Stress dual-energy sCTMPI allows differentiating between reversible and fixed myocardial perfusion defects. • The combination of coronary CT angiography and dual-energy sCTMPI can improve the ability of CT to detect hemodynamically relevant coronary artery disease. - Abstract: Dual-energy CT (DECT) enables simultaneous use of two different tube voltages, thus different x-ray absorption characteristics are acquired in the same anatomic location with two different X-ray spectra. The various DECT techniques allow material decomposition and mapping of the iodine distribution within the myocardium. Static dual-energy myocardial perfusion imaging (sCTMPI) using pharmacological stress agents demonstrate myocardial ischemia by single snapshot images of myocardial iodine distribution. sCTMPI gives incremental values to coronary artery stenosis detected on coronary CT angiography (CCTA) by showing consequent reversible or fixed myocardial perfusion defects. The comprehensive acquisition of CCTA and sCTMPI offers extensive morphological and functional evaluation of coronary artery disease. Recent studies have revealed that dual-energy sCTMPI shows promising diagnostic accuracy for the detection of hemodynamically significant coronary artery disease compared to single-photon emission computed tomography, invasive coronary angiography, and cardiac MRI. The aim of this review is to present currently available DECT techniques for static myocardial perfusion imaging and recent clinical applications and ongoing investigations.

  6. Volumetric evaluation of coronary plaque in patients presenting with acute myocardial infarction or stable angina pectoris-a multislice computerized tomography study

    DEFF Research Database (Denmark)

    Hammer-Hansen, Sophia; Kofoed, Klaus Fuglsang; Kelbaek, Henning

    2009-01-01

    BACKGROUND: We hypothesized that unstable clinical presentation of coronary artery disease is associated with distinct characteristics of culprit lesions identifiable by multislice computed tomography (MSCT). METHODS: Patients with non-ST-elevation myocardial infarction (NSTEMI) (n = 57) or stable...

  7. Accordion-Like Honeycombs for Tissue Engineering of Cardiac Anisotropy

    Science.gov (United States)

    Engelmayr, George C.; Cheng, Mingyu; Bettinger, Christopher J.; Borenstein, Jeffrey T.; Langer, Robert; Freed, Lisa E.

    2008-01-01

    Tissue engineered grafts may be useful in myocardial repair, however previous scaffolds have been structurally incompatible with recapitulating cardiac anisotropy. Utilizing microfabrication techniques, a novel accordion-like honeycomb microstructure was rendered in poly(glycerol sebacate) to yield porous, elastomeric 3-D scaffolds with controllable stiffness and anisotropy. Accordion-like honeycomb scaffolds with cultured neonatal rat heart cells demonstrated utility via: (1) closely matched mechanical properties compared to native adult rat right ventricular myocardium, with stiffnesses controlled by polymer curing time; (2) heart cell contractility inducible by electric field stimulation with directionally-dependent electrical excitation thresholds (p<0.05); and (3) greater heart cell alignment (p<0.0001) than isotropic control scaffolds. Prototype bilaminar scaffolds with 3-D interconnected pore networks yielded electrically excitable grafts with multi-layered neonatal rat heart cells. Accordion-like honeycombs can thus overcome principal structural-mechanical limitations of previous scaffolds, promoting the formation of grafts with aligned heart cells and mechanical properties more closely resembling native myocardium. PMID:18978786

  8. Evaluation of myocardial strain and artery elasticity using speckle tracking echocardiography and high-resolution ultrasound in patients with bicuspid aortic valve.

    Science.gov (United States)

    Li, Yang; Deng, You-Bin; Bi, Xiao-Jun; Liu, Ya-Ni; Zhang, Jun; Li, Li

    2016-07-01

    Reduced artery elasticity and reduced myocardial strain were present in patients with bicuspid aortic valve (BAV). Their relation to dilation of proximal aorta is unclear. We aimed to study their relation to dilation of proximal aorta. We studied 57 BAV patients categorized into 2 subgroup according to proximal ascending aortic dimensions (nondilated elasticity and myocardial strain in BAV patients, supporting the need for detailed and extensive vascular and cardiac surveillance in BAV patients.

  9. Evaluation of the global MODIS 30 arc-second spatially and temporally complete snow-free land surface albedo and reflectance anisotropy dataset

    Science.gov (United States)

    Sun, Qingsong; Wang, Zhuosen; Li, Zhan; Erb, Angela; Schaaf, Crystal B.

    2017-06-01

    Land surface albedo is an essential variable for surface energy and climate modeling as it describes the proportion of incident solar radiant flux that is reflected from the Earth's surface. To capture the temporal variability and spatial heterogeneity of the land surface, satellite remote sensing must be used to monitor albedo accurately at a global scale. However, large data gaps caused by cloud or ephemeral snow have slowed the adoption of satellite albedo products by the climate modeling community. To address the needs of this community, we used a number of temporal and spatial gap-filling strategies to improve the spatial and temporal coverage of the global land surface MODIS BRDF, albedo and NBAR products. A rigorous evaluation of the gap-filled values shows good agreement with original high quality data (RMSE = 0.027 for the NIR band albedo, 0.020 for the red band albedo). This global snow-free and cloud-free MODIS BRDF and albedo dataset (established from 2001 to 2015) offers unique opportunities to monitor and assess the impact of the changes on the Earth's land surface.

  10. Assessment of myocardial viability using PET

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Seok Nam [College of Medicine, Ajou University, Suwon (Korea, Republic of)

    2005-02-15

    The potential for recovery of left ventricular dysfunction after myocardial revascularization represents a practical clinical definition for myocardial viability. The evaluation of viable myocardium in patients with severe global left ventricular dysfunction due to coronary artery disease and with regional dysfunction after acute myocardial infarction is an important issue whether left ventricular dysfunction may be reversible or irreversible after therapy. If the dysfunction is due to stunning or hibernation, functional improvement is observed. But stunned myocardium may recover of dysfunction with no revascularization. Hibernation is chronic process due to chronic reduction in the resting myocardial blood flow. There are two types of myocardial hibernation; 'functional hibernation' with preserved contractile reserve and 'structural hibernation' without contractile reserve in segments with preserved glucose metabolism. This review focus on the application of F-18 FDG and other radionuclides to evaluate myocardial viability. In addition the factors influencing predictive value of FDG imaging for evaluating viability and the different criteria for viability are also reviewed.

  11. Evaluation of myocardial deformation in patients with Kawasaki disease using speckle-tracking echocardiography during mid-term follow-up.

    Science.gov (United States)

    Dedeoglu, Reyhan; Barut, Kenan; Oztunc, Funda; Atik, Sezen; Adrovic, Amra; Sahin, Sezgin; Cengiz, Dicle; Kasapcopur, Ozgur

    2017-09-01

    Speckle-tracking echocardiography is a recently developed technique for the evaluation of myocardial deformation or strain. Our objective was to examine strain through a mid-term follow-up of patients with Kawasaki disease. We explored left ventricular mechanics using speckle-tracking echocardiography in 35 patients with a history of Kawasaki disease at least 6 months after the acute phase. We also included 30 healthy children as controls. Strain data sets were acquired for the quantification of left ventricular global strain, segmental strain, and left ventricular ejection fraction. The mean age of our patients was 25.6±15.4 months. At a median follow-up of 57.5 months (16.5-98.2), although both values were in the normal range, the mean left ventricular ejection proportion of patients (57.3%) was a little lower than that of controls (p⩽0.05). Patient strain values at the basal inferoseptal (20.0), basal anterolateral (19.5), apical septal (23.3), and apical inferior (24.0) segments were lower compared with controls. In all, seven patients had coronary aneurysms during follow-up. Kawasaki disease patients with pyuria had lower left ventricular strain at the mid anterior, mid anteroseptal, apical anterior, and apical inferior segments and global longitudinal strain compared with patients with no pyuria (p⩽0.05). In children with a history of Kawasaki disease, impairment of left ventricular mechanics occurs especially within the left anterior descending artery territories.

  12. Three-dimensional echocardiography in the evaluation of global and regional function in patients with recent myocardial infarction: a comparison with magnetic resonance imaging.

    Science.gov (United States)

    Thorstensen, Anders; Dalen, Håvard; Hala, Pavel; Kiss, Gabriel; D'hooge, Jan; Torp, Hans; Støylen, Asbjørn; Amundsen, Brage

    2013-07-01

    We aimed to compare three-dimensional (3D) and two-dimensional (2D) echocardiography in the evaluation of patients with recent myocardial infarction (MI), using late-enhancement magnetic resonance imaging (LE-MRI) as a reference method. Echocardiography and LE-MRI were performed approximately 1 month after first-time MI in 58 patients. Echocardiography was also performed on 35 healthy controls. Left ventricular (LV) ejection fraction by 3D echocardiography (3D-LVEF), 3D wall-motion score (WMS), 2D-WMS, 3D speckle tracking-based longitudinal, circumferential, transmural and area strain, and 2D speckle tracking-based longitudinal strain (LS) were measured. The global correlations to infarct size by LE-MRI were significantly higher (P 12%, and a sensitivity of 73% and a specificity of 95% for identification of segments with transmural infarct extension. Three-dimensional WMS and 2D gray-scale echocardiography showed the strongest correlations to LE-MRI. The tested 3D strain method suffers from low temporal and spatial resolution in 3D acquisitions and added diagnostic value could not be proven. © 2013, Wiley Periodicals, Inc.

  13. System dynamics modeling in the evaluation of delays of care in ST-segment elevation myocardial infarction patients within a tiered health system.

    Directory of Open Access Journals (Sweden)

    Luciano de Andrade

    Full Text Available Mortality rates amongst ST segment elevation myocardial infarction (STEMI patients remain high, especially in developing countries. The aim of this study was to evaluate the factors related with delays in the treatment of STEMI patients to support a strategic plan toward structural and personnel modifications in a primary hospital aligning its process with international guidelines.The study was conducted in a primary hospital localized in Foz do Iguaçu, Brazil. We utilized a qualitative and quantitative integrated analysis including on-site observations, interviews, medical records analysis, Qualitative Comparative Analysis (QCA and System Dynamics Modeling (SD. Main cause of delays were categorized into three themes: a professional, b equipment and c transportation logistics. QCA analysis confirmed four main stages of delay to STEMI patient's care in relation to the 'Door-in-Door-out' time at the primary hospital. These stages and their average delays in minutes were: a First Medical Contact (From Door-In to the first contact with the nurse and/or physician: 7 minutes; b Electrocardiogram acquisition and review by a physician: 28 minutes; c ECG transmission and Percutaneous Coronary Intervention Center team feedback time: 76 minutes; and d Patient's Transfer Waiting Time: 78 minutes. SD baseline model confirmed the system's behavior with all occurring delays and the need of improvements. Moreover, after model validation and sensitivity analysis, results suggested that an overall improvement of 40% to 50% in each of these identified stages would reduce the delay.This evaluation suggests that investment in health personnel training, diminution of bureaucracy, and management of guidelines might lead to important improvements decreasing the delay of STEMI patients' care. In addition, this work provides evidence that SD modeling may highlight areas where health system managers can implement and evaluate the necessary changes in order to improve the

  14. Anisotropy signature in reverse-time migration extended images

    KAUST Repository

    Sava, Paul C.

    2014-11-04

    Reverse-time migration can accurately image complex geologic structures in anisotropic media. Extended images at selected locations in the Earth, i.e., at common-image-point gathers, carry rich information to characterize the angle-dependent illumination and to provide measurements for migration velocity analysis. However, characterizing the anisotropy influence on such extended images is a challenge. Extended common-image-point gathers are cheap to evaluate since they sample the image at sparse locations indicated by the presence of strong reflectors. Such gathers are also sensitive to velocity error that manifests itself through moveout as a function of space and time lags. Furthermore, inaccurate anisotropy leaves a distinctive signature in common-image-point gathers, which can be used to evaluate anisotropy through techniques similar to the ones used in conventional wavefield tomography. It specifically admits a V-shaped residual moveout with the slope of the "V" flanks depending on the anisotropic parameter η regardless of the complexity of the velocity model. It reflects the fourth-order nature of the anisotropy influence on moveout as it manifests itself in this distinct signature in extended images after handling the velocity properly in the imaging process. Synthetic and real data observations support this assertion.

  15. Nitrogen-13-labeled ammonia for myocardial imaging

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, W.F.; Fill, H.R.; Harper, P.V.

    1977-01-01

    Cyclotron-produced nitrogen-13 (half-life 10 min), as labeled ammonia (/sup 13/NH/sub 4//sup +/), has been evaluated as a myocardial perfusion imaging agent. The regional myocardial uptake of /sup 13/NH/sub 4//sup +/ has been shown to be proportional to regional tissue perfusion in animal studies. Intravenously administered /sup 13/NH/sub 4//sup +/ is rapidly cleared from the circulation, being extracted by the liver (15 percent), lungs, myocardium (2 percent--4 percent), brain, kidney, and bladder. Myocardial ammonia is metabolized mainly to glutamine via the glutamine synthetase pathway. Pulmonary uptake is substantial, but usually transient, except in smokers where clearance may be delayed. The positron annihilation irradiation (511 keV) of /sup 13/N may be imaged with a scintillation camera, using either a specially designed tungsten collimator or a pinhole collimator. After early technical problems with collimation and the production method of /sup 13/NH/sub 4//sup +/ were overcome, reproducible high quality myocardial images were consistently obtained. The normal myocardial image was established to be of a homogeneous ''doughnut'' configuration. Imaging studies performed in patients with varying manifestations of ischemic and valvular heart disease showed a high incidence of localized perfusion defects, especially in patients with acute myocardial infarction. Sequential studies at short intervals in patients with acute infarction showed correlation between alterations in regional perfusion and the clinical course of the patient. It is concluded that myocardial imaging with /sup 13/NH/sub 4//sup +/ and a scintillation camera provides a valid and noninvasive means of assessing regional myocardial perfusion. This method is especially suitable for sequential studies of acute cardiac patients at short intervals. Coincidence imaging of the 511 keV annihilation irradiation provides a tomographic and potentially quantitative assessment of the

  16. Ion anisotropies in the outer Jovian magnetosphere

    Science.gov (United States)

    Carbary, J. F.; Krimigis, S. M.; Keath, E. P.; Gloeckler, G.; Axford, W. I.; Armstrong, T. P.

    1981-01-01

    Results are presented from Voyager 1 and 2 low-energy charged particle measurements of ion anisotropies in the outer Jovian magnetosphere (more than about 20 Jupiter radii). These anisotropies are the first observed from an instrument rotating in the spin plane of Jupiter. For the several ion species investigated, all the first-order anisotropies are strongly in the corotational sense throughout most of the Jovian magnetosphere and out to the magnetopause on the dayside. Evidence exists for a small component of outward flow in the corotating region. Beyond about 130-150 Jupiter radii along the Voyager outbound trajectories, the anisotropies suggest a magnetospheric wind flowing outward from Jupiter.

  17. Magnetic anisotropy of ferrosmectic phases

    Science.gov (United States)

    Ponsinet, Virginie; Fabre, Pascale; Veyssié, Madeleine; Cabanel, Régis

    1994-10-01

    A new anisotropic magnetic fluid, called ferrosmectic, is obtained when using a colloidal suspension of submicronic magnetic particles (ferrofluid), as a component in a smectic phase of fluid membranes. These lamellar phases present specific magnetic properties. The anisotropy of their magnetic susceptilities as a function of particles concentration is studied and interpreted : a microscopic mechanism involving a steric hindrance between particles and membranes is used to understand the experimental results. Un nouveau fluide magnétique anisotrope, appelé ferrosmectique, est obtenu lorsque nous utilisons un ferrofluide, c'est-à-dire une suspension colloïdale de particules magnétiques de taille inférieure au micron, comme composant dans la fabrication d'une phase smectique de membranes fluides. Ces phases adoptent des comportements spécifiques sous champ magnétique, et nous présentons ici une étude de l'anisotropie de leur susceptibilité magnétique en fonction de la concentration en particules. Nous interprétons les résultats obtenus par un mécanisme microscopique basé sur l'existence d'une gêne stérique entre membranes et particules.

  18. Manipulating the anisotropy of turbulence

    CERN Document Server

    Chang, Kelken; Bodenschatz, Eberhard

    2011-01-01

    Most turbulence theories apply only to the ideal state of statistically homogeneous and isotropic turbulence. Almost all natural flows, including laboratory flows, are neither. In order to know the extent of the validity of the theories, we need to understand the influence of deviations from this ideal state. In this paper, we describe an experiment in which we not only generate isotropic turbulence, but also turbulence whose level of anisotropy can be varied systematically, while maintaining a certain degree of homogeneity. As a first step toward understanding the effect of anisotropy on turbulence, we report on the isotropy of the velocity structure functions for scales smaller than a characteristic length scale describing the large-scale motions of the flow. Our apparatus was nearly spherical, was filled with air, and generated axisymmetric turbulence. We set the ratio of axial to radial velocity fluctuation amplitudes to various values between 0.6 and 2.3. We then measured two-point velocity structure fun...

  19. Nursing Care in Patient with Acute Myocardial Infarction

    OpenAIRE

    Němec, Pavel

    2016-01-01

    This thesis deals with the issue of acute myocardial infarction in context of prehospital, and hospital care. Specific clinical symptoms, diagnostic procedures, and treatment of acute myocardial infarction are described in the theoretical part. The part is also devoted to nursing care. Emphasis is put especially on prevention of cardiovascular diseases development. The goal is to evaluate nursing care of patients with acute myocardial infarction in prehospital, and later on, hospital care. Th...

  20. Telmisartan in the diabetic murine model of acute myocardial infarction: dual contrast manganese-enhanced and delayed enhancement MRI evaluation of the peri-infarct region.

    Science.gov (United States)

    Toma, Ildiko; Kim, Paul J; Dash, Rajesh; McConnell, Michael V; Nishimura, Dwight; Harnish, Phillip; Yang, Phillip C

    2016-02-05

    A novel MRI technique, employing dual contrast manganese-enhanced MRI (MEMRI) and delayed enhancement MRI (DEMRI), can evaluate the physiologically unstable peri-infarct region. Dual contrast MEMRI-DEMRI enables comprehensive evaluation of telmisartan to salvage the peri-infarct injury to elucidate the underlying mechanism of restoring the ischemic cardiomyopathy in the diabetic mouse model. Dual contrast MEMRI-DEMRI was performed on weeks 1, 2, and 4 following initiation of telmisartan treatment in 24 left anterior descendent artery ligated diabetic mice. The MRI images were analyzed for core infarct, peri-infarct, left ventricular end-diastolic, end-systolic volumes, and the left ventricular ejection fraction (LVEF). Transmission electron microscopy (TEM) and real-time PCR were used for ex vivo analysis of the myocardium. Telmisartan vs. control groups demonstrated significantly improved LVEF at weeks 1, 2, and 4, respectively (33 ± 7 %*** vs. 19 ± 5 %, 29 ± 3 %*** vs. 22 ± 4 %, and 31 ± 2 %*** vs 18 ± 6 %, ***p infarct injury. Telmisartan group significantly salvaged the peri-infarct injury. The myocardial effects were validated by TEM, which confirmed the presence of the injured but viable cardiomyocyte morphology in the peri-infarct region and by flow cytometry of venous blood, which demonstrated significantly increased circulating endothelial progenitor cells (EPCs). The improved cardiac function in ischemic cardiomyopathy of diabetic mice by telmisartan is attributed to the attenuation of the peri-infarct injury by the angiogenic effects of EPCs to salvage the injured cardiomyocytes. Dual-contrast MEMRI-DEMRI technique tracked the therapeutic effects of telmisartan on the injured myocardium longitudinally.

  1. Evaluation of relationship between coronary artery status evaluated by coronary computed tomography angiography and development of cardiomyopathy in carbon monoxide poisoned patients with myocardial injury: a prospective observational study.

    Science.gov (United States)

    Cha, Yong Sung; Kim, Hyun; Lee, Yoonsuk; Kwon, Woocheol; Son, Jung-Woo; Youk, Hyun; Kim, Hyung Il; Kim, Oh Hyun; Park, Kyung Hye; Cha, Kyoung-Chul; Lee, Kang Hyun; Hwang, Sung Oh

    2018-01-01

    Whether coronary artery changes are a main mechanism in the development of carbon monoxide (CO)-induced cardiomyopathy remains unknown. We investigated the effects of coronary artery stenosis on the presence or patterns of cardiomyopathy in CO-poisoned patients with myocardial injury defined as elevation of troponin I. This prospective observational study collected data from consecutive patients who were diagnosed with CO poisoning and myocardial injury during the 24-month study period. Transthoracic echocardiography (TTE) and coronary computed tomography angiography (CCTA) were performed to evaluate cardiac function and coronary artery status. TTE and CCTA were performed in 32 consecutive patients. The observed echocardiographic patterns included non-cardiomyopathy (59.4%), left ventricular global dysfunction (25%), Takotsubo cardiomyopathy (6.3%), and cardiomyopathy matching the distribution of the left anterior descending (LAD) artery (9.4%). Four patients had more than moderate stenosis, while stenoses of the LAD, left circumflex, and right coronary arteries were observed in two (6.3%), three (9.4%), and zero patients, respectively. Patients with coronary artery stenosis did not develop cardiomyopathy except for one patient; this patient also did not have regional wall motion abnormalities (RWMA) matched with the stenosis territory. Because there was no difference in coronary artery stenosis according to the presence or patterns of CO-induced cardiomyopathy, coronary artery stenosis is not the main mechanism for the development of CO-induced cardiomyopathy. Thus, the evaluation of coronary arteries is not necessary in all patients with CO-induced cardiomyopathy unless there is RWMA consistent with ischemic changes in electrocardiograms and elevated troponin I levels.

  2. Myocardial Fibrosis in Athletes.

    NARCIS (Netherlands)

    Schoor, F.R. van de; Aengevaeren, V.L.; Hopman, M.T.E.; Oxborough, D.L.; George, K.P.; Thompson, P.D.; Eijsvogels, T.M.H.

    2016-01-01

    Myocardial fibrosis (MF) is a common phenomenon in the late stages of diverse cardiac diseases and is a predictive factor for sudden cardiac death. Myocardial fibrosis detected by magnetic resonance imaging has also been reported in athletes. Regular exercise improves cardiovascular health, but

  3. Acute myocardial infarction.

    Science.gov (United States)

    Reed, Grant W; Rossi, Jeffrey E; Cannon, Christopher P

    2017-01-14

    Acute myocardial infarction has traditionally been divided into ST elevation or non-ST elevation myocardial infarction; however, therapies are similar between the two, and the overall management of acute myocardial infarction can be reviewed for simplicity. Acute myocardial infarction remains a leading cause of morbidity and mortality worldwide, despite substantial improvements in prognosis over the past decade. The progress is a result of several major trends, including improvements in risk stratification, more widespread use of an invasive strategy, implementation of care delivery systems prioritising immediate revascularisation through percutaneous coronary intervention (or fibrinolysis), advances in antiplatelet agents and anticoagulants, and greater use of secondary prevention strategies such as statins. This seminar discusses the important topics of the pathophysiology, epidemiological trends, and modern management of acute myocardial infarction, focusing on the recent advances in reperfusion strategies and pharmacological treatment approaches. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Review Paper: Myocardial Rupture After Acute Myocardial Infarction ...

    African Journals Online (AJOL)

    Myocardial rupture complications after acute myocardial infarction are infrequent but lethal. They mainly involve rupture of the ventricular free wall, ventricular septum, papillary muscle, or combined. We compare features of different kinds of myocardial ruptures after acute myocardial infarction by reviewing the clinical ...

  5. Higher-order anisotropies in the blast-wave model: Disentangling flow and density field anisotropies

    Energy Technology Data Exchange (ETDEWEB)

    Cimerman, Jakub [Czech Technical University in Prague, FNSPE, Prague (Czech Republic); Comenius University, FMPI, Bratislava (Slovakia); Tomasik, Boris [Czech Technical University in Prague, FNSPE, Prague (Czech Republic); Univerzita Mateja Bela, FPV, Banska Bystrica (Slovakia); Csanad, Mate; Loekoes, Sandor [Eoetvoes Lorand University, Budapest (Hungary)

    2017-08-15

    We formulate a generalisation of the blast-wave model which is suitable for the description of higher-order azimuthal anisotropies of the hadron production. The model includes anisotropy in the density profile as well as an anisotropy in the transverse expansion velocity field. We then study how these two kinds of anisotropies influence the single-particle distributions and the correlation radii of two-particle correlation functions. Particularly we focus on the third-order anisotropy and consideration is given averaging over different orientations of the event plane. (orig.)

  6. VELOCITY ANISOTROPY IN THE NIGER VDELTTXFSEDIMENTS ...

    African Journals Online (AJOL)

    Keywords: Intrinsic velocity anisotropy, Niger Delta, Thomsen's parameters, vertical i transverse isotropy (VT!) Introduction. In seismology, a layer is anisotropic if seismic waves propagate through it at different velocities in different directions. Sedimentary rocks possess some degree of intrinsic velocity anisotropy (Jones and.

  7. Experimental investigation of ultrasonic velocity anisotropy in ...

    Indian Academy of Sciences (India)

    2011-08-02

    Aug 2, 2011 ... anisotropy is manifested in several physical properties of the fluid, like viscosity, which gives rise to novel properties as elasticity and yield stress [1–4]. Hence, experimental investigations of field-induced anisotropy are useful to characterize the physical state of a fluid. But, because the magnetic fluids are ...

  8. Inner Core Anisotropy in Attenuation

    Science.gov (United States)

    Yu, W.; Wen, L.

    2004-12-01

    It is now well established that the compressional velocity in the Earth's inner core varies in both direction and geographic location. The compressional waves travel faster along the polar directions than along the equatorial directions. Such polar-equatorial difference is interpreted as a result of inner core anisotropy in velocity (with a magnitude of about 3%) and such anisotropy appears to be stronger in the ``western hemisphere" (180oW -40oE) than in the ``eastern hemisphere" (40oE-180oE). Along the equatorial paths, the compressional velocity also exhibits a hemispheric pattern with the eastern hemisphere being about 1% higher than the western hemisphere. Possible explanations for the causes of the velocity in anisotropy and the hemispheric difference in velocity along the equatorial paths include different geometric inclusions of melt or different alignments of iron crystals which are known to be anisotropic in velocities. Here, we report an observation of ubiquitous correlation between small (large) amplitude and fast (slow) travel time of the PKIKP waves sampling the top 300 km of the inner core. We study this correlation by jointly analyzing the differential travel times and amplitude ratios of the PKiKP-PKIKP and the PKPbc-PKIKP phases recorded by the Global Seismographic Network (1990-2001), various regional seismic networks (BANJO, BLSP, FREESIA, GEOFON, GEOSCOPE, Kazakhstan, Kyrgyz, MEDNET, and OHP), and several PASSCAL Networks deployed in Alaska and Antarctica (XE: 1999-2001, XF: 1995-1996, and YI: 1998-1999). Our dataset consists of 310 PKiKP-PKIKP and 240 PKPbc-PKIKP phases, selected from a total of more than 16,000 observations. PKIKP waves exhibit relatively smaller amplitudes for those sampling the eastern hemisphere along the equatorial paths and even smaller amplitudes for those sampling the polar paths in the western hemisphere. One simple explanation for the velocity-attenuation relation is that the inner core is anisotropic in attenuation

  9. Cardiac magnetic resonance based evaluation of aortic stiffness and epicardial fat volume in patients with hypertension, diabetes mellitus, and myocardial infarction.

    Science.gov (United States)

    Homsi, Rami; Sprinkart, Alois M; Gieseke, Juergen; Meier-Schroers, Michael; Yuecel, Seyrani; Fischer, Stefan; Nadal, Jennifer; Dabir, Darius; Luetkens, Julian A; Kuetting, Daniel L; Schild, Hans H; Thomas, Daniel K

    2018-01-01

    Background Aortic stiffness and epicardial fat relate to cardiovascular risk. Their relationship with each other and their role with hypertension, diabetes mellitus (DM), and myocardial infarction (MI) can be evaluated by cardiac magnetic resonance (CMR). Purpose To explore an association between aortic stiffness and epicardial as well as paracardial fat volume (EFV and ParaFV, respectively) in hypertensive patients and to relate the results to the presence of DM and MI. Material and Methods A total of 156 hypertensive and 20 non-hypertensive participants were examined at 1.5 Tesla. A 2D-velocity-encoded sequence was acquired to assess aortic pulse wave velocity (PWV in m/s) as a measure of aortic stiffness. A 3D-Dixon sequence was used to determine EFV and ParaFV. Results PWV correlated with EFV (R = 0.474; P hypertensive controls compared to hypertensive patients. EFV and PWV were significantly higher in diabetic hypertensive patients without MI (n = 19; PWV: 10.4 ± 2.9; EFV: 92.5 ± 19.3) compared to hypertension-only patients (n = 84 [no DM or MI]; EFV: 64.8 ± 25.1, PWV: 9.0 ± 2.6; P hypertensive patients. Both were increased in the presence of DM; however, only EFV was increased in the presence of MI. This may relate to the PWV lowering effect of the antihypertensive medication used by hypertensive patients and underscores the benefit of EFV assessment in this regard.

  10. Cell tracking and therapy evaluation of bone marrow monocytes and stromal cells using SPECT and CMR in a canine model of myocardial infarction

    Directory of Open Access Journals (Sweden)

    Merrifield Peter

    2009-04-01

    Full Text Available Abstract Background The clinical application of stem cell therapy for myocardial infarction will require the development of methods to monitor treatment and pre-clinical assessment in a large animal model, to determine its effectiveness and the optimum cell population, route of delivery, timing, and flow milieu. Objectives To establish a model for a in vivo tracking to monitor cell engraftment after autologous transplantation and b concurrent measurement of infarct evolution and remodeling. Methods We evaluated 22 dogs (8 sham controls, 7 treated with autologous bone marrow monocytes, and 7 with stromal cells using both imaging of 111Indium-tropolone labeled cells and late gadolinium enhancement CMR for up to12 weeks after a 3 hour coronary occlusion. Hearts were also examined using immunohistochemistry for capillary density and presence of PKH26 labeled cells. Results In vivo Indium imaging demonstrated an effective biological clearance half-life from the injection site of ~5 days. CMR demonstrated a pattern of progressive infarct shrinkage over 12 weeks, ranging from 67–88% of baseline values with monocytes producing a significant treatment effect. Relative infarct shrinkage was similar through to 6 weeks in all groups, following which the treatment effect was manifest. There was a trend towards an increase in capillary density with cell treatment. Conclusion This multi-modality approach will allow determination of the success and persistence of engraftment, and a correlation of this with infarct size shrinkage, regional function, and left ventricular remodeling. There were overall no major treatment effects with this particular model of transplantation immediately post-infarct.

  11. The Systematic Evaluation of Identifying the Infarct Related Artery Utilizing Cardiac Magnetic Resonance in Patients Presenting with ST-Elevation Myocardial Infarction.

    Directory of Open Access Journals (Sweden)

    Carine E Hamo

    Full Text Available Identification of the infarct-related artery (IRA in patients with STEMI using coronary angiography (CA is often based on the ECG and can be challenging in patients with severe multi-vessel disease. The current study aimed to determine how often percutaneous intervention (PCI is performed in a coronary artery different from the artery supplying the territory of acute infarction on cardiac magnetic resonance imaging (CMR.We evaluated 113 patients from the Reduction of infarct Expansion and Ventricular remodeling with Erythropoetin After Large myocardial infarction (REVEAL trial, who underwent CMR within 4±2 days of revascularization. Blinded reviewers interpreted CA to determine the IRA and CMR to determine the location of infarction on a 17-segment model. In patients with multiple infarcts on CMR, acuity was determined with T2-weighted imaging and/or evidence of microvascular obstruction.A total of 5 (4% patients were found to have a mismatch between the IRA identified on CMR and CA. In 4/5 cases, there were multiple infarcts noted on CMR. Thirteen patients (11.5% had multiple infarcts in separate territories on CMR with 4 patients (3.5% having multiple acute infarcts and 9 patients (8% having both acute and chronic infarcts.In this select population of patients, the identification of the IRA by CA was incorrect in 4% of patients presenting with STEMI. Four patients with a mismatch had an acute infarction in more than one coronary artery territory on CMR. The role of CMR in patients presenting with STEMI with multi-vessel disease on CA deserves further investigation.

  12. Statistical anisotropy from inflationary magnetogenesis

    CERN Document Server

    Giovannini, Massimo

    2016-01-01

    Provided the quantum fluctuations are amplified in the presence of a classical gauge field configuration the resulting curvature perturbations exhibit a mild statistical anisotropy which should be sufficiently weak not to conflict with current observational data. The curvature power spectra induced by weakly anisotropic initial states are computed here for the first time when the electric and the magnetic gauge couplings evolve at different rates as it happens, for instance, in the relativistic theory of van der Waals interactions. After recovering the results valid for coincident gauge couplings, the constraints imposed by the isotropy and the homogeneity of the initial states are discussed. The obtained bounds turn out to be more stringent than naively expected and cannot be ignored when discussing the underlying magnetogenesis scenarios.

  13. Voltage Controlled Perpendicular Magnetic Anisotropy.

    Science.gov (United States)

    Noviasky, Nicholas; Sabirianov, Ildar; Cao, Shi; Zhang, Xiaozhe; Sokolov, Andrei; Kirianov, Eugene; Dowben, Peter; Ilie, Carolina C.; University of Nebraska at Lincoln Team; State University of New York at Oswego Collaboration

    Here we report the voltage controlled perpendicular magnetic anisotropy of a multilayer stack composed of P-type silicon substrate/ Gd2O3/ Co/ Pt grown by pulsed laser deposition (PLD) under ultra-high vacuum conditions. For examination of the voltage effect on magnetic properties of the samples, we performed magneto optical Kerr effect (MOKE) measurements. The results show a clear inverse relationship between voltage and coercivity. The exchange of oxygen ions which occurs at the interface between gadolinium oxide and cobalt may increase the cobalt oxide concentration within the optical interface layer. One potential application for this research could be the creation of a voltage controlled magnetic tunneling junction memory storage device. Proper implementation may be able to combine non-volatility with higher areal densities and low power consumption. NSF Research Experience for Faculty and Students at Undergraduate Institutions Program, UNL- MRSEC.

  14. Azimuthal Anisotropy Results from STAR

    Energy Technology Data Exchange (ETDEWEB)

    Cebra, Daniel

    2013-05-02

    Recent advances in the studies of eventwise azimuthal anisotropy from STAR have been made possible by the high statistics 200 GeV Au + Au datasets taken in 2010 and by the broad range of energies recorded during the first phase of the RHIC beam energy scan. The high statistics full energy Au + Au data have allowed precision studies of flow. These include detailed studies of flow versus non-flow, results of elliptic flow at high p{sub T}, the ν{sub 2} contributions from jets, and elliptic flow of multi-strange hadrons. Data from the beam energy scan enables STAR to search for evidence of the first order phase transition and the onset of deconfinement through the energy systematics of directed flow, elliptic flow, and azimuthally sensitive HBT.

  15. Statistical anisotropy from inflationary magnetogenesis

    Science.gov (United States)

    Giovannini, Massimo

    2016-02-01

    Provided the quantum fluctuations are amplified in the presence of a classical gauge field configuration the resulting curvature perturbations exhibit a mild statistical anisotropy which should be sufficiently weak not to conflict with current observational data. The curvature power spectra induced by weakly anisotropic initial states are computed here for the first time when the electric and the magnetic gauge couplings evolve at different rates as it happens, for instance, in the relativistic theory of van der Waals interactions. After recovering the results valid for coincident gauge couplings, the constraints imposed by the isotropy and the homogeneity of the initial states are discussed. The obtained bounds turn out to be more stringent than naively expected and cannot be ignored when discussing the underlying magnetogenesis scenarios.

  16. Endoscopic retrograde cholangiopancreatography causes reduced myocardial blood flow

    DEFF Research Database (Denmark)

    Christensen, M; Hendel, H W; Rasmussen, V

    2002-01-01

    BACKGROUND AND STUDY AIMS: Previous studies have shown that up to 50% of healthy patients may develop ST-segment changes during upper gastrointestinal endoscopy. The aim of the study was to evaluate myocardial blood flow in patients during endoscopic retrograde cholangiopancreatography (ERCP...... with either of the two methods, while two patients developed signs of ischemia during ERCP with both the Holter tape recording and on myocardial scintigraphy (P = 0.02). CONCLUSIONS: Patients undergoing ERCP may develop true myocardial ischemia with reduced myocardial blood flow. Although this is a small...

  17. Periodontitis and myocardial hypertrophy.

    Science.gov (United States)

    Suzuki, Jun-Ichi; Sato, Hiroki; Kaneko, Makoto; Yoshida, Asuka; Aoyama, Norio; Akimoto, Shouta; Wakayama, Kouji; Kumagai, Hidetoshi; Ikeda, Yuichi; Akazawa, Hiroshi; Izumi, Yuichi; Isobe, Mitsuaki; Komuro, Issei

    2017-04-01

    There is a deep relationship between cardiovascular disease and periodontitis. It has been reported that myocardial hypertrophy may be affected by periodontitis in clinical settings. Although these clinical observations had some study limitations, they strongly suggest a direct association between severity of periodontitis and left ventricular hypertrophy. However, the detailed mechanisms between myocardial hypertrophy and periodontitis have not yet been elucidated. Recently, we demonstrated that periodontal bacteria infection is closely related to myocardial hypertrophy. In murine transverse aortic constriction models, a periodontal pathogen, Aggregatibacter actinomycetemcomitans markedly enhanced cardiac hypertrophy with matrix metalloproteinase-2 activation, while another pathogen Porphyromonas gingivalis (P.g.) did not accelerate these pathological changes. In the isoproterenol-induced myocardial hypertrophy model, P.g. induced myocardial hypertrophy through Toll-like receptor-2 signaling. From our results and other reports, regulation of chronic inflammation induced by periodontitis may have a key role in the treatment of myocardial hypertrophy. In this article, we review the pathophysiological mechanism between myocardial hypertrophy and periodontitis.

  18. Aeromedical transport after acute myocardial infarction

    DEFF Research Database (Denmark)

    Seidelin, Jakob B; Bruun, Niels Eske; Nielsen, Henrik

    2009-01-01

    BACKGROUND: No guidelines exist for the planning of aeromedical repatriation after acute myocardial infarction (AMI). In 2004, we employed a risk evaluation-based decision-making system for repatriation of patients after AMI. The objective was to evaluate the safety of transports during 2005...

  19. 3.0 T magnetic resonance myocardial perfusion imaging for semi-quantitative evaluation of coronary microvascular dysfunction in hypertrophic cardiomyopathy.

    Science.gov (United States)

    Yin, Liang; Xu, Hai-Yan; Zheng, Sui-Sheng; Zhu, Ying; Xiao, Jiang-Xi; Zhou, Wei; Yu, Si-Si; Gong, Liang-Geng

    2017-12-01

    This study aimed to assess coronary microvascular dysfunction (CMD) differences in hypertrophic cardiomyopathy (HCM) patients using cardiac magnetic resonance (CMR) first-pass perfusion and late gadolinium enhancement imaging. Forty-seven patients with HCM and twenty-one healthy volunteers underwent CMR at rest. Imaging protocols included short axis cine, first-pass myocardial perfusion, and late gadolinium enhancement (LGE). Left ventricular end-diastolic wall thickness (EDTH), LGE, time to peak (T peak ), maximal up-slope (Slope max ), and peak signal intensity (SI peak ) were assessed for each myocardial segment. The HCM myocardial segments were grouped by the degree of LGE and hypertrophy. T peak , SI peak , Slope max and EDTH in multiple groups were assessed and compared by ANOVA test/Kruskal-Wallis test. The Spearman correlation test was used to determine the relationships between EDTH, LGE and perfusion parameters (T peak , Slope max and SI peak ). Compared to control group segments, T peak increased while Slope max and SI peak decreased in non-LGE/non-hypertrophic segments and LGE/hypertrophic segments in the HCM group, while T peak increased more significantly in LGE/hypertrophic segments (all p hypertrophic segments of HCM patients, and it may be helpful in the early diagnosis of coronary microvascular dysfunction in HCM. This abnormal perfusion is associated with the severity of myocardial fibrosis and the degree of hypertrophy.

  20. Myocardial bridging in a survivor of sudden cardiac near-death : Role of intracoronary Doppler flow measurements and angiography during dobutamine stress in the clinical evaluation

    NARCIS (Netherlands)

    Tio, RA; VanGelder, IC; Boonstra, PW; Crijns, HJGM

    Extensive myocardial bridging in the left anterior descending coronary artery was found in a 46 year old survivor of sudden cardiac near-death. Positron emission tomography and dobutamine stress echocardiography revealed ischaemia in the myocardium distal to the bridging. Spasm was excluded as cause

  1. CMB Anisotropy of Spherical Spaces

    CERN Document Server

    Aurich, Ralf; Steiner, Frank

    2005-01-01

    The first-year WMAP data taken at their face value hint that the Universe might be slightly positively curved and therefore necessarily finite, since all spherical (Clifford-Klein) space forms M^3 = S^3/Gamma, given by the quotient of S^3 by a group Gamma of covering transformations, possess this property. We examine the anisotropy of the cosmic microwave background (CMB) for all typical groups Gamma corresponding to homogeneous universes. The CMB angular power spectrum and the temperature correlation function are computed for the homogeneous spaces as a function of the total energy density parameter Omega_tot in the large range [1.01, 1.20] and are compared with the WMAP data. We find that out of the infinitely many homogeneous spaces only the three corresponding to the binary dihedral group T*, the binary octahedral group O*, and the binary icosahedral group I* are in agreement with the WMAP observations. Furthermore, if Omega_tot is restricted to the interval [1.00, 1.04], the space described by T* is excl...

  2. Photoionization affected by chemical anisotropy

    Science.gov (United States)

    Gladkikh, V. S.; Burshtein, A. I.

    2007-01-01

    The kinetic constants of rhodamine 3B quenching by N,N-dimethyl aniline were extracted from the very beginning of the quenching kinetics, recently studied in a few solvents of different viscosities. They were well fitted with the conventional kinetic constant definition, provided the radial distribution function of simple liquids was ascribed to the reactant pair distribution and the contact electron transfer rate was different in all the cases. This difference was attributed to the chemical anisotropy averaging by the rotation of reactants, which is the faster in solvents of lower viscosity. With the proper choice of a space dependent encounter diffusion, the whole quenching kinetics was well fitted with an encounter theory, using the Marcus [J. Chem. Phys. 24, 966 (1956); 43, 679 (1965)] transfer rate instead of the contact Collins-Kimball [J. Colloid. Sci. 4, 425 (1949)] approximation. Not only the beginning and middle part of the quenching were equally well fitted, but the long time (Markovian) rate constant was also found to be the same as previously obtained. Moreover, the concentration dependencies of the fluorescence quantum yield and the Stern-Volmer constant were specified and await their experimental verification.

  3. [Development and validation of risk score model for acute myocardial infarction in China: prognostic value thereof for in hospital major adverse cardiac events and evaluation of revascularization].

    Science.gov (United States)

    Wu, Xiao-fan; Lü, Shu-zheng; Chen, Yun-dai; Pan, Wei-qi; Song, Xian-tao; Li, Jing; Liu, Xin; Wang, Xi-zhi; Zhang, Li-jie; Ren, Fang; Luo, Jing-guang

    2008-07-08

    To develop a simple risk score model of in-hospital major adverse cardiac events (MACE) including all-cause mortality, new or recurrent myocardial infarction (MI), and evaluate the efficacy about revascularization on patients with different risk. The basic characteristics, diagnosis, therapy, and in-hospital outcomes of 1512 ACS patients from Global Registry of Acute Coronary Events (GRACE) study of China were collected to develop a risk score model by multivariable stepwise logistic regression. The goodness-of-fit test and discriminative power of the final model were assessed respectively. The best cut-off value for the risk score was used to assess the impact of revascularization for ST-elevation MI (STEMI) and non-ST elevation acute coronary artery syndrome (NSTEACS) on in-hospital outcomes. (1) The following 6 independent risk factors accounted for about 92.5% of the prognostic information: age > or =80 years (4 points), SBP or =90 mm Hg (2 points), Killip II (3 points), Killip III or IV (9 points), cardiac arrest during presentation (4 points), ST-segment elevation (3 points) or depression (5 points) or combination of elevation and depression (4 points) on electrocardiogram at presentation. (2) CHIEF risk model was excellent with Hosmer-Lemeshow goodness-of-fit test of 0.673 and c statistics of 0.776. (3)1301 ACS patients previously enrolled in GRACE study were divided into 2 groups with the best cut-off value of 5.5 points. The impact of revascularization on the in-hospital MACE of the higher risk subsets was stronger than that of the lower risk subsets both in STEMI [OR (95% CI) = 0.32 (0.11, 0.94), chi2 = 5.39, P = 0.02] and NSTEACS [OR (95% CI) = 0.32 (0.06, 0.94), chi2 =4.17, P = 0.04] population. However, both STEMI (61.7% vs. 78.3%, P = 0.000) and NSTEACS (42.0% vs 62.3%, P = 0.000) patients with the risk scores more than 5.5 points had lower revascularization rates. The risk score provides excellent ability to predict in-hospital death or (re) MI

  4. Cellulose and the Control of Growth Anisotropy

    Energy Technology Data Exchange (ETDEWEB)

    Tobias I. Baskin

    2004-04-01

    The authors research aims to understand morphogenesis, focusing on growth anisotropy, a process that is crucial to make organs with specific and heritable shapes. For the award, the specific aims were to test hypotheses concerning how growth anisotropy is controlled by cell wall structure, particularly by the synthesis and alignment of cellulose microfibrils, the predominant mechanical element in the cell wall. This research has involved characterizing the basic physiology of anisotropic expansion, including measuring it at high resolution; and second, characterizing the relationship between growth anisotropy, and cellulose microfibrils. Important in this relationship and also to the control of anisotropic expansion are structures just inside the plasma membrane called cortical microtubules, and the research has also investigated their contribution to controlling anisotropy and microfibril alignment. In addition to primary experimental papers, I have also developed improved methods relating to these objectives as well as written relevant reviews. Major accomplishments in each area will now be described.

  5. Solvent induced supramolecular anisotropy in molecular gels

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, Michael A., E-mail: mroger09@uoguelph.ca [Department of Food Science, University of Guelph, Guelph, Ontario, N3C3X9 (Canada); Corradini, Maria G. [Department of Food Science, University of Massachusetts Amherst, Amherst, MA, 01003 (United States); Emge, Thomas [Department of Chemistry and Biochemistry, Rutgers University, New Brunswick, NJ, 08901 (United States)

    2017-06-15

    Herein is the first report of solvent induced anisotropy in 12-hydroxystearic acid self-assembled fibrillar networks. Increasing the chain length of polar solvent, such as nitriles and ketones, tailored the anisotropy of the fibrillar aggregates. 12HSA molecular gels, comprised of alkanes, exhibited an isotropic fibrillar network irrespective of the alkane chain length. In polar solvents, anisotropy, observed using 2D powder x-ray diffraction profiles, is correlated to a fibrillar supramolecular morphologies in long chain nitriles and ketones while sphereulitic crystals are correlated to x-ray diffraction patterns with an isotropic scatter intensity in short chain ketones and nitriles. These changes directly modify the final physical properties of the gels. - Highlights: • 12-HSA self-assembles into crystalline supramolecular morphologies depending on the solvent. • Alkanes, short chain nitriles and ketones led to 12-HSA displaying supramolecular isotropy. • In long chain nitriles and ketones, 12-HSA displays supramolecular anisotropy.

  6. Cosmology with cosmic microwave background anisotropy

    Indian Academy of Sciences (India)

    .Bp; 98.80.Cq; 98.80.Es. 1. Introduction. The transition to precision cosmology has been spearheaded by measurements of CMB anisotropy and, more recently, polarization. Our understanding of cos- mology and structure formation necessarily ...

  7. An echocardiographic method for selecting high risk patients shortly after acute myocardial infarction, for inclusion in multi-centre studies (as used in the TRACE study). TRAndolapril Cardiac Evaluation

    DEFF Research Database (Denmark)

    Køber, L; Torp-Pedersen, C; Carlsen, J

    1994-01-01

    The aim of our study was to examine if echocardiography can reproducibly be used in a multicentre study to select high risk patients with reduced left ventricular function early after an acute myocardial infarction (MI). In the TRAndolapril Cardiac Evaluation Study (TRACE) patients with reduced...... training course recorded a two-dimensional echocardiographic examination on videotape 2-6 days after MI. Within 24 h, wall motion index (WMI) was visually assessed by one of two cardiologists (examiners) with considerable experience in echocardiography. A WMI of

  8. The Damping Tail of CMB Anisotropies

    OpenAIRE

    Hu, Wayne; White, Martin

    1996-01-01

    By decomposing the damping tail of CMB anisotropies into a series of transfer functions representing individual physical effects, we provide ingredients that will aid in the reconstruction of the cosmological model from small-scale CMB anisotropy data. We accurately calibrate the model-independent effects of diffusion and reionization damping which provide potentially the most robust information on the background cosmology. Removing these effects, we uncover model-dependent processes such as ...

  9. Velocity anisotropy in tidally limited star clusters

    Science.gov (United States)

    Tiongco, Maria A.; Vesperini, Enrico; Varri, Anna Lisa

    2016-02-01

    We explore the long-term evolution of the anisotropy in the velocity space of star clusters starting with different structural and kinematical properties. We show that the evolution of the radial anisotropy strength and its radial variation within a cluster contain distinct imprints of the cluster initial structural properties, dynamical history, and of the external tidal field of its host galaxy. Initially isotropic and compact clusters with small initial values of the ratio of the half-mass to Jacobi radius, rh/rJ, develop a strong radial anisotropy during their long-term dynamical evolution. Many clusters, if formed with small values of rh/rJ, should now be characterized by a significant radial anisotropy increasing with the distance from the cluster centre, reaching its maximum at a distance between 0.2 rJ and 0.4 rJ, and then becoming more isotropic or mildly tangentially anisotropic in the outermost regions. A similar radial variation of the anisotropy can also result from an early violent relaxation phase. In both cases, as a cluster continues its evolution and loses mass, the anisotropy eventually starts to decrease and the system evolves towards an isotropic velocity distribution. However, in order to completely erase the strong anisotropy developed by these compact systems during their evolution, they must be in the advanced stages of their evolution and lose a large fraction of their initial mass. Clusters that are initially isotropic and characterized by larger initial values of rh/rJ, on the other hand, never develop a significant radial anisotropy.

  10. Heisenberg antiferromagnets with exchange and cubic anisotropies

    Energy Technology Data Exchange (ETDEWEB)

    Bannasch, G [MPI fuer Physik komplexer Systeme, 01187 Dresden (Germany); Selke, W, E-mail: selke@physik.rwth-aachen.d [Institut fuer Theoretische Physik, RWTH Aachen University and JARA-SIM, 52056 Aachen (Germany)

    2010-01-01

    We study classical Heisenberg antiferromagnets with uniaxial exchange anisotropy and a cubic anisotropy term on simple cubic lattices in an external magnetic field using ground state considerations and extensive Monte Carlo simulations. In addition to the antiferromagnetic phase field-induced spin-flop and non-collinear, biconical phases may occur. Phase diagrams and critical as well as multicritical phenomena are discussed. Results are compared to previous findings.

  11. Protocols of myocardial perfusion SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong Min [College of Medicine, Chungnam National University, Daejeon (Korea, Republic of)

    2005-02-15

    In myocardial perfusion scintigraphy, the results of this evaluation now confront the practitioner of nuclear medicine with methodological options. Most nuclear cardiologic studies are performed using thallium-201, Tc-99m sestamibi and Tc-99m tertrofosmin. Some part of these studies use some form of pharmacologic stress test. While tailoring each test to the individual is ideal, this may be impractical for a busy department. Accordingly, established protocols to be used for patients with similar clinical presentations will be helpful. The following review presents methodology of various imaging protocols mainly according to the guidelines of nuclear cardiology procedures in American Society of Nuclear Cardiology.

  12. Age-distribution, risk factors and mortality in smokers and non-smokers with acute myocardial infarction: a review. TRACE study group. Danish Trandolapril Cardiac Evaluation

    DEFF Research Database (Denmark)

    Ottesen, M M; Jørgensen, S; Kjøller, E

    1999-01-01

    multivessel disease and atherosclerosis but are more thrombogenic; thrombolytic therapy seems to be more effective among smokers; smoking might result in an increased out-of-hospital mortality rate, by being more arrhythmogenic; and smokers are on average a decade younger than non-smokers at the time......Smoking is a risk factor for acute myocardial infarction; paradoxically, many studies have shown a lower post-infarct mortality among smokers. There are some important differences between smokers and non-smokers, which might explain the observed difference in mortality: smokers have less...... of infarction, and have less concomitant disease. Adjusting for these differences in regression analyses shows that smoking is not an independent risk factor for mortality after acute myocardial infarction. The difference in age and risk factors are responsible for the lower mortality among smokers....

  13. Peak enhancement ratio of myocardium to aorta for identification of myocardial ischemia using dynamic myocardial computed tomography perfusion imaging.

    Science.gov (United States)

    Tanabe, Yuki; Kido, Teruhito; Kurata, Akira; Yokoi, Takahiro; Fukuyama, Naoki; Uetani, Teruyoshi; Nishiyama, Hikaru; Kawaguchi, Naoto; Tahir, Enver; Miyagawa, Masao; Mochizuki, Teruhito

    2017-12-01

    This study aimed to evaluate the feasibility of peak enhancement (PE) ratio of myocardium to aorta (PER) derived from stress dynamic computed tomography myocardial perfusion imaging (CTP) for the detection of myocardial ischemia assessed by magnetic resonance (MR) imaging. Forty-four patients who underwent stress dynamic CTP and MR imaging were retrospectively evaluated. From the time-attenuation curve, myocardial PE, PER, and myocardial blood flow (MBF) were calculated on a segment-based analysis. The correlation between myocardial and aortic PE was assessed by Spearman's correlation, and the differences in myocardial PE and PER between normal and ischemic myocardium were assessed by the Mann-Whitney U-test. The diagnostic accuracies of myocardial PE, PER, and MBF for detecting myocardial ischemia were compared by receiver operating characteristic analysis. Of 704 segments, 258 segments (37%) were diagnosed as myocardial ischemia with MR imaging. Myocardial and aortic PE were significantly correlated in both normal and ischemic segments (r=0.76 and 0.58; pmyocardial PE and PER of ischemic segments were significantly lower than those of normal segments (pmyocardial PE, 78% (67-88%) and 82% (95% CI, 70-91%) for PER, and 81% (95% CI, 73-87%) and 85% (95% CI, 79-92%) for MBF. There was a significantly larger area under the curve for PER (0.87; 95% CI, 0.84-0.90) and MBF (0.88; 95%CI, 0.85-0.91), compared to myocardial PE (0.75; 95% CI, 0.70-0.79) (pmyocardial ischemia, comparable to that of MBF. Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

  14. Using big data from health records from four countries to evaluate chronic disease outcomes : a study in 114 364 survivors of myocardial infarction

    OpenAIRE

    Rapsomaniki, E; Thuresson, M.; Yang, E.; Blin, P.; Hunt, P; Chung, S-C; Stogiannis, D; Pujades Rodriguez, MDM; Timmis, A; Denaxas, SC; Danchin, N.; Stokes, M.; Thomas-Delecourt, F; Emmas, C; Hasvold, P

    2016-01-01

    Aims: to assess the international validity of using hospital record data to compare long-term outcomes in heart attack survivors. Methods and results: we used samples of national, ongoing, unselected record sources to assess three outcomes: cause death; a composite of myocardial infarction (MI), stroke, and all-cause death; and hospitalized bleeding. Patients aged 65 years and older entered the study 1 year following the most recent discharge for acute MI in 2002–11 [n = 54 841 (Sweden), 53 9...

  15. Preclinical evaluation of the engineered stem cell chemokine stromal cell-derived factor 1α analog in a translational ovine myocardial infarction model.

    Science.gov (United States)

    Macarthur, John W; Cohen, Jeffrey E; McGarvey, Jeremy R; Shudo, Yasuhiro; Patel, Jay B; Trubelja, Alen; Fairman, Alexander S; Edwards, Bryan B; Hung, George; Hiesinger, William; Goldstone, Andrew B; Atluri, Pavan; Wilensky, Robert L; Pilla, James J; Gorman, Joseph H; Gorman, Robert C; Woo, Y Joseph

    2014-02-14

    After myocardial infarction, there is an inadequate blood supply to the myocardium, and the surrounding borderzone becomes hypocontractile. To develop a clinically translatable therapy, we hypothesized that in a preclinical ovine model of myocardial infarction, the modified endothelial progenitor stem cell chemokine, engineered stromal cell-derived factor 1α analog (ESA), would induce endothelial progenitor stem cell chemotaxis, limit adverse ventricular remodeling, and preserve borderzone contractility. Thirty-six adult male Dorset sheep underwent permanent ligation of the left anterior descending coronary artery, inducing an anteroapical infarction, and were randomized to borderzone injection of saline (n=18) or ESA (n=18). Ventricular function, geometry, and regional strain were assessed using cardiac MRI and pressure-volume catheter transduction. Bone marrow was harvested for in vitro analysis, and myocardial biopsies were taken for mRNA, protein, and immunohistochemical analysis. ESA induced greater chemotaxis of endothelial progenitor stem cells compared with saline (P<0.01) and was equivalent to recombinant stromal cell-derived factor 1α (P=0.27). Analysis of mRNA expression and protein levels in ESA-treated animals revealed reduced matrix metalloproteinase 2 in the borderzone (P<0.05), with elevated levels of tissue inhibitor of matrix metalloproteinase 1 and elastin in the infarct (P<0.05), whereas immunohistochemical analysis of borderzone myocardium showed increased capillary and arteriolar density in the ESA group (P<0.01). Animals in the ESA treatment group also had significant reductions in infarct size (P<0.01), increased maximal principle strain in the borderzone (P<0.01), and a steeper slope of the end-systolic pressure-volume relationship (P=0.01). The novel, biomolecularly designed peptide ESA induces chemotaxis of endothelial progenitor stem cells, stimulates neovasculogenesis, limits infarct expansion, and preserves contractility in an ovine

  16. Radiosynthesis and preclinical evaluation of [{sup 18}F] 4-(2-fluoroethoxy)-2H-chromen-2-one as a novel myocardial perfusion imaging agent

    Energy Technology Data Exchange (ETDEWEB)

    Bhusari, Arun M.; Degani, Mariam S. [Institute of Chemical Technology, Mumbai (India). Dept. of Pharmaceutical Sciences and Technology; Lakshminarayanan, N.; Pawar, Yogita P.; Moghe, Surendra H.; Rajan, M.G.R. [Bhabha Atomic Research Centre, Mumbai (India). Radiation Medicine Center

    2017-07-01

    Recently we developed [{sup 18}F] 4-(2-fluoroethoxy)-2H-chromen-2-one as a novel {sup 18}F myocardial perfusion imaging radiotracer. It was synthesized in good radiochemical yield (>90%). The total time from radiosynthesis to its purification was less than 40 min, with excellent radiochemical purity (≥99%). It showed good stability over a period of 5 h at room temperature. The partition coefficient (log P) of radiotracer was found to be 2.70, suggesting the lipophilic nature of radiotracer. Ex vivo biodistribution study of radiotracer in normal Wistar rats for 30 min post-injection, demonstrated a good heart uptake (>1.3% ID/g) and favorable pharmacokinetics. Additionally, the radiotracer showed significant excretion (>11% ID) by liver, which is indicative of its rapid clearance. Further, in vivo biodistribution study of radiotracer in New Zealand White rabbit provided the clear PET/CT images of cardiomyocytes and myocardial perfusion. All these experimental findings suggest that [{sup 18}F] 4-(2-fluoroethoxy)-2H-chromen-2-one could be used as a potential hit for myocardial perfusion imaging.

  17. Magnetic anisotropy in pyroxene single crystals

    Science.gov (United States)

    Biedermann, Andrea Regina; Hirt, Ann Marie; Pettke, Thomas; Bender Koch, Christian

    2014-05-01

    Anisotropy of magnetic susceptibility (AMS) is often used as a proxy for the mineral fabric in a rock. This requires understanding the intrinsic magnetic anisotropy of the minerals that define the rock fabric. With their prismatic habit, pyroxenes describe the texture in mafic and ultramafic rocks. Magnetic anisotropy in pyroxene crystals often arises from both paramagnetic and ferromagnetic components that can be separated from high-field magnetic data. The paramagnetic component is related to the silicate lattice, whereas the ferromagnetic part arises from the magnetic properties of ferromagnetic inclusions that were further characterized by isothermal remanent magnetization measurements. These inclusions often have needle-like habit and are located on the well-defined cleavage planes within the pyroxenes. We characterize low-field and high-field AMS in pyroxene single crystals of diverse orthopyroxene and clinopyroxene minerals. In addition to the magnetic measurements, we analyzed their chemical composition and Fe2+/Fe3+ distribution. The anisotropy arising from inclusions in some augite crystals displays consistent principal susceptibility directions, whereas no preferred orientation is found in other crystals. The principal susceptibilities of the paramagnetic component can be related to the crystal lattice, with the intermediate susceptibility parallel to the b-axis, and minimum and maximum in the a-c-plane for diopside, augite and spodumene. The degree of anisotropy increases with iron concentration. Aegirine shows a different behavior; not only is its maximum susceptibility parallel to the c-axis, but the anisotropy degree is also lower in relation to its iron concentration. This possibly relates to a predominance of Fe3+ in aegirine, whereas Fe2+ is dominant in the other minerals. In orthopyroxene, the maximum susceptibility is parallel to the c-axis and the minimum is parallel to b. The degree of anisotropy increases linearly with iron concentration. The

  18. Myocardial reverse remodeling.

    Science.gov (United States)

    Hellawell, Jennifer L; Margulies, Kenneth B

    2012-06-01

    Despite an extensive literature defining the mechanisms and significance of pathological myocardial remodeling, there has been no comprehensive review of the inverse process, often labeled reverse remodeling. Accordingly, the goal of this review is to overview the varied settings in which clinically significant reverse remodeling has been well documented. When available, we reviewed relevant randomized, controlled clinical trials, and meta-analyses with sufficient cardiac imaging data to permit conclusions about reverse remodeling. When these types of studies were not available, relevant case-control studies and case series that employed appropriate methodology were reviewed. Regression of pathological myocardial hypertrophy, chamber shape distortions, and dysfunction occurs in a wide variety of settings. Although reverse remodeling occurs spontaneously in some etiologies of myocardial dysfunction and failure, remodeling is more commonly observed in response to medical, device-based, or surgical therapies, including β-blockers, revascularization, cardiac resynchronization therapy, and valve surgery. Indeed, reverse remodeling following pathophysiologically targeted interventions helps validate that the targeted mechanisms are propelling and/or sustaining pathological remodeling. The diverse clinical settings in which reverse remodeling has been observed demonstrates that myocardial remodeling is bidirectional and occurs across the full spectrum of myocardial disease severity, duration, and etiology. Observations in several settings suggest that recovered hearts are not truly normal despite parallel improvements at organ, tissue, and cellular level. Nevertheless, the link between reverse remodeling and improved outcomes should inspire further research to better understand the mechanisms responsible for both reverse remodeling and persistent deviations from normalcy. © 2010 Blackwell Publishing Ltd.

  19. Myocardial tissue engineering.

    Science.gov (United States)

    Jawad, Hedeer; Lyon, Alex R; Harding, Sian E; Ali, Nadire N; Boccaccini, Aldo R

    2008-01-01

    Regeneration of the infarcted myocardium after a heart attack is one of the most challenging aspects in tissue engineering. Suitable cell sources and optimized biocompatible materials must be identified. In this review, we briefly discuss the current therapeutic options available to patients with heart failure post-myocardial infarction. We describe the various strategies currently proposed to encourage myocardial regeneration, with focus on the achievements in myocardial tissue engineering (MTE). We report on the current cell types, materials and methods being investigated for developing a tissue-engineered myocardial construct. Generally, there is agreement that a 'vehicle' is required to transport cells to the infarcted heart to help myocardial repair and regeneration. Suitable cell source, biomaterials, cell environment and implantation time post-infarction remain obstacles in the field of MTE. Research is being focused on optimizing natural and synthetic biomaterials for tissue engineering. The type of cell and its origin (autologous or derived from embryonic stem cells), cell density and method of cell delivery are also being explored. The possibility is being explored that materials may not only act as a support for the delivered cell implants, but may also add value by changing cell survival, maturation or integration, or by prevention of mechanical and electrical remodelling of the failing heart.

  20. Reverse redistribution. Revisited with myocardial contrast echocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Wonsick; Kwan, Jun; Kim, Sungeun [Inha Univ., Inchon (Korea, Republic of). Hospital

    2000-02-01

    The aim of this study is to better understand the pattern and nature of reverse redistribution (RR) in myocardial perfusion imaging. In 20 consecutive acute myocardial infarction (MI) patients, frequency of RR was correlated with that of subendocardial MI that was detected by myocardial contrast echocardiography (MCE). RR was judged to be present when there was more than one grade of worsening in perfusion on 24 hr delayed images compared with the initial rest images. MCE evaluated no opacification in the subendocardial myocardium to suggest subendocardial MI. Kendall's nonparametric correlation coefficiency was calculated. Concordant cases were 15 of 20 (75%) and correlation was statistically significant (p=0.0285). Our results suggested that RR was correlated with MCE-detected nontransmural MI. (author)

  1. Myocardial Lineage Development

    Science.gov (United States)

    Evans, Sylvia M.; Yelon, Deborah; Conlon, Frank L.; Kirby, Margaret L.

    2010-01-01

    The myocardium of the heart is composed of multiple highly specialized myocardial lineages, including those of the ventricular and atrial myocardium, and the specialized conduction system. Specification and maturation of each of these lineages during heart development is a highly ordered, ongoing process involving multiple signaling pathways and their intersection with transcriptional regulatory networks. Here, we attempt to summarize and compare much of what we know about specification and maturation of myocardial lineages from studies in several different vertebrate model systems. To date, most research has focused on early specification, and while there is still more to learn, less is known about factors that promote subsequent maturation of myocardial lineages required to build the functioning adult heart. PMID:21148449

  2. Myocardial fibrosis in patients with myotonic dystrophy type 1

    DEFF Research Database (Denmark)

    Petri, Helle; Ahtarovski, Kiril Aleksov; Vejlstrup, Niels

    2014-01-01

    , and the association between myocardial fibrosis and abnormal findings on ECG, Holter-monitoring and echocardiography. METHODS: We selected 30 unrelated patients with DM1: 18 patients (10 men, mean age 51 years) with, and 12 patients (7 men, mean age 41 years) without abnormal findings on ECG and Holter-monitoring....... Patients were evaluated with medical history, physical examination, ECG, Holter-monitoring, echocardiography and CMR. RESULTS: Myocardial fibrosis was found in 12/30 (40%, 9 men). The presence of myocardial fibrosis was associated with the following CMR-parameters: increased left ventricular mass (median...... of myocardial fibrosis and abnormal findings on: ECG (p = 0.71), Holter-monitoring (p = 0.27) or echocardiographic measurements of left ventricular volumes, ejection fraction or global longitudinal strain (p = 0.18). CONCLUSION: Patients with DM1 had a high prevalence of myocardial fibrosis which...

  3. Evaluation of carbohydrate cardiac metabolism by the {sup 18}FDG and positron emission tomography in the myocardial infarction with healthy coronaries; Evaluation du metabolisme glucidique cardiaque par le {sup 18}FDG et la tomographie par emission de positons dans l`infarctus myocarde a coronaires saines

    Energy Technology Data Exchange (ETDEWEB)

    Agostini, D.; Quennelle, F. [Service de Medecine Nucleaire et Centre CYCERON, CHU Cote de Nacre, Caen (France); Babatasi, G. [Service de Chirurgie Cadiaque, CHU Cote de Nacre, Caen (France); Grollier, G.; Potier, J.C. [Service de Cardiologie, CHU Cote de Nacre, (France); Bouvard, G. [Service de Medecine Nucleaire et Centre CYCERON, CHU Cote de Nacre, Caen (France)

    1997-12-31

    The aim of this study was to evaluate the regional myocardial metabolism of glucose (RMMG) by positron emission tomography (PET) with fluoro-de-oxy-glucose ({sup 18}FDG) in patients having myocardial infarction with healthy coronaries (MIHC). Four patients (4M, age: 41 {+-} 12 years) have presented: MI with a coronarography showing no significant lesions on the epicardial arteries, an irreversible anterior hypo-perfusion, moderated at {sup 201}Tl scintigraphy and an isotopic FEVG < 50%. After a charge of 50 g glucose per os, the PET acquisition consists in a transmission of 25 min, and a dynamic emission of 60 min after injection IV of an embolus of 185 MBq of {sup 18}FDG. The dynamical images allow measuring RMMG and the static image to define the regions of interest on ventricular transaxial cross sections. A myocardial region embodying the totality of VG, including the septal, anterior and lateral regions and an intracavitary region are handy delimited. A model with 3 compartments is applied to the time-activity curves measured in the VG (input function) and in the myocardium (Patlak`s method) and allows measuring the RMMG. The mean value of RMMG, measured along the VG, is significantly diminished as compared with that measured in healthy subjects. In conclusion, the PET based on {sup 18}FDG shows that the myocardial carbohydrate metabolism is altered in patients afflicted with MIHC

  4. Myocardial dysfunction in pediatric septic shock.

    Science.gov (United States)

    Raj, Shashi; Killinger, James S; Gonzalez, Jennifer A; Lopez, Leo

    2014-01-01

    To evaluate the prevalence and significance of myocardial dysfunction in children with septic shock. Thirty patients with septic shock were evaluated by transthoracic echocardiography within 24 hours of admission to a pediatric critical care unit. Transthoracic echocardiography evaluation included left ventricular (LV) size and function, mitral valve inflow velocities in early and late diastole, mitral valve annular velocities in systole and early and late diastole, and LV myocardial performance index. LV systolic dysfunction was defined as an ejection fraction or shortening fraction z-score 2. Secondary outcomes included troponin I concentration, acute kidney injury, and 28-day mechanical ventilation-free duration. Mortality for the 30 patients (mean age, 9.5 ± 7 years) was 7%. The prevalence of LV systolic and/or diastolic dysfunction was 53% (16 of 30). Eleven patients (37%) had systolic dysfunction, 10 (33%) had diastolic dysfunction, and 5 (17%) had both. Systolic and/or diastolic dysfunction was significantly associated with troponin I level (P = .007) and acute kidney injury (P = .02), but not with ventilation-free duration (P = .12). Kaplan-Meier analyses for pediatric critical care unit and hospital length of stay identified no differences between patients with and those without myocardial dysfunction. Myocardial dysfunction occurs frequently in children with septic shock but might not affect hospital length of stay. Copyright © 2014 Mosby, Inc. All rights reserved.

  5. Increase in mean platelet volume in patients with myocardial bridge.

    Science.gov (United States)

    Bilen, Emine; Tanboga, Ibrahim Halil; Kurt, Mustafa; Kocak, Umran; Ayhan, Huseyin; Keles, Telat; Bozkurt, Engin

    2013-01-01

    Myocardial bridge is associated with atherosclerosis altered in shear stress and endothelial dysfunction. Mean platelet volume (MPV), a determinant of platelet activation, is shown to be related with atherosclerosis and endothelial dysfunction. In this study, we aimed to evaluate platelet function assessed by MPV in patients with myocardial bridge. Forty-two patients with myocardial bridge in the left anterior descending artery (LAD) and 43 age- and gender-matched healthy participants were included in the study. Myocardial bridging was defined as an intramyocardial systolic compression or milking of a segment of an epicardial coronary artery on angiography. For the entire study population, MPV was measured using an automatic blood counter. The study population consisted of 42 patients with myocardial bridge (52.7 ± 10.2, 76.2% male) and 43 age- and sex-matched healthy control participants (52.1 ± 10.4, 74.4% male). Compared to the control group, MPV value was significantly higher in patients with myocardial bridge (8.9 ± 1.24 vs 8.3 ± 0.78; P = .01). Further, there were no significant differences between groups regarding hemoglobin level, platelet count, fasting blood glucose, and creatinine levels. Our study findings indicated that myocardial bridge is associated with elevated MPV values. Our results might partly explain the increased cardiovascular events in patients with myocardial bridge.

  6. Evaluation of the Time Interval between the Beginning of Acute Chest Pain in the Patients with Acute Myocardial Infarction and Admission of them at Coronary Care unit and the Related Factors

    Directory of Open Access Journals (Sweden)

    M. Gharakhani

    2007-07-01

    Full Text Available Introduction & Objective: Nowadays, the most common cause of mortality in Iran is coronary artery diseases. The most serious fact that threat patients is acute myocardial infarction and its complications. First day, especially the first hours after acute myocardial infarction is the most important time for the patient life saving. Our goal in this study is evaluation of the time interval between the beginning of acute chest pain occurrence in the patients with AMI and Admission of these patients at coronary care unit and the factors which affect it.Materials & Methods: This study was a cross-sectional analytic study that was done on 164 patients with definite diagnosis of acute myocardial infarction who were admitted at CCU , Ekbatan Hospital Hamadan. At this study, patients were selected from both sex. Data were entered the questionnaire and then analyzed by SPSS software and t-test.Results: The mean time interval between the beginning of chest pain and admission of these patients at CCU was 282 minutes. The mean time interval between the beginning of chest pain and transfer of the patient to a primary medical center, between entrance to the primary medical and transfer to the emergency ward , and between entrance to the emergency ward and admission at CCU were 207,73 and 28 minutes respectively. Sex, education level, distance between patient’s living location and medical center , chest pain location and chest pain form were the most important factors which affect this delay considerably.Conclusion: In this study, we showed that time delay between the beginning of the chest pain and CCU admission is categorized into three stages. Multi center study, defining of the problems and collecting the data can reduce the mortality rate, complications and cost.

  7. Anisotropy in solar wind plasma turbulence

    Science.gov (United States)

    Oughton, S.; Matthaeus, W. H.; Wan, M.; Osman, K. T.

    2015-01-01

    A review of spectral anisotropy and variance anisotropy for solar wind fluctuations is given, with the discussion covering inertial range and dissipation range scales. For the inertial range, theory, simulations and observations are more or less in accord, in that fluctuation energy is found to be primarily in modes with quasi-perpendicular wavevectors (relative to a suitably defined mean magnetic field), and also that most of the fluctuation energy is in the vector components transverse to the mean field. Energy transfer in the parallel direction and the energy levels in the parallel components are both relatively weak. In the dissipation range, observations indicate that variance anisotropy tends to decrease towards isotropic levels as the electron gyroradius is approached; spectral anisotropy results are mixed. Evidence for and against wave interpretations and turbulence interpretations of these features will be discussed. We also present new simulation results concerning evolution of variance anisotropy for different classes of initial conditions, each with typical background solar wind parameters. PMID:25848082

  8. The expected anisotropy in solid inflation

    Energy Technology Data Exchange (ETDEWEB)

    Bartolo, Nicola; Ricciardone, Angelo [Dipartimento di Fisica e Astronomia ' ' G. Galilei' ' , Università degli Studi di Padova, via Marzolo 8, I-35131, Padova (Italy); Peloso, Marco; Unal, Caner, E-mail: nicola.bartolo@pd.infn.it, E-mail: peloso@physics.umn.edu, E-mail: angelo.ricciardone@pd.infn.it, E-mail: unal@physics.umn.edu [School of Physics and Astronomy, University of Minnesota, 116 Church Street S.E., Minneapolis 55455 (United States)

    2014-11-01

    Solid inflation is an effective field theory of inflation in which isotropy and homogeneity are accomplished via a specific combination of anisotropic sources (three scalar fields that individually break isotropy). This results in specific observational signatures that are not found in standard models of inflation: a non-trivial angular dependence for the squeezed bispectrum, and a possibly long period of anisotropic inflation (to drive inflation, the ''solid'' must be very insensitive to any deformation, and thus background anisotropies are very slowly erased). In this paper we compute the expected level of statistical anisotropy in the power spectrum of the curvature perturbations of this model. To do so, we account for the classical background values of the three scalar fields that are generated on large (superhorizon) scales during inflation via a random walk sum, as the perturbation modes leave the horizon. Such an anisotropy is unavoidably generated, even starting from perfectly isotropic classical initial conditions. The expected level of anisotropy is related to the duration of inflation and to the amplitude of the squeezed bispectrum. If this amplitude is close to its current observational limit (so that one of the most interesting predictions of the model can be observed in the near future), we find that a level of statistical anisotropy F{sup 2} gives frozen and scale invariant vector perturbations on superhorizon scales.

  9. A Prospective Evaluation of a Pre-Specified Absorb BVS Implantation Strategy in ST-Segment Elevation Myocardial Infarction: The BVS STEMI STRATEGY-IT Study.

    Science.gov (United States)

    Ielasi, Alfonso; Campo, Gianluca; Rapetto, Claudio; Varricchio, Attilio; Cortese, Bernardo; Brugaletta, Salvatore; Geraci, Salvatore; Vicinelli, Paolo; Scotto di Uccio, Fortunato; Secco, Gioel Gabrio; Poli, Arnaldo; Nicolini, Elisa; Ishida, Kohki; Latib, Azeem; Tespili, Maurizio

    2017-09-25

    The aim of this study was to assess the feasibility and clinical results following a pre-specified bioresorbable scaffold (Absorb BVS) implantation strategy in patients with ST-segment elevation myocardial infarction (STEMI). Concerns were raised about the safety of Absorb because a non-negligible rate of thrombosis was reported within 30 days and at midterm follow-up after primary percutaneous coronary intervention. This was a prospective, multicenter study of patients with STEMI (study period, 505 patients with STEMI (16.9% of the overall STEMI population) were treated with the Absorb BVS. The mean age was 56.6 ± 9.4 years, and 487 patients (96.4%) were in Killip class I or II at admission. According to the study protocol, direct Absorb implantation was feasible in 47 patients (9.3%), whereas post-dilatation was performed in 468 cases (92.7%). Procedural success was attained in 94.8% of the cases. Dual antiplatelet therapy with ticagrelor or prasugrel was administered at discharge in 481 patients (95.1%). At 30-day follow-up, the hierarchical device-oriented composite endpoint rate was 0.6% (0.4% cardiac death, 0.2% target vessel myocardial infarction and ischemia-driven target lesion revascularization). One episode (0.2%) of probable scaffold thrombosis was reported. A pre-specified Absorb implantation strategy in real-world patients with STEMI undergoing primary percutaneous coronary intervention was feasible and associated with a low 30-day device-oriented composite endpoint rate. Mid- and long-term follow-up is strongly needed to eventually confirm these early results. (Use of BVS in ST-Segment Elevation Myocardial Infarction [STEMI]: The BVS STEMI STRATEGY-IT Prospective Registry [STRATEGY-IT]; NCT02601781). Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  10. Cardioprotective effect of amlodipine in oxidative stress induced by experimental myocardial infarction in rats

    Directory of Open Access Journals (Sweden)

    Sudhira Begum

    2007-12-01

    Full Text Available The present study investigated whether the administration of amlodipine ameliorates oxidative stress induced by experimental myocardial infarction in rats. Adrenaline was administered and myocardial damage was evaluated biochemically [significantly increased serum aspertate aminotransferase (AST, lactate dehydrogenase (LDH and malondialdehyde (MDA levels of myocardial tissue] and histologically (morphological changes of myocardium. Amlodipine was administered as pretreatment for 14 days in adrenaline treated rats. Statistically significant amelioration in all the biochemical parameters supported by significantly improved myocardial morphology was observed in amlodipine pretreatment. It was concluded that amlodipine afforded cardioprotection by reducing oxidative stress induced in experimental myocardial infarction of catecholamine assault.

  11. Differential impact of multi-focus fan beam collimation with L-mode and conventional systems on the accuracy of myocardial perfusion imaging: Quantitative evaluation using phantoms

    Directory of Open Access Journals (Sweden)

    Tatsunori Saho

    2013-10-01

    Full Text Available Introduction: A novel IQ-SPECTTM method has become widely used in clinical studies. The present study compares the quality of myocardial perfusion images (MPI acquired using the IQ-SPECTTM (IQ-mode,conventional (180° apart: C-mode and L-mode (90° apart: L-mode systems. We assessed spatial resolution, image reproducibility and quantifiability using various physical phantoms. Materials and Methods: SPECT images were acquired using a dual-headed gamma camera with C-mode, L-mode, and IQ-mode acquisition systems from line source, pai and cardiac phantoms containing solutions of 99mTc. The line source phantom was placed in the center of the orbit and at ± 4.0, ± 8.0, ± 12.0, ± 16.0 and ± 20.0 cm off center. We examined quantifiability using the pai phantom comprising six chambers containing 0.0, 0.016, 0.03, 0.045, 0.062, and 0.074 MBq/mLof 99m-Tc and cross-calibrating the SPECT counts. Image resolution and reproducibility were quantified as myocardial wall thickness (MWT and %uptake using polar maps. Results: The full width at half maximum (FWHM of the IQ-mode in the center was increased by 11% as compared with C-mode, and FWHM in the periphery was increased 41% compared with FWHM at the center. Calibrated SPECT counts were essentially the same when quantified using IQ-and C-modes. IQ-SPECT images of MWT were significantly improved (P<0.001 over L-mode, and C-mode SPECT imaging with IQ-mode became increasingly inhomogeneous, both visually and quantitatively (C-mode vs. L-mode, ns; C-mode vs. IQ-mode, P<0.05. Conclusion: Myocardial perfusion images acquired by IQ-SPECT were comparable to those acquired by conventional and L-mode SPECT, but with significantly improved resolution and quality. Our results suggest that IQ-SPECT is the optimal technology for myocardial perfusion SPECT imaging.

  12. Evaluation of the therapeutic effect of hyperbaric oxygenation and erythropoietin in the treatment of chronic heart failure using myocardial perfusion scintigraphy G-SPECT

    Directory of Open Access Journals (Sweden)

    Baškot Branislav

    2009-01-01

    Full Text Available Background. The most important predictors of longterm survival in patients with cardiac ischemic disease are left ventricular ejection fraction, left ventricular volumes, infarction size, presence and extent of residual myocardial ischemia. One of the most important recent developments in single photon emission computed tomography (SPECT myocardial perfusion imaging is the ability to acquire these studies in conjunction with electrocardiogram (ECG gating (G-SPECT. The ability to asses radionuclide myocardial perfusion and function with ECG G-SPECT imaging has revolutionized this field of nuclear cardiology. Study with G-SPECT development algorithms permits to quantify measures of left ventricular (LV volume, ejection fraction (LVEF and even regional myocardial wall motion and thickening. The American Society of Nuclear Cardiology (ASNC in its position paper from March 1999 recommends the routine incorporation of G-SPECT during cardiac perfusion scintigraphy. Case report. We presented a 70-year-old male with ischemic heart disease (dilatative, cardiomyopathy and absolute arrhythmia. He was few times hospitally treated by medicamentous therapy with no evidence of improvement. After hospital treatment, we included hyperbaric oxygenation (HBO and erythropoietin injections. Hyperbaric oxygenation was carried out in a monoplace hyperbaric chamber, BLK S-303, by a graduated protocol for patients with severe heart insufficiency, totally 15 treatments. Recombinant erythropoietin beta (RecormonR F. Hoffmann-La Roche was applied deeply subcutaneously, every second day from 2 000 IU to totally 16 000 IU. Before the therapy G-SPECT study was performed with 99m technetium-MIBI, and we obtained the functional parameters and perfusion of the left ventricle to follow-up the therapy effects. The study was performed by an ADAC-VERTEX PLUS-EPIC two-head gamma camera with dedicated quantitatively algorithm Auto-QUANT. The results of LVEF were 15%, with severity

  13. Three-dimensional phase-sensitive inversion recovery sequencing in the evaluation of left ventricular myocardial scars in ischemic and non-ischemic cardiomyopathy: Comparison to three-dimensional inversion recovery sequencing

    Energy Technology Data Exchange (ETDEWEB)

    Kido, Tomoyuki, E-mail: tomozo0421@gmail.com [Department of Radiology, Ehime University Graduate School of Medicine (Japan); Kido, Teruhito; Nakamura, Masashi; Kawaguchi, Naoto; Nishiyama, Yoshiko [Department of Radiology, Ehime University Graduate School of Medicine (Japan); Ogimoto, Akiyoshi [Department of Cardiovascular Internal Medicine, Ehime University Graduate School of Medicine (Japan); Miyagawa, Masao; Mochizuki, Teruhito [Department of Radiology, Ehime University Graduate School of Medicine (Japan)

    2014-12-15

    Highlights: • We evaluate 3D PSIR compared with 3D IR for the detection of myocardial scars. • In image quality, there was no significant difference between IR and PSIR. • A quantitative analysis of LGE volume shows a strong correlation between PSIR and IR. • PSIR detected greater LGE volume in non-ischemic cardiomyopathy patients than IR. • PSIR may have a specific role in scar evaluation of non-ischemic cardiomyopathy. - Abstract: Background: Late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) is a useful technique for detecting myocardial fibrosis. LGE images are typically acquired using the inversion recovery (IR) method. Recently, phase-sensitive inversion recovery (PSIR) technology has been developed. The purpose of this study was to evaluate free-breathing 3D PSIR sequencing in comparison with breath-held 3D IR sequencing for the detection of myocardial fibrosis. Methods: One hundred twenty-three patients with suspected ischemic cardiac disease (n = 27) or non-ischemic cardiomyopathy (hypertrophic cardiomyopathy, n = 29; dilated cardiomyopathy, n = 22; sarcoidosis, n = 21; arrhythmia, n = 9; myocarditis, n = 4; amyloidosis, n = 3; and others, n = 8) were evaluated by LGE–MRI, which was performed first with the IR sequence and then with the PSIR sequence, using a 3 T MRI scanner. Image quality was scored by two independent readers using a four-point scale. The 3D LGE volume was analyzed quantitatively and compared between both sequencing methods. Results: There was no significant difference in overall image quality (p = 0.19). LGE was detected in 73 patients, who were evaluated visually. Ultimately, 58 patients with acceptable image quality were enrolled in further quantitative analyses (volume assessment). Although quantification of LGE volume revealed a strong correlation between both methods, larger LGE volumes were detected with PSIR compared to IR in patients suspected of non-ischemic cardiomyopathy (39.5 ± 25.9 cm{sup 3} for

  14. Psychophysics and the anisotropy of time.

    Science.gov (United States)

    Riemer, Martin

    2015-12-15

    In psychophysics, experimental control over the presented stimuli is an important prerequisite. Due to the anisotropy of time, this prerequisite is not given in psychophysical experiments on time perception. Many important factors (e.g., the direction of perceived time flow) cannot be manipulated in timing experiments. The anisotropy of time is a peculiarity, which distinguishes the time dimension from other perceptual qualities. Here I summarize the anisotropy-related differences between the perception of time and the perception of other qualities. It is discussed to what extent these differences might affect results and interpretations in psychophysical experiments. In conclusion, I argue for a 'view from nowhen' on the psychophysical study of time perception. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Large directional optical anisotropy in multiferroic ferroborate

    Science.gov (United States)

    Kuzmenko, A. M.; Dziom, V.; Shuvaev, A.; Pimenov, Anna; Schiebl, M.; Mukhin, A. A.; Ivanov, V. Yu.; Gudim, I. A.; Bezmaternykh, L. N.; Pimenov, A.

    2015-11-01

    One of the most fascinating and counterintuitive recent effects in multiferroics is directional anisotropy, the asymmetry of light propagation with respect to the direction of propagation. In such case the absorption in a material can be different for opposite directions. Besides absorption, different velocities of light for different directions of propagation may be also expected, which is termed directional birefringence. In this work, we demonstrate large directional anisotropy in multiferroic samarium ferroborate. The effect is observed for linear polarization of light in the range of millimeter wavelengths, and it survives down to low frequencies. The dispersion and absorption close to the electromagnon resonance can be controlled by external magnetic field and are fully suppressed in one direction. By changing the geometry of the external field, samarium ferroborate shows giant optical activity, which makes this material a universal tool for optical control: with a magnetic field as an external parameter it allows switching between two functionalities: polarization rotation and directional anisotropy.

  16. Large Friction Anisotropy of a Polydiacetylene Monolayer

    Energy Technology Data Exchange (ETDEWEB)

    Burns, A.R.; Carpick, R.W.; Sasaki, D.Y.

    1999-05-11

    Friction force microscopy measurements of a polydiacetylene monolayer film reveal a 300% friction anisotropy that is correlated with the film structure. The film consists of a monolayer of the red form of N-(2-ethanol)- 10,12 pentacosadiynamide, prepared on a Langmuir trough and deposited on a mica substrate. As confirmed by atomic force microscopy and fluorescence microscopy, the monolayer consists of domains of linearly oriented conjugated backbones with pendant hydrocarbon side chains above and below the backbones. Maximum friction occurs when the sliding direction is perpendicular to the backbone. We propose that the backbones impose anisotropic packing of the hydrocarbon side chains which leads to the observed friction anisotropy. Friction anisotropy is therefore a sensitive, optically-independent indicator of polymer backbone direction and monolayer structural properties.

  17. Evaluation of specific neural marker GAP-43 and TH combined with Masson-trichrome staining for forensic autopsy cases with old myocardial infarction.

    Science.gov (United States)

    Yu, Tian-Shui; Wang, Xu; Zhang, Hai-Dong; Bai, Ru-Feng; Zhao, Rui; Guan, Da-Wei

    2018-01-01

    It has been a puzzling forensic task to determine the cause of death as a result of old myocardial infarction (OMI) in the absence of recognizable acute myocardial infarction. Recent studies indicated that the heterogeneous cardiac nerve sprouting and sympathetic hyperinnervation at border zones of the infarcted site played important roles in sudden cardiac death (SCD). So, the present study explored the value of growth associated protein-43 (GAP-43) and tyrosine hydroxylase (TH) as objective and specific neural biomarkers combined with Masson-trichrome staining for forensic autopsy cases. Myocardium of left ventricle of 58 medicolegal autopsy cases, 12 OMI cases, 12 acute/OMI cases, and 34 control cases, were immunostained with anti-GAP-43 and anti-TH antibodies. Immunoreactivity of GAP-43 and TH identified nerve fibers and vascular wall in OMI cases and acute/OMI cases. Specifically, TH-positive nerve fibers were abundant at border zones of the infarcted site. There were a few GAP-43 and TH expressions in the control cases. With Masson-trichrome staining, collagen fibers were blue and cardiac muscle fibers were pink in marked contrast with the surrounding tissue, which improved the location of nerve fibers. Thus, these findings suggest that immunohistochemical detection of GAP-43 and TH combined with Masson-trichrome staining can provide the evidence for the medicolegal expertise of SCD due to OMI, and further demonstrate a close relationship between sympathetic hyperinnervation and SCD.

  18. Evaluation of general-purpose collimators against high-resolution collimators with resolution recovery with a view to reducing radiation dose in myocardial perfusion SPECT: A preliminary phantom study.

    Science.gov (United States)

    Armstrong, Ian S; Saint, Kimberley J; Tonge, Christine M; Arumugam, Parthiban

    2017-04-01

    There is a growing focus on reducing radiation dose to patients undergoing myocardial perfusion imaging. This preliminary phantom study aims to evaluate the use of general-purpose collimators with resolution recovery (RR) to allow a reduction in patient radiation dose. Images of a cardiac torso phantom with inferior and anterior wall defects were acquired on a GE Infinia and Siemens Symbia T6 using both high-resolution and general-purpose collimators. Imaging time, a surrogate for administered activity, was reduced between 35% and 40% with general-purpose collimators to match the counts acquired with high-resolution collimators. Images were reconstructed with RR with and without attenuation correction. Two pixel sizes were also investigated. Defect contrast was measured. Defect contrast on general-purpose images was superior or comparable to the high-resolution collimators on both systems despite the reduced imaging time. Infinia general-purpose images required a smaller pixel size to be used to maintain defect contrast, while Symbia T6 general-purpose images did not require a change in pixel size to that used for standard myocardial perfusion SPECT. This study suggests that general-purpose collimators with RR offer a potential for substantial dose reductions while providing similar or better image quality to images acquired using high-resolution collimators.

  19. One-year follow-up and convalescence evaluated by nuclear medicine studies and 24-hour holter electrocardiogram in 11 patients with myocardial injury due to a blunt chest trauma.

    Science.gov (United States)

    Amino, Mari; Yoshioka, Koichiro; Morita, Seiji; Iizuka, Shinichi; Otsuka, Hiroyuki; Yamamoto, Rie; Aoki, Hiromichi; Aizawa, Toru; Ikari, Yuji; Nasu, Seiji; Hatakeyama, Kenji; Iino, Misako; Kodama, Itsuo; Inokuchi, Sadaki; Tanabe, Teruhisa

    2009-05-01

    There are few reports on long-term convalescence with regard to cardiac injury caused by blunt chest trauma. Nuclear medicine study of the heart (NMSH) in the early stages of injury is reportedly superior to detect the correlation between injury and fatal arrhythmia. Therefore, we prospectively performed NMSH and Holter electrocardiogram (ECG) in the early and chronic stages for a cardiac injury patient, and we longitudinally examined the recovery process and the occurrence of fatal arrhythmia. A total of 202 patients with blunt chest trauma were admitted to our hospital between April 2006 and January 2007. Of 65 patients who were diagnosed with cardiac injury by ECG, a myocardial enzyme, or cardiac ultrasonography, 11 were enrolled in this study because they agreed to outpatient visiting for regular examinations for 1 year. NMSH showed positive findings in 6 of the 11 patients in the acute period of cardiac damage without complete recovery. Among the six patients in whom NMSH showed positive findings, Holter ECG indicated an abnormal finding in two patients in the acute period and in four patients in the chronic period, and detected one patient with a nonsustained ventricular tachycardia in the chronic period. Cardiac injuries may exacerbate cardiac functions and lead to fatal arrhythmia during the chronic period. Therefore, evaluating recovery for at least 12 months after myocardial damage is necessary to prevent sudden cardiac death.

  20. Anisotropy of the Topopah Spring Member Tuff

    Energy Technology Data Exchange (ETDEWEB)

    Martin, R.J. III; Boyd, P.J.; Haupt, R.W. [New England Research, Inc., White River Junction, VT (United States); Price, R.H. [Sandia National Labs., Albuquerque, NM (United States)

    1992-07-01

    Mechanical properties of the tuffaceous rocks within Yucca Mountain are needed for near and far-field modeling of the potential nuclear waste repository. If the mechanical properties are significantly anisotropic (i.e., direction-dependent), a more complex model is required. Relevant data from tuffs tested in earlier studies indicate that elastic and strength properties are anisotropic. This scoping study confirms the elastic anisotropy and concludes some tuffs are transversely isotropic. An approach for sampling and testing the rock to determine the magnitude of the anisotropy is proposed.

  1. Diffusion tensor imaging of normal white matter maturation from late childhood to young adulthood: voxel-wise evaluation of mean diffusivity, fractional anisotropy, radial and axial diffusivities, and correlation with reading development.

    Science.gov (United States)

    Qiu, Deqiang; Tan, Li-Hai; Zhou, Ke; Khong, Pek-Lan

    2008-06-01

    Using diffusion tensor MR imaging (DTI) and advanced voxel-wise analysis tools, we study diffusivity and anisotropy changes of white matter from late childhood to young adulthood, and correlate quantitative diffusion indices with Chinese and English reading performance scores. Seventy-five normal healthy school going ethnic Chinese students and young adults of three age groups were recruited (group 1, n=24, mean+/-SD=7.4+/-0.3 years; group 2, n=27, mean+/-SD=10.3+/-0.5 years; group 3, n=24, mean+/-SD=22.8+/-2.3 years). DTI was performed with 3 mm isotropic resolution to cover the entire brain. Voxel-wise analysis was performed using Tract-Based Spatial Statistics (TBSS) to localize regions of white matter showing significant changes of fractional anisotropy (FA), mean diffusivity (MD), and axial and radial diffusivities between groups. We found increased FA and decreased MD with increasing age in regions of cerebellar white matter, right temporal white matter, and a large portion of the superior frontal and parietal white matter driven by both the reduction of radial diffusivity and axial diffusivity with the former to a greater extent. Changes were continual from late childhood to young adulthood. Findings were confirmed by region-of-interest analysis in specific white matter tracts. After controlling for the effect of age, significant correlation was found between diffusion indices of the anterior limb of the left internal capsule and Chinese reading score (p=0.05), and of the corona radiata and English reading score (p=0.026 and p=0.029 for left and right, respectively). These DTI indices likely reflect the multiple biological processes that occur during brain development which provide the neural substrate for ongoing functional connectivity including for reading development.

  2. Myocardial infarction false alarm: initial electrocardiogram and cardiac enzymes.

    Science.gov (United States)

    Gupta, Esha Das; Sakthiswary, Rajalingham

    2014-05-01

    The objectives of this study were to determine the incidence of a myocardial infarction "false alarm" and evaluate the efficacy of the initial electrocardiogram and cardiac enzymes in diagnosing myocardial infarction in Malaysia. We recruited patients who were admitted with suspected myocardial infarction from June to August 2008. The medical records of these patients were reviewed for the initial electrocardiogram, initial cardiac enzyme levels (creatinine kinase-MB and troponin T), and the final diagnosis upon discharge. The subjects were stratified into 2 groups: true myocardial infarction, and false alarm. 125 patients were enrolled in this study. Following admission and further evaluation, the diagnosis was revised from myocardial infarction to other medical conditions in 48 (38.4%) patients. The sensitivity and specificity of the initial ischemic electrocardiographic changes were 54.5% and 70.8%, respectively. Raised cardiac enzymes had a sensitivity of 44.3% and specificity of 95.8%. A significant proportion of patients in Malaysia are admitted with a false-alarm myocardial infarction. The efficacy of the electrocardiogram in diagnosing myocardial infarction in Malaysia was comparable to the findings of Western studies, but the cardiac enzymes had a much lower sensitivity.

  3. Feasibility and Applicability of Computer-Assisted Myocardial Blush Quantification After Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction

    NARCIS (Netherlands)

    Haeck, Joost D. E.; Gu, Youlan L.; Vogelzang, Mathijs; Bilodeau, Luc; Krucoff, Mitchell W.; Tijssen, Jan G. P.; De Winter, Robbert J.; Zijlstra, Felix; Koch, Karel T.

    2010-01-01

    Objectives: The aim of the study was to evaluate whether the "Quantitative Blush Evaluator" (QuBE) score is associated with measures of myocardial reperfusion in patients with ST-segment elevation myocardial infarction (STEMI) treated in two hospitals with 24/7 coronary intervention facilities.

  4. Myocardial bridge of the anterior descending artery. Two case reports

    Directory of Open Access Journals (Sweden)

    Guillermo Adrián Rivera-Cardona

    2012-03-01

    Full Text Available The anterior descending artery (LAD is a branch of the left coronary artery (LCA, which supplies blood for left ventricle and septum. The coronary arteries and their branches have a subepicardical path; but, in this case it was observed a segment of the LAD with intramyocardial location which is called “Myocardial Bridge”. This finding was observed during dissection in hearts a 50 and 60 years old man, with antecedents of hypertension (HT. The clinical relevance of the myocardial bridges could be related with chest pain and myocardial alteration, which should be evaluated by coronary angiography.

  5. Nuclear myocardial perfusion imaging with a cadmium-telluride semiconductor detector gamma camera in patients with acute myocardial infarction.

    Science.gov (United States)

    Fukushima, Yoshimitsu; Kumita, Shin-ichiro; Kawaguchi, Tsuneaki; Maruyama, Takatoshi; Kawasaki, Yoshiyuki; Shinkai, Yasuhiro

    2014-08-01

    Since myocardial perfusion imaging (MPI) with conventional sodium iodine (NaI) device has low spatial resolution, there have been some cases in which small structures such as non-transmural myocardial infarction could not be properly detected. The purpose of this study was to evaluate potential usefulness of cadmium-telluride (CdTe) semiconductor detector-based high spatial resolution gamma cameras in detecting myocardial infarction sites, especially non-transmural infarction. A total of 38 patients (mean age ± SD: 64 ± 21 year) who were clinically diagnosed with acute myocardial infarction were included. Twenty-eight cases of them were with ST segment elevation myocardial infarction (STEMI) and 10 cases with non-ST segment elevation myocardial infarction (NSTEMI). In all patients, myocardial perfusion single photon emission computed tomography images were acquired with Infinia (NaI device) and R1-M (CdTe device), and the images were compared concerning the detectability of acute myocardial infarction sites. The detection rates of the myocardial infarction site in cases with STEMI were 100% both by NaI and CdTe images. In cases with NSTEMI, detection rate by NaI images was 50%, while that of CdTe images was 100% (p = 0.033). The summed rest score (SRS) value derived from CdTe images was significantly higher than that from NaI images in cases with STEMI [NaI images: 12 (7-18) versus CdTe images: 14 (9-20)] (p cases with NSTEMI [NaI images: 2 (0-5) versus CdTe images: 6 (6-8)] (p = 0.006). These results indicate that MPI using CdTe-semiconductor device will provide a much more accurate assessment of acute myocardial infarction in comparison to current methods.

  6. Effect of nicorandil on the myocardial tissue perfusion and myocardial cell injury in patients with diabetes after PCI

    Directory of Open Access Journals (Sweden)

    Xue-Li Ren1

    2017-04-01

    Full Text Available Objective: To study the effect of nicorandil on the myocardial tissue perfusion and myocardial cell damage in patients with diabetes after percutaneous coronary intervention (PCI. Methods: 68 patients with coronary heart disease and type 2 diabetes mellitus who received PCI in our hospital between May 2011 and September 2015 were collected and then divided into observation group and control group (n=34 according to the single-blind randomized control method. Control group of patients received PCI alone, and the observation group of patients received nicorandil therapy after PCI. After treatment, real-time myocardial ultrasound contrast was used to evaluate the myocardial perfusion of two groups of patients; blood biochemical analyzer was used to detect the contents of peripheral blood myocardial enzyme spectrum indexes; the ELISA method was used to detect the contents of serum oxidative stress indicators; RIA method was used to detect the contents of serum apoptosis molecules. Results: After treatment, the myocardial tissue perfusion parameters plateau peak intensity (A, slope rate of curve (β and myocardial blood flow (A×β levels of observation group were significantly higher than those of control group (P<0.05; peripheral blood myocardial enzyme spectrum indexes creatine kinase (CK, lactate dehydrogenase (LDH, troponin I (cTnI and glutamic oxalacetic transaminase (GOT contents of observation group were significantly lower than those of control group (P<0.05; serum vitamin E (VitE and vitamin C (VitC contents of observation group were significantly higher than those of control group while malondialdehyde (MDA, advanced oxidation protein products (AOPPs, soluble apoptosis-associated factor (sFas and soluble apoptosis-associated factor ligand (sFasL contents were lower than those of control group (P<0.05. Conclusion: Adjuvant nicorandil therapy can improve the myocardial perfusion and reduce the myocardial cell injury in patients with coronary

  7. Influence of the myocardial bridging phenomenon on the myocardial structure and the coronary arteries wall structure changes

    Directory of Open Access Journals (Sweden)

    Tomanović-Koković Jelena

    2006-01-01

    Full Text Available Background/Aim. Our research was performed to evaluate the influences of the myocardial bridging of coronary arteries on the myocardial and coronary arteries wall structure changes, that could be a reason for multiple heart malfunctions. Methods. We analyzed the autopsy material, collected during a five-years period, and especially the group of 575 cases with the major aim to diagnose mors naturalis. In all cases with the presence of myocardial bridge over the arterial coronary wall revealed at autopsy, samples were taken for microscopic verification and examination. Results. We found myocardial bridges over the coronary arteries or their major branches in 27 of the cases (4.70%. We believe that myocardial bridges compromise coronary perfusion by cyclic compression of the overbridged vessels, and that it could be the initial factor in the pathogenesis of arteriosclerotic degeneration processes on the coronary artery wall. We found different grades of arteriosclerotic changes in 88.89% of the cases, as well as fibrosis of myocardium in 88.89% and lipomatosis in 66.67% of the cases with the present myocardial bridges. Conclusion. Our results suggested that myocardial bridging of coronary arteries and/or their branches was the pathological and even lethal phenomenon that deserves more intensive clinical evaluation.

  8. The impact of acute myocardial infarction on left ventricular systolic function.

    Science.gov (United States)

    Koçinaj, Dardan; Bakalli, Aurora; Gashi, Masar; Begolli, Luljeta; Berisha, Merita; Koçinaj, Allma; Berisha, Blerim; Krasniqi, Xhevdet

    2011-01-01

    During acute myocardial infarction left ventricular systolic function is an important prognostic factor whose worsening is still frequent despite the therapeutic approach. We aimed to estimate the incidence of left ventricular systolic dysfunction among patients experiencing acute myocardial infarction. The study involved 154 consecutive patients admitted at Coronary Care Unit. The study design was based upon the collection of patient histories, clinical examination and other complementary tests. In overall study population, predominantly with male gender, the incidence of left ventricle systolic dysfunction was 42.3%, which correlated with myocardial damage, electrocardiography changes, myocardial enzymes, and myocardial wall motion. Transthoracic Echocardiography represents a valuable tool and left ventricular ejection fraction should be evaluated in all patients experiencing acute myocardial infarction since the incidence of left ventricular dysfunction in patients with Acute Myocardial Infarction remains relatively high.

  9. A quantitative histopathological study of right bundle branch block complicating acute anteroseptal myocardial infarction.

    OpenAIRE

    Okabe, M; Fukuda, K; Nakashima, Y; Hiroki, T; Arakawa, K; Kikuchi, M

    1991-01-01

    The aim of the present study was to evaluate whether necrosis of the right bundle branch is responsible for development of right bundle branch block in acute myocardial infarction. Twenty patients with acute anteroseptal myocardial infarction were studied--10 with right bundle branch block (group A) and 10 without (group B)--to evaluate by serial sectioning the pathological extent of myocardial infarction surrounding the right bundle branch and also that of right bundle branch necrosis. Myoca...

  10. Evaluation of the safety and efficacy of TY-51924 in patients with ST elevated acute myocardial infarction - Early phase II first in patient pilot study.

    Science.gov (United States)

    Takayama, Tadateru; Kimura, Kazuo; Fukuzawa, Shigeru; Hirayama, Haruo; Sone, Takahito; Ueda, Yasunori; Uematsu, Masaaki; Ishihara, Masaharu; Nakao, Koichi; Matsumoto, Naoya; Kosuge, Masami; Hiro, Takafumi; Asakura, Masanori; Kaneko, Akira; Yokoi, Toshiaki; Hirayama, Atsushi

    2016-02-01

    In myocardial ischemia-reperfusion injuries, the involvement of the Na(+)/H(+) exchanger (NHE) is considered to be one of the pathogenic mechanisms following reperfusion. TY-51924 is a novel hydrophilic NHE inhibitor with a lower risk of central neurotoxicity than previous NHE inhibitors. This open-label, dose-escalating study was undertaken to investigate the safety, efficacy, and pharmacokinetics of TY-51924 in patients with ST-elevation myocardial infarction (STEMI). Consent was obtained from a total of 30 patients with first anterior STEMI. After 12 patients were determined to be ineligible, the remaining 18 patients, each of whom was undergoing primary percutaneous coronary intervention (pPCI), received TY-51924 intravenously up to 10, 20, or 30mg/kg as the low-, medium-, or high-dose groups, respectively (n=6 in each group). The primary endpoints were safety (up to 7 days) and plasma drug concentration. The myocardial salvage index (MSI) was measured by (201)Tl/(123)I-beta-methyl-p-iodophenyl pentadecanoic acid single photon emission computed tomography (SPECT) 3-5 days after pPCI. No side effects were observed. Plasma drug concentrations increased dose-dependently, and were subsequently eliminated rapidly. MSIs were 0.118, 0.335, and 0.192 in the low-, medium-, and high-dose groups, respectively. In additional analysis, the combined MSIs in the medium- and high-dose groups were significantly higher than those in the low-dose group, in patients with a longer time from symptom onset to reperfusion (p=0.0247). No side effects were observed even at the highest dose with this novel hydrophilic NHE inhibitor. Therefore, TY-51924 is thought to be safe in patients with STEMI, even at the highest dose. Potential cardioprotective effects of intravenous TY-51924 might be expected based on the results obtained for the MSIs using SPECT at 20-30mg/kg. However, further large-scale, double-blind, placebo-controlled clinical studies are required to confirm the efficacy and

  11. Azimuthal anisotropy of jet quenching at LHC

    Indian Academy of Sciences (India)

    Abstract. We analyze the azimuthal anisotropy of jet spectra due to energy loss of hard partons in quark–gluon plasma, created initially in nuclear overlap zone in collisions with non-zero impact parameter. The calculations are performed for semi-central Pb–Pb collisions at LHC energy.

  12. Global anisotropy and the thickness of continents

    Science.gov (United States)

    Gung, Yuancheng; Panning, Mark; Romanowicz, Barbara

    2003-04-01

    For decades there has been a vigorous debate about the depth extent of continental roots. The analysis of heat-flow, mantle-xenolith and electrical-conductivity data all indicate that the coherent, conductive part of continental roots (the `tectosphere') is at most 200-250km thick. Some global seismic tomographic models agree with this estimate, but others suggest that a much thicker zone of high velocities lies beneath continental shields, reaching a depth of at least 400km. Here we show that this disagreement can be reconciled by taking into account seismic anisotropy. We show that significant radial anisotropy, with horizontally polarized shear waves travelling faster than those that are vertically polarized, is present under most cratons in the depth range 250-400km-similar to that found under ocean basins at shallower depths of 80-250km. We propose that, in both cases, the anisotropy is related to shear in a low-viscosity asthenospheric channel, located at different depths under continents and oceans. The seismically defined `tectosphere' is then at most 200-250km thick under old continents. The `Lehmann discontinuity', observed mostly under continents at about 200-250km, and the `Gutenberg discontinuity', observed under oceans at depths of about 60-80km, may both be associated with the bottom of the lithosphere, marking a transition to flow-induced asthenospheric anisotropy.

  13. Cosmology with cosmic microwave background anisotropy

    Indian Academy of Sciences (India)

    Measurements of CMB anisotropy and, more recently, polarization have played a very important role in allowing precise determination of various parameters of the `standard' cosmological model. The expectation of the paradigm of inflation and the generic prediction of the simplest realization of inflationary scenario in the ...

  14. Numerical likelihood analysis of cosmic ray anisotropies

    Energy Technology Data Exchange (ETDEWEB)

    Carlos Hojvat et al.

    2003-07-02

    A numerical likelihood approach to the determination of cosmic ray anisotropies is presented which offers many advantages over other approaches. It allows a wide range of statistically meaningful hypotheses to be compared even when full sky coverage is unavailable, can be readily extended in order to include measurement errors, and makes maximum unbiased use of all available information.

  15. Magnetic anisotropy in rare-earth metals

    DEFF Research Database (Denmark)

    Nielsen, Mourits; Bjerrum Møller, Hans; Lindgård, Per-Anker

    1970-01-01

    The magnetic field dependence of the energy of long- wavelength magnons in Tb-10%Ho has been studied by inelastic neutron scattering. The results agree with the `frozen-lattice' model, provided that the second-order magnetoelastic effect is taken into account. The planar anisotropy is almost enti...

  16. Effective anisotropy through traveltime and amplitude matching

    KAUST Repository

    Wang, Hui

    2014-08-05

    Introducing anisotropy to seismic wave propagation reveals more realistic physics of our Earth\\'s subsurface as compared to the isotropic assumption. However wavefield modeling, the engine of seismic inverse problems, in anisotropic media still suffers from computational burdens, in particular with complex anisotropy such as transversely isotropic (TI) and Orthorhombic anisotropy. We develop effective isotropic velocity and density models to package the effects of anisotropy such that the wave propagation behavior using these effective models approximate those of the original anisotropic model. We build these effective models through the high frequency asymptotic approximation based on the eikonal and transport equations. We match the geometrical behavior of the wave-fields, given by traveltimes, from the anisotropic and isotropic eikonal equations. This matching yields the effective isotropic velocity that approximates the kinematics of the anisotropic wavefield. Equivalently, we calculate the effective densities by equating the anisotropic and isotropic transport equations. The effective velocities and densities are then fed into the isotropic acoustic variable density wave equation to obtain cheaper anisotropic wavefields. We justify our approach by testing it on an elliptical anisotropic model. The numerical results demonstrate a good matching of both traveltime and amplitude between anisotropic and effective isotropic wavefields.

  17. Experimental investigation of ultrasonic velocity anisotropy in ...

    Indian Academy of Sciences (India)

    ... weak as the transverse component of the particle/cluster moment is larger than the longitudinal one and the system reaches saturation even at low field. These observed variations in the field-induced anisotropy are analysed by incorporating the moment distribution of particles in Tarapov's theory (J. Magn. Magn. Mater.

  18. What we learn from CMB Anisotropies

    CERN Multimedia

    CERN. Geneva

    2007-01-01

    George Smoot shared the 2006 Nobel Prize with John Mathere for the discovery of the fluctuations of the cosmic microwave background. In this talk (which will not be the same as the Nobel lecture), he will discuss what we have learned about the universe in the recent past from these anisotropies.

  19. Heterogeneity and anisotropy of Earth's inner core

    NARCIS (Netherlands)

    Deuss, Arwen|info:eu-repo/dai/nl/412396610

    2014-01-01

    Seismic observations provide strong evidence that Earth's inner core is anisotropic, with larger velocity in the polar than in the equatorial direction. The top 60-80 km of the inner core is isotropic; evidence for an innermost inner core is less compelling. The anisotropy is most likely due to

  20. Measurement of fission anisotropy for Ta

    Indian Academy of Sciences (India)

    It is shown that statistical transition state model (TSM) with pre-scission neutron correction described adequately the measured anisotropy data. Strong friction parameter is found to be necessary to estimate the pre-saddle to pre-scission neutron ratio. Keywords. Fusion–fssion; saddle-point model. PACS No. 25.70.Jj. 1.

  1. Anisotropy of Wood in the Microwave Region

    Science.gov (United States)

    Ziherl, Sasa; Bajc, Jurij; Urankar, Bernarda; Cepic, Mojca

    2010-01-01

    Wood is transparent for microwaves and due to its anisotropic structure has anisotropic dielectric properties. A laboratory experiment that allows for the qualitative demonstration and quantitative measurements of linear dichroism and birefringence in the microwave region is presented. As the proposed experiments are based on the anisotropy (of…

  2. Post-mortem cardiac diffusion tensor imaging: detection of myocardial infarction and remodeling of myofiber architecture.

    Science.gov (United States)

    Winklhofer, Sebastian; Stoeck, Christian T; Berger, Nicole; Thali, Michael; Manka, Robert; Kozerke, Sebastian; Alkadhi, Hatem; Stolzmann, Paul

    2014-11-01

    To investigate the accuracy of post-mortem diffusion tensor imaging (DTI) for the detection of myocardial infarction (MI) and to demonstrate the feasibility of helix angle (HA) calculation to study remodelling of myofibre architecture. Cardiac DTI was performed in 26 deceased subjects prior to autopsy for medicolegal reasons. Fractional anisotropy (FA) and mean diffusivity (MD) were determined. Accuracy was calculated on per-segment (AHA classification), per-territory, and per-patient basis, with pathology as reference standard. HAs were calculated and compared between healthy segments and those with MI. Autopsy demonstrated MI in 61/440 segments (13.9 %) in 12/26 deceased subjects. Healthy myocardial segments had significantly higher FA (p architecture, with significant differences between healthy segments and segments with chronic (p  0.05). Post-mortem cardiac DTI enables differentiation between healthy and infarcted myocardial segments by means of FA and MD. HA assessment allows for the demonstration of remodelling of myofibre architecture following chronic MI. • DTI enables post-mortem detection of myocardial infarction with good accuracy. • A decrease in right-handed helical fibre indicates myofibre remodelling following chronic myocardial infarction. • DTI allows for ruling out myocardial infarction by means of FA. • Post-mortem DTI may represent a valuable screening tool in forensic investigations.

  3. Electric field effect on magnetic anisotropy for Fe-Pt-Pd alloys

    Science.gov (United States)

    Kikushima, S.; Seki, T.; Uchida, K.; Saitoh, E.; Takanashi, K.

    2017-08-01

    The electric field effect on magnetic anisotropy was investigated for the FePt1-xPdx alloy films with perpendicular magnetic anisotropy. The polar magneto-optical Kerr (p-MOKE) loops were measured under the electric field application in order to evaluate the electric field-induced perpendicular magnetic anisotropy change per area (Δɛperpt). A clear change in the saturation field of p-MOKE loop was observed for FePt by varying the applied electric field (ΔE). In the case of FePt, Δɛperpt divided by ΔE was evaluated to be -129 (fJ/Vm). We found that the magnitude of Δɛperpt / ΔE was significantly reduced with increasing x.

  4. Electric field effect on magnetic anisotropy for Fe-Pt-Pd alloys

    Directory of Open Access Journals (Sweden)

    S. Kikushima

    2017-08-01

    Full Text Available The electric field effect on magnetic anisotropy was investigated for the FePt1-xPdx alloy films with perpendicular magnetic anisotropy. The polar magneto-optical Kerr (p-MOKE loops were measured under the electric field application in order to evaluate the electric field-induced perpendicular magnetic anisotropy change per area (Δεperpt. A clear change in the saturation field of p-MOKE loop was observed for FePt by varying the applied electric field (ΔE. In the case of FePt, Δεperpt divided by ΔE was evaluated to be -129 (fJ/Vm. We found that the magnitude of Δεperpt / ΔE was significantly reduced with increasing x.

  5. Effect of hydroxy safflower yellow A on myocardial apoptosis after acute myocardial infarction in rats.

    Science.gov (United States)

    Zhou, M X; Fu, J H; Zhang, Q; Wang, J Q

    2015-04-10

    This study aimed to investigate the effect of hydroxy safflower yellow A (HSYA) on myocardial apoptosis after acute myocardial infarction (AMI) in rats. We randomly divided 170 male Wistar rats into 6 groups (N = 23): normal control, sham, control, SY (90 mg/kg), HSYA high-dose (HSYA-H, 40 mg/kg), and HSYA low-dose groups (HSYA-L, 20 mg/kg). Myocardial ischemic injury was induced by ligating the anterior descending coronary artery, and the degree of myocardial ischemia was evaluated using electrocardiography and nitroblue tetrazolium staining. Bax and Bcl-2 expressions in the ischemic myocardium were determined using immunohistochemical analysis. Peroxisome proliferator-activated receptor-γ (PPAR-γ) expression in the myocardium of rats with AMI was determined using reverse transcription-polymerase chain reaction. Compared to rats in the control group, those in the HYSA-H, HSYA-L, and SY groups showed a decrease in the elevated ST segments and an increase in the infarct size. The rats in the drug-treated groups showed a significantly lower percentage of Bax-positive cells and a significantly higher percentage of Bcl-2-positive cells than those in the control group (P myocardial ischemia in rats, possibly by increasing the level of Bcl-2/Bax, and PPAR-γ may be not a necessary link in this process.

  6. [Acute myocardial infarction in patients under 45 years].

    Science.gov (United States)

    Morillas, Pedro J; Cabadés, Adolfo; Bertomeu, Vicente; Echanove, Ildefonso; Colomina, Francisco; Cebrián, Javier; Pérez, Gloria; Mota, Angel; Sánchez, Francisco Javier; Sanz, Juan Carlos

    2002-11-01

    To evaluate the differential features of acute myocardial infarction in patients younger than 45 years old compared to older patients. From 1995 to 1999, delays in the assistance, evaluation, and therapeutic strategies as well as complications in patients hospitalized with a diagnosis of acute myocardial infarction, have been registered in the intensive care units of the 17 hospitals participating in the PRIMVAC Register. During the study, 10,213 patients were registered, 6.8% younger than 45 years old (691 patients). Young patients show a greater prevalence of cigarette smoking (80.9 vs 34.1%; p digoxin, and inotropic drugs. Younger patients had a better prognosis and a lower mortality rate (3.5 vs 14%; p myocardial infarction in patients younger than 45 years had different clinical features and responded to different therapeutic and diagnostic approaches than acute myocardial infarction in patients over 45 years, as well as a better short-term prognosis.

  7. Tuning the Magnetic Anisotropy at a Molecule-Metal Interface

    DEFF Research Database (Denmark)

    Bairagi, K.; Bellec, A.; Repain, V.

    2015-01-01

    We demonstrate that a C60 overlayer enhances the perpendicular magnetic anisotropy of a Co thin film, inducing an inverse spin reorientation transition from in plane to out of plane. The driving force is the C60/Co interfacial magnetic anisotropy that we have measured quantitatively in situ......) surface decreases the perpendicular magnetic anisotropy. These results open the way to tailor the interfacial magnetic anisotropy in organic-material-ferromagnet systems....

  8. Phytochemical screening and evaluation of cardioprotective activity of ethanolic extract of Ocimum basilicum L. (basil) against isoproterenol induced myocardial infarction in rats

    Science.gov (United States)

    2012-01-01

    Background and the purpose of the study The objectives of the present study were phytochemical screening and study of the effects of ethanolic extract of aerial parts of Ocimum basilicum (basil) on cardiac functions and histopathological changes in isoproterenol-induced myocardial infarction (MI). Methods The leaves of the plant were extracted with ethanol by maceration and subjected to colorimetry to determine flavonoids and phenolic compounds. High-performance TLC analysis and subsequent CAMAG's TLC scanning were performed to quantify rosmarinic acid content. Wistar rats were assigned to 6 groups of normal control, sham, isoproterenol, and treatment with 10, 20, and 40 mg/kg of the extract two times per day concurrent with MI induction. A subcutaneous injection of isoproterenol (100 mg/kg/day) for 2 consecutive days was used to induce MI. Results Phytochemical screening indicated the presence of phenolic compounds (5.36%) and flavonoids (1.86%). Rosmarinic acid was the principal phenolic compound with a 15.74% existence. The ST-segment elevation induced by isoproterenol was significantly suppressed by all doses of the extract. A severe myocardial necrosis and fibrosis with a sharp reduction in left ventricular contractility and a marked increase in left ventricular end-diastolic pressure were seen in the isoproterenol group, all of which were significantly improved by the extract treatment. In addition to in-vitro antioxidant activity, the extract significantly suppressed the elevation of malondialdehyde levels both in the serum and the myocardium. Conclusion The results of the study demonstrate that Ocimum basilicum strongly protected the myocardium against isoproterenol-induced infarction and suggest that the cardioprotective effects could be related to antioxidative activities. PMID:23351503

  9. Phytochemical Screening and Evaluation of Cardioprotective Activity of Ethanolic Extract of Ocimum Basilicum L. (Basil Against Isoproterenol Induced Myocardial Infarction in Rats

    Directory of Open Access Journals (Sweden)

    Hamid Soraya

    2012-01-01

    Full Text Available Background and the purpose of the study: The objectives of the present study were phytochemical screening and study of the effects of ethanolic extract of aerial parts of Ocimum basilicum (basil on cardiac functions and histopathological changes in isoproterenol-induced myocardial infarction (MI.Methods: The leaves of the plant were extracted with ethanol by maceration and subjected to colorimetry to determine flavonoids and phenolic compounds. High-performance TLC analysis and subsequent CAMAG's TLC scanning were performed to quantify rosmarinic acid content. Wistar rats were assigned to 6 groups of normalcontrol, sham, isoproterenol, and treatment with 10, 20, and 40 mg/kg of the extract two times per day concurrent with MI induction. A subcutaneous injection of isoproterenol (100 mg/kg/day for 2 consecutive days was used to induce MI.Results: Phytochemical screening indicated the presence of phenolic compounds (5.36% and flavonoids (1.86%.Rosmarinic acid was the principal phenolic compound with a 15.74% existence. The ST-segment elevation induced by isoproterenol was significantly suppressed by all doses of the extract. A severe myocardial necrosis and fibrosis with a sharp reduction in left ventricular contractility and a marked increase in left ventricular end-diastolic pressure were seen in the isoproterenol group, all of which were significantly improved by the extract treatment. In addition to in-vitro antioxidant activity, the extract significantly suppressed the elevation of malondialdehyde levels both inthe serum and the myocardium.Conclusion: The results of the study demonstrate that Ocimum basilicum strongly protected the myocardium against isoproterenol-induced infarction and suggest that the cardioprotective effects could be related to antioxidative activities.

  10. Preclinical Evaluation of the Engineered Stem Cell Chemokine Stromal Cell-Derived Factor 1–alpha Analogue in a Translational Ovine Myocardial Infarction Model

    Science.gov (United States)

    MacArthur, John W.; Cohen, Jeffrey E.; McGarvey, Jeremy R.; Shudo, Yasuhiro; Patel, Jay B.; Trubelja, Alen; Fairman, Alexander S.; Edwards, Bryan B.; Hung, George; Hiesinger, William; Goldstone, Andrew B.; Atluri, Pavan; Wilensky, Robert L.; Pilla, James J.; Gorman, Joseph H.; Gorman, Robert C.; Woo, Y. Joseph

    2014-01-01

    Rationale Following myocardial infarction (MI) there is an inadequate blood supply to the myocardium and the surrounding borderzone becomes hypocontractile. Objective To develop a clinically translatable therapy, we hypothesized that in a preclinical ovine model of MI, the modified endothelial progenitor stem cell (EPC) chemokine, engineered stromal cell-derived factor 1-alpha analogue (ESA), would induce EPC chemotaxis, limit adverse ventricular remodeling, and preserve borderzone contractility. Methods and Results Thirty six adult male Dorset sheep underwent permanent ligation of the left anterior descending coronary artery, inducing an anteroapical infarction and were randomized to borderzone injection of saline (n=18) or ESA (n=18). Ventricular function, geometry, and regional strain were assessed using cardiac magnetic resonance imaging and pressure-volume catheter transduction. Bone marrow was harvested for in-vitro analysis, and myocardial biopsies were taken for mRNA, protein and immunohistochemical analysis. ESA induced greater chemotaxis of EPCs compared to saline (p<0.01), and was equivalent to recombinant stromal cell-derived factor 1-alpha (p=0.27). Analysis of mRNA expression and protein levels in ESA treated animals revealed reduced MMP-2 in the borderzone (p<0.05), with elevated levels of TIMP-1 and elastin in the infarct (p<0.05), while immunohistochemical analysis of borderzone myocardium showed increased capillary and arteriolar density in the ESA group (p<0.01). Animals in the ESA treatment group also had significant reductions in infarct size (p<0.01), increased maximal principle strain in the borderzone (p<0.01), and a steeper slope of the end systolic pressure volume relationship (p=0.01). Conclusions The novel, biomolecularly-designed peptide ESA induces chemotaxis of EPCs, stimulates neovasculogenesis, limits infarct expansion, and preserves contractility in an ovine model of MI. PMID:24366171

  11. Phytochemical screening and evaluation of cardioprotective activity of ethanolic extract of Ocimum basilicum L. (basil against isoproterenol induced myocardial infarction in rats

    Directory of Open Access Journals (Sweden)

    Fathiazad Fatemeh

    2012-12-01

    Full Text Available Abstract Background and the purpose of the study The objectives of the present study were phytochemical screening and study of the effects of ethanolic extract of aerial parts of Ocimum basilicum (basil on cardiac functions and histopathological changes in isoproterenol-induced myocardial infarction (MI. Methods The leaves of the plant were extracted with ethanol by maceration and subjected to colorimetry to determine flavonoids and phenolic compounds. High-performance TLC analysis and subsequent CAMAG's TLC scanning were performed to quantify rosmarinic acid content. Wistar rats were assigned to 6 groups of normal control, sham, isoproterenol, and treatment with 10, 20, and 40 mg/kg of the extract two times per day concurrent with MI induction. A subcutaneous injection of isoproterenol (100 mg/kg/day for 2 consecutive days was used to induce MI. Results Phytochemical screening indicated the presence of phenolic compounds (5.36% and flavonoids (1.86%. Rosmarinic acid was the principal phenolic compound with a 15.74% existence. The ST-segment elevation induced by isoproterenol was significantly suppressed by all doses of the extract. A severe myocardial necrosis and fibrosis with a sharp reduction in left ventricular contractility and a marked increase in left ventricular end-diastolic pressure were seen in the isoproterenol group, all of which were significantly improved by the extract treatment. In addition to in-vitro antioxidant activity, the extract significantly suppressed the elevation of malondialdehyde levels both in the serum and the myocardium. Conclusion The results of the study demonstrate that Ocimum basilicum strongly protected the myocardium against isoproterenol-induced infarction and suggest that the cardioprotective effects could be related to antioxidative activities.

  12. Evaluation of Right Ventricular Myocardial Mechanics Using Velocity Vector Imaging of Cardiac MRI Cine Images in Transposition of the Great Arteries Following Atrial and Arterial Switch Operations.

    Science.gov (United States)

    Thattaliyath, Bijoy D; Forsha, Daniel E; Stewart, Chad; Barker, Piers C A; Campbell, Michael J

    2015-01-01

    The aim of the study was to determine right and left ventricle deformation parameters in patients with transposition of the great arteries who had undergone atrial or arterial switch procedures. Patients with transposition are born with a systemic right ventricle. Historically, the atrial switch operation, in which the right ventricle remains the systemic ventricle, was performed. These patients have increased rates of morbidity and mortality. We used cardiac MRI with Velocity Vector Imaging analysis to characterize and compare ventricular myocardial deformation in patients who had an atrial switch or arterial switch operation. Patients with a history of these procedures, who had a clinically ordered cardiac MRI were included in the study. Consecutive 20 patients (75% male, 28.7 ± 1.8 years) who underwent atrial switch operation and 20 patients (60% male, 17.7 ± 1.9 years) who underwent arterial switch operation were included in the study. Four chamber and short-axis cine images were used to determine longitudinal and circumferential strain and strain rate using Vector Velocity Imaging software. Compared with the arterial switch group, the atrial switch group had decreased right ventricular ejection fraction and increased end-diastolic and end-systolic volumes, and no difference in left ventricular ejection fraction and volumes. The atrial switch group had decreased longitudinal and circumferential strain and strain rate. When compared with normal controls multiple strain parameters in the atrial switch group were reduced. Myocardial deformation analysis of transposition patients reveals a reduction of right ventricular function and decreased longitudinal and circumferential strain parameters in patients with an atrial switch operation compared with those with arterial switch operation. A better understanding of the mechanisms of right ventricle failure in transposition of great arteries may lead to improved therapies and adaptation. © 2015 Wiley Periodicals

  13. Synthetic seismic anisotropy models within a slab impinging on the core-mantle boundary

    Science.gov (United States)

    Cottaar, Sanne; Li, Mingming; McNamara, Allen K.; Romanowicz, Barbara; Wenk, Hans-Rudolf

    2014-10-01

    The lowermost few hundreds of kilometres of the Earth's mantle are elastically anisotropic; seismic velocities vary with direction of propagation and polarization. Observations of strong seismic anisotropy correlate with regions where subducted slab material is expected. In this study, we evaluate the hypothesis that crystal preferred orientation (CPO) in a slab, as it impinges on the core-mantle boundary, is the cause of the observed anisotropy. Next, we determine if fast polarization directions seen by shear waves can be mapped to directions of geodynamic flow. This approach is similar to our previous study performed for a 2-D geodynamic model. In this study, we employ a 3-D geodynamic model with temperature-dependent viscosity and kinematic velocity boundary conditions defined at the surface of the Earth to create a broad downwelling slab. Tracers track the deformation that we assume to be accommodated by dislocation creep. We evaluate the models for the presence of perovskite or post-perovskite and for different main slip systems along which dislocation creep may occur in post-perovskite [(100),(010) and (001)]-resulting in four different mineralogical models of CPO. Combining the crystal pole orientations with single crystal elastic constants results in seismically distinguishable models of seismic anisotropy. The models are evaluated against published seismic observations by analysing different anisotropic components: the radial anisotropy, the splitting for (sub-)vertical phases (i.e. azimuthal anisotropy), and the splitting for subhorizontal phases. The patterns in radial anisotropy confirm our earlier results in 2-D. Observations of radial anisotropy and splitting in subhorizontal phases are mostly consistent with our models of post-perovskite with (010)-slip and (001)-slip. Our model of (001)-slip predicts stronger splitting than for (010)-slip for horizontally propagating phases in all directions. The strongest seismic anisotropy in this model occurs

  14. Correlation between reverse redistribution and subendocardial myocardial infarction observed in myocardial contrast echocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Eun; Choe, Won Sick; Kwan, Jun [Inha Univ. Hospital, Inchon (Korea, Republic of)

    2000-06-01

    The aim of this study is to better understand the pattern and nature of reverse redistribution (RR) in myocardial perfusion imaging. In consecutive 20 acute myocardial infarction (MI) patients, frequency of RR was correlated with that of subendocardial MI that was detected by myocardial contrast echocardiography (MCE). RR was judged to be present when there was more than one grade of worsening in perfusion at 24 hr delayed images compared with the initial rest images. MCE evaluated the significant lack of opacification in the subendocardial myocardium relative to the subepicardial myocardium to suggest the subendocardial MI. Kendall's nonparametric correlation coefficiency was calculated. Concordant cases were 15 of 20 (75%) and correlation was statistically significant (p=3D0.0285). Our results suggested that RR was correlated with MCE-detected nontransmural MI.

  15. Effect of thrombolytic therapy on postinfarction myocardial ischemia

    DEFF Research Database (Denmark)

    Mickley, H; Junker, A; Møller, M

    1994-01-01

    In patients with acute myocardial infarction a substantial reduction in mortality can be achieved by early intravenous thrombolytic therapy. The beneficial effect of thrombolysis on left ventricular function is relatively small, and it seems unlikely that this minor improvement alone can...... be responsible for the reduction in cardiac death. So far it has not been clearly established how thrombolytic therapy affects postinfarction myocardial ischemia. From studies evaluating ST segment changes on exercise testing or ambulatory monitoring it is concluded that thrombolysis probably results...

  16. What does anisotropy measure? Insights from increased and decreased anisotropy in selective fiber tracts in schizophrenia.

    Directory of Open Access Journals (Sweden)

    Gabriel A De Erausquin

    2013-03-01

    Full Text Available Schizophrenia is a common, severe and chronically disabling mental illness of unknown cause. Recent MRI studies have focused attention on white matter abnormalities in schizophrenia using diffusion tensor imaging (DTI. Indices commonly derived from DTI include (a mean diffusivity, independent of direction, (b fractional anisotropy (FA or relative anisotropy (RA, (c axial diffusivity, and (d radial diffusivity. In cerebral white matter, contributions to these indices come from fiber arrangements, degree of myelination, and axonal integrity. Relatively pure deficits in myelin result in a modest increase in radial diffusivity, without affecting axial diffusivity and with preservation of anisotropy. Although schizophrenia is not characterized by gross abnormalities of white matter, it does involve a profound dysregulation of myelin-associated gene expression, reductions in oligodendrocyte numbers, and marked abnormalities in the ultrastructure of myelin sheaths. Since each oligodendrocyte myelinates as many as 40 axon segments, changes in the number of oligodendrocytes, and/or in the integrity of myelin sheaths, and/or axoglial contacts can have a profound impact on signal propagation and the integrity of neuronal circuits. Whereas a number of studies have revealed inconsistent decreases in anisotropy in schizophrenia, we and others have found increased fractional anisotropy in key subcortical tracts associated with the circuits underlying symptom generation in schizophrenia. We review data revealing increased anisotropy in dopaminergic tracts in the mesencephalon of schizophrenics and their unaffected relatives, and discuss the possible biological underpinnings and physiological significance of this finding.

  17. [Bonsai induced acute myocardial infarction].

    Science.gov (United States)

    Ayhan, Hüseyin; Aslan, Abdullah Nabi; Süygün, Hakan; Durmaz, Tahir

    2014-09-01

    Incidences of drug abuse and cannabis have increased in young adults, recently. Cannabis induced myocardial infarction has rarely been reported in these people. There is no any literature about a synthetic cannabinoid, being recently most popular Bonsai, to cause myocardial infarction. In this case report we presented a 33-year-old male patient who developed acute myocardial infarction after taking high doses of Bonsai.

  18. Mean platelet volume is associated with poor postinterventional myocardial blush grade in patients with ST-segment elevation myocardial infarction.

    Science.gov (United States)

    Sarli, Bahadir; Baktir, Ahmet O; Saglam, Hayrettin; Arinc, Huseyin; Kurtul, Serkan; Sivgin, Serdar; Akpek, Mahmut; Kaya, Mehmet G

    2013-06-01

    In a significant proportion of patients with ST-elevation myocardial infarction (STEMI), microvascular and myocardial reperfusion cannot be regained despite successfully restored thrombolysis in myocardial infarction (TIMI) grade 3 epicardial blood flow. Myocardial blush grade (MBG) is a reliable marker for microvascular patency and predicts short-term and long-term mortality after primary percutaneous coronary intervention (PCI) in patients with acute STEMI, independent of other variables. Mean platelet volume (MPV), a unique measure of platelet size, is an indicator of platelet reactivity. In this study, we aimed to investigate the relation of admission MPV with postinterventional MBG in patients with STEMI and TIMI grade 3 flow at infarct artery after primary PCI. Three hundred and ten patients were selected as a study group among patients with STEMI and TIMI grade 3 epicardial blood flow after primary PCI. Blood samples for analysis were obtained during the initial evaluation of patients at the emergency department. MBGs of patients were classified at the end of angioplasty. Patients with MBG 0 and 1 were defined as having poor myocardial blush and patients with MBG 2 and 3 were defined as having normal myocardial blush. Patients with poor myocardial blush had higher admission MPV (10.5±1.3 to 9.1±1 fl, Padmission MPV was significantly associated with postinterventional MBG (coefficient=0.598, Padmission is significantly associated with poor postinterventional MBG in patients with STEMI and TIMI grade 3 flow at infarct artery after primary PCI.

  19. Anisotropy of strength and deformability of fractured rocks

    Directory of Open Access Journals (Sweden)

    Majid Noorian Bidgoli

    2014-04-01

    Full Text Available Anisotropy of the strength and deformation behaviors of fractured rock masses is a crucial issue for design and stability assessments of rock engineering structures, due mainly to the non-uniform and non-regular geometries of the fracture systems. However, no adequate efforts have been made to study this issue due to the current practical impossibility of laboratory tests with samples of large volumes containing many fractures, and the difficulty for controlling reliable initial and boundary conditions for large-scale in situ tests. Therefore, a reliable numerical predicting approach for evaluating anisotropy of fractured rock masses is needed. The objective of this study is to systematically investigate anisotropy of strength and deformability of fractured rocks, which has not been conducted in the past, using a numerical modeling method. A series of realistic two-dimensional (2D discrete fracture network (DFN models were established based on site investigation data, which were then loaded in different directions, using the code UDEC of discrete element method (DEM, with changing confining pressures. Numerical results show that strength envelopes and elastic deformability parameters of tested numerical models are significantly anisotropic, and vary with changing axial loading and confining pressures. The results indicate that for design and safety assessments of rock engineering projects, the directional variations of strength and deformability of the fractured rock mass concerned must be treated properly with respect to the directions of in situ stresses. Traditional practice for simply positioning axial orientation of tunnels in association with principal stress directions only may not be adequate for safety requirements. Outstanding issues of the present study and suggestions for future study are also presented.

  20. Effects of angiotensin-converting enzyme inhibition and bradykinin peptides in rats with myocardial infarction.

    Science.gov (United States)

    Qu, Zhe; Xu, Hongxin; Tian, Yihao

    2015-01-01

    Angiotensin-converting enzyme (ACE) inhibitors have been reported to decrease myocardial remodeling and faciliate cardiac function improvement in the setting myocardial infarction by affecting bradykinin. The purpose of this study was to evaluate the combination effects of perindopril and bradykinin (BK) in rats with myocardial infarction. Wistar Rats underwent to left anterior descending (LAD) coronary artery ligation were allocated into MI group (n=6); Perindopril group (n=7); Perindopril+BK group (n=7). An additional sham operation group (Sham group, n=6) were also established. After 4 weeks, the left ventricle function, myocardial tissue morphology, myocardial collagen volume faction, infracted ventricular wall thickness, myocardial infarction area and neovascular formation were evaluated. Combination treatment with perindopril and BK were showed significant improvement on LVEDV, LVEF and LVFS than MI group. Moreover, a significant improvement on LVEF was found in Perindopril+BK group than Perindopril group but not on LVEDV and LVFS between these two groups. Furthermore, neo-vessel density was significantly increased in Perindopril+BK group than other groups while no significant improvement on vessel density was found after the treatment of perindopril. In addition, myocardial infarction thickness improvement was found in Perindopril and group than MI group while combination treatment with perindopril and BK can significant improve the myocardial infarction thickness than perindopril only. Combination treatment with ACE inhibitor perindopril and BK can significantly improve the ventricle function in the rat model of myocardial infarction. Our data suggest BK can serve as adjuvant treatment in myocardial infarction treatment.

  1. Evaluation of endothelium-dependent myocardial perfusion reserve in healthy smokers; cold pressor test using H{sub 2}{sup 15}O PET

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Kyung Hoon [School of Medicine, Gachon Univ., Incheon (Korea, Republic of); Lee, Dong Soo; Lee, Byeong Il; Lee, Jae Sung; Lee, Ho Young; Chung, June Key; Lee, Myung Chul [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    2004-02-01

    Much evidence suggests long-term cigarette smoking alters coronary vascular endothelial response. In this study, we applied nonnegative matrix factorization (NMF), an unsupervised learning algorithm, to CO-less H{sub 2}{sup 15}O-PET to investigate coronary endothelial dysfunction caused by smoking noninvasively. This study enrolled eighteen young male volunteers consisting of 9 smokers (23.8{+-}1.1 yr; 6.6{+-}2.5 pack-years) and 9 nonsmokers (23.8{+-}2.9 yr). They do not have any cardiovascular risk factor or disease history. Myocardial H{sub 2}{sup 15}O-PET was performed at rest, during cold (5.deg.C) pressor stimulation and during adenosine infusion. Left ventricular blood pool and myocardium were segmented on dynamic PET data by NMF method. Myocardial blood flow (MBF) was calculated from input and tissue functions by a single compartmental model with correction of partial volume and spillover effects. There were no significant difference in resting MBF between the two groups (Smokers: 1.43 0.41ml/g/min and non-smokers: 1.37{+-}0.41 ml/g/min; p = NS). during cold pressor stimulation, MBF in smokers was significantly lower than that in non-smokers (1.25{+-}0.34 ml/g/min vs 1.59{+-}0.29 ml/g/min ; p = 0.019). The difference in the ratio of cold pressor MBF to resting MBF between the two groups was also significant (p=0.024; 90{+-}24% in smokers and 122{+-}28% in non-smokers.). During adenosine infusion, however, hyperemic MBF did not differ significantly between smokers and non-smokers (5.81{+-}1.99 ml/g/min vs 5.11{+-}1.31 ml/g/min ; p=NS). In smokers, MBF during cold pressor stimulation was significantly lower compared with nonsmokers, reflecting smoking-induced endothelial dysfunction. However, there was no significant difference in MBF during adenosine-induced hyperemia between the two groups.

  2. Perpendicular magnetic anisotropy of two-dimensional Rashba ferromagnets

    Science.gov (United States)

    Kim, Kyoung-Whan; Lee, Kyung-Jin; Lee, Hyun-Woo; Stiles, M. D.

    2017-01-01

    We compute the magnetocrystalline anisotropy energy within two-dimensional Rashba models. For a ferromagnetic free-electron Rashba model, the magnetic anisotropy is exactly zero regardless of the strength of the Rashba coupling, unless only the lowest band is occupied. For this latter case, the model predicts in-plane anisotropy. For a more realistic Rashba model with finite band width, the magnetic anisotropy evolves from in-plane to perpendicular and back to in-plane as bands are progressively filled. This evolution agrees with first-principles calculations on the interfacial anisotropy, suggesting that the Rashba model captures energetics leading to anisotropy originating from the interface provided that the model takes account of the finite Brillouin zone. The results show that the electron density modulation by doping or an external voltage is more important for voltage-controlled magnetic anisotropy than the modulation of the Rashba parameter. PMID:28596998

  3. Using Resistivity Measurements to Determine Anisotropy in Soil and Weathered Rock

    Directory of Open Access Journals (Sweden)

    S. Soto-Caban

    2013-08-01

    Full Text Available This study uses electrical resistivity measurements of soils and weathered rock to perform a fast and reliable evaluation of field anisotropy. Two test sites at New Concord, Ohio were used for the study. These sites are characterized by different landform and slightly east dipping limestone and siltstone formations of Pennsylvanian age. The measured resistivity ranged from 19 Ω∙m to 100 ��∙m, and varied with depth, landform, and season. The anisotropy was determined by a comparison of resistance values along the directions of strike and the dip. Measurements showed that the orientation of electrical anisotropy in the shallow ground may vary due to fluid connection, which is determined by the pore geometry in soil and rock, as well as by the direction of fluid movement. Results from this study indicated that a portable electrical resistivity meter is sensitive and reliable enough to be used for shallow ground fluid monitoring.

  4. ST segment elevations: Always a marker of acute myocardial infarction?

    Directory of Open Access Journals (Sweden)

    G. Coppola

    2013-07-01

    Full Text Available Chest pain is one of the chief presenting complaints among patients attending Emergency department. The diagnosis of acute myocardial infarction may be a challenge. Various tools such as anamnesis, blood sample (with evaluation of markers of myocardial necrosis, ultrasound techniques and coronary computed tomography could be useful. However, the interpretation of electrocardiograms of these patients may be a real concern. The earliest manifestations of myocardial ischemia typically interest T waves and ST segment. Despite the high sensitivity, ST segment deviation has however poor specificity since it may be observed in many other cardiac and non-cardiac conditions. Therefore, when ST–T abnormalities are detected the physicians should take into account many other parameters (such as risk factors, symptoms and anamnesis and all the other differential diagnoses. The aim of our review is to overview of the main conditions that may mimic a ST segment Elevation Myocardial Infarction (STEMI.

  5. Copeptin Testing in Acute Myocardial Infarction: Ready for Routine Use?

    Science.gov (United States)

    Reinstadler, Sebastian Johannes; Klug, Gert; Metzler, Bernhard; Mair, Johannes

    2015-01-01

    Suspected acute myocardial infarction is one of the leading causes of admission to emergency departments. In the last decade, biomarkers revolutionized the management of patients with suspected acute coronary syndromes. Besides their pivotal assistance in timely diagnosis, biomarkers provide additional information for risk stratification. Cardiac troponins I and T are the most sensitive and specific markers of acute myocardial injury. Nonetheless, in order to overcome the remaining limitations of these markers, novel candidate biomarkers sensitive to early stage of disease are being extensively investigated. Among them, copeptin, a stable peptide derived from the precursor of vasopressin, emerged as a promising biomarker for the evaluation of suspected acute myocardial infarction. In this review, we summarize the currently available evidence for the usefulness of copeptin in the diagnosis and risk stratification of patients with suspected acute myocardial infarction in comparison with routine biomarkers. PMID:25960596

  6. Copeptin Testing in Acute Myocardial Infarction: Ready for Routine Use?

    Directory of Open Access Journals (Sweden)

    Sebastian Johannes Reinstadler

    2015-01-01

    Full Text Available Suspected acute myocardial infarction is one of the leading causes of admission to emergency departments. In the last decade, biomarkers revolutionized the management of patients with suspected acute coronary syndromes. Besides their pivotal assistance in timely diagnosis, biomarkers provide additional information for risk stratification. Cardiac troponins I and T are the most sensitive and specific markers of acute myocardial injury. Nonetheless, in order to overcome the remaining limitations of these markers, novel candidate biomarkers sensitive to early stage of disease are being extensively investigated. Among them, copeptin, a stable peptide derived from the precursor of vasopressin, emerged as a promising biomarker for the evaluation of suspected acute myocardial infarction. In this review, we summarize the currently available evidence for the usefulness of copeptin in the diagnosis and risk stratification of patients with suspected acute myocardial infarction in comparison with routine biomarkers.

  7. Intracoronary and systemic melatonin to patients with acute myocardial infarction

    DEFF Research Database (Denmark)

    Halladin, Natalie L; Busch, Sarah Ekeløf; Jensen, Svend Eggert

    2014-01-01

    INTRODUCTION: Ischaemia-reperfusion injury following acute myocardial infarctions (AMI) is an unavoidable consequence of the primary percutaneous coronary intervention (pPCI) procedure. A pivotal mechanism in ischaemia-reperfusion injury is the production of reactive oxygen species following...... following pPCI in patients with AMI. MATERIAL AND METHODS: The IMPACT trial is a multicentre, randomised, double-blinded, placebo-controlled study. We wish to include 2 × 20 patients with ST-elevation myocardial infarctions undergoing pPCI within six hours from symptom onset. The primary end......-point is the Myocardial Salvage Index assessed by cardiovascular magnetic resonance imaging on day 4 (± 1) after pPCI. The secondary end-points are high-sensitivity troponin, creatinekinase myocardial band and clinical events. CONCLUSION: The aim of the IMPACT trial is to evaluate the effect of melatonin on reperfusion...

  8. A Case of Myopericarditis Mimicking Acute Myocardial Infarction in Childhood

    Directory of Open Access Journals (Sweden)

    Rahmi Özdemir

    2015-11-01

    Full Text Available Myopericarditis is an inflammatory disease of the both myocardial and pericardial tissues, and resulting from different etiologies. Viral agents such as coxsackie virus type B, adenovirus, and echovirus are the most common leading cause of this disease and it usually occurs following viral upper respiratory tract infections. Although there are different clinical features according to ages groups, some common findings such as tachycardia incompatible with fever, deeply heared heart sounds, and heart failure can be seen. Clinical findings often mimics a myocardial infarction. Diagnosis of this disease is made by the evaluation of the clinical condition, electrocardiography, echocardiography and elevation of the cardiac enzymes. Because it is mortality, discrimination of myopericarditis from myocardial infarction is very important. Herein, we report a 13 year-old-girl with the diagnosis of myopericarditis presenting with chest pain, electrocardiographic changes mimicking myocardial infarction and elevated cardiac enzymes and also aimed to emphasize the importance of accurate diagnosis of this disease.

  9. Microstructure anisotropy in polyolefin flexible foams

    Energy Technology Data Exchange (ETDEWEB)

    Antunes, M; Arencon, D; Realinho, V [Centre Catala del Plastic, Departament de Ciencia dels Materials i Enginyeria Metallurgica, Universitat Politecnica de Catalunya, C/Colom 114. E-08222 Terrassa, Barcelona (Spain); Velasco, J I, E-mail: jose.ignacio.velasco@upc.edu

    2009-09-15

    The use of polyolefin flexible foams with typical thicknesses between 1 and 3 mm produced by a physical foaming extrusion process is nowadays quite widespread in the packaging sector. Their high flexibility and closed-cell structure allows them to show good energy absorption properties under low loading conditions. Although the compressive response of these materials is well known, the inner microstructure developed during processing induce a high anisotropy that is responsible for their direction-dependent tensile and fracture behaviours. In this work, two different polyolefin-based foams, with densities ranging from 20 to 45 kg/m{sup 3}, were studied. The induced microstructure anisotropy was characterized by micro-Raman. With this technique, the relative orientations of both crystalline and amorphous phases in the foam's base polymer could be determined and thus related to their mechanical properties measured in the different directions.

  10. Primordial anisotropies from cosmic strings during inflation

    Science.gov (United States)

    Jazayeri, Sadra; Sadr, Alireza Vafaei; Firouzjahi, Hassan

    2017-07-01

    In this work, we study the imprint of an individual primordial cosmic string within a Hubble patch on the inflationary power spectrum. A straight cosmic string induces two distinct contributions to the curvature perturbations power spectrum. The first type of correction respects the translation invariance while violating isotropy. This generates quadrupolar statistical anisotropy in cosmic microwave background maps, which is constrained by the Planck data. The second contribution breaks both homogeneity and isotropy, generating a dipolar power asymmetry in the variance of temperature fluctuations with its amplitude falling on small scales. We show that the strongest constraint on the tension of primordial cosmic strings is obtained from the quadrupolar anisotropy and argue that the mass scale of the underlying theory responsible for the formation of the string cannot be much higher than the grand unified theory scale. The predictions for the diagonal and off-diagonal components of the cosmic microwave background angular power spectrum induced by the string are presented.

  11. Time-to-treatment significantly affects the extent of ST-segment resolution and myocardial blush in patients with acute myocardial infarction treated by primary angioplasty

    NARCIS (Netherlands)

    De Luca, G.; van't Hof, A.W.J.; de Boer, M.J.; Ottervanger, J.P.; Hoorntje, J.C.A.; Gosselink, A.T.M.; Dambrink, J.H.E.; Zijlstra, F.; Suryapranata, H.

    2004-01-01

    Aims The prognostic role of time-to-treatment in primary angioplasty is still a matter of debate. The aim of our study was to evaluate the relationship between time-to-treatment and myocardial perfusion in patients with ST-segment-elevation myocardial infarction (STEMI) treated by primary

  12. Multi-center randomized trial on the impact of “CONFIDENCE” communication program aimed at evaluating therapy adherence of patients with registered myocardial infarction who underwent successful revascularization by stenting or thrombolysis after discharg

    Directory of Open Access Journals (Sweden)

    А. Р. Таркова

    2017-04-01

    Full Text Available Aim. The article looks at the effect of the program "Confidence" to increase the proportion of patients’ therapy in patients with coronary heart disease for two years after successful revascularization using thrombolytic or stenting of the coronary arteries on the myocardial infarction.Methods. This is a prospective, randomized, controlled, parallel-group trial including 4.000 patients. They will be divided into two groups: patients receiving standard outpatient observation (n=2000 and those enrolled for the program "Confidence" (n=2000. The total duration is 24 months. The trial will take place in two stages. In the first stage (0-12 months the impact of the program "Confidence" on therapy adherence and outcomes of cardiovascular diseases will be assessed. In the second stage (after the change of groups in 12 months, 12-24 months the effect of changing the way to remind patients of therapy adherence will be evaluated.Conclusion. The trial was designed in such a way as to show that the proposed program "Confidence" increases the proportion of patients who adhere to therapy in the cohort of those with coronary heart disease for two years after successful revascularization by using thrombolytic or stenting of the coronary arteries against the background of myocardial infarction.Received 13 February 2017. Accepted 9 March 2017.Financing: KRKA company’s grant. Sponsorship had no effect on data acquisition, analysis and interpretation.Conflict of interest: Kretov E.I. served as executive editor of “Endovascular surgery” section. All other authors declare no conflict of interest.Author contributionsStudy conception and design: Kretov E.I., Grazhdankin I.O., Baystrukov V.I., Zubarev D.D. Statistical data processing: Krestyaninov O.V., Kozyr K.V., Obedinskiy A.A., Prokhorikhin A.A.Drafting the article: Tarkova A.R., Anisimova V.D.Critical revision: Tarkova A.R., Anisimova V.D., Kretov E.I.

  13. Influence of cardiac stress protocol on myocardial perfusion imaging accuracy: The role of exercise level on the evaluation of ischemic burden.

    Science.gov (United States)

    Gimelli, Alessia; Liga, Riccardo; Pasanisi, Emilio Maria; Casagranda, Mirta; Coceani, Michele; Marzullo, Paolo

    2016-10-01

    Some specifics of cardiac stress protocols, i.e., stressor used or exercise level achieved, may impact myocardial perfusion imaging (MPI) accuracy. Four-hundred and seventy-five patients were submitted to MPI and coronary angiography. MPI was performed after exercise (303 patients) or dipyridamole stress (172 patients). A coronary stenosis ≥70% was considered significant. In case of exercise test, a peak heart rate (HR) 75% and stress protocol adopted (AUC .76 for exercise vs .78 for vasodilator; P = NS). However, in case of an exercise stress test, a significant interaction between peak %HR and MPI diagnostic power was evident. While an elevated accuracy was still maintained in "Group 1" patients (AUC .79; P vs maximal exercise = NS), a significant drop was demonstrated in "Group 2" patients (AUC .66; P vs maximal exercise = .012, and P vs "Group 1" = .042). The accuracy of MPI is not influenced by the stress protocol adopted. Exercise MPI maintains an elevated accuracy as long as the %HR remains >75%.

  14. Gated-SPECT myocardial perfusion imaging and coronary calcium score for evaluation of patients with acute chest pain and a normal or nondiagnostic electrocardiogram.

    Science.gov (United States)

    Peix, Amalia; Batista, Elida; Cabrera, Lázaro O; Rodríguez, Lydia; Padrón, Kenia; Saínz, Benito; Mendoza, Vladimir; Carrillo, Regla; Fernández, Yoel; Mena, Erick; Dondi, Maurizio

    2012-11-01

    To assess the ability of rest myocardial perfusion imaging (MPI) to rule out an acute coronary syndrome (ACS) in emergency department patients, as well as to investigate whether there exists a concordance between MPI and coronary calcium. Fifty-five patients with chest pain and a normal or nondiagnostic ECG were included. Clinical follow-up was carried out within 1 year. Sixteen patients (29%) showed an abnormal rest MPI, and in 11 (20%) the MPI was equivocal. There was a weak concordance between MPI and coronary arteries calcium score (CACS) (κ: 0.25). Coronary angiogram driven by a positive MPI was performed in 12 patients (23%), resulting in percutaneous coronary intervention in nine cases (75%). A positive MPI (abnormal or equivocal results) was associated with the occurrence of events in the follow-up (χ(2)=19.961, Ppatient presenting to the emergency department with acute chest pain and a normal or nondiagnostic ECG, with a positive MPI, the relative risk of having events during the first year was 7.5 (95% confidence interval: 2.8-19.2), Ppatients were free of events. Patients presenting with acute chest pain and a low-to-intermediate likelihood of coronary artery disease with a normal rest MPI have a very low probability of cardiac events during the first year. Coronary calcium score was not helpful in risk-stratifying these patients. © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins.

  15. Accelerating impact of diabetes mellitus on mortality in the years following an acute myocardial infarction. TRACE Study Group. Trandolapril Cardiac Evaluation

    DEFF Research Database (Denmark)

    Melchior, T; Køber, Lars Valeur; Madsen, C R

    1999-01-01

    AIMS: The development of risk associated with diabetes mellitus during long-term follow-up after a myocardial infarction has not been studied in detail. We have studied time-related changes of risk of death during 10 years of follow-up in a cohort of patients not treated with thrombolytic therapy...... between day 0 and day 30 was 1.17 and increased to 2.51 (P=0.0002) 7-9 years after discharge from hospital. A similar increase in the risk ratio of diabetes mellitus on mortality was observed in the TRACE cohort (risk ratio for days 0-30 was 1.03, and for years 4-6 was 1.74 (P=0.0001). CONCLUSION...... and follow-up was for 6 years. Outcome measure was total death. RESULTS: A diagnosis of diabetes mellitus was present in 12% of the two study populations. In multivariate analysis, diabetes mellitus had an independent adverse effect on mortality which increased with time. In the Glostrup cohort risk ratio...

  16. Low-dose adenosine stress echocardiography: Detection of myocardial viability

    Directory of Open Access Journals (Sweden)

    Nedeljkovic Milan

    2003-06-01

    Full Text Available Abstract Objective The aim of this study was to evaluate the diagnostic potential of low-dose adenosine stress echocardiography in detection of myocardial viability. Background Vasodilation through low dose dipyridamole infusion may recruit contractile reserve by increasing coronary flow or by increasing levels of endogenous adenosine. Methods Forty-three patients with resting dyssynergy, due to previous myocardial infarction, underwent low-dose adenosine (80, 100, 110 mcg/kg/min in 3 minutes intervals echocardiography test. Gold standard for myocardial viability was improvement in systolic thickening of dyssinergic segments of ≥ 1 grade at follow-up. Coronary angiography was done in 41 pts. Twenty-seven patients were revascularized and 16 were medically treated. Echocardiographic follow up data (12 ± 2 months were available in 24 revascularized patients. Results Wall motion score index improved from rest 1.55 ± 0.30 to 1.33 ± 0.26 at low-dose adenosine (p Conclusion Low-dose adenosine stress echocardiography test has high diagnostic potential for detection of myocardial viability in the group of patients with left ventricle dysfunction due to previous myocardial infarction. Low dose adenosine stress echocardiography may be adequate alternative to low-dose dobutamine test for evaluation of myocardial viability.

  17. CMB Temperature and Polarization Anisotropy Fundamentals

    OpenAIRE

    Hu, Wayne

    2002-01-01

    The tremendous experimental progress in cosmic microwave background (CMB) temperature and polarization anisotropy studies over the last few years has helped establish a standard paradigm for cosmology at intermediate epochs and has simultaneously raised questions regarding the physical processes at the two opposite ends of time. What is the physics behind the source of structure in the universe and the dark energy that is currently accelerating its expansion? We review the acoustic phenomenol...

  18. The Role of Post-Perovskite in Explaining Observations of Seismic Anisotropy

    Science.gov (United States)

    Cottaar, S.; Li, M.; McNamara, A. K.; Romanowicz, B. A.; Wenk, H. R.

    2014-12-01

    Increasing evidence is emerging for the presence of strong seismic anisotropy in D'' based on the observation of various seismic phases. To explain these observations in terms of crystal preferred orientation, and test for the presence and deformation mechanisms of post-perovskite, we apply a multi-disciplinary forward model approach. Our setup in this study is quite similar to our earlier study in 2D (Wenk et al., 2011). We employ a 3D geodynamical model with temperature-dependent viscosity and kinematic velocity boundary conditions defined at the surface of the Earth to form a broad downwelling slab. Tracers in the geodynamical model track the velocity gradient tensor in the slab at the surface down to the core-mantle boundary. The deformational information in the lower mantle is fed into a viscoplastic polycrystal plascticity model, in which we assume all deformation is accommodated by dislocation creep. We test models of either perovskite or post-perovskite mixed with periclase. For the post-perovskite phase we vary which slip system is most active. We average single crystal elastic constants over the crystal pole orientations to obtain seismically distinguishable models of anisotropy. The four resulting synthetic anisotropy models are evaluated against published seismic observations by comparing different anisotropic components: the radial anisotropy, the splitting for (sub-)vertical phases (i.e. azimuthal anisotropy), and the splitting for sub-horizontal phases. The patterns in shear radial anisotropy and splitting in sub-horizontal phases are consistent with post-perovskite with dominant slip on the (010)- and (001)-planes, confirming our earlier results in 2D. Overall, the (001)-model shows stronger anisotropy than the (010)-model, and its strongest patch localizes where the slab impinges on the core-mantle boundary. Radial anisotropy for P-waves could further constrain whether a slip system on the (010)-plane or the (001)-plane is most active. The

  19. Measurement of the thermopower anisotropy in iron arsenide

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, T., E-mail: fujii@crc.u-tokyo.ac.jp [Cryogenic Research Center, the University of Tokyo, 2-11-16 Yayoi, Bunkyo, Tokyo 113-0032 (Japan); Shirachi, T. [Department of Applied Physics, the University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Asamitsu, A. [Cryogenic Research Center, the University of Tokyo, 2-11-16 Yayoi, Bunkyo, Tokyo 113-0032 (Japan); Department of Applied Physics, the University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Ashikaga Institute of Technology, 268-1 Omae, Ashikaga, Tochigi 326-8558 (Japan)

    2016-11-15

    Highlights: • In this study, in order to investigate the origin of the in-plane anisotropy, the in-plane anisotropy of the thermopower was measured for the detwined single crystals of BFe{sub 2}As{sub 2}. And, we found no anisotropy in the thermopower above T{sub AFO}, although there is a large anisotropy in the resistivity. This result gives evidence that the anisotropy in the resistivity arise from the anisotropy of the scattering time, and the energy dependence of the scattering time can be considered negligible. In the case of iron pnictides, the proposed orbital ordering more likely results in an anisotropy of electronic structure below T{sub AFO}, whereas the spin-nematic ordering leads to an anisotropy of electron scattering above T{sub AFO}. Therefore, our results suggest that nematicity above T{sub AFO} results from anisotropic magnetic scattering. - Abstract: We investigated the in-plane anisotropy of the thermopower and electrical resistivity on detwinned single crystals of BaFe{sub 2}As{sub 2}. The in-plane anisotropy of the resistivity was clearly observed far above the magnetostructural transition temperature T{sub AFO}. While, the thermopower showed the in-plane anisotropy only below T{sub AFO}. These results are associated with the different origin of the anisotropy above and below T{sub AFO}. Since the thermopower does not depend on the scattering time, the anisotropy of the resistivity above T{sub AFO} is considered to be due to the anisotropic scattering. On the other hand, the anisotropy in the thermopower below T{sub AFO} is ascribed to the reconstructed Fermi surface.

  20. Global longitudinal strain predicts incident atrial fibrillation and stroke occurrence after acute myocardial infarction

    DEFF Research Database (Denmark)

    Olsen, Flemming Javier; Pedersen, Sune; Jensen, Jan Skov

    2016-01-01

    Patients with acute myocardial infarction are at increased risk of developing atrial fibrillation. We aimed to evaluate whether speckle tracking echocardiography improves risk stratification for atrial fibrillation in these patients.The study comprised of 373 patients with ST-segment elevation...... myocardial infarction (STEMI) treated with primary percutaneous coronary intervention. Patients had an echocardiogram performed at a median of 2 days after their STEMI. The echocardiograms consisted of conventional measurements and myocardial strain analysis by speckle tracking from 3 apical projections...

  1. Myocardial perfusion modeling using MRI

    DEFF Research Database (Denmark)

    Larsson, H B; Fritz-Hansen, T; Rostrup, Egill

    1996-01-01

    In the present study, it is shown that it is possible to quantify myocardial perfusion using magnetic resonance imaging in combination with gadolinium diethylenetriaminopentaacetic acid (Gd-DTPA). Previously, a simple model and method for measuring myocardial perfusion using an inversion recovery...

  2. Diurnal variations in myocardial metabolism

    Science.gov (United States)

    The heart is challenged by a plethora of extracellular stimuli over the course of a normal day, each of which distinctly influences myocardial contractile function. It is therefore not surprising that myocardial metabolism also oscillates in a time-of-day dependent manner. What is becoming increasin...

  3. Magnetic anisotropy and anisotropic damping in LSMO/STO(001)

    Science.gov (United States)

    Lee, Hankyu; Barsukov, Igor; Yang, Liu; Swartz, Adrian; Kim, Bongju; Hwang, Harold; Krivorotov, Ilya

    2015-03-01

    La0.7Sr0.3MnO3 (LSMO) is a promising material for spintronics applications due to its half-metallic nature. To successively exploit LSMO, both the magnetic anisotropy (MA) and damping need to be well understood and, ultimately, controlled. Here, we study 30 nm epitaxial LSMO thin films grown by pulsed laser deposition on TiO2 terminated (001)SrTiO3. By means of angle- and frequency dependent ferromagnetic resonance (FMR) at room temperature, we separate various contributions to the in-plane MA: i) The four-fold magnetocrystalline anisotropy is present but negligibly small. ii) The strongest contribution Buni = 4.2 mT is uniaxial with EA along [010]. While uniaxial MA in LSMO systems is commonly related to terrace formation from the substrate miscut, we find that the terrace direction and the MA symmetry axes do not correlate, indicating a different origin of the MA. By evaluating the FMR linewidth, three nonlinear magnetic damping channels due to the two-magnon scattering are found: j) The dominant four-fold contribution with maxima along axes emerges due to the crystalline defects. jj) A two-fold contribution with the maximum along [010] and jjj) a small two-fold contribution with maximum perpendicular to the terraces are identified.

  4. Polar Plate Theory for Orthogonal Anisotropy

    Science.gov (United States)

    Bailey, Michelle D.; Bower, Mark V.

    2000-01-01

    Laminated fiber-reinforced (or filamentary) composites are used today for their high strength-to-weight and stiffness-to-weight ratios. However, because of the anisotropic behavior of composites, determining the response on a macroscopic scale is challenging. This is particularly evident in the evaluation of the governing differential equations of a circular disk with the fibers of the lamina oriented with rectilinear orthogonality. This includes any situation involving a composite plate of circular geometry in which out-of-plane displacements due to load are desired, such as fastener pull through loading of a composite plate. Current analysis techniques use numerical methods with rectilinear coordinate systems to solve problems with circular geometry. These analyses over predict plate stiffness by 20% and underpredict failure by 70%. Consequently, there is a need to transform classical composite plate theory to a polar coordinate system. In order to better analyze structures with circular geometries the classical composite plate equations are transformed into the plate equations for a rectilinearly anisotropic composite in polar coordinates. A composite plate is typically a laminate of fibers in rectilinear directions. Subsequent to the lay-tip the necessary geometry is cut out of a rectangular plate. In a similar manner, the derivation of the plate equation starts with the fundamental definitions of strain, displacement and curvature and incorporates the material property angular dependence into the equilibrium equations for a differential polar element. In the transformed state, the stiffness coefficients are no longer constant, adding to the complexity of the governing differential equations. This paper discusses the new derivation and evaluation of the plate equations for a circular composite disk with orthogonal rectilinear anisotropy. The resultant new three partial differential equations, which describe the circular anisotropic plate, can be used to

  5. Sex differences in the effectiveness of early coronary computed tomographic angiography compared with standard emergency department evaluation for acute chest pain: the rule-out myocardial infarction with Computer-Assisted Tomography (ROMICAT)-II Trial.

    Science.gov (United States)

    Truong, Quynh A; Hayden, Douglas; Woodard, Pamela K; Kirby, Ruth; Chou, Eric T; Nagurney, John T; Wiviott, Stephen D; Fleg, Jerome L; Schoenfeld, David A; Udelson, James E; Hoffmann, Udo

    2013-06-25

    We evaluate sex-based differences in the effectiveness of early cardiac computed tomographic angiography (CCTA) and standard emergency department (ED) evaluation in patients with acute chest pain. In the Rule-Out Myocardial Infarction With Computer-Assisted Tomography (ROMICAT)-II multicenter, controlled trial, we randomized 1000 patients (47% women) 40 to 74 years of age with symptoms suggestive of acute coronary syndrome to an early CCTA or standard ED evaluation. In this prespecified analysis, women in the CCTA arm had a greater reduction in length of stay, lower hospital admission rates, and lesser increased cumulative radiation dose than men in a comparison of ED strategies (P for interaction ≤0.02). Although women had lower acute coronary syndrome rates than men (3% versus 12%; Pacute coronary syndrome rate (P for interaction acute coronary syndrome for either sex. No difference was observed in major adverse cardiac events between sexes and ED strategies (P for interaction =0.39). Women had more normal CCTA examinations than men (58% versus 37%; Pacute coronary syndrome. The findings may be explained by lower CAD prevalence and severity in women than men. http://www.clinicaltrials.gov. Unique identifier: NCT01084239.

  6. Low-dose dobutamine myocardial perfusion scintigraphy in the identification of viable myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, Renata Freire de [Instituto Hermes Pardini, Belo Horizonte, MG (Brazil). Dept. of Molecular Imaging and Diagnosis. Div. of Nuclear Medicine; Meneghetti, Jose Claudio [Instituto do Coracao (InCor-HC/FM/USP), Sao Paulo, SP (Brazil). Unit of Nuclear Medicine and Molecular Imaging; Barroso, Adelanir Antonio, E-mail: renatafreire@yahoo.com.b [Nuclear Medcenter, Belo Horizonte, MG (Brazil)

    2010-09-15

    Objective: to evaluate the increase in specificity of dual isotope myocardial perfusion gated SPECT ({sup 99m}Tcsestamibi/thallium-201), a highly sensitive method to detect viable myocardium, with addition of data on contractile reserve simultaneously acquired by low-dose dobutamine gated SPECT, similarly to echocardiography. Materials and methods: a total of 260 myocardial segments were assessed in 13 patients with myocardial infarction referred for investigation of myocardial viability before undergoing revascularization. Cellular integrity and contractile reserve were evaluated by dual isotope perfusion myocardial gated SPECT with thallium rest and redistribution images and post-stress {sup 99m}Tc-sestamibi gated-SPECT images under basal conditions and with low-dose dobutamine. The improvement in the contractile performance detected by post-revascularization {sup 99m}Tc-sestamibi gated SPECT was the parameter considered for determining myocardial viability. For the purpose of results analysis, the functional parameters of the myocardial segments were quantified at the different phases of the study and stratified according to their viability for a later post-revascularization functional comparison. Results: in the statistical analysis, systolic wall thickening demonstrated to be a relevant parameter in the evaluation of myocardial contractile reserve by this method, with a tendency of improvement in the specificity (84%), demonstrating higher values than those observed in the literature. Conclusion: this method tends to present an effective contribution in the assessment of myocardial viability. (author)

  7. Blood PGC-1α Concentration Predicts Myocardial Salvage and Ventricular Remodeling After ST-segment Elevation Acute Myocardial Infarction.

    Science.gov (United States)

    Fabregat-Andrés, Óscar; Ridocci-Soriano, Francisco; Estornell-Erill, Jordi; Corbí-Pascual, Miguel; Valle-Muñoz, Alfonso; Berenguer-Jofresa, Alberto; Barrabés, José A; Mata, Manuel; Monsalve, María

    2015-05-01

    Peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) is a metabolic regulator induced during ischemia that prevents cardiac remodeling in animal models. The activity of PGC-1α can be estimated in patients with ST-segment elevation acute myocardial infarction. The aim of the present study was to evaluate the value of blood PGC-1α levels in predicting the extent of necrosis and ventricular remodeling after infarction. In this prospective study of 31 patients with a first myocardial infarction in an anterior location and successful reperfusion, PGC-1α expression in peripheral blood on admission and at 72 hours was correlated with myocardial injury, ventricular volume, and systolic function at 6 months. Edema and myocardial necrosis were estimated using cardiac magnetic resonance imaging during the first week. At 6 months, infarct size and ventricular remodeling, defined as an increase > 10% of the left ventricular end-diastolic volume, was evaluated by follow-up magnetic resonance imaging. Myocardial salvage was defined as the difference between the edema and necrosis areas. Greater myocardial salvage was seen in patients with detectable PGC-1α levels at admission (mean [standard deviation (SD)], 18.3% [5.3%] vs 4.5% [3.9%]; P = .04). Induction of PGC-1α at 72 hours correlated with greater ventricular remodeling (change in left ventricular end-diastolic volume at 6 months, 29.7% [11.2%] vs 1.2% [5.8%]; P = .04). Baseline PGC-1α expression and an attenuated systemic response after acute myocardial infarction are associated with greater myocardial salvage and predict less ventricular remodeling. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

  8. [Energy metabolism and myocardial function in myocardiodystrophy].

    Science.gov (United States)

    Temirova, K V; Kurlygina, L A; Zavodskaia, I S; Novikova, N A

    1976-09-01

    A total of 92 patients with chronic tonsilitis and cardiovascular changes were subjected to clinical observations, ECG analysis, potassium and nitroglycerine tests, and studies of the lactic acid level and creatinekinase activity as indces of myocardial metabolism. The examinations were conducted prior to and following tonsillectomy. In a majority of patients a correlation was revealed between the degree of ECG changes and the serum lactic acid level, as well as between the ECG improvement and a reduction of the lactic acid level following tonsillectomy. Three stages of tonsillogenic myocardiodystrophy were distinguished. The obtained data indicate the rationale of the used tests for the evaluation of the myocardial meabolism alterations and of the efficacy of treatment of chronic tonsillitis patients.

  9. Integration of infarct size, tissue perfusion, and metabolism by hybrid cardiac positron emission tomography/computed tomography: evaluation in a porcine model of myocardial infarction.

    Science.gov (United States)

    Lautamäki, Riikka; Schuleri, Karl H; Sasano, Tetsuo; Javadi, Mehrbod S; Youssef, Amr; Merrill, Jennifer; Nekolla, Stephan G; Abraham, M Roselle; Lardo, Albert C; Bengel, Frank M

    2009-07-01

    Hybrid positron emission tomography/computed tomography (PET-CT) allows for combination of PET perfusion/metabolism imaging with infarct detection by CT delayed contrast enhancement. We used this technique to obtain biomorphological insights into the interrelation between tissue damage, inflammation, and microvascular obstruction early after myocardial infarction. A porcine model of left anterior descending coronary artery occlusion/reperfusion was studied. Seven animals underwent PET-CT within 3 days of infarction, and a control group of 3 animals was scanned at >4 weeks. Perfusion and glucose uptake were assessed by [(13)N]-ammonia/[(18)F]-deoxyglucose (FDG), and 64-slice CT delayed contrast enhancement was measured. In the acute infarct model, CT revealed a no-reflow phenomenon suggesting microvascular obstruction in 80% of all infarct segments. PET showed increased FDG uptake in 68% of the CT-defined infarct segments. Ex vivo staining and histology showed active inflammation in the acute infarct area as an explanation for increased glucose uptake. In chronic infarction, CT showed no microvascular obstruction and agreed well with matched perfusion/metabolism defects on PET. Perfusion/metabolism PET and delayed enhancement CT can be combined within a single hybrid PET-CT session. Increased regional FDG uptake in the acute infarct area is frequently observed. In contrast to the chronic infarct setting, this indicates tissue inflammation that is commonly associated with microvascular obstruction as identified by no reflow on CT. The consequences of these pathophysiological findings for subsequent ventricular remodeling should be explored in further studies.

  10. Improved quantification of collagen anisotropy with polarization-resolved second harmonic generation microscopy.

    Science.gov (United States)

    Hristu, Radu; Stanciu, Stefan G; Tranca, Denis E; Stanciu, George A

    2017-09-01

    Imaging tissue samples by polarization-resolved second harmonic generation microscopy provides both qualitative and quantitative insights into collagen organization in a label-free manner. Polarization-resolved second harmonic generation microscopy goes beyond simple intensity-based imaging by adding the laser beam polarization component and applying different quantitative metrics such as the anisotropy factor. It thus provides valuable information on collagen arrangement not available with intensity measurements alone. Current established approaches are limited to calculating the anisotropy factor for only a particular laser beam polarization and no general guidelines on how to select the best laser beam polarization have yet been defined. Here, we introduce a novel methodology for selecting the optimal laser beam polarization for characterizing tissues using the anisotropy in the purpose of identifying cancer signatures. We show that the anisotropy factor exhibits a similar laser beam polarization dependence to the second harmonic intensity and we combine it with the collagen orientation index computed by Fast Fourier Transform analysis of the recorded images to establish a framework for choosing the laser beam polarization that is optimal for an accurate interpretation of polarization-resolved second harmonic generation microscopy images and anisotropy maps, and hence a better differentiation between healthy and dysplastic areas. SHG image of skin tissue (a) and a selected area of interest for which we compute the SHG intensity (b) and anisotropy factor (c) dependence on the laser beam polarization and also the FFT spectrum (d) to evaluate the collagen orientation index. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Myocardial T1 mapping: application to patients with acute and chronic myocardial infarction.

    Science.gov (United States)

    Messroghli, Daniel R; Walters, Kevin; Plein, Sven; Sparrow, Patrick; Friedrich, Matthias G; Ridgway, John P; Sivananthan, Mohan U

    2007-07-01

    T(1) maps obtained with modified Look-Locker inversion recovery (MOLLI) can be used to measure myocardial T(1). We aimed to evaluate the potential of MOLLI T(1) mapping for the assessment of acute and chronic myocardial infarction (MI). A total of 24 patients with a first MI underwent MRI within 8 days and after 6 months. T(1) mapping was performed at baseline and at selected intervals between 2-20 min following administration of gadopentetate dimeglumine (Gd-DTPA). Delayed-enhancement (DE) imaging served as the reference standard for delineation of the infarct zone. On T(1) maps the myocardial T(1) relaxation time was assessed in hyperenhanced areas, hypoenhanced infarct cores, and remote myocardium. The planimetric size of myocardial areas with standardized T(1) threshold values was measured. Acute and chronic MI exhibited different T(1) changes. Precontrast threshold T(1) maps detected segmental abnormalities caused by acute MI with 96% sensitivity and 91% specificity. Agreement between measurements of infarct size from T(1) mapping and DE imaging was higher in chronic than in acute infarcts. Precontrast T(1) maps enable the detection of acute MI. Acute and chronic MI show different patterns of T(1) changes. Standardized T(1) thresholds provide the potential to dichotomously identify areas of infarction. (c) 2007 Wiley-Liss, Inc.

  12. Low-temperature magnetic anisotropy in micas and chlorite

    DEFF Research Database (Denmark)

    Biedermann, Andrea R.; Bender Koch, Christian; Lorenz, Wolfram E A

    2014-01-01

    use the magnetic anisotropy to understand a rock fabric, it is necessary to identify the minerals responsible for the magnetic anisotropy. Techniques have been developed to separate contributions of the ferrimagnetic, antiferromagnetic, paramagnetic, and diamagnetic susceptibilities to the anisotropy...... of magnetic susceptibility. Because diamagnetic and paramagnetic susceptibility are both linearly dependent on field, separation of the anisotropic contributions requires understanding how the degree of anisotropy of the paramagnetic susceptibility changes as a function of temperature. Note that diamagnetic...... susceptibility is not dependent on temperature. The increase in paramagnetic anisotropy at low temperature is used to separate the paramagnetic and diamagnetic subfabrics, and can be expressed by the p 77 factor. In this study, we determined p 77, which is the change in the degree of anisotropy (δk) between room...

  13. Improve myocardial T1 measurement in rats with a new regression model: application to myocardial infarction and beyond.

    Science.gov (United States)

    Zhang, Haosen; Ye, Qing; Zheng, Jie; Schelbert, Erik B; Hitchens, T Kevin; Ho, Chien

    2014-09-01

    To improve myocardial and blood T1 measurements with a multi-variable T1 fitting model specifically modified for a segmented multi-shot FLASH sequence. The proposed method was first evaluated in a series of phantoms simulating realistic tissues, and then in healthy rats (n = 8) and rats with acute myocardial infarction (MI) induced by coronary artery ligation (n = 8). By taking into account the saturation effect caused by sampling α-train pulses, and the longitudinal magnetization recovery between readouts, our model provided more accurate T1 estimate than the conventional three-parameter fit in phantoms under realistic gating procedures (error of -0.42 ± 1.73% versus -3.40 ± 1.46%, respectively, when using the measured inversion efficiency, β). The baseline myocardial T1 values in healthy rats was 1636.3 ± 23.4 ms at 7 Tesla. One day postligation, the T1 values in the remote and proximal myocardial areas were 1637.5 ± 62.6 ms and 1740.3 ± 70.5 ms, respectively. In rats with acute MI, regional differences in myocardial T1 values were observed both before and after the administration of gadolinium. The proposed method has improved T1 estimate as validated in phantoms and could advance applications in rodents using quantitative myocardial T1 mapping. Copyright © 2013 Wiley Periodicals, Inc.

  14. Myocardial extracellular volume fraction measurement in chronic total coronary occlusion: Association with myocardial injury, angiographic collateral flow, and functional recovery.

    Science.gov (United States)

    Chen, Yin-Yin; Ren, Dao-Yuan; Zeng, Meng-Su; Yang, Shan; Yun, Hong; Fu, Cai-Xia; Ge, Jun-Bo; Jin, Hang; Qian, Ju-Ying; Zhang, Wei-Guo

    2016-10-01

    To investigate whether myocardial extracellular volume fraction (ECV) measurement by cardiac MR is indicative of myocardial injury, angiographic collateral flow, and functional recovery in patients with chronic total coronary occlusion (CTO). A total of 50 CTO patients undergoing 1.5 Tesla MR were prospectively enrolled, and 28 underwent a second MR 6 months after revascularization. T1-mapping based indices, including pre- and postcontrast T1 values and ECV, were obtained from infarcted and non-infarcted myocardium, myocardial segments, and coronary territory. The severity of myocardial injury was rated by transmurality extent of infarction (TEI) and regional wall motion abnormalities (RWMA) score. Angiographic collateral flow was evaluated using Rentrop classification. Improvement in segmental wall motion at 6 months was also assessed. ECV and postcontrast T1 value significantly outperformed precontrast T1 value for identifying myocardial infarction (area under the receiver operating characteristic curve [AUC]: 0.998 and 0.953 versus 0.824, all P < 0.02). Myocardial ECV was strongly correlated with TEI (P = 0.000), RWMA score (P = 0.000), and collateral classification (P = 0.007 for left anterior descending artery [LAD] territory, P = 0.001 for non-LAD territory). Furthermore, the likelihood of functional recovery was better predicted by ECV than by late gadolinium enhancement (LGE) (AUC: 0.76 versus 0.68, P < 0.02). Myocardial ECV may be a useful surrogate to assess myocardial injury and angiographic collateral flow in CTO, and ECV provides incremental value to LGE in assessing functional recovery after revascularization. J. MAGN. RESON. IMAGING 2016;44:972-982. © 2016 International Society for Magnetic Resonance in Medicine.

  15. [Evaluation of long-term therapy influence with angiotensin converting enzyme inhibitor lisinopril on morphofunctional parameters of the left ventricle, peripheral artery endothelium disfunction and painless myocardial ischemia in premenopausal women with hypertension].

    Science.gov (United States)

    Khabibulina, M M

    2010-01-01

    Aim of the study was to assess influence of long-term therapy with angiotensin converting enzyme inhibitor lisinopril on morphofunctional parameters of the left ventricle (LV) and painless myocardial ischemia in 109 premenopausal women with stage II hypertension depending on functional state of peripheral artery endothelium. The results show that lisinopril therapy in premenopausal women with hypertension can stop or even cause regression of LV myocardial hypertrophy and produce favorable effect on LV remodeling mostly in women with concentric type of hypertrophy and/or without endothelial dysfunction, and has positive effect on frequency of painless myocardial ischemia events.

  16. Assessing the mechanical anisotropy and hysteresis while cycling IOP of porcine eyes before and after CXL by noncontact optical coherence elastography

    Science.gov (United States)

    Singh, Manmohan; Li, Jiasong; Raghunathan, Raksha; Han, Zhaolong; Nair, Achuth; Liu, Chih-Hao; Aglyamov, Salavt R.; Twa, Michael D.; Larin, Kirill V.

    2017-02-01

    Diseases such as keratoconus can alter the orientation of collagen fibrils in the cornea. Moreover, therapeutic interventions such as UV-A/riboflavin corneal collagen crosslinking (CXL) can alter the collagen fibril arrangement. Therefore, the anisotropic characteristics of the cornea can provide vital information about tissue integrity. In this work, we utilize noncontact elastic wave imaging optical coherence elastography (EWI-OCE) to assess the elastic anisotropy and hysteresis of in situ porcine corneas as various intraocular pressures (IOP). In addition, we evaluated the effects of CXL on the mechanical anisotropy and hysteresis. OCE measurements were made at stepped meridional angles, and a sliding window algorithm spatially mapped the elasticity. A modified planar anisotropy coefficient was utilized to quantify the elastic anisotropy of the corneas. The results show that the stiffness and elastic anisotropy of the corneas were significantly affected by CXL and IOP (P0.05).

  17. Quantification of regional myocardial oxygenation by magnetic resonance imaging: validation with positron emission tomography.

    Science.gov (United States)

    McCommis, Kyle S; Goldstein, Thomas A; Abendschein, Dana R; Herrero, Pilar; Misselwitz, Bernd; Gropler, Robert J; Zheng, Jie

    2010-01-01

    A comprehensive evaluation of myocardial ischemia requires measures of both oxygen supply and demand. Positron emission tomography (PET) is currently the gold standard for such evaluations, but its use is limited because of its ionizing radiation, limited availability, and high cost. A cardiac MRI method was developed for assessing myocardial oxygenation. The purpose of this study was to evaluate and validate this technique compared with PET during pharmacological stress in a canine model of coronary artery stenosis. Twenty-one beagles and small mongrel dogs without coronary artery stenosis (controls) or with moderate to severe acute coronary artery stenosis underwent MRI and PET imaging at rest and during dipyridamole vasodilation or dobutamine stress to induce a wide range of changes in cardiac perfusion and oxygenation. MRI first-pass perfusion imaging was performed to quantify myocardial blood flow and volume. The MRI blood oxygen level-dependent technique was used to determine the myocardial oxygen extraction fraction during pharmacological hyperemia. Myocardial oxygen consumption was determined by the Fick law. In the same dogs, (15)O-water and (11)C-acetate were used to measure myocardial blood flow and myocardial oxygen consumption, respectively, by PET. Regional assessments were performed for both MR and PET. MRI data correlated nicely with PET values for myocardial blood flow (R(2)=0.79, P<0.001), myocardial oxygen consumption (R(2)=0.74, P<0.001), and oxygen extraction fraction (R(2)=0.66, P<0.01). Cardiac MRI methods may provide an alternative to radionuclide imaging in settings of myocardial ischemia. Our newly developed quantitative MRI oxygenation imaging technique may be a valuable noninvasive tool to directly evaluate myocardial energetics and efficiency.

  18. Myocardial perfusion modeling using MRI

    DEFF Research Database (Denmark)

    Larsson, H B; Fritz-Hansen, T; Rostrup, Egill

    1996-01-01

    In the present study, it is shown that it is possible to quantify myocardial perfusion using magnetic resonance imaging in combination with gadolinium diethylenetriaminopentaacetic acid (Gd-DTPA). Previously, a simple model and method for measuring myocardial perfusion using an inversion recovery...... in the anterior myocardial wall were (mean +/- SD) Ki = 54 +/- 10 ml/100 g/min, lambda = 30 +/- 3 ml/100 g, Vb = 9 +/- 2 ml/100 g, delta T = 3.2 +/- 1.1 s. These results are in good agreement with similar results obtained by other methods....

  19. Compartmental analysis approach to fluorescence anisotropy: Perylene in viscous solvents

    OpenAIRE

    Piston, DW; Bilash, T; Gratton, E

    1989-01-01

    The fluorescence and polarization anisotropy decays of perylene in viscous solvents are investigated at several temperatures between -20 and 35 °C by using the technique of multifrequency phase and modulation fluorometry. The anisotropy decay data are globally analyzed over all temperatures studied and fit directly to physical quantities by using a compartmental model. We present a generalized compartmental model that can be used to calculate anisotropy decay arising from any type of intercon...

  20. Magnetic logic using nanowires with perpendicular anisotropy.

    Science.gov (United States)

    Jaworowicz, J; Vernier, N; Ferré, J; Maziewski, A; Stanescu, D; Ravelosona, D; Jacqueline, A S; Chappert, C; Rodmacq, B; Diény, B

    2009-05-27

    In addition to a storage function through the magnetization of nanowires, domain wall propagation can be used to trigger magnetic logic functions. Here, we present a new way to realize a pure magnetic logic operation by using magnetic nanowires with perpendicular anisotropy. Emphasis is given on the generation of the logic function 'NOT' that is based on the dipolar interaction between two neighbouring magnetic wires, which favours the creation of a domain wall. This concept has been validated on several prototypes and the results fit well with the expectations.

  1. Depression following myocardial infarction

    DEFF Research Database (Denmark)

    Larsen, Karen Kjær

    2013-01-01

    Myocardial infarction (MI) is a severe life event that is accompanied by an increased risk of depression. Mounting evidence suggests that post-MI depression is associated with adverse outcomes, but the underlying mechanisms of this association remain unclear, and no previous studies have examined...... whether the mental burden of MI is so heavy that it increases the risk of suicide. Although post-MI depression is common and burdensome, the condition remains under-recognised and under-treated. The development of new strategies to improve the quality of care for people with post-MI depression requires...... thorough understanding of the mechanisms that influence the prognosis as well as knowledge of the present care provided. The purpose of this PhD thesis is accordingly subdivided into four specific aims: 1. To estimate the prevalence of depression in people with MI after three months, and to estimate...

  2. Unusual arrhythmogenic myocardial disease

    Directory of Open Access Journals (Sweden)

    Christer Backman

    2014-01-01

    Full Text Available A twenty-two-year-old lady, with a 2-year history of recurrent tachyarrhythmia, presented with an episode of arrhythmia preceded by sore throat followed by chills, cough and exertional breathlessness, while abroad. She was commenced on penicillin V for 10 days with no improvement and because of worsening cough with purulent sputum she was prescribed broad-spectrum antibiotics and her chills disappeared. Two months later she had a relapse when she felt extremely tired, when a casualty ECG showed right bundle branch block and anterior T-wave inversion. An echocardiogram showed normal size cardiac chambers but the left ventricular basal posterior wall was hypokinetic with a bright echodense 2x3 cm subendocardial segment suggestive of localized fibrosis (Figure 1. The same finding was confirmed with Gadolinium enhanced CMR scan (Figure 2 which suggested a prior myocardial injury. The ejection fraction was normal at the time of CMR.

  3. Assessment of the performance of Core Strangle Test (CST) in determination of strength anisotropy in travertines (Sicak Cermik, Sivas, Turkey)

    Science.gov (United States)

    Yilmaz, Isik; Yucel, Ozge

    2013-04-01

    Anisotropy is one of the most distinct features that must be considered in rock engineering whether it is applied in civil, mining, geo-environmental, or petroleum engineering. Many rocks have anisotropic characteristics, i.e., their mechanical, thermal, seismic, and hydraulic properties vary with direction, and engineering applications that do not consider the anisotropic behaviour of rock produce errors of differing magnitudes, depending on the extent of rock anisotropy. Therefore, anisotropy has been a long-standing issue in rock engineering, beginning in the early developmental stages of rock mechanics. Anisotropic characteristics generally originate from the mineral foliation in metamorphic rocks, stratification in sedimentary rocks, and discontinuities in the rock mass. In this article, usefulness of Core Strangle Test (CST) in determination of strength anisotropy and its performance comparing with other indirect methods was evaluated. As a result of this study, higher performance was obtained, and CST led to considerably lower errors in determination of the strength anisotropy when compared with the results obtained from point load index and Brazilian tests. Moreover, it was found that CST can also be used as an alternative testing method for determination of strength anisotropy of rock core samples that a sufficient dimension can not be obtained and/or simple, fast and economical solutions may be needed. As one of the most important result of this study, the indirect methods where the tensile stresses considerably contribute to total stresses are unadvisable in determination of the strength anisotropy in which the anisotropy planes start to be parallel to the loading axis after approximately phi equal to 45 degrees.

  4. Preprocedural TIMI flow and mortality in patients with acute myocardial infarction treated by primary angioplasty

    NARCIS (Netherlands)

    De Luca, G.; Ernst, N.; Zijlstra, F.; van't Hof, A.W.J.; Hoorntje, J.C.A.; Dambrink, J.H.E.; Gosslink, A.T.M.; de Boer, M.J.; Suryapranata, H.

    2004-01-01

    Objectives The aim of the study was to evaluate the impact of preprocedural Thrombolysis In Myocardial Infarction (TIMI) flow on one-year mortality in patients with ST-segment elevation myocardial infarction (STEMI) treated by primary angioplasty. Background Although there is an excellent outcome

  5. Added value of attenuation-corrected myocardial perfusion scintigraphy in a patient with dextrocardia

    NARCIS (Netherlands)

    Slart, RHJA; De Boer, J; Jager, PL; Piers, DA

    2002-01-01

    A 52-year-old woman with dextrocardia was evaluated for chest pain. To exclude myocardial ischemia, she underwent a 2-day rest and bicycle stress myocardial perfusion study with 600 MBq (16 mCi) Tc-99m sestamibi. The rotational direction of the perpendicularly positioned camera heads was fixed and

  6. Assessment of myocardial enhancement during coronary CT angiography in critically ill patients

    Energy Technology Data Exchange (ETDEWEB)

    Mírka, Hynek, E-mail: mirka@fnplzen.cz [Department of Imaging Methods, Faculty of Medicine and University Teaching Hospital in Pilsen, Alej Svobody 80, 304 60 Plzeň (Czech Republic); Biomedical Centre, Faculty of Medicine in Plzen, Charles University in Prague, Alej Svobody 76, 304 60 Plzeň (Czech Republic); Ferda, Jiří, E-mail: ferda@fnplzen.cz [Department of Imaging Methods, Faculty of Medicine and University Teaching Hospital in Pilsen, Alej Svobody 80, 304 60 Plzeň (Czech Republic); Baxa, Jan, E-mail: baxaj@fnplzen.cz [Department of Imaging Methods, Faculty of Medicine and University Teaching Hospital in Pilsen, Alej Svobody 80, 304 60 Plzeň (Czech Republic)

    2016-10-15

    Highlights: • There are still unmet needs for the imaging, such as conditions with unknown cause that are not associated with dominant symptoms indicating primarily cardiac cause. • The contribution of the myocardial enhancement evaluation improves to determining the diagnosis of acute myocardial injury and choosing appropriate treatment. • When incorporating the myocardial enhancement assessment into the imaging algorithm, emphasis is placed on a uniform evaluation approach. • The color coded images of the myocardial enhancement in emergency situations help identify the most serious pathologies and shorten the time to adequate therapy. - Abstract: There are still challenges and unmet needs for the imaging techniques, such as conditions of uncertain origin in patients with clinically serious, life-threatening conditions with unknown cause that are not associated with dominant chest pain, ECG changes or other symptoms indicating a possible primarily cardiac or coronary cause. The contribution of the myocardial enhancement evaluation of urgent cardiac CTA scans significantly improves to determining the diagnosis of acute myocardial injury and choosing appropriate treatment. When incorporating the myocardial enhancement assessment into the imaging algorithm of an emergency department, emphasis is placed on a uniform imaging procedure and a uniform evaluation approach. The color coded images of the myocardial enhancement in emergency situations helps identify the most serious pathologies and shorten the time to adequate targeted therapy in patients.

  7. The incidence of suspected myocardial infarction in Dutch general practice in the period 1978-1994.

    NARCIS (Netherlands)

    Pal-de Bruin, K.M. van der; Verkleij, H.; Jansen, J.; Bartelds, A.; Kromhout, D.

    1998-01-01

    Aim: To evaluate how the incidence of suspected myocardial infarction has developed from 1978 to 1994 and to study the incidence of confirmed acute myocardial infarction in Dutch general practices during the period 1991-1994. Methods: In three periods (1978, 1983-1985 and 1991-1994) the incidence of

  8. Influence of fabric anisotropy on seismic responses of foundations

    Directory of Open Access Journals (Sweden)

    Jin Qin

    2015-04-01

    Full Text Available Earthquakes, as one of the well-known natural disasters, are highly destructive and unpredictable. Foundation failure due to liquefaction induced by earthquakes can cause casualties as well as significant damage to the building itself. Fabric anisotropy of soil grains is considered to be an important factor in dynamic soil response based on previous researches and laboratory tests. However, the limited availability of real physical data makes it less persuasive. In this study, a shake table installed on a geotechnical centrifuge is used to provide the designed seismic motions, and therefore, to simulate the realistic earthquake motion to foundations. Important parameters in the responses such as acceleration, excess pore pressure and deformation are evaluated to investigate the influence. Implications for design are also discussed.

  9. Anisotropy and Feedthrough in Magneto-Rayleigh-Taylor Instabilities

    Science.gov (United States)

    Weis, Matthew; Rittersdorf, Ian; Lau, Yue Ying; Zhang, Peng; Gilgenbach, Ronald; Zier, Jacob

    2011-10-01

    The magneto-Rayleigh-Taylor instability (MRT) in a finite slab is studied analytically using the ideal MHD model. The slab may be accelerated by an arbitrary combination of magnetic pressure and fluid pressure, thus allowing an arbitrary degree of anisotropy intrinsic to the acceleration mechanism. The magnetic field in different regions may assume arbitrary magnitude and direction tangential to the interface. In general, MRT retains robust growth if it exists. However, feedthrough may be substantially reduced if there are magnetic fields on both sides of the slab, and if the MRT mode invokes bending of the magnetic field lines. The analytically tractable eigenmode solutions allow an evaluation of the temporal evolution of MRT from random initial surface roughness. Work supported by DoE award DE-SC0002590, NSF award PHY 0903340, and by DoE through Sandia National Lab awards 240985 and 76822 to U. of Michigan. JCZ was supported by an NPSC fellowship through Sandia.

  10. Visual directional anisotropy does not mirror the directional anisotropy apparent in postural sway

    NARCIS (Netherlands)

    Holten, Vivian; Donker, Stella F.; Stuit, Sjoerd M.; Verstraten, Frans A J; van der Smagt, Maarten J.

    2015-01-01

    Presenting a large optic flow pattern to observers is likely to cause postural sway. However, directional anisotropies have been reported, in that contracting optic flow induces more postural sway than expanding optic flow. Recently, we showed that the biomechanics of the lower leg cannot account

  11. Molecular anisotropy effects in carbon K-edge scattering: depolarized diffuse scattering and optical anisotropy

    Energy Technology Data Exchange (ETDEWEB)

    Stone, Kevin H.

    2014-07-14

    Some polymer properties, such as conductivity, are very sensitive to short- and intermediate-range orientational and positional ordering of anisotropic molecular functional groups, and yet means to characterize orientational order in disordered systems are very limited. We demonstrate that resonant scattering at the carbon K-edge is uniquely sensitive to short-range orientation correlations in polymers through depolarized scattering at high momentum transfers, using atactic polystyrene as a well-characterized test system. Depolarized scattering is found to coexist with unpolarized fluorescence, and to exhibit pronounced anisotropy. We also quantify the spatially averaged optical anisotropy from low-angle reflectivity measurements, finding anisotropy consistent with prior visible, x-ray absorption, and theoretical studies. The average anisotropy is much smaller than that in the depolarized scattering and the two have different character. Both measurements exhibit clear spectral signatures from the phenyl rings and the polyethylene-like backbone. Discussion focuses on analysis considerations and prospects for using this depolarized scattering for studies of disorder in soft condensed matter.

  12. Theoretical Compton profile anisotropies in molecules and solids. VI. Compton profile anisotropies and chemical binding

    Energy Technology Data Exchange (ETDEWEB)

    Matcha, R.L.; Pettitt, B.M.

    1979-03-15

    An interesting empirical relationship between zero point Compton profile anisotropies ..delta..J (0) and nuclear charges is noted. It is shown that, for alkali halide molecules AB, to a good approximation ..delta..J (0) =N ln(Z/sub b//Z/sub a/).

  13. Facilitation of primary coronary angioplasty by early start of a glycoprotein 2b/3a inhibitor : Results of the ongoing tirofiban in myocardial infarction evaluation (On-TIME) trial

    NARCIS (Netherlands)

    van't Hof, A.W.J.; Ernst, N.; de Boer, M. J.; de Winter, R.; Boersma, E.; Bunt, T.; Petronio, S.; Gosselink, A.T.M.; Jap, W.; Hollak, F.; Hoorntje, J.C.A.; Suryapranata, H.; Dambrink, J.H.E.; Zijlstra, F.

    2004-01-01

    Aim Although primary angioplasty is effective despite additional transportation delay, improved patency before PCI might be obtained by starting pharmacological pre-treatment before transportation. Methods and Results From June 2001 to November 2002, 507 patients with acute myocardial infarction,

  14. Biomarkers in acute myocardial infarction

    National Research Council Canada - National Science Library

    Chan, Daniel; Ng, Leong L

    2010-01-01

    .... Biomarkers have been used to assist with timely diagnosis, while an increasing number of novel markers have been identified to predict outcome following an acute myocardial infarction or acute coronary syndrome...

  15. Texture and anisotropy analysis of Qusaiba shales

    KAUST Repository

    Kanitpanyacharoen, Waruntorn

    2011-02-17

    Scanning and transmission electron microscopy, synchrotron X-ray diffraction, microtomography and ultrasonic velocity measurements were used to characterize microstructures and anisotropy of three deeply buried Qusaiba shales from the Rub\\'al-Khali basin, Saudi Arabia. Kaolinite, illite-smectite, illite-mica and chlorite show strong preferred orientation with (001) pole figure maxima perpendicular to the bedding plane ranging from 2.4-6.8 multiples of a random distribution (m.r.d.). Quartz, feldspars and pyrite crystals have a random orientation distribution. Elastic properties of the polyphase aggregate are calculated by averaging the single crystal elastic properties over the orientation distribution, assuming a nonporous material. The average calculated bulk P-wave velocities are 6.2 km/s (maximum) and 5.5 km/s (minimum), resulting in a P-wave anisotropy of 12%. The calculated velocities are compared with those determined from ultrasonic velocity measurements on a similar sample. In the ultrasonic experiment, which measures the effects of the shale matrix as well as the effects of porosity, velocities are smaller (P-wave maximum 5.3 km/s and minimum 4.1 km/s). The difference between calculated and measured velocities is attributed to the effects of anisotropic pore structure and to microfractures present in the sample, which have not been taken into account in the matrix averaging. © 2011 European Association of Geoscientists & Engineers.

  16. Scanning anisotropy parameters in complex media

    KAUST Repository

    Alkhalifah, Tariq Ali

    2011-03-21

    Parameter estimation in an inhomogeneous anisotropic medium offers many challenges; chief among them is the trade-off between inhomogeneity and anisotropy. It is especially hard to estimate the anisotropy anellipticity parameter η in complex media. Using perturbation theory and Taylor’s series, I have expanded the solutions of the anisotropic eikonal equation for transversely isotropic (TI) media with a vertical symmetry axis (VTI) in terms of the independent parameter η from a generally inhomogeneous elliptically anisotropic medium background. This new VTI traveltime solution is based on a set of precomputed perturbations extracted from solving linear partial differential equations. The traveltimes obtained from these equations serve as the coefficients of a Taylor-type expansion of the total traveltime in terms of η. Shanks transform is used to predict the transient behavior of the expansion and improve its accuracy using fewer terms. A homogeneous medium simplification of the expansion provides classical nonhyperbolic moveout descriptions of the traveltime that are more accurate than other recently derived approximations. In addition, this formulation provides a tool to scan for anisotropic parameters in a generally inhomogeneous medium background. A Marmousi test demonstrates the accuracy of this approximation. For a tilted axis of symmetry, the equations are still applicable with a slightly more complicated framework because the vertical velocity and δ are not readily available from the data.

  17. Results from the Wilkinson Microwave Anisotropy Probe

    Science.gov (United States)

    Komatsu, E.; Bennett, Charles L.; Komatsu, Eiichiro

    2015-01-01

    The Wilkinson Microwave Anisotropy Probe (WMAP) mapped the distribution of temperature and polarization over the entire sky in five microwave frequency bands. These full-sky maps were used to obtain measurements of temperature and polarization anisotropy of the cosmic microwave background with the unprecedented accuracy and precision. The analysis of two-point correlation functions of temperature and polarization data gives determinations of the fundamental cosmological parameters such as the age and composition of the universe, as well as the key parameters describing the physics of inflation, which is further constrained by three-point correlation functions. WMAP observations alone reduced the flat ? cold dark matter (Lambda Cold Dark Matter) cosmological model (six) parameter volume by a factor of > 68, 000 compared with pre-WMAP measurements. The WMAP observations (sometimes in combination with other astrophysical probes) convincingly show the existence of non-baryonic dark matter, the cosmic neutrino background, flatness of spatial geometry of the universe, a deviation from a scale-invariant spectrum of initial scalar fluctuations, and that the current universe is undergoing an accelerated expansion. The WMAP observations provide the strongest ever support for inflation; namely, the structures we see in the universe originate from quantum fluctuations generated during inflation.

  18. Anisotropy studies on cuboidal shear device

    Energy Technology Data Exchange (ETDEWEB)

    Sivakugan, N. (Sultan Qaboos Univ., Al-Khod (Oman)); Chameau, J.L. (Georgia Inst. of Tech., Atlanta (United States)); Holtz, R.D. (Univ. of Washington, Seattle (United States))

    1993-06-01

    Anisotropy of clays was studied from cuboidal shear tests on two different clays that were artificially sedimented in a slurry consolidometer. These were supplemented by consolidation tests on specimens cut at different orientations. For one-dimensionally consolidated specimens, a significant increase was observed in the angle of internal friction when the specimens were loaded horizontally. For isotropically consolidated specimens, the angle of internal friction was about the same for vertical and horizontal loading. From the limited data available, it appears that the difference increases with the inherent anisotropy of the clay fabric. It was also found that when the one-dimensionally consolidated clay specimen is loaded horizontally, the rotation of principal stresses takes place. This results in the development of very high pore pressures at failure. The substantial increase in the angle of internal friction and the development of very high pore pressures at failure for horizontal loading of one-dimensionally consolidated clays are very important considerations in the geotechnical problems in which the soil is loaded horizontally.

  19. Anisotropy in turbulence profiles of stratified wakes

    Science.gov (United States)

    Spedding, G. R.

    2001-08-01

    At sufficiently high values of the Reynolds number (Re⩾4.5×103) and internal Froude number (F⩾4), initially turbulent bluff body wakes evolve in the presence of a stable background density gradient with wake-averaged mean and turbulence length and velocity scales that are independent of Re and F for at least two orders of magnitude extension in both parameters. The way in which the initially three-dimensional motions transition to the characteristic (and Re- and F-independent) late wakes (where vertical velocities, w≪u,v) is both of great practical interest, and complex, hence somewhat unclear. Here, digital particle imaging velocimetry type measurements on towed-sphere wakes are described, so that the development of anisotropy can be measured by the time development of turbulence profiles in horizontal and vertical centerplanes. The observed anisotropies can be associated with energy transfer to internal wave modes, and suppression of other vertical displacements, that contrasts with sphere wakes at similar Re in a homogeneous fluid. Maximum Reynolds stresses occur at the boundary of a sinuous undulation of the wake, which increases in amplitude up to Nt≈60 (N is the buoyancy frequency that characterizes the strength of the stratification). Although an intrinsic wake profile instability cannot be excluded, the observed wake element spacings can be accounted for by known spiral and Kelvin-Helmholtz instabilities in the near wake.

  20. Magnetic anisotropy of isolated Cobalt nanoplatelets

    Science.gov (United States)

    Strandberg, Tor Olof; Canali, Carlo M.; MacDonald, Allan H.

    2005-03-01

    Motivated by experiments performed by M.H. Pan et al. [1], we have undertaken a theoretical study of the the magnetic properties of two-monolayer-thick Co nanoplatelets with an equilateral triangular shape. We are using a microscopic Slater-Koster tight-binding model with atomic exchange and spin-orbit interactions, that has been designed to realistically capture the salient magnetic features of large magnetic nanoclusters [2]. Two different truncations of the fcc lattice have been studied, in which the nanoplatelet surface is aligned parallel to the [111] and [001] planes respectively. We find that the higher coordination number in the [111] truncation is more likely to reproduce the perpendicular easy direction found in experiment. Qualitatively, the most important model parameter governing the anisotropy is found to be the intra-atomic exchange integral J. If we set the value of J so as to reproduce the experimentally observed magnitude of the magnetic moments, we find both quasi-easy-planes and perpendicular easy directions. Increasing J, we find that, in agreement with experiment, the easy-axis of magnetization is predominantly perpendicular to the surface, and the magnetic anisotropy energy is anomalously large. The possible role of hybridization with substrate surface states in the experimental systems will be discussed. [1] M.H. Pan et al, Nanoletters V5, no 1, 87-90 (2005) [2] A. Cehovin et al, Phys. Rev. B, 66, 094430 (2002)

  1. Rationale and design of a multicentre, prospective, randomised, controlled clinical trial to evaluate the efficacy of the adipose graft transposition procedure in patients with a myocardial scar: the AGTP II trial.

    Science.gov (United States)

    Gastelurrutia, Paloma; Gálvez-Montón, Carolina; Cámara, Maria Luisa; Bustamante-Munguira, Juan; García-Pavia, Pablo; Avanzas, Pablo; Alberto San Román, J; Pascual-Figal, Domingo; Teresa, Eduardo de; Crespo-Leiro, Maria G; Manito, Nicolás; Núñez, Julio; Fernández-Avilés, Francisco; Caballero, Ángel; Teis, Albert; Lupón, Josep; Brugada, Ramón; Martín, Carlos; Silva, Jacobo; Revilla-Orodea, Ana; Cánovas, Sergio J; Melero, Jose M; Cuenca-Castillo, Jose J; Gonzalez-Pinto, Angel; Bayes-Genis, Antoni

    2017-08-04

    Cardiac adipose tissue is a source of progenitor cells with regenerative capacity. Studies in rodents demonstrated that the intramyocardial delivery of cells derived from this tissue improves cardiac function after myocardial infarction (MI). We developed a new reparative approach for damaged myocardium that integrates the regenerative properties of cardiac adipose tissue with tissue engineering. In the adipose graft transposition procedure (AGTP), we dissect a vascularised flap of autologous pericardial adipose tissue and position it over the myocardial scarred area. Following encouraging results in acute and chronic MI porcine models, we performed the clinical trial (NCT01473433, AdiFLAP trial) to evaluate safety in patients with chronic MI undergoing coronary artery bypass graft. The good safety profile and trends in efficacy warranted a larger trial. The AGTP II trial (NCT02798276) is an investigator initiated, prospective, randomised, controlled, multicentre study to assess the efficacy of the AGTP in 108 patients with non-revascularisable MI. Patients will be assigned to standard clinical practice or the AGTP. The primary endpoint is change in necrotic mass ratio by gadolinium enhancement at 91 and 365 days. Secondary endpoints include improvement in regional contractibility by MRI at 91 and 365 days; changes in functional MRI parameters (left ventricular ejection fraction, left and right ventricular geometric remodelling) at 91 and 365 days; levels of N-terminal prohormone of brain natriuretic peptide (NT-proBNP) at 7, 91 and 365 days; appearance of arrhythmias from 24 hour Holter monitoring at 24 hours, and at 91 and 365 days; all cause death or re-hospitalisation at 365 days; and cardiovascular death or re-hospitalisation at 365 days. The institutional review board approved the trial which will comply with the Declaration of Helsinki. All patients will provide informed consent. It may offer a novel, effective and technically simple technique for patients

  2. Cardiac magnetic resonance myocardial perfusion reserve index is reduced in women with coronary microvascular dysfunction. A National Heart, Lung, and Blood Institute-sponsored study from the Women's Ischemia Syndrome Evaluation.

    Science.gov (United States)

    Thomson, Louise E J; Wei, Janet; Agarwal, Megha; Haft-Baradaran, Afsaneh; Shufelt, Chrisandra; Mehta, Puja K; Gill, Edward B; Johnson, B Delia; Kenkre, Tanya; Handberg, Eileen M; Li, Debiao; Sharif, Behzad; Berman, Daniel S; Petersen, John W; Pepine, Carl J; Bairey Merz, C Noel

    2015-04-01

    Women with signs and symptoms of ischemia and no obstructive coronary artery disease often have coronary microvascular dysfunction (CMD), diagnosed by invasive coronary reactivity testing (CRT). Although traditional noninvasive stress imaging is often normal in CMD, cardiac MRI may be able to detect CMD in this population. Vasodilator stress cardiac MRI was performed in 118 women with suspected CMD who had undergone CRT and 21 asymptomatic reference subjects. Semi-quantitative evaluation of the first-pass perfusion images was completed to determine myocardial perfusion reserve index (MPRI). The relationship between CRT findings and MPRI was examined by Pearson correlations, logistic regression, and sensitivity/specificity. Symptomatic women had lower mean pharmacological stress MPRI compared with reference subjects (1.71±0.43 versus 2.23±0.37; P<0.0001). Lower MPRI was predictive of ≥1 abnormal CRT variables (odds ratio =0.78 [0.70, 0.88], P<0.0001, c-statistic 0.78 [0.68, 0.88]). An MPRI threshold of 1.84 predicted CRT abnormality with sensitivity 73% and specificity 74%. Noninvasive cardiac MRI MPRI can detect CMD defined by invasive CRT. Further work is aimed to optimize the noninvasive identification and management of CMD patients. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00832702. © 2015 American Heart Association, Inc.

  3. Evaluation of occupational radiation dose in nuclear medicine: radiopharmaceutical administration to scintiscanning exams of myocardial perfusion; Avaliacao da dose de radiacao ocupacional em medicina nuclear: administracao de radiofarmacos em exames de cintilografria de perfusao miocardica

    Energy Technology Data Exchange (ETDEWEB)

    Komatsu, Cassio V., E-mail: cassiok@yahoo.com [Medicina Nuclear do Triangulo (MNT), Uberlandia, MG (Brazil); Michelin, Charlie A.; Jakubiak, Rosangela R., E-mail: charlie@utfpr.edu.br, E-mail: requi@utfpr.edu.br [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil); Lemes, Alyne O.; Silva, Juliana L.M., E-mail: alyne275@gmail.com, E-mail: jujumontesdocinho@gmail.com [Faculdade do Trabalho (FATRA), Uberlandia, MG (Brazil)

    2013-11-01

    In nuclear medicine, workers directly involved in exams are constantly exposed to ionizing radiation. The procedure for administration of the radiopharmaceutical to the patient is one of the most critical times of exposure. In tests of myocardial perfusion scintigraphy (MPS) administration of radiopharmaceutical repeats the steps of rest and cardiac stress. In this study, we used a Geiger -Mueller detector for measuring occupational radiation doses for during the administration of technetium- {sup 99m}- sestamibi in MPS tests. In the evaluation, discriminated the stages of examination and related professional experience time to doses measures at home. It were followed 110 procedures at home (55 conducted by professionals with over 5 years experience and 55 conducted by professionals with less than 1 year of experience) and 55 effort procedures. The results showed that the rest of the procedure time and dose are related to the experience of the worker. More experienced workers were faster (mean: 43 {+-} 16 vs 67 {+-} 25 seconds / procedure), and therefore received lower doses (mean 0.57 {+-} 0.16 versus 0.80 {+-} 0.24 {mu}Sv / procedure), both with statistical significance (p <0.001). In step effort, there were procedures lasting longer (mean: 19 {+-} 2 minutes / procedure), which resulted in higher doses (mean 3.0 {+-} 0.6 {mu}Sv / procedure)

  4. CMR of microvascular obstruction and hemorrhage in myocardial infarction

    Directory of Open Access Journals (Sweden)

    Wu Katherine C

    2012-09-01

    Full Text Available Abstract Microvascular obstruction (MO or no-reflow phenomenon is an established complication of coronary reperfusion therapy for acute myocardial infarction. It is increasingly recognized as a poor prognostic indicator and marker of subsequent adverse LV remodeling. Although MO can be assessed using various imaging modalities including electrocardiography, myocardial contrast echocardiography, nuclear scintigraphy, and coronary angiography, evaluation by cardiovascular magnetic resonance (CMR is particularly useful in enhancing its detection, diagnosis, and quantification, as well as following its subsequent effects on infarct evolution and healing. MO assessment has become a routine component of the CMR evaluation of acute myocardial infarction and will increasingly play a role in clinical trials of adjunctive reperfusion agents and strategies. This review will summarize the pathophysiology of MO, current CMR approaches to diagnosis, clinical implications, and future directions needed for improving our understanding of this common clinical problem.

  5. Safety, hemodynamic profile, and feasibility of dobutamine stress technetium myocardial perfusion single-photon emission CT imaging for evaluation of coronary artery disease in the elderly

    NARCIS (Netherlands)

    A. Elhendy (Abdou); J.J. Bax (Jeroen); R. Valkema (Roelf); A.E.M. Reijs (Ambroos); E.P. Krenning (Eric); J.R.T.C. Roelandt (Jos); R.T. van Domburg (Ron)

    2000-01-01

    textabstractOBJECTIVES: Cardiovascular disease is the leading cause of morbidity and mortality in the elderly. The evaluation of coronary artery disease by exercise stress testing is frequently limited by the patient's inability to exercise. Although pharmacologic

  6. Comparison of two- versus three-dimensional myocardial contrast echocardiography for assessing subendocardial perfusion abnormality after percutaneous coronary intervention in patients with acute myocardial infarction.

    Science.gov (United States)

    Iwakura, Katsuomi; Ito, Hiroshi; Okamura, Atsushi; Kurotobi, Toshiya; Koyama, Yasushi; Date, Motoo; Inoue, Koichi; Nagai, Hiroyuki; Imai, Michio; Arita, Yo; Toyoshima, Yuko; Ozawa, Makito; Fujii, Kenshi

    2007-11-15

    Myocardial contrast echocardiography (MCE) visualizes myocardial perfusion abnormalities after acute myocardial infarction. However, the limited view of 2-dimensional echocardiography reduces its ability to estimate perfusion abnormalities, especially in the subendocardial region. Three-dimensional echocardiography provides images of the left ventricular endocardium directly. This study was conducted to evaluate the ability of 3-dimensional MCE to assess abnormalities of subendocardial perfusion. Intracoronary 2- and 3-dimensional MCE was performed after primary percutaneous coronary intervention in 47 patients with acute myocardial infarction. Myocardial perfusion within the risk area was evaluated as good, poor, or no reflow on 2-dimensional MCE or as good, poor, or no myocardial opacification in endocardium on 3-dimensional MCE. The 2 methods showed different distributions of perfusion patterns: good, poor, and no reflow on 2-dimensional MCE in 31 (66%), 9 (19%), and 7 (15%) patients and good, poor, and no myocardial opacification in endocardium on 3-dimensional MCE in 17 (36%), 16 (34%), and 14 (20%) patients, respectively. Although only 19 patients (61%) with good reflow on 2-dimensional MCE showed myocardial perfusion grade 3 on angiography, 16 of 17 patients (94%) with good myocardial opacification in endocardium on 3-dimensional MCE showed myocardial perfusion grade 3. Although there were no significant differences in peak creatine kinase among the 3 subsets classified by 2-dimensional MCE, peak creatine kinase showed significant differences not only among the 3 groups but also among the subsets classified by 3-dimensional MCE. Classification by 3-dimensional MCE also predicted regional wall motion after 4.6 +/- 2.7 months, with significant differences between each pair of groups, whereas there was significant overlap of these values between the group with poor reflow and other 2 groups by 2-dimensional MCE. In conclusion, 3-dimensional MCE is a feasible

  7. Impacts of Streambed Heterogeneity and Anisotropy on Residence Time of Hyporheic Zone.

    Science.gov (United States)

    Liu, Suning; Chui, Ting Fong May

    2017-09-14

    The hyporheic zone (HZ), which is the region beneath or alongside a streambed, plays an important role in the stream's ecology. The duration that a water molecule or a solute remains within the HZ, or residence time (RT), is one of the most common metrics used to evaluate the function of the HZ. The RT is greatly influenced by the streambed's hydraulic conductivity (K), which is intrinsically difficult to characterize due to its heterogeneity and anisotropy. Many laboratory and numerical studies of the HZ have simplified the streambed K to a constant, thus producing RT values that may differ from those gathered from the field. Some studies have considered the heterogeneity of the HZ, but very few have accounted for anisotropy or the natural K distributions typically found in real streambeds. This study developed numerical models in MODFLOW to examine the influence of heterogeneity and anisotropy, and that of the natural K distribution in a streambed, on the RT of the HZ. Heterogeneity and anisotropy were both found to shorten the mean and median RTs while increasing the range of the RTs. Moreover, heterogeneous K fields arranged in a more orderly pattern had longer RTs than those with random K distributions. These results could facilitate the design of streambed K values and distributions to achieve the desired RT during river restoration. They could also assist the translation of results from the more commonly considered homogeneous and/or isotropic conditions into heterogeneous and anisotropic field situations. © 2017, National Ground Water Association.

  8. Effect of Evolutionary Anisotropy on Earing Prediction in Cylindrical Cup Drawing

    Science.gov (United States)

    Choi, H. J.; Lee, K. J.; Choi, Y.; Bae, G.; Ahn, D.-C.; Lee, M.-G.

    2017-05-01

    The formability of sheet metals is associated with their planar anisotropy, and finite element simulations have been applied to the sheet metal-forming process by describing the anisotropic behaviors using yield functions and hardening models. In this study, the evaluation of anisotropic constitutive models was performed based on the non-uniform height profile or earing in circular cylindrical cup drawing. Two yield functions, a quadratic Hill1948 and a non-quadratic Yld2000-2d model, were used under non-associated and associated flow rules, respectively, to simultaneously capture directional differences in yield stress and r value. The effect of the evolution of anisotropy on the earing prediction was also investigated by employing simplified equivalent plastic strain rate-dependent anisotropic coefficients. The computational results were in good agreement with experiments when the proper choice of the yield function and flow rule, which predicts the planar anisotropy, was made. Moreover, the accuracy of the earing profile could be significantly enhanced if the evolution of anisotropy between uniaxial and biaxial stress states was additionally considered.

  9. Prevalence and Correlates of Myocardial Scar in a US Cohort.

    Science.gov (United States)

    Turkbey, Evrim B; Nacif, Marcelo S; Guo, Mengye; McClelland, Robyn L; Teixeira, Patricia B R P; Bild, Diane E; Barr, R Graham; Shea, Steven; Post, Wendy; Burke, Gregory; Budoff, Matthew J; Folsom, Aaron R; Liu, Chia-Ying; Lima, João A; Bluemke, David A

    2015-11-10

    Myocardial scarring leads to cardiac dysfunction and poor prognosis. The prevalence of and factors associated with unrecognized myocardial infarction and scar have not been previously defined using contemporary methods in a multiethnic US population. To determine prevalence of and factors associated with myocardial scar in middle- and older-aged individuals in the United States. The Multi-Ethnic Study of Atherosclerosis (MESA) study is a population-based cohort in the United States. Participants were aged 45 through 84 years and free of clinical cardiovascular disease (CVD) at baseline in 2000-2002. In the 10th year examination (2010-2012), 1840 participants underwent cardiac magnetic resonance (CMR) imaging with gadolinium to detect myocardial scar. Cardiovascular disease risk factors and coronary artery calcium (CAC) scores were measured at baseline and year 10. Logistic regression models were used to estimate adjusted odds ratios (ORs) for myocardial scar. Cardiovascular risk factors, CAC scores, left ventricle size and function, and carotid intima-media thickness. Myocardial scar detected by CMR imaging. Of 1840 participants (mean [SD] age, 68 [9] years, 52% men), 146 (7.9%) had myocardial scars, of which 114 (78%) were undetected by electrocardiogram or by clinical adjudication. In adjusted models, age, male sex, body mass index, hypertension, and current smoking at baseline were associated with myocardial scar at year 10. The OR per 8.9-year increment was 1.61 (95% CI, 1.36-1.91; P scar at year 10. Compared with a CAC score of 0, the OR for scores from 1 through 99 was 2.4 (95% CI, 1.5-3.9); from 100 through 399, 3.0 (95% CI, 1.7-5.1), and 400 or higher, 3.3 (95% CI, 1.7-6.1) (P ≤ .001). The CAC score significantly added to the association of myocardial scar with age, sex, race/ethnicity, and traditional CVD risk factors (C statistic, 0.81 with CAC vs 0.79 without CAC, P = .01). The prevalence of myocardial scars in a US community-based multiethnic cohort

  10. Regional Mechanics Determine Collagen Fiber Structure in Healing Myocardial Infarcts

    Science.gov (United States)

    Fomovsky, Gregory M.; Rouillard, Andrew D.; Holmes, Jeffrey W.

    2012-01-01

    Following myocardial infarction, the mechanical properties of the healing infarct are an important determinant of heart function and the risk of progression to heart failure. In particular, mechanical anisotropy (having different mechanical properties in different directions) in the healing infarct can preserve pump function of the heart. Based on reports of different collagen structures and mechanical properties in various animal models, we hypothesized that differences in infarct size, shape, and/or location produce different patterns of mechanical stretch that guide evolving collagen fiber structure. We tested the effects of infarct shape and location using a combined experimental and computational approach. We studied mechanics and collagen fiber structure in cryoinfarcts in 53 Sprague-Dawley rats and found that regardless of shape or orientation, cryoinfarcts near the equator of the left ventricle stretched primarily in the circumferential direction and developed circumferentially aligned collagen, while infarcts at the apex stretched similarly in the circumferential and longitudinal direction and developed randomly oriented collagen. In a computational model of infarct healing, an effect of mechanical stretch on fibroblast and collagen alignment was required to reproduce the experimental results. We conclude that mechanical environment determines collagen fiber structure in healing myocardial infarcts. Our results suggest that emerging post-infarction therapies that alter regional mechanics will also alter infarct collagen structure, offering both potential risks and novel therapeutic opportunities. PMID:22418281

  11. Advanced Cardiac MR Imaging for Myocardial Characterization and Quantification: T1 Mapping.

    Science.gov (United States)

    Hwang, Sung Ho; Choi, Byoung Wook

    2013-01-01

    Magnetic resonance as an imaging modality provides an excellent soft tissue differentiation, which is an ideal choice for cardiac imaging. Cardiac magnetic resonance (CMR) allows myocardial tissue characterization, as well as comprehensive evaluation of the structures. Although late gadolinium enhancement after injection of the gadolinium extracellular contrast agent has further extended our ability to characterize the myocardial tissue, it also has limitations in the quantification of enhanced myocardial tissue pathology, and the detection of diffuse myocardial disease, which is not easily recognized by enhancement contrast. Recently, the remarkable advances in CMR technique, such as T1 mapping, which can quantitatively evaluate myocardial status, showed potentials to overcome limitations of existing CMR sequences and to expand the application of CMR. This article will review the technical and clinical points to be considered in the practical use of pre- and post-contrast T1 mapping.

  12. The role of cardiac magnetic resonance imaging following acute myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Wong, Dennis T.L.; Richardson, James D.; Puri, Rishi; Nelson, Adam J.; Teo, Karen S.L.; Worthley, Matthew I. [Royal Adelaide Hospital, Cardiovascular Research Centre, Adelaide (Australia); University of Adelaide, Department of Medicine, Adelaide (Australia); Bertaso, Angela G. [Royal Adelaide Hospital, Cardiovascular Research Centre, Adelaide (Australia); Worthley, Stephen G. [Royal Adelaide Hospital, Cardiovascular Research Centre, Adelaide (Australia); University of Adelaide, Department of Medicine, Adelaide (Australia); Cardiovascular Investigational Unit, Adelaide, SA (Australia)

    2012-08-15

    Advances in the management of myocardial infarction have resulted in substantial reductions in morbidity and mortality. However, after acute treatment a number of diagnostic and prognostic questions often remain to be answered, whereby cardiac imaging plays an essential role. For example, some patients will sustain early mechanical complications after infarction, while others may develop significant ventricular dysfunction. Furthermore, many individuals harbour a significant burden of residual coronary disease for which clarification of functional ischaemic status and/or viability of the suspected myocardial territory is required. Cardiac magnetic resonance (CMR) imaging is well positioned to fulfil these requirements given its unparalleled capability in evaluating cardiac function, stress ischaemia testing and myocardial tissue characterisation. This review will focus on the utility of CMR in resolving diagnostic uncertainty, evaluating early complications following myocardial infarction, assessing inducible ischaemia, myocardial viability, ventricular remodelling and the emerging role of CMR-derived measures as endpoints in clinical trials. (orig.)

  13. Detection of myocardial ischemia with myocardial perfusion SPECT in patients with diabetes mellitus

    Energy Technology Data Exchange (ETDEWEB)

    Seo, J. H.; Jeong, S. Y.; Bae, J. H.; Anh, B. C.; Lee, J.; Lee, K. B [Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2004-07-01

    Diabetes mellitus(DM) is a critical disease associated with higher rates of cardiovascular morbidity and mortality. Atherosclerosis accounts for 65-80% of all deaths in diabetic patients and patients with DM are known to show high prevalence of coronary artery diseases(CAD). We evaluated the incidence of scintigraphic evidence of CAD in diabetic patients and results were compared with cardiovascular symptoms and clinical factors. 169 patients with DM(mean age 629years, 68 males) were referred for evaluation of CAD between Jan 2002 and Dec 2003. 101(60%) patients were with chest pain and 68(40%) were asymptomatic. Patients underwent exercise(n=6) or adenosine stress(n=163) SPECT myocardial perfusion imaging(MPI). Exclusion criteria included history of documented myocardial infarction, prior revascularization, clinically significant valvular heart disease, left-bundle branch block on rest ECG. We evaluated symptoms associated with cardiac problem and other clinical and laboratory data to reveal correlation with presence of CAD. MPI were assessed visually and semi-quantitatively with C-Equal program. Myocardial ischemia was detected in 52(31%) patients. Among them, 41 had 1-vessel and 9 had 2-vessel disease. In 52 patients with ischemia, 28(54%) were male and 24(46%) were female. 20/68(29%) asymptomatic and 32/101(32%) symptomatic patients had ischemia. Higher prevalence of neuropathy, hypertension, higher blood glucose level, HbA1c and CRP was noted in patients with myocardial ischemia. Serum levels of cholesterol and LDL was not significantly different between patients with ischemia and with normal MPI findings. Abnormal MPI findings were not related with gender and age. These results show a high prevalence of abnormal MPI results in diabetic patients regardless of symptoms. Screening stress MPI in diabetic patients should be indicated irrespective of symptoms, especially in patients with neuropathy, hypertension, higher level of blood glucose, or increased CRP.

  14. Myocardial tissue characterization in hypertrophic cardiomyopathy. Comparison between Gd-DTPA enhanced MR signal intensity ratio and myocardial biopsy

    Energy Technology Data Exchange (ETDEWEB)

    Tsukihashi, Hironori; Shimada, Toshio; Ishibashi, Yutaka [Shimane Medical Univ., Izumo (Japan)] [and others

    1995-09-01

    The aim of this study is to demonstrate whether Gd-DTPA enhanced magnetic resonance imaging (Gd-EMRI) can be used to evaluate myocardial tissue characterization. We performed Gd-EMRI in 20 patients with hypertrophic cardiomyopathy (HCM) and 6 normal controls. Ventricular myocardial biopsy was performed in 7 patients. Gd-EMRI was obtained every 10 minutes from 5 to 50 minutes after intravenous Gd-DTPA (0.1 mmol/kg) injection. Signal intensity (SI) in hypertrophic region of myocardium was measured from LV short axis image. We standardized the data according to following equations. IR (intensity ratio) =SI (myocardium) /SI (skeletal muscle). SIR=IR (in time course) /IR (before Gd-DTPA injection). SIR in HCM was delayed in time course compared with that in normal controls. Interstitial fibrosis was prominent when SIR (peak) minus SIR (40min. after) /SIR (peak) was small. The delayed decay of IR in HCM was closely related to the grade of interstitial fibrosis rather than the edema of interstitial tissue or the myocardial cell diameter. We conclude that the decay analysis with Gd-EMRI is useful to evaluate myocardial tissue characterization closely related to myocardial fibrosis in comparison with cardiac histology. (author).

  15. Estimation of anisotropy parameters using intrinsic rock properties in ...

    African Journals Online (AJOL)

    Total disregard of anisotropy in seismic velocity analysis often accounts for suboptimal imaging especially when prestack depth migration algorithm is used in depth positioning and focusing. The type of anisotropy commonly observed in most sedimentary basins, like the Niger Delta, which comprises of about 70% shale, ...

  16. Ultrasonic velocity and attenuation anisotropy of shales, Whitby, United Kingdom

    NARCIS (Netherlands)

    Zhubayev, Alimzhan; Houben, M.E.|info:eu-repo/dai/nl/370588843; Smeulders, David; Barnhoorn, A.|info:eu-repo/dai/nl/304843636

    We have conducted ultrasonic experiments, between 0.3 and 1 MHz, to measure velocity and attenuation (Q−1) anisotropy of P- and S-waves in dry Whitby Mudstone samples as a function of stress. We found the degree of anisotropy to be as large as 70% for velocity and attenuation. The sensitivity of

  17. Ultrasonic velocity and attenuation anisotropy of shales, Whitby, United Kingdom

    NARCIS (Netherlands)

    Zhubayev, A.; Houben, M.E.; Smeulders, D.M.J.; Barnhoorn, A.

    2015-01-01

    We have conducted ultrasonic experiments, between 0.3 and 1 MHz, to measure velocity and attenuation (Q?1) anisotropy of P- and S-waves in dry Whitby Mudstone samples as a function of stress. We found the degree of anisotropy to be as large as 70% for velocity and attenuation. The sensitivity of

  18. Measurement of myocardial perfusion and infarction size using computer-aided diagnosis system for myocardial contrast echocardiography.

    Science.gov (United States)

    Du, Guo-Qing; Xue, Jing-Yi; Guo, Yanhui; Chen, Shuang; Du, Pei; Wu, Yan; Wang, Yu-Hang; Zong, Li-Qiu; Tian, Jia-Wei

    2015-09-01

    Proper evaluation of myocardial microvascular perfusion and assessment of infarct size is critical for clinicians. We have developed a novel computer-aided diagnosis (CAD) approach for myocardial contrast echocardiography (MCE) to measure myocardial perfusion and infarct size. Rabbits underwent 15 min of coronary occlusion followed by reperfusion (group I, n = 15) or 60 min of coronary occlusion followed by reperfusion (group II, n = 15). Myocardial contrast echocardiography was performed before and 7 d after ischemia/reperfusion, and images were analyzed with the CAD system on the basis of eliminating particle swarm optimization clustering analysis. The myocardium was quickly and accurately detected using contrast-enhanced images, myocardial perfusion was quantitatively calibrated and a color-coded map calibrated by contrast intensity and automatically produced by the CAD system was used to outline the infarction region. Calibrated contrast intensity was significantly lower in infarct regions than in non-infarct regions, allowing differentiation of abnormal and normal myocardial perfusion. Receiver operating characteristic curve analysis documented that -54-pixel contrast intensity was an optimal cutoff point for the identification of infarcted myocardium with a sensitivity of 95.45% and specificity of 87.50%. Infarct sizes obtained using myocardial perfusion defect analysis of original contrast images and the contrast intensity-based color-coded map in computerized images were compared with infarct sizes measured using triphenyltetrazolium chloride staining. Use of the proposed CAD approach provided observers with more information. The infarct sizes obtained with myocardial perfusion defect analysis, the contrast intensity-based color-coded map and triphenyltetrazolium chloride staining were 23.72 ± 8.41%, 21.77 ± 7.8% and 18.21 ± 4.40% (% left ventricle) respectively (p > 0.05), indicating that computerized myocardial contrast echocardiography can

  19. Fractal analysis of heart rate dynamics as a predictor of mortality in patients with depressed left ventricular function after acute myocardial infarction. TRACE Investigators. TRAndolapril Cardiac Evaluation

    DEFF Research Database (Denmark)

    Mäkikallio, T H; Høiber, S; Køber, L

    1999-01-01

    A number of new methods have been recently developed to quantify complex heart rate (HR) dynamics based on nonlinear and fractal analysis, but their value in risk stratification has not been evaluated. This study was designed to determine whether selected new dynamic analysis methods of HR...

  20. Variable Azimuthal Anisotropy in Earth's Lowermost Mantle

    Science.gov (United States)

    Garnero, Edward J.; Maupin, Valérie; Lay, Thorne; Fouch, Matthew J.

    2004-10-01

    A persistent reversal in the expected polarity of the initiation of vertically polarized shear waves that graze the D'' layer (the layer at the boundary between the outer core and the lower mantle of Earth) in some regions starts at the arrival time of horizontally polarized shear waves. Full waveform modeling of the split shear waves for paths beneath the Caribbean requires azimuthal anisotropy at the base of the mantle. Models with laterally coherent patterns of transverse isotropy with the hexagonal symmetry axis of the mineral phases tilted from the vertical by as much as 20° are consistent with the data. Small-scale convection cells within the mantle above the D'' layer may cause the observed variations by inducing laterally variable crystallographic or shape-preferred orientation in minerals in the D'' layer.

  1. Competing anisotropies in holmium-erbium superlattices

    DEFF Research Database (Denmark)

    Simpson, J.A.; McMorrow, D.F.; Cowley, R.A.

    1994-01-01

    The effect of competing crystal-field anisotropies on magnetic order has been investigated in a series of Ho/Er superlattices. For temperatures in the interval T(N)(Er) less-than-or-equal-to T less-than-or-equal-to T(N)(Ho) the Ho basal-plane order propagates coherently through the paramagnetic Er...... with a typical length scale of 1000 angstrom. Below T(N)(Er) the coherence length of the basal-plane order decreases, while the longitudinal component of the Er moments fails to order across the Ho block. It is argued that these results require an extension of current models of indirect exchange in superlattices...

  2. Absolute Plate Velocities from Seismic Anisotropy

    Science.gov (United States)

    Kreemer, Corné; Zheng, Lin; Gordon, Richard

    2015-04-01

    The orientation of seismic anisotropy inferred beneath plate interiors may provide a means to estimate the motions of the plate relative to the sub-asthenospheric mantle. Here we analyze two global sets of shear-wave splitting data, that of Kreemer [2009] and an updated and expanded data set, to estimate plate motions and to better understand the dispersion of the data, correlations in the errors, and their relation to plate speed. We also explore the effect of using geologically current plate velocities (i.e., the MORVEL set of angular velocities [DeMets et al. 2010]) compared with geodetically current plate velocities (i.e., the GSRM v1.2 angular velocities [Kreemer et al. 2014]). We demonstrate that the errors in plate motion azimuths inferred from shear-wave splitting beneath any one tectonic plate are correlated with the errors of other azimuths from the same plate. To account for these correlations, we adopt a two-tier analysis: First, find the pole of rotation and confidence limits for each plate individually. Second, solve for the best fit to these poles while constraining relative plate angular velocities to consistency with the MORVEL relative plate angular velocities. The SKS-MORVEL absolute plate angular velocities (based on the Kreemer [2009] data set) are determined from the poles from eight plates weighted proportionally to the root-mean-square velocity of each plate. SKS-MORVEL indicates that eight plates (Amur, Antarctica, Caribbean, Eurasia, Lwandle, Somalia, Sundaland, and Yangtze) have angular velocities that differ insignificantly from zero. The net rotation of the lithosphere is 0.25±0.11° Ma-1 (95% confidence limits) right-handed about 57.1°S, 68.6°E. The within-plate dispersion of seismic anisotropy for oceanic lithosphere (σ=19.2° ) differs insignificantly from that for continental lithosphere (σ=21.6° ). The between-plate dispersion, however, is significantly smaller for oceanic lithosphere (σ=7.4° ) than for continental

  3. Pseudo exchange bias due to rotational anisotropy

    Energy Technology Data Exchange (ETDEWEB)

    Ehrmann, A., E-mail: andrea.ehrmann@fh-bielefeld.de [Faculty of Engineering and Mathematics, Bielefeld University of Applied Sciences, 33619 Bielefeld (Germany); Komraus, S.; Blachowicz, T.; Domino, K. [Institute of Physics – Center for Science and Education, Silesian University of Technology, 44-100 Gliwice (Poland); Nees, M.K.; Jakobs, P.J.; Leiste, H. [Karlsruhe Nano Micro Facility (KNMF), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen (Germany); Mathes, M.; Schaarschmidt, M. [ACCESS e. V., 57072 Aachen (Germany)

    2016-08-15

    Ferromagnetic nanostructure arrays with particle dimensions between 160 nm and 400 nm were created by electron-beam lithography. The permalloy structures consist of rectangular-shaped walls around a square open space. While measuring their magnetic properties using the Magneto-Optical Kerr Effect (MOKE), in some angular regions an exchange bias (EB) seemed to appear. This paper gives an overview of possible reasons for this “pseudo exchange bias” and shows experimentally and by means of micromagnetic simulations that this effect can be attributed to unintentionally measuring minor loops. - Highlights: • Pseudo exchange bias can be found in square Py nanorings of different dimensions. • Pseudo exchange bias stems from unintentionally measuring minor loops. • New approach in explaining “real” exchange bias effect in coupled FM/AFM systems. • Theoretical base to explain other measurements of a rotational anisotropy.

  4. Modeling, analysis, and visualization of anisotropy

    CERN Document Server

    Özarslan, Evren; Hotz, Ingrid

    2017-01-01

    This book focuses on the modeling, processing and visualization of anisotropy, irrespective of the context in which it emerges, using state-of-the-art mathematical tools. As such, it differs substantially from conventional reference works, which are centered on a particular application. It covers the following topics: (i) the geometric structure of tensors, (ii) statistical methods for tensor field processing, (iii) challenges in mapping neural connectivity and structural mechanics, (iv) processing of uncertainty, and (v) visualizing higher-order representations. In addition to original research contributions, it provides insightful reviews. This multidisciplinary book is the sixth in a series that aims to foster scientific exchange between communities employing tensors and other higher-order representations of directionally dependent data. A significant number of the chapters were co-authored by the participants of the workshop titled Multidisciplinary Approaches to Multivalued Data: Modeling, Visualization,...

  5. Nonaxisymmetric Anisotropy of Solar Wind Turbulence

    Science.gov (United States)

    Turner, A. J.; Gogoberidze, G.; Chapman, S. C.; Hnat, B.; Müller, W.-C.

    2011-08-01

    A key prediction of turbulence theories is frame-invariance, and in magnetohydrodynamic (MHD) turbulence, axisymmetry of fluctuations with respect to the background magnetic field. Paradoxically the power in fluctuations in the turbulent solar wind are observed to be ordered with respect to the bulk macroscopic flow as well as the background magnetic field. Here, nonaxisymmetry across the inertial and dissipation ranges is quantified using in situ observations from Cluster. The observed inertial range nonaxisymmetry is reproduced by a “fly through” sampling of a direct numerical simulation of MHD turbulence. Furthermore, fly through sampling of a linear superposition of transverse waves with axisymmetric fluctuations generates the trend in nonaxisymmetry with power spectral exponent. The observed nonaxisymmetric anisotropy may thus simply arise as a sampling effect related to Taylor’s hypothesis and is not related to the plasma dynamics itself.

  6. Myocardial involvement during the early course of type 2 diabetes mellitus: usefulness of Myocardial Performance Index

    Directory of Open Access Journals (Sweden)

    Goldoni Matteo

    2008-06-01

    Full Text Available Abstract To evaluate whether myocardial performance index detects a subclinical impairment of left ventricular systolic and diastolic function in patients with early stage of type 2 diabetes, without coronary artery disease, with or without hypertension. Furthermore, to evaluate whether some echocardiographic parameters relate to the metabolic control. Fourty-five consecutive male patients (mean age 52.5 years with type 2 diabetes mellitus of recent onset (23 hypertensives and 22 normotensives and 22 age matched healthy controls males were analysed. All participants had normal exercise ECG. All subjects underwent standard and Doppler echocardiography for the assessment of the isovolumic Doppler time interval and Doppler-derived myocardial performance index. In all diabetic patients a glycated haemoglobin test was also performed. No differences were observed in blood pressure, heart rate, and conventional echocardiographic parameters comparing the 2 subgroups of diabetic patients and the controls. Myocardial performance index was significantly higher in diabetic patients independently of the hypertension occurrence, compared to the controls (0.49 and 0.49 diabetic normotensives and hypertensives respectively vs. 0.39, p

  7. Evaluation of hemodynamic significance of coronary fistulae. Diagnostic integration between coronary angiography and stress/rest myocardial scintigraphy; Valutazione del significato emodinamico di fistole coronariche artero-venose. Integrazione diagnostica tra angiografia coronarica e scintigrafia miocardica a riposo e sotto sforzo

    Energy Technology Data Exchange (ETDEWEB)

    Rubini, G.; Sebastiani, M. [Bari Univ., Bari (Italy). Cattedra di Medicina Nucleare; Ettorre, G. C. [Foggia Univ., Foggia (Italy). Cattedra di Radiologia; Bovenzi, F. [Ospedale Policlinico, Unita' Operativa di Cardiologia, Bari (Italy)

    2000-12-01

    It is here reported on the importance of the integration of data obtained from digital coronary angiography and stress/rest {sup 99m}Tc sestamibi myocardial perfusion single photon emission tomography in evaluationing the hemodynamic significance of coronary arteriovenous fistulae. Coronary fistulae were detected with coronary angiography in 9 patients. All patients underwent clinical examination, trans thoracic echocardiography, stress electrocardiogram and stress/rest {sup 99m}Tc sestamibi myocardial perfusion single photon emission tomography. Stress/rest {sup 99m}Tc sestamibi myocardial perfusion single photon tomography and stress electrocardiogram showed stress-induced myocardial ischemia in 2 patients. The first patient with familial predisposition and risk factors for ischemic heart disease presented a mesocardic heart murmur on clinical examination. At stress ECG (125 Watt, 153 b/m max frequency 93%, arterial pressure 230 mmHg, max frequency pressure product 35200) ischemic alterations were recorded at the first minute of the second stage of the Bruce protocol. Coronary angiography detected a circumflex artery fistula in the coronary sinus. Stress/rest {sup 99m}Tc sestamibi myocardial perfusion single photon emission tomography for the evaluation of stress/rest perfusion detected a reversible perfusion defect of the proximal portion of the posterolateral and lateral walls, thus confirming the hemodynamic importance of the flow through the fistula during stress cycloergometric testing. In the second patient familial predisposition to ischemic heart disease and previous inferior wall myocardial infarction and non-significant stress ECG, coronary angiography identified a suocclusive stenosis of the right coronary artery and anomaly between the anterior interventricular artery and the left pulmonary artery. The presence of the contrast medium in the left pulmonary artery identified a flow from the left ventricle to the left pulmonary artery. Good angiographic

  8. Theoretical Compton profile anisotropies in molecules and solids. IV. Parallel--perpendicular anisotropies in alkali fluoride molecules

    Energy Technology Data Exchange (ETDEWEB)

    Matcha, R.L.; Pettitt, B.M.; Ramirez, B.I.; McIntire, W.R.

    1979-07-15

    Calculations of Compton profiles and parallel--perpendicular anisotropies in alkali fluorides are presented and analyzed in terms of molecular charge distributions and wave function character. It is found that the parallel profile associated with the valence pi orbital is the principal factor determining the relative shapes of the total profile anisotropies in the low momentum region.

  9. Conditional replaceability of magnetic surface anisotropies by effective volume anisotropies in the ferromagnetic resonance of ultrathin films

    Science.gov (United States)

    Rado, George T.

    1987-04-01

    Specific conditions are proposed for the replaceability of magnetic surface anisotropies by effective volume anisotropies and for the concomitant replaceability of the actual ferromagnetic resonance (FMR) surface mode or spin wave mode by a uniform mode. These conditions are then applied to the parallel and perpendicular FMR configurations in monocrystalline and amorphous ferromagnetic films. The significance and limitations of the results are discussed.

  10. Acute administration of epirubicin induces myocardial depression in isolated rat heart and production of radical species evaluated by electron spin resonance spectroscopy.

    Science.gov (United States)

    Delemasure, Stéphanie; Sicard, Pierre; Lauzier, Benjamin; Moreau, Daniel; Vergely, Catherine; Rochette, Luc

    2007-12-01

    The aim of our study was to evaluate the acute effect of epirubicin (EPI), an anthracycline anticancer drug, on the evolution of cardiac functional parameters and production of reactive oxygen/nitrogen species (RONS). Isolated perfused rat hearts were subjected to 70 minutes of EPI (10.3 microM) infusion and to 5 minutes of isoproterenol (ISO, 0.1 microM) at the end of the protocol. Coronary flow (CF), left ventricular developed pressure (LVDP), and lactate dehydrogenase (LDH) release in the coronary effluents were evaluated throughout the protocol. RONS were detected in the coronary effluents by electron spin resonance spectroscopy with a spin probe, 1-hydroxy-3-carboxy-pyrrolidine (CP-H, 0.1 mM). EPI induced a reduction in CF and in LVDP (P now needed to determine whether new cardioprotective agents targeting oxidative stress may reduce the incidence of anthracycline-induced cardiotoxicity.

  11. Measurements of Seismic Anisotropy in Synthetic Rocks with Controlled Crack Geometry and Different Crack Densities

    Science.gov (United States)

    Ding, Pinbo; Di, Bangrang; Wang, Ding; Wei, Jianxin; Li, Xiangyang

    2017-05-01

    Seismic anisotropy can help to extract azimuthal information for predicting crack alignment, but the accurate evaluation of cracked reservoir requires knowledge of degree of crack development, which is achieved through determining the crack density from seismic or VSP data. In this research we study the dependence of seismic anisotropy on crack density, using synthetic rocks with controlled crack geometries. A set of four synthetic rocks containing different crack densities is used in laboratory measurements. The crack thickness is 0.06 mm and the crack diameter is 3 mm in all the cracked rocks, while the crack densities are 0.00, 0.0243, 0.0486, and 0.0729. P and S wave velocities are measured by an ultrasonic investigation system at 0.5 MHz while the rocks are saturated with water. The measurements show the impact of crack density on the P and S wave velocities. Our results are compared to the theoretical prediction of Chapman (J App Geophys 54:191-202, 2003) and Hudson (Geophys J R Astron Soc 64:133-150, 1981). The comparison shows that measured velocities and theoretical results are in good quantitative agreement in all three cracked rocks, although Chapman's model fits the experimental results better. The measured anisotropy of the P and S wave in the four synthetic rocks shows that seismic anisotropy is directly proportional to increasing crack density, as predicted by several theoretical models. The laboratory measurements indicate that it would be effective to use seismic anisotropy to determine the crack density and estimate the intensity of crack density in seismology and seismic exploration.

  12. Modal investigation of elastic anisotropy in shallow-water environments: anisotropy beyond vertical transverse isotropy.

    Science.gov (United States)

    Soukup, Darin J; Odom, Robert I; Park, Jeffrey

    2013-07-01

    Theoretical and numerical results are presented for modal characteristics of the seismo-acoustic wavefield in anisotropic range-independent media. General anisotropy affects the form of the elastic-stiffness tensor, particle-motion polarization, the frequency and angular dispersion curves, and introduces near-degenerate modes. Horizontally polarized particle motion (SH) cannot be ignored when anisotropy is present for low-frequency modes having significant bottom interaction. The seismo-acoustic wavefield has polarizations in all three coordinate directions even in the absence of any scattering or heterogeneity. Even weak anisotropy may have a significant impact on seismo-acoustic wave propagation. Unlike isotropic and transversely isotropic media with a vertical symmetry axis where acoustic signals comprise P-SV modes alone (in the absence of any scattering), tilted TI media allow both quasi-P-SV and quasi-SH modes to carry seismo-acoustic energy. Discrete modes for an anisotropic medium are best described as generalized P-SV-SH modes with polarizations in all three Cartesian directions. Conversion to SH is a loss that will mimic acoustic attenuation. An in-water explosion will excite quasi-SH.

  13. Myocardial indium-111-antimyosin uptake in essential hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Uenlue, M.; Temiz, N.H. [Dept. of Nuclear Medicine, Dept. of Nuclear Medicine, Ankara (Turkey); Cengel, A. [Dept. of Cardiology, Gazi Univ. School of Medicine, Dept. of Nuclear Medicine, Ankara (Turkey)

    2003-06-01

    Aim: Evaluation of myocardial uptake of {sup 111}In-antimyosin antibodies in patients with essential hypertension for the verification of our hypothesis that it may increase in stage 1 in the left ventricle as a result of myocardial damage. Patients, methods: Twelve men (mean age: 59 {+-} 2.4 years) suffering from angina like symptoms and essential hypertension in clinical stage 1 according to the JNC-VI criteria were included into the study. These patients showed normal perfusion as revealed by thallium-201 myocardial study and coronary angiography. Left ventricular mass index was determined in echocardiography. Planar antimyosin images were obtained 48 h after the intravenous injection of the tracer. Heart to lung ratios were calculated as a parameter of myocardial tracer uptake using appropriate region of interests; values >1.52 were considered as abnormal. Results: We observed increased antimyosin uptake (mean: 1.71 {+-} 0.12) consistent with myocardial damage in 11 of 12 patients. Nine of 12 patients had a left ventricular hypertrophy with left ventricular mass index values (mean: 131 g/m{sup 2} {+-} 9.48) above 115 g/m{sup 2}. Heart to lung ratio was correlated significantly to left ventricular mass index (r = 0.902, p <0.001) and duration of hypertension (r = 0.948, p <0.001). Conclusion: Our results suggest that {sup 111}In-antimyosin imaging may indicate myocyte damage in early phases of hypertensive heart disease. (orig.)

  14. Effect of long-term cholesterol-lowering treatment with HMG-CoA reductase inhibitor (Simvastatin) of myocardial perfusion evaluated by thallium-201 single photon emission computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hosokawa, Ryohei; Nohara, Ryuji; Linxue, Li; Sasayama, Shigetake [Kyoto Univ. (Japan). Graduate School of Medicine; Tamaki, Shunichi; Hashimoto, Tetsuo; Tanaka, Masahiro; Miki, Shinji

    2000-03-01

    Fifteen patients with either angina pectoris or old myocardial infarction, who had positive {sup 201}Tl single photon emission computed tomography (SPECT) imaging and coronary sclerosis of more than 50%, were treated with an HMG-CoA reductase inhibitor (simvastatin) for more than 1 year. They were compared with an untreated control group (n=25). Total cholesterol decreased 22% and high-density lipoprotein (HDL) increased 9% with simvastatin; both changes were significantly different from those in controls. Long-term simvastatin induced improvement of myocardial perfusion on {sup 201}Tl SPECT images both during exercise and at rest, which was also significantly different from controls. In addition, the improvement of myocardial perfusion on {sup 201}Tl SPECT images was clearly related to the improvements in cholesterol values, especially nonHDL cholesterol. Thus, the greater the decrease in nonHDL cholesterol, the greater the improvement in myocardial perfusion at rest or during exercise with long-term treatment using an HMG-CoA reductase inhibitor. These findings indicate that the improvements in cholesterol values caused by HMG-CoA reductase inhibitor therapy are related to improvements of myocardial perfusion seen on {sup 201}Tl SPECT images. (author)

  15. Exchange anisotropy of ferromagnetic/antiferromagnetic bilayers intrinsic magnetic anisotropy of antiferromagnetic layer and single spin ensemble model

    CERN Document Server

    Tsunoda, M

    2002-01-01

    The origin of the magnetic anisotropy of the antiferromagnetic (AF) layer and the role of it in the magnetization process of exchange coupled ferromagnetic/antiferromagnetic bilayers are discussed. Through the magnetic torque analysis of a pseudo-single crystalline Ni-Fe/Mn-Ni bilayer and a polycrystalline Ni-Fe/Mn-Ir bilayer, the magnetocrystalline anisotropy of the antiferromagnet is strongly suggested to be the origin of the magnetic anisotropy of the antiferromagnetic (AF) layer. The single spin ensemble model is newly introduced for polycrystalline bilayers, taking into account the two-dimensionally random distribution of the magnetic anisotropy axes of the AF grains. The mechanism of a well-known experimental fact, the reversible induction of the exchange anisotropy along desirable directions by field cooling procedure, is successfully elucidated with the new model.

  16. Induced pluripotent stem cells for post myocardial infarction repair

    OpenAIRE

    Rosa Fernández, Eduardo de la

    2016-01-01

    The aim of this review is to study translational aspects of induced pluripotent stem cell technology in cardiac repair after myocardial infarction. This will be achieved by illustrating the current state of the art of this technology and, furthermore, by evaluating the limitations for clinical traslation.

  17. Left ventricular global longitudinal strain in acute myocardial infarction

    DEFF Research Database (Denmark)

    Ersbøll, Mads

    Systolic dysfunction, clinical heart failure and elevated levels of neurohormonal peptides are major predictors of adverse outcome after acute myocardial infarction (MI). In the present thesis we evaluated global longitudinal strain (GLS) in patients with acute MI in relation to neurohormonal...

  18. Thrombolytic therapy preserves vagal activity early after acute myocardial infarction

    DEFF Research Database (Denmark)

    Lind, P; Hintze, U; Møller, M

    2001-01-01

    OBJECTIVE: The purpose of this study was to evaluate the effects of thrombolytic therapy on vagal tone after acute myocardial infarction (AMI). DESIGN: Holter monitoring for 24 h was performed at hospital discharge and 6 weeks after AMI in 74 consecutive male survivors of a first AMI, who fulfilled...

  19. Myocardial defect detection using PET-CT: phantom studies.

    Directory of Open Access Journals (Sweden)

    Eugene S Mananga

    Full Text Available It is expected that both noise and activity distribution can have impact on the detectability of a myocardial defect in a cardiac PET study. In this work, we performed phantom studies to investigate the detectability of a defect in the myocardium for different noise levels and activity distributions. We evaluated the performance of three reconstruction schemes: Filtered Back-Projection (FBP, Ordinary Poisson Ordered Subset Expectation Maximization (OP-OSEM, and Point Spread Function corrected OSEM (PSF-OSEM. We used the Channelized Hotelling Observer (CHO for the task of myocardial defect detection. We found that the detectability of a myocardial defect is almost entirely dependent on the noise level and the contrast between the defect and its surroundings.

  20. The relationship between magnetic anisotropy, rock-strength anisotropy and vein emplacement in gold-bearing metabasalts of Gadag (South India)

    Science.gov (United States)

    Vishnu, C. S.; Lahiri, Sivaji; Mamtani, Manish A.

    2018-01-01

    In this study the importance of rock strength and its anisotropy in controlling vein emplacement is evaluated by integrating anisotropy of magnetic susceptibility (AMS) with rock mechanics data from massive (visibly isotropic) metabasalts of Gadag region (Dharwar Craton, South India). Orientation of magnetic foliation (MF) is first recognized from AMS. Subsequently, rock mechanics tests viz. ultrasonic P-wave velocity (Vp), uniaxial compressive strength (UCS) and point load strength (Is(50)) are done in cores extracted parallel and perpendicular to MF. Vp is found to be higher in direction parallel to MF than perpendicular to it. In contrast rock strength (UCS and Is(50)) is greater in direction perpendicular to MF, than parallel to it. This proves that rocks from the gold mineralized belt of Gadag have rock strength anisotropy. Orientation of MF in Gadag region is NW-SE, which is also the mean orientation of quartz veins. Previous studies indicate that emplacement of veins in the region took place during regional D3 (NW-SE shortening). Based on the present study, it is concluded that vein emplacement took place in NW-SE orientation because the rocks have strength anisotropy and are weaker in this direction (orientation of MF), which dilated to accommodate fluid flow. In addition, vein intensities are measured along three traverses and found to be variable. It is argued that since mineralization is favoured when the system gets saturated with fluid, variation in fluid flow could not have been responsible for variation in vein intensities in the study area. Since the rock strength of the different blocks investigated here is not uniform, it is envisaged that variation in rock strength played an important role in controlling the vein intensities. It is concluded that rock strength variation controlled strain partitioning and channelized fluid flow thus influencing vein emplacement and mineralization and formation of lodes.

  1. Angiographic assessment of reperfusion in acute myocardial infarction by myocardial blush grade

    NARCIS (Netherlands)

    Henriques, JPS; Zijlstra, F; van 't Hof, AWJ; de Boer, MJ; Gosselink, M; Hoorntje, JCA; Suryapranata, H; Dambrink, Jan Hendrik Everwijn

    2003-01-01

    Background-Angiographic successful reperfusion in acute myocardial infarction has been defined as TIMI 3 flow. However, TIMI 3 flow does not always result in effective myocardial reperfusion. Myocardial blush grade (MBG) is an angiographic measure of myocardial perfusion. We hypothesized that

  2. Angiographic assessment of reperfusion in acute myocardial infarction by myocardial blush grade

    NARCIS (Netherlands)

    Henriques, Jose P. S.; Zijlstra, Felix; van 't Hof, Arnoud W. J.; de Boer, Menko-Jan; Dambrink, Jan-Henk E.; Gosselink, Marcel; Hoorntje, Jan C. A.; Suryapranata, Harry

    2003-01-01

    Angiographic successful reperfusion in acute myocardial infarction has been defined as TIMI 3 flow. However, TIMI 3 flow does not always result in effective myocardial reperfusion. Myocardial blush grade (MBG) is an angiographic measure of myocardial perfusion. We hypothesized that optimal

  3. Myocardial infarction in children: Two interesting cases

    Directory of Open Access Journals (Sweden)

    Suryawanshi Suresh

    2011-01-01

    Full Text Available Myocardial infarction in children is extremely rare and can have various etiologies. The following two case reports highlight rare but important causes of myocardial infarction in children.

  4. Left ventricular hypertrophy is associated with increased infarct size and decreased myocardial salvage in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

    DEFF Research Database (Denmark)

    Nepper-Christensen, Lars; Lønborg, Jacob; Ahtarovski, Kiril Aleksov

    2017-01-01

    Background--Approximately one third of patients with ST-segment elevation myocardial infarction (STEMI) have left ventricular hypertrophy (LVH), which is associated with impaired outcome. However, the causal association between LVH and outcome in STEMI is unknown. We evaluated the association...... between LVH and: myocardial infarct size, area at risk, myocardial salvage, microvascular obstruction, left ventricular (LV) function (all determined by cardiac magnetic resonance [CMR]), and all-cause mortality and readmission for heart failure in STEMI patients treated with primary percutaneous coronary...

  5. Compound danshen dripping pills modulate the perturbed energy metabolism in a rat model of acute myocardial ischemia

    OpenAIRE

    Jiahua Guo; Yonghong Yong; Jiye Aa; Bei Cao; Runbin Sun; Xiaoyi Yu; Jingqiu Huang; Na Yang; Lulu Yan; Xinxin Li; Jing Cao; Nan Aa; Zhijian Yang; Xiangqing Kong; Liansheng Wang

    2016-01-01

    The continuous administration of compound danshen dripping pills (CDDP) showed good efficacy in relieving myocardial ischemia clinically. To probe the underlying mechanism, metabolic features were evaluated in a rat model of acute myocardial ischemia induced by isoproterenol (ISO) and administrated with CDDP using a metabolomics platform. Our data revealed that the ISO-induced animal model showed obvious myocardial injury, decreased energy production, and a marked change in metabolomic patter...

  6. Stem cell mobilization by granulocyte colony-stimulating factor for myocardial recovery after acute myocardial infarction: a meta-analysis

    DEFF Research Database (Denmark)

    Zohlnhofer, D.; Dibra, A.; Koppara, T.

    2008-01-01

    OBJECTIVES: The objective of this meta-analysis was to evaluate the effect of stem cell mobilization by granulocyte colony-stimulating factor (G-CSF) on myocardial regeneration on the basis of a synthesis of the data generated by randomized, controlled clinical trials of G-CSF after acute...

  7. Magnetic anisotropy of ultrafine 316L stainless steel fibers

    Energy Technology Data Exchange (ETDEWEB)

    Shyr, Tien-Wei, E-mail: twshyr@fcu.edu.tw [Department of Fiber and Composite Materials, Feng Chia University, No. 100, Wenhwa Road, Seatwen, Taichung 40724, Taiwan, ROC (China); Huang, Shih-Ju [Department of Fiber and Composite Materials, Feng Chia University, No. 100, Wenhwa Road, Seatwen, Taichung 40724, Taiwan, ROC (China); Wur, Ching-Shuei [Department of Physics, National Cheng Kung University, No. 1, University Road, Tainan 70101, Taiwan, ROC (China)

    2016-12-01

    An as-received 316L stainless steel fiber with a diameter of 20 μm was drawn using a bundle drawing process at room temperature to form ultrafine stainless steel fibers with diameters of 12, 8, and 6 μm. The crystalline phases of the fibers were analyzed using the X-ray diffraction (XRD) profile fitting technique. The grain sizes of γ-austenite and α′-martensite were reduced to nanoscale sizes after the drawing process. XRD analysis and focused ion beam-scanning electron microscope observations showed that the newly formed α′-martensitic grains were closely arrayed in the drawing direction. The magnetic property was measured using a superconducting quantum interference device vibrating sample magnetometer. The magnetic anisotropy of the fibers was observed by applying a magnetic field parallel and perpendicular to the fiber axis. The results showed that the microstructure anisotropy including the shape anisotropy, magnetocrystalline anisotropy, and the orientation of the crystalline phases strongly contributed to the magnetic anisotropy. - Highlights: • The martensitic transformation of the 316L SS fiber occurred during the cold drawn. • The grain sizes of γ-austenite and α′-martensite were reduced to the nanoscale. • The newly formed martensitic grains were closely arrayed in the drawing direction. • The drawing process caused the magnetic easy axis to be aligned with the fiber axis. • The microstructure anisotropy strongly contributed to the magnetic anisotropy.

  8. A study of partial volume effect on SPECT imaging using myocardial phantom. With HCM (ASH) model myocardial phantom

    Energy Technology Data Exchange (ETDEWEB)

    Onoguchi, Masahisa [Kanazawa Univ. (Japan). School of Medicine

    1997-05-01

    In order to evaluate simultaneously both myocardial perfusion and regional wall motion using ECG-gated myocardial SPECT imaging, correction for the partial volume effect (PVE) should be performed. For the quantitative analysis of myocardial SPECT imaging in patients with hypertrophic cardiomyopathy (HCM), we formed a new phantom simulating HCM with various septal wall thicknesses and estimated PVE using the recovery coefficient (RC). The value of RC in all phantoms increased with increasing thickness of the septal wall reaching a plateau at 25 mm for the cylindrical phantom and 25 mm for the Ep-phantom. Compared with the RC value, the PMMA-phantom had little influence on PVE. Therefore, our results suggested that the count in the septal wall could be underestimated if PVE was corrected by the value obtained for the cylindrical phantom. In conclusion, our new phantom simulating HCM was useful in assessing PVE in the hypertrophic septal wall. (author)

  9. Dynamic CT myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Caruso, Damiano [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiological Sciences, Oncological and Pathological Sciences, University of Rome “Sapienza”, Latina (Italy); Eid, Marwen [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Schoepf, U. Joseph, E-mail: schoepf@musc.edu [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC (United States); Jin, Kwang Nam [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Radiology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul (Korea, Republic of); Varga-Szemes, Akos [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Tesche, Christian [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Cardiology and Intensive Care Medicine, Heart Center Munich-Bogenhausen, Munich (Germany); Mangold, Stefanie [Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC (United States); Department of Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Tuebingen (Germany); and others

    2016-10-15

    Highlights: • CT myocardial perfusion provides functional assessment of the myocardium. • CCTA is limited in determining the hemodynamic significance of coronary stenosis. • CT-MPI can accurately detect hemodynamically significant coronary artery stenosis. - Abstract: Non-invasive cardiac imaging has rapidly evolved during the last decade due to advancements in CT based technologies. Coronary CT angiography has been shown to reliably assess coronary anatomy and detect high risk coronary artery disease. However, this technique is limited to anatomical assessment, thus non-invasive techniques for functional assessment of the heart are necessary. CT myocardial perfusion is a new CT based technique that provides functional assessment of the myocardium and allows for a comprehensive assessment of coronary artery disease with a single modality when combined with CTA. This review aims to discuss dynamic CT myocardial perfusion as a new technique in the assessment of CAD.

  10. Clinical usefulness of myocardial scintigraphy for diagnosis of ischemic heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Tsuji, Sotoyuki; Murakami, Eiji; Takekoshi, Noboru (Kanazawa Medical Univ. (Japan))

    1983-03-01

    Methods for noninvasive diagnosis an evaluation of coronary artery disease have been dramatically advanced by the development of myocardial scintigraphy. In this paper, 225 patients with coronary artery disease were studied with the following results: (1) With the use of 99mTc-PYP acute myocardial infarction areas were successfully detected in 80 % of the patients. (2) In the detection of myocardial infarction coincidence of the location of scan site defined by electrocardiogram with that of thallium defect at rest was 72 %. Coincidence of the area of dyssynergy in left ventriculogram with the site of thallium defect was 79 %. (3) The sensitivity of thallium-201 myocardial scintigram was 54 % and the specificity was 82 % in detecting angina pectoris. In detecting myocardial infarction the sensitivity was 81 % and the specificity was 75 %. In LCX the sensitivity of thallium-201 decreased considerably. (4) The sensitivity and specificity of thallium-201 imaging in detection of coronary artery disease after exercise were 78 % and 63 %, respectively.

  11. Optimizing Evaluation of Patients with Low-to-Intermediate-Risk Acute Chest Pain: A Randomized Study Comparing Stress Myocardial Perfusion Tomography Incorporating Stress-Only Imaging Versus Cardiac CT.

    Science.gov (United States)

    Nabi, Faisal; Kassi, Mahwash; Muhyieddeen, Kamil; Chang, Su Min; Xu, Jiaqiong; Peterson, Leif E; Wray, Nelda P; Shirkey, Beverly A; Ashton, Carol M; Mahmarian, John J

    2016-03-01

    The purpose of this study was to determine whether stress myocardial perfusion (SPECT) optimized with stress-only (SO) imaging is comparable to cardiac CT angiography (CTA) for evaluating patients with acute chest pain (ACP). This was a prospective randomized observational study in 598 ACP patients who underwent CTA versus SPECT. The primary endpoint was length of hospital stay, and secondary endpoints were test feasibility, time to diagnosis, diagnostic accuracy, radiation exposure, and overall cost. Median follow-up was 6.5 mo, with a 3.8% cardiac event rate defined as death or an acute coronary syndrome. Of 2,994 patients screened, 1,703 (56.9%) were not candidates for CTA because of prior cardiac disease (41%) or imaging contraindications (16%). Time to diagnosis (8.1 ± 8.5 vs. 9.4 ± 7.4 h) and length of hospital stay (19.7 ± 27.8 vs. 23.5 ± 34.4 h) were significantly shorter with CTA than with SPECT (P = 0.002). However, time to diagnosis (7.0 ± 6.2 vs. 6.8 ± 5.9 h, P = 0.20), length of stay (15.5 ± 17.2 vs. 16.7 ± 15.3 h, P = 0.36), and hospital costs ($4,242 ± $3,871 vs. $4,364 ± 1781, P = 0.86) were comparable with CTA versus SO SPECT, respectively. SO was also superior to conventional SPECT regarding all of the above metrics and significantly reduced radiation exposure (5.5 ± 4.4 vs. 12.5 ± 2.7 mSv, P emergency room patients who are a population likely to have a normal test result. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  12. Design and reliability of a specific instrument to evaluate patient safety for patients with acute myocardial infarction treated in a predefined care track: a retrospective patient record review study in a single tertiary hospital in the Netherlands.

    Science.gov (United States)

    Eindhoven, Daniëlle C; Borleffs, C Jan Willem; Dietz, Marlieke F; Schalij, Martin J; Brouwers, Corline; de Bruijne, Martine C

    2017-03-20

    Numerous studies have shown that a substantial number of patients suffer from adverse events (AEs) as a result of hospital care. However, specific data on AEs in acute cardiac care are scarce. The current manuscript describes the development and validation of a specific instrument to evaluate patient safety of a predefined care track for patients with acute myocardial infarction (AMI). Retrospective patient record review study. A total of 879 hospital admissions treated in a tertiary care centre for an AMI (age 64±12 years, 71% male). In the first phase, the medical records of patients with AMI warranting coronary angiography or coronary intervention were analysed for process deviations. In the second phase, the medical records of these patients were checked for any harm that had occurred which was caused by the healthcare provider or the healthcare organisation (AE) and whether the harm that occurred was preventable. Of all 879 patients included in the analysis, 40% (n=354) had 1 or more process deviation. Of these 354 patients, 116 (33%) had an AE. Patients with AE experienced more process deviations compared with patients without AE (2±1.7 vs 1.5±0.9 process deviations per patient, p=0.005). Inter-rater reliability in assessing a causal relation of healthcare with the origin of an AE showed a κ of 0.67 (95% CI 0.51 to 0.83). This study shows that it is possible to develop a reliable method, which can objectively assess process deviations and the occurrence of AEs in a specified population. This method could be a starting point for developing an electronic tracking system for continuous monitoring in strictly predefined care tracks. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  13. Exenatide reduces reperfusion injury in patients with ST-segment elevation myocardial infarction

    DEFF Research Database (Denmark)

    Lønborg, Jacob; Vejlstrup, Niels Grove; Kelbæk, Henning Skov

    2011-01-01

    Aims Exenatide, a glucagon-like-peptide-1 analogue, increases myocardial salvage in experimental settings with coronary occlusion and subsequent reperfusion. We evaluated the cardioprotective effect of exenatide at the time of reperfusion in patients with ST-segment elevation myocardial infarction...... and maintained for 6 h after the procedure. The primary endpoint was salvage index calculated from myocardial area at risk (AAR), measured in the acute phase, and final infarct size measured 90 ± 21 days after pPCI by cardiac magnetic resonance (CMR). In 105 patients evaluated with CMR, a significantly larger...

  14. Impact of obesity on long-term prognosis following acute myocardial infarction

    DEFF Research Database (Denmark)

    Kragelund, Charlotte; Hassager, Christian; Hildebrandt, Per

    2005-01-01

    OBJECTIVE: To evaluate the impact of obesity on mortality in patients with acute myocardial infarction. METHODS: This study comprises 6676 consecutive patients with acute myocardial infarction screened for entry into the Danish Trandolapril Cardiac Evaluation (TRACE) study. At baseline, body mass.......01)]. Increasing WHR in women showed a trend of increased mortality, although this was not significant [adjusted RR=1.13 (0.95-1.34, p=0.2)]. CONCLUSION: In patients with acute myocardial infarction overall obesity as assessed by body mass index is inversely related to mortality. However, abdominal obesity appears...

  15. Crustal radial anisotropy beneath Cameroon from ambient noise tomography

    Science.gov (United States)

    Ojo, Adebayo Oluwaseun; Ni, Sidao; Li, Zhiwei

    2017-01-01

    To increase the understanding of crustal deformation and crustal flow patterns due to tectonic processes in Cameroon, we study the lateral variability of the crustal isotropic velocity and radial anisotropy estimated using Ambient Noise Tomography (ANT). Rayleigh and Love wave Noise Correlation Functions (NCFs) were retrieved from the cross-correlation of seismic ambient noise data recorded in Cameroon, and phase velocities at periods of 8 to 30 s were measured to perform surface wave tomography. Joint inversion of Rayleigh and Love wave data for isotropic velocity models could not fit the observed dispersions simultaneously. We attribute the Love-Rayleigh discrepancy to the presence of radial anisotropy in the crust and estimated its magnitude. Our 3-D radial anisotropic model reveals the spatial variation of strong to weak positive (Vsh > Vsv) and negative (Vsv > Vsh) radial anisotropy in the crust. We observe negative radial anisotropy in the upper crust that is associated mainly with the location of a previously reported mantle plume. The anisotropy could be attributed to the vertical alignment of fossil microcracks or metamorphic foliations due to the upwelling of plume material. A strong positive radial anisotropy is centered at the location of an inferred boundary between the Congo Craton and the Oubanguides Belt that might be related to the preferred orientation of crustal anisotropic minerals associated with shearing in this fault zone. The middle crust is characterized by a widespread negative radial anisotropy that is likely caused by the flow-induced alignment of anisotropic minerals that crystallized during magma intrusion. The magnitude of the radial anisotropy varies systematically from predominantly negative in the middle crust to positive in the lower crust. The imaged patterns of the isotropic velocity and radial anisotropy are consistent with previous studies and agree with regional tectonics.

  16. Cardiac metabolism in myocardial ischemia.

    Science.gov (United States)

    Rosano, Giuseppe M C; Fini, Massimo; Caminiti, Giuseppe; Barbaro, Giuseppe

    2008-01-01

    Myocardial ischemia occurs for a mismatch between blood flow and metabolic requirements, when the rate of oxygen and metabolic substrates delivery to the myocardium is insufficient to meet the myocardial energy requirements for a given myocardial workload. During ischemia, substantial changes occur in cardiac energy metabolism, as a consequence of the reduced oxygen availability. Some of these metabolic changes are beneficial and may help the heart adapt to the ischemic condition. However, most of the changes are maladaptive and contribute to the severity of the ischemic injury leading stunned or hibernating myocardium, cell death and ultimately to contractile disfunction. Dramatic changes in cardiac metabolism and contractile function, also occur during myocardial reperfusion as a consequence of the generation of oxygen free radicals, loss of cation homeostasis, depletion of energy stores, and changes in subcellular activities. The reperfusion injury may cause in the death of cardiac myocytes that were still viable immediately before myocardial reperfusion. This form of myocardial injury, by itself can induce cardiomyocyte death and increase infarct size. During acute ischemia the relative substrate concentration is the prime factor defining preference and utilization rate. Allosteric enzyme regulation and protein phosphorylation cascades, partially controlled by hormones such as insulin, modulate the concentration effect; together they provide short-term adjustments of cardiac energy metabolism. The expression of metabolic genes is also dynamically regulated in response to developmental and (patho)physiological conditions, leading to long-term adjustments. Specific nuclear receptor transcription factors and co-activators regulate the expression of these genes. Understanding the functional role of these changes is critical for developing the concept of metabolic intervention for heart disease. The paper will review the alterations in energy metabolism that occur

  17. Morphological aspects of myocardial bridges

    Directory of Open Access Journals (Sweden)

    Almira Lujinović

    2013-11-01

    Full Text Available Although some myocardial bridges can be asymptomatic, their presence often causes coronary disease either through direct compression of the “tunnel” segment or through stimulation and accelerated development of atherosclerosis in the segment proximally to the myocardial bridge. The studied material contained 30 human hearts received from the Department of Anatomy. The hearts were preserved 3 to 5 days in 10% formalin solution. Thereafter, the fatty tissue was removed and arterial blood vessels prepared by careful dissection with special reference to the presence of the myocardial bridges. Length and thickness of the bridges were measured by the precise electronic caliper. The angle between the myocardial bridge fibre axis and other axis of the crossed blood vessel was measured by a goniometer. The presence of the bridges was confirmed in 53.33% of the researched material, most frequently (43.33% above the anterior interventricular branch. The mean length of the bridges was 14.64±9.03 mm and the mean thickness was 1.23±1.32 mm. Myocardial bridge fibres pass over the descending blood vessel at the angle of 10-90 degrees. The results obtained on a limited sample suggest that the muscular index of myocardial bridge is the highest for bridges located on RIA, but that the difference is not significant in relation to bridges located on other branches. The results obtained suggest that bridges located on other branches, not only those on RIA, could have a great contractive power and, consequently, a great compressive force, which would be exerted on the wall of a crossed blood vessel.

  18. Myocardial dysfunction in malnourished children

    Directory of Open Access Journals (Sweden)

    Faddan Nagla Hassan

    2010-01-01

    Full Text Available Background : Malnourished children suffer several alterations in body composition that could produce cardiac abnormalities. Aim : The aim of the present study was to detect the frequency of myocardial damage in malnourished children as shown by echocardiography and cardiac troponin T (cTnT level. Methods : Forty-five malnourished infants and young children (mean±SD of age was 11.24 ±7.88 months were matched with 25 apparently healthy controls (mean±SD of age was 10.78±6.29 months. Blood sample was taken for complete blood picture, liver and kidney function tests, serum sodium, potassium, calcium levels and cTnT. All the malnourished children were subjected to echocardiographic evaluation. Results : Malnourished children showed a significantly lower left ventricular (LV mass than the control group. The LV systolic functions were significantly impaired in patients with severe malnutrition. The cTnT level was higher than the upper reference limits in 11 (24.44% of the studied malnourished children and all of them had a severe degree of malnutrition. The cTnT level was significantly higher in patients with anemia, sepsis and electrolyte abnormalities and it correlated negatively with LV ejection fraction (EF. Six of the studied children with high cTnT levels (54.5% died within 21 days of treatment while only one case (2.9% with normal level of cTnT died within the same period. Conclusions: LV mass is reduced in malnourished children. Children with severe malnutrition have a significant decrease in LV systolic functions. Elevated cTnT levels in malnourished children has both diagnostic and prognostic significance for cardiomyocyte damage.

  19. Risk factors for near-term myocardial infarction in apparently healthy men and women

    DEFF Research Database (Denmark)

    Nordestgaard, Børge; Adourian, Aram S; Freiberg, Jacob Johannes von S

    2010-01-01

    Limited information is available regarding risk factors for the near-term (4 years) onset of myocardial infarction (MI). We evaluated established cardiovascular risk factors and putative circulating biomarkers as predictors for MI within 4 years of measurement....

  20. Somatic symptom overlap in Beck Depression Inventory-II scores following myocardial infarction

    NARCIS (Netherlands)

    Thombs, Brett D.; Ziegelstein, Roy C.; Pilote, Louise; Dozois, David J. A.; Beck, Aaron T.; Dobson, Keith S.; Fuss, Samantha; de Jonge, Peter; Grace, Sherry L.; Stewart, Donne E.; Ormel, Johan; Abbey, Susan E.

    Background Depression measures that include somatic symptoms may inflate severity estimates among medically ill patients, including those with cardiovascular disease. Aims To evaluate whether people receiving in-patient treatment following acute myocardial infarction (AMI) had higher somatic symptom

  1. Prognostic association of cardiac anxiety with new cardiac events and mortality following myocardial infarction

    NARCIS (Netherlands)

    Van Beek, Maria H. C. T.; Zuidersma, Marij; Lappenschaar, Martijn; Pop, Gheorghe; Roest, Annelieke M.; Van Balkom, Anton J. L. M.; Speckens, Anne E. M.; Oude Voshaar, Richard C.

    2016-01-01

    Background General anxiety and depressive symptoms following a myocardial infarction are associated with a worse cardiac prognosis. However, the contribution of specific aspects of anxiety within this context remains unclear. Aims To evaluate the independent prognostic association of cardiac anxiety

  2. Experimental Approaches to Acute Myocardial Infarction

    NARCIS (Netherlands)

    D.B. Uitterdijk (André)

    2015-01-01

    markdownabstractAbstract This thesis is dedicated to i) novel methods and optimization studies to improve the diagnosis of myocardial ischemia and myocardial infarction as well as fundamental studies that precede novel therapies for myocardial infarction. In part ii) 2 novel, adjunctive therapies

  3. Scintigraphic findings in myocardial infarction

    Energy Technology Data Exchange (ETDEWEB)

    Schuemichen, C.; Krause, T.

    1988-09-01

    Radioisotope studies are currently used mainly to assess the individual risk before and after myocardial infarction (MI). Scintigraphy will be used increasingly to diagnose and localize acute myocardial infarction (AMI), to measure the infarct size and to detect reperfusion, whether spontaneous or after lysis, in the infarct area. High sensitivity and specificity are obtained by using tomographic imaging modalities and by the combined and simultaneous use of markers for perfusion and necrosis. This technique allows recognition even of nontransmural infarctions, involvement of the right ventricle, subendocardial necroses, and ischemic injuries in unstable angina pectoris.

  4. Aid in the detection of myocardial perfusion abnormality utilizing SPECT atlas and images registration: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Padua, Rodrigo Donizete Santana de [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Div. de Cardiologia]. E-mail: rodrigo_dsp@hcrp.fmrp.usp.br; Oliveira, Lucas Ferrari de [Universidade Federal de Pelotas (UFPel), RS (Brazil). Inst. de Fisica e Matematica. Dept. de Tecnologia da Informacao; Marques, Paulo Mazzoncini de Azevedo [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Centro de Ciencias das Imagens e Fisica Medica; Groote, Jean-Jacques Georges Soares de [Instituto de Ensino Superior COC, Ribeirao Preto, SP (Brazil). Lab. of Artifical Intelligence and Applications; Castro, Adelson Antonio de [Universidade de Sao Paulo (USP), Ribeirao Preto, SP, (Brazil). Faculdade de Medicina; Ana, Lauro Wichert [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Medicina. Centro de Ciencias das Imagens e Fisica Medica; Simoes, Marcus Vinicius [Universidade de Sao Paulo (USP), Ribeirao Preto, SP, (Brazil). Faculdade de Medicina. Divisao de Cardiologia

    2008-11-15

    To develop an atlas of myocardial perfusion scintigraphy and evaluating its applicability in computer-aided detection of myocardial perfusion defects in patients with ischemic heart disease. The atlas was created with rest-stress myocardial perfusion scintigraphic images of 20 patients of both genders with low probability of coronary artery disease and considered as normal by two experienced observers. Techniques of image registration and mathematical operations on images were utilized for obtaining template images depicting mean myocardial uptake and standard deviation for each gender and physiological condition. Myocardial perfusion scintigraphy images of one male and one female patient were aligned with the corresponding atlas template image, and voxels with myocardial uptake rates two standard deviations below the mean voxel value of the respective region in the atlas template image were highlighted on the tomographic sections and confirmed as perfusion defects by both observe. The present study demonstrated the creation of an atlas of myocardial perfusion scintigraphy with promising results of this tool as an aid in the detection of myocardial perfusion defects. However, further prospective validation with a more representative sample is recommended. (author)

  5. Myocardial delayed-enhancement CT: initial experience in children and young adults

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea, Republic of)

    2017-10-15

    Clinical utility of myocardial delayed enhancement CT has not been reported in children and young adults. To describe initial experience of myocardial delayed enhancement CT regarding image quality, radiation dose and identification of myocardial lesions in children and young adults. Between August 2013 and November 2016, 29 consecutive children and young adults (median age 16 months) with suspected coronary artery or myocardial abnormality underwent arterial- and delayed-phase cardiac CT at our institution. We measured CT densities in normal myocardium, left ventricular cavity, and arterial and delayed hypo-enhancing and delayed hyperenhancing myocardial lesions. We then compared the extent of delayed hyperenhancing lesions with delayed-enhancement MRI or thallium single-photon emission CT. Normal myocardium and left ventricular cavity showed significantly higher CT numbers on arterial-phase CT than on delayed-phase CT (t-test, P<0.0001). Contrast-to-noise ratios of the arterial and delayed hypo-enhancing and delayed hyperenhancing lesions on CT were 26.7, 17.6 and 18.7, respectively. Delayed-phase CT findings were equivalent to those of delayed-enhancement MRI in all cases (7/7) and to those of thallium single-photon emission CT in 70% (7/10). Myocardial delayed-enhancement CT can be added to evaluate myocardial lesions in select children and young adults with suspected coronary artery or myocardial abnormality. (orig.)

  6. Influence of drugs on myocardial iodine-123 metaiodobenzylguanidine uptake in rabbit myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, S.; Karanikas, G.; Rodrigues, M.; Sinzinger, H. [Dept. of Nuclear Medicine, University of Vienna (Austria)

    2000-03-01

    About 15 years ago, iodine-123 metaiodobenzylguanidine (MIBG) myocardial imaging was introduced for the evaluation of myocardial sympathetic nerve function. Two uptake mechanisms for MIBG have so far been identified: uptake type I, a saturable, energy-dependent mechanism, and uptake type II, a non-saturable, energy-independent mechanism. We incubated isolated rabbit myocardial tissue samples with{sup 123}I-MIBG in order to assess the uptake characteristics and the influence of varying incubation conditions. Furthermore, we examined the effects of several drugs and uptake inhibitors on the myocardial uptake of MIBG. The in vitro myocardial uptake of MIBG reached a steady plateau at 23.87%{+-}3.63% after 1 h, i.e. a concentration gradient of 10, in a thermo-independent manner within a concentration range from 1.5 to 1500 {mu}M. This indicates an unsaturable uptake process in the tested concentrations. Pre-incubation with the following drugs caused a significant inhibitory effect on myocardial MIBG uptake: haloperidol, levomepromazine, metoprolol, labetalol and clomipramine. According to our findings, the uptake mechanism seems to be an unspecific process, but the concentration gradient of 10 makes passive diffusion unlikely. Further studies with uptake-II-blocking substances as well as with isolated myocardial cells will be needed to clarify the nature of the myocardial MIBG uptake mechanism. (orig.)

  7. Subdiffraction confinement in dielectric waveguide with extreme anisotropy

    Science.gov (United States)

    Bian, Tingting

    2017-07-01

    All-dielectric slab waveguide filling the core with metamaterials of extreme anisotropy realizes the light transport being confined in a subdiffraction region with substantial energy concentration. The extreme anisotropy makes the evanescent waves in the claddings decay faster and the guided mode tightly localized in the core. Furthermore, the cutoff width can be decoupled from the group velocity of the mode, it can reach zero in the limit of extreme anisotropy but still sustain considerable group velocity. We analyze technically realizable cases and conclude that our work can contribute to improvements of various electromagnetic devices, from visible to microwave frequency regions.

  8. Review of the anisotropy working group at UHECR-2012

    Directory of Open Access Journals (Sweden)

    Ivanov A.

    2013-06-01

    Full Text Available The study of ultra-high energy cosmic rays (UHECRs has recently experienced a jump in statistics as well as improved instrumentation. This has allowed a better sensitivity in searching for anisotropies in the arrival directions of cosmic rays. In this written version of the presentation given by the inter-collaborative “Anisotropy Working Group” at the International Symposium on Future Directions in UHECR physics at CERN in February 2012, we report on the current status for anisotropy searches in the arrival directions of UHECRs.

  9. Canonical Transform Method for Treating Strongly Anisotropy Magnets

    DEFF Research Database (Denmark)

    Cooke, J. F.; Lindgård, Per-Anker

    1977-01-01

    An infinite-order perturbation approach to the theory of magnetism in magnets with strong single-ion anisotropy is given. This approach is based on a canonical transformation of the system into one with a diagonal crystal field, an effective two-ion anisotropy, and reduced ground-state corrections....... A matrix-element matching procedure is used to obtain an explicit expression for the spin-wave energy to second order. The consequences of this theory are illustrated by an application to a simple example with planar anisotropy and an external magnetic field. A detailed comparison between the results...

  10. A mixed domain structure in magnetic films with large anisotropy

    Science.gov (United States)

    Akimov, M. L.; Polyakov, P. A.; Rusakova, N. E.

    2018-01-01

    Influence of anisotropy on a bending of a magnetic stripe domain wall due to a magnetostatic stray field of a cylindrical magnetic domain (CMD) that is located within the stripe one is under investigation. It is revealed that for a specific set of physical parameters of the domain structure, energy of domain wall bending anisotropy can suppress the bending. An analytical expression for the bending shape is obtained on account of a change of both magnetostatic energy of the configuration and energy of anisotropy of the domain wall.

  11. Effects of surface anisotropy on magnetic vortex core

    Energy Technology Data Exchange (ETDEWEB)

    Pylypovskyi, Oleksandr V., E-mail: engraver@univ.net.ua [Taras Shevchenko National University of Kiev, 01601 Kiev (Ukraine); Sheka, Denis D. [Taras Shevchenko National University of Kiev, 01601 Kiev (Ukraine); Kravchuk, Volodymyr P.; Gaididei, Yuri [Institute for Theoretical Physics, 03143 Kiev (Ukraine)

    2014-06-01

    The vortex core shape in the three dimensional Heisenberg magnet is essentially influenced by a surface anisotropy. We predict that depending of the surface anisotropy type there appears barrel- or pillow-shaped deformation of the vortex core along the magnet thickness. Our theoretical study is well confirmed by spin–lattice simulations. - Highlights: • The shape of magnetic vortex core is essentially influenced by SA (surface anisotropy). • We predict barrel- or pillow-shaped deformation of the vortex depending on SA. • The variational approach fully describes the vortex core deformation. • We performed spin–lattice simulations to detect SA influence on the vortex core.

  12. [Changes of myocardial enzymes related to glycolysis and fatty acid metabolism in chronic myocardial ischemia: experiment with pigs].

    Science.gov (United States)

    Gong, Jing; Wang, Hong-yue; Pu, Jie-lin; Zheng, Ying-li; Shen, Rui; Yang, Min-fu; He, Zuo-xiang

    2008-08-12

    To investigate the changes myocardial enzymes related to glycolysis and fatty acid metabolism in chronic myocardial ischemia and to evaluate the relationship between the gene expression of glycolytic metabolism related enzymes and myocardial viability. Fourteen Chinese experimental pigs underwent placement of arterial ring into the left anterior descending coronary artery so as to establish models of myocardial ischemia and infarction. (18)F-2-deoxy-2-fluoro-D-glucose single photon emission computed tomography was conducted to observe the viability of the myocardium. One week later the pigs were killed with their hearts taken out. Specimens of ischemic zone, infarction zone, and non-ischemic zone were obtained. RT-PCR was used to detect the mRNA expression of glucose transporter (GLUT) 1, GLUT4, medium-chain acyl-CoA dehydrogenase (MCAD), and heart-fatty acid binding protein (H-FABP). Immunohistochemistry was used to examine the protein expression of Glut1 and Glut4. Periodic Acid Schiff-hematoxylin staining was conducted to detect the glycogen. Pathological examination showed 5 pigs with myocardial infarction and 5 pigs with ischemia. In the pigs with ischemia, the mRNA expression levels of GLUT1 and GLUT4 in the ischemic zone were 9466 +/- 9033 and 60 398 +/- 64 699 respectively, both significantly higher than those in the control zone (5854 +/- 5287 and 34 188 +/- 44 714 respectively, P = 0.043, P = 0.043). the RNA expression of H-FABP in the ischemic zone was 18 123 +/- 15 925, significantly lower than that in the control zone (50 718 +/- 62 412, P = 0.043), and there was no significant difference in the mRNA expression level of MCAD. In the pigs with infarction the mRNA expression of level of H-FABP in the infarction zone was 21 919 +/- 15 224, significantly lower than that in the control zone (87 545 +/- 92 990, P = 0.043), and there were not significant differences in the mRNA expression levels of the GLUT1, GLUT4, and MCAD genes (all P > 0.05). The m

  13. Evaluation of the diagnostic and prognostic use of gated myocardial perfusion single-photon emission computed tomography in patients with acute chest pain: comparison with the SYNTAX score.

    Science.gov (United States)

    Karacavus, Seyhan; Tutus, Ahmet; Topsakal, Ramazan; Kula, Mustafa; Celik, Ahmet; Abdulrezzak, Ummuhan; Durukan, Polat

    2015-09-01

    The aim of this study was to evaluate the diagnostic and prognostic efficacy of gated single-photon emission computed tomography (GSPECT) in patients with acute chest pain and to compare quantitative GSPECT parameters and the coronary angiographic SYNTAX score. A total of 168 patients who presented with clinical symptoms of acute chest pain were enrolled in the study. Study participants were divided into two groups according to the risk of acute coronary syndrome (ACS): low-intermediate and high risk. All participants underwent rest or stress-GSPECT (R/S-GSPECT). Coronary angiography was performed in all high-risk patients and the SYNTAX score was determined. All patients were followed for 24 ± 3 months and monitored for the occurrence of major adverse coronary events (MACE). Among patients with low-intermediate ACS risk, R-GSPECT and S-GSPECT were associated with 100 and 86% sensitivity, 99 and 98% specificity, 100 and 98% negative predictive value, 80 and 86% positive predictive value, and 98 and 97% accuracy, respectively. At follow-up, MACE occurred in 16 patients. Among high-risk patients, GSPECT quantitative parameters were the most significant predictors of MACE in Cox regression analysis. R/S-GSPECT, a noninvasive diagnostic method, is associated with an excellent safety profile and exceptional diagnostic and prognostic accuracy in cases of ACS.

  14. Protocol for an economic evaluation of the randomised controlled trial of culprit lesion only PCI versus immediate multivessel PCI in acute myocardial infarction complicated by cardiogenic shock: CULPRIT-SHOCK trial.

    Science.gov (United States)

    Quayyum, Zahidul; Briggs, Andrew; Robles-Zurita, Jose; Oldroyd, Keith; Zeymer, Uwe; Desch, Steffen; Waha, Suzanne de; Thiele, Holger

    2017-08-18

    Emergency percutaneous coronary intervention (PCI) of the culprit lesion for patients with acute myocardial infarctions is an accepted practice. A majority of patients present with multivessel disease with additional relevant stenoses apart from the culprit lesion. In haemodynamically stable patients, there is increasing evidence from randomised trials to support the practice of immediate complete revascularisation. However, in the presence of cardiogenic shock, the optimal management strategy for additional non-culprit lesions is unknown. A multicentre randomised controlled trial, CULPRIT-SHOCK, is examining whether culprit vessel only PCI with potentially subsequent staged revascularisation is more effective than immediate multivessel PCI. This paper describes the intended economic evaluation of the trial. The economic evaluation will be conducted using a pre-trial decision model and within-trial analysis. The modelling-based analysis will provide expected costs and health outcomes, and incremental cost-effectiveness ratio over the lifetime for the cohort of patients included in the trial. The within-trial analysis will provide estimates of cost per life saved at 30 days and in 1 year, and estimates of health-related quality of life. Bootstrapping and cost-effectiveness acceptability curves will be used to address any uncertainty around these estimates. Different types of regression models within a generalised estimating equation framework will be used to examine how the total cost and quality-adjusted life years are explained by patients' characteristics, revascularisation strategy, country and centre. The cost-effectiveness analysis will be from the perspective of each country's national health services, where costs will be expressed in euros adjusted for purchasing power parity. Ethical approval for the study was granted by the local Ethics Committee at each recruiting centre. The economic evaluation analyses will be published in peer-reviewed journals of

  15. Myocardial perfusion alterations observed months after radiotherapy are related to the cellular damage

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, I.; Sonmez, B. [Karadeniz Technical Univ., Trabzon (Turkey). Dept. of Nuclear Medicine; Sezen, O.; Zengin, A.Y.; Bahat, Z. [Karadeniz Technical Univ., Trabzon (Turkey). Dept. of Radiation Oncology; Yenilmez, E.; Yulug, E. [Karadeniz Technical Univ., Trabzon (Turkey). Dept. of Histology and Embryology; Abidin, I. [Karadeniz Technical Univ., Trabzon (Turkey). Dept. of Biophysics

    2010-07-01

    Myocardial perfusion scintigraphy (MPS) is one of the widely used tools to follow developing radiation-induced heart disease (RIHD). But the clinical significance of MPS defects has not been fully understood. We have investigated the biodistribution alterations related to perfusion defects following radiotherapy (RT) and showed coexisting morphological changes. Animals, methods: A total of 18 Wistar rats were divided into three groups (1 control and 2 irradiated groups). A single cardiac 20 Gy radiation dose was used to induce long term cardiac defects. Biodistribution studies with technetium ({sup 99m}Tc) sestamibi and histological evaluations were performed 4 and 6 months after irradiation. The percent radioactivity (%ID/g) was calculated for each heart. For determination of the myocardial damage, positive apoptotic cardiomyocytes, myocardial cell degeneration, myocardial fibrosis, vascular damage and ultrastructural structures were evaluated. Results: Six months after treatment, a significant drop of myocardial uptake was observed (p < 0.05). Irradiation-induced apoptosis rose within the first 4 months after radiation treatment and were stayed elevated until the end of the observation period (p < 0.05). Also, the irradiation has induced myocardial degeneration, perivascular and interstitial fibrosis in the heart at the end of six and four months (p < 0.01). The severity and extent of myocardial injury has became more evident at the end of six month (p < 0.05). At ultrastructural level, prominent changes have been observed in the capillary endothelial and myocardial cells. Conclusion: Our findings suggest that the reduced rest myocardial perfusion, occuring months after the radiation, indicates a serious myocard tissue damage which is characterized by myocardial degeneration and fibrosis. (orig.)

  16. Functional evaluation of human donation after cardiac death donor hearts using a continuous isolated myocardial perfusion technique: Potential for expansion of the cardiac donor population.

    Science.gov (United States)

    Osaki, Satoru; Locher, Matthew R; Lushaj, Entela B; Akhter, Shahab A; Kohmoto, Takushi

    2014-09-01

    To investigate the resuscitation potential and contractile function in adult human donation after cardiac death (DCD) hearts by ex vivo perfusion. With institutional review board approval and under the DCD protocol at the University of Wisconsin (UW) Organ Procurement Organization, 5 brain dead (BD) and 5 DCD donor hearts were evaluated. All BD hearts were declined for clinical transplantation because of coronary artery disease, advanced age, or social history. All hearts were preserved by flushing and cold storage with UW solution. By using our ex vivo perfusion system, the left ventricular end systolic pressure-volume relationship (LV-ESPVR) was assessed for 2 hours of oxygenated blood reperfusion. All BD (n = 5) and 4 DCD hearts were successfully resuscitated. One DCD heart was unable to be resuscitated due to prolonged warm ischemic time (WIT; 174 minutes). Mean WIT for resuscitated DCD hearts (from extubation to flushing with cold UW solution) was 34 ± 3 minutes (range, 26 to 40 minutes); mean cold ischemic time for BD donors was 211 ± 31 minutes compared with 177 ± 64 minutes for DCD donors. The calculated LV-ESPVRs for BD hearts after 1 and 2 hours of reperfusion were 6.9 ± 0.7 and 5.7 ± 1.0 mm Hg/mL, respectively; LV-ESPVRs for DCD hearts after 1 and 2 hours of reperfusion were 5.6 ± 1.5 (P = .45) and 3.0 ± 0.7 mm Hg/mL (P = .07), respectively. We successfully resuscitated and measured ex vivo cardiac function in human DCD and BD donor hearts. Resuscitation potential in DCD hearts was achieved when the WIT was less than 40 minutes. Contractile performance in DCD hearts tended to be lower compared with BD hearts. Further investigation with longer reperfusion periods seems warranted. Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  17. Heart-type Fatty acid-binding protein in Acute Myocardial infarction Evaluation (FAME: Background and design of a diagnostic study in primary care

    Directory of Open Access Journals (Sweden)

    Doevendans Pieter A

    2008-04-01

    Full Text Available Abstract Background Currently used biomarkers for cardiac ischemia are elevated in blood plasma after a delay of several hours and therefore unable to detect acute coronary syndrome (ACS in a very early stage. General practitioners (GPs, however, are often confronted with patients suspected of ACS within hours after onset of complaints. This ongoing study aims to evaluate the added diagnostic value beyond clinical assessment for a rapid bedside test for heart-type fatty-acid binding protein (H-FABP, a biomarker that is detectable as soon as one hour after onset of ischemia. Methods Participating GPs perform a blinded H-FABP rapid bedside test (Cardiodetect® in patients with symptoms suggestive of ACS such as chest pain or discomfort at rest. All patients, whether referred to hospital or not, undergo electrocardiography (ECG and venapunction for a plasma troponin test within 12–36 hours after onset of complaints. A final diagnosis will be established by an expert panel consisting of two cardiologists and one general practitioner (blinded to the H-FABP test result, using all available patient information, also including signs and symptoms. The added diagnostic value of the H-FABP test beyond history taking and physical examination will be determined with receiver operating characteristic curves derived from multivariate regression analysis. Conclusion Reasons for presenting the design of our study include the prevention of publication bias and unacknowledged alterations in the study aim, design or data-analysis. To our knowledge this study is the first to assess the diagnostic value of H-FABP outside a hospital-setting. Several previous hospital-based studies showed the potential value of H-FABP in diagnosing ACS. Up to now however it is unclear whether these results are equally promising when the test is used in primary care. The first results are expected in the end of 2008.

  18. Effect of loading-dose ticagrelor on coronary blood flow, left ventricular remodeling and myocardial enzyme spectrum in patients with acute myocardial infarction after interventional therapy

    Directory of Open Access Journals (Sweden)

    Xiao-Rui Xie

    2016-12-01

    Full Text Available Objective: To study the effect of loading-dose ticagrelor on coronary blood flow, left ventricular remodeling and myocardial enzyme spectrum in patients with acute myocardial infarction after interventional therapy. Methods: A total of 86 patients with acute myocardial infarction who received emergency PCI in our hospital between May 2013 and May 2016 were selected and randomly divided into two groups, ticagrelor group received perioperative ticagrelor therapy and clopidogrel group received perioperative clopidogrel therapy. After PCI, coronary blood flow reperfusion was evaluated, serum myocardial remodeling indexes and myocardial enzymes were determined, and cardiac color Doppler ultrasonography was conducted to determine the cardiac function indexes. Results: TIMI grading and TMPG grading of ticagrelor group after PCI were significantly higher than those of clopidogrel group; serum MMP9, BNP, CITP, PICP, PIIINP, CK, CK-MB, cTnI and cTnT content of ticagrelor group 24h after operation were significantly lower than those of clopidogrel group; LVEDD, LVSED and LVMI of ticagrelor group 2 weeks after operation were significantly lower than those of clopidogrel group while LVEF was significantly higher than that of clopidogrel group. Conclusion: Peri-PCI loading-dose ticagrelor can improve coronary blood perfusion and reduce ventricular remodeling and myocardial injury in patients with acute myocardial infarction.

  19. Relationship between electrical conductivity anisotropy and fabric anisotropy in granular materials during drained triaxial compressive tests: a numerical approach

    Science.gov (United States)

    Niu, Qifei; Revil, André; Li, Zhaofeng; Wang, Yu-Hsing

    2017-07-01

    The anisotropy of granular media and its evolution during shearing are important aspects required in developing physics-based constitutive models in Earth sciences. The development of relationships between geoelectrical properties and the deformation of porous media has applications to the monitoring of faulting and landslides. However, such relationships are still poorly understood. In this study, we first investigate the definition of the electrical conductivity anisotropy tensor of granular materials in presence of surface conductivity of the grains. Fabric anisotropy is related to the components of the fabric tensor. We define an electrical anisotropy factor based on the Archie's exponent second-order symmetric tensor m of granular materials. We use numerical simulations to confirm a relationship between the evolution of electrical and fabric anisotropy factors during shearing. To realize the simulations, we build a virtual laboratory in which we can easily perform synthetic experiments. We first simulate drained compressive triaxial tests of loose and dense granular materials (porosity 0.45 and 0.38, respectively) using the discrete element method. Then, the electrical conductivity tensor of a set of deformed synthetic samples is computed using the finite-difference method. The numerical results show that shear strains are responsible for a measurable anisotropy in the bulk conductivity of granular media. The observed electrical anisotropy response, during shearing, is distinct for dense and loose synthetic samples. Electrical and fabric anisotropy factors exhibit however a unique linear correlation, regardless of the shear strain and the initial state (porosity) of the synthetic samples. The practical implication of this finding confirms the usefulness of the electrical conductivity method in studying the fabric tensor of granular media. This result opens the door in using time-lapse electrical resistivity to study non-intrusively the evolution of anisotropy

  20. Anisotropy of the magnetic susceptibility of gallium

    Science.gov (United States)

    Pankey, T.

    1960-01-01

    The bulk magnetic susceptibilities of single gallium crystals and polycrystalline gallium spheres were measured at 25??C. The following anisotropic diamagnetic susceptibilities were found: a axis (-0.119??0. 001)??10-6 emu/g, b axis (-0.416??0.002)??10 -6 emu/g, and c axis (-0.229??0.001) emu/g. The susceptibility of the polycrystalline spheres, assumed to be the average value for the bulk susceptibility of gallium, was (-0.257??0.003)??10-6 emu/g at 25??C, and (-0.299??0.003)??10-6 emu/g at -196??C. The susceptibility of liquid gallium was (0.0031??0.001) ??10-6 emu/g at 30??C and 100??C. Rotational diagrams of the susceptibilities in the three orthogonal planes of the unit cell were not sinusoidal. The anisotropy in the single crystals was presumably caused by the partial overlap of Brillouin zone boundaries by the Fermi-energy surface. The large change in susceptibility associated with the change in state was attributed to the absence of effective mass influence in the liquid state. ?? 1960 The American Institute of Physics.

  1. Patchy polymer colloids with tunable anisotropy dimensions.

    Science.gov (United States)

    Kraft, Daniela J; Hilhorst, Jan; Heinen, Maria A P; Hoogenraad, Mathijs J; Luigjes, Bob; Kegel, Willem K

    2011-06-09

    We present the synthesis of polymer colloids with continuously tunable anisotropy dimensions: patchiness, roughness, and branching. Our method makes use of controlled fusion of multiple protrusions on highly cross-linked polymer particles produced by seeded emulsion polymerization. Carefully changing the synthesis conditions, we can tune the number of protrusions, or branching, of the obtained particles from spheres with one to three patches to raspberry-like particles with multiple protrusions. In addition to that, roughness is generated on the seed particles by adsorption of secondary nucleated particles during synthesis. The size of the roughness relative to the smooth patches can be continuously tuned by the initiator, surfactant, and styrene concentrations. Seed colloids chemically different from the protrusions induce patches of different chemical nature. The underlying generality of the synthesis procedure allows for application to a variety of seed particle sizes and materials. We demonstrate the use of differently sized polyNIPAM (poly-N-isopropylacrylamide), as well as polystyrene and magnetite filled polyNIPAM seed particles, the latter giving rise to magnetically anisotropic colloids. The high yield together with the uniform, anisotropic shape make them interesting candidates for use as smart building blocks in self-assembling systems.

  2. High anisotropy of fully hydrogenated borophene

    Science.gov (United States)

    Wang, Zhiqiang; Lü, Tie-Yu; Wang, Hui-Qiong; Feng, Yuan Ping; Zheng, Jin-Cheng

    We have studied the mechanical properties and phonon dispersions of fully hydrogenated borophene (borophane) under strains by first principles calculations. Uniaxial tensile strains along the a- and b-direction, respectively, and biaxial tensile strain have been considered. Our results show that the mechanical properties and phonon stability of borophane are both highly anisotropic. The ultimate tensile strain along the a-direction is only 0.12, but it can be as large as 0.30 along the b-direction. Compared to borophene and other 2D materials (graphene, graphane, silicene, silicane, h-BN, phosphorene and MoS2), borophane presents the most remarkable anisotropy in in-plane ultimate strain, which is very important for strain engineering. Furthermore, the phonon dispersions under the three applied strains indicate that borophane can withstand up to 5% and 15% uniaxial tensile strain along the a- and b-direction, respectively, and 9% biaxial tensile strain, indicating that mechanical failure in borophane is likely to originate from phonon instability.

  3. Studies of anisotropy of iron based superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, Jason A. [Iowa State Univ., Ames, IA (United States)

    2013-01-01

    To study the electronic anisotropy in iron based superconductors, the temperature dependent London penetration depth, Δλ(T), have been measured in several compounds, along with the angular dependent upper critical field, Hc2(T). Study was undertaken on single crystals of Ba(Fe1-xCox)2As2 with x=0.108 and x=0.127, in the overdoped range of the doping phase diagram, characterized by notable modulation of the superconducting gap. Heavy ion irradiation with matching field doses of 6 T and 6.5 T respectively, were used to create columnar defects and to study their effect on the temperature Δλ(T). The variation of the low-temperature penetration depth in both pristine and irradiated samples was fitted with a power-law function Δλ(T) = ATn. Irradiation increases the magnitude of the pre-factor A and decreases the exponent n, similar to the effect on the optimally doped samples. This finding supports the universal s ± scenario for the whole doping range.

  4. Nanoscale magnetic ratchets based on shape anisotropy

    Science.gov (United States)

    Cui, Jizhai; Keller, Scott M.; Liang, Cheng-Yen; Carman, Gregory P.; Lynch, Christopher S.

    2017-02-01

    Controlling magnetization using piezoelectric strain through the magnetoelectric effect offers several orders of magnitude reduction in energy consumption for spintronic applications. However strain is a uniaxial effect and, unlike directional magnetic field or spin-polarized current, cannot induce a full 180° reorientation of the magnetization vector when acting alone. We have engineered novel ‘peanut’ and ‘cat-eye’ shaped nanomagnets on piezoelectric substrates that undergo repeated deterministic 180° magnetization rotations in response to individual electric-field-induced strain pulses by breaking the uniaxial symmetry using shape anisotropy. This behavior can be likened to a magnetic ratchet, advancing magnetization clockwise with each piezostrain trigger. The results were validated using micromagnetics implemented in a multiphysics finite elements code to simulate the engineered spatial and temporal magnetic behavior. The engineering principles start from a target device function and proceed to the identification of shapes that produce the desired function. This approach opens a broad design space for next generation magnetoelectric spintronic devices.

  5. Patient satisfaction with coronary CT angiography, myocardial CT perfusion, myocardial perfusion MRI, SPECT myocardial perfusion imaging and conventional coronary angiography

    Energy Technology Data Exchange (ETDEWEB)

    Feger, S.; Rief, M.; Zimmermann, E.; Richter, F.; Roehle, R. [Freie Universitaet Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin Campus Mitte, Humboldt-Universitaet zu Berlin, Berlin (Germany); Dewey, M. [Freie Universitaet Berlin, Department of Radiology, Charite - Universitaetsmedizin Berlin Campus Mitte, Humboldt-Universitaet zu Berlin, Berlin (Germany); Institut fuer Radiologie, Berlin (Germany); Schoenenberger, E. [Medizinische Hochschule Hannover, Department of Medicine, Hannover (Germany)

    2015-07-15

    To evaluate patient acceptance of noninvasive imaging tests for detection of coronary artery disease (CAD), including single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI), stress perfusion magnetic resonance imaging (MRI), coronary CT angiography (CTA) in combination with CT myocardial stress perfusion (CTP), and conventional coronary angiography (CCA). Intraindividual comparison of perception of 48 patients from the CORE320 multicentre multinational study who underwent rest and stress SPECT-MPI with a technetium-based tracer, combined CTA and CTP (both with contrast agent, CTP with adenosine), MRI, and CCA. The analysis was performed by using a validated questionnaire. Patients had significantly more concern prior to CCA than before CTA/CTP (p < 0.001). CTA/CTP was also rated as more comfortable than SPECT-MPI (p = 0.001). Overall satisfaction with CT was superior to that of MRI (p = 0.007). More patients preferred CT (46 %; p < 0.001) as a future diagnostic test. Regarding combined CTA/CTP, CTP was characterised by higher pain levels and an increased frequency of angina pectoris during the examination (p < 0.001). Subgroup analysis showed a higher degree of pain during SPECT-MPI with adenosine stress compared to physical exercise (p = 0.016). All noninvasive cardiac imaging tests are well accepted by patients, with CT being the preferred examination. (orig.)

  6. Influence of isoproterenol on myocardial energetics. Experimental and clinical investigations.

    Science.gov (United States)

    Hasenfuss, G; Holubarsch, C; Blanchard, E M; Mulieri, L A; Alpert, N R; Just, H

    1989-01-01

    The influence of isoproterenol on myocardial performance and energetics was investigated in normal guinea pig myocardium and in patients with normal left ventricular function. The in vitro experiments were performed by simultaneous isometric force and heat measurements using sensitive antimony-bismuth thermopiles. Following the application of isoproterenol (10(-8) M) isometric peak twitch tension and tension-time integral increased significantly by 185% and 142%, respectively. Tension-independent heat which reflects high energy phosphate hydrolysis of excitation-contraction coupling increased by 183%. Tension-dependent heat reflecting the high energy phosphate hydrolysis of the crossbridges increased by 417%. The ratio of tension-dependent heat to tension-time integral increased by 131%. The recovery/initial heat ratio, reflecting the efficiency of the recovery metabolism, and the resting metabolism did not significantly change. In the patients the effect of isoproterenol on myocardial energetics was evaluated in terms of myocardial efficiency. Following isoproterenol administration, left ventricular systolic stress-time integral decreased by 49% due to reductions in end-diastolic pressure, end-diastolic volume and duration of systole. Pressure-volume work remained unchanged. Myocardial oxygen consumption per minute increased in proportion to heart rate. The ratio of myocardial oxygen consumption per beat to left ventricular systolic stress-time integral increased significantly by 95%. External myocardial efficiency was unaltered. Thus, isoproterenol increases the energy turnover of excitation-contraction coupling and increases the energy consumption of the crossbridges disproportionately to developed tension-time integral in the guinea pig heart.

  7. Dense motion field estimation from myocardial boundary displacements.

    Science.gov (United States)

    Morais, Pedro; Queirós, Sandro; Ferreira, Adriano; Rodrigues, Nuno F; Baptista, Maria J; D'hooge, Jan; Vilaça, João L; Barbosa, Daniel

    2016-09-01

    Minimally invasive cardiovascular interventions guided by multiple imaging modalities are rapidly gaining clinical acceptance for the treatment of several cardiovascular diseases. These images are typically fused with richly detailed pre-operative scans through registration techniques, enhancing the intra-operative clinical data and easing the image-guided procedures. Nonetheless, rigid models have been used to align the different modalities, not taking into account the anatomical variations of the cardiac muscle throughout the cardiac cycle. In the current study, we present a novel strategy to compensate the beat-to-beat physiological adaptation of the myocardium. Hereto, we intend to prove that a complete myocardial motion field can be quickly recovered from the displacement field at the myocardial boundaries, therefore being an efficient strategy to locally deform the cardiac muscle. We address this hypothesis by comparing three different strategies to recover a dense myocardial motion field from a sparse one, namely, a diffusion-based approach, thin-plate splines, and multiquadric radial basis functions. Two experimental setups were used to validate the proposed strategy. First, an in silico validation was carried out on synthetic motion fields obtained from two realistic simulated ultrasound sequences. Then, 45 mid-ventricular 2D sequences of cine magnetic resonance imaging were processed to further evaluate the different approaches. The results showed that accurate boundary tracking combined with dense myocardial recovery via interpolation/diffusion is a potentially viable solution to speed up dense myocardial motion field estimation and, consequently, to deform/compensate the myocardial wall throughout the cardiac cycle. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  8. Facilitation of primary coronary angioplasty by early start of a glycoprotein 2b/3a inhibitor: results of the ongoing tirofiban in myocardial infarction evaluation (On-TIME) trial

    NARCIS (Netherlands)

    van 't Hof, Arnoud W. J.; Ernst, Nicolette; de Boer, Menko-Jan; de Winter, Rob; Boersma, Eric; Bunt, Ton; Petronio, Sonia; Marcel Gosselink, A. T.; Jap, Walter; Hollak, Frans; Hoorntje, Jan C. A.; Suryapranata, Harry; Dambrink, Jan-Henk E.; Zijlstra, Felix

    2004-01-01

    Although primary angioplasty is effective despite additional transportation delay, improved patency before PCI might be obtained by starting pharmacological pre-treatment before transportation. From June 2001 to November 2002, 507 patients with acute myocardial infarction, who were transferred to a

  9. Shape Accuracy of Iron Precision Castings in Terms of Ceramic Moulds Physical Properties Anisotropy

    Directory of Open Access Journals (Sweden)

    Biernacki R.

    2014-03-01

    Full Text Available While analyzing shape accuracy of ferroalloy precision castings in terms of ceramic moulds physical anisotropy, low-alloy steel castings ("cover" and cast iron ("plate" were included. The basic parameters in addition to the product linear shape accuracy are flatness deviations, especially due to the expanded flat surface which is cast plate. For mentioned castings surface micro-geometry analysis was also carried, favoring surface load capacity tp50 for Rmax = 50%. Surface load capacity tp50 obtained for the cast cover was compared with machined product, and casting plate surface was compared with wear part of the conveyor belt. The results were referred to anisotropy of ceramic moulds physical properties, which was evaluated by studying ceramic moulds samples in computer tomography equipment Metrotom 800

  10. CoTaZr/Pd multilayer with perpendicular magnetic anisotropy

    Directory of Open Access Journals (Sweden)

    Yong Chang Lau

    2013-08-01

    Full Text Available We report a novel perpendicularly magnetized thin film [Co91.5Ta4.5Zr4/Pd]5 multilayer, which exhibits strong perpendicular magnetic anisotropy when grown on 5 nm of Pd and Ru seed layers. The Pd-seeded multilayer annealed at 300 °C shows an effective uniaxial anisotropy constant, Keff = 1.1 MJ m−3, with an anisotropy field as high as 1.6 T. The perpendicular anisotropy is sustained on annealing at 400 °C for 1 h. X-ray diffraction on multilayers with 30 repeats suggests that the use of amorphous CoTaZr reduces the stress of the stack, compared to [Co/Pd] multilayer.

  11. Thermoelectric anisotropy and texture of intercalated TiS2

    Science.gov (United States)

    Guilmeau, E.; Barbier, T.; Maignan, A.; Chateigner, D.

    2017-09-01

    This study addresses the effect of anisotropy on the electrical and thermal properties of CuxTiS2 compounds. We show that the anisotropy of the electrical resistivity (ρcross-plane/ρin-plane > 1) tends to be reduced as the covalent character along c is increased with the Cu content. For all x values (x ≤ 0.1), the absolute value of S is always found to be higher in-plane than in the cross-plane direction due to band structure anisotropy, leading to higher in-plane power factor values. Interestingly, the κin-plane/κcross-plane thermal conductivity ratio, with values similar to the only data reported for TiS2 crystals, are always higher than ρcross-plane/ρin-plane. This anisotropy relation leads to equivalent zT values for the in-plane and cross-plane directions, reaching 0.35-0.5 at 800 K.

  12. Friction Anisotropy: A unique and intrinsic property of decagonal quasicrystals

    Energy Technology Data Exchange (ETDEWEB)

    Mulleregan, Alice; Park, Jeong Young; Salmeron, Miquel; Ogetree, D.F.; Jenks, C.J.; Thiel, P.A.; Brenner, J.; Dubois, J.M.

    2008-06-25

    We show that friction anisotropy is an intrinsic property of the atomic structure of Al-Ni-Co decagonal quasicrystals and not only of clean and well-ordered surfaces that can be prepared in vacuum [J.Y. Park et al., Science (2005)]. Friction anisotropy is manifested both in nanometer size contacts obtained with sharp atomic force microscope (AFM) tips as well as in macroscopic contacts produced in pin-on-disc tribometers. We show that the friction anisotropy, which is not observed when an amorphous oxide film covers the surface, is recovered when the film is removed due to wear. Equally important is the loss of the friction anisotropy when the quasicrystalline order is destroyed due to cumulative wear. These results reveal the intimate connection between the mechanical properties of these materials and their peculiar atomic structure.

  13. Model C critical dynamics of random anisotropy magnets

    Energy Technology Data Exchange (ETDEWEB)

    Dudka, M [Institute for Condensed Matter Physics, National Acad. Sci. of Ukraine, UA-79011 Lviv (Ukraine); Folk, R [Institut fuer Theoretische Physik, Johannes Kepler Universitaet Linz, A-4040 Linz (Austria); Holovatch, Yu [Institute for Condensed Matter Physics, National Acad. Sci. of Ukraine, UA-79011 Lviv (Ukraine); Moser, G [Institut fuer Physik und Biophysik, Universitaet Salzburg, A-5020 Salzburg (Austria)

    2007-07-20

    We study the relaxational critical dynamics of the three-dimensional random anisotropy magnets with the non-conserved n-component order parameter coupled to a conserved scalar density. In the random anisotropy magnets, the structural disorder is present in the form of local quenched anisotropy axes of random orientation. When the anisotropy axes are randomly distributed along the edges of the n-dimensional hypercube, asymptotical dynamical critical properties coincide with those of the random-site Ising model. However the structural disorder gives rise to considerable effects for non-asymptotic critical dynamics. We investigate this phenomenon by a field-theoretical renormalization group analysis in the two-loop order. We study critical slowing down and obtain quantitative estimates for the effective and asymptotic critical exponents of the order parameter and scalar density. The results predict complex scenarios for the effective critical exponent approaching the asymptotic regime.

  14. Anisotropies of in-phase, out-of-phase,\

    Czech Academy of Sciences Publication Activity Database

    Hrouda, F.; Chadima, Martin; Ježek, J.; Kadlec, Jaroslav

    2018-01-01

    Roč. 62 (2018) ISSN 0039-3169 Institutional support: RVO:67985530 ; RVO:67985831 Keywords : anisotropy * out-of-phase susceptibility * frequency-dependent susceptibility Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.764, year: 2016

  15. Dark matter electron anisotropy. A universal upper limit

    Energy Technology Data Exchange (ETDEWEB)

    Borriello, Enrico [Universita ' ' Federico II' ' , Napoli (Italy). Dipt. di Scienze Fisiche; INFN, Sezione di Napoli (Italy); Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Maccione, Luca [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Cuoco, Alessandro [Oskar Klein Centre for Cosmoparticle Physics, Stockholm (Sweden)

    2010-12-15

    Indirect searches of particle Dark Matter (DM) with high energy Cosmic Rays (CR) are affected by large uncertainties, coming both from the DM side, and from poor understanding of the astrophysical backgrounds. We show that, on the contrary, the DM intrinsic degree of anisotropy in the arrival directions of high energy CR electrons and positrons does not suffer from these unknowns. Furthermore, if contributions from possible local sources are neglected, the intrinsic DM anisotropy sets the maximum degree of total anisotropy. As a consequence, if some anisotropy larger than the DM upper bound is detected, its origin could not be ascribed to DM, and would constitute an unambiguous evidence for the presence of astrophysical local discrete sources of high energy electrons and positrons. The Fermi-LAT will be able to probe such scenarios in the next years. (orig.)

  16. Perceived stress in myocardial infarction

    NARCIS (Netherlands)

    Arnold, Suzanne V.; Smolderen, K.G.E.; Buchanan, Donna M.; Li, Yan; Spertus, John A.

    2012-01-01

    Objectives This study sought to determine the association of chronic stress with long-term adverse outcomes after acute myocardial infarction (AMI).BackgroundChronic stress has been shown to be associated with the development of cardiovascular disease and, in the case of particular types of stress

  17. Neonatal Myocardial Infarction or Myocarditis?

    NARCIS (Netherlands)

    de Vetten, Leanne; Bergman, Klasien A.; Elzenga, Nynke J.; van Melle, Joost P.; Timmer, Albertus; Bartelds, Beatrijs

    We report a 29 week-gestation preterm infant who presented during his second week of life with cardiogenic shock. Clinical presentation and first diagnostics suggested myocardial infarction, but echocardiographic features during follow-up pointed to a diagnosis of enteroviral myocarditis. The child

  18. Myocardial perfusion at fatal infarction

    DEFF Research Database (Denmark)

    Hvid-Jacobsen, K; Møller, J T; Kjøller, E

    1992-01-01

    In a consecutive study of myocardial scintigraphy in acute ischemic syndrome, four patients had 99mTc-hexamibi injected intravenously before they developed fatal cardiogenic shock. Planar scintigraphy was performed after death. Slices of the hearts after autopsy were analyzed for scintigraphic...

  19. Regional myocardial perfusion and performance

    NARCIS (Netherlands)

    H.C. Schamhardt (Henk)

    1980-01-01

    textabstractThe function of the heart is to pump blood from the veins into the arteries in response to the need of the tissues for oxygen and substrates. During its action the heart itself needs these nutrients. Factors that mainly determine the myocardial oxygen demand are (fig.0.1): heart rate,

  20. The Orchestra of Myocardial Regeneration

    NARCIS (Netherlands)

    Siddiqi, S.

    2014-01-01

    A glimpse on previous and current literature ignites the recognition of the luxurious era that cardiac science has reached. In particular, the past fifteen years have provided tremendous advancements in the field of myocardial biology with the characterization of cardiac stem cells, reprogramming of

  1. Pregnancy-related myocardial infarction

    NARCIS (Netherlands)

    Lameijer, H.; Lont, M. C.; Buter, H.; van Boven, A. J.; Boonstra, P. W.; Pieper, P. G.

    Introduction The risk of acute myocardial infarction in young women is low, but increases during pregnancy due to the physiological changes in pregnancy, including hypercoagulability. Ischaemic heart disease during pregnancy is not only associated with increased maternal morbidity and mortality, but

  2. Spousal Adjustment to Myocardial Infarction.

    Science.gov (United States)

    Ziglar, Elisa J.

    This paper reviews the literature on the stresses and coping strategies of spouses of patients with myocardial infarction (MI). It attempts to identify specific problem areas of adjustment for the spouse and to explore the effects of spousal adjustment on patient recovery. Chapter one provides an overview of the importance in examining the…

  3. Quantifying seismic anisotropy induced by small-scale chemical heterogeneities

    Science.gov (United States)

    Alder, C.; Bodin, T.; Ricard, Y.; Capdeville, Y.; Debayle, E.; Montagner, J. P.

    2017-12-01

    Observations of seismic anisotropy are usually used as a proxy for lattice-preferred orientation (LPO) of anisotropic minerals in the Earth's mantle. In this way, seismic anisotropy observed in tomographic models provides important constraints on the geometry of mantle deformation associated with thermal convection and plate tectonics. However, in addition to LPO, small-scale heterogeneities that cannot be resolved by long-period seismic waves may also produce anisotropy. The observed (i.e. apparent) anisotropy is then a combination of an intrinsic and an extrinsic component. Assuming the Earth's mantle exhibits petrological inhomogeneities at all scales, tomographic models built from long-period seismic waves may thus display extrinsic anisotropy. In this paper, we investigate the relation between the amplitude of seismic heterogeneities and the level of induced S-wave radial anisotropy as seen by long-period seismic waves. We generate some simple 1-D and 2-D isotropic models that exhibit a power spectrum of heterogeneities as what is expected for the Earth's mantle, that is, varying as 1/k, with k the wavenumber of these heterogeneities. The 1-D toy models correspond to simple layered media. In the 2-D case, our models depict marble-cake patterns in which an anomaly in shear wave velocity has been advected within convective cells. The long-wavelength equivalents of these models are computed using upscaling relations that link properties of a rapidly varying elastic medium to properties of the effective, that is, apparent, medium as seen by long-period waves. The resulting homogenized media exhibit extrinsic anisotropy and represent what would be observed in tomography. In the 1-D case, we analytically show that the level of anisotropy increases with the square of the amplitude of heterogeneities. This relation is numerically verified for both 1-D and 2-D media. In addition, we predict that 10 per cent of chemical heterogeneities in 2-D marble-cake models can

  4. Biomarkers in acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    Ng Leong L

    2010-06-01

    Full Text Available Abstract Myocardial infarction causes significant mortality and morbidity. Timely diagnosis allows clinicians to risk stratify their patients and select appropriate treatment. Biomarkers have been used to assist with timely diagnosis, while an increasing number of novel markers have been identified to predict outcome following an acute myocardial infarction or acute coronary syndrome. This may facilitate tailoring of appropriate therapy to high-risk patients. This review focuses on a variety of promising biomarkers which provide diagnostic and prognostic information. Heart-type Fatty Acid Binding Protein and copeptin in combination with cardiac troponin help diagnose myocardial infarction or acute coronary syndrome in the early hours following symptoms. An elevated N-Terminal Pro-B-type Natriuretic Peptide has been well validated to predict death and heart failure following a myocardial infarction. Similarly other biomarkers such as Mid-regional pro-Atrial Natriuretic Peptide, ST2, C-Terminal pro-endothelin 1, Mid-regional pro-Adrenomedullin and copeptin all provide incremental information in predicting death and heart failure. Growth differentiation factor-15 and high-sensitivity C-reactive protein predict death following an acute coronary syndrome. Pregnancy associated plasma protein A levels following chest pain predicts risk of myocardial infarction and revascularisation. Some biomarkers such as myeloperoxidase and high-sensitivity C-reactive protein in an apparently healthy population predicts risk of coronary disease and allows clinicians to initiate early preventative treatment. In addition to biomarkers, various well-validated scoring systems based on clinical characteristics are available to help clinicians predict mortality risk, such as the Thrombolysis In Myocardial Infarction score and Global Registry of Acute Coronary Events score. A multimarker approach incorporating biomarkers and clinical scores will increase the prognostic

  5. Mortality rate in type 2 myocardial infarction

    DEFF Research Database (Denmark)

    Saaby, Lotte; Poulsen, Tina Svenstrup; Diederichsen, Axel Cosmus Pyndt

    2014-01-01

    2 myocardial infarction. CONCLUSIONS: Mortality in patients with type 2 myocardial infarction is high, reaching approximately 50% after 2 years. Further descriptive and survival studies are needed to improve the scientific evidence on which treatment of type 2 myocardial infarction is based.......BACKGROUND: The classification of myocardial infarction into 5 types was introduced in 2007. The prognostic impact of this universal definition, with particular focus on type 2 myocardial infarction, has not been studied prospectively in unselected hospital patients. METHODS: During a 1-year period......, all hospitalized patients having cardiac troponin I measured were considered. The diagnosis of a myocardial infarction was according to the universal definition, and specified criteria were used in the classification of type 2 myocardial infarction. Follow-up was at least 1 year, with mortality...

  6. Polarimetric investigation of materials with both linear and circular anisotropy

    DEFF Research Database (Denmark)

    Naydenova, I.; Nikolova, L.; Todorov, T.

    1997-01-01

    We investigate light propagation through materials with both linear and circular anisotropy and find the relation of the amplitude and polarization transfer functions to the four anisotropic characteristics: linear circular birefringence, and linear and circular dichroism. We determine these four...... characteristics of anisotropic samples by measuring the output intensity and polarization corresponding to different input polarization azimuths and fitting the theoretical and experimental results. In our experiments we have used films of side-chain azobenzene polyesters in which optical anisotropy had been...

  7. Electronic, magnetic, and magnetocrystalline anisotropy properties of light lanthanides

    Science.gov (United States)

    Hackett, Timothy A.; Baldwin, D. J.; Paudyal, D.

    2017-11-01

    Theoretical understanding of interactions between localized and mobile electrons and the crystal environment in light lanthanides is important because of their key role in much needed magnetic anisotropy in permanent magnet materials that have a great impact in automobile and wind turbine applications. We report electronic, magnetic, and magnetocrystalline properties of these basic light lanthanide elements studied from advanced density functional theory (DFT) calculations. We find that the inclusion of onsite 4f electron correlation and spin orbit coupling within the full-potential band structure is needed to understand the unique magnetocrystalline properties of these light lanthanides. The onsite electron correlation, spin orbit coupling, and full potential for the asphericity of charge densities must be taken into account for the proper treatment of 4f states. We find the variation of total energy as a function of lattice constants that indicate multiple structural phases in Ce contrasting to a single stable structure obtained in other light lanthanides. The 4f orbital magnetic moments are partially quenched as a result of crystalline electric field splitting that leads to magnetocrystalline anisotropy. The charge density plots have similar asphericity and environment in Pr and Nd indicating similar magnetic anisotropy. However, Ce and Sm show completely different asphericity and environment as both orbital moments are significantly quenched. In addition, the Fermi surface structures exemplified in Nd indicate structural stability and unravel a cause of anisotropy. The calculated magnetocrystalline anisotropy energy (MAE) reveals competing c-axis and in-plane anisotropies, and also predicts possibilities of unusual structural deformations in light lanthanides. The uniaxial magnetic anisotropy is obtained in the double hexagonal closed pack structures of the most of the light lanthanides, however, the anisotropy is reduced or turned to planar in the low symmetry

  8. Osteoprotegerin levels in ST-elevation myocardial infarction: Temporal profile and association with myocardial injury and left ventricular function.

    Directory of Open Access Journals (Sweden)

    Christian Shetelig

    Full Text Available Elevated levels of osteoprotegerin (OPG have been associated with adverse outcomes in ST-elevation myocardial infarction (STEMI. However, the role of OPG in myocardial injury and adverse remodeling in STEMI patients remains unclear. The aims of this observational cohort study were to evaluate: 1 the temporal profile of OPG during STEMI, 2 possible associations between OPG measured acutely and after 4 months, with infarct size, adverse left ventricular (LV remodeling, microvascular obstruction (MVO and myocardial salvage and 3 the effect of heparin administration on OPG levels.Blood samples were drawn repeatedly from 272 STEMI patients treated with primary percutaneous coronary intervention (PCI. Cardiac magnetic resonance imaging (CMR was performed in the acute phase and after 4 months. The effect of heparin administration on OPG levels was studied in 20 patients referred to elective coronary angiography.OPG levels measured acutely were significantly higher than Day 1 and during follow-up. OPG levels were correlated with age. No association was found between early OPG levels and CMR measurements at 4 months. Patients with >median OPG levels measured at Day 1 had larger final infarct size, lower LV ejection fraction (LVEF at 4 months and higher frequency of MVO. There were no associations between OPG and change in end-diastolic volume or myocardial salvage. OPG remained associated with infarct size and LVEF after adjustment for relevant covariates, except peak troponin T and CRP. A 77% increase in OPG levels following heparin administration was found in patients undergoing elective coronary angiography.OPG was found to be associated with myocardial injury, but not with LV remodeling or myocardial salvage. The use of OPG as a biomarker in STEMI patients seems to be limited by a strong association with age, confounding effect of heparin administration, and little additive value to established biomarkers.

  9. Osteoprotegerin levels in ST-elevation myocardial infarction: Temporal profile and association with myocardial injury and left ventricular function

    Science.gov (United States)

    Shetelig, Christian; Limalanathan, Shanmuganathan; Eritsland, Jan; Hoffmann, Pavel; Seljeflot, Ingebjørg; Gran, Jon Michael; Aukrust, Pål; Ueland, Thor; Andersen, Geir Øystein

    2017-01-01

    Background Elevated levels of osteoprotegerin (OPG) have been associated with adverse outcomes in ST-elevation myocardial infarction (STEMI). However, the role of OPG in myocardial injury and adverse remodeling in STEMI patients remains unclear. The aims of this observational cohort study were to evaluate: 1) the temporal profile of OPG during STEMI, 2) possible associations between OPG measured acutely and after 4 months, with infarct size, adverse left ventricular (LV) remodeling, microvascular obstruction (MVO) and myocardial salvage and 3) the effect of heparin administration on OPG levels. Methods Blood samples were drawn repeatedly from 272 STEMI patients treated with primary percutaneous coronary intervention (PCI). Cardiac magnetic resonance imaging (CMR) was performed in the acute phase and after 4 months. The effect of heparin administration on OPG levels was studied in 20 patients referred to elective coronary angiography. Results OPG levels measured acutely were significantly higher than Day 1 and during follow-up. OPG levels were correlated with age. No association was found between early OPG levels and CMR measurements at 4 months. Patients with >median OPG levels measured at Day 1 had larger final infarct size, lower LV ejection fraction (LVEF) at 4 months and higher frequency of MVO. There were no associations between OPG and change in end-diastolic volume or myocardial salvage. OPG remained associated with infarct size and LVEF after adjustment for relevant covariates, except peak troponin T and CRP. A 77% increase in OPG levels following heparin administration was found in patients undergoing elective coronary angiography. Conclusions OPG was found to be associated with myocardial injury, but not with LV remodeling or myocardial salvage. The use of OPG as a biomarker in STEMI patients seems to be limited by a strong association with age, confounding effect of heparin administration, and little additive value to established biomarkers. PMID

  10. Physical modelling of elastic anisotropy in porous media

    Energy Technology Data Exchange (ETDEWEB)

    Furre, Anne-Kari

    1997-12-31

    During the last decades, anisotropy has become increasingly interesting in hydrocarbon prospecting. Knowledge of anisotropy in the subsurface can improve reservoir production and data interpretation. This thesis presents experimental studies of three different artificial anisotropic media: layered materials, isotropic matrix with stress-induced fractures, and layered media with controlled crack patterns at an oblique angle relative to layering. Layered media were constructed by varying grain size distributions for different layers, which resulted in acoustic and permeability anisotropy. The thin layer materials could be described by Backus modelling provided the wavelength was much larger than the layer periods. Frequency dependent scattering was observed for waves travelling normal to the layers. Saturated wave velocities were consistent with transverse isotropic Biot theory, but because the permeability anisotropy was small, no flow dependent attenuation anisotropy was observed. When sandstones were cemented under stress and then released, to simulate a vertical core or uplift process, predominantly horizontal cracks developed in the samples. On reloading to the cementing stress level, the velocities were below the initial values, which supports the theories of crack growth. In further triaxial tests on the same material a stress-dependent anisotropy occurred similar to what is often seen in natural samples taken from large depths. 70 refs., 200 figs., 56 tabs.

  11. Changes in reflectance anisotropy of wheat crop during different phenophases

    Science.gov (United States)

    Lunagaria, Manoj M.; Patel, Haridas R.

    2017-04-01

    The canopy structure of wheat changes significantly with growth stages and leads to changes in reflectance anisotropy. Bidirectional reflectance distribution function characterises the reflectance anisotropy of the targets, which can be approximated. Spectrodirectional reflectance measurements on wheat crop were acquired using a field goniometer system. The bidirectional reflectance spectra were acquired at 54 view angles to cover the hemispheric span up to 60° view zenith. The observations were made during early growth stages till maturity of the crop. The anisotropy was not constant for all wavelengths and anisotropic factors clearly revealed spectral dependence, which was more pronounced in near principal plane. In near infrared, wheat canopy expressed less reflectance anisotropy because of higher multiple scattering. The broad hotspot signature was noticeable in reflectance of canopy whenever view and solar angles were close. Distinct changes in bidirectional reflectance distribution function were observed during booting to flowering stages as the canopy achieves more uniformity, height and head emergence. The function clearly reveals bowl shape during heading to early milking growth stages of the crop. Late growth stages show less prominent gap and shadow effects. Anisotropy index revealed that wheat exhibits changes in reflectance anisotropy with phenological development and with spectral bands.

  12. Limits on the ions temperature anisotropy in turbulent intracluster medium

    Energy Technology Data Exchange (ETDEWEB)

    Santos-Lima, R. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Potsdam Univ. (Germany). Inst. fuer Physik und Astronomie; Univ. de Sao Paulo (Brazil). Inst. de Astronomia, Geofisica e Ciencias Atmosfericas; Yan, H. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Potsdam Univ. (Germany). Inst. fuer Physik und Astronomie; Gouveia Dal Pino, E.M. de [Univ. de Sao Paulo (Brazil). Inst. de Astronomia, Geofisica e Ciencias Atmosfericas; Lazarian, A. [Wisconsin Univ., Madison, WI (United States). Dept. of Astronomy

    2016-05-15

    Turbulence in the weakly collisional intracluster medium of galaxies (ICM) is able to generate strong thermal velocity anisotropies in the ions (with respect to the local magnetic field direction), if the magnetic moment of the particles is conserved in the absence of Coulomb collisions. In this scenario, the anisotropic pressure magnetohydrodynamic (AMHD) turbulence shows a very different statistical behaviour from the standard MHD one and is unable to amplify seed magnetic fields, in disagreement with previous cosmological MHD simulations which are successful to explain the observed magnetic fields in the ICM. On the other hand, temperature anisotropies can also drive plasma instabilities which can relax the anisotropy. This work aims to compare the relaxation rate with the growth rate of the anisotropies driven by the turbulence. We employ quasilinear theory to estimate the ions scattering rate due to the parallel firehose, mirror, and ion-cyclotron instabilities, for a set of plasma parameters resulting from AMHD simulations of the turbulent ICM. We show that the ICM turbulence can sustain only anisotropy levels very close to the instabilities thresholds. We argue that the AMHD model which bounds the anisotropies at the marginal stability levels can describe the Alfvenic turbulence cascade in the ICM.

  13. Anisotropy of 2A66 Al-Li Alloy Sheet

    Directory of Open Access Journals (Sweden)

    ZHANG Xian-feng

    2017-07-01

    Full Text Available The anisotropy and microstructures during aging treatment for 2A66 Al-Li alloy were studied by Brinell hardness, tensile testing, optical microscope(OM, scanning electron microscope(SEM and transmission electron microscope (TEM. The main factors which influence the anisotropy of mechanical properties were discussed. The results indicate that, before 165℃ peak-aged, the anisotropy of the mechanical properties of the 2A66 Al-Li alloy decreases gradually with the extension of aging time. When the alloy is over-aged, the anisotropy of the alloy increases; the anisotropy of ductility is more serious than that of strength. The IPA values of σb, σ0.2 and δ of the alloy reach the lowest value at 3.0%, 3.0% and 12.2% respectively at the time of peak aging (64h, and the alloy is also obtained with good plasticity and axial tensile properties. σb, σ0.2 and δ of the alloy are 526.5, 448.9MPa, 10.1% respectively. Under different heat treatment conditions, the general behavior of the anisotropy of 2A66 Al-Li alloy is as follows: longitudinal (0° and transverse (90° have the highest strength, 45° direction is the lowest strength; 45° direction specimen has the highest elongation, vertical and horizontal direction has the minimum elongation.

  14. Transient increase of fractional anisotropy in reversible vasogenic edema.

    Science.gov (United States)

    Kimura-Ohba, Shihoko; Yang, Yi; Thompson, Jeffrey; Kimura, Tomonori; Salayandia, Victor M; Cosse, Melissa; Yang, Yirong; Sillerud, Laurel O; Rosenberg, Gary A

    2016-10-01

    Brain vasogenic edema, involving disruption of the blood-brain barrier, is a common pathological condition in several neurological diseases, with a heterogeneous prognosis. It is sometimes reversible, as in posterior reversible encephalopathy syndrome, but often irreversible and our current clinical tools are insufficient to reveal its reversibility. Here, we show that increased fractional anisotropy in magnetic resonance imaging is associated with the reversibility of vasogenic edema. Spontaneously, hypertensive rats-stroke prone demonstrated posterior reversible encephalopathy syndrome-like acute encephalopathy in response to high-dose cyclosporine A treatment; the deteriorating neurological symptoms and worsening scores in behavioral tests, which were seen in acute phase, dissappered after recovery by cessation of cyclosporine A. In the acute phase of encephalopathy, the fractional anisotropy and apparent diffusion coefficient increased in areas with IgG leakage. This increase of fractional anisotropy occurred in the absence of demyelination: fluid leakage into the myelinated space increased the axial, but not the radial, diffusivity, resulting in the increased fractional anisotropy. This increased fractional anisotropy returned to pre-encephalopathy values in the recovery phase. Our results highlight the importance of the fractional anisotropy increase as a marker for the reversibility of brain edema, which can delineate the brain areas for which recovery is possible. © The Author(s) 2016.

  15. Magnetic anisotropies of (Ga,Mn)As films and nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Frank

    2011-02-02

    In this work the magnetic anisotropies of the diluted magnetic semiconductor (Ga,Mn)As were investigated experimentally. (Ga,Mn)As films show a superposition of various magnetic anisotropies which depend sensitively on various parameters such as temperature, carrier concentration or lattice strain. However, the anisotropies of lithographically prepared (Ga,Mn)As elements differ significantly from an unpatterned (Ga,Mn)As film. In stripe-shaped structures this behaviour is caused by anisotropic relaxation of the compressive lattice strain. In order to determine the magnetic anisotropies of individual (Ga,Mn)As nanostructures a combination of ferromagnetic resonance and time-resolved scanning Kerr microscopy was employed in this thesis. In addition, local changes of the magnetic anisotropy in circular and rectangular structures were visualized by making use of spatially resolved measurements. Finally, also the influence of the laterally inhomogeneous magnetic anisotropies on the static magnetic properties, such as coercive fields, was investigated employing spatially resolved static MOKE measurements on individual (Ga,Mn)As elements. (orig.)

  16. Anisotropies in the HI gas distribution toward 3C 196

    Science.gov (United States)

    Kalberla, P. M. W.; Kerp, J.

    2016-10-01

    Context. The local Galactic Hi gas was found to contain cold neutral medium (CNM) filaments that are aligned with polarized dust emission. These filaments appear to be dominated by the magnetic field and in this case turbulence is expected to show distinct anisotropies. Aims: We use the Galactic Effelsberg-Bonn Hi Survey (EBHIS) to derive 2D turbulence spectra for the Hi distribution in direction to 3C 196 and two more comparison fields. Methods: Prior to Fourier transform we apply a rotational symmetric 50% Tukey window to apodize the data. We derive average as well as position angle dependent power spectra. Anisotropies in the power distribution are defined as the ratio of the spectral power in orthogonal directions. Results: We find strong anisotropies. For a narrow range in position angle, in direction perpendicular to the filaments and the magnetic field, the spectral power is on average more than an order of magnitude larger than parallel. In the most extreme case the anisotropy reaches locally a factor of 130. Anisotropies increase on average with spatial frequency as predicted by Goldreich & Sridhar (1995, ApJ, 438, 763), at the same time the Kolmogorov spectral index remains almost unchanged. The strongest anisotropies are observable for a narrow range in velocity and decay with a power law index close to -8/3, almost identical to the average isotropic spectral index of -2.9 Faraday depth.

  17. Energetic Electrons in Dipolarization Events: Spatial Properties and Anisotropy

    Science.gov (United States)

    Birn, J.; Runov, A.; Hesse, M.

    2014-01-01

    Using the electromagnetic fields of an MHD simulation of magnetotail reconnection, flow bursts, and dipolarization, we further investigate the acceleration of electrons to suprathermal energies. Particular emphasis is on spatial properties and anisotropies as functions of energy and time. The simulation results are compared with Time History of Events and Macroscale Interactions during Substorms observations. The test particle approach successfully reproduces several observed injection features and puts them into a context of spatial maps of the injection region(s): a dominance of perpendicular anisotropies farther down the tail and closer to the equatorial plane, an increasing importance of parallel anisotropy closer to Earth and at higher latitudes, a drop in energy fluxes at energies below approximately 10 keV, coinciding with the plasma density drop, together with increases at higher energy, a triple peak structure of flux increases near 0 deg, 90 deg, and 180 deg, and a tendency of flux increases to extend to higher energy closer to Earth and at lower latitudes. We identified the plasma sheet boundary layers and adjacent lobes as a main source region for both increased and decreased energetic electron fluxes, related to the different effects of adiabatic acceleration at high and low energies. The simulated anisotropies tend to exceed the observed ones, particularly for perpendicular fluxes at high energies. The most plausible reason is that the MHD simulation lacks the effects of anisotropy-driven microinstabilities and waves, which would reduce anisotropies.

  18. Biomaterial strategies for alleviation of myocardial infarction

    Science.gov (United States)

    Venugopal, Jayarama Reddy; Prabhakaran, Molamma P.; Mukherjee, Shayanti; Ravichandran, Rajeswari; Dan, Kai; Ramakrishna, Seeram

    2012-01-01

    World Health Organization estimated that heart failure initiated by coronary artery disease and myocardial infarction (MI) leads to 29 per cent of deaths worldwide. Heart failure is one of the leading causes of death in industrialized countries and is expected to become a global epidemic within the twenty-first century. MI, the main cause of heart failure, leads to a loss of cardiac tissue impairment of left ventricular function. The damaged left ventricle undergoes progressive ‘remodelling’ and chamber dilation, with myocyte slippage and fibroblast proliferation. Repair of diseased myocardium with in vitro-engineered cardiac muscle patch/injectable biopolymers with cells may become a viable option for heart failure patients. These events reflect an apparent lack of effective intrinsic mechanism for myocardial repair and regeneration. Motivated by the desire to develop minimally invasive procedures, the last 10 years observed growing efforts to develop injectable biomaterials with and without cells to treat cardiac failure. Biomaterials evaluated include alginate, fibrin, collagen, chitosan, self-assembling peptides, biopolymers and a range of synthetic hydrogels. The ultimate goal in therapeutic cardiac tissue engineering is to generate biocompatible, non-immunogenic heart muscle with morphological and functional properties similar to natural myocardium to repair MI. This review summarizes the properties of biomaterial substrates having sufficient mechanical stability, which stimulates the native collagen fibril structure for differentiating pluripotent stem cells and mesenchymal stem cells into cardiomyocytes for cardiac tissue engineering. PMID:21900319

  19. The variation of linewidth in exchange coupled bilayer films with stress anisotropy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lei [Inner Mongolia Key Lab of Nanoscience and Nanotechnology and School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021 (China); Rong, Jianhong, E-mail: jhrong502@163.com [Inner Mongolia Key Lab of Nanoscience and Nanotechnology and School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021 (China); Yun, Guohong, E-mail: ndghyun@imu.edu.cn [Inner Mongolia Key Lab of Nanoscience and Nanotechnology and School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021 (China); College of Physics and Electronic Information, Inner Mongolia Normal University, Hohhot 010022 (China); Wang, Dong; Bao, Lingbo [Inner Mongolia Key Lab of Nanoscience and Nanotechnology and School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021 (China)

    2016-12-01

    The frequency linewidth and the field linewidth in ferromagnetic/antiferromagnetic bilayer films with stress anisotropy have been investigated by using ferromagnetic resonance method. The effects of the stress anisotropy for in-plane anisotropy, weak and strong perpendicular anisotropy on linewidth are observed. It is found that the frequency and the field linewidth all increase for in-plane and weak perpendicular anisotropy, as the stress anisotropy field increases. And furthermore, the stress anisotropy field affects obviously the frequency and the field linewidth for unsaturation field.

  20. Characterization of optical anisotropy in quantum wells under compressive anisotropic in-plane strain

    Energy Technology Data Exchange (ETDEWEB)

    Biermann, Mark L [Physics Department, 566 Brownson Rd., U.S. Naval Academy, Annapolis, MD 21402 (United States); Walters, Matthew [Physics Department, 566 Brownson Rd., U.S. Naval Academy, Annapolis, MD 21402 (United States); Diaz-Barriga, James [Physics Department, 566 Brownson Rd., U.S. Naval Academy, Annapolis, MD 21402 (United States); Rabinovich, W S [Naval Research Laboratory, Code 5652, 4555 Overlook Ave. SW, Washington, DC 20375-5320 (United States)

    2003-10-21

    Anisotropic in-plane strain in quantum wells leads to an optical polarization anisotropy that can be exploited for device applications. We have determined that for many anisotropic compressive strain cases, the dependence of the optical anisotropy is linear in the strain anisotropy. This result holds for a variety of well and barrier materials and widths and for various overall strain conditions. Further, the polarization anisotropy per strain anisotropy varies as the reciprocal of the energy separation of the relevant hole sub-bands. Hence, a general result for the polarization anisotropy per strain anisotropy is available for cases of compressive anisotropic in-plane strain.

  1. In vivo study of myocardial elastography under graded ischemia conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Wei-Ning; Provost, Jean; Konofagou, Elisa E [Department of Biomedical Engineering, Columbia University, New York, NY (United States); Fujikura, Kana [Department of Radiology, Columbia University, New York, NY (United States); Wang Jie, E-mail: ek2191@columbia.edu [Department of Medicine, Columbia University, New York, NY (United States)

    2011-02-21

    The capability of currently available echocardiography-based strain estimation techniques to fully map myocardial abnormality at early stages of myocardial ischemia is yet to be investigated. In this study, myocardial elastography (ME), a radio-frequency (RF)-based strain imaging technique that maps the full 2D transmural angle-independent strain tensor in standard echocardiographic views at both high spatial and temporal resolution is presented. The objectives were to (1) evaluate the performance of ME on mapping the onset, extent and progression of myocardial ischemia at graded coronary constriction levels (from partial to complete coronary flow reduction), and (2) validate the accuracy of the strain estimates against sonomicrometry (SM) measurements. A non-survival canine ischemic model (n = 5) was performed by gradually constricting the left anterior descending (LAD) coronary blood flow from 0% (baseline blood flow) to 100% (zero blood flow) at 20% increments. An open-architecture ultrasound system was used to acquire RF echocardiograms in a standard full short-axis view at the frame rate of 211 fps, at least twice higher than what is typically used in conventional echocardiographic systems, using a previously developed, fully automated composite technique. Myocardial deformation was estimated by ME and validated against sonomicrometry. ME estimates and maps transmural (1) 2D displacements using RF cross-correlation and recorrelation; and (2) 2D polar (radial and circumferential) strains, derived from 2D (i.e. both lateral and axial) displacement components, at high accuracy. Full-view strain images were shown and found to reliably depict decreased myocardial function in the region at risk at increased levels of coronary flow reduction. The ME radial strain was deemed to be a more sensitive, quantitative, regional measure of myocardial ischemia as a result of coronary flow reduction when compared to the conventional wall motion score index and ejection fraction

  2. In vivo study of myocardial elastography under graded ischemia conditions

    Science.gov (United States)

    Lee, Wei-Ning; Provost, Jean; Fujikura, Kana; Wang, Jie; Konofagou, Elisa E.

    2011-02-01

    The capability of currently available echocardiography-based strain estimation techniques to fully map myocardial abnormality at early stages of myocardial ischemia is yet to be investigated. In this study, myocardial elastography (ME), a radio-frequency (RF)-based strain imaging technique that maps the full 2D transmural angle-independent strain tensor in standard echocardiographic views at both high spatial and temporal resolution is presented. The objectives were to (1) evaluate the performance of ME on mapping the onset, extent and progression of myocardial ischemia at graded coronary constriction levels (from partial to complete coronary flow reduction), and (2) validate the accuracy of the strain estimates against sonomicrometry (SM) measurements. A non-survival canine ischemic model (n = 5) was performed by gradually constricting the left anterior descending (LAD) coronary blood flow from 0% (baseline blood flow) to 100% (zero blood flow) at 20% increments. An open-architecture ultrasound system was used to acquire RF echocardiograms in a standard full short-axis view at the frame rate of 211 fps, at least twice higher than what is typically used in conventional echocardiographic systems, using a previously developed, fully automated composite technique. Myocardial deformation was estimated by ME and validated against sonomicrometry. ME estimates and maps transmural (1) 2D displacements using RF cross-correlation and recorrelation; and (2) 2D polar (radial and circumferential) strains, derived from 2D (i.e. both lateral and axial) displacement components, at high accuracy. Full-view strain images were shown and found to reliably depict decreased myocardial function in the region at risk at increased levels of coronary flow reduction. The ME radial strain was deemed to be a more sensitive, quantitative, regional measure of myocardial ischemia as a result of coronary flow reduction when compared to the conventional wall motion score index and ejection fraction

  3. Determinants and consequences of renal function variations with aldosterone blocker therapy in heart failure patients after myocardial infarction

    DEFF Research Database (Denmark)

    Rossignol, Patrick; Cleland, John G F; Bhandari, Sunil

    2012-01-01

    We evaluated the effect of the selective mineralocorticoid receptor antagonist eplerenone on renal function and the interaction between changes in renal function and subsequent cardiovascular outcomes in patients with heart failure and left ventricular systolic dysfunction after an acute myocardial...... infarction in the Eplerenone Post-Acute Myocardial Infarction Heart Failure Efficacy and Survival Study (EPHESUS)....

  4. Analysis of myocardial perfusion parameters in an ex-vivo porcine heart model using third generation dual-source CT

    NARCIS (Netherlands)

    Pelgrim, Gert Jan; Duguay, Taylor M; Stijnen, J Marco A; Varga-Szemes, Akos; Van Tuijl, Sjoerd; Schoepf, U Joseph; Oudkerk, Matthijs; Vliegenthart, Rozemarijn

    2017-01-01

    PURPOSE: To evaluate the relationship between fractional flow reserve (FFR)-determined coronary artery stenosis severity and myocardial perfusion parameters derived from dynamic myocardial CT perfusion imaging (CTP) in an ex-vivo porcine heart model. METHODS: Six porcine hearts were perfused

  5. Gradient Spin Echo (GraSE) imaging for fast myocardial T2 mapping.

    Science.gov (United States)

    Sprinkart, Alois M; Luetkens, Julian A; Träber, Frank; Doerner, Jonas; Gieseke, Jürgen; Schnackenburg, Bernhard; Schmitz, Georg; Thomas, Daniel; Homsi, Rami; Block, Wolfgang; Schild, Hans; Naehle, Claas P

    2015-02-12

    Quantitative Cardiovascular Magnetic Resonance (CMR) techniques have gained high interest in CMR research. Myocardial T2 mapping is thought to be helpful in diagnosis of acute myocardial conditions associated with myocardial edema. In this study we aimed to establish a technique for myocardial T2 mapping based on gradient-spin-echo (GraSE) imaging. The local ethics committee approved this prospective study. Written informed consent was obtained from all subjects prior to CMR. A modified GraSE sequence allowing for myocardial T2 mapping in a single breath-hold per slice using ECG-triggered acquisition of a black blood multi-echo series was developed at 1.5 Tesla. Myocardial T2 relaxation time (T2-RT) was determined by maximum likelihood estimation from magnitude phased-array multi-echo data. Four GraSE sequence variants with varying number of acquired echoes and resolution were evaluated in-vitro and in 20 healthy volunteers. Inter-study reproducibility was assessed in a subset of five volunteers. The sequence with the best overall performance was further evaluated by assessment of intra- and inter-observer agreement in all volunteers, and then implemented into the clinical CMR protocol of five patients with acute myocardial injury (myocarditis, takotsubo cardiomyopathy and myocardial infarction). In-vitro studies revealed the need for well defined sequence settings to obtain accurate T2-RT measurements with GraSE. An optimized 6-echo GraSE sequence yielded an excellent agreement with the gold standard Carr-Purcell-Meiboom-Gill sequence. Global myocardial T2 relaxation times in healthy volunteers was 52.2 ± 2.0 ms (mean ± standard deviation). Mean difference between repeated examinations (n = 5) was -0.02 ms with 95% limits of agreement (LoA) of [-4.7; 4.7] ms. Intra-reader and inter-reader agreement was excellent with mean differences of -0.1 ms, 95% LoA = [-1.3; 1.2] ms and 0.1 ms, 95% LoA = [-1.5; 1.6] ms, respectively (n = 20). In

  6. Stiffness Matrices and Anisotropy in the Trapezoidal Corrugated Composite Sheets

    Directory of Open Access Journals (Sweden)

    Mohammad Golzar

    2013-10-01

    Full Text Available In the some applications like as morphing technology, high strain and anisotropic behavior are essential design requirements. The corrugated composite sheets due to their special geometries have potential to high deflection under axial loading through longitudinal direction of corrugation. In this research, the strain and the anisotropic behavior of corrugated composite sheets are investigated by fabricating glass/epoxy samples with trapezoidal geometries. For evaluation of the mechanical behavior of the composites the samples were subjected to tension and flexural tests in the longitudinal and transverse directions of corrugation. In order to determine anisotropic behavior of the corrugated sheets, two approaches were