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Sample records for accurately reflect cardiac

  1. Accurate measurement of oxygen consumption in children undergoing cardiac catheterization.

    Li, Jia

    2013-01-01

    Oxygen consumption (VO(2) ) is an important part of hemodynamics using the direct Fick principle in children undergoing cardiac catheterization. Accurate measurement of VO(2) is vital. Obviously, any error in the measurement of VO(2) will translate directly into an equivalent percentage under- or overestimation of blood flows and vascular resistances. It remains common practice to estimate VO(2) values from published predictive equations. Among these, the LaFarge equation is the most commonly used equation and gives the closest estimation with the least bias and limits of agreement. However, considerable errors are introduced by the LaFarge equation, particularly in children younger than 3 years of age. Respiratory mass spectrometry remains the "state-of-the-art" method, allowing highly sensitive, rapid and simultaneous measurement of multiple gas fractions. The AMIS 2000 quadrupole respiratory mass spectrometer system has been adapted to measure VO(2) in children under mechanical ventilation with pediatric ventilators during cardiac catheterization. The small sampling rate, fast response time and long tubes make the equipment a unique and powerful tool for bedside continuous measurement of VO(2) in cardiac catheterization for both clinical and research purposes. PMID:22488802

  2. Standardized EEG interpretation accurately predicts prognosis after cardiac arrest

    Westhall, Erik; Rossetti, Andrea O; van Rootselaar, Anne-Fleur; Wesenberg Kjaer, Troels; Horn, Janneke; Ullén, Susann; Friberg, Hans; Nielsen, Niklas; Rosén, Ingmar; Åneman, Anders; Erlinge, David; Gasche, Yvan; Hassager, Christian; Hovdenes, Jan; Kjaergaard, Jesper; Kuiper, Michael; Pellis, Tommaso; Stammet, Pascal; Wanscher, Michael; Wetterslev, Jørn; Wise, Matt P; Cronberg, Tobias

    2016-01-01

    OBJECTIVE: To identify reliable predictors of outcome in comatose patients after cardiac arrest using a single routine EEG and standardized interpretation according to the terminology proposed by the American Clinical Neurophysiology Society. METHODS: In this cohort study, 4 EEG specialists......, blinded to outcome, evaluated prospectively recorded EEGs in the Target Temperature Management trial (TTM trial) that randomized patients to 33°C vs 36°C. Routine EEG was performed in patients still comatose after rewarming. EEGs were classified into highly malignant (suppression, suppression with...... periodic discharges, burst-suppression), malignant (periodic or rhythmic patterns, pathological or nonreactive background), and benign EEG (absence of malignant features). Poor outcome was defined as best Cerebral Performance Category score 3-5 until 180 days. RESULTS: Eight TTM sites randomized 202...

  3. Standardized EEG interpretation accurately predicts prognosis after cardiac arrest

    Rossetti, Andrea O.; van Rootselaar, Anne-Fleur; Wesenberg Kjaer, Troels; Horn, Janneke; Ullén, Susann; Friberg, Hans; Nielsen, Niklas; Rosén, Ingmar; Åneman, Anders; Erlinge, David; Gasche, Yvan; Hassager, Christian; Hovdenes, Jan; Kjaergaard, Jesper; Kuiper, Michael; Pellis, Tommaso; Stammet, Pascal; Wanscher, Michael; Wetterslev, Jørn; Wise, Matt P.; Cronberg, Tobias

    2016-01-01

    Objective: To identify reliable predictors of outcome in comatose patients after cardiac arrest using a single routine EEG and standardized interpretation according to the terminology proposed by the American Clinical Neurophysiology Society. Methods: In this cohort study, 4 EEG specialists, blinded to outcome, evaluated prospectively recorded EEGs in the Target Temperature Management trial (TTM trial) that randomized patients to 33°C vs 36°C. Routine EEG was performed in patients still comatose after rewarming. EEGs were classified into highly malignant (suppression, suppression with periodic discharges, burst-suppression), malignant (periodic or rhythmic patterns, pathological or nonreactive background), and benign EEG (absence of malignant features). Poor outcome was defined as best Cerebral Performance Category score 3–5 until 180 days. Results: Eight TTM sites randomized 202 patients. EEGs were recorded in 103 patients at a median 77 hours after cardiac arrest; 37% had a highly malignant EEG and all had a poor outcome (specificity 100%, sensitivity 50%). Any malignant EEG feature had a low specificity to predict poor prognosis (48%) but if 2 malignant EEG features were present specificity increased to 96% (p < 0.001). Specificity and sensitivity were not significantly affected by targeted temperature or sedation. A benign EEG was found in 1% of the patients with a poor outcome. Conclusions: Highly malignant EEG after rewarming reliably predicted poor outcome in half of patients without false predictions. An isolated finding of a single malignant feature did not predict poor outcome whereas a benign EEG was highly predictive of a good outcome. PMID:26865516

  4. An accurately fast algorithm of calculating reflection/transmission coefficients

    CASTAGNA; J; P

    2008-01-01

    For the boundary between transversely isotropic media with a vertical axis of symmetry (VTI media), the interface between a liquid and a VTI medium, and the free-surface of an elastic half-space of a VTI medium, an accurately fast algorithm was presented for calculating reflection/transmission (R/T) coefficients. Specially, the case of post-critical angle incidence was considered. Although we only performed the numerical calculation for the models of the VTI media, the calculated results can be extended to the models of transversely isotropic media with a horizontal axis of rotation symmetry (HTI media). Compared to previous work, this algorithm can be used not only for the calculation of R/T coefficients of the boundary between ellipsoidally anisotropic media, but also for that between generally anisotropic media, and the speed and accuracy of this algorithm are faster and higher. According to the anisotropic parameters of some rocks given by the published literature, we performed the calculation of R/T coefficients by using this algorithm and analyzed the effect of the rock anisotropy on R/T coefficients. We used Snell’s law and the energy balance principle to perform verification for the calculated results.

  5. OSEM in accurate evaluation of CAD using cardiac SPECT

    Filtered Backprojection (FBP) has been used as standard processing method for almost all of the SPECT studies. Recently, iterative algorithms such as MLEM and the newest one, Ordered Subset Expectation Maximization (OSEM) introduced as an alternative method to reconstruction and applied for many SPECT studies like brain, bone, and...Application of this method in car dia SPECT was restricted merely in some of research centers. However, does iterative reconstruction as compared to FBP increase the accuracy of myocardial perfusion SPECT in evaluation of coronary artery disease? We aimed to investigate the diagnostic performance of OSEM over FBP. 15 coronary artery diseased patients underwent stress/rest cardiac perfusion study. The images were obtained by SMV SPECT system and two-day protocol was performed. Each raw data was processed by both methods. FBP was done with a METZ 4 filter and iterative reconstruction was done with the OSEM software (5 iterative, 16-10 iterative, 32-5 iterative, 16 and...) without any truncation. Comparison of OSEM versus FBP was performed both visually and quantitatively used a square ROI over each of 8 segments of LV and a mean activity ratio (defect to normal ratio) and signal to noise (Bk g. activity) were obtained. All quantitatively parameters were analyzed with SPSS software statistically and correlation coefficient was calculated upon Pear son's correlation formula. Kean correlation coefficient value between OSEM and FBP was high (r2=0/96) when an negative number of 5 was used. Difference value for mean of D/N activity was <2.5% and for in count ratio was low (4%). Visually, the image quality was rather high in preference of OSEM to FBP. the above results revealed similarity between these two methods with reduction of noise in OSEM reconstructed images, and indicated that OSEM can provide improvement in accuracy if co per number of iteration and subset level were selected. The obtained results concluded that OSEM could be used as

  6. Accurate Measurements of Spectral Reflectance in Picasso's Guernica Painting.

    de Luna, Javier Muñoz; Fernandez-Balbuena, Antonio Alvarez; Vázquez, Daniel; Melgosa, Manuel; Durán, Humberto; García, Jorge; Muro, Carmen

    2016-01-01

    The use of non-invasive spectral measurements to control the conservation status is a part of the preventive conservation of artworks which nowadays is becoming increasingly interesting. This paper describes how to use a spectral measuring device and an illumination system specifically designed for such a task in a very large dimension artwork painting (7.8 m wide × 3.5 m high). The system, controlled by a Cartesian robot, allows spectral measurements in a spectral range of 400-780 nm. The measured data array has a total of 2201 circular regions with 5.5 mm spot diameter placed on a square grid. Colorimetric calculations performed from these spectral measurements may be used to characterize color shifts related to reflectance changes in specific areas of the paint. A color shifting from the expected gray has been shown. PMID:26767640

  7. Osteoprotegerin Levels Change During STEMI and Reflect Cardiac Function

    Lindberg, Søren; Jensen, Jan S; Hoffmann, Søren; Iversen, Allan Z; Pedersen, Sune H; Mogelvang, Rasmus; Galatius, Søren; Flyvbjerg, Allan; Bjerre, Mette

    2014-01-01

    BACKGROUND: High levels of circulating osteoprotegerin (OPG) predicts long-term outcome in patients with ST-elevation myocardial infarction (STEMI), possibly because of increased vascular inflammation resulting in myocardial damage. In the present study we aimed at elucidating the dynamic progress...... of OPG levels during STEMI treated with percutaneous coronary intervention (PCI) and additionally, the effect of OPG levels on cardiac function. METHODS: We prospectively included 42 patients with STEMI treated with primary PCI. Four consecutive blood samples were obtained before and after PCI...... treatment. Plasma OPG levels were determined using an in-house immunoassay. Cardiac function was increased according to echocardiography, estimating left ventricular ejection fraction (LVEF) 1-3 days after STEMI. RESULTS: During STEMI, OPG levels peaked after PCI and then decreased; mean concentrations (95...

  8. Should scatter be corrected in both transmission and emission data for accurate quantitation in cardiac SPET?

    Ideally, reliable quantitation in single-photon emission tomography (SPET) requires both emission and transmission data to be scatter free. Although scatter in emission data has been extensively studied, it is not well known how scatter in transmission data affects relative and absolute quantitation in reconstructed images. We studied SPET quantitative accuracy for different amounts of scatter in emission and transmission data using a Utah phantom and a cardiac Data Spectrum phantom including different attenuating media. Acquisitions over 180 were considered and three projection sets were derived: 20% images and Jaszczak and triple-energy-window scatter-corrected projections. Transmission data were acquired using gadolinium-153 line sources in a 90-110 keV window using a narrow or wide scanning window. The transmission scans were performed either simultaneously with the emission acquisition or 24 h later. Transmission maps were reconstructed using filtered backprojection and μ values were linearly scaled from 100 to 140 keV. Attenuation-corrected images were reconstructed using a conjugate gradient minimal residual algorithm. The μ value underestimation varied between 4% with a narrow transmission window in soft tissue and 22% with a wide window in a material simulating bone. Scatter in the emission and transmission data had little effect on the uniformity of activity distribution in the left ventricle wall and in a uniformly hot compartment of the Utah phantom. Correcting the transmission data for scatter had no impact on contrast between a hot and a cold region or on signal-to-noise ratio (SNR) in regions with uniform activity distribution, while correcting the emission data for scatter improved contrast and reduced SNR. For absolute quantitation, the most accurate results (bias <4% in both phantoms) were obtained when reducing scatter in both emission and transmission data. In conclusion, trying to obtain the same amount of scatter in emission and transmission

  9. Should scatter be corrected in both transmission and emission data for accurate quantitation in cardiac SPET?

    Fakhri, G.E. [Harvard Medical School, Boston, MA (United States). Dept. of Radiology; U494 INSERM, CHU Pitie-Salpetriere, Paris (France); Buvat, I.; Todd-Pokropek, A.; Benali, H. [U494 INSERM, CHU Pitie-Salpetriere, Paris (France); Almeida, P. [Servico de Medicina Nuclear, Hospital Garcia de Orta, Almada (Portugal); Bendriem, B. [CTI, Inc., Knoxville, TN (United States)

    2000-09-01

    Ideally, reliable quantitation in single-photon emission tomography (SPET) requires both emission and transmission data to be scatter free. Although scatter in emission data has been extensively studied, it is not well known how scatter in transmission data affects relative and absolute quantitation in reconstructed images. We studied SPET quantitative accuracy for different amounts of scatter in emission and transmission data using a Utah phantom and a cardiac Data Spectrum phantom including different attenuating media. Acquisitions over 180 were considered and three projection sets were derived: 20% images and Jaszczak and triple-energy-window scatter-corrected projections. Transmission data were acquired using gadolinium-153 line sources in a 90-110 keV window using a narrow or wide scanning window. The transmission scans were performed either simultaneously with the emission acquisition or 24 h later. Transmission maps were reconstructed using filtered backprojection and {mu} values were linearly scaled from 100 to 140 keV. Attenuation-corrected images were reconstructed using a conjugate gradient minimal residual algorithm. The {mu} value underestimation varied between 4% with a narrow transmission window in soft tissue and 22% with a wide window in a material simulating bone. Scatter in the emission and transmission data had little effect on the uniformity of activity distribution in the left ventricle wall and in a uniformly hot compartment of the Utah phantom. Correcting the transmission data for scatter had no impact on contrast between a hot and a cold region or on signal-to-noise ratio (SNR) in regions with uniform activity distribution, while correcting the emission data for scatter improved contrast and reduced SNR. For absolute quantitation, the most accurate results (bias <4% in both phantoms) were obtained when reducing scatter in both emission and transmission data. In conclusion, trying to obtain the same amount of scatter in emission and

  10. Computational Chemical Imaging for Cardiovascular Pathology: Chemical Microscopic Imaging Accurately Determines Cardiac Transplant Rejection

    Tiwari, Saumya; Reddy, Vijaya B.; Bhargava, Rohit; Raman, Jaishankar

    2015-01-01

    Rejection is a common problem after cardiac transplants leading to significant number of adverse events and deaths, particularly in the first year of transplantation. The gold standard to identify rejection is endomyocardial biopsy. This technique is complex, cumbersome and requires a lot of expertise in the correct interpretation of stained biopsy sections. Traditional histopathology cannot be used actively or quickly during cardiac interventions or surgery. Our objective was to develop a st...

  11. Measuring solar reflectance Part I: Defining a metric that accurately predicts solar heat gain

    Levinson, Ronnen; Akbari, Hashem; Berdahl, Paul

    2010-05-14

    Solar reflectance can vary with the spectral and angular distributions of incident sunlight, which in turn depend on surface orientation, solar position and atmospheric conditions. A widely used solar reflectance metric based on the ASTM Standard E891 beam-normal solar spectral irradiance underestimates the solar heat gain of a spectrally selective 'cool colored' surface because this irradiance contains a greater fraction of near-infrared light than typically found in ordinary (unconcentrated) global sunlight. At mainland U.S. latitudes, this metric RE891BN can underestimate the annual peak solar heat gain of a typical roof or pavement (slope {le} 5:12 [23{sup o}]) by as much as 89 W m{sup -2}, and underestimate its peak surface temperature by up to 5 K. Using R{sub E891BN} to characterize roofs in a building energy simulation can exaggerate the economic value N of annual cool-roof net energy savings by as much as 23%. We define clear-sky air mass one global horizontal ('AM1GH') solar reflectance R{sub g,0}, a simple and easily measured property that more accurately predicts solar heat gain. R{sub g,0} predicts the annual peak solar heat gain of a roof or pavement to within 2 W m{sup -2}, and overestimates N by no more than 3%. R{sub g,0} is well suited to rating the solar reflectances of roofs, pavements and walls. We show in Part II that R{sub g,0} can be easily and accurately measured with a pyranometer, a solar spectrophotometer or version 6 of the Solar Spectrum Reflectometer.

  12. Computational Chemical Imaging for Cardiovascular Pathology: Chemical Microscopic Imaging Accurately Determines Cardiac Transplant Rejection

    Tiwari, Saumya; Reddy, Vijaya B.; Bhargava, Rohit; Raman, Jaishankar

    2015-01-01

    Rejection is a common problem after cardiac transplants leading to significant number of adverse events and deaths, particularly in the first year of transplantation. The gold standard to identify rejection is endomyocardial biopsy. This technique is complex, cumbersome and requires a lot of expertise in the correct interpretation of stained biopsy sections. Traditional histopathology cannot be used actively or quickly during cardiac interventions or surgery. Our objective was to develop a stain-less approach using an emerging technology, Fourier transform infrared (FT-IR) spectroscopic imaging to identify different components of cardiac tissue by their chemical and molecular basis aided by computer recognition, rather than by visual examination using optical microscopy. We studied this technique in assessment of cardiac transplant rejection to evaluate efficacy in an example of complex cardiovascular pathology. We recorded data from human cardiac transplant patients’ biopsies, used a Bayesian classification protocol and developed a visualization scheme to observe chemical differences without the need of stains or human supervision. Using receiver operating characteristic curves, we observed probabilities of detection greater than 95% for four out of five histological classes at 10% probability of false alarm at the cellular level while correctly identifying samples with the hallmarks of the immune response in all cases. The efficacy of manual examination can be significantly increased by observing the inherent biochemical changes in tissues, which enables us to achieve greater diagnostic confidence in an automated, label-free manner. We developed a computational pathology system that gives high contrast images and seems superior to traditional staining procedures. This study is a prelude to the development of real time in situ imaging systems, which can assist interventionists and surgeons actively during procedures. PMID:25932912

  13. Computational chemical imaging for cardiovascular pathology: chemical microscopic imaging accurately determines cardiac transplant rejection.

    Saumya Tiwari

    Full Text Available Rejection is a common problem after cardiac transplants leading to significant number of adverse events and deaths, particularly in the first year of transplantation. The gold standard to identify rejection is endomyocardial biopsy. This technique is complex, cumbersome and requires a lot of expertise in the correct interpretation of stained biopsy sections. Traditional histopathology cannot be used actively or quickly during cardiac interventions or surgery. Our objective was to develop a stain-less approach using an emerging technology, Fourier transform infrared (FT-IR spectroscopic imaging to identify different components of cardiac tissue by their chemical and molecular basis aided by computer recognition, rather than by visual examination using optical microscopy. We studied this technique in assessment of cardiac transplant rejection to evaluate efficacy in an example of complex cardiovascular pathology. We recorded data from human cardiac transplant patients' biopsies, used a Bayesian classification protocol and developed a visualization scheme to observe chemical differences without the need of stains or human supervision. Using receiver operating characteristic curves, we observed probabilities of detection greater than 95% for four out of five histological classes at 10% probability of false alarm at the cellular level while correctly identifying samples with the hallmarks of the immune response in all cases. The efficacy of manual examination can be significantly increased by observing the inherent biochemical changes in tissues, which enables us to achieve greater diagnostic confidence in an automated, label-free manner. We developed a computational pathology system that gives high contrast images and seems superior to traditional staining procedures. This study is a prelude to the development of real time in situ imaging systems, which can assist interventionists and surgeons actively during procedures.

  14. Accurate segmentation framework for the left ventricle wall from cardiac cine MRI

    Sliman, H.; Khalifa, F.; Elnakib, A.; Soliman, A.; Beache, G. M.; Gimel'farb, G.; Emam, A.; Elmaghraby, A.; El-Baz, A.

    2013-10-01

    We propose a novel, fast, robust, bi-directional coupled parametric deformable model to segment the left ventricle (LV) wall borders using first- and second-order visual appearance features. These features are embedded in a new stochastic external force that preserves the topology of LV wall to track the evolution of the parametric deformable models control points. To accurately estimate the marginal density of each deformable model control point, the empirical marginal grey level distributions (first-order appearance) inside and outside the boundary of the deformable model are modeled with adaptive linear combinations of discrete Gaussians (LCDG). The second order visual appearance of the LV wall is accurately modeled with a new rotationally invariant second-order Markov-Gibbs random field (MGRF). We tested the proposed segmentation approach on 15 data sets in 6 infarction patients using the Dice similarity coefficient (DSC) and the average distance (AD) between the ground truth and automated segmentation contours. Our approach achieves a mean DSC value of 0.926±0.022 and AD value of 2.16±0.60 compared to two other level set methods that achieve 0.904±0.033 and 0.885±0.02 for DSC; and 2.86±1.35 and 5.72±4.70 for AD, respectively.

  15. Accurate wavelength prediction of photonic crystal resonant reflection and applications in refractive index measurement

    Hermannsson, Pétur Gordon; Vannahme, Christoph; Smith, Cameron L. C.;

    2014-01-01

    superstrate materials. The importance of accounting for material dispersion in order to obtain accurate simulation results is highlighted, and a method for doing so using an iterative approach is demonstrated. Furthermore, an application for the model is demonstrated, in which the material dispersion of a...

  16. Cardiac MRI tagging

    Cardiac MRI tagging is an original technique based upon the perturbation of the magnetization of determined regions of the myocardium (tags). The motion of the tags accurately reflects the deformation of the underlying tissue. Data analysis requires special techniques to reconstruct the 3D motion of the heart, and to evaluate the myocardial strain, locally and throughout the whole heart. (authors)

  17. Calcium Transients Closely Reflect Prolonged Action Potentials in iPSC Models of Inherited Cardiac Arrhythmia

    C. Ian Spencer

    2014-08-01

    Full Text Available Long-QT syndrome mutations can cause syncope and sudden death by prolonging the cardiac action potential (AP. Ion channels affected by mutations are various, and the influences of cellular calcium cycling on LQTS cardiac events are unknown. To better understand LQTS arrhythmias, we performed current-clamp and intracellular calcium ([Ca2+]i measurements on cardiomyocytes differentiated from patient-derived induced pluripotent stem cells (iPS-CM. In myocytes carrying an LQT2 mutation (HERG-A422T, APs and [Ca2+]i transients were prolonged in parallel. APs were abbreviated by nifedipine exposure and further lengthened upon releasing intracellularly stored Ca2+. Validating this model, control iPS-CM treated with HERG-blocking drugs recapitulated the LQT2 phenotype. In LQT3 iPS-CM, expressing NaV1.5-N406K, APs and [Ca2+]i transients were markedly prolonged. AP prolongation was sensitive to tetrodotoxin and to inhibiting Na+-Ca2+ exchange. These results suggest that LQTS mutations act partly on cytosolic Ca2+ cycling, potentially providing a basis for functionally targeted interventions regardless of the specific mutation site.

  18. Rapid and accurate measurement of the specific surface area of snow using infrared reflectance at 1310 and 1550 nm

    J.-C. Gallet

    2009-01-01

    Full Text Available Even though the specific surface area (SSA of snow is a crucial variable to determine the chemical and climatic impact of the snow cover, few data are available on snow SSA because current measurement methods are not simple to use in the field or do not have a sufficient accuracy. We propose here a novel determination method based on the measurement of the hemispherical reflectance of snow in the infrared using the DUFISSS instrument (DUal Frequency Integrating Sphere for Snow SSA measurement. DUFISSS uses 1310 and 1550 nm radiation provided by laser diodes, an integrating sphere 15 cm in diameter, and InGaAs photodiodes. For SSA<60 m2 kg−1, we use the 1310 nm radiation, reflectance is in the range 15 to 50% and the accuracy is 10%. For SSA>60 m2 kg−1, snow is usually of low to very low density (typically 30 to 100 kg m−3 and this produces artifacts caused by the e-folding length of light in snow being too long. We therefore use 1550 nm radiation for SSA>60 m2 kg−1. Reflectance is then in the range 5 to 12%, and the accuracy is 12%. No effect of crystal shape on reflectance was detected. We propose empirical equations to determine SSA from reflectance at both wavelengths, with that for 1310 nm taking into account the snow density. DUFISSS has been tested in the Alps to measure the snow area index (SAI of the Alpine snowpack in a south facing area at 2100 m elevation. This was done by measuring the SSA, thickness and density of the seven main layers of the snowpack in just 30 min, and a value of 5350 was found, significantly greater than in Arctic and subarctic regions. DUFISSS can now be used to help study issues related to polar and Alpine atmospheric chemistry and climate.

  19. Assessment of a sponge layer as a non-reflective boundary treatment with highly accurate gust–airfoil interaction results

    Crivellini, A.

    2016-02-01

    This paper deals with the numerical performance of a sponge layer as a non-reflective boundary condition. This technique is well known and widely adopted, but only recently have the reasons for a sponge failure been recognised, in analysis by Mani. For multidimensional problems, the ineffectiveness of the method is due to the self-reflections of the sponge occurring when it interacts with an oblique acoustic wave. Based on his theoretical investigations, Mani gives some useful guidelines for implementing effective sponge layers. However, in our opinion, some practical indications are still missing from the current literature. Here, an extensive numerical study of the performance of this technique is presented. Moreover, we analyse a reduced sponge implementation characterised by undamped partial differential equations for the velocity components. The main aim of this paper relies on the determination of the minimal width of the layer, as well as of the corresponding strength, required to obtain a reflection error of no more than a few per cent of that observed when solving the same problem on the same grid, but without employing the sponge layer term. For this purpose, a test case of computational aeroacoustics, the single airfoil gust response problem, has been addressed in several configurations. As a direct consequence of our investigation, we present a well documented and highly validated reference solution for the far-field acoustic intensity, a result that is not well established in the literature. Lastly, the proof of the accuracy of an algorithm for coupling sub-domains solved by the linear and non-liner Euler governing equations is given. This result is here exploited to adopt a linear-based sponge layer even in a non-linear computation.

  20. Is the pre-hospital ECG after out-of-hospital cardiac arrest accurate for the diagnosis of ST-elevation myocardial infarction?

    Salam, Idrees; Hassager, Christian; Thomsen, Jakob Hartvig;

    2016-01-01

    -hospital ROSC-ECG in predicting ST-elevation myocardial infarction (STEMI). METHOD: ROSC-ECGs of 145 comatose survivors of out-of-hospital cardiac arrest, randomly assigned in the Target Temperature Management trial, were classified according to the current STEMI ECG criteria (third universal definition of...... myocardial infarction). RESULTS: STEs were present in the pre-hospital ROSC-ECG of 78 (54%) patients. A final diagnosis revealed that 69 (48%) patients had STEMI, 31 (21%) patients had non-STEMI and 45 (31%) patients had no myocardial infarction. STE in ROSC-ECGs had a sensitivity of 74% (95% confidence...... intervention was successful in 68% versus 36% (P<0.001) of STE compared to no STE patients. No significant difference was found in 180-day mortality rates between STE and no STE patients (36% vs. 30%, Plogrank=0.37). CONCLUSION: The pre-hospital ROSC-ECG is a suboptimal diagnostic tool to predict STEMI and...

  1. Cardiac CT

    Dewey, Marc [Charite - Universitaetsmedizin Berlin (Germany). Inst. fuer Radiologie

    2011-07-01

    Computed tomography of the heart has become a highly accurate diagnostic modality that is attracting increasing attention. This extensively illustrated book aims to assist the reader in integrating cardiac CT into daily clinical practice, while also reviewing its current technical status and applications. Clear guidance is provided on the performance and interpretation of imaging using the latest technology, which offers greater coverage, better spatial resolution, and faster imaging. The specific features of scanners from all four main vendors, including those that have only recently become available, are presented. Among the wide range of applications and issues to be discussed are coronary artery bypass grafts, stents, plaques, and anomalies, cardiac valves, congenital and acquired heart disease, and radiation exposure. Upcoming clinical uses of cardiac CT, such as plaque imaging and functional assessment, are also explored. (orig.)

  2. Modest elevation in BNP in asymptomatic hypertensive patients reflects sub-clinical cardiac remodeling, inflammation and extracellular matrix changes.

    Phelan, Dermot

    2012-11-01

    In asymptomatic subjects B-type natriuretic peptide (BNP) is associated with adverse cardiovascular outcomes even at levels well below contemporary thresholds used for the diagnosis of heart failure. The mechanisms behind these observations are unclear. We examined the hypothesis that in an asymptomatic hypertensive population BNP would be associated with sub-clinical evidence of cardiac remodeling, inflammation and extracellular matrix (ECM) alterations. We performed transthoracic echocardiography and sampled coronary sinus (CS) and peripheral serum from patients with low (n = 14) and high BNP (n = 27). Peripheral BNP was closely associated with CS levels (r = 0.92, p<0.001). CS BNP correlated significantly with CS levels of markers of collagen type I and III turnover including: PINP (r = 0.44, p = 0.008), CITP (r = 0.35, p = 0.03) and PIIINP (r = 0.35, p = 0.001), and with CS levels of inflammatory cytokines including: TNF-α (r = 0.49, p = 0.002), IL-6 (r = 0.35, p = 0.04), and IL-8 (r = 0.54, p<0.001). The high BNP group had greater CS expression of fibro-inflammatory biomarkers including: CITP (3.8±0.7 versus 5.1±1.9, p = 0.007), TNF-α (3.2±0.5 versus 3.7±1.1, p = 003), IL-6 (1.9±1.3 versus 3.4±2.7, p = 0.02) and hsCRP (1.2±1.1 versus 2.4±1.1, p = 0.04), and greater left ventricular mass index (97±20 versus 118±26 g\\/m(2), p = 0.03) and left atrial volume index (18±2 versus 21±4, p = 0.008). Our data provide insight into the mechanisms behind the observed negative prognostic impact of modest elevations in BNP and suggest that in an asymptomatic hypertensive cohort a peripheral BNP measurement may be a useful marker of an early, sub-clinical pathological process characterized by cardiac remodeling, inflammation and ECM alterations.

  3. Modest elevation in BNP in asymptomatic hypertensive patients reflects sub-clinical cardiac remodeling, inflammation and extracellular matrix changes.

    Dermot Phelan

    Full Text Available In asymptomatic subjects B-type natriuretic peptide (BNP is associated with adverse cardiovascular outcomes even at levels well below contemporary thresholds used for the diagnosis of heart failure. The mechanisms behind these observations are unclear. We examined the hypothesis that in an asymptomatic hypertensive population BNP would be associated with sub-clinical evidence of cardiac remodeling, inflammation and extracellular matrix (ECM alterations. We performed transthoracic echocardiography and sampled coronary sinus (CS and peripheral serum from patients with low (n = 14 and high BNP (n = 27. Peripheral BNP was closely associated with CS levels (r = 0.92, p<0.001. CS BNP correlated significantly with CS levels of markers of collagen type I and III turnover including: PINP (r = 0.44, p = 0.008, CITP (r = 0.35, p = 0.03 and PIIINP (r = 0.35, p = 0.001, and with CS levels of inflammatory cytokines including: TNF-α (r = 0.49, p = 0.002, IL-6 (r = 0.35, p = 0.04, and IL-8 (r = 0.54, p<0.001. The high BNP group had greater CS expression of fibro-inflammatory biomarkers including: CITP (3.8±0.7 versus 5.1±1.9, p = 0.007, TNF-α (3.2±0.5 versus 3.7±1.1, p = 003, IL-6 (1.9±1.3 versus 3.4±2.7, p = 0.02 and hsCRP (1.2±1.1 versus 2.4±1.1, p = 0.04, and greater left ventricular mass index (97±20 versus 118±26 g/m(2, p = 0.03 and left atrial volume index (18±2 versus 21±4, p = 0.008. Our data provide insight into the mechanisms behind the observed negative prognostic impact of modest elevations in BNP and suggest that in an asymptomatic hypertensive cohort a peripheral BNP measurement may be a useful marker of an early, sub-clinical pathological process characterized by cardiac remodeling, inflammation and ECM alterations.

  4. Quantification of portal-bridging fibrosis area more accurately reflects fibrosis stage and liver stiffness than whole fibrosis or perisinusoidal fibrosis areas in chronic hepatitis C.

    Sandrini, Jérémy; Boursier, Jérôme; Chaigneau, Julien; Sturm, Nathalie; Zarski, Jean-Pierre; Le Bail, Brigitte; de Ledinghen, Victor; Calès, Paul; Rousselet, Marie-Christine

    2014-07-01

    early fibrosis stages but did not increase in septal or cirrhotic stages and that the portal-bridging fibrosis area appeared as a more accurate tool to assess fibrosis progression than the whole fibrosis area. PMID:24390214

  5. Cardiac fusion and complex congenital cardiac defects in thoracopagus twins: diagnostic value of cardiac CT

    Goo, Hyun Woo [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Park, Jeong-Jun [University of Ulsan College of Medicine, Asan Medical Center, Department of Pediatric Cardiac Surgery, Seoul (Korea, Republic of); Kim, Ellen Ai-Rhan [University of Ulsan College of Medicine, Asan Medical Center, Division of Neonatology, Department of Pediatrics, Seoul (Korea, Republic of); Won, Hye-Sung [University of Ulsan College of Medicine, Asan Medical Center, Department of Obstetrics and Gynecology, Seoul (Korea, Republic of)

    2014-09-15

    Most thoracopagus twins present with cardiac fusion and associated congenital cardiac defects, and assessment of this anatomy is of critical importance in determining patient care and outcome. Cardiac CT with electrocardiographic triggering provides an accurate and quick morphological assessment of both intracardiac and extracardiac structures in newborns, making it the best imaging modality to assess thoracopagus twins during the neonatal period. In this case report, we highlight the diagnostic value of cardiac CT in thoracopagus twins with an interatrial channel and complex congenital cardiac defects. (orig.)

  6. Cardiac tumors: optimal cardiac MR sequences and spectrum of imaging appearances.

    O'Donnell, David H

    2012-02-01

    OBJECTIVE: This article reviews the optimal cardiac MRI sequences for and the spectrum of imaging appearances of cardiac tumors. CONCLUSION: Recent technologic advances in cardiac MRI have resulted in the rapid acquisition of images of the heart with high spatial and temporal resolution and excellent myocardial tissue characterization. Cardiac MRI provides optimal assessment of the location, functional characteristics, and soft-tissue features of cardiac tumors, allowing accurate differentiation of benign and malignant lesions.

  7. An overview of cardiac morphogenesis.

    Schleich, Jean-Marc; Abdulla, Tariq; Summers, Ron; Houyel, Lucile

    2013-11-01

    Accurate knowledge of normal cardiac development is essential for properly understanding the morphogenesis of congenital cardiac malformations that represent the most common congenital anomaly in newborns. The heart is the first organ to function during embryonic development and is fully formed at 8 weeks of gestation. Recent studies stemming from molecular genetics have allowed specification of the role of cellular precursors in the field of heart development. In this article we review the different steps of heart development, focusing on the processes of alignment and septation. We also show, as often as possible, the links between abnormalities of cardiac development and the main congenital heart defects. The development of animal models has permitted the unraveling of many mechanisms that potentially lead to cardiac malformations. A next step towards a better knowledge of cardiac development could be multiscale cardiac modelling. PMID:24138816

  8. Structural and functional screening in human induced-pluripotent stem cell-derived cardiomyocytes accurately identifies cardiotoxicity of multiple drug types

    Doherty, Kimberly R., E-mail: kimberly.doherty@quintiles.com; Talbert, Dominique R.; Trusk, Patricia B.; Moran, Diarmuid M.; Shell, Scott A.; Bacus, Sarah

    2015-05-15

    Safety pharmacology studies that evaluate new drug entities for potential cardiac liability remain a critical component of drug development. Current studies have shown that in vitro tests utilizing human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CM) may be beneficial for preclinical risk evaluation. We recently demonstrated that an in vitro multi-parameter test panel assessing overall cardiac health and function could accurately reflect the associated clinical cardiotoxicity of 4 FDA-approved targeted oncology agents using hiPS-CM. The present studies expand upon this initial observation to assess whether this in vitro screen could detect cardiotoxicity across multiple drug classes with known clinical cardiac risks. Thus, 24 drugs were examined for their effect on both structural (viability, reactive oxygen species generation, lipid formation, troponin secretion) and functional (beating activity) endpoints in hiPS-CM. Using this screen, the cardiac-safe drugs showed no effects on any of the tests in our panel. However, 16 of 18 compounds with known clinical cardiac risk showed drug-induced changes in hiPS-CM by at least one method. Moreover, when taking into account the Cmax values, these 16 compounds could be further classified depending on whether the effects were structural, functional, or both. Overall, the most sensitive test assessed cardiac beating using the xCELLigence platform (88.9%) while the structural endpoints provided additional insight into the mechanism of cardiotoxicity for several drugs. These studies show that a multi-parameter approach examining both cardiac cell health and function in hiPS-CM provides a comprehensive and robust assessment that can aid in the determination of potential cardiac liability. - Highlights: • 24 drugs were tested for cardiac liability using an in vitro multi-parameter screen. • Changes in beating activity were the most sensitive in predicting cardiac risk. • Structural effects add in

  9. Structural and functional screening in human induced-pluripotent stem cell-derived cardiomyocytes accurately identifies cardiotoxicity of multiple drug types

    Safety pharmacology studies that evaluate new drug entities for potential cardiac liability remain a critical component of drug development. Current studies have shown that in vitro tests utilizing human induced pluripotent stem cell-derived cardiomyocytes (hiPS-CM) may be beneficial for preclinical risk evaluation. We recently demonstrated that an in vitro multi-parameter test panel assessing overall cardiac health and function could accurately reflect the associated clinical cardiotoxicity of 4 FDA-approved targeted oncology agents using hiPS-CM. The present studies expand upon this initial observation to assess whether this in vitro screen could detect cardiotoxicity across multiple drug classes with known clinical cardiac risks. Thus, 24 drugs were examined for their effect on both structural (viability, reactive oxygen species generation, lipid formation, troponin secretion) and functional (beating activity) endpoints in hiPS-CM. Using this screen, the cardiac-safe drugs showed no effects on any of the tests in our panel. However, 16 of 18 compounds with known clinical cardiac risk showed drug-induced changes in hiPS-CM by at least one method. Moreover, when taking into account the Cmax values, these 16 compounds could be further classified depending on whether the effects were structural, functional, or both. Overall, the most sensitive test assessed cardiac beating using the xCELLigence platform (88.9%) while the structural endpoints provided additional insight into the mechanism of cardiotoxicity for several drugs. These studies show that a multi-parameter approach examining both cardiac cell health and function in hiPS-CM provides a comprehensive and robust assessment that can aid in the determination of potential cardiac liability. - Highlights: • 24 drugs were tested for cardiac liability using an in vitro multi-parameter screen. • Changes in beating activity were the most sensitive in predicting cardiac risk. • Structural effects add in

  10. An overview of cardiac morphogenesis.

    Schleich, Jean-Marc; Abdulla, Tariq; Summers, Ron; Houyel, Lucile

    2013-01-01

    International audience Accurate knowledge of normal cardiac development is essential for properly understanding the morphogenesis of congenital cardiac malformations that represent the most common congenital anomaly in newborns. The heart is the first organ to function during embryonic development and is fully formed at 8 weeks of gestation. Recent studies stemming from molecular genetics have allowed specification of the role of cellular precursors in the field of heart development. In th...

  11. Atrial tumors in cardiac MRI

    Cardiac magnetic resonance imaging (MRI) is an important tool for the diagnosis of cardiac masses. Various cardiac tumors are predisposed to occurring in atrial structures. The aim of this review article is the description of atrial tumors and their morphological features in MRI. In general, cardiac tumors are rare: approximately 0.001-0.03% in autopsy studies. About 75% of them are benign. The most common cardiac tumor is the myxoma. They are predisposed to occur in the atria and show a characteristically strong hyperintense signal on T2-wieghted images in MRI. In other sequences a heterogeneous pattern reflects its variable histological appearance. Lipomas exhibit a signal behavior identical to fatty tissue with a typical passive movement in cine imaging. Fibroelastomas are the most common tumors of the cardiac valves. Consisting of avascular fibrous tissue, they often present with hypointense signal intensities. Thrombi attached to their surface can cause severe emboli even in small tumors. Amongst primary cardiac malignancies, sarcomas are most common and favor the atria. Secondary malignancies of the heart are far more common than primary ones (20-40 times). In case of known malignancies, approximately 10% of patients develop cardiac metastasis at the end of their disease. Lymphogenic metastases favor the pericardium, while hematogenic spread prefers the myocardium. Since they are not real atrial tumors, thrombi and anatomical structures of the atria have to be differentiated from other pathologies. (orig.)

  12. Methods in pharmacology: measurement of cardiac output

    Geerts, Bart F; Aarts, Leon P; Jansen, Jos R.

    2011-01-01

    Many methods of cardiac output measurement have been developed, but the number of methods useful for human pharmacological studies is limited. The ‘holy grail’ for the measurement of cardiac output would be a method that is accurate, precise, operator independent, fast responding, non-invasive, continuous, easy to use, cheap and safe. This method does not exist today. In this review on cardiac output methods used in pharmacology, the Fick principle, indicator dilution techniques, arterial pul...

  13. Cardiac rehabilitation

    ... attack or other heart problem. You might consider cardiac rehab if you have had: Heart attack Coronary heart disease (CHD) Heart failure Angina (chest pain) Heart or heart valve surgery Heart transplant Procedures such as angioplasty and stenting In some ...

  14. Cardiac Rehabilitation

    Cardiac rehabilitation (rehab) is a medically supervised program to help people who have A heart attack Angioplasty or coronary artery bypass grafting for coronary heart disease A heart valve repair or replacement A ...

  15. Cardiac sarcoidosis

    Costello BT; Nadel J.; Taylor AJ

    2016-01-01

    Benedict T Costello,1,2 James Nadel,3 Andrew J Taylor,1,21Department of Cardiovascular Medicine, The Alfred Hospital, 2Baker IDI Heart and Diabetes Research Institute, Melbourne, VIC, 3School of Medicine, University of Notre Dame, Sydney, NSW, Australia Abstract: Cardiac sarcoidosis is a rare but life-threatening condition, requiring a high degree of clinical suspicion and low threshold for investigation to make the diagnosis. The cardiac manifestations include heart failure, conducting syst...

  16. Pay attention to cardiac remodeling in cancer cachexia.

    Zheng, Yawen; Chen, Han; Li, Xiaoqing; Sun, Yuping

    2016-07-01

    Cancer cachexia is a complex and multifaceted disease state characterized by fatigue, weakness, and loss of skeletal muscle and adipose tissue. Recently, the profound negative effects of cancer cachexia on cardiac tissue draw much attention, which is likely to contribute to mortality in tumor-bearing animals. The mechanism of cardiac remodeling is not so clear and involved with a series of molecular alterations. In cancer cachexia model, progressive loss of left ventricular mass and decrease in myocardial function is observed and cardiac autonomic functions are altered. Levels of several emerging cardiovascular neurohormones are found elevating in patients with cancer, but it is still controversial whether the changes could reflect the heart injury accurately. The remedy for cardiac remodeling has been explored. It is showed that exercise can modulate signaling pathways activated by wasting cytokines and impact on the resulting outcomes on heart adaptation. Some drugs, such as bisoprolol, spironolactone, perindopril, tandospirone, and simvastatin, can mitigate adverse effects of the tumor on the heart and prolong survival. PMID:27108265

  17. Automated Segmentation of Cardiac Magnetic Resonance Images

    Stegmann, Mikkel Bille; Nilsson, Jens Chr.; Grønning, Bjørn A.

    2001-01-01

    Magnetic resonance imaging (MRI) has been shown to be an accurate and precise technique to assess cardiac volumes and function in a non-invasive manner and is generally considered to be the current gold-standard for cardiac imaging [1]. Measurement of ventricular volumes, muscle mass and function...

  18. Digital subtraction angiography in cardiac diseases

    DSA was done in 133 examinations of 128 patients during 2 years consist of 9 examination of IV DSA and 124 examination of selective cardiac DSA after cardiac catheterization. Open heart surgery was performed in 90 patients and 12 patients showed discrepancy between pre-and post operative diagnosis, showing a total 86.7% of diagnostic accuracy with DSA. We experienced the significant reduction in dose of contrast media, 30-40% of dose of conventional cardiac angiography. It is concluded that DSA is useful in the evaluation of septal defects, valvular disease and other congenital heart disease. DSA is an accurate simple and safe method in evaluating of cardiac diseases.

  19. Validation of measurements of Fourier phase and amplitude analysis of technetium99 gated cardiac scans using artificial hearts

    The use of artificial hearts, developed for total heart replacement programs, allows assessment of the accuracy of measuring the first Fourier component phase and amplitude when applied to gated cardiac technetium 99 scans. In the extreme example of asynchrony of ventricular contraction in coronary artery disease that of ventricular aneurysms, the first Fourier component measurements of amplitude were highly correlated to volume increases suggesting that the calculated amplitude accurately reflects volume changes. The calculated asynchrony using Fourier analysis of the gated technetium 99 studies of two artificial hearts was highly accurate when compared to the predetermined calculation of phase angle difference and hence degree of asynchrony. The studies suggest that measurement of phase and amplitude using the first Fourier component of time-activity waves of gated cardiac technetium 99 studies accurately measure degree of asynchrony and volume changes respectively

  20. Cardiac echinococcosis

    Ivanović-Krstić Branislava A.

    2002-01-01

    Full Text Available Cardiac hydatid disease is rare. We report on an uncommon hydatid cyst localized in the right ventricular wall, right atrial wall tricuspid valve left atrium and pericard. A 33-year-old woman was treated for cough, fever and chest pain. Cardiac echocardiograpic examination revealed a round tumor (5.8 x 4 cm in the right ventricular free wall and two smaller cysts behind that tumor. There were cysts in right atrial wall and tricuspidal valve as well. Serologic tests for hydatidosis were positive. Computed tomography finding was consistent with diagnosis of hydatid cyst in lungs and right hylar part. Surgical treatment was rejected due to great risk of cardiac perforation. Medical treatment with albendazole was unsuccessful and the patient died due to systemic hydatid involvement of the lungs, liver and central nervous system.

  1. Cardiac sarcoidosis

    Smedema, J.P.; Zondervan, P.E.; van Hagen, P.; ten Cate, F.J.; Bresser, P.; Doubell, A.F.; Pattynama, P.; Hoogsteden, H.C.; Balk, A.H.M.M.

    2002-01-01

    Sarcoidosis is a multi-system granulomatous disorder of unknown aetiology. Symptomatic cardiac involvement occurs in approximately 5% of patients. The prevalence of sarcoidosis in the Netherlands is unknown, but estimated to be approximately 20 per 100,000 population (3200 patients). We report on five patients who presented with different manifestations of cardiac sarcoidosis, and give a brief review on the current management of this condition. Magnetic Resonance Imaging (MRI) can be of great help in diagnosing this condition as well as in the follow-up of the response to therapy. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6 PMID:25696121

  2. Magnetic Resonance Imaging of Benign Cardiac Masses: A Pictorial Essay

    Thomas J Ward

    2013-01-01

    Full Text Available The differential diagnosis for a cardiac mass includes primary and metastatic neoplasms. While primary cardiac tumors are rare, metastatic disease to the heart is a common finding in cancer patients. Several "tumor-like" processes can mimic a true cardiac neoplasm with accurate diagnosis critical at guiding appropriate management. We present a pictorial essay of the most common benign cardiac masses and "mass-like" lesions with an emphasis on magnetic resonance imaging features.

  3. Reflecting Reflective Practice

    Galea, Simone

    2012-01-01

    This paper demystifies reflective practice on teaching by focusing on the idea of reflection itself and how it has been conceived by two philosophers, Plato and Irigaray. It argues that reflective practice has become a standardized method of defining the teacher in teacher education and teacher accreditation systems. It explores how practices of…

  4. Cardiac Pacemakers

    A complete survey of physiological biophysical,clinical and engineering aspects of cardiac facing,including the history and an assessment of possible future developments.Among the topics studied are: pacemakers, energy search, heart stimulating with pacemakers ,mathematical aspects of the electric cardio stimulation chronic, pacemaker implants,proceeding,treatment and control

  5. Reflecting reflection in supervision

    Lystbæk, Christian Tang

    Reflection has moved from the margins to the mainstream in supervision. Notions of reflection have become well established since the late 1980s. These notions have provided useful framing devices to help conceptualize some important processes in guidance and counseling. However, some applications...... previously associated with reflection and an exploration of alternative conceptions that view reflection within the context of settings which have a more group- and team-based orientation. Drawing on an action research project on health care supervision, the paper questions whether we should reject earlier...... views of reflection, rehabilitate them in order to capture broader connotations or move to new ways of regarding reflection that are more in keeping with not only reflective but also emotive, normative and formative views on supervision. The paper presents a critical perspective on supervision that...

  6. Reflecting on Cherenkov reflections

    Fargion, D.; Gaug, M.; Oliva, P.

    2007-01-01

    Magic Telescope may observe and reveal at horizons lights from air-shower Cherenkov reflections. The ground, the sea, the cloudy sky (below the mountain) may reflect PeVs-EeV UHECR Cherenkov lights observable by MAGIC telescopes. Even rarest UHE neutrino skimming the atmosphere or skimming the Earth may induce upward-horizontal airshowers: a new Neutrino Astronomy. These fluorescence signals or the Cherenkov reflections in upper cloudy sky may flash in correlated BL-Lac or GRB shining at oppo...

  7. Cardiac rhabdomyosarcoma

    Chlumský, Jaromír; Holá, Dana; Hlaváček, Karel; Michal, Michal; Švec, Alexander; Špatenka, Jaroslav; Dušek, Jan

    2001-01-01

    Cardiac sarcoma is a very rare neoplasm and is difficult to diagnose. The case of a 51-year-old man with a left atrial tumour, locally recurrent three months after its surgical removal, is presented. Computed tomography showed metastatic spread to the lung parenchyma. On revised histology, the mass extirpated was a sarcoma. Because of the metastatic spread, further therapy was symptomatic only; the patient died 15 months after the first manifestation of his problems. Immunohistochemical stain...

  8. Cardiac Calcification

    Morteza Joorabian

    2011-05-01

    Full Text Available There is a spectrum of different types of cardiac"ncalcifications with the importance and significance"nof each type of cardiac calcification, especially"ncoronary artery calcification. Radiologic detection of"ncalcifications within the heart is quite common. The"namount of coronary artery calcification correlates"nwith the severity of coronary artery disease (CAD."nCalcification of the aortic or mitral valve may indicate"nhemodynamically significant valvular stenosis."nMyocardial calcification is a sign of prior infarction,"nwhile pericardial calcification is strongly associated"nwith constrictive pericarditis. A spectrum of different"ntypes of cardiac calcifications (linear, annular,"ncurvilinear,... could be seen in chest radiography and"nother imaging modalities. So a carful inspection for"ndetection and reorganization of these calcifications"nshould be necessary. Numerous modalities exist for"nidentifying coronary calcification, including plain"nradiography, fluoroscopy, intravascular ultrasound,"nMRI, echocardiography, and conventional, helical and"nelectron-beam CT (EBCT. Coronary calcifications"ndetected on EBCT or helical CT can be quantifie,"nand a total calcification score (Cardiac Calcification"nScoring may be calculated. In an asymptomatic"npopulation and/or patients with concomitant risk"nfactors like diabetes mellitus, determination of the"npresence of coronary calcifications identifies the"npatients at risk for future myocardial infarction and"ncoronary artery disease. In patients without coronary"ncalcifications, future cardiovascular events could"nbe excluded. Therefore, detecting and recognizing"ncalcification related to the heart on chest radiography"nand other imaging modalities such as fluoroscopy, CT"nand echocardiography may have important clinical"nimplications.

  9. CT diagnosis of cardiac lipoma

    Objective: To investigate the application of CT in the diagnosis of cardiac lipoma. Methods: Retrospective analysis of 6 patients with cardiac lipoma confirmed by operation and pathology was done. Four patients had singles slice electron beam CT plain and contrast and movie scan. Two patients had 64-slice CT plain and enhanced scan. Results: (1) One patient was isolated intracavitary lipoma in the right artrium, 1 patient was isolated intrapericardial lipoma and 4 patients were intramural lipomas. Of the 4 intramural lipoma, 2 were infiltrative lipomas located in the left ventricle wall or the right ventricle and septum, 2 patients were isolated in the atrio-ventricular septum. (2) CT and three-dimensional reconstruction could depict the location, shape, size, margin and characteristic fat density of lipoma, indicating the diagnosis and classifications. The displacement of coronary artery, pulmonary inflammation and effusions of pericardium and pleural cavity could also be revealed. Conclusion: Cardiac lipoma can be accurately diagnosed and classified by CT. (authors)

  10. Cardiac conduction system

    The cardiac conduction system is a group of specialized cardiac muscle cells in the walls of the heart that send signals ... to contract. The main components of the cardiac conduction system are the SA node, AV node, bundle ...

  11. Unveiling nonischemic cardiomyopathies with cardiac magnetic resonance.

    Aggarwal, Niti R; Peterson, Tyler J; Young, Phillip M; Araoz, Philip A; Glockner, James; Mankad, Sunil V; Williamson, Eric E

    2014-02-01

    Cardiomyopathy is defined as a heterogeneous group of myocardial disorders with mechanical or electrical dysfunction. Identification of the etiology is important for accurate diagnosis, treatment and prognosis, but continues to be challenging. The ability of cardiac MRI to non-invasively obtain 3D-images of unparalleled resolution without radiation exposure and to provide tissue characterization gives it a distinct advantage over any other diagnostic tool used for evaluation of cardiomyopathies. Cardiac MRI can accurately visualize cardiac morphology and function and also help identify myocardial edema, infiltration and fibrosis. It has emerged as an important diagnostic and prognostic tool in tertiary care centers for work up of patients with non-ischemic cardiomyopathies. This review covers the role of cardiac MRI in evaluation of nonischemic cardiomyopathies, particularly in the context of other diagnostic and prognostic imaging modalities. PMID:24417294

  12. Cardiac MRI in Athletes

    Luijkx, T.

    2012-01-01

    Cardiac magnetic resonance imaging (CMR) is often used in athletes to image cardiac anatomy and function and is increasingly requested in the context of screening for pathology that can cause sudden cardiac death (SCD). In this thesis, patterns of cardiac adaptation to sports are investigated with C

  13. Reflective Teaching

    Farrell, Thomas S. C.

    2013-01-01

    Thomas Farrell's "Reflective Teaching" outlines four principles that take teachers from just doing reflection to making it a way of being. Using the four principles, Reflective Practice Is Evidence Based, Reflective Practice Involves Dialogue, Reflective Practice Links Beliefs and Practices, and Reflective Practice Is a Way of Life,…

  14. Accurate Finite Difference Algorithms

    Goodrich, John W.

    1996-01-01

    Two families of finite difference algorithms for computational aeroacoustics are presented and compared. All of the algorithms are single step explicit methods, they have the same order of accuracy in both space and time, with examples up to eleventh order, and they have multidimensional extensions. One of the algorithm families has spectral like high resolution. Propagation with high order and high resolution algorithms can produce accurate results after O(10(exp 6)) periods of propagation with eight grid points per wavelength.

  15. Cardiac MRI and CT features of inheritable and congenital conditions associated with sudden cardiac death

    Sparrow, Patrick; Merchant, Naeem; Provost, Yves; Doyle, Deirdre; Nguyen, Elsie; Paul, Narinder [University Health Network and Mount Sinai Hospital, Division of Cardiothoracic Imaging, Department of Medical Imaging, Toronto, Ontario (Canada)

    2009-02-15

    Cardiac MRI (CMR) and electrocardiogram (ECG)-gated multi-detector computed tomography (MDCT) are increasingly important tools in the identification and assessment of cardiac-related disease processes, including those associated with sudden cardiac death (SCD). While the commonest cause of SCD is coronary artery disease (CAD), in patients under 35 years inheritable cardiomyopathies such as hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy are important aetiologies. CMR in particular offers both accurate delineation of the morphological abnormalities associated with these and other conditions and the possibility for risk stratification for development of ventricular arrhythmias with demonstration of macroscopic scar by delayed enhancement imaging with intravenous gadolinium. (orig.)

  16. Cardiac perception and cardiac control. A review.

    Carroll, D

    1977-12-01

    The evidence regarding specific cardiac perception and discrimination, and its relationship to voluntary cardiac control, is critically reviewed. Studies are considered in three sections, depending on the method used to assess cardiac perception: questionnaire assessment, discrimination procedures, and heartbeat tracking. The heartbeat tracking procedure would appear to suffer least from interpretative difficulties. Recommendations are made regarding the style of analysis used to assess heartbeat perception in such tracking tasks. PMID:348240

  17. Reflection, Reflective Practice and Embodied Reflective Practice

    Leigh, Jennifer S; Bailey, Richard

    2013-01-01

    Although widely employed in professional practice of all kinds, ‘reflection’ and ‘reflective practice’ can be considered ‘success words’. That is, they elicit positive and supportive responses and yet the concepts are vague, ill-defined, contradictory and reflective skills can be hard to teach. Using examples from education and somatic movement therapy, we argue that a purely analytical approach to reflective practice that involves reflecting on thoughts alone is likely to lead into a negativ...

  18. Reflection Coefficients.

    Greenslade, Thomas B., Jr.

    1994-01-01

    Discusses and provides an example of reflectivity approximation to determine whether reflection will occur. Provides a method to show thin-film interference on a projection screen. Also applies the reflectivity concepts to electromagnetic wave systems. (MVL)

  19. What Is Cardiac Rehabilitation?

    ANSWERS by heart Treatments + Tests What Is Cardiac Rehabilitation? A cardiac rehabilitation (rehab) program takes place in a hospital or ... special help in making lifestyle changes. During your rehabilitation program you’ll… • Have a medical evaluation to ...

  20. A Rabbit Ventricular Action Potential Model Replicating Cardiac Dynamics at Rapid Heart Rates

    Mahajan, Aman; Shiferaw, Yohannes; Sato, Daisuke; Baher, Ali; Olcese, Riccardo; Xie, Lai-Hua; Yang, Ming-Jim; Chen, Peng-Sheng; Restrepo, Juan G.; Karma, Alain; Garfinkel, Alan; Qu, Zhilin; Weiss, James N.

    2008-01-01

    Mathematical modeling of the cardiac action potential has proven to be a powerful tool for illuminating various aspects of cardiac function, including cardiac arrhythmias. However, no currently available detailed action potential model accurately reproduces the dynamics of the cardiac action potential and intracellular calcium (Cai) cycling at rapid heart rates relevant to ventricular tachycardia and fibrillation. The aim of this study was to develop such a model. Using an existing rabbit ven...

  1. Effects of Aesthetic Chills on a Cardiac Signature of Emotionality.

    Maria Sumpf

    Full Text Available Previous studies have shown that a cardiac signature of emotionality (referred to as EK, which can be computed from the standard 12 lead electrocardiogram, ECG, predicts inter-individual differences in the tendency to experience and express positive emotion. Here, we investigated whether EK values can be transiently modulated during stimulation with participant-selected music pieces and film scenes that elicit strongly positive emotion.The phenomenon of aesthetic chills, as indicated by measurable piloerection on the forearm, was used to accurately locate moments of peak emotional responses during stimulation. From 58 healthy participants, continuous EK values, heart rate, and respiratory frequency were recorded during stimulation with film scenes and music pieces, and were related to the aesthetic chills. EK values, as well as heart rate, increased significantly during moments of peak positive emotion accompanied by piloerection.These results are the first to provide evidence for an influence of momentary psychological state on a cardiac signature of emotional personality (as reflected in EK values. The possibility to modulate ECG amplitude signatures via stimulation with emotionally significant music pieces and film scenes opens up new perspectives for the use of emotional peak experiences in the therapy of disorders characterized by flattened emotionality, such as depression or schizoid personality disorder.

  2. Diffuse infiltrative cardiac tuberculosis

    We present the cardiac magnetic resonance images of an unusual form of cardiac tuberculosis. Nodular masses in a sheet-like distribution were seen to infiltrate the outer myocardium and pericardium along most of the cardiac chambers. The lesions showed significant resolution on antitubercular therapy

  3. Cardiac tumours in children

    Parsons Jonathan M

    2007-03-01

    Full Text Available Abstract Cardiac tumours are benign or malignant neoplasms arising primarily in the inner lining, muscle layer, or the surrounding pericardium of the heart. They can be primary or metastatic. Primary cardiac tumours are rare in paediatric practice with a prevalence of 0.0017 to 0.28 in autopsy series. In contrast, the incidence of cardiac tumours during foetal life has been reported to be approximately 0.14%. The vast majority of primary cardiac tumours in children are benign, whilst approximately 10% are malignant. Secondary malignant tumours are 10–20 times more prevalent than primary malignant tumours. Rhabdomyoma is the most common cardiac tumour during foetal life and childhood. It accounts for more than 60% of all primary cardiac tumours. The frequency and type of cardiac tumours in adults differ from those in children with 75% being benign and 25% being malignant. Myxomas are the most common primary tumours in adults constituting 40% of benign tumours. Sarcomas make up 75% of malignant cardiac masses. Echocardiography, Computing Tomography (CT and Magnetic Resonance Imaging (MRI of the heart are the main non-invasive diagnostic tools. Cardiac catheterisation is seldom necessary. Tumour biopsy with histological assessment remains the gold standard for confirmation of the diagnosis. Surgical resection of primary cardiac tumours should be considered to relieve symptoms and mechanical obstruction to blood flow. The outcome of surgical resection in symptomatic, non-myxomatous benign cardiac tumours is favourable. Patients with primary cardiac malignancies may benefit from palliative surgery but this approach should not be recommended for patients with metastatic cardiac tumours. Surgery, chemotherapy and radiotherapy may prolong survival. The prognosis for malignant primary cardiac tumours is generally extremely poor.

  4. Diabetic cardiac autonomic dysfunction. Parasympathetic versus sympathetic

    Diabetic cardiac autonomic dysfunction often causes lethal arrhythmia and sudden cardiac death. 123I-Metaiodobenzylguanidine (MIBG) can evaluate cardiac sympathetic dysfunction, and analysis of heart rate variability (HRV) can reflect cardiac parasympathetic activity. We examined whether cardiac parasympathetic dysfunction assessed by HRV may correlate with sympathetic dysfunction assessed by MIBG in diabetic patients. In 24-hour electrocardiography, we analyzed 4 HRV parameters: high-frequency power (HF), HF in the early morning (EMHF), rMSSD and pNN50. MIBG planar images and SPECT were obtained 15 minutes (early) and 150 minutes (late) after injection and the heart washout rate was calculated. The defect score in 9 left ventricular regions was scored on a 4 point scale (0=normal - 3=severe defect). In 20 selected diabetic patients without congestive heart failure, coronary artery disease and renal failure, parasympathetic HRV parameters had a negative correlation with the sum of defect scores (DS) in the late images (R=-0.47 to -0.59, p<0.05) and some parameters had a negative correlation with the washout rate (R=-0.50 to -0.55, p<0.05). In a total of 64 diabetic patients also, these parameters had a negative correlation with late DS (R=-0.28 to -0.35, p<0.05) and early DS (R=-0.27 to -0.32, p<0.05). The progress of diabetic cardiac parasympathetic dysfunction may parallel the sympathetic one. (author)

  5. Stimulating endogenous cardiac regeneration

    Amanda eFinan

    2015-09-01

    Full Text Available The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration,a combination of these approaches couldameliorate the overall repair process to incorporate the participation ofmultiple cell players.

  6. Prognostic significance of late gadolinium enhancement quantification in cardiac magnetic resonance imaging of hypertrophic cardiomyopathy with systolic dysfunction.

    Funada, Akira; Kanzaki, Hideaki; Noguchi, Teruo; Morita, Yoshiaki; Sugano, Yasuo; Ohara, Takahiro; Hasegawa, Takuya; Hashimura, Hiromi; Ishibashi-Ueda, Hatsue; Kitakaze, Masafumi; Yasuda, Satoshi; Ogawa, Hisao; Anzai, Toshihisa

    2016-05-01

    Hypertrophic cardiomyopathy (HCM) with systolic dysfunction carries a poor prognosis. Although late gadolinium enhancement (LGE) on cardiac magnetic resonance is associated with adverse cardiac events in HCM and is inversely related to left ventricular ejection fraction (LVEF), it is unknown whether LGE or LVEF more accurately predicts adverse cardiac events in HCM with systolic dysfunction. We retrospectively assessed the extent of LGE with a threshold of 6 standard deviations in 46 consecutive HCM patients with systolic dysfunction defined as LVEF <50 % (average 35 ± 12 %) who underwent cardiac magnetic resonance (35 males, mean age 59 ± 14 years). They were followed up over 1755 ± 594 days. The composite adverse cardiac events end point included cardiovascular death, lethal arrhythmia, cardioembolic stroke, and unplanned heart failure hospitalization. LGE was detected in all patients, and the mean extent was 30 ± 15 %. Twenty-nine patients developed adverse cardiac events. Multivariate Cox proportional hazard analysis revealed the extent of LGE as a good independent predictor of adverse cardiac events. Risk increased with the extent of LGE (hazard ratio = 1.62/10 % increase in LGE, 95 % confidence interval = 1.23-2.15, p < 0.001). LVEF was inversely related to the extent of LGE (r = -0.44; p = 0.002) and was also an independent predictor of adverse cardiac events. Risk decreased with LVEF (hazard ratio = 0.68/10 % increase in LVEF, 95 % confidence interval = 0.51-0.91, p = 0.010). The Akaike information criterion evaluating the fit of a model demonstrated that the extent of LGE was a better independent predictor of MACE than LVEF (Akaike information criterion = 172.20 and 178.09, respectively).The extent of LGE was a good independent predictor of adverse cardiac events and reflected mortality and morbidity more precisely than LVEF in HCM with systolic dysfunction. PMID:25820658

  7. Preoperative cardiac risk management

    Vidaković Radosav; Poldermans Don; Nešković Aleksandar N.

    2011-01-01

    Approximately 100 million people undergo noncardiac surgery annually worldwide. It is estimated that around 3% of patients undergoing noncardiac surgery experience a major adverse cardiac event. Although cardiac events, like myocardial infarction, are major cause of perioperative morbidity or mortality, its true incidence is difficult to assess. The risk of perioperative cardiac complications depends mainly on two conditions: 1) identified risk factors, and 2) the type of the surgical p...

  8. Blunt cardiac rupture in patient with liver laceration

    王文林; 曾伟生; 蒋仁超

    2003-01-01

    The early diagnosis of cardiac rupture is one of the key factors for a successful outcome. However, the accurate diagnosis is often difficult in the early stage of injury, especially when some obvious severe wounds are found in other regions of the body,1,2 for they are easy to disguise the symptom of the heart. We report a case with cardiac rupture and liver trauma caused by traffic accident.

  9. Reflection groups

    In 2005, PISA organised proactive meetings of reflection groups on involvement in decision making, expert culture and ethical aspects of radiation protection.All reflection group meetings address particular targeted audiences while the output publication in book form is put forward

  10. Blunt cardiac rupture.

    Martin, T D; Flynn, T C; Rowlands, B J; Ward, R E; Fischer, R P

    1984-04-01

    Blunt injury to the heart ranges from contusion to disruption. This report comprises 14 patients seen during a 6-year period with cardiac rupture secondary to blunt trauma. Eight patients were injured in automobile accidents, two patients were injured in auto-pedestrian accidents, two were kicked in the chest by ungulates, and two sustained falls. Cardiac tamponade was suspected in ten patients. Five patients presented with prehospital cardiac arrest or arrested shortly after arrival. All underwent emergency department thoracotomy without survival. Two patients expired in the operating room during attempted cardiac repair; both had significant extracardiac injury. Seven patients survived, three had right atrial injuries, three had right ventricular injuries, and one had a left atrial injury. Cardiopulmonary bypass was not required for repair of the surviving patients. There were no significant complications from the cardiac repair. The history of significant force dispersed over a relatively small area of the precordium as in a kicking injury from an animal or steering wheel impact should alert the physician to possible cardiac rupture. Cardiac rupture should be considered in patients who present with signs of cardiac tamponade or persistent thoracic bleeding after blunt trauma. PMID:6708151

  11. Learning rules from multisource data for cardiac monitoring

    Cordier, Marie-Odile; Quiniou, René

    2009-01-01

    This paper formalises the concept of learning symbolic rules from multisource data in a cardiac monitoring context. Our sources, electrocardiograms and arterial blood pressure measures, describe cardiac behaviours from different viewpoints. To learn interpretable rules, we use an Inductive Logic Programming (ILP) method. We develop an original strategy to cope with the dimensionality issues caused by using this ILP technique on a rich multisource language. The results show that our method greatly improves the feasibility and the efficiency of the process while staying accurate. They also confirm the benefits of using multiple sources to improve the diagnosis of cardiac arrhythmias.

  12. Biomaterials for cardiac regeneration

    Ruel, Marc

    2015-01-01

    This book offers readers a comprehensive biomaterials-based approach to achieving clinically successful, functionally integrated vasculogenesis and myogenesis in the heart. Coverage is multidisciplinary, including the role of extracellular matrices in cardiac development, whole-heart tissue engineering, imaging the mechanisms and effects of biomaterial-based cardiac regeneration, and autologous bioengineered heart valves. Bringing current knowledge together into a single volume, this book provides a compendium to students and new researchers in the field and constitutes a platform to allow for future developments and collaborative approaches in biomaterials-based regenerative medicine, even beyond cardiac applications. This book also: Provides a valuable overview of the engineering of biomaterials for cardiac regeneration, including coverage of combined biomaterials and stem cells, as well as extracellular matrices Presents readers with multidisciplinary coverage of biomaterials for cardiac repair, including ...

  13. Mathematical cardiac electrophysiology

    Colli Franzone, Piero; Scacchi, Simone

    2014-01-01

    This book covers the main mathematical and numerical models in computational electrocardiology, ranging from microscopic membrane models of cardiac ionic channels to macroscopic bidomain, monodomain, eikonal models and cardiac source representations. These advanced multiscale and nonlinear models describe the cardiac bioelectrical activity from the cell level to the body surface and are employed in both the direct and inverse problems of electrocardiology. The book also covers advanced numerical techniques needed to efficiently carry out large-scale cardiac simulations, including time and space discretizations, decoupling and operator splitting techniques, parallel finite element solvers. These techniques are employed in 3D cardiac simulations illustrating the excitation mechanisms, the anisotropic effects on excitation and repolarization wavefronts, the morphology of electrograms in normal and pathological tissue and some reentry phenomena. The overall aim of the book is to present rigorously the mathematica...

  14. High Frequency QRS ECG Accurately Detects Cardiomyopathy

    Schlegel, Todd T.; Arenare, Brian; Poulin, Gregory; Moser, Daniel R.; Delgado, Reynolds

    2005-01-01

    RAZ scoring is a simple, accurate and inexpensive screening technique for cardiomyopathy. Although HF QRS ECG is highly sensitive for cardiomyopathy, its specificity may be compromised in patients with cardiac pathologies other than cardiomyopathy, such as uncomplicated coronary artery disease or multiple coronary disease risk factors. Further studies are required to determine whether HF QRS might be useful for monitoring cardiomyopathy severity or the efficacy of therapy in a longitudinal fashion.

  15. Quantifying Reflection

    Alcock, Gordon Lindsay

    2013-01-01

    This paper documents 1st semester student reflections on “learning to learn” in a team-based PBL environment with quantitative and qualitative student reflective feedback on the learning gains of 60 Architectural Technology and Construction Management students at VIA University College, Denmark. It...... contrasts the students’ self-assessment in a range of ‘product’ skills such as Revit, Structural Design, Mathematics of construction, Technical Installations; as well as ‘process’ competencies such as ‘Working in a team’, Sharing knowledge, Maintaining a portfolio and Reflecting ON learning and FOR learning...

  16. Imaging features of cardiac myxoma

    Objective: To study the imaging features of cardiac myxoma and their diagnostic values. Methods: Twenty-two patrents with cardiac myxoma were reviewed retrospectively for the clinical, pathologic, and radiologic findings. Posteroanterior and lateral chest radiographs, American Imatron C-150 XP Electron Beam CT examination, and Germany Siemens 1.5T Magnetom Vision MR scan were performed on every patient. Results: (1) Radiographs of 17 patients with left atrial myxoma showed evidence of mitral valve obstruction in 14(82.3%), radiographs of 5 patients with right atrial myxoma demonstrated right atrium enlargement in 3(60%) respectively. (2) CT scans of 22 myxomas demonstrated 18 (81.8%) lesions were hypoattenuated and 4 (19.1%) were isoattenuated relative to the myocardium. Calcification or ossification was seen in 3 patients. All myxomas apart from massive one were found attaching to the atrial septum. Movie mode could dis- play the movement of myxoma across the atrioventicular valves. (3) MRI studies of 22 myxomas showed 19 (86.3%) heterogeneous signal intensity and 3 (13.7%) homogeneous. They exhibited slight high or homogeneous signal intensity with both T1- and T2-weighted sequences, and low signal intensity with cine gradient recalled echo sequences. Point of attachment was visible in 21 (95.4%) cases. Conclusion: The typical radiograph sign of cardiac myxomas is mitral valve obstruction, CT and MR can demonstrate intracavitary lobular masses attacthing to artrial spetum. The latter two kinds of examinations not only provide accurate assessment of the size, location, and attachment point of these lesions, but also have important qualitative diagnostic advantage. (authors)

  17. [Cardiac evaluation before non-cardiac surgery].

    Menzenbach, Jan; Boehm, Olaf

    2016-07-01

    Before non-cardiac surgery, evaluation of cardiac function is no frequent part of surgical treatment. European societies of anesthesiology and cardiology published consensus-guidelines in 2014 to present a reasonable approach for preoperative evaluation. This paper intends to differentiate the composite of perioperative risk and to display the guidelines methodical approach to handle it. Features to identify patients at risk from an ageing population with comorbidities, are the classification of surgical risk, functional capacity and risk indices. Application of diagnostic means, should be used adjusted to this risk estimation. Cardiac biomarkers are useful to discover risk of complications or mortality, that cannot be assessed by clinical signs. After preoperative optimization and perioperative cardiac protection, the observation of the postoperative period remains, to prohibit complications or even death. In consideration of limited resources of intensive care department, postoperative ward rounds beyond intensive care units are considered to be an appropriate instrument to avoid or recognize complications early to reduce postoperative mortality. PMID:27479258

  18. The effect of classification of arrhythmic sudden cardiac death on the efficacy of cardiac resynchronization therapy in the CARE-HF study

    Uretsky, B.; Cleland, J.G.F.; Freemantle, N.; Daubert, J.C.; Erdmann, E.; Gras, D.; Tavazzi, L.; Thygesen, Kristian Anton

    2006-01-01

    Topic(s): The definition of arrhythmic sudden cardiac death (SCD) differs widely among studies, which will affect the frequency with which it is ascribed as the cause of death. Cardiac resynchronization therapy (CRT) was reported to reduce SCD in the CARE-HF study. This could reflect a real effec...

  19. Approaching system equilibrium with accurate or not accurate feedback information in a two-route system

    Zhao, Xiao-mei; Xie, Dong-fan; Li, Qi

    2015-02-01

    With the development of intelligent transport system, advanced information feedback strategies have been developed to reduce traffic congestion and enhance the capacity. However, previous strategies provide accurate information to travelers and our simulation results show that accurate information brings negative effects, especially in delay case. Because travelers prefer to the best condition route with accurate information, and delayed information cannot reflect current traffic condition but past. Then travelers make wrong routing decisions, causing the decrease of the capacity and the increase of oscillations and the system deviating from the equilibrium. To avoid the negative effect, bounded rationality is taken into account by introducing a boundedly rational threshold BR. When difference between two routes is less than the BR, routes have equal probability to be chosen. The bounded rationality is helpful to improve the efficiency in terms of capacity, oscillation and the gap deviating from the system equilibrium.

  20. Cardiac metabolism and arrhythmias

    Barth, Andreas S.; Tomaselli, Gordon F.

    2009-01-01

    Sudden cardiac death remains a leading cause of mortality in the Western world, accounting for up to 20% of all deaths in the U.S.1, 2 The major causes of sudden cardiac death in adults age 35 and older are coronary artery disease (70–80%) and dilated cardiomyopathy (10–15%).3 At the molecular level, a wide variety of mechanisms contribute to arrhythmias that cause sudden cardiac death, ranging from genetic predisposition (rare mutations and common polymorphisms in ion channels and structural...

  1. [Cardiac Rehabilitation 2015].

    Hoffmann, Andreas

    2015-11-25

    The goals of cardiac rehabilitation are (re-)conditioning and secondary prevention in patients with heart disease or an elevated cardiovascular risk profile. Rehabilitation is based on motivation through education, on adapted physical activity, instruction of relaxation techniques, psychological support and optimized medication. It is performed preferably in groups either in outpatient or inpatient settings. The Swiss working group on cardiac rehabilitation provides a network of institutions with regular quality auditing. Positive effects of rehabilitation programs on mortality and morbidity have been established by numerous studies. Although a majority of patients after cardiac surgery are being referred to rehabilitation, these services are notoriously underused after catheter procedures. PMID:26602848

  2. Comprehensive cardiac rehabilitation

    Kruse, Marie; Hochstrasser, Stefan; Zwisler, Ann-Dorthe O;

    2006-01-01

    OBJECTIVES: The costs of comprehensive cardiac rehabilitation are established and compared to the corresponding costs of usual care. The effect on health-related quality of life is analyzed. METHODS: An unprecedented and very detailed cost assessment was carried out, as no guidelines existed for...... uncertain and may be as high as euro 1.877. CONCLUSIONS: Comprehensive cardiac rehabilitation is more costly than usual care, and the higher costs are not outweighed by a quality of life gain. Comprehensive cardiac rehabilitation is, therefore, not cost-effective....

  3. Living cardiac tissue slices: an organotypic pseudo two-dimensional model for cardiac biophysics research.

    Wang, Ken; Terrar, Derek; Gavaghan, David J; Mu-U-Min, Razik; Kohl, Peter; Bollensdorff, Christian

    2014-08-01

    for up to 50 min. After release of sustained stretch, AP duration (APD) and CaT duration reverted to shorter values. Living cardiac tissue slices are a promising experimental model for the study of cardiac mechano-electric interactions. The methodology described here can be refined to achieve more accurate control over stretch amplitude and timing (e.g. using a computer-controlled motorised stage, or by synchronising electrical and mechanical events) and through monitoring of regional tissue deformation (e.g. by adding motion tracking). PMID:25124067

  4. Atrial tumors in cardiac MRI; Vorhoftumoren in der kardialen MRT

    Kraemer, Nils; Schoth, F.; Guenther, R.W.; Krombach, G. [Klinik fuer Radiologische Diagnostik, Universitaetsklinikum RWTH Aachen (Germany); Balzer, J.C.; Neizel, M.; Kuehl, H. [Klinik fuer Kardiologie, Pneumologie und Angiologie, Universitaetsklinikum RWTH Aachen (Germany)

    2009-11-15

    Cardiac magnetic resonance imaging (MRI) is an important tool for the diagnosis of cardiac masses. Various cardiac tumors are predisposed to occurring in atrial structures. The aim of this review article is the description of atrial tumors and their morphological features in MRI. In general, cardiac tumors are rare: approximately 0.001-0.03% in autopsy studies. About 75% of them are benign. The most common cardiac tumor is the myxoma. They are predisposed to occur in the atria and show a characteristically strong hyperintense signal on T2-wieghted images in MRI. In other sequences a heterogeneous pattern reflects its variable histological appearance. Lipomas exhibit a signal behavior identical to fatty tissue with a typical passive movement in cine imaging. Fibroelastomas are the most common tumors of the cardiac valves. Consisting of avascular fibrous tissue, they often present with hypointense signal intensities. Thrombi attached to their surface can cause severe emboli even in small tumors. Amongst primary cardiac malignancies, sarcomas are most common and favor the atria. Secondary malignancies of the heart are far more common than primary ones (20-40 times). In case of known malignancies, approximately 10% of patients develop cardiac metastasis at the end of their disease. Lymphogenic metastases favor the pericardium, while hematogenic spread prefers the myocardium. Since they are not real atrial tumors, thrombi and anatomical structures of the atria have to be differentiated from other pathologies. (orig.)

  5. Walking with Gianluca Di Bella during the development of clinical cardiac imaging

    2010-01-01

    Cardiac magnetic resonance imaging (MRI) for the diagnosis and management of many cardiac diseases has been established in clinical practice. It provides anatomic and functional information and is the most precise technique for quantification of ventricular volume, function and mass. Among cardiac MRI sequences used in clinical practice, delayed contrast enhancement is an accurate and reliable method used in the diagnosis of ischemic and nonischemic cardiomyopathies. In addition, new technolo...

  6. Multidetector row computed tomography may accurately estimate plaque vulnerability. Does MDCT accurately estimate plaque vulnerability? (Pro)

    Over the past decade, multidetector row computed tomography (MDCT) has become the most reliable and established of the noninvasive examination techniques for detecting coronary heart disease. Now MDCT is chasing intravascular ultrasound (IVUS) in terms of spatial resolution. Among the components of vulnerable plaque, MDCT may detect lipid-rich plaque, the lipid pool, and calcified spots using computed tomography number. Plaque components are detected by MDCT with high accuracy compared with IVUS and angioscopy when assessing vulnerable plaque. The TWINS study and TOGETHAR trial demonstrated that angioscopic loss of yellow color occurred independently of volumetric plaque change by statin therapy. These 2 studies showed that plaque stabilization and regression reflect independent processes mediated by different mechanisms and time course. Noncalcified plaque and/or low-density plaque was found to be the strongest predictor of cardiac events, regardless of lesion severity, and act as a potential marker of plaque vulnerability. MDCT may be an effective tool for early triage of patients with chest pain who have a normal electrocardiogram (ECG) and cardiac enzymes in the emergency department. MDCT has the potential ability to analyze coronary plaque quantitatively and qualitatively if some problems are resolved. MDCT may become an essential tool for detecting and preventing coronary artery disease in the future. (author)

  7. Multidetector row computed tomography may accurately estimate plaque vulnerability: does MDCT accurately estimate plaque vulnerability? (Pro).

    Komatsu, Sei; Imai, Atsuko; Kodama, Kazuhisa

    2011-01-01

    Over the past decade, multidetector row computed tomography (MDCT) has become the most reliable and established of the noninvasive examination techniques for detecting coronary heart disease. Now MDCT is chasing intravascular ultrasound (IVUS) in terms of spatial resolution. Among the components of vulnerable plaque, MDCT may detect lipid-rich plaque, the lipid pool, and calcified spots using computed tomography number. Plaque components are detected by MDCT with high accuracy compared with IVUS and angioscopy when assessing vulnerable plaque. The TWINS study and TOGETHAR trial demonstrated that angioscopic loss of yellow color occurred independently of volumetric plaque change by statin therapy. These 2 studies showed that plaque stabilization and regression reflect independent processes mediated by different mechanisms and time course. Noncalcified plaque and/or low-density plaque was found to be the strongest predictor of cardiac events, regardless of lesion severity, and act as a potential marker of plaque vulnerability. MDCT may be an effective tool for early triage of patients with chest pain who have a normal ECG and cardiac enzymes in the emergency department. MDCT has the potential ability to analyze coronary plaque quantitatively and qualitatively if some problems are resolved. MDCT may become an essential tool for detecting and preventing coronary artery disease in the future. PMID:21532180

  8. Molecular Basis of Cardiac Myxomas

    Pooja Singhal

    2014-01-01

    Full Text Available Cardiac tumors are rare, and of these, primary cardiac tumors are even rarer. Metastatic cardiac tumors are about 100 times more common than the primary tumors. About 90% of primary cardiac tumors are benign, and of these the most common are cardiac myxomas. Approximately 12% of primary cardiac tumors are completely asymptomatic while others present with one or more signs and symptoms of the classical triad of hemodynamic changes due to intracardiac obstruction, embolism and nonspecific constitutional symptoms. Echocardiography is highly sensitive and specific in detecting cardiac tumors. Other helpful investigations are chest X-rays, magnetic resonance imaging and computerized tomography scan. Surgical excision is the treatment of choice for primary cardiac tumors and is usually associated with a good prognosis. This review article will focus on the general features of benign cardiac tumors with an emphasis on cardiac myxomas and their molecular basis.

  9. Cardiac cachexia: hic et nunc

    Loncar, Goran; Springer, Jochen; Anker, Markus; Doehner, Wolfram

    2016-01-01

    Abstract Cardiac cachexia (CC) is the clinical entity at the end of the chronic natural course of heart failure (HF). Despite the efforts, even the most recent definition of cardiac cachexia has been challenged, more precisely, the addition of new criteria on top of obligatory weight loss. The pathophysiology of CC is complex and multifactorial. A better understanding of pathophysiological pathways in body wasting will contribute to establish potentially novel treatment strategies. The complex biochemical network related with CC and HF pathophysiology underlines that a single biomarker cannot reflect all of the features of the disease. Biomarkers that could pick up the changes in body composition before they convey into clinical manifestations of CC would be of great importance. The development of preventive and therapeutic strategies against cachexia, sarcopenia, and wasting disorders is perceived as an urgent need by healthcare professionals. The treatment of body wasting remains an unresolved challenge to this day. As CC is a multifactorial disorder, it is unlikely that any single agent will be completely effective in treating this condition. Among all investigated therapeutic strategies, aerobic exercise training in HF patients is the most proved to counteract skeletal muscle wasting and is recommended by treatment guidelines for HF. PMID:27386168

  10. Cardiac cachexia: hic et nunc.

    Loncar, Goran; Springer, Jochen; Anker, Markus; Doehner, Wolfram; Lainscak, Mitja

    2016-06-01

    Cardiac cachexia (CC) is the clinical entity at the end of the chronic natural course of heart failure (HF). Despite the efforts, even the most recent definition of cardiac cachexia has been challenged, more precisely, the addition of new criteria on top of obligatory weight loss. The pathophysiology of CC is complex and multifactorial. A better understanding of pathophysiological pathways in body wasting will contribute to establish potentially novel treatment strategies. The complex biochemical network related with CC and HF pathophysiology underlines that a single biomarker cannot reflect all of the features of the disease. Biomarkers that could pick up the changes in body composition before they convey into clinical manifestations of CC would be of great importance. The development of preventive and therapeutic strategies against cachexia, sarcopenia, and wasting disorders is perceived as an urgent need by healthcare professionals. The treatment of body wasting remains an unresolved challenge to this day. As CC is a multifactorial disorder, it is unlikely that any single agent will be completely effective in treating this condition. Among all investigated therapeutic strategies, aerobic exercise training in HF patients is the most proved to counteract skeletal muscle wasting and is recommended by treatment guidelines for HF. PMID:27386168

  11. Automatic Implantable Cardiac Defibrillator

    Full Text Available Automatic Implantable Cardiac Defibrillator February 19, 2009 Halifax Health Medical Center, Daytona Beach, FL Welcome to Halifax Health Daytona Beach, Florida. Over the next hour you' ...

  12. Sudden Cardiac Arrest

    ... scan, or MUGA, which shows how well your heart is pumping blood. Magnetic resonance imaging (MRI) which gives doctors detailed pictures of your heart. How is SCA treated? Sudden cardiac arrest should ...

  13. Sudden Cardiac Arrest

    ... Heart Risk Factors & Prevention Heart Diseases & Disorders Atrial Fibrillation (AFib) Sudden Cardiac Arrest (SCA) SCA: Who's At Risk? Prevention of SCA What Causes SCA? SCA Awareness Atrial Flutter Heart Block Heart Failure Sick Sinus Syndrome Substances & Heart Rhythm Disorders Symptoms & ...

  14. Sudden cardiac death

    Aranđelović Aleksandra Č.

    2004-01-01

    Full Text Available Sudden cardiac death in an athlete is rare and tragic event. An athlete's death draws high public attention given that athletes are considered the healthiest category of society. The vast majority of sudden cardiac death in young athletes is due to congenital cardiac malformations such as hypertrophie cardiomyopathy and various coronary artery anomalies. In athletes over age 35, the usual cause of sudden cardiac death is coronary artery disease. With each tragic death of a young athlete, there is a question why this tragedy has not been prevented. The American College of Sports Medicine and the American Heart Association recommend that a pre-participation exam should include a complete cardiovascular history and physical examination.

  15. Cardiac Risk Assessment

    ... to assess cardiac risk include: High-sensitivity C-reactive protein (hs-CRP) : Studies have shown that measuring ... LDL-C but does not respond to typical strategies to lower LDL-C such as diet, exercise, ...

  16. Cardiac arrest - cardiopulmonary resuscitation

    Basri Lenjani; Besnik Elshani; Nehat Baftiu; Kelmend Pallaska; Kadir Hyseni; Njazi Gashi; Nexhbedin Karemani; Ilaz Bunjaku; Taxhidin Zaimi; Arianit Jakupi

    2014-01-01

    Objective:To investigate application of cardiopulmonary resuscitation(CPR) measures within the golden minutes inEurope.Methods:The material was taken from theUniversityClinical Center ofKosovo -EmergencyCentre inPristina, during the two(2) year period(2010-2011).The collected date belong to the patients with cardiac arrest have been recorded in the patients' log book protocol at the emergency clinic.Results:During the2010 to2011 in the emergency center of theCUCK inPristina have been treated a total of269 patients with cardiac arrest, of whom159 or59.1% have been treated in2010, and110 patients or40.9% in2011.Of the269 patients treated in the emergency centre,93 or34.6% have exited lethally in the emergency centre, and176 or 65.4% have been transferred to other clinics.In the total number of patients with cardiac arrest, males have dominated with186 cases, or69.1%.The average age of patients included in the survey was56.7 year oldSD±16.0 years.Of the269 patients with cardiac arrest, defibrillation has been applied for93 or34.6% of patients.In the outpatient settings defibrillation has been applied for3 or3.2% of patients.Patients were defibrillated with application of one to four shocks. Of27 cases with who have survived cardiac arrest, none of them have suffered cardiac arrest at home,3 or11.1% of them have suffered cardiac arrest on the street, and24 or88.9% of them have suffered cardiac arrest in the hospital.5 out of27 patients survived have ended with neurological impairment.Cardiac arrest cases were present during all days of the week, but frequently most reported cases have been onMonday with32.0% of cases, and onFriday with24.5% of cases. Conclusions:All survivors from cardiac arrest have received appropriate medical assistance within10 min from attack, which implies that if cardiac arrest occurs near an institution health care(with an opportunity to provide the emergent health care) the rate of survival is higher.

  17. Awareness in cardiac anesthesia.

    Serfontein, Leon

    2010-02-01

    Cardiac surgery represents a sub-group of patients at significantly increased risk of intraoperative awareness. Relatively few recent publications have targeted the topic of awareness in this group. The aim of this review is to identify areas of awareness research that may equally be extrapolated to cardiac anesthesia in the attempt to increase understanding of the nature and significance of this scenario and how to reduce it.

  18. Safety in cardiac surgery

    Siregar, S.

    2013-01-01

    The monitoring of safety in cardiac surgery is a complex process, which involves many clinical, practical, methodological and statistical issues. The objective of this thesis was to measure and to compare safety in cardiac surgery in The Netherlands using the Netherlands Association for Cardio-Thoracic Surgery (NVT) database. The safety of care is usually measured using patient outcomes. If outcomes are not available, the process and structure of care may be used. Outcomes should be adjusted ...

  19. Cardiac rehabilitation in Germany.

    Karoff, Marthin; Held, Klaus; Bjarnason-Wehrens, Birna

    2007-02-01

    The purpose of this review is to give an overview of the rehabilitation measures provided for cardiac patients in Germany and to outline its legal basis and outcomes. In Germany the cardiac rehabilitation system is different from rehabilitation measures in other European countries. Cardiac rehabilitation in Germany since 1885 is based on specific laws and the regulations of insurance providers. Cardiac rehabilitation has predominantly been offered as an inpatient service, but has recently been complemented by outpatient services. A general agreement on the different indications for offering these two services has yet to be reached. Cardiac rehabilitation is mainly offered after an acute cardiac event and bypass surgery. It is also indicated in severe heart failure and special cases of percutaneous coronary intervention. Most patients are men (>65%) and the age at which events occur is increasing. The benefits obtained during the 3-4 weeks after an acute event, and confirmed in numerous studies, are often later lost under 'usual care' conditions. Many attempts have been made by rehabilitation institutions to improve this deficit by providing intensive aftercare. One instrument set up to achieve this is the nationwide institution currently comprising more than 6000 heart groups with approximately 120000 outpatients. After coronary artery bypass grafting or acute coronary syndrome cardiac rehabilitation can usually be started within 10 days. The multidisciplinary rehabilitation team consists of cardiologists, psychologists, exercise therapists, social workers, nutritionists and nurses. The positive effects of cardiac rehabilitation are also important economically, for example, for the improvement of secondary prevention and vocational integration. PMID:17301623

  20. Ranolazine in Cardiac Arrhythmia.

    Saad, Marwan; Mahmoud, Ahmed; Elgendy, Islam Y; Richard Conti, C

    2016-03-01

    Ranolazine utilization in the management of refractory angina has been established by multiple randomized clinical studies. However, there is growing evidence showing an evolving role in the field of cardiac arrhythmias. Multiple experimental and clinical studies have evaluated the role of ranolazine in prevention and management of atrial fibrillation, with ongoing studies on its role in ventricular arrhythmias. In this review, we will discuss the pharmacological, experimental, and clinical evidence behind ranolazine use in the management of various cardiac arrhythmias. PMID:26459200

  1. Cardiac tumours in infancy

    Yadava, O.P.

    2012-01-01

    Cardiac tumours in infancy are rare and are mostly benign with rhabdomyomas, fibromas and teratomas accounting for the majority. The presentation depends on size and location of the mass as they tend to cause cavity obstruction or arrhythmias. Most rhabdomyomas tend to regress spontaneously but fibromas and teratomas generally require surgical intervention for severe haemodynamic or arrhythmic complications. Other relatively rare cardiac tumours too are discussed along with an Indian perspect...

  2. Systems and methods for remote long standoff biometric identification using microwave cardiac signals

    McGrath, William R. (Inventor); Talukder, Ashit (Inventor)

    2012-01-01

    Systems and methods for remote, long standoff biometric identification using microwave cardiac signals are provided. In one embodiment, the invention relates to a method for remote biometric identification using microwave cardiac signals, the method including generating and directing first microwave energy in a direction of a person, receiving microwave energy reflected from the person, the reflected microwave energy indicative of cardiac characteristics of the person, segmenting a signal indicative of the reflected microwave energy into a waveform including a plurality of heart beats, identifying patterns in the microwave heart beats waveform, and identifying the person based on the identified patterns and a stored microwave heart beats waveform.

  3. Cardiac Image Registration

    2008-09-01

    Full Text Available Long procedure time and somewhat suboptimal results hinder the widespread use of catheter ablation of complex arrhythmias such as atrial fibrillation (AF. Due to lack of contrast differentiation between the area of interest and surrounding structures in a moving organ like heart, there is a lack of proper intraprocedural guidance using current imaging techniques for ablation. Cardiac image registration is currently under investigation and is in clinical use for AF ablation. Cardiac image registration, which involves integration of two images in the context of left atrium (LA, is intermodal, with the acquired image and the real-time reference image residing in different image spaces, and involves optimization, where one image space is transformed into the other. Unlike rigid body registration, cardiac image registration is unique and challenging due to cardiac motion during the cardiac cycle and due to respiration. This review addresses the basic principles of the emerging technique of registration and the inherent limitations as they relate to cardiac imaging and registration.

  4. Cardiac Image Registration

    Jasbir Sra

    2008-09-01

    Full Text Available Long procedure time and somewhat suboptimal results hinder the widespread use of catheter ablation of complex arrhythmias such as atrial fibrillation (AF. Due to lack of contrast differentiation between the area of interest and surrounding structures in a moving organ like heart, there is a lack of proper intraprocedural guidance using current imaging techniques for ablation. Cardiac image registration is currently under investigation and is in clinical use for AF ablation. Cardiac image registration, which involves integration of two images in the context of the left atrium (LA, is intermodal, with the acquired image and the real-time reference image residing in different image spaces, and involves optimization, where one image space is transformed into the other. Unlike rigid body registration, cardiac image registration is unique and challenging due to cardiac motion during the cardiac cycle and due to respiration. This review addresses the basic principles of the emerging technique of registration and the inherent limitations as they relate to cardiac imaging and registration.

  5. Reflective optics

    Korsch, Dietrich

    1991-01-01

    This is the first book dedicated exclusively to all-reflective imaging systems. It is a teaching tool as well as a practical design tool for anyone who specializes in optics, particularly for those interested in telescopes, infrared, and grazing-incidence systems. The first part of the book describes a unified geometric optical theory of all-reflective imaging systems (from near-normal to grazing incidence) developed from basic principles. The second part discusses correction methods and a multitude of closed-form solutions of well-corrected systems, supplemented with many conventional and unc

  6. Speckle Tracking Based Strain Analysis Is Sensitive for Early Detection of Pathological Cardiac Hypertrophy.

    Xiangbo An

    Full Text Available Cardiac hypertrophy is a key pathological process of many cardiac diseases. However, early detection of cardiac hypertrophy is difficult by the currently used non-invasive method and new approaches are in urgent need for efficient diagnosis of cardiac malfunction. Here we report that speckle tracking-based strain analysis is more sensitive than conventional echocardiography for early detection of pathological cardiac hypertrophy in the isoproterenol (ISO mouse model. Pathological hypertrophy was induced by a single subcutaneous injection of ISO. Physiological cardiac hypertrophy was established by daily treadmill exercise for six weeks. Strain analysis, including radial strain (RS, radial strain rate (RSR and longitudinal strain (LS, showed marked decrease as early as 3 days after ISO injection. Moreover, unlike the regional changes in cardiac infarction, strain analysis revealed global cardiac dysfunction that affects the entire heart in ISO-induced hypertrophy. In contrast, conventional echocardiography, only detected altered E/E', an index reflecting cardiac diastolic function, at 7 days after ISO injection. No change was detected on fractional shortening (FS, E/A and E'/A' at 3 days or 7 days after ISO injection. Interestingly, strain analysis revealed cardiac dysfunction only in ISO-induced pathological hypertrophy but not the physiological hypertrophy induced by exercise. Taken together, our study indicates that strain analysis offers a more sensitive approach for early detection of cardiac dysfunction than conventional echocardiography. Moreover, multiple strain readouts distinguish pathological cardiac hypertrophy from physiological hypertrophy.

  7. Postoperative cardiac arrest due to cardiac surgery complications

    To examine the role of anesthetists in the management of cardiac arrest occurring in association with cardiac anesthesia. In this retrospective study we studied the potential performances for each of the relevant incidents among 712 patients undergoing cardiac operations at Golestan and Naft Hospitals Ahwaz between November 2006 and July 2008. Out of total 712 patients undergoing cardiac surgery, cardiac arrest occurred in 28 cases (3.9%) due to different postoperative complications. This included massive bleeding (50% of cardiac arrest cases, 1.9% of patients); pulseless supra ventricular tachycardia (28.5% of cardiac arrest cases, 1.1% of patients); Heart Failure (7% of cardiac arrest cases, 0.2% of patients); Aorta Arc Rapture (3.5% of cardiac arrest cases, 0.1% of patients); Tamponade due to pericardial effusion (3.5% of cardiac arrest cases, 0.1% of total patients); Right Atrium Rupture (3.5% of cardiac arrest cases, 0.1% of patients) were detected after cardiac surgery. Out of 28 cases 7 deaths occurred (25% of cardiac arrest cases, 0.1% of patients). The most prevalent reason for cardiac arrest during post operative phase was massive bleeding (50%) followed by pulseless supra ventricular tachycardia (28.5%). Six patients had some morbidity and the remaining 15 patients recovered. There are often multiple contributing factors to a cardiac arrest under cardiac anesthesia, as much a complete systematic assessment of the patient, equipment, and drugs should be completed. We also found that the diagnosis and management of cardiac arrest in association with cardiac anesthesia differs considerably from that encountered elsewhere. (author)

  8. Cardiac MRI in ischemic heart disease

    Considerable progress has been made in cardiac magnetic resonance imaging (MRI). Cine MRI is recognized as the most accurate method for evaluating ventricular function. Late gadolinium-enhanced MRI can clearly delineate subendocardial infarction, and the assessment of transmural extent of infarction on MRI is widely useful for predicting myocardial viability. Stress myocardial perfusion MRI allows for detection of subendocardial myocardial ischemia, and the diagnostic accuracy of stress perfusion MRI is superior to stress perfusion single-photon emission computed tomography in patients with multivessel coronary artery disease (CAD). In recent years, image quality, volume coverage, acquisition speed and arterial contrast of 3-dimensional coronary magnetic resonance angiography (MRA) have been substantially improved with use of steady-state free precession sequences and parallel imaging techniques, permitting the acquisition of high-quality, whole-heart coronary MRA within a reasonably short imaging time. It is now widely recognized that cardiac MRI has tremendous potential for the evaluation of ischemic heart disease. However, cardiac MRI is technically complicated and its use in clinical practice is relatively limited. With further improvements in education and training, as well as standardization of appropriate study protocols, cardiac MRI will play a central role in managing patients with CAD. (author)

  9. Reconstruction of dynamic gated cardiac SPECT

    In this paper we propose an image reconstruction procedure which aims to unify gated single photon emission computed tomography (SPECT) and dynamic SPECT into a single method. We divide the cardiac cycle into a number of gate intervals as in gated SPECT, but treat the tracer distribution for each gate as a time-varying signal. By using both dynamic and motion-compensated temporal regularization, our reconstruction procedure will produce an image sequence that shows both cardiac motion and time-varying tracer distribution simultaneously. To demonstrate the proposed reconstruction method, we simulated gated cardiac perfusion imaging using the gated mathematical cardiac-torso (gMCAT) phantom with Tc99m-Teboroxime as the imaging agent. Our results show that the proposed method can produce more accurate reconstruction of gated dynamic images than independent reconstruction of individual gate frames with spatial smoothness alone. In particular, our results show that the former could improve the contrast to noise ratio of a simulated perfusion defect by as much as 100% when compared to the latter

  10. Chest pain of cardiac and noncardiac origin.

    Lenfant, Claude

    2010-10-01

    causes, gastroesophageal disorders are by far the most prevalent, especially gastroesophageal reflux disease. Fortunately, this disease can be diagnosed and treated effectively by proton-pump inhibitors. The other types of non-gastroesophageal reflux disease-related noncardiac chest pain are more difficult to diagnose and treat. In conclusion, the cause of chest pain must be accurately diagnosed; and treatment must be pursued according to the cause, especially if the cause is of cardiac origin. PMID:20837193

  11. Accurate calculation of thermal noise in multilayer coating

    Gurkovsky, Alexey; Vyatchanin, Sergey

    2010-01-01

    We derive accurate formulas for thermal fluctuations in multilayer interferometric coating taking into account light propagation inside the coating. In particular, we calculate the reflected wave phase as a function of small displacements of the boundaries between the layers using transmission line model for interferometric coating and derive formula for spectral density of reflected phase in accordance with Fluctuation-Dissipation Theorem. We apply the developed approach for calculation of t...

  12. Exercise-induced cardiac fatigue in low handicap polo horses

    CAO Bello

    2014-01-01

    Full Text Available Physical exercise leads to several changes in the cardiovascular system of horses and may induce abnormalities that are not observed at rest. Little is known about the cardiac effects of intense physical exercise performed by horses in polo competitions. This study aimed at identifying if exercise-induced cardiac fatigue is observed in healthy polo ponies. We examined 25 equine athletes before and after a training match. The results demonstrated post-exercise electrocardiographic alteration such as cardiac arrhythmia, QTc prolongation, abnormal T waves and ST-segment elevation. The post-exercise echocardiogram showed interventricular septum and left ventricle free wall thickness reduction, systolic volume decreased and ejection fraction decreased. These results suggest that polo causes exercise-induced cardiac fatigue. It was not possible to establish accurately the etiology of this abnormality, nor its long-term consequences.

  13. Towards accurate emergency response behavior

    Nuclear reactor operator emergency response behavior has persisted as a training problem through lack of information. The industry needs an accurate definition of operator behavior in adverse stress conditions, and training methods which will produce the desired behavior. Newly assembled information from fifty years of research into human behavior in both high and low stress provides a more accurate definition of appropriate operator response, and supports training methods which will produce the needed control room behavior. The research indicates that operator response in emergencies is divided into two modes, conditioned behavior and knowledge based behavior. Methods which assure accurate conditioned behavior, and provide for the recovery of knowledge based behavior, are described in detail

  14. Cardiac MRI of acute coronary syndrome.

    Akerem Khan, Shamruz; Khan, Shamruz Akarem; Williamson, Eric E; Foley, Thomas A; Cullen, Ethany L; Young, Phillip M; Araoz, Philip A

    2013-05-01

    Acute coronary syndrome (ACS) is a major cause of morbidity and mortality worldwide. New serological biomarkers, such as troponins, have improved the diagnosis of ACS; however, the diagnosis of ACS can still be difficult as there is marked heterogeneity in its presentation and significant overlap with other disorders presenting with chest pain. Evidence is accumulating that cardiac MRI provides information that can aid the detection and differential diagnosis of ACS, guide clinical decision-making and improve risk-stratification after an event. In this review, we present the relevant cardiac MRI techniques that can be used to detect ACS accurately, provide differential diagnosis, identify the sequelae of ACS, and determine prognostication after ACS. PMID:23668741

  15. MR tomography in cardiac septum defects

    Various flow phenomena can occur in MR tomography of the heart. In the present study the influence of various examination parameters on the imaging of flow phenomena behind cardiac septum defects was investigated by means of a model. In the examination by fast field echo sequence (FFE) the contrast between poststenotic jet and surrounding area was most pronounced if short echo times (TE 10 ms), a narrow flip angle (d=10 ) and layers of minor thickness (d=5 mm) had been selected. The number of acquisitions and the flow compensation exercised only slight influence on contrast. Our results point to the possibility of obtaining quantitative information on cardiac septum defects if the influence of examination parameters on the imaging of flow phenomena is accurately known. (orig.)

  16. Audible reflection density for different late reflection criteria in rooms

    Krueger, Donata; Jeong, Cheol-Ho; Brunskog, Jonas;

    2012-01-01

    For reasonably accurate but practical auralizations, some simplifications and approximations are needed. The main issue in the present investigation is that the reflection density of a room impulse response, in theory, increases so fast as a quadratic function of the elapsed time, even assuming...... only specular reflections. Therefore in this study, the upper threshold for audible reflection density is investigated for four different transition times of 25, 50, 75, and 100 ms through a headphone listening test. Binaural impulse responses and speech signals simulated in three rooms with different...... characteristics (an empty office, a lecture room, and an auditorium) are used as stimuli. Subjects are asked to increase/decrease the reflection density of a stimulus until they cannot distinguish it from the stimulus that follows the theoretical reflection density for the different transition times in the three...

  17. EANM/ESC guidelines for radionuclide imaging of cardiac function

    Hesse, B.; Lindhardt, T.B.; Acampa, W.; Anagnostopoulos, C.; Ballinger, J.; Bax, J.J.; Edenbrandt, L.; Flotats, A.; Germano, G.; Stopar, T.G.; Franken, P.; Kelion, A.; Kjaer, A.; Guludec, D. Le; Ljungberg, M.; Maenhout, A.F.; Marcassa, C.; Marving, J.; McKiddie, F.; Schaefer, W.M.; Stegger, L.; Underwood, R.

    2008-01-01

    Radionuclide imaging of cardiac function represents a number of well-validated techniques for accurate determination of right (RV) and left ventricular (LV) ejection fraction (EF) and LV volumes. These first European guidelines give recommendations for how and when to use first-pass and equilibri...

  18. Pediatric cardiac postoperative care

    Auler Jr. José Otávio Costa

    2002-01-01

    Full Text Available The Heart Institute of the University of São Paulo, Medical School is a referral center for the treatment of congenital heart diseases of neonates and infants. In the recent years, the excellent surgical results obtained in our institution may be in part due to modern anesthetic care and to postoperative care based on well-structured protocols. The purpose of this article is to review unique aspects of neonate cardiovascular physiology, the impact of extracorporeal circulation on postoperative evolution, and the prescription for pharmacological support of acute cardiac dysfunction based on our cardiac unit protocols. The main causes of low cardiac output after surgical correction of heart congenital disease are reviewed, and methods of treatment and support are proposed as derived from the relevant literature and our protocols.

  19. Accurate determination of antenna directivity

    Dich, Mikael

    1997-01-01

    The derivation of a formula for accurate estimation of the total radiated power from a transmitting antenna for which the radiated power density is known in a finite number of points on the far-field sphere is presented. The main application of the formula is determination of directivity from power...

  20. Evaluation of respiratory and cardiac motion correction schemes in dual gated PET/CT cardiac imaging

    Lamare, F., E-mail: frederic.lamare@chu-bordeaux.fr; Fernandez, P. [Univ. Bordeaux, INCIA, UMR 5287, F-33400 Talence (France); CNRS, INCIA, UMR 5287, F-33400 Talence (France); Service de Médecine Nucléaire, Hôpital Pellegrin, CHU de Bordeaux, 33076 Bordeaux (France); Le Maitre, A.; Visvikis, D. [INSERM, UMR1101, LaTIM, Université de Bretagne Occidentale, 29609 Brest (France); Dawood, M.; Schäfers, K. P. [European Institute for Molecular Imaging, University of Münster, Mendelstr. 11, 48149 Münster (Germany); Rimoldi, O. E. [Vita-Salute University and Scientific Institute San Raffaele, Milan, Italy and CNR Istituto di Bioimmagini e Fisiologia Molecolare, Milan (Italy)

    2014-07-15

    observed in the performance of the two motion models considered. Superior image SNR and contrast were seen using the affine respiratory motion model in combination with the diastole cardiac bin in comparison to the use of the whole cardiac cycle. In contrast, when simultaneously correcting for cardiac beating and respiration, the elastic respiratory motion model outperformed the affine model. In this context, four cardiac bins associated with eight respiratory amplitude bins seemed to be adequate. Conclusions: Considering the compensation of respiratory motion effects only, both affine and elastic based approaches led to an accurate resizing and positioning of the myocardium. The use of the diastolic phase combined with an affine model based respiratory motion correction may therefore be a simple approach leading to significant quality improvements in cardiac PET imaging. However, the best performance was obtained with the combined correction for both cardiac and respiratory movements considering all the dual-gated bins independently through the use of an elastic model based motion compensation.

  1. Evaluation of respiratory and cardiac motion correction schemes in dual gated PET/CT cardiac imaging

    observed in the performance of the two motion models considered. Superior image SNR and contrast were seen using the affine respiratory motion model in combination with the diastole cardiac bin in comparison to the use of the whole cardiac cycle. In contrast, when simultaneously correcting for cardiac beating and respiration, the elastic respiratory motion model outperformed the affine model. In this context, four cardiac bins associated with eight respiratory amplitude bins seemed to be adequate. Conclusions: Considering the compensation of respiratory motion effects only, both affine and elastic based approaches led to an accurate resizing and positioning of the myocardium. The use of the diastolic phase combined with an affine model based respiratory motion correction may therefore be a simple approach leading to significant quality improvements in cardiac PET imaging. However, the best performance was obtained with the combined correction for both cardiac and respiratory movements considering all the dual-gated bins independently through the use of an elastic model based motion compensation

  2. Giant Cardiac Cavernous Hemangioma.

    Unger, Eric; Costic, Joseph; Laub, Glenn

    2015-07-01

    We report the case of an asymptomatic giant cardiac cavernous hemangioma in a 71-year-old man. The intracardiac mass was discovered incidentally during surveillance for his prostate cancer; however, the patient initially declined intervention. On presentation to our institution 7 years later, the lesion had enlarged significantly, and the patient consented to excision. At surgery, an 8 × 6.5 × 4.8 cm intracardiac mass located on the inferior heart border was excised with an intact capsule through a median sternotomy approach. The patient had an uneventful postoperative course. We discuss the diagnostic workup, treatment, and characteristics of this rare cardiac tumor. PMID:26140782

  3. Left and right ventricle assessment with Cardiac CT: validation study vs. Cardiac MR

    Maffei, Erica; Seitun, Sara [Giovanni XXIII Hospital, Cardiovascular Radiology Unit, Monastier di Treviso (Italy); Messalli, Giancarlo; Catalano, Onofrio [SDN Foundation - IRCCS, Naples (Italy); Martini, Chiara; Cademartiri, Filippo [Giovanni XXIII Hospital, Cardiovascular Radiology Unit, Monastier di Treviso (Italy); Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Nieman, Koen; Rossi, Alexia; Mollet, Nico R. [Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Guaricci, Andrea I. [Azienda Ospedaliero-Universitaria di Foggia, Department of Cardiology, Foggia (Italy); Tedeschi, Carlo [Ospedale San Gennaro, Department of Cardiology, Naples (Italy)

    2012-05-15

    To compare Magnetic Resonance (MR) and Computed Tomography (CT) for the assessment of left (LV) and right (RV) ventricular functional parameters. Seventy nine patients underwent both Cardiac CT and Cardiac MR. Images were acquired using short axis (SAX) reconstructions for CT and 2D cine b-SSFP (balanced-steady state free precession) SAX sequence for MR, and evaluated using dedicated software. CT and MR images showed good agreement: LV EF (Ejection Fraction) (52 {+-} 14% for CT vs. 52 {+-} 14% for MR; r = 0.73; p > 0.05); RV EF (47 {+-} 12% for CT vs. 47 {+-} 12% for MR; r = 0.74; p > 0.05); LV EDV (End Diastolic Volume) (74 {+-} 21 ml/m{sup 2} for CT vs. 76 {+-} 25 ml/m{sup 2} for MR; r = 0.59; p > 0.05); RV EDV (84 {+-} 25 ml/m{sup 2} for CT vs. 80 {+-} 23 ml/m{sup 2} for MR; r = 0.58; p > 0.05); LV ESV (End Systolic Volume)(37 {+-} 19 ml/m{sup 2} for CT vs. 38 {+-} 23 ml/m{sup 2} for MR; r = 0.76; p > 0.05); RV ESV (46 {+-} 21 ml/m{sup 2} for CT vs. 43 {+-} 18 ml/m{sup 2} for MR; r = 0.70; p > 0.05). Intra- and inter-observer variability were good, and the performance of CT was maintained for different EF subgroups. Cardiac CT provides accurate and reproducible LV and RV volume parameters compared with MR, and can be considered as a reliable alternative for patients who are not suitable to undergo MR. circle Cardiac-CT is able to provide Left and Right Ventricular function. circle Cardiac-CT is accurate as MR for LV and RV volume assessment. (orig.)

  4. Radiography in cardiology [cardiac disorders, cardiac insufficiency

    The diagnostic procedure in cardiology nearly always requires an X-ray examination of the thorax. This examination is very informative when it is correctly performed and interpreted. The radiographs need to be read precisely and comprehensively: this includes the evaluation of the silhouette of the heart (size, form and position) as well as the examination of extra-cardiac thoracic structures allowing among other things to search for signs of cardiac insufficiency. The conclusion of the X-ray examination can be drawn after having brought together information concerning the case history, the clinical examination and the study of the radiographs. The radiologist finds himself in one of three situations: (1) the information provided by the X-ray pictures is characteristic of a disease and permits a diagnosis, (2) the X-ray pictures indicate a group of hypotheses; further complementary tests could be useful and (3) the X-ray pictures provide ambiguous even contradictory information; it is necessary to complete the radiological examination by other techniques such as an ultrasonographic study of the heart

  5. Serum myoglobin after cardiac catheterisation.

    McComb, J. M.; McMaster, E A

    1982-01-01

    Study of 80 consecutive patients undergoing elective diagnostic cardiac catheterisation showed that after the procedure 25 (31%) developed myoglobinaemia. This was attributed to complications of the catheterisation in two. The remaining 23 had received premedication by intramuscular injection. In patients without intramuscular injections myoglobinaemia did not occur after uncomplicated cardiac catheterisation. The study did not support the proposition that cardiac catheterisation results in m...

  6. Accurate radiative transfer calculations for layered media.

    Selden, Adrian C

    2016-07-01

    Simple yet accurate results for radiative transfer in layered media with discontinuous refractive index are obtained by the method of K-integrals. These are certain weighted integrals applied to the angular intensity distribution at the refracting boundaries. The radiative intensity is expressed as the sum of the asymptotic angular intensity distribution valid in the depth of the scattering medium and a transient term valid near the boundary. Integrated boundary equations are obtained, yielding simple linear equations for the intensity coefficients, enabling the angular emission intensity and the diffuse reflectance (albedo) and transmittance of the scattering layer to be calculated without solving the radiative transfer equation directly. Examples are given of half-space, slab, interface, and double-layer calculations, and extensions to multilayer systems are indicated. The K-integral method is orders of magnitude more accurate than diffusion theory and can be applied to layered scattering media with a wide range of scattering albedos, with potential applications to biomedical and ocean optics. PMID:27409700

  7. Hepato-cardiac disorders

    Yasser; Mahrous; Fouad; Reem; Yehia

    2014-01-01

    Understanding the mutual relationship between the liver and the heart is important for both hepatologists and cardiologists. Hepato-cardiac diseases can be classified into heart diseases affecting the liver, liver diseases affecting the heart, and conditions affecting the heart and the liver at the same time. Differential diagnoses of liver injury are extremely important in a cardiologist’s clinical practice calling for collaboration between cardiologists and hepatologists due to the many other diseases that can affect the liver and mimic haemodynamic injury. Acute and chronic heart failure may lead to acute ischemic hepatitis or chronic congestive hepatopathy. Treatment in these cases should be directed to the primary heart disease. In patients with advanced liver disease, cirrhotic cardiomyopathy may develop including hemodynamic changes, diastolic and systolic dysfunctions, reduced cardiac performance and electrophysiological abnormalities. Cardiac evaluation is important for patients with liver diseases especially before and after liver transplantation. Liver transplantation may lead to the improvement of all cardiac changes and the reversal of cirrhotic cardiomyopathy. There are systemic diseases that may affect both the liver and the heart concomitantly including congenital, metabolic and inflammatory diseases as well as alcoholism. This review highlights these hepatocardiac diseases

  8. Primary cardiac tumors

    Cardiac tumors happen to be among the less known pathologies without clear treatment standards. Even one decade ago most of the cardiac tumor diagnosis were made post mortem, and only reports of isolated cases could be found in the literature, showing the lack of interest in the investigation of these pathologies by cardiology and cardiovascular surgery specialists. With the development of echocardiography and of cardiovascular surgery, more cases of primary and metastatic cardiac tumors have been diagnosed. Many cases have been treated by palliative or curative surgical interventions, thus increasing the reports in the world literature and the experience in this field, and pointing out the real incidence of these pathologies, not being as bizarre as it had been considered. a revision of the literature will be made, in which the frequency and the suggested interventions will be reported, as well as the cases of cardiac pathology in two cardiovascular centers of the country known by the author. The echocardiographic, pathologic and histological characteristics of the representative cases will be presented, without a greater evidence level, due to the problem's incidence and the few cases reported by these centers

  9. Automatic Implantable Cardiac Defibrillator

    Full Text Available ... Over the next hour you'll see the implantation of an automated implantable cardiac defibrillator. The surgery ... evening we're going to be discussing the implantation of a defibrillator. It’s a battery-powered implantable ...

  10. Cardiac effects of vasopressin.

    Pelletier, Jean-Sébastien; Dicken, Bryan; Bigam, David; Cheung, Po-Yin

    2014-07-01

    Vasopressin is an essential hormone involved in the maintenance of cardiovascular homeostasis. It has been in use therapeutically for many decades, with an emphasis on its vasoconstrictive and antidiuretic properties. However, this hormone has a ubiquitous influence and has specific effects on the heart. Although difficult to separate from its powerful vascular effects in the clinical setting, a better understanding of vasopressin's direct cardiac effects could lead to its more effective clinical use for a variety of shock states by maximizing its therapeutic benefit. The cardiac-specific effects of vasopressin are complex and require further elucidation. Complicating our understanding include the various receptors and secondary messengers involved in vasopressin's effects, which may lead to various results based on differing doses and varying environmental conditions. Thus, there have been contradictory reports on vasopressin's action on the coronary vasculature and on its effect on inotropy. However, beneficial results have been found and warrant further study to expand the potential therapeutic role of vasopressin. This review outlines the effect of vasopressin on the coronary vasculature, cardiac contractility, and on hypertrophy and cardioprotection. These cardiac-specific effects of vasopressin represent an interesting area for further study for potentially important therapeutic benefits. PMID:24621650

  11. Cardiac pacemaker power sources

    A review of chemical and radioisotope batteries used in cardiac pacemakers is presented. The battery systems are examined in terms of longevity, reliability, cost, size and shape, energy density, weight, internal resistance versus time, end-of-life voltage, chemical compatibility, and potential failure mechanisms

  12. Inspiring Reflections

    Muchie, Mammo

    2011-01-01

    life is not free from fluctuations, cycles, disruptions, crises and destructions both human and ecological. Innovation research ought to position itself to address environmental, financial and economic crises. The third is innovation research for development by addressing not only poverty erdaication......A numberof Chris Freeman's colleagues were asked to reflect on what they thought describes his life and work in a few words. Some of the colleagues replied including former SPRU students that were taught or supervised by Chris Freeman. Their views on what they thought were Chris Freeman's defining...... contributions have been put together. There are a number of ways to continue Chris Freeman's legacy on innovation research. The first is to build in a critical tradition in the economics of innovation research by introducing fearlessly emancipatory epistemology. Second the economic system that dominates social...

  13. [Cardiac amyloidosis. General review].

    Laraki, R

    1994-04-01

    Cardiac amyloidosis, most often of AL type, is a non-exceptional disease as it represents 5 to 10% of non-ischemic cardiomyopathies. It realizes typically a restrictive cardiomyopathy. Nevertheless the wide diversity of possible presentation makes it a "big shammer" which must be evoked in front of every unexplained cardiopathy after the age of forty. If some associated manifestations can rapidly suggest the diagnosis, as a peripheric neuropathy especially a carpal tunnel syndrome or palpebral ecchymosis, cardiac involvement can also evolve in an apparently isolated way. The most suggestive paraclinic elements for the diagnosis are, in one hand, the increased myocardial echogenicity with a "granular sparkling" appearance seen throughout all walls of the left ventricle and, in the other hand, the association of a thickened left ventricle and a low voltage (electrocardiogram could also show pseudo-infarct Q waves). In front of such aspects, the proof of amyloidosis is brought by an extra-cardiac biopsy or by scintigraphy with labelled serum amyloid P component, so that the indications of endomyocardial biopsy are very limited today. The identification of the amyloid nature of a cardiopathy has an direct therapeutic implication: it contra-indicates the use of digitalis, calcium channel blockers and beta-blockers. The treatment of AL amyloidosis (chemotherapy with alkylant agents) remains very unsatisfactory especially in the cardiac involvement which is the most frequent cause of death (in AL amyloidosis). Last, cardiac amyloidosis is a bad indication for transplantation which results are burden by rapid progression of deposits especially in the gastro-intestinal tract and the nervous system. PMID:8059146

  14. Cardiac surgery outcomes.

    Halpin, Linda S; Barnett, Scott D; Beachy, Jim

    2003-01-01

    Accrediting organizations and payers are demanding valid and reliable data that demonstrate the value of services. Federal agencies, healthcare industry groups, and healthcare watchdog groups are increasing the demand for public access to outcomes data. A new and growing outcomes dynamic is the information requested by prospective patients in an increasingly consumer-oriented business. Patients demand outcomes, and resources are developing to meet these demands. Physicians are increasingly confronted with requests for information about their mortality and morbidity rates, malpractice suits, and disciplinary actions received. For example, in Virginia, prospective patients have access to data provided by the nonprofit group Virginia Health Information. After numerous resolutions by the Virginia Senate since 1999, the prospective Virginia medical consumer now has access to several annual publications: Virginia Hospitals: A Consumer's Guide, 1999 Annual Report and Strategic Plan Update, and the 1999 Industry Report: Virginia Hospitals and Nursing Facilities. Consumers have access to cardiac outcomes data stratified by hospital, gender, and cardiac service line (cardiac surgery, noninvasive cardiology, and invasive cardiology). This is particularly relevant to IHI because Virginia Health Information specifically targets cardiac care. IHI has a sizable investment in cardiovascular outcomes and has found outcomes measurement and research are key to providing quality care. IHI's goal is to move from an outcomes management model to a disease management model. The hope is to incorporate all aspects of the patient's continuum of care, from preoperative and diagnostic services through cardiac interventions to postoperative rehabilitation. Furthermore, every step along the way will be supported with functional status and quality of life assessments. Although these goals are ambitious and expensive, the return on investment is high. PMID:14618772

  15. Risk factors and the effect of cardiac resynchronization therapy on cardiac and non-cardiac mortality in MADIT-CRT

    Perkiomaki, Juha S; Ruwald, Anne-Christine; Kutyifa, Valentina;

    2015-01-01

    causes, 108 (63.9%) deemed cardiac, and 61 (36.1%) non-cardiac. In multivariate analysis, increased baseline creatinine was significantly associated with both cardiac and non-cardiac deaths [hazard ratio (HR) 2.97, P ...AIMS: To understand modes of death and factors associated with the risk for cardiac and non-cardiac deaths in patients with cardiac resynchronization therapy with implantable cardioverter-defibrillator (CRT-D) vs. implantable cardioverter-defibrillator (ICD) therapy, which may help clarify...

  16. Preoperative cardiac computed tomography for demonstration of congenital cardiac septal defect in adults

    We aimed to evaluate the role of preoperative cardiac computed tomography (CT) for adults with congenital cardiac septal defect (CSD). Sixty-five consecutive patients who underwent preoperative CT and surgery for CSD were included. The diagnostic accuracy of CT and the concordance rate of the subtype classification of CSD were evaluated using surgical findings as the reference standard. Sixty-five patients without CSD who underwent cardiac valve surgery were used as a control group. An incremental value of CT over echocardiography was described retrospectively. Sensitivity and specificity of CT for diagnosis of CSD were 95 % and 100 %, respectively. The concordance rate of subtype classification was 91 % in CT and 92 % in echocardiography. The maximum size of the defect measured by CT correlated well with surgical measurement (r = 0.82), and the limit of agreement was -0.9 ± 7.42 mm. In comparison with echocardiography, CT was able to detect combined abnormalities in three cases, and exclusively provided correct subtype classification or clarified suspected abnormal findings found on echocardiography in seven cases. Cardiac CT can accurately demonstrates CSD in preoperative adult patients. CT may have an incremental role in preoperative planning, particularly in those with more complex anatomy. (orig.)

  17. Preoperative cardiac computed tomography for demonstration of congenital cardiac septal defect in adults

    Eom, Hye-Joung; Yang, Dong Hyun; Kang, Joon-Won; Lim, Tae-Hwan [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Cardiac Imaging Center, Asan Medical Center, Seoul (Korea, Republic of); Kim, Dae-Hee; Song, Jong-Min; Kang, Duk-Hyun; Song, Jae-Kwan [University of Ulsan College of Medicine, Department of Cardiology and Heart Institute, Cardiac Imaging Center, Asan Medical Center, Seoul (Korea, Republic of); Kim, Joon Bum; Jung, Sung-Ho; Choo, Suk Jung; Chung, Cheol Hyun; Lee, Jae Won [University of Ulsan College of Medicine, Department of Cardiothoracic surgery, Cardiac Imaging Center, Asan Medical Center, Seoul (Korea, Republic of)

    2015-06-01

    We aimed to evaluate the role of preoperative cardiac computed tomography (CT) for adults with congenital cardiac septal defect (CSD). Sixty-five consecutive patients who underwent preoperative CT and surgery for CSD were included. The diagnostic accuracy of CT and the concordance rate of the subtype classification of CSD were evaluated using surgical findings as the reference standard. Sixty-five patients without CSD who underwent cardiac valve surgery were used as a control group. An incremental value of CT over echocardiography was described retrospectively. Sensitivity and specificity of CT for diagnosis of CSD were 95 % and 100 %, respectively. The concordance rate of subtype classification was 91 % in CT and 92 % in echocardiography. The maximum size of the defect measured by CT correlated well with surgical measurement (r = 0.82), and the limit of agreement was -0.9 ± 7.42 mm. In comparison with echocardiography, CT was able to detect combined abnormalities in three cases, and exclusively provided correct subtype classification or clarified suspected abnormal findings found on echocardiography in seven cases. Cardiac CT can accurately demonstrates CSD in preoperative adult patients. CT may have an incremental role in preoperative planning, particularly in those with more complex anatomy. (orig.)

  18. Modelflow underestimates cardiac output in heat-stressed individuals

    Shibasaki, Manabu; Wilson, Thad E; Bundgaard-Nielsen, Morten; Seifert, Thomas; Secher, Niels H; Crandall, Craig G

    2011-01-01

    Modelflow accurately tracks thermodilution-derived cardiac outputs during whole body heat stress. Acute changes of cardiac output were accomplished via lower-body negative pressure (LBNP) during normothermic and heat-stressed conditions. In nine healthy normotensive subjects, arterial pressure was measured...... similar with cardiac outputs measured by thermodilution (6.4 ± 0.8 l/min). The subsequent reduction in cardiac output during LBNP was also similar among these methods. Whole body heat stress elevated internal temperature from 36.6 ± 0.3 to 37.8 ± 0.4°C and increased cardiac output from 6.4 ± 0.8 to 10.......9 ± 2.0 l/min when evaluated with thermodilution (P <0.001). However, the increase in cardiac output estimated from the Modelflow method for both arterial cannulation (2.3 ± 1.1 l/min) and Finometer (1.5 ± 1.2 l/min) was attenuated compared with thermodilution (4.5 ± 1.4 l/min, both P <0.01). Finally...

  19. Age- and gender-specific reference values for cardiac chamber geometry and function using three-dimensional echocardiography

    Badano, Luigi P.

    2014-01-01

    Background. Three-dimensional echocardiography (3DE) enables a comprehensive, accurate and reproducible quantification of cardiac chamber size and function without any geometric assumption about their shape. Superior accuracy and reproducibility of 3DE over stabdard two-dimensional (2DE) approach for cardiac chamber volume measurements in comparison to cardiac magnetic resonance (CMR) has been well documented in a number of studies. Both the European Association of Cardiovascular Imag...

  20. Neuromuscular blockade in cardiac surgery: An update for clinicians

    Hemmerling Thomas

    2008-01-01

    Full Text Available There have been great advancements in cardiac surgery over the last two decades; the widespread use of off-pump aortocoronary bypass surgery, minimally invasive cardiac surgery, and robotic surgery have also changed the face of cardiac anaesthesia. The concept of "Fast-track anaesthesia" demands the use of nondepolarising neuromuscular blocking drugs with short duration of action, combining the ability to provide (if necessary sufficiently profound neuromuscular blockade during surgery and immediate re-establishment of normal neuromuscular transmission at the end of surgery. Postoperative residual muscle paralysis is one of the major hurdles for immediate or early extubation after cardiac surgery. Nondepolarising neuromuscular blocking drugs for cardiac surgery should therefore be easy to titrate, of rapid onset and short duration of action with a pathway of elimination independent from hepatic or renal dysfunction, and should equally not affect haemodynamic stability. The difference between repetitive bolus application and continuous infusion is outlined in this review, with the pharmacodynamic and pharmacokinetic characteristics of vecuronium, pancuronium, rocuronium, and cisatracurium. Kinemyography and acceleromyography are the most important currently used neuromuscular monitoring methods. Whereas monitoring at the adductor pollicis muscle is appropriate at the end of surgery, monitoring of the corrugator supercilii muscle better reflects neuromuscular blockade at more central, profound muscles, such as the diaphragm, larynx, or thoraco-abdominal muscles. In conclusion, cisatracurium or rocuronium is recommended for neuromuscular blockade in modern cardiac surgery.

  1. Automated detection of cardiac phase from intracoronary ultrasound image sequences.

    Sun, Zheng; Dong, Yi; Li, Mengchan

    2015-01-01

    Intracoronary ultrasound (ICUS) is a widely used interventional imaging modality in clinical diagnosis and treatment of cardiac vessel diseases. Due to cyclic cardiac motion and pulsatile blood flow within the lumen, there exist changes of coronary arterial dimensions and relative motion between the imaging catheter and the lumen during continuous pullback of the catheter. The action subsequently causes cyclic changes to the image intensity of the acquired image sequence. Information on cardiac phases is implied in a non-gated ICUS image sequence. A 1-D phase signal reflecting cardiac cycles was extracted according to cyclical changes in local gray-levels in ICUS images. The local extrema of the signal were then detected to retrieve cardiac phases and to retrospectively gate the image sequence. Results of clinically acquired in vivo image data showed that the average inter-frame dissimilarity of lower than 0.1 was achievable with our technique. In terms of computational efficiency and complexity, the proposed method was shown to be competitive when compared with the current methods. The average frame processing time was lower than 30 ms. We effectively reduced the effect of image noises, useless textures, and non-vessel region on the phase signal detection by discarding signal components caused by non-cardiac factors. PMID:26406038

  2. Cardiac arrest in children

    Tress Erika

    2010-01-01

    Full Text Available Major advances in the field of pediatric cardiac arrest (CA were made during the last decade, starting with the publication of pediatric Utstein guidelines, the 2005 recommendations by the International Liaison Committee on Resuscitation, and culminating in multicenter collaborations. The epidemiology and pathophysiology of in-hospital and out-of-hospital CA are now well described. Four phases of CA are described and the term "post-cardiac arrest syndrome" has been proposed, along with treatment goals for each of its four phases: immediate post-arrest, early post-arrest, intermediate and recovery phase. Hypothermia is recommended to be considered as a therapy for post-CA syndrome in comatose patients after CA, and large multicenter prospective studies are underway. We reviewed landmark articles related to pediatric CA published during the last decade. We present the current knowledge of epidemiology, pathophysiology and treatment of CA relevant to pre-hospital and acute care health practitioners.

  3. Cardiac arrest in children.

    Tress, Erika E; Kochanek, Patrick M; Saladino, Richard A; Manole, Mioara D

    2010-07-01

    Major advances in the field of pediatric cardiac arrest (CA) were made during the last decade, starting with the publication of pediatric Utstein guidelines, the 2005 recommendations by the International Liaison Committee on Resuscitation, and culminating in multicenter collaborations. The epidemiology and pathophysiology of in-hospital and out-of-hospital CA are now well described. Four phases of CA are described and the term "post-cardiac arrest syndrome" has been proposed, along with treatment goals for each of its four phases: immediate post-arrest, early post-arrest, intermediate and recovery phase. Hypothermia is recommended to be considered as a therapy for post-CA syndrome in comatose patients after CA, and large multicenter prospective studies are underway. We reviewed landmark articles related to pediatric CA published during the last decade. We present the current knowledge of epidemiology, pathophysiology and treatment of CA relevant to pre-hospital and acute care health practitioners. PMID:20930971

  4. Socially differentiated cardiac rehabilitation

    Meillier, Lucette Kirsten; Nielsen, Kirsten Melgaard; Larsen, Finn Breinholt;

    2012-01-01

    recruitment and participation among low educated and socially vulnerable patients must be addressed to lower inequality in post-MI health. Our aim was to improve referral, attendance, and adherence rates among socially vulnerable patients by systematic screening and by offering a socially differentiated...... standard rehabilitation programme (SRP). If patients were identified as socially vulnerable, they were offered an extended version of the rehabilitation programme (ERP). Excluded patients were offered home visits by a cardiac nurse. Concordance principles were used in the individualised programme elements......%. Patients were equally distributed to the SRP and the ERP. No inequality was found in attendance and adherence among referred patients. Conclusions: It seems possible to overcome unequal referral, attendance, and adherence in cardiac rehabilitation by organisation of systematic screening and social...

  5. Cardiac metastases of osteosarcoma

    Osteosarcoma is a malignancy whose various sites of metastasis greatly modify its ultimate prognosis. We report a case of simultaneous pulmonary and cardiac metastases in a 41-year-old male patient with osteosarcoma of the tibia, presenting after more then one year of completion of adjuvant therapy with progressive dyspnea and cyanosis. Diagnosis was made on computerized tomogram and echocardiogram. The metastatic mass entirely occupying the right ventricle and the pulmonary artery proved fatal. (author)

  6. Cardiac Tissue Engineering

    MILICA RADISIC; GORDANA VUNJAK-NOVAKOVIC

    2009-01-01

    We hypothesized that clinically sized (1-5 mm thick),compact cardiac constructs containing physiologically high density of viable cells (~108 cells/cm3) can be engineered in vitro by using biomimetic culture systems capable of providing oxygen transport and electrical stimulation, designed to mimic those in native heart. This hypothesis was tested by culturing rat heart cells on polymer scaffolds, either with perfusion of culture medium (physiologic interstitial velocity, supplementation of p...

  7. Cardiac developmental toxicity

    Mahler, Gretchen J.; Jonathan T Butcher

    2011-01-01

    Congenital heart disease is a highly prevalent problem with mostly unknown origins. Many cases of CHD likely involve an environmental exposure coupled with genetic susceptibility, but practical and ethical considerations make nongenetic causes of CHD difficult to assess in humans. The development of the heart is highly conserved across all vertebrate species, making animal models an excellent option for screening potential cardiac teratogens. This review will discuss exposures known to cause ...

  8. Penetrating Cardiac Injuries

    ÖZYAZICIOĞLU, Ahmet

    2002-01-01

    Objectives: To present our experience of penetrating cardiac injuries treated at Atatürk University hospital; in 17 years 38 patients were analyzed. Methods: Patients were classified into three groups: group A (stable), 12; group B (shock), 21; and group C (agonal), five. Five patients were treated by pericardial window and three by pericardiocentesis. Two patients in group C, 19 patients in group B and five patients in group A underwent median sternotomy or thoracotomy in the operating room...

  9. Benign cardiac tumours: cardiac CT and MRI imaging appearances

    Full text: Primary benign cardiac tumours are rarely found in clinical practice and are generally evaluated with echocardiography. However, with the increasing usage of helical multislice CT, the initial detection and evaluation of these masses may be made by the radiologist during routine daily practice for other indications. The echocardiographic, CT and cardiac MRI appearances of various benign cardiac tumours and masses are described and illustrated in this review

  10. Cardiac tissue engineering

    MILICA RADISIC

    2005-03-01

    Full Text Available We hypothesized that clinically sized (1-5 mm thick,compact cardiac constructs containing physiologically high density of viable cells (~108 cells/cm3 can be engineered in vitro by using biomimetic culture systems capable of providing oxygen transport and electrical stimulation, designed to mimic those in native heart. This hypothesis was tested by culturing rat heart cells on polymer scaffolds, either with perfusion of culture medium (physiologic interstitial velocity, supplementation of perfluorocarbons, or with electrical stimulation (continuous application of biphasic pulses, 2 ms, 5 V, 1 Hz. Tissue constructs cultured without perfusion or electrical stimulation served as controls. Medium perfusion and addition of perfluorocarbons resulted in compact, thick constructs containing physiologic density of viable, electromechanically coupled cells, in contrast to control constructs which had only a ~100 mm thick peripheral region with functionally connected cells. Electrical stimulation of cultured constructs resulted in markedly improved contractile properties, increased amounts of cardiac proteins, and remarkably well developed ultrastructure (similar to that of native heart as compared to non-stimulated controls. We discuss here the state of the art of cardiac tissue engineering, in light of the biomimetic approach that reproduces in vitro some of the conditions present during normal tissue development.

  11. Accurate ab initio spin densities

    Boguslawski, Katharina; Legeza, Örs; Reiher, Markus

    2012-01-01

    We present an approach for the calculation of spin density distributions for molecules that require very large active spaces for a qualitatively correct description of their electronic structure. Our approach is based on the density-matrix renormalization group (DMRG) algorithm to calculate the spin density matrix elements as basic quantity for the spatially resolved spin density distribution. The spin density matrix elements are directly determined from the second-quantized elementary operators optimized by the DMRG algorithm. As an analytic convergence criterion for the spin density distribution, we employ our recently developed sampling-reconstruction scheme [J. Chem. Phys. 2011, 134, 224101] to build an accurate complete-active-space configuration-interaction (CASCI) wave function from the optimized matrix product states. The spin density matrix elements can then also be determined as an expectation value employing the reconstructed wave function expansion. Furthermore, the explicit reconstruction of a CA...

  12. Accurate Modeling of Advanced Reflectarrays

    Zhou, Min

    of the incident field, the choice of basis functions, and the technique to calculate the far-field. Based on accurate reference measurements of two offset reflectarrays carried out at the DTU-ESA Spherical NearField Antenna Test Facility, it was concluded that the three latter factors are particularly important...... to the conventional phase-only optimization technique (POT), the geometrical parameters of the array elements are directly optimized to fulfill the far-field requirements, thus maintaining a direct relation between optimization goals and optimization variables. As a result, better designs can be obtained compared...... using the GDOT to demonstrate its capabilities. To verify the accuracy of the GDOT, two offset contoured beam reflectarrays that radiate a high-gain beam on a European coverage have been designed and manufactured, and subsequently measured at the DTU-ESA Spherical Near-Field Antenna Test Facility...

  13. Accurate thickness measurement of graphene

    Shearer, Cameron J.; Slattery, Ashley D.; Stapleton, Andrew J.; Shapter, Joseph G.; Gibson, Christopher T.

    2016-03-01

    Graphene has emerged as a material with a vast variety of applications. The electronic, optical and mechanical properties of graphene are strongly influenced by the number of layers present in a sample. As a result, the dimensional characterization of graphene films is crucial, especially with the continued development of new synthesis methods and applications. A number of techniques exist to determine the thickness of graphene films including optical contrast, Raman scattering and scanning probe microscopy techniques. Atomic force microscopy (AFM), in particular, is used extensively since it provides three-dimensional images that enable the measurement of the lateral dimensions of graphene films as well as the thickness, and by extension the number of layers present. However, in the literature AFM has proven to be inaccurate with a wide range of measured values for single layer graphene thickness reported (between 0.4 and 1.7 nm). This discrepancy has been attributed to tip-surface interactions, image feedback settings and surface chemistry. In this work, we use standard and carbon nanotube modified AFM probes and a relatively new AFM imaging mode known as PeakForce tapping mode to establish a protocol that will allow users to accurately determine the thickness of graphene films. In particular, the error in measuring the first layer is reduced from 0.1-1.3 nm to 0.1-0.3 nm. Furthermore, in the process we establish that the graphene-substrate adsorbate layer and imaging force, in particular the pressure the tip exerts on the surface, are crucial components in the accurate measurement of graphene using AFM. These findings can be applied to other 2D materials.

  14. Indeterminacy of Spatiotemporal Cardiac Alternans

    Zhao, Xiaopeng

    2007-01-01

    Cardiac alternans, a beat-to-beat alternation in action potential duration (at the cellular level) or in ECG morphology (at the whole heart level), is a marker of ventricular fibrillation, a fatal heart rhythm that kills hundreds of thousands of people in the US each year. Investigating cardiac alternans may lead to a better understanding of the mechanisms of cardiac arrhythmias and eventually better algorithms for the prediction and prevention of such dreadful diseases. In paced cardiac tissue, alternans develops under increasingly shorter pacing period. Existing experimental and theoretical studies adopt the assumption that alternans in homogeneous cardiac tissue is exclusively determined by the pacing period. In contrast, we find that, when calcium-driven alternans develops in cardiac fibers, it may take different spatiotemporal patterns depending on the pacing history. Because there coexist multiple alternans solutions for a given pacing period, the alternans pattern on a fiber becomes unpredictable. Usin...

  15. Biosynthesis of cardiac natriuretic peptides

    Goetze, Jens Peter

    2010-01-01

    Cardiac-derived peptide hormones were identified more than 25 years ago. An astonishing amount of clinical studies have established cardiac natriuretic peptides and their molecular precursors as useful markers of heart disease. In contrast to the clinical applications, the biogenesis of cardiac p...... competent endocrine cells. The structurally related atrial natriuretic peptide will be mentioned where appropriate, whereas C-type natriuretic peptide will not be considered as a cardiac peptide of relevance in mammalian physiology....... characterized. An ongoing characterization of the molecular heterogeneity will help appreciate the biosynthetic capacity of the endocrine heart and could introduce new diagnostic possibilities. Notably, different biosynthetic products may not be equal markers of the same pathophysiological processes. An...... inefficient post-translational prohormone maturation will also affect the biology of the cardiac natriuretic peptide system. This review aims at summarizing the myocardial synthesis of natriuretic peptides focusing on B-type natriuretic peptide, where new data has disclosed cardiac myocytes as highly...

  16. Biosynthesis of cardiac natriuretic peptides

    Goetze, Jens Peter

    2010-01-01

    Cardiac-derived peptide hormones were identified more than 25 years ago. An astonishing amount of clinical studies have established cardiac natriuretic peptides and their molecular precursors as useful markers of heart disease. In contrast to the clinical applications, the biogenesis of cardiac...... inefficient post-translational prohormone maturation will also affect the biology of the cardiac natriuretic peptide system. This review aims at summarizing the myocardial synthesis of natriuretic peptides focusing on B-type natriuretic peptide, where new data has disclosed cardiac myocytes as highly...... competent endocrine cells. The structurally related atrial natriuretic peptide will be mentioned where appropriate, whereas C-type natriuretic peptide will not be considered as a cardiac peptide of relevance in mammalian physiology....

  17. Sudden Cardiac Death in Athletes.

    Wasfy, Meagan M; Hutter, Adolph M; Weiner, Rory B

    2016-01-01

    There are clear health benefits to exercise; even so, patients with cardiac conditions who engage in exercise and athletic competition may on rare occasion experience sudden cardiac death (SCD). This article reviews the epidemiology and common causes of SCD in specific athlete populations. There is ongoing debate about the optimal mechanism for SCD prevention, specifically regarding the inclusion of the ECG and/or cardiac imaging in routine preparticipation sports evaluation. This controversy and contemporary screening recommendations are also reviewed. PMID:27486488

  18. Cardiac Rehabilitation: Guidelines and Recommendations

    Catherine Monpere

    1998-01-01

    Cardiac rehabilitation has been shown to improve exercise tolerance and symptomatology in patients experiencing angina or heart failure and reduce long term mortality after myocardial infarction, with a good cost-effectiveness ratio. In addition to these `hard' endpoints, cardiac rehabilitation improves the patient's quality of life and risk factor profile through a multifactorial intervention. Indeed, cardiac rehabilitation is no longer restricted to physical reconditioning, but should now b...

  19. Evaluation of cardiac tumors with magnetic resonance imaging

    Luna, Antonio [Clinica Las Nieves, MR Unit, Jaen (Spain); Ribes, Ramon [Reina Sofia Hospital, MR Unit, Radiology Department, Cordoba (Spain); Caro, Pilar [MR Unit, Dadisa, Cadiz (Spain); Vida, Jose [San Juan De Dios Hospital, MR Unit, Resalta, Cordoba (Spain); Erasmus, Jeremy J. [University of Texas, Department of Radiology, Houston, TX (United States)

    2005-07-01

    Primary cardiac neoplasms are rare, and are more commonly benign than malignant. However, metastases are by far the most common cardiac neoplasms. MRI allows evaluation of myocardial infiltration, pericardial involvement and/or extracardiac extension. MRI overcomes the usual limitations of echocardiography and assesses more accurately changes in cardiac function. Specific tumoral characterization is only possible in cases of myxoma, lipoma, fibroma and hemangioma. Suggestive features of malignancy are right side location, extracardiac extension, inhomogeneity in signal intensity of the tumor and pericardial effusion. The use of intravenous contrast material improves tumor characterization and depiction of tumor borders. MRI also allows differentiation of tumor from other nontumoral masses such as intracavitary tumors or fibromuscular elements of the posterior wall of the right atrium. (orig.)

  20. Diagnostic imaging of cardiac hypertrophy

    As imaging techniques for cardiac hypertrophy, the ultrasonic dimension gauze technique, echocardiography, ventriculography and the RI technique including emission RI tomography were outlined. (Chiba, N.)

  1. A Reflective Look at Reflecting Teams

    Pender, Rebecca L.; Stinchfield, Tracy

    2012-01-01

    This article reviewed existing literature and research on the reflecting team process. There is a dearth of empirical research that explores the reflecting team process and the outcome of counseling that uses reflecting teams. Implications of using reflecting teams for counselors, counselor educators, and clients will be discussed. A call for…

  2. A More Accurate Fourier Transform

    Courtney, Elya

    2015-01-01

    Fourier transform methods are used to analyze functions and data sets to provide frequencies, amplitudes, and phases of underlying oscillatory components. Fast Fourier transform (FFT) methods offer speed advantages over evaluation of explicit integrals (EI) that define Fourier transforms. This paper compares frequency, amplitude, and phase accuracy of the two methods for well resolved peaks over a wide array of data sets including cosine series with and without random noise and a variety of physical data sets, including atmospheric $\\mathrm{CO_2}$ concentrations, tides, temperatures, sound waveforms, and atomic spectra. The FFT uses MIT's FFTW3 library. The EI method uses the rectangle method to compute the areas under the curve via complex math. Results support the hypothesis that EI methods are more accurate than FFT methods. Errors range from 5 to 10 times higher when determining peak frequency by FFT, 1.4 to 60 times higher for peak amplitude, and 6 to 10 times higher for phase under a peak. The ability t...

  3. Cardiac manifestations of myotonic dystrophy type 1

    Petri, Helle; Vissing, John; Witting, Nanna; Bundgaard, Henning; Køber, Lars

    2012-01-01

    To estimate the degree of cardiac involvement regarding left ventricular ejection fraction, conduction abnormalities, arrhythmia, risk of sudden cardiac death (SCD) and the associations between cardiac involvement and cytosine-thymine-guanine (CTG)-repeat, neuromuscular involvement, age and gender...

  4. Increased cardiac BNP expression associated with myocardial ischemia

    Goetze, J P; Christoffersen, Christina; Perko, M; Arendrup, H; Rehfeld, J F; Kastrup, J; Nielsen, L B

    2003-01-01

    Congestive heart failure is accompanied by increased cardiac brain natriuretic peptide (BNP) gene expression with elevated plasma concentrations of BNP and its precursor, proBNP. We investigated if myocardial ischemia in the absence of overt heart failure may be another mechanism for increased...... and proBNP concentrations to ventricular, but not atrial, BNP mRNA levels. Plasma BNP and proBNP concentrations were markedly increased in patients with coronary artery disease but without concomitant left ventricular dysfunction. These results are compatible with the notion that myocardial ischemia......, even in the absence of left ventricular dysfunction, augments cardiac BNP gene expression and increases plasma BNP and proBNP concentrations. Thus, elevated BNP and proBNP concentrations do not necessarily reflect heart failure but may also result from cardiac ischemia....

  5. Antifibrinolytics in cardiac surgery

    Achal Dhir

    2013-01-01

    Full Text Available Cardiac surgery exerts a significant strain on the blood bank services and is a model example in which a multi-modal blood-conservation strategy is recommended. Significant bleeding during cardiac surgery, enough to cause re-exploration and/or blood transfusion, increases morbidity and mortality. Hyper-fibrinolysis is one of the important contributors to increased bleeding. This knowledge has led to the use of anti-fibrinolytic agents especially in procedures performed under cardiopulmonary bypass. Nothing has been more controversial in recent times than the aprotinin controversy. Since the withdrawal of aprotinin from the world market, the choice of antifibrinolytic agents has been limited to lysine analogues either tranexamic acid (TA or epsilon amino caproic acid (EACA. While proponents of aprotinin still argue against its non-availability. Health Canada has approved its use, albeit under very strict regulations. Antifibrinolytic agents are not without side effects and act like double-edged swords, the stronger the anti-fibrinolytic activity, the more serious the side effects. Aprotinin is the strongest in reducing blood loss, blood transfusion, and possibly, return to the operating room after cardiac surgery. EACA is the least effective, while TA is somewhere in between. Additionally, aprotinin has been implicated in increased mortality and maximum side effects. TA has been shown to increase seizure activity, whereas, EACA seems to have the least side effects. Apparently, these agents do not differentiate between pathological and physiological fibrinolysis and prevent all forms of fibrinolysis leading to possible thrombotic side effects. It would seem prudent to select the right agent knowing its risk-benefit profile for a given patient, under the given circumstances.

  6. Acute right ventricular myocardial injury and sudden cardiac arrest in a patient with persistent spontaneous coronary vasospasm

    Hung Ming-Yow; Li Ju-Chi; Hao Wen-Rui; Wu Cheng-Hsueh; Hung Ming-Jui

    2011-01-01

    Coronary vasospasm is a rare diagnosis resulting in sudden arrhythmic cardiac arrest. We report a case of a healthy,non-smoking elderly woman resuscitated from arrhythmic cardiac arrest. She had persistent spontaneous coronaxy vasospasm, leading to right ventricular myocardial injury and failure, and shock. She responded quickly to intravenous normal saline bolus infusion, but had irreversible neurological sequelae. Additionally, she had atrial fibrillation preceding ischemic ventricular fibrillation, a rare finding in coronary vasospasm-related cardiac arrest. We suggest immediate coronary angiography of patients in sudden arrhythmic cardiac arrest with acute right ventricular failure for a prompt,accurate diagnosis and appropriate management of the coronary vasospasm.

  7. Single ventricle cardiac defect

    Single ventricle heart is defined as a rare cardiac abnormality with a single ventricle chamber involving diverse functional and physiological defects. Our case is of a ten month-old baby boy who died shortly after admission to the hospital due to vomiting and diarrhoea. Autopsy findings revealed cyanosis of finger nails and ears. Internal examination revealed; large heart, weighing 60 grams, single ventricle, without a septum and upper membranous part. Single ventricle is a rare pathology, hence, this paper aims to discuss this case from a medico-legal point of view. (author)

  8. A system for seismocardiography-based identification of quiescent heart phases: implications for cardiac imaging.

    Wick, Carson A; Su, Jin-Jyh; McClellan, James H; Brand, Oliver; Bhatti, Pamela T; Buice, Ashley L; Stillman, Arthur E; Tang, Xiangyang; Tridandapani, Srini

    2012-09-01

    Seismocardiography (SCG), a representation of mechanical heart motion, may more accurately determine periods of cardiac quiescence within a cardiac cycle than the electrically derived electrocardiogram (EKG) and, thus, may have implications for gating in cardiac computed tomography. We designed and implemented a system to synchronously acquire echocardiography, EKG, and SCG data. The device was used to study the variability between EKG and SCG and characterize the relationship between the mechanical and electrical activity of the heart. For each cardiac cycle, the feature of the SCG indicating Aortic Valve Closure was identified and its time position with respect to the EKG was observed. This position was found to vary for different heart rates and between two human subjects. A color map showing the magnitude of the SCG acceleration and computed velocity was derived, allowing for direct visualization of quiescent phases of the cardiac cycle with respect to heart rate. PMID:22581141

  9. Blunt cardiac rupture with prehospital pulseless electrical activity: a rare successful experience.

    Lu, Li-Hua; Choi, Wai-Mau; Wu, Hsueh-Ru; Liu, Hung-Chang; Chiu, Wen-Ta; Tsai, Shin-Han

    2005-12-01

    Blunt cardiac rupture is highly associated with mortality. In the recent literature, the reported mortality rates of cardiac rupture ranged from 59.7% to 100%. The probability of survival for those with prehospital pulseless electrical activity was extremely low. This case report describes a rare example of survival of a female patient with life-threatening cardiac rupture and cardiac tamponade after a major car accident. The victim developed pulseless electrical activity at admission. She recovered from the accident, however, without developing any signs of neurologic deficits. This case study emphasizes the value of the primary survey of patients and prompt and accurate interventions, including focused abdominal sonography for trauma, pericardiocentesis, and an urgent thoracotomy in the operating room for primary repair of cardiac rupture without applying a cardiopulmonary bypass system. The study showed that early diagnosis and aggressive interventions are crucial factors to the successful outcome of patient's survival. PMID:16394928

  10. How accurately can digital images depict conventional radiographs

    The purpose of this paper is to investigate how accurately the video image of a digitized chest radiograph can depict normal anatomic configurations of thoracic organs seen on a conventional radiograph. These configurations are important to diagnosis of diseases of the chest. Chest radiographs of 50 individuals diagnosed as normal were analyzed. Three chest physicians and one radiologist reviewed 50 pairs of digitized images (digitized in 0.125-mm pixel size, 10-bit gray scale, displayed on 1,024 x 1.536, 8-bit gray scale) constructed and conventional films. The visibility of eight structures (spinal process, trachea, right and left main bronchus, anterior tip of right fourth rib, vessels behind diaphragm and cardiac shadow, and descending aorta behind heart) was graded into five levels of confidence

  11. Cardiac causes of pulmonary arterial hypertension: assessment with multidetector CT

    Hoey, Edward T.D.; Gopalan, Deepa; Agrawal, S.K.B. [Papworth Hospital, Cambridge (United Kingdom); Screaton, Nicholas J. [Papworth Hospital, Cambridge (United Kingdom); Papworth Hospital NHS Trust, Diagnostic Centre, Department of Radiology, Papworth Everard, Cambridgeshire (United Kingdom)

    2009-11-15

    The causes of pulmonary arterial hypertension (PAH) are diverse and include multiple congenital and acquired cardiac diseases as well as diseases primarily affecting the pulmonary vasculature, lung, pleura and chest wall. The traditional role of CT in evaluating PAH includes assessment of pulmonary vasculature and lung parenchyma with limited assessment of the heart. Advances in multidetector CT technology with improved spatial and temporal resolution now permit accurate delineation of cardiac morphology. CT pulmonary angiography (CTPA) is widely utilised in the workup of patients with suspected pulmonary vascular disease and can identify both pulmonary and cardiac causes. As the initial presentation for CTPA is often precipitated by nonspecific, unexplained symptoms and therefore undertaken by a general radiologist, it is important that a systematic approach to the interpretation of these studies, including cardiac evaluation, is routinely adopted. This paper reviews the CT evaluation in pulmonary hypertension with a particular focus on the cardiac causes, their subclassification into congenital systemic to pulmonary shunts and secondary to left heart disease, and their imaging features. It emphasises the use of a systematic approach to interpretation of CTPA examinations both in patients with known PAH and those with previously unsuspected disease. (orig.)

  12. Computational modeling of cardiac hemodynamics: Current status and future outlook

    Mittal, Rajat; Seo, Jung Hee; Vedula, Vijay; Choi, Young J.; Liu, Hang; Huang, H. Howie; Jain, Saurabh; Younes, Laurent; Abraham, Theodore; George, Richard T.

    2016-01-01

    The proliferation of four-dimensional imaging technologies, increasing computational speeds, improved simulation algorithms, and the widespread availability of powerful computing platforms is enabling simulations of cardiac hemodynamics with unprecedented speed and fidelity. Since cardiovascular disease is intimately linked to cardiovascular hemodynamics, accurate assessment of the patient's hemodynamic state is critical for the diagnosis and treatment of heart disease. Unfortunately, while a variety of invasive and non-invasive approaches for measuring cardiac hemodynamics are in widespread use, they still only provide an incomplete picture of the hemodynamic state of a patient. In this context, computational modeling of cardiac hemodynamics presents as a powerful non-invasive modality that can fill this information gap, and significantly impact the diagnosis as well as the treatment of cardiac disease. This article reviews the current status of this field as well as the emerging trends and challenges in cardiovascular health, computing, modeling and simulation and that are expected to play a key role in its future development. Some recent advances in modeling and simulations of cardiac flow are described by using examples from our own work as well as the research of other groups.

  13. Identification of patient specific parameters for a minimal cardiac model.

    Hann, C E; Chase, J G; Shaw, G M; Smith, B W

    2004-01-01

    A minimal cardiac model has been developed which accurately captures the essential dynamics of the cardiovascular system (CVS). This paper develops an integral based parameter identification method for fast and accurate identification of patient specific parameters for this minimal model. The integral method is implemented using a single chamber model to prove the concept, and turns a previously nonlinear and nonconvex optimization problem into a linear and convex problem. The method can be readily extended to the full minimal cardiac model and enables rapid identification of model parameters to match a particular patient condition in clinical real time (3-5 minutes). This information can then be used to assist medical staff in understanding, diagnosis and treatment selection. PMID:17271801

  14. A Wearable Contactless Sensor Suitable for Continuous Simultaneous Monitoring of Respiration and Cardiac Activity

    Gargiulo, Gaetano D; Upul Gunawardana; Aiden O’Loughlin; Mohammad Sadozai; Elham Shabani Varaki; Breen, Paul P.

    2015-01-01

    A reliable system that can simultaneously and accurately monitor respiration and cardiac output would have great utility in healthcare applications. In this paper we present a novel approach to creating such a system. This noninvasive, low power, low cost, contactless sensor is suitable for continuous monitoring of respiration (tidal volume) and cardiac stroke volume. Furthermore, it is capable of delivering this data in true volume (i.e., mL). The current embodiment, specifically designed fo...

  15. Focused Cardiac Ultrasound Using a Pocket-Size Device in the Emergency Room

    Mancuso, Frederico José Neves; Siqueira, Vicente Nicoliello; Moisés, Valdir Ambrósio; Gois, Aécio Flavio Teixeira; de Paola, Angelo Amato Vincenzo; Carvalho, Antonio Carlos Camargo; Campos, Orlando

    2014-01-01

    Background Cardiovascular urgencies are frequent reasons for seeking medical care. Prompt and accurate medical diagnosis is critical to reduce the morbidity and mortality of these conditions. Objective To evaluate the use of a pocket-size echocardiography in addition to clinical history and physical exam in a tertiary medical emergency care. Methods One hundred adult patients without known cardiac or lung diseases who sought emergency care with cardiac complaints were included. Patients with ...

  16. Hypokalemia and sudden cardiac death

    Kjeldsen, Keld

    2010-01-01

    Worldwide, approximately three million people suffer sudden cardiac death annually. These deaths often emerge from a complex interplay of substrates and triggers. Disturbed potassium homeostasis among heart cells is an example of such a trigger. Thus, hypokalemia and, also, more transient...... of fatal arrhythmia and sudden cardiac death a patient is, the more attention should be given to the potassium homeostasis....

  17. Cardiac arrest – cardiopulmonary resuscitation

    Basri Lenjani

    2014-01-01

    Conclusions: All survivors from cardiac arrest have received appropriate medical assistance within 10 min from attack, which implies that if cardiac arrest occurs near an institution health care (with an opportunity to provide the emergent health care the rate of survival is higher.

  18. Pneumothorax in cardiac pacing

    Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard;

    2012-01-01

    AIM: To identify risk factors for pneumothorax treated with a chest tube after cardiac pacing device implantation in a population-based cohort.METHODS AND RESULTS: A nationwide cohort study was performed based on data on 28 860 patients from the Danish Pacemaker Register, which included all Danish...... patients who received their first pacemaker (PM) or cardiac resynchronization device from 1997 to 2008. Multiple logistic regression was used to estimate adjusted odds ratios (aOR) with 95% confidence intervals for the association between risk factors and pneumothorax treated with a chest tube. The median...... age was 77 years (25th and 75th percentile: 69-84) and 55% were male (n = 15 785). A total of 190 patients (0.66%) were treated for pneumothorax, which was more often in women [aOR 1.9 (1.4-2.6)], and in patients with age >80 years [aOR 1.4 (1.0-1.9)], a prior history of chronic obstructive pulmonary...

  19. Leadership in cardiac surgery.

    Rao, Christopher; Patel, Vanash; Ibrahim, Michael; Ahmed, Kamran; Wong, Kathie A; Darzi, Ara; von Segesser, Ludwig K; Athanasiou, Thanos

    2011-06-01

    Despite the efficacy of cardiac surgery, less invasive interventions with more uncertain long-term outcomes are increasingly challenging surgery as first-line treatment for several congenital, degenerative and ischemic cardiac diseases. The specialty must evolve if it is to ensure its future relevance. More importantly, it must evolve to ensure that future patients have access to treatments with proven long-term effectiveness. This cannot be achieved without dynamic leadership; however, our contention is that this is not enough. The demands of a modern surgical career and the importance of the task at hand are such that the serendipitous emergence of traditional charismatic leadership cannot be relied upon to deliver necessary change. We advocate systematic analysis and strategic leadership at a local, national and international level in four key areas: Clinical Care, Research, Education and Training, and Stakeholder Engagement. While we anticipate that exceptional individuals will continue to shape the future of our specialty, the creation of robust structures to deliver collective leadership in these key areas is of paramount importance. PMID:20884217

  20. Cardiac chamber scintiscanning

    The two methods of cardiac chamber scintiscanning, i.e. 'first pass' and 'ECG-triggered' examinations, are explained and compared. Two tables indicate the most significant radiation doses of the applied radio tracers, i.e. 99m-Tc-pertechnetate and 99m-Tc-HSA, to which a patient is exposed. These averaged values are calculated from various data given in specialised literature. On the basis of data given in literature, an effective half-life of approximately 5 hours in the intravascular space was calculated for the erythrocytes labelled with technetium 99m. On this basis, the radiation doses for the patients due to 99m-Tc-labelled erythrocytes are estimated. The advantages and disadvantages of the two methods applied for cardiac chamber scintiscanning are put into contrast and compared with the advantages and disadvantages of the quantitative X-ray cardiography of the left heart. The still existing problems connected with the assessment of ECG-triggered images are discussed in detail. The author performed investigations of his own, which concerned the above-mentioned problems. (orig./MG)

  1. Swedish ambulance nurses' experiences of nursing patients suffering cardiac arrest.

    Larsson, Ricard; Engström, Åsa

    2013-04-01

    Effective pre-hospital treatment of a person suffering cardiac arrest is a challenging task for the ambulance nurses. The aim of this study was to describe ambulance nurses' experiences of nursing patients suffering cardiac arrest. Qualitative personal interviews were conducted during 2011 in Sweden with seven ambulance nurses with experience of nursing patients suffering cardiac arrests. The interview texts were analyzed using qualitative thematic content analysis, which resulted in the formulation of one theme with six categories. Mutual preparation, regular training and education were important factors in the nursing of patients suffering cardiac arrest. Ambulance nurses are placed in ethically demanding situations regarding if and for how long they should continue cardio-pulmonary resuscitation (CPR) to accord with pre-hospital cardiac guidelines and patients' wishes. When a cardiac arrest patient is nursed their relatives also need the attention of ambulance nurses. Reflection is one way for ambulance nurses to learn from, and talk about, their experiences. This study provides knowledge of ambulance nurses' experiences in the care of people with cardiac arrest. Better feedback about the care given by the ambulance nurses, and about the diagnosis and nursing care the patients received after they were admitted to the hospital are suggested as improvements that would allow ambulance nurses to learn more from their experience. Further development and research concerning the technical equipment might improve the situation for both the ambulance nurses and the patients. Ambulance nurses need regularly training and education to be prepared for saving people's lives and also to be able to make the right decisions. PMID:23577977

  2. Simulation methods and validation criteria for modeling cardiac ventricular electrophysiology

    Shankarjee Krishnamoorthi; Luigi E Perotti; Nils P Borgstrom; Ajijola, Olujimi A.; Anna Frid; Ponnaluri, Aditya V.; Weiss, James N.; Zhilin Qu; Klug, William S.; Ennis, Daniel B.; Alan Garfinkel

    2014-01-01

    © 2014 Krishnamoorthi et al. We describe a sequence of methods to produce a partial differential equation model of the electrical activation of the ventricles. In our framework, we incorporate the anatomy and cardiac microstructure obtained from magnetic resonance imaging and diffusion tensor imaging of a New Zealand White rabbit, the Purkinje structure and the Purkinje-muscle junctions, and an electrophysiologically accurate model of the ventricular myocytes and tissue, which includes transm...

  3. Cardiac output estimation using pulmonary mechanics in mechanically ventilated patients

    Hann Christopher E; Chase J; Sundaresan Ashwath; Shaw Geoffrey M

    2010-01-01

    Abstract The application of positive end expiratory pressure (PEEP) in mechanically ventilated (MV) patients with acute respiratory distress syndrome (ARDS) decreases cardiac output (CO). Accurate measurement of CO is highly invasive and is not ideal for all MV critically ill patients. However, the link between the PEEP used in MV, and CO provides an opportunity to assess CO via MV therapy and other existing measurements, creating a CO measure without further invasiveness. This paper examines...

  4. Affect intensity and cardiac arousal.

    Blascovich, J; Brennan, K; Tomaka, J; Kelsey, R M; Hughes, P; Coad, M L; Adlin, R

    1992-07-01

    Relationships between affect intensity and basal, evoked, and perceived cardiac arousal were investigated in 3 experiments. Affect intensity was assessed using Larsen and Diener's (1987) Affect Intensity Measure (AIM). Cardiac arousal was evoked with exercise in the 1st study and with mental arithmetic in the 2nd and 3rd. Perceived cardiac arousal was measured under optimal conditions using a standard heartbeat discrimination procedure. Women as a group scored higher on the AIM. Affect intensity was unrelated to basal or evoked cardiac arousal and was negatively related to perceived cardiac arousal in all 3 studies. Data suggest that affect intensity, although unrelated to actual physiological arousal, is negatively related to the accuracy with which individuals perceive their own arousal. Results are discussed within the context of an expanded arousal-regulation model (Blascovich, 1990). PMID:1494983

  5. Effect of myocardial perfusion and metabolic interventions on cardiac kinetics of phenylpentadecanoic acid (IPPA) I 123

    Reske, S.N.; Schoen, S.; Schmitt, W.; Knopp, R.; Winkler, C.; Machulla, H.J.

    1986-08-01

    The effect of regional myocardial perfusion and flow-independent adrenergic stimulation, as well as lactate-mediated inhibition of cardiac lipolysis, on cardiac IPPA uptake and metabolism was examined in canine hearts (flow studies) and in the isolated perfused Langendorff rat heart (metabolic interventions). In both normal and ischaemic myocardium, local perfusion is a major determinant of cardiac IPPA uptake. In pacing-induced hyperaemia, the strict flow-dependence of cardiac IPPA uptake is not preserved. Adrenergic stimulation raises the rate of oxidation of both palmitic acid /sup 14/C and IPPA. This change is reflected by increased metabolite production released into the perfusate and radioactivity clearance recorded externally. Lactate in high concentrations exerts the opposite effect on cardiac free fatty acid oxidation. IPPA is stored in this condition preferentially in tissue phospholipids and triglycerides.

  6. Cardiac parasympathetic reactivation following exercise: implications for training prescription.

    Stanley, Jamie; Peake, Jonathan M; Buchheit, Martin

    2013-12-01

    The objective of exercise training is to initiate desirable physiological adaptations that ultimately enhance physical work capacity. Optimal training prescription requires an individualized approach, with an appropriate balance of training stimulus and recovery and optimal periodization. Recovery from exercise involves integrated physiological responses. The cardiovascular system plays a fundamental role in facilitating many of these responses, including thermoregulation and delivery/removal of nutrients and waste products. As a marker of cardiovascular recovery, cardiac parasympathetic reactivation following a training session is highly individualized. It appears to parallel the acute/intermediate recovery of the thermoregulatory and vascular systems, as described by the supercompensation theory. The physiological mechanisms underlying cardiac parasympathetic reactivation are not completely understood. However, changes in cardiac autonomic activity may provide a proxy measure of the changes in autonomic input into organs and (by default) the blood flow requirements to restore homeostasis. Metaboreflex stimulation (e.g. muscle and blood acidosis) is likely a key determinant of parasympathetic reactivation in the short term (0-90 min post-exercise), whereas baroreflex stimulation (e.g. exercise-induced changes in plasma volume) probably mediates parasympathetic reactivation in the intermediate term (1-48 h post-exercise). Cardiac parasympathetic reactivation does not appear to coincide with the recovery of all physiological systems (e.g. energy stores or the neuromuscular system). However, this may reflect the limited data currently available on parasympathetic reactivation following strength/resistance-based exercise of variable intensity. In this review, we quantitatively analyse post-exercise cardiac parasympathetic reactivation in athletes and healthy individuals following aerobic exercise, with respect to exercise intensity and duration, and fitness

  7. A method for accurate, non-destructive diagnosis of congenital heart defects from heart specimens

    Schleich, Jean-Marc; Abdulla, Tariq; Houyel, Lucile; Paul, Jean-François; Summers, Ron; Dillenseger, Jean-Louis

    2013-01-01

    International audience The accurate analysis of congenital heart defect (CHD) specimens is often difficult and up to now required the opening of the heart. The objective of this study is to define a non-destructive method that allows for the precise analysis of each specimen and its different cardiac components in order to improve classification of the defect and thus provide an indication of underpinning causal mechanisms. We propose a method in which the heart volume is acquired by a CT ...

  8. Threshold adjusted calcium scoring using CT is less susceptible to cardiac motion and more accurate

    Groen, J. M.; Dijkstra, H.; Greuter, M. J. W.; Oudkerk, M.

    2009-01-01

    The purpose of this paper is to investigate calcium scoring on computed tomography (CT) using an adjusted threshold depending on the maximum Hounsfield value within the calcification (HU(peak)). The volume of 19 calcifications was retrospectively determined on 64-slice multidetector CT and dual sour

  9. Planar Reflection of Gaseous Detonations

    Damazo, Jason Scott

    Pipes containing flammable gaseous mixtures may be subjected to internal detonation. When the detonation normally impinges on a closed end, a reflected shock wave is created to bring the flow back to rest. This study built on the work of Karnesky (2010) and examined deformation of thin-walled stainless steel tubes subjected to internal reflected gaseous detonations. A ripple pattern was observed in the tube wall for certain fill pressures, and a criterion was developed that predicted when the ripple pattern would form. A two-dimensional finite element analysis was performed using Johnson-Cook material properties; the pressure loading created by reflected gaseous detonations was accounted for with a previously developed pressure model. The residual plastic strain between experiments and computations was in good agreement. During the examination of detonation-driven deformation, discrepancies were discovered in our understanding of reflected gaseous detonation behavior. Previous models did not accurately describe the nature of the reflected shock wave, which motivated further experiments in a detonation tube with optical access. Pressure sensors and schlieren images were used to examine reflected shock behavior, and it was determined that the discrepancies were related to the reaction zone thickness extant behind the detonation front. During these experiments reflected shock bifurcation did not appear to occur, but the unfocused visualization system made certainty impossible. This prompted construction of a focused schlieren system that investigated possible shock wave-boundary layer interaction, and heat-flux gauges analyzed the boundary layer behind the detonation front. Using these data with an analytical boundary layer solution, it was determined that the strong thermal boundary layer present behind the detonation front inhibits the development of reflected shock wave bifurcation.

  10. 38 CFR 4.46 - Accurate measurement.

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Accurate measurement. 4... RATING DISABILITIES Disability Ratings The Musculoskeletal System § 4.46 Accurate measurement. Accurate measurement of the length of stumps, excursion of joints, dimensions and location of scars with respect...

  11. Capnography during cardiac resuscitation: a clue on mechanisms and a guide to interventions

    Gazmuri, Raúl J.; Kube, Erika

    2003-01-01

    Measurement of the end-tidal partial pressure of carbon dioxide (PETCO2) during cardiac arrest has been shown to reflect the blood flow being generated by external means and to prognosticate outcome. In the present issue of Critical Care, Grmec and colleagues compared the initial and subsequent PETCO2 in patients who had cardiac arrest precipitated by either asphyxia or ventricular arrhythmia. A much higher PETCO2 was found immediately after intubation in instances of asphyxial arrest. Yet, a...

  12. An improved thin film approximation to accurately determine the optical conductivity of graphene from infrared transmittance

    Weber, J. W.; Bol, A. A.; M. C. M. van de Sanden,

    2014-01-01

    This work presents an improved thin film approximation to extract the optical conductivity from infrared transmittance in a simple yet accurate way. This approximation takes into account the incoherent reflections from the backside of the substrate. These reflections are shown to have a significant

  13. Cardiac potassium channel subtypes

    Schmitt, Nicole; Grunnet, Morten; Olesen, Søren-Peter

    2014-01-01

    About 10 distinct potassium channels in the heart are involved in shaping the action potential. Some of the K(+) channels are primarily responsible for early repolarization, whereas others drive late repolarization and still others are open throughout the cardiac cycle. Three main K(+) channels...... drive the late repolarization of the ventricle with some redundancy, and in atria this repolarization reserve is supplemented by the fairly atrial-specific KV1.5, Kir3, KCa, and K2P channels. The role of the latter two subtypes in atria is currently being clarified, and several findings indicate that...... they could constitute targets for new pharmacological treatment of atrial fibrillation. The interplay between the different K(+) channel subtypes in both atria and ventricle is dynamic, and a significant up- and downregulation occurs in disease states such as atrial fibrillation or heart failure. The...

  14. Trends in Cardiac Pacemaker Batteries

    Venkateswara Sarma Mallela

    2004-10-01

    Full Text Available Batteries used in Implantable cardiac pacemakers-present unique challenges to their developers and manufacturers in terms of high levels of safety and reliability. In addition, the batteries must have longevity to avoid frequent replacements. Technological advances in leads/electrodes have reduced energy requirements by two orders of magnitude. Micro-electronics advances sharply reduce internal current drain concurrently decreasing size and increasing functionality, reliability, and longevity. It is reported that about 600,000 pacemakers are implanted each year worldwide and the total number of people with various types of implanted pacemaker has already crossed 3 million. A cardiac pacemaker uses half of its battery power for cardiac stimulation and the other half for housekeeping tasks such as monitoring and data logging. The first implanted cardiac pacemaker used nickel-cadmium rechargeable battery, later on zinc-mercury battery was developed and used which lasted for over 2 years. Lithium iodine battery invented and used by Wilson Greatbatch and his team in 1972 made the real impact to implantable cardiac pacemakers. This battery lasts for about 10 years and even today is the power source for many manufacturers of cardiac pacemakers. This paper briefly reviews various developments of battery technologies since the inception of cardiac pacemaker and presents the alternative to lithium iodine battery for the near future.

  15. Is it Safe? Adverse drug effects and cardiac arrhythmias

    Varkevisser, R.

    2014-01-01

    The potentially life-threatening polymorphic ventricular arrhythmia Torsade de Pointes (TdP) generally occurs in the setting of delayed ventricular repolarization, as reflected on the ECG by a prolonged QT interval. A growing number of drugs are associated with QT prolongation and/or TdP, as a result, development of promising new drugs has been aborted, and already marketed drugs have received severe restrictions or have been withdrawn. To address this cardiac safety issue, international guid...

  16. Platelets and cardiac arrhythmia

    JonasSDe Jong

    2010-12-01

    Full Text Available Sudden cardiac death remains one of the most prevalent modes of death in industrialized countries, and myocardial ischemia due to thrombotic coronary occlusion is its primary cause. The role of platelets in the occurrence of SCD extends beyond coronary flow impairment by clot formation. Here we review the substances released by platelets during clot formation and their arrhythmic properties. Platelet products are released from three types of platelet granules: dense core granules, alpha-granules, and platelet lysosomes. The physiologic properties of dense granule products are of special interest as a potential source of arrhythmic substances. They are released readily upon activation and contain high concentrations of serotonin, histamine, purines, pyrimidines, and ions such as calcium and magnesium. Potential arrhythmic mechanisms of these substances, e.g. serotonin and high energy phosphates, include induction of coronary constriction, calcium overloading, and induction of delayed after-depolarizations. Alpha-granules produce thromboxanes and other arachidonic acid products with many potential arrhythmic effects mediated by interference with cardiac sodium, calcium and potassium channels. Alpha-granules also contain hundreds of proteins that could potentially serve as ligands to receptors on cardiomyocytes. Lysosomal products probably do not have an important arrhythmic effect. Platelet products and ischemia can induce coronary permeability, thereby enhancing interaction with surrounding cardiomyocytes. Antiplatelet therapy is known to improve survival after myocardial infarction. Although an important part of this effect results from prevention of coronary clot formation, there is evidence to suggest that antiplatelet therapy also induces anti-arrhythmic effects during ischemia by preventing the release of platelet activation products.

  17. A New Frontier for Cardiac Monitoring

    2001-01-01

    CardioDynamics International Corporation (CDIC) has created the BioZ(TM) System through a Small Business Innovation Research (SBIR) award from Johnson Space Center, providing patients and physicians with a cost-effective and highly accurate monitoring system.The BioZ non-invasive heart monitor is based on a technology known as Impedance Cardiography (ICG). BioZ provides the physician with vital information about the heart's ability to deliver blood to the body, the force one's heart exerts with each beat, and the amount of fluid in the chest. Specially designed bioimpedance sensors placed on the neck and chest monitor 12 different parameters, including cardiac output, contractility, systemic vascular resistance, and thoracic fluid content. These sensors monitor the electrical conductivity of the body-information that is converted into blood flow data and is displayed in real time on a monitoring screen. BioZ.com(TM) and BioZ.pc(TM) are two additional products that incorporate the same sensors present in the original BioZ system. The "com" in BioZ.com stands for cardiac output monitor. This fully integrated system is essentially a smaller version of the BioZ, combining the same abilities with a compact, lightweight design, while providing greater portability.

  18. Magnetic resonance imaging of congenital cardiac abnormalities

    Magnetic resonance imaging will not replace echocardiography as the simplest and most definitive method of establishing a noninvasive diagnosis in young patients with congenital cardiac malformations, nor will it replace radionuclide angiography for relatively noninvasive detection and quantitation of cardiac shunts. Magnetic resonance imaging is a complementary noninvasive imaging procedure that can answer some questions left in doubt by echocardiography (mainly extracardiac artery and vein assessments) or radionuclide angiography and used as a preferred follow-up imaging method in certain clinical circumstances. In addition, MRI can be a first-line modality for cardiovascular imaging in older patients in whom adequate echo windows are not available. Angiocardiography remains necessary to provide vital physiological data, i.e., chamber pressures, shunt volumes, oxygen saturations, and pulmonary vascular resistance; however, MRI could negate some follow-up catheterizations in appropriate clinical circumstances. High-resolution proton MRI tomography should ultimately permit the accurate evaluation of ventricular volumes, myocardial mass, and the assessment of regional wall motion and ejection fractions. Paramagnetic substances such as manganese ion may ultimately provide a basis for myocardial perfusion imaging. The potential for MRI evaluation of tissue characterization, noninvasive blood-flow measurements, and myocardial metabolism assessment in intriguing and awaits clinical evaluation

  19. Predicting the risk of sudden cardiac death.

    Lerma, Claudia; Glass, Leon

    2016-05-01

    Sudden cardiac death (SCD) is the result of a change of cardiac activity from normal (typically sinus) rhythm to a rhythm that does not pump adequate blood to the brain. The most common rhythms leading to SCD are ventricular tachycardia (VT) or ventricular fibrillation (VF). These result from an accelerated ventricular pacemaker or ventricular reentrant waves. Despite significant efforts to develop accurate predictors for the risk of SCD, current methods for risk stratification still need to be improved. In this article we briefly review current approaches to risk stratification. Then we discuss the mathematical basis for dynamical transitions (called bifurcations) that may lead to VT and VF. One mechanism for transition to VT or VF involves a perturbation by a premature ventricular complex (PVC) during sinus rhythm. We describe the main mechanisms of PVCs (reentry, independent pacemakers and abnormal depolarizations). An emerging approach to risk stratification for SCD involves the development of individualized dynamical models of a patient based on measured anatomy and physiology. Careful analysis and modelling of dynamics of ventricular arrhythmia on an individual basis will be essential in order to improve risk stratification for SCD and to lay a foundation for personalized (precision) medicine in cardiology. PMID:26660287

  20. Metoclopramide-induced cardiac arrest

    Martha M. Rumore

    2011-11-01

    Full Text Available The authors report a case of cardiac arrest in a patient receiving intravenous (IV metoclopramide and review the pertinent literature. A 62-year-old morbidly obese female admitted for a gastric sleeve procedure, developed cardiac arrest within one minute of receiving metoclopramide 10 mg via slow intravenous (IV injection. Bradycardia at 4 beats/min immediately appeared, progressing rapidly to asystole. Chest compressions restored vital function. Electrocardiogram (ECG revealed ST depression indicative of myocardial injury. Following intubation, the patient was transferred to the intensive care unit. Various cardiac dysrrhythmias including supraventricular tachycardia (SVT associated with hypertension and atrial fibrillation occurred. Following IV esmolol and metoprolol, the patient reverted to normal sinus rhythm. Repeat ECGs revealed ST depression resolution without pre-admission changes. Metoclopramide is a non-specific dopamine receptor antagonist. Seven cases of cardiac arrest and one of sinus arrest with metoclopramide were found in the literature. The metoclopramide prescribing information does not list precautions or adverse drug reactions (ADRs related to cardiac arrest. The reaction is not dose related but may relate to the IV administration route. Coronary artery disease was the sole risk factor identified. According to Naranjo, the association was possible. Other reports of cardiac arrest, severe bradycardia, and SVT were reviewed. In one case, five separate IV doses of 10 mg metoclopramide were immediately followed by asystole repeatedly. The mechanism(s underlying metoclopramide’s cardiac arrest-inducing effects is unknown. Structural similarities to procainamide may play a role. In view of eight previous cases of cardiac arrest from metoclopramide having been reported, further elucidation of this ADR and patient monitoring is needed. Our report should alert clinicians to monitor patients and remain diligent in surveillance and

  1. Cardiac perioperative complications in noncardiac surgery

    Radovanović Dragana; Kolak Radmila; Stokić Aleksandar; Radovanović Zoran; Jovanović Gordana

    2008-01-01

    Anesthesiologists are confronted with an increasing population of patients undergoing noncardiac surgery who are at risk for cardiac complications in the perioperative period. Perioperative cardiac complications are responsible for significant mortality and morbidity. The aim of the present study was to determine the incidence of perioperative (operative and postoperative) cardiac complications and correlations between the incidence of perioperative cardiac complications and type of surgical ...

  2. Reflectance spectra of subarctic lichens

    Lichens constitute a major portion of the ground cover of high latitude environments, but little has been reported concerning their in situ solar spectral reflectance properties. Knowledge of these properties is important for the interpretation of remotely sensed observations from high latitude regions, as well as in studies of high latitude ecology and energy balance climatology. The spectral reflectance of common boreal vascular plants is similar to that of vascular plants of the mid latitudes. The dominant lichens, in contrast, display variable reflectance patterns in visible wavelengths. The relative reflectance peak at 0.55 μm, common to green vegetation, is absent or indistinct in spectra of pervasive boreal forest and tundra lichens, despite the presence of chlorophyll in the inner algal cells. Lichens of the dominant genus, Cladina, display strong absorption of ultraviolet energy and short-wavelength blue light relative to their absorption in other visible wavelengths. Since the Cladinae dominate both the surface vegetation in open woodlands of the boreal forest and the low arctic tundra, their unusual spectral reflectance patterns will enable accurate monitoring of the boreal forest-tundra ecotone and detection of its vigor and movement in the future. (author)

  3. Epigenetic regulation in cardiac fibrosis

    Li-Ming; Yu; Yong; Xu

    2015-01-01

    Cardiac fibrosis represents an adoptive response in the heart exposed to various stress cues. While resolution of the fibrogenic response heralds normalization of heart function, persistent fibrogenesis is usually associated with progressive loss of heart function and eventually heart failure. Cardiac fibrosis is regulated by a myriad of factors that converge on the transcription of genes encoding extracellular matrix proteins, a process the epigenetic machinery plays a pivotal role. In this minireview, we summarize recent advances regarding the epigenetic regulation of cardiac fibrosis focusing on the role of histone and DNA modifications and non-coding RNAs.

  4. MRI determination of cardiac dimensions. 5

    MR images in cardiac function studies allow for precise alignment in reproducible axial planes, with excellent resolution and without areas of signal loss, so that highly accurate measurements can be made. This is important particularly in patients with regional functional deficits, in whom precise depiction of function in each myocardial region without overlap or signal 'drop-out' is critical. Also, MR tomograms make possible the elimination of geometric assumptions, which lead to errors when regional dysfunction is present, in assessment of ventricular volume and ejection fraction. The development of improved temporal resolution and motion display by cine MRI and, in particular, echo-planar techniques has made the measurement of function MRI a valuable clinical method. (author). 36 refs.; 7 figs.; 1 tab

  5. Orientations to Reflective Practice.

    Wellington, Bud; Austin, Patricia

    1996-01-01

    Delineates five orientations to reflective practice: immediate, technical, deliberative, dialectic, and transpersonal, each reflecting different social science bases and beliefs and values about education. Views them as interactive, interdependent, noncompeting, aspects of reflective practice. (SK)

  6. Cardiac catheterization and angiography. Third edition

    This book discusses the papers on cardiac catheterization and angiography. The topics covered are: historical perspective and present practice of cardiac catheterization; angiography principles and utilization of radiologic and cineangiographic equipment; complications, incidence and prevention of side effects of cardiac catheterization; techniques; blood flow measurement of heart; pressure measurement; diagnostic techniques of angiography; special catheter techniques; coronary angiography, temporary and permanent pacemakers, potential role of lasers in the cardiac catheterization and evaluation of cardiac function

  7. Antifibrotic therapies to control cardiac fibrosis

    Fan, Zhaobo; Guan, Jianjun

    2016-01-01

    Cardiac fibrosis occurs naturally after myocardial infarction. While the initially formed fibrotic tissue prevents the infarcted heart tissue from rupture, the progression of cardiac fibrosis continuously expands the size of fibrotic tissue and causes cardiac function decrease. Cardiac fibrosis eventually evolves the infarcted hearts into heart failure. Inhibiting cardiac fibrosis from progressing is critical to prevent heart failure. However, there is no efficient therapeutic approach curren...

  8. Robotic Applications in Cardiac Surgery

    Alan P. Kypson

    2008-11-01

    Full Text Available Traditionally, cardiac surgery has been performed through a median sternotomy, which allows the surgeon generous access to the heart and surrounding great vessels. As a paradigm shift in the size and location of incisions occurs in cardiac surgery, new methods have been developed to allow the surgeon the same amount of dexterity and accessibility to the heart in confined spaces and in a less invasive manner. Initially, long instruments without pivot points were used, however, more recent robotic telemanipulation systems have been applied that allow for improved dexterity, enabling the surgeon to perform cardiac surgery from a distance not previously possible. In this rapidly evolving field, we review the recent history and clinical results of using robotics in cardiac surgery.

  9. Cardiac manifestations in systemic sclerosis

    Sevdalina; Lambova

    2014-01-01

    Primary cardiac involvement, which develops as a direct consequence of systemic sclerosis(SSc), may manifest as myocardial damage, fibrosis of the conduction system, pericardial and, less frequently, as valvular disease. In addition, cardiac complications in SSc may develop as a secondary phenomenon due to pulmonary arterial hypertension and kidney pathology. The prevalence of primary cardiac involvement in SSc is variable and difficult to determine because of the diversity of cardiac manifestations, the presence of subclinical periods, the type of diagnostic tools applied, and the diversity of patient populations. When clinically manifested, cardiac involvement is thought to be an important prognostic factor. Profound microvascular disease is a pathognomonic feature of SSc, as both vasospasm and structural alterations are present. Such alterations are thought to predict macrovascular atherosclerosis over time. There are contradictory reports regarding the prevalence of atherosclerosis in SSc. According to some authors, the prevalence of atherosclerosis of the large epicardial coronary arteries is similar to that of the general population, in contrast with other rheumatic diseases such as rheumatoid arthritis and systemic lupus erythematosus. However, the level of inflammation in SSc is inferior. Thus, the atherosclerotic process may not be as aggressive and not easily detectable in smaller studies. Echocardiography(especially tissue Doppler imaging), single-photon emission computed tomography, magnetic resonance imaging and cardiac computed tomography are sensitive techniques for earlier detection of both structural and functional scleroderma-related cardiac pathologies. Screening for subclinical cardiac involvement via modern, sensitive tools provides an opportunity for early diagnosis and treatment, which is of crucial importance for a positive outcome.

  10. Computational Modeling of Cardiac Electromechanics

    Krishnamoorthi, Shankarjee

    2013-01-01

    Cardiac arrhythmias are a leading cause of death worldwide. Notably, the electrophysiologiy and microstructural requirements for a fatal ventricular arrhythmia remain incompletely understood, thereby the treatment remains largely empirical. Standard antiarrhythmic drug therapy has failed to reduce, and in some instances has increased, the incidence of Sudden Cardiac Death (SCD). Hence, a more complete understanding of the mechanisms that foment a fatal arrhythmia is needed and computational m...

  11. Cardiac Biomarkers in Hyperthyroid Cats

    Sangster, Jodi Kirsten

    2013-01-01

    Background: Hyperthyroidism has substantial effects on the circulatory system. The cardiac biomarkers NT-proBNP and troponin I (cTNI) have proven useful in identifying cats with myocardial disease but have not been as extensively investigated in hyperthyroidism.Hypothesis: Plasma NT-proBNP and cTNI concentrations are higher in cats with primary cardiac disease than in cats with hyperthyroidism and higher in cats with hyperthyroidism than in healthy control cats.Animals: Twenty-three hyperthyr...

  12. Current trends in cardiac rehabilitation

    Dafoe, W; Huston, P

    1997-01-01

    Cardiac rehabilitation can reduce mortality and morbidity for patients with many types of cardiac disease cost-effectively, yet is generally underutilized. Rehabilitation is helpful not only for patients who have had a myocardial infarction but also for those with stable angina or congestive heart failure or those who have undergone myocardial revascularization procedures, a heart transplant or heart valve surgery. The beneficial effects of rehabilitation include a reduction in the rate of de...

  13. Gastrointestinal Complications and Cardiac Surgery

    Allen, Sara J.

    2014-01-01

    Gastrointestinal (GI) complications are an uncommon but potentially devastating complication of cardiac surgery. The reported incidence varies between .3% and 5.5% with an associated mortality of .3–87%. A wide range of GI complications are reported with bleeding, mesenteric ischemia, pancreatitis, cholecystitis, and ileus the most common. Ischemia is thought to be the main cause of GI complications with hypoperfusion during cardiac surgery as well as systemic inflammation, hypothermia, drug ...

  14. Cardiac abnormalities after subarachnoid hemorrhage

    Bilt, I.A.C. van der

    2016-01-01

    Aneurysmal subarachnoid hemorrhage(aSAH) is a devastating neurological disease. During the course of the aSAH several neurological and medical complications may occur. Cardiac abnormalities after aSAH are observed often and resemble stress cardiomyopathy or Tako-tsubo cardiomyopathy(Broken Heart Syndrome) that has been described after acute stress. It is a reversible cardiac dysfunction with distinct imaging features(the echocardiographic or left ventricular angiographic image resembles a Tak...

  15. Reflectivity, reflexivity and situated reflective practice

    Malthouse, R; Roffey-Barentsen, J; Watts, DM

    2014-01-01

    This paper describes an aspect of reflective practice referred to as ‘Situated Reflective Practice’ (SRP). The overarching theory is derived from social theories of structuration and reflexivity. In particular, from Giddens’s (1984) theory of structuration, this sees social life as interplay of agency and structure. Discussion of the research reported here centres on the nature of such situated reflection, considers related literature and presents the data collected in a recent small-scale st...

  16. FGF21 and cardiac physiopathology

    Anna ePlanavila

    2015-08-01

    Full Text Available The heart is not traditionally considered either a target or a site of fibroblast growth factor-21 (FGF21 production. However, recent findings indicate that FGF21 can act as a cardiomyokine; that is, it is produced by cardiac cells at significant levels and acts in an autocrine manner on the heart itself. The heart is sensitive to the effects of FGF21, both systemic and locally generated, owing to the expression in cardiomyocytes of β-Klotho, the key co-receptor known to confer specific responsiveness to FGF21 action. FGF21 has been demonstrated to protect against cardiac hypertrophy, cardiac inflammation, and oxidative stress. FGF21 expression in the heart is induced in response to cardiac insults, such as experimental cardiac hypertrophy and myocardial infarction in rodents, as well as in failing human hearts. Intracellular mechanisms involving PPARα and Sirt1 mediate transcriptional regulation of the FGF21 gene in response to exogenous stimuli. In humans, circulating FGF21 levels are elevated in coronary heart disease and atherosclerosis, and are associated with a higher risk of cardiovascular events in patients with type 2 diabetes. These findings provide new insights into the role of FGF21 in the heart and may offer potential therapeutic strategies for cardiac disease.

  17. Physiological and pathological cardiac hypertrophy.

    Shimizu, Ippei; Minamino, Tohru

    2016-08-01

    The heart must continuously pump blood to supply the body with oxygen and nutrients. To maintain the high energy consumption required by this role, the heart is equipped with multiple complex biological systems that allow adaptation to changes of systemic demand. The processes of growth (hypertrophy), angiogenesis, and metabolic plasticity are critically involved in maintenance of cardiac homeostasis. Cardiac hypertrophy is classified as physiological when it is associated with normal cardiac function or as pathological when associated with cardiac dysfunction. Physiological hypertrophy of the heart occurs in response to normal growth of children or during pregnancy, as well as in athletes. In contrast, pathological hypertrophy is induced by factors such as prolonged and abnormal hemodynamic stress, due to hypertension, myocardial infarction etc. Pathological hypertrophy is associated with fibrosis, capillary rarefaction, increased production of pro-inflammatory cytokines, and cellular dysfunction (impairment of signaling, suppression of autophagy, and abnormal cardiomyocyte/non-cardiomyocyte interactions), as well as undesirable epigenetic changes, with these complex responses leading to maladaptive cardiac remodeling and heart failure. This review describes the key molecules and cellular responses involved in physiological/pathological cardiac hypertrophy. PMID:27262674

  18. Cardiac MRI in suspected myocarditis

    Purpose: To evaluate the potential of ECG-gated breath-hold MRI in diagnosing acute myocardidits. Material and methods: Cardiac MRI was performed on 21 consecutive patients with suspected myocarditis. ECG-gated breath-hold T2-weighted images with fat suppression were acquired in 3 standard views. T1-weighted imaging (FLASH) was performed 10 min after IV administration of Gd-DTPA. Laboratory data included creatine kinase, troponin T and serological tests, ECG findings and echocardiography. Imaging findings were retrospectively compared to the discharge diagnoses. Signal alterations were semiquantitatively classified. Results: Acute myocarditis was diagnosed in 9 patients and cardiac sarcoidosis in 2 patients. Late enhancement was observed in 4 patients with acute myocarditis and in both patients with cardiac sarcoidosis. Semiquantitative evaluation revealed 9 true positive, 9 true negative, 1 false positive and 2 false negative results. Conclusion: Cardiac MRI has the potential to detect acute myocarditis and to diagnose cardiac sarcoidosis. Late enhancement of Gd-DTPA can be found in both viral myocarditis and cardiac sarcoidosis. (orig.)

  19. Cardiac imaging. A multimodality approach

    An excellent atlas on modern diagnostic imaging of the heart Written by an interdisciplinary team of experts, Cardiac Imaging: A Multimodality Approach features an in-depth introduction to all current imaging modalities for the diagnostic assessment of the heart as well as a clinical overview of cardiac diseases and main indications for cardiac imaging. With a particular emphasis on CT and MRI, the first part of the atlas also covers conventional radiography, echocardiography, angiography and nuclear medicine imaging. Leading specialists demonstrate the latest advances in the field, and compare the strengths and weaknesses of each modality. The book's second part features clinical chapters on heart defects, endocarditis, coronary heart disease, cardiomyopathies, myocarditis, cardiac tumors, pericardial diseases, pulmonary vascular diseases, and diseases of the thoracic aorta. The authors address anatomy, pathophysiology, and clinical features, and evaluate the various diagnostic options. Key features: - Highly regarded experts in cardiology and radiology off er image-based teaching of the latest techniques - Readers learn how to decide which modality to use for which indication - Visually highlighted tables and essential points allow for easy navigation through the text - More than 600 outstanding images show up-to-date technology and current imaging protocols Cardiac Imaging: A Multimodality Approach is a must-have desk reference for cardiologists and radiologists in practice, as well as a study guide for residents in both fields. It will also appeal to cardiac surgeons, general practitioners, and medical physicists with a special interest in imaging of the heart. (orig.)

  20. Cardiac involvement in myotonic dystrophy

    Lund, Marie; Diaz, Lars Jorge; Ranthe, Mattis Flyvholm;

    2014-01-01

    genetic testing for DM1. Information on incident cardiac diseases was obtained from the NPR. We estimated standardized incidence ratios (SIRs) of cardiac disease compared with the background population, overall and according to selected diagnostic subgroups (cardiomyopathy, heart failure, conduction...... disorders, arrhythmias, and device implantation). In the DM cohort, SIR for any cardiac disease was 3.42 [95% confidence interval (CI) 3.01-3.86]; for a cardiac disease belonging to the selected subgroups 6.91 (95% CI: 5.93-8.01) and for other cardiac disease 2.59 (95% CI: 2.03-3.25). For a cardiac disease...... belonging to the selected subgroups, the risk was particularly high in the first year after DM diagnosis [SIR 15.4 (95% CI: 10.9-21.3)] but remained significantly elevated in subsequent years [SIR 6.07 (95% CI: 5.11-7.16]). The risk was higher in young cohort members [e.g. 20-39 years: SIR 18.1 (95% CI: 12...

  1. Cardiac Biomarkers and Cycling Race

    Caroline Le Goff, Jean-François Kaux, Sébastien Goffaux, Etienne Cavalier

    2015-06-01

    Full Text Available In cycling as in other types of strenuous exercise, there exists a risk of sudden death. It is important both to understand its causes and to see if the behavior of certain biomarkers might highlight athletes at risk. Many reports describe changes in biomarkers after strenuous exercise (Nie et al., 2011, but interpreting these changes, and notably distinguishing normal physiological responses from pathological changes, is not easy. Here we have focused on the kinetics of different cardiac biomarkers: creatin kinase (CK, creating kinase midbrain (CK-MB, myoglobin (MYO, highly sensitive troponin T (hs-TnT and N-terminal brain natriuretic peptide (NT-proBNP. The population studied was a group of young trained cyclists participating in a 177-km cycling race. The group of individuals was selected for maximal homogeneity. Their annual training volume was between 10,000 and 16,000 kilometers. The rhythm of races is comparable and averages 35 km/h, depending on the race’s difficulty. The cardiac frequency was recorded via a heart rate monitor. Three blood tests were taken. The first blood test, T0, was taken approximately 2 hours before the start of the race and was intended to gather values which would act as references for the following tests. The second blood test, T1, was realized within 5 minutes of their arrival. The third and final blood test, T3, was taken 3 hours following their arrival. The CK, CK-MB, MYO, hs-TnT and NT-proBNP were measured on the Roche Diagnostic modular E (Manhein, Germany. For the statistical analysis, an ANOVA and post hoc test of Scheffé were calculated with the Statistica Software version 9.1. We noticed an important significant variation in the cardiac frequency between T0 and T1 (p < 0.0001, T0 and T3 (p < 0.0001, and T1 and T3 (p < 0.01. Table 1 shows the results obtained for the different biomarkers. CK and CK-MB showed significant variation between T0-T1 and T0-T3 (p < 0.0001. Myoglobin increased significantly

  2. Acute kidney injury in septua- and octogenarians after cardiac surgery

    Schmid Christof

    2011-08-01

    Full Text Available Abstract Background An increasing number of septua- and octogenarians undergo cardiac surgery. Acute kidney injury (AKI still is a frequent complication after surgery. We examined the incidence of AKI and its impact on 30-day mortality. Methods A retrospective study between 01/2006 and 08/2009 with 299 octogenarians, who were matched for gender and surgical procedure to 299 septuagenarians at a university hospital. Primary endpoint was AKI after surgery as proposed by the RIFLE definition (Risk, Injury, Failure, Loss, End-stage kidney disease. Secondary endpoint was 30-day mortality. Perioperative mortality was predicted with the logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE. Results Octogenarians significantly had a mean higher logistic EuroSCORE compared to septuagenarians (13.2% versus 8.5%; p -1 × 1.73 m-2. In contrast, septuagenarians showed a slightly higher median body mass index (28 kg × m-2 versus 26 kg × m-2 and were more frequently active smoker at time of surgery (6.4% versus 1.6%, p The RIFLE classification provided accurate risk assessment for 30-day mortality and fair discriminatory power. Conclusions The RIFLE criteria allow identifying patients with AKI after cardiac surgery. The high incidence of AKI in septua- and octogenarians after cardiac surgery should prompt the use of RIFLE criteria to identify patients at risk and should stimulate institutional measures that target AKI as a quality improvement initiative for patients at advanced age.

  3. Cardiac output during exercise

    Siebenmann, C; Rasmussen, P.; Sørensen, H.;

    2015-01-01

    Several techniques assessing cardiac output (Q) during exercise are available. The extent to which the measurements obtained from each respective technique compares to one another, however, is unclear. We quantified Q simultaneously using four methods: the Fick method with blood obtained from the...... right atrium (Q(Fick-M)), Innocor (inert gas rebreathing; Q(Inn)), Physioflow (impedance cardiography; Q(Phys)), and Nexfin (pulse contour analysis; Q(Pulse)) in 12 male subjects during incremental cycling exercise to exhaustion in normoxia and hypoxia (FiO2  = 12%). While all four methods reported a...... progressive increase in Q with exercise intensity, the slopes of the Q/oxygen uptake (VO2) relationship differed by up to 50% between methods in both normoxia [4.9 ± 0.3, 3.9 ± 0.2, 6.0 ± 0.4, 4.8 ± 0.2 L/min per L/min (mean ± SE) for Q(Fick-M), Q(Inn), QP hys and Q(Pulse), respectively; P = 0.001] and...

  4. Modes of collaborative reflection

    Degeling, Martin; Prilla, Michael

    2011-01-01

    In this paper, we describe different modes of collaborative reflection as processes of learning at the workplace. We explain why reflection is a decisive means of learning and - based on the modes we describe - how groups of people can be supported in reflection together. For this, we describe how scheduled, concurrent and spontaneous collaborative reflection can be supported by articulation, guidance and synergizing.

  5. Reflectivity, Reflexivity and Situated Reflective Practice

    Malthouse, Richard; Roffey-Barentsen, Jodi; Watts, Mike

    2014-01-01

    This paper describes an aspect of reflective practice referred to as situated reflective practice. The overarching theory is derived from social theories of structuration and reflexivity. In particular, from Giddens' theory of structuration, which sees social life as an interplay of agency and structure. Discussion of the research reported…

  6. MODIS Solar Reflective Calibration Traceability

    Xiong, Xiaoxiong; Butler, Jim

    2009-01-01

    Long-term climate data records often consist of observations made by multiple sensors. It is, therefore, extremely important to have instrument overlap, to be able to track instrument stability, to quantify, measurement uncertainties, and to establish absolute scale traceable to the International System of Units (SI). The Moderate Resolution Imaging Spectroradiometer (MODIS) is a key instrument for both the Terra and Aqua missions, which were launched in December 1999 and May 2002, respectively. It has 20 reflective solar bands (RSB) with wavelengths from 0.41 to 2.2 micrometers and observes the Earth at three nadir spatial resolutions: 0.25km, 0.5km, and 1km. MODIS RSB on-orbit calibration is reflectance based with reference to the bidirectional reflectance factor (BRF) of its on-board solar diffuser (SD). The SD BRF characterization was made pre-launch by the instrument vendor using reference samples traceable directly to the National Institute of Standards and Technology (NIST). On-orbit SD reflectance degradation is tracked by an on-board solar diffuser monitor (SDSM). This paper provides details of this calibration chain, from prelaunch to on-orbit operation, and associated uncertainty assessments. Using MODIS as an example, this paper also discusses challenges and key design requirements for future missions developed for accurate climate studies.

  7. MODIS solar reflective calibration traceability

    Xiong, Xiaoxiong; Butler, Jim

    2009-08-01

    Long-term climate data records often consist of observations made by multiple sensors. It is, therefore, extremely important to have instrument overlap, to be able to track instrument stability, to quantify measurement uncertainties, and to establish an absolute measurement scale traceable to the International System of Units (SI). The Moderate Resolution Imaging Spectroradiometer (MODIS) is a key instrument for both the Terra and Aqua missions, which were launched in December 1999 and May 2002, respectively. It has 20 reflective solar bands (RSB) with wavelengths from 0.41 to 2.2μm and observes the Earth at three nadir spatial resolutions: 0.25km, 0.5km, and 1km. MODIS RSB on-orbit calibration is reflectance based with reference to the bi-directional reflectance factor (BRF) of its on-board solar diffuser (SD). The SD BRF characterization was made pre-launch by the instrument vendor using reference samples traceable directly to the National Institute of Standards and Technology (NIST). On-orbit SD reflectance degradation is tracked by an on-board solar diffuser stability monitor (SDSM). This paper provides details of this calibration chain, from pre-launch to on-orbit operation, and associated uncertainty assessments. Using MODIS as an example, this paper also discusses challenges and key design requirements for future missions developed for accurate climate studies.

  8. Cardiac rate detection method based on the beam splitter prism

    Yang, Lei; Liu, Xiaohua; Liu, Ming; Zhao, Yuejin; Dong, Liquan; Zhao, Ruirui; Jin, Xiaoli; Zhao, Jingsheng

    2013-09-01

    A new cardiac rate measurement method is proposed. Through the beam splitter prism, the common-path optical system of transmitting and receiving signals is achieved. By the focusing effect of the lens, the small amplitude motion artifact is inhibited and the signal-to-noise is improved. The cardiac rate is obtained based on the PhotoPlethysmoGraphy (PPG). We use LED as the light source and use photoelectric diode as the receiving tube. The LED and the photoelectric diode are on the different sides of the beam splitter prism and they form the optical system. The signal processing and display unit is composed by the signal processing circuit, data acquisition device and computer. The light emitted by the modulated LED is collimated by the lens and irradiates the measurement target through the beam splitter prism. The light reflected by the target is focused on the receiving tube through the beam splitter prism and another lens. The signal received by the photoelectric diode is processed by the analog circuit and obtained by the data acquisition device. Through the filtering and Fast Fourier Transform, the cardiac rate is achieved. We get the real time cardiac rate by the moving average method. We experiment with 30 volunteers, containing different genders and different ages. We compare the signals captured by this method to a conventional PPG signal captured concurrently from a finger. The results of the experiments are all relatively agreeable and the biggest deviation value is about 2bmp.

  9. Fracture prediction of cardiac lead medical devices using Bayesian networks

    A novel Bayesian network methodology has been developed to enable the prediction of fatigue fracture of cardiac lead medical devices. The methodology integrates in-vivo device loading measurements, patient demographics, patient activity level, in-vitro fatigue strength measurements, and cumulative damage modeling techniques. Many plausible combinations of these variables can be simulated within a Bayesian network framework to generate a family of fatigue fracture survival curves, enabling sensitivity analyses and the construction of confidence bounds on reliability predictions. The method was applied to the prediction of conductor fatigue fracture near the shoulder for two market-released cardiac defibrillation leads which had different product performance histories. The case study used recently published data describing the in-vivo curvature conditions and the in-vitro fatigue strength. The prediction results from the methodology aligned well with the observed qualitative ranking of field performance, as well as the quantitative field survival from fracture. This initial success suggests that study of further extension of this method to other medical device applications is warranted. - Highlights: • A new method to simulate the fatigue experience of an implanted cardiac lead. • Fatigue strength and use conditions are incorporated within a Bayesian network. • Confidence bounds reflect the uncertainty in all input parameters. • A case study is presented using market released cardiac leads

  10. Atresia of the bilateral pulmonary veins: a rare and dismal anomaly identified on cardiac CT

    Goo, Hyun Woo; Park, Sang-Hyub; Koo, Hyun Jung; Cho, Young Hoon; Lee, Eunsol [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of)

    2014-08-15

    Imaging findings of bilateral pulmonary vein atresia have not been described. To describe cardiac CT findings and clinical outcomes of bilateral pulmonary vein atresia. Three newborns with bilateral pulmonary vein atresia were encountered at our institution during a period of 8 years. We evaluated prenatal echocardiographic findings, clinical presentations, postnatal echocardiographic findings, chest radiographic findings, cardiac CT findings and clinical outcomes. All newborns presented immediately after birth with severe cyanosis, respiratory distress and acidosis that were unresponsive to medical management. Prenatal and postnatal echocardiographic studies and chest radiography were misleading, inconclusive or nonspecific in making the diagnosis in these children; however cardiac CT clearly demonstrated atresia of the bilateral pulmonary veins with multiple small mediastinal collateral veins and pulmonary edema. Surgical treatments were not feasible for this anomaly. Their clinical outcomes were universally dismal and all infants died within 3 days. Cardiac CT provides an accurate diagnosis of bilateral pulmonary vein atresia and leads to prompt treatment decision in these children. (orig.)

  11. Cardiac fiber tracking using adaptive particle filtering based on tensor rotation invariant in MRI

    Kong, Fanhui; Liu, Wanyu; Magnin, Isabelle E.; Zhu, Yuemin

    2016-03-01

    Diffusion magnetic resonance imaging (dMRI) is a non-invasive method currently available for cardiac fiber tracking. However, accurate and efficient cardiac fiber tracking is still a challenge. This paper presents a probabilistic cardiac fiber tracking method based on particle filtering. In this framework, an adaptive sampling technique is presented to describe the posterior distribution of fiber orientations by adjusting the number and status of particles according to the fractional anisotropy of diffusion. An observation model is then proposed to update the weight of particles by rotating diffusion tensor from the primary eigenvector to a given fiber orientation while keeping the shape of the tensor invariant. The results on human cardiac dMRI show that the proposed method is robust to noise and outperforms conventional streamline and particle filtering techniques.

  12. Atresia of the bilateral pulmonary veins: a rare and dismal anomaly identified on cardiac CT

    Imaging findings of bilateral pulmonary vein atresia have not been described. To describe cardiac CT findings and clinical outcomes of bilateral pulmonary vein atresia. Three newborns with bilateral pulmonary vein atresia were encountered at our institution during a period of 8 years. We evaluated prenatal echocardiographic findings, clinical presentations, postnatal echocardiographic findings, chest radiographic findings, cardiac CT findings and clinical outcomes. All newborns presented immediately after birth with severe cyanosis, respiratory distress and acidosis that were unresponsive to medical management. Prenatal and postnatal echocardiographic studies and chest radiography were misleading, inconclusive or nonspecific in making the diagnosis in these children; however cardiac CT clearly demonstrated atresia of the bilateral pulmonary veins with multiple small mediastinal collateral veins and pulmonary edema. Surgical treatments were not feasible for this anomaly. Their clinical outcomes were universally dismal and all infants died within 3 days. Cardiac CT provides an accurate diagnosis of bilateral pulmonary vein atresia and leads to prompt treatment decision in these children. (orig.)

  13. Current Roles and Future Applications of Cardiac CT: Risk Stratification of Coronary Artery Disease

    Cardiac computed tomography (CT) has emerged as a noninvasive modality for the assessment of coronary artery disease (CAD), and has been rapidly integrated into clinical cares. CT has changed the traditional risk stratification based on clinical risk to image-based identification of patient risk. Cardiac CT, including coronary artery calcium score and coronary CT angiography, can provide prognostic information and is expected to improve risk stratification of CAD. Currently used conventional cardiac CT, provides accurate anatomic information but not functional significance of CAD, and it may not be sufficient to guide treatments such as revascularization. Recently, myocardial CT perfusion imaging, intracoronary luminal attenuation gradient, and CT-derived computed fractional flow reserve were developed to combine anatomical and functional data. Although at present, the diagnostic and prognostic value of these novel technologies needs to be evaluated further, it is expected that all-in-one cardiac CT can guide treatment and improve patient outcomes in the near future

  14. Management of the Low Cardiac Output Syndrome Following Surgery for Congenital Heart Disease.

    Chandler, Heather K; Kirsch, Roxanne

    2016-01-01

    The purpose of this review is to discuss the management of the low cardiac output syndrome (LCOS) following surgery for congenital heart disease. The LCOS is a well-recognized, frequent post-operative complication with an accepted collection of hemodynamic and physiologic aberrations. Approximately 25% of children experience a decrease in cardiac index of less than 2 L/min/m2 within 6-18 hours after cardiac surgery. Post-operative strategies that may be used to manage patients as risk for or in a state of low cardiac output include the use of hemodynamic monitoring, enabling a timely and accurate assessment of cardiovascular function and tissue oxygenation; optimization of ventricular loading conditions; the judicious use of inotropic agents; an appreciation of and the utilization of positive pressure ventilation for circulatory support; and, in some circumstances, mechanical circulatory support. All interventions and strategies should culminate in improving the relationship between oxygen supply and demand, ensuring adequate tissue oxygenation. PMID:26585039

  15. Evaluation of left ventricular volumes and ejection fraction by gated myocardial perfusion SPECT versus cardiac MRI

    It is stated that cardiac MRI imaging can provide accurate estimation of left ventricular (LV) volumes and ejection fraction (EF). The purpose of this study was to evaluate the accuracy of gated myocardial perfusion single photon emission computed tomography (SPECT) for assessment of LV end-diastolic volume (EDV), end-systolic volume (ESV) and EF, using cardiac MRI as the reference methods/(methodology). Gated myocardial perfusion SPECT images were analyzed with two different quantification software, quantitative gated SPECT (QGS) and 4D-MSPECT. Thirty-four consecutive patients were studied. Myocardial perfusion SPECT and cardiac MRI had excellent intra/interobserver reproducibility. Correlation between the results of gated myocardial perfusion SPECT and cardiac MRI were high for EDV and EF. However, ESV and EDV were significantly underestimated by gated myocardial perfusion SPECT compared to cardiac MRI. Moreover, gated myocardial perfusion SPECT overestimated EF for small heart. One reason for the difference in volumes and EF is the delineation of the endocardial border. Cardiac MRI has higher spatial resolution. We should understand the differences of volumes and EF as determined by gated myocardial perfusion SPECT and cardiac MRI. (author)

  16. Computed tomography of cardiac pseudotumors and neoplasms.

    Anavekar, Nandan S; Bonnichsen, Crystal R; Foley, Thomas A; Morris, Michael F; Martinez, Matthew W; Williamson, Eric E; Glockner, James F; Miller, Dylan V; Breen, Jerome F; Araoz, Philip A

    2010-07-01

    Important features of cardiac masses can be clearly delineated on cardiac computed tomography (CT) imaging. This modality is useful in identifying the presence of a mass, its relationship with cardiac and extracardiac structures, and the features that distinguish one type of mass from another. A multimodality approach to the evaluation of cardiac tumors is advocated, with the use of echocardiography, CT imaging and magnetic resonance imaging as appropriately indicated. In this article, various cardiac masses are described, including pseudotumors and true cardiac neoplasms, and the CT imaging findings that may be useful in distinguishing these rare entities are presented. PMID:20705174

  17. Predictors of high sensitivity cardiac troponin T in chronic kidney disease patients: a cross-sectional study in the chronic renal insufficiency cohort (CRIC)

    Dubin, Ruth F.; Li, Yongmei; He, Jiang; Jaar, Bernard G.; Kallem, Radhakrishna; Lash, James P.; Makos, Gail; Rosas, Sylvia E.; Soliman, Elsayed Z.; Townsend, Ray R; Yang, Wei; Go, Alan S.; Keane, Martin; deFilippi, Christopher; Mishra, Rakesh

    2013-01-01

    Abstract Background Cardiac troponin T is independently associated with cardiovascular events and mortality in patients with chronic kidney disease (CKD). Serum levels of high sensitivity cardiac troponin T (hs-TnT) reflect subclinical myocardial injury in ambulatory patients. We sought to determine the distribution and predictors of hs-TnT in CKD patients without overt cardiovascular disease (CVD). Methods We...

  18. Cardiac output monitoring

    Mathews Lailu

    2008-01-01

    Full Text Available Minimally invasive and non-invasive methods of estimation of cardiac output (CO were developed to overcome the limitations of invasive nature of pulmonary artery catheterization (PAC and direct Fick method used for the measurement of stroke volume (SV. The important minimally invasive techniques available are: oesophageal Doppler monitoring (ODM, the derivative Fick method (using partial carbon dioxide (CO 2 breathing, transpulmonary thermodilution, lithium indicator dilution, pulse contour and pulse power analysis. Impedance cardiography is probably the only non-invasive technique in true sense. It provides information about haemodynamic status without the risk, cost and skill associated with the other invasive or minimally invasive techniques. It is important to understand what is really being measured and what assumptions and calculations have been incorporated with respect to a monitoring device. Understanding the basic principles of the above techniques as well as their advantages and limitations may be useful. In addition, the clinical validation of new techniques is necessary to convince that these new tools provide reliable measurements. In this review the physics behind the working of ODM, partial CO 2 breathing, transpulmonary thermodilution and lithium dilution techniques are dealt with. The physical and the physiological aspects underlying the pulse contour and pulse power analyses, various pulse contour techniques, their development, advantages and limitations are also covered. The principle of thoracic bioimpedance along with computation of CO from changes in thoracic impedance is explained. The purpose of the review is to help us minimize the dogmatic nature of practice favouring one technique or the other.

  19. Patient specific fluid-structure ventricular modelling for integrated cardiac care.

    de Vecchi, A; Nordsletten, D A; Razavi, R; Greil, G; Smith, N P

    2013-11-01

    Cardiac diseases represent one of the primary causes of mortality and result in a substantial decrease in quality of life. Optimal surgical planning and long-term treatment are crucial for a successful and cost-effective patient care. Recently developed state-of-the-art imaging techniques supply a wealth of detailed data to support diagnosis. This provides the foundations for a novel approach to clinical planning based on personalisation, which can lead to more tailored treatment plans when compared to strategies based on standard population metrics. The goal of this study is to develop and apply a methodology for creating personalised ventricular models of blood and tissue mechanics to assess patient-specific metrics. Fluid-structure interaction simulations are performed to analyse the diastolic function in hypoplastic left heart patients, who underwent the first stage of a three-step surgical palliation and whose condition must be accurately evaluated to plan further intervention. The kinetic energy changes generated by the blood propagation in early diastole are found to reflect the intraventricular pressure gradient, giving indications on the filling efficiency. This suggests good agreement between the 3D model and the Euler equation, which provides a simplified relationship between pressure and kinetic energy and could, therefore, be applied in the clinical context. PMID:23340962

  20. Understanding reflective practice.

    Nicol, Jacqueline Sian; Dosser, Isabel

    2016-05-01

    The Nursing and Midwifery Council (NMC) requires that nurses and midwives use feedback as an opportunity for reflection and learning, to improve practice. The NMC revalidation process stipulates that practitioners provide examples of how they have achieved this. To reflect in a meaningful way, it is important to understand what is meant by reflection, the skills required, and how reflection can be undertaken successfully. Traditionally, reflection occurs after an event encountered in practice. The authors challenge this perception, suggesting that reflection should be undertaken before, during and after an event. This article provides practical guidance to help practitioners use reflective models to write reflective accounts. It also outlines how the reflective process can be used as a valuable learning tool in preparation for revalidation. PMID:27154119

  1. Animal models of cardiac cachexia.

    Molinari, Francesca; Malara, Natalia; Mollace, Vincenzo; Rosano, Giuseppe; Ferraro, Elisabetta

    2016-09-15

    Cachexia is the loss of body weight associated with several chronic diseases including chronic heart failure (CHF). The cachectic condition is mainly due to loss of skeletal muscle mass and adipose tissue depletion. The majority of experimental in vivo studies on cachexia rely on animal models of cancer cachexia while a reliable and appropriate model for cardiac cachexia has not yet been established. A critical issue in generating a cardiac cachexia model is that genetic modifications or pharmacological treatments impairing the heart functionality and used to obtain the heart failure model might likely impair the skeletal muscle, this also being a striated muscle and sharing with the myocardium several molecular and physiological mechanisms. On the other hand, often, the induction of heart damage in the several existing models of heart failure does not necessarily lead to skeletal muscle loss and cachexia. Here we describe the main features of cardiac cachexia and illustrate some animal models proposed for cardiac cachexia studies; they include the genetic calsequestrin and Dahl salt-sensitive models, the monocrotaline model and the surgical models obtained by left anterior descending (LAD) ligation, transverse aortic constriction (TAC) and ascending aortic banding. The availability of a specific animal model for cardiac cachexia is a crucial issue since, besides the common aspects of cachexia in the different syndromes, each disease has some peculiarities in its etiology and pathophysiology leading to cachexia. Such peculiarities need to be unraveled in order to find new targets for effective therapies. PMID:27317993

  2. Vitamin D and Cardiac Differentiation.

    Kim, Irene M; Norris, Keith C; Artaza, Jorge N

    2016-01-01

    Calcitriol (1,25-dihydroxycholecalciferol or 1,25-D3) is the hormonally active metabolite of vitamin D. Experimental studies of vitamin D receptors and 1,25-D3 establish calcitriol to be a critical regulator of the structure and function of the heart. Clinical studies link vitamin D deficiency with cardiovascular disease (CVD). Emerging evidence demonstrates that calcitriol is highly involved in CVD-related signaling pathways, particularly the Wnt signaling pathway. Addition of 1,25-D3 to cardiomyocyte cells and examination of its effects on cardiomyocytes and mainly Wnt11 signaling allowed the specific characterization of the role of calcitriol in cardiac differentiation. 1,25-D3 is demonstrated to: (i) inhibit cell proliferation without promoting apoptosis; (ii) decrease expression of genes related to the regulation of the cell cycle; (iii) promote formation of cardiomyotubes; (iv) induce expression of casein kinase-1-α1, a negative regulator of the canonical Wnt signaling pathway; and (v) increase expression of noncanonical Wnt11, which has been recognized to induce cardiac differentiation during embryonic development and in adult cells. Thus, it appears that vitamin D promotes cardiac differentiation through negative modulation of the canonical Wnt signaling pathway and upregulation of noncanonical Wnt11 expression. Future work to elucidate the role(s) of vitamin D in cardiovascular disorders will hopefully lead to improvement and potentially prevention of CVD, including abnormal cardiac differentiation in settings such as postinfarction cardiac remodeling. PMID:26827957

  3. Cardiac factors in orthostatic hypotension

    Löllgen, H.; Dirschedl, P.; Koppenhagen, K.; Klein, K. E.

    Cardiac function is determined by preload, afterload, heart rate and contractility. During orthostatic stress, the footward blood shift is compensated for by an increase of afterload. LBNP is widely used to analyze effects of volume displacement during orthostatic stress. Comparisons of invasive ( right heart catheterization) and non-invasive approach (echocardiography) yielded similar changes. Preload and afterload change with graded LBNP, heart rate increases, and stroke volume and cardiac output decrease. Thus, the working point on the left ventricular function curve is shifted to the left and downward, similar to hypovolemia. However, position on the Frank-Starling curve, the unchanged ejection fraction, and the constant Vcf indicate a normal contractile state during LBNP. A decrease of arterial oxygen partial pressure during LBNP shwos impaired ventilation/perfusion ratio. Finally, LBNP induced cardiac and hemodynamic changes can be effectively countermeasured by dihydroergotamine, a potent venoconstrictor. Comparison of floating catheter data with that of echocardiography resulted in close correlation for cardiac output and stroke volume. In addition, cardiac dimensions changed in a similar way during LBNP. From our findings, echocardiography as a non-invasive procedure can reliably used in LBNP and orthostatic stress tests. Some informations can be obtained on borderline values indicating collaps or orthostatic syncope. Early fainters can be differentiated from late fainters by stroke volume changes.

  4. Cardiac Penetrating Injuries and Pseudoaneurysm

    CHEN Shifeng

    2002-01-01

    Objective To discuss the early diagnosis and treatment of cardiac penetrating injuries and pseudoaneurysm. Methods 18 cases of cardiac penetrating injuries, in which 2 cases were complicated with pseudoaneurysm, were diagnosed by emergency operation and color Doppler echocardiography between May 1973 and Dec. 2001 in our hospital. The basis for emergency operation is the injured path locating in cardiac dangerous zone, severe shock or pericardial tamponade. ResultsAmong 18 cases of this study, 17 cases underwent emergency operation. During the operation, 11 cases were found injured in right ventricle, 2 cases were found injured in right atrium, 1 case was found injured in pulmonary artery,4 cases were found injured in left ventricle, 2 cases were found complicated with pseudoaneurysm. 17cases underwent cardiac repair including 1 case of rupture of aneurysm. 1 case underwent elective aneurysm resection. In whole group, 15 cases survived(83.33% ), 3 cases died( 16.67%). The cause of death is mainly hemorrhagic shock. Conclusion Highly suspicious cardiac penetrating injuries or hemopericaridium should undergo direct operative exploration. Pseudoaneurysm should be resected early,which can prevent severe complications.

  5. Clinical cardiac positron emission tomography: State of the art

    Cardiac positron emission tomography (PET) has evolved rapidly from a relatively esoteric research tool into clinical applications providing unique, quantitative information on myocardial perfusion, metabolism, and cell membrane function and having a potentially significant impact on cardiovascular medicine. Although there are many different positron radionuclides for imaging diverse myocardial behavior, three radionuclides have reached accepted clinical utility. Cardiac PET using nitrogen-13-ammonia, rubidium-82, and fluoro-18-deoxyglucose has proved accurate and definitive in multiple university and private-practice sites for diagnosing and assessing severity and location of coronary artery disease in symptomatic or asymptomatic patients, for identifying injured but viable myocardium potentially salvageable by revascularization, and for ruling out clinically significant coronary artery stenosis with a high specificity in patients who might otherwise undergo coronary arteriography to document the absence of significant disease. 89 references

  6. Mechanical Regulation of Cardiac Development

    HuseyinCagatayYalcin

    2014-08-01

    Full Text Available Mechanical forces are an essential contributor to and unavoidable component of cardiac formation, both inducing and orchestrating local and global molecular and cellular changes. Experimental animal studies have contributed substantially to understanding the mechanobiology of heart development. More recent integration of high-resolution imaging modalities with computational modeling has greatly improved our quantitative understanding of hemodynamic flow in heart development. Merging these latest experimental technologies with molecular and genetic signaling analysis will accelerate our understanding of the relationships integrating mechanical and biological signaling for proper cardiac formation. These advances will likely be essential for clinically translatable guidance for targeted interventions to rescue malforming hearts and/or reconfigure malformed circulations for optimal performance. This review summarizes our current understanding on the levels of mechanical signaling in the heart and their roles in orchestrating cardiac development.

  7. Cine MR imaging-current use in cardiac diagnosis

    This paper reviews the current status of cine MR imaging of the heart with special attention to the assessment of cardiac function. Cine MR provides tomographic sectional images with clear distinction between myocardium and flowing blood, and allows accurate volumetry of the cardiac chambers at specific points of the cardiac cycle. From these volume measurements parameters for the cardiac function, such as stroke volumem, ejection fraction, regurgitant fraction and shunt volum are calculated. While determination of chamber volumes can be done using any imaging plane, regional wall motion and wall thickening are evaluated with the short axis images. These images are readily obtained by orienting the slice selective gradient perpendicular to the long axis of the left ventricle. Left ventricular meridional wall stress is also calculated from cine MR images and noninvasive measurements of peak- and end-systolic pressure. Wall stress is an indicator of myocardial function in response to after load and can be used for monitoring patients with myocardial disease, regurgitant valvular disease and hypertension, and might be used to quantitatively assess the response of these diseases to therapy. Diseases causing hypertrophy of the ventricles, such as valvular stenosis, systemic or pulmonary hypertension and hypertrophic cardiomyopathy, can be monitored with cine MR by measuring the myocardial mass. A signal void from high velocity jets is caused by regurgitant or stenotic valvular lesion as well as flow across ventricular or atrial septal defects. Measurement of the dimension of the signal void have been correlated with the severity of regurgitation and can be used for semi-quantitation of these lesions. Due to the inherent contrast between blood and myocardium, high temporal resolution, and acquisition of tomographic images encompassing the entire heart, cine MR can serve as a comprehensive cardiac imaging modality that provides quantitative evaluation of anatomy and

  8. Ca2+ Alternans in a Cardiac Myocyte Model that Uses Moment Equations to Represent Heterogeneous Junctional SR Ca2+

    Huertas, Marco A; Smith, Gregory D.; Györke, Sándor

    2010-01-01

    Multiscale whole-cell models that accurately represent local control of Ca2+-induced Ca2+ release in cardiac myocytes can reproduce high-gain Ca2+ release that is graded with changes in membrane potential. Using a recently introduced formalism that represents heterogeneous local Ca2+ using moment equations, we present a model of cardiac myocyte Ca2+ cycling that exhibits alternating sarcoplasmic reticulum (SR) Ca2+ release when periodically stimulated by depolarizing voltage pulses. The model...

  9. Complications after cardiac implantable electronic device implantations

    Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard;

    2013-01-01

    Complications after cardiac implantable electronic device (CIED) treatment, including permanent pacemakers (PMs), cardiac resynchronization therapy devices with defibrillators (CRT-Ds) or without (CRT-Ps), and implantable cardioverter defibrillators (ICDs), are associated with increased patient...

  10. How Is Sudden Cardiac Arrest Diagnosed?

    ... heart (a sign of CHD). MUGA Test or Cardiac MRI A MUGA (multiple gated acquisition) test shows how ... create pictures of many parts of your heart. Cardiac MRI (magnetic resonance imaging) is a safe procedure that ...

  11. An update on insertable cardiac monitors

    Olsen, Flemming J; Biering-Sørensen, Tor; Krieger, Derk W

    2015-01-01

    Continuous cardiac rhythm monitoring has undergone compelling progress over the past decades. Cardiac monitoring has emerged from 12-lead electrocardiograms being performed at the discretion of the treating physician to in-hospital telemetry, Holter monitoring, prolonged external event monitoring...

  12. Sudden Cardiac Arrest (SCA) Risk Assessment

    ... Find a Specialist Share Twitter Facebook SCA Risk Assessment Sudden Cardiac Arrest (SCA) occurs abruptly and without ... of all ages and health conditions. Start Risk Assessment The Sudden Cardiac Arrest (SCA) Risk Assessment Tool ...

  13. Small pores in soils: Is the physico-chemical environment accurately reflected in biogeochemical models ?

    Weber, Tobias K. D.; Riedel, Thomas

    2015-04-01

    Free water is a prerequesite to chemical reactions and biological activity in earth's upper crust essential to life. The void volume between the solid compounds provides space for water, air, and organisms that thrive on the consumption of minerals and organic matter thereby regulating soil carbon turnover. However, not all water in the pore space in soils and sediments is in its liquid state. This is a result of the adhesive forces which reduce the water activity in small pores and charged mineral surfaces. This water has a lower tendency to react chemically in solution as this additional binding energy lowers its activity. In this work, we estimated the amount of soil pore water that is thermodynamically different from a simple aqueous solution. The quantity of soil pore water with properties different to liquid water was found to systematically increase with increasing clay content. The significance of this is that the grain size and surface area apparently affects the thermodynamic state of water. This implies that current methods to determine the amount of water content, traditionally determined from bulk density or gravimetric water content after drying at 105°C overestimates the amount of free water in a soil especially at higher clay content. Our findings have consequences for biogeochemical processes in soils, e.g. nutrients may be contained in water which is not free which could enhance preservation. From water activity measurements on a set of various soils with 0 to 100 wt-% clay, we can show that 5 to 130 mg H2O per g of soil can generally be considered as unsuitable for microbial respiration. These results may therefore provide a unifying explanation for the grain size dependency of organic matter preservation in sedimentary environments and call for a revised view on the biogeochemical environment in soils and sediments. This could allow a different type of process oriented modelling.

  14. How accurately does output reflect the nature and design of transdisciplinary research programmes?

    Koier, Elizabeth; Horlings, E.

    2014-01-01

    Many of today’s societal problems are wicked problems that require a new, transdisciplinary approach in which knowledge of scientists and stakeholders from different disciplines is integrated. The evaluation of transdisciplinary science requires a multi-method approach. Bibliometric analysis is cons

  15. Understanding the History of Astrology Accurately: Methodological Reflections on Terminology and Anachronism

    Rutkin, H. Daniel

    2015-01-01

    In this essay, I will use two of Roger Bacon’s distinctive phrases—astronomia iudiciaria et operativa and opera et verba sapientium—to build up a picture of his distinctive configuration of the 13thcentury map of knowledge, in which mathematics, perspectiva and astrology are all utterly central. I will then explore how astrology thus configured may be used to explore Bacon’s relation to what we call science, magic and religion, although ...

  16. Urinary Excretion of Liver Type Fatty Acid Binding Protein Accurately Reflects the Degree of Tubulointerstitial Damage

    Yokoyama, Takeshi; Kamijo-Ikemori, Atsuko; Sugaya, Takeshi; Hoshino, Seiko; Yasuda, Takashi; Kimura, Kenjiro

    2009-01-01

    To investigate the relationship between liver-type fatty acid-binding protein (L-FABP), a biomarker of chronic kidney disease, in the kidney and the degree of tubulointerstitial damage, folic acid (FA)-induced nephropathy was studied in a mouse model system. As renal L-FABP is not expressed in wild-type mice, human L-FABP (hL-FABP) transgenic mice were used in this study. hL-FABP is expressed in the renal proximal tubules of the transgenic mice that were injected intraperitoneally with FA in ...

  17. DCP-collected absolute target reflectance signatures assist accurate interpretation of ERTS-1 imagery

    Weber, F. P.

    1973-01-01

    Data collection platforms (DCP's) are being used at a Black Hills, South Dakota, test site (MMC 226A) to record radiometric measurements needed to determine solar and atmospheric parameters that affect ERTS-1 multispectral scanner radiance measurements. A total of 72 channels of analog data transmitted from an unattended ground truth site via three DCP's at least six times a day. The system has operated with only minor problems since September, sending forth daily measurements of biophysical responses and atmospheric conditions. Comparisons of scene radiance data calculated from ERTS images with that measured on the ground show the image-measured values to be 35 percent higher for the green channel and 20 percent higher for the red channel for the same scene targets. Radiance values for channels 6 and 7 are nearly the same from the ground data and from the imagery.

  18. Evaluation of cardiac blood blow, metabolism and sympathetic nerve function in patients with cardiac failure using PET and SPECT. Prognostic diagnosis based on the analysis of aggravating factors of the disease

    Focusing on the failure of energy metabolism, which is assumed to be attributed to the cardiac muscle disorder of a patient with cardiac failure, the characteristics and diagnostic significance of the metabolic disorders of cadiac muscles were investigated in those patients. The diagnostic efficacy of β-methyl iodophenyl pentadecanoic acid (BMIPP) which is a imaging agent for lipid metabolism in the cardiac muscle was assessed in the clinical states of cardiac failure due to pulmonary hypertension. Even if there was a considerable increase in the mean pulmonary arterial pressure (mPAP), the initial accumulation of BMIPP linearly increased, similarly to the increase in the accumulation of MIBI, a blood flow agent. The initial accumulation of BMIPP was thought to reflect a thicken cardiac muscle and/or increased blood flow. Also, its washing-out rate was suggested to be usable as an clinical indicator to estimate the loading of ventricular pressure. (M.N.)

  19. Evaluation of cardiac blood blow, metabolism and sympathetic nerve function in patients with cardiac failure using PET and SPECT. Prognostic diagnosis based on the analysis of aggravating factors of the disease

    Ishida, Yoshio; Shimozu, Junko; Yasumura, Yoshio; Nagatani, Kenzo; Miyatake, Kunio [National Cardiovascular Center, Suita, Osaka (Japan)

    1998-02-01

    Focusing on the failure of energy metabolism, which is assumed to be attributed to the cardiac muscle disorder of a patient with cardiac failure, the characteristics and diagnostic significance of the metabolic disorders of cadiac muscles were investigated in those patients. The diagnostic efficacy of {beta}-methyl iodophenyl pentadecanoic acid (BMIPP) which is a imaging agent for lipid metabolism in the cardiac muscle was assessed in the clinical states of cardiac failure due to pulmonary hypertension. Even if there was a considerable increase in the mean pulmonary arterial pressure (mPAP), the initial accumulation of BMIPP linearly increased, similarly to the increase in the accumulation of MIBI, a blood flow agent. The initial accumulation of BMIPP was thought to reflect a thicken cardiac muscle and/or increased blood flow. Also, its washing-out rate was suggested to be usable as an clinical indicator to estimate the loading of ventricular pressure. (M.N.)

  20. Cardiac Metastasis from Invasive Thymoma Via the Superior Vena Cava: Cardiac MRI Findings

    Cardiac tumors are rare, and metastatic deposits are more common than primary cardiac tumors. We present cardiac magnetic resonance imaging (MRI) findings of a 50-year-old woman with invasive thymoma. Cardiac MRI revealed a heterogeneous, lobulated anterior mediastinal mass invading the superior vena cava and extending to the right atrium. In cine images there was no invasion to the right atrial wall.

  1. Laboratory Building for Accurate Determination of Plutonium

    2008-01-01

    <正>The accurate determination of plutonium is one of the most important assay techniques of nuclear fuel, also the key of the chemical measurement transfer and the base of the nuclear material balance. An

  2. Square and Delta reflection

    Fontanella, Laura; Hayut, Yair

    2016-01-01

    Starting from infinitely many supercompact cardinals, we force a model of ZFC where $\\aleph_{\\omega^2+1}$ satisfies simultaneously a strong principle of reflection, called $\\Delta$-reflection, and a version of the square principle, denoted $\\square(\\aleph_{\\omega^2+1}).$ Thus we show that $\\aleph_{\\omega^2+1}$ can satisfy simultaneously a strong reflection principle and an anti-reflection principle.

  3. Pregnancy as a cardiac stress model

    Chung, Eunhee; Leinwand, Leslie A.

    2014-01-01

    Cardiac hypertrophy occurs during pregnancy as a consequence of both volume overload and hormonal changes. Both pregnancy- and exercise-induced cardiac hypertrophy are generally thought to be similar and physiological. Despite the fact that there are shared transcriptional responses in both forms of cardiac adaptation, pregnancy results in a distinct signature of gene expression in the heart. In some cases, however, pregnancy can induce adverse cardiac events in previously healthy women witho...

  4. Regulation of Cardiac Hypertrophy: the nuclear option

    Kuster, Diederik

    2011-01-01

    textabstractCardiac hypertrophy is the response of the heart to an increased workload. After myocardial infarction (MI) the surviving muscle tissue has to work harder to maintain cardiac output. This sustained increase in workload leads to cardiac hypertrophy. Despite its apparent appropriateness, cardiac hypertrophy is an independent risk factor for the development of heart failure and is therefore called pathological hypertrophy. That hypertrophy is not bad per se, is illustrated by the hyp...

  5. Traumatic Tricuspid Regurgitation Following Cardiac Massage

    Na, Sungwon; Nam, Sang Beom; Lee, Yong Kyung; Oh, Young Jun; Kwak, Young-Lan

    2007-01-01

    We report a 66-yr-old male patient who developed tricuspid regurgitation secondary to internal cardiac massage. After uneventful off-pump coronary artery bypass surgery, the subject experienced cardiac arrest in the intensive care unit. External cardiac massage was initiated and internal cardiac massage was performed eventually. A transesophageal echocardiography revealed avulsion of the anterior papillary muscle and chordae to the anterior leaflet after successful cardiopulmonary resuscitati...

  6. [Cardiac output monitoring by impedance cardiography in cardiac surgery].

    Shimizu, H; Seki, S; Mizuguchi, A; Tsuchida, H; Watanabe, H; Namiki, A

    1990-04-01

    The cardiac output monitoring by impedance cardiography, NCCOM3, was evaluated in adult patients (n = 12) who were subjected to coronary artery bypass grafting. Values of cardiac output measured by impedance cardiography were compared to those by the thermodilution method. Changes of base impedance level used as an index of thoracic fluid volume were also investigated before and after cardiopulmonary bypass (CPB). Correlation coefficient (r) of the values obtained by thermodilution with impedance cardiography was 0.79 and the mean difference was 1.29 +/- 16.9 (SD)% during induction of anesthesia. During the operation, r was 0.83 and the mean difference was -14.6 +/- 18.7%. The measurement by impedance cardiography could be carried out through the operation except when electro-cautery was used. Base impedance level before CPB was significantly lower as compared with that after CPB. There was a negative correlation between the base impedance level and central venous pressure (CVP). No patients showed any signs suggesting lung edema and all the values of CVP, pulmonary artery pressure and blood gas analysis were within normal ranges. From the result of this study, it was concluded that cardiac output monitoring by impedance cardiography was useful in cardiac surgery, but further detailed examinations will be necessary on the relationship between the numerical values of base impedance and the clinical state of the patients. PMID:2362347

  7. Health Literacy Predicts Cardiac Knowledge Gains in Cardiac Rehabilitation Participants

    Mattson, Colleen C.; Rawson, Katherine; Hughes, Joel W.; Waechter, Donna; Rosneck, James

    2015-01-01

    Objective: Health literacy is increasingly recognised as a potentially important patient characteristic related to patient education efforts. We evaluated whether health literacy would predict gains in knowledge after completion of patient education in cardiac rehabilitation. Method: This was a re-post observational analysis study design based on…

  8. Liberating Moral Reflection

    Horell, Harold D.

    2013-01-01

    The author argues that if we are to foster life-giving and liberating moral reflection, we must first liberate moral reflection from distortions; specifically, from the distorting effects of moral insensitivity, destructive moral relativism, and confusions resulting from a failure to understand the dynamics of moral reflection. The author proposes…

  9. Characterization of cardiac quiescence from retrospective cardiac computed tomography using a correlation-based phase-to-phase deviation measure

    Wick, Carson A.; McClellan, James H. [School of Electrical and Computer Engineering, Georgia Institute of Technology, 777 Atlantic Drive Northwest, Atlanta, Georgia 30332 (United States); Arepalli, Chesnal D. [Department of Radiology, University of British Columbia, 3350-950 West 10th Avenue, Vancouver, British Columbia V5Z 4E3 (Canada); Auffermann, William F.; Henry, Travis S. [Department of Radiology and Imaging Sciences, Emory University, Division of Cardiothoracic Imaging, 1364 Clifton Road Northeast, Suite 309, Atlanta, Georgia 30322 (United States); Khosa, Faisal [Department of Radiology and Imaging Sciences, Emory University, Division of Emergency Radiology, 550 Peachtree Street Northeast, Atlanta, Georgia 30308 (United States); Coy, Adam M. [School of Medicine, Emory University, 100 Woodruff Circle, Atlanta, Georgia 30322 (United States); Tridandapani, Srini, E-mail: stridan@emory.edu [Department of Radiology and Imaging Sciences, Emory University, Winship Cancer Institute, 1701 Uppergate Drive Northeast, Suite 5018, Atlanta, Georgia 30322 and School of Electrical and Computer Engineering, Georgia Institute of Technology, 777 Atlantic Drive Northwest, Atlanta, Georgia 30332 (United States)

    2015-02-15

    Purpose: Accurate knowledge of cardiac quiescence is crucial to the performance of many cardiac imaging modalities, including computed tomography coronary angiography (CTCA). To accurately quantify quiescence, a method for detecting the quiescent periods of the heart from retrospective cardiac computed tomography (CT) using a correlation-based, phase-to-phase deviation measure was developed. Methods: Retrospective cardiac CT data were obtained from 20 patients (11 male, 9 female, 33–74 yr) and the left main, left anterior descending, left circumflex, right coronary artery (RCA), and interventricular septum (IVS) were segmented for each phase using a semiautomated technique. Cardiac motion of individual coronary vessels as well as the IVS was calculated using phase-to-phase deviation. As an easily identifiable feature, the IVS was analyzed to assess how well it predicts vessel quiescence. Finally, the diagnostic quality of the reconstructed volumes from the quiescent phases determined using the deviation measure from the vessels in aggregate and the IVS was compared to that from quiescent phases calculated by the CT scanner. Three board-certified radiologists, fellowship-trained in cardiothoracic imaging, graded the diagnostic quality of the reconstructions using a Likert response format: 1 = excellent, 2 = good, 3 = adequate, 4 = nondiagnostic. Results: Systolic and diastolic quiescent periods were identified for each subject from the vessel motion calculated using the phase-to-phase deviation measure. The motion of the IVS was found to be similar to the aggregate vessel (AGG) motion. The diagnostic quality of the coronary vessels for the quiescent phases calculated from the aggregate vessel (P{sub AGG}) and IVS (P{sub IV} {sub S}) deviation signal using the proposed methods was comparable to the quiescent phases calculated by the CT scanner (P{sub CT}). The one exception was the RCA, which improved for P{sub AGG} for 18 of the 20 subjects when compared to P

  10. Characterization of cardiac quiescence from retrospective cardiac computed tomography using a correlation-based phase-to-phase deviation measure

    Purpose: Accurate knowledge of cardiac quiescence is crucial to the performance of many cardiac imaging modalities, including computed tomography coronary angiography (CTCA). To accurately quantify quiescence, a method for detecting the quiescent periods of the heart from retrospective cardiac computed tomography (CT) using a correlation-based, phase-to-phase deviation measure was developed. Methods: Retrospective cardiac CT data were obtained from 20 patients (11 male, 9 female, 33–74 yr) and the left main, left anterior descending, left circumflex, right coronary artery (RCA), and interventricular septum (IVS) were segmented for each phase using a semiautomated technique. Cardiac motion of individual coronary vessels as well as the IVS was calculated using phase-to-phase deviation. As an easily identifiable feature, the IVS was analyzed to assess how well it predicts vessel quiescence. Finally, the diagnostic quality of the reconstructed volumes from the quiescent phases determined using the deviation measure from the vessels in aggregate and the IVS was compared to that from quiescent phases calculated by the CT scanner. Three board-certified radiologists, fellowship-trained in cardiothoracic imaging, graded the diagnostic quality of the reconstructions using a Likert response format: 1 = excellent, 2 = good, 3 = adequate, 4 = nondiagnostic. Results: Systolic and diastolic quiescent periods were identified for each subject from the vessel motion calculated using the phase-to-phase deviation measure. The motion of the IVS was found to be similar to the aggregate vessel (AGG) motion. The diagnostic quality of the coronary vessels for the quiescent phases calculated from the aggregate vessel (PAGG) and IVS (PIV S) deviation signal using the proposed methods was comparable to the quiescent phases calculated by the CT scanner (PCT). The one exception was the RCA, which improved for PAGG for 18 of the 20 subjects when compared to PCT (PCT = 2.48; PAGG = 2.07, p = 0

  11. Accurate LAI retrieval method based on PROBA/CHRIS data

    W. Fan

    2009-11-01

    Full Text Available Leaf area index (LAI is one of the key structural variables in terrestrial vegetation ecosystems. Remote sensing offers a chance to derive LAI in regional scales accurately. Variations of background, atmospheric conditions and the anisotropy of canopy reflectance are three factors that can strongly restrain the accuracy of retrieved LAI. Based on the hybrid canopy reflectance model, a new hyperspectral directional second derivative method (DSD is proposed in this paper. This method can estimate LAI accurately through analyzing the canopy anisotropy. The effect of the background can also be effectively removed. So the inversion precision and the dynamic range can be improved remarkably, which has been proved by numerical simulations. As the derivative method is very sensitive to the random noise, we put forward an innovative filtering approach, by which the data can be de-noised in spectral and spatial dimensions synchronously. It shows that the filtering method can remove the random noise effectively; therefore, the method can be performed to the remotely sensed hyperspectral image. The study region is situated in Zhangye, Gansu Province, China; the hyperspectral and multi-angular image of the study region has been acquired from Compact High-Resolution Imaging Spectrometer/Project for On-Board Autonomy (CHRIS/PROBA, on 4 and 14 June 2008. After the pre-processing procedures, the DSD method was applied, and the retrieve LAI was validated by the ground truth of 11 sites. It shows that by applying innovative filtering method, the new LAI inversion method is accurate and effective.

  12. Childhood cancer survivors: cardiac disease & social outcomes

    E.A.M. Feijen

    2015-01-01

    The thesis is divided in two parts; Cardiac health problems and healthcare consumption & social outcomes in CCS. The general aims of part 1 creates optimal conditions for the evaluation of cardiac events in 5-year childhood cancer survivors, evaluation of the long term risk of cardiac events, and to

  13. MRI of cardiac rhabdomyoma in the fetus

    Kivelitz, Dietmar E.; Muehler, Matthias [Institut fuer Radiologie, Medizinische Fakultaet, Humboldt-Universitaet zu Berlin, Charite, Schumannstrasse 20/21, 10098, Berlin (Germany); Rake, Annett; Chaoui, Rabih [Klinik fuer Gynaekologie und Geburtshilfe, Medizinische Fakultaet, Humboldt-Universitaet zu Berlin, Charite, Schumannstrasse 20/21, 10098, Berlin (Germany); Scheer, Ianina [Klinik fuer Strahlenheilkunde, Abteilung Paediatrische Radiologie, Medizinische Fakultaet, Humboldt-Universitaet zu Berlin, Charite, Schumannstrasse 20/21, 10098, Berlin (Germany)

    2004-08-01

    Primary cardiac tumors are rarely diagnosed in utero and are usually seen on prenatal echocardiography. Cardiac rhabdomyomata can be associated with tuberous sclerosis. Prenatal MRI can be performed to assess associated malformations. This case report illustrates the ability of fetal MRI to image cardiac rhabdomyata and compares it with prenatal and postnatal echocardiography. (orig.)

  14. Telocytes in exercise-induced cardiac growth.

    Xiao, Junjie; Chen, Ping; Qu, Yi; Yu, Pujiao; Yao, Jianhua; Wang, Hongbao; Fu, Siyi; Bei, Yihua; Chen, Yan; Che, Lin; Xu, Jiahong

    2016-05-01

    Exercise can induce physiological cardiac growth, which is featured by enlarged cardiomyocyte cell size and formation of new cardiomyocytes. Telocytes (TCs) are a recently identified distinct interstitial cell type, existing in many tissues and organs including heart. TCs have been shown to form a tandem with cardiac stem/progenitor cells in cardiac stem cell niches, participating in cardiac regeneration and repair. Although exercise-induced cardiac growth has been confirmed as an important way to promote cardiac regeneration and repair, the response of cardiac TCs to exercise is still unclear. In this study, 4 weeks of swimming training was used to induce robust healthy cardiac growth. Exercise can induce an increase in cardiomyocyte cell size and formation of new cardiomyocytes as determined by Wheat Germ Lectin and EdU staining respectively. TCs were identified by three immunofluorescence stainings including double labelling for CD34/vimentin, CD34/platelet-derived growth factor (PDGF) receptor-α and CD34/PDGF receptor-β. We found that cardiac TCs were significantly increased in exercised heart, suggesting that TCs might help control the activity of cardiac stem/progenitor cells, cardiomyocytes or endothelial cells. Adding cardiac TCs might help promote cardiac regeneration and renewal. PMID:26987685

  15. Cardiac, Skeletal, and smooth muscle mitochondrial respiration

    Park, Song-Young; Gifford, Jayson R; Andtbacka, Robert H I; Hyngstrom, John R; Garten, Ryan S; Diakos, Nikolaos A; Ives, Stephen J; Dela, Flemming; Larsen, Steen; Drakos, Stavros; Richardson, Russell S

    2014-01-01

    Unlike cardiac and skeletal muscle, little is known about vascular smooth muscle mitochondrial function. Therefore, this study examined mitochondrial respiratory rates in the smooth muscle of healthy human feed arteries and compared with that of healthy cardiac and skeletal muscle. Cardiac, skele...

  16. Technique for producing cardiac radionuclide motion images

    Sequential frames of different portions of the cardiac cycle are gated into a minicomputer by using an EKG signal recorded onto digital tape simultaneously with imaging information. Serial display of these frames on the computer oscilloscope or projection of 35-mm half frames of these images provides a cardiac motion image with information content adequate for qualitatively assessing cardiac motion. (U.S.)

  17. Regulation of Cardiac Hypertrophy: the nuclear option

    D.W.D. Kuster (Diederik)

    2011-01-01

    textabstractCardiac hypertrophy is the response of the heart to an increased workload. After myocardial infarction (MI) the surviving muscle tissue has to work harder to maintain cardiac output. This sustained increase in workload leads to cardiac hypertrophy. Despite its apparent appropriateness, c

  18. Italian survey on cardiac rehabilitation and secondary prevention after cardiac revascularization: ICAROS study. A survey from the Italian cardiac rehabilitation network: rationale and design.

    Griffo, Raffaele; Fattirolli, Francesco; Temporelli, Pier Luigi; Tramarin, Roberto

    2008-09-01

    In this paper, the Italian Association for Cardiac Prevention and Rehabilitation (GICR) presents the rationale and design of the "Italian survey on CArdiac RehabilitatiOn and Secondary prevention after cardiac revascularization (ICAROS)". The survey is a prospective, longitudinal, multicentric survey, with a on-line web-based data collection. Its design corresponds to the survey's goal, i.e. to describe accurately in the Italian cardiological setting, through a representative number of cardiac rehabilitation centers belonging to the GICR national network, the characteristics, content and effects in the medium term of cardiac rehabilitation (CRP) inpatient or outpatient programs offered to patients after coronary artery bypass (CABG) or percutaneous revascularization (PTCA). The primary aims of the study are: a) to define the principal clinical characteristics of patients who have undergone PTCA or CABG and have been admitted to a CRP program; b) to identify the components of the CRP programs in terms of diagnostic procedures and assessment tests performed, treatments administered, educational programs and physical exercise interventions employed; c) to identify and analyze drug treatments prescribed at discharge from the acute facility and those prescribed at the end of the CRP program; d) to verify the clinical outcome during the course of the CRP program and at 6 months and 1 year after the end of the post-acute CRP program, as well as patients' adherence to the prescribed pharmacological therapy and to the recommended life styles, and the achievement and maintenance of the targets in relation to the modifiable risk factors; e) to define the consumption of major healthcare resources (major cardiac events, hospital re-admission, emergency care access, specialist visits) during the first year following a CRP program. The survey population will consist of all patients consecutively discharged in the period November 3-30, 2008 at the end of an inpatient, day

  19. Reflection Positive Doubles

    Jaffe, Arthur

    2016-01-01

    Here we introduce reflection positive doubles, a general framework for reflection positivity, covering a wide variety of systems in statistical physics and quantum field theory. These systems may be bosonic, fermionic, or parafermionic in nature. Within the framework of reflection positive doubles, we give necessary and sufficient conditions for reflection positivity. We use a reflection-invariant cone to implement our construction. Our characterization allows for a direct interpretation in terms of coupling constants, making it easy to check in concrete situations. We illustrate our methods with numerous examples.

  20. Genetic counseling and cardiac care in predictively tested hypertrophic cardiomyopathy mutation carriers: The patients' perspective

    Christiaans, Imke; Van Langen, Irene M.; Birnie, Erwin; Bonsel, Gouke J.; Wilde, Arthur A. M.; Smets, Ellen M. A.

    2009-01-01

    Hypertrophic cardiomyopathy (HCM) is a common hereditary heart disease associated with sudden cardiac death. Predictive genetic counseling and testing are performed using adapted Huntington guidelines, that is, psychosocial care and time for reflection are not obligatory and the test result can be d

  1. Genetic counseling and cardiac care in predictively tested hypertrophic cardiomyopathy mutation carriers: The patients' perspective

    I. Christiaans; I.M. van Langen; E. Birnie; G.J. Bonsel; A.A.M. Wilde; E.M.A. Smets

    2009-01-01

    Hypertrophic cardiomyopathy (HCM) is a common hereditary heart disease associated with sudden cardiac death. predictive genetic counseling and testing are performed using adapted Huntington guidelines, that is, psychosocial care and time for reflection are not obligatory and the test result can be d

  2. Response to cardiac resynchronization therapy

    Versteeg, Henneke; Schiffer, Angélique A; Widdershoven, Jos W; Meine, Mathias M; Doevendans, Pieter A; Pedersen, Susanne S.

    2009-01-01

    Cardiac resynchronization therapy (CRT) is a promising treatment for a subgroup of patients with advanced congestive heart failure and a prolonged QRS interval. Despite the majority of patients benefiting from CRT, 10-40% of patients do not respond to this treatment and are labeled as nonresponders...

  3. Rejection in the cardiac transplant

    Standard chest radiography remains the most frequent applied method for monitoring post surgical cardiac transplant patients. Evidence suggests that after the 1st month cardiac enlargement is indeed a useful indicator of rejection, sometimes being caused by pericardial effusion and/or changes in left ventricular mass. Opportunistic infections, either pulmonary lesions or mediastinal abscesses, as well as malignant tumours may all occur and require evaluation or exclusion. Conventional computed transmission tomography is an excellent technique for surveying the entire thorax relatively non-invasively and is recommended whenever pulmonary, cardiac or mediastinal changes are unexplained. Coronary arteriography with or without digital subtraction remains the definitive method for examining the coronary arteries. Left ventricular function can be evaluated with either angiography or other non-invasive methods including such techniques as echocardiography and nuclear medicine. More recently monoclonal antibody labels for antimyosin show promise for identifying rejection. Ultrafast CT scanning is now available in a number of centres. It allows millisecond cross-sectional cine-tomography of the heart as well as of the whole chest, and also provides 3-D quantitative analyses of end-diastolic and systolic function including regional wall thickening dynamics and estimations of myocardial mass. Right, as well as left-sided cardiac chambers, are demonstrated routinely during the same ultrafast CT procedure. MRI, like ultrafast CT, is a new technique still being explored. MRI as well as MR spectroscopy are regarded as diagnostic radiology procedures. (author). 32 refs.; 3 figs.; 3 tabs

  4. Cardiac functional analysis with MRI

    Cardiovascular diseases (CVD) are among the leading causes of death worldwide. Even in the 21st century CVD will still be the most frequent cause of morbidity and mortality. Precise evaluation of cardiac function is therefore mandatory for therapy planning and monitoring. In this article the contribution of MRI-based analysis of cardiac function will be addressed. Nowadays cine-MRI is considered as the standard of reference (SOR) in cardiac functional analysis. ECG-triggered steady-state free precession (SSFP) sequences are mainly used as they stand out due to short acquisition times and excellent contrast between the myocardium and the ventricular cavity. An indispensible requirement for cardiac functional analysis is an exact planning of the examination and based on that the coverage of the whole ventricle in short axial slices. By means of dedicated post-processing software, manual or semi-automatic segmentation of the endocardial and epicardial contours is necessary for functional analysis. In this way end-diastolic volume (EDV), end-systolic volume (ESV) and the ejection fraction (EF) are defined and regional wall motion abnormalities (RWMA) can be detected. (orig.)

  5. Molecular therapies for cardiac arrhythmias

    G.J.J. Boink

    2013-01-01

    Despite the ongoing advances in pharmacology, devices and surgical approaches to treat heart rhythm disturbances, arrhythmias are still a significant cause of death and morbidity. With the introduction of gene and cell therapy, new avenues have arrived for the local modulation of cardiac disease. Th

  6. The cardiac patient in Ramadan.

    Chamsi-Pasha, Majed; Chamsi-Pasha, Hassan

    2016-01-01

    Ramadan is one of the five fundamental pillars of Islam. During this month, the majority of the 1.6 billion Muslims worldwide observe an absolute fast from dawn to sunset without any drink or food. Our review shows that the impact of fasting during Ramadan on patients with stable cardiac disease is minimal and does not lead to any increase in acute events. Most patients with the stable cardiac disease can fast safely. Most of the drug doses and their regimen are easily manageable during this month and may need not to be changed. Ramadan fasting is a healthy nonpharmacological means for improving cardiovascular risk factors. Most of the Muslims, who suffer from chronic diseases, insist on fasting Ramadan despite being exempted by religion. The Holy Quran specifically exempts the sick from fasting. This is particularly relevant if fasting worsens one's illness or delays recovery. Patients with unstable angina, recent myocardial infarction, uncontrolled hypertension, decompensated heart failure, recent cardiac intervention or cardiac surgery or any debilitating diseases should avoid fasting. PMID:27144139

  7. Cardiac pacemakers and nuclear batteries

    Following the introduction giving the indications for cardiac pacemaker therapy with special regard to the use of pacemakers powered by nuclear batteries, reference is made to the resulting radiation exposure of the patient. The activities of the Federal Health Office in this field such as recommendations and surveys including the entire Federal Republic are outlined. (orig.)

  8. CARDIAC TRANSPLANTATION: AN ANESTHETIC CHALLENGE

    Premalatha; Jayaraman,

    2014-01-01

    : Heart transplantation has emerged as the definitive therapy for patients with end-stage cardiomyopathy. The two most common forms of cardiac disease that lead to transplantation are ischemic cardiomyopathy and dilated cardiomyopathy, which together comprise approximately 90% of cases. The other less common forms of heart disease include viral cardiomyopathy, infiltrative cardiomyopathy, postpartum cardiomyopathy, valvular heart disease and congenital heart disease

  9. Epidural analgesia for cardiac surgery

    V. Svircevic; M.M. Passier; A.P. Nierich; D. van Dijk; C.J. Kalkman; G.J. van der Heijden

    2013-01-01

    Background A combination of general anaesthesia (GA) with thoracic epidural analgesia (TEA) may have a beneficial effect on clinical outcomes by reducing the risk of perioperative complications after cardiac surgery. Objectives The objective of this review was to determine the impact of perioperativ

  10. Historical highlights in cardiac pacing.

    Geddes, L A

    1990-01-01

    The benchmarks in cardiac pacing are identified, beginning with F. Steiner (1871), who rhythmically stimulated the chloroform-arrested hearts of 3 horses, 1 donkey, 10 dogs, 14 cats, and 8 rabbits. The chloroform-arrested heart in human subjects was paced by T. Greene in the following year (1872) in the UK. In 1882, H. Ziemssen in Germany applied cardiac pacing to a 42-year old woman who had a large defect in the anterior left chest wall subsequent to resection of an enchondroma. Intentional cardiac pacing did not occur until 1932, when A.A. Hyman in the US demonstrated that cardiac pacing could be clinically practical. Hyman made a batteryless pacemaker for delivery in induction shock stimuli (60-120/min) to the atria. His pacemaker was powered by a hand-wound, spring-driven generator which provided 6 min of pacemaking without rewinding. Closed-chest ventricular pacing was introduced in the US in 1952 by P.M. Zoll et al. Zoll (1956) also introduced closed-chest ventricular defibrillation. W.L. Weirich et al. (1958) demonstrated that direct-heart stimulation in closed-chest patients could be achieved with slender wire electrodes. S. Furman and J.B. Schwedel (1959) developed a monopolar catheter electrode for ventricular pacing in man. In the same year, W. Greatbatch and W.M. Chardack developed the implantable pacemaker. PMID:18238328

  11. Effect of Exercise and Vitamin E on Cardiac Troponin Alterations in Myocardium and Serum of Rats after Stressful Intense Exercise

    N.S. AL-Sowyan

    2010-01-01

    Increased concentrations of biomarkers reflecting myocardial stress such as cardiac troponin have been observed following strenuous exercise. The aim of this study was to determine whether the stress of forced exercise would result in injury to the myocardium. The effects of stress induced by short bout strenuous exercise and long term exercise on serum, cardiac and skeletal muscle troponin, also blood glucose and insulin were measured. Moreover, to determine whether vitamin E supplementation...

  12. Invariant Image Watermarking Using Accurate Zernike Moments

    Ismail A. Ismail

    2010-01-01

    Full Text Available problem statement: Digital image watermarking is the most popular method for image authentication, copyright protection and content description. Zernike moments are the most widely used moments in image processing and pattern recognition. The magnitudes of Zernike moments are rotation invariant so they can be used just as a watermark signal or be further modified to carry embedded data. The computed Zernike moments in Cartesian coordinate are not accurate due to geometrical and numerical error. Approach: In this study, we employed a robust image-watermarking algorithm using accurate Zernike moments. These moments are computed in polar coordinate, where both approximation and geometric errors are removed. Accurate Zernike moments are used in image watermarking and proved to be robust against different kind of geometric attacks. The performance of the proposed algorithm is evaluated using standard images. Results: Experimental results show that, accurate Zernike moments achieve higher degree of robustness than those approximated ones against rotation, scaling, flipping, shearing and affine transformation. Conclusion: By computing accurate Zernike moments, the embedded bits watermark can be extracted at low error rate.

  13. Cardiac arrest: resuscitation and reperfusion.

    Patil, Kaustubha D; Halperin, Henry R; Becker, Lance B

    2015-06-01

    The modern treatment of cardiac arrest is an increasingly complex medical procedure with a rapidly changing array of therapeutic approaches designed to restore life to victims of sudden death. The 2 primary goals of providing artificial circulation and defibrillation to halt ventricular fibrillation remain of paramount importance for saving lives. They have undergone significant improvements in technology and dissemination into the community subsequent to their establishment 60 years ago. The evolution of artificial circulation includes efforts to optimize manual cardiopulmonary resuscitation, external mechanical cardiopulmonary resuscitation devices designed to augment circulation, and may soon advance further into the rapid deployment of specially designed internal emergency cardiopulmonary bypass devices. The development of defibrillation technologies has progressed from bulky internal defibrillators paddles applied directly to the heart, to manually controlled external defibrillators, to automatic external defibrillators that can now be obtained over-the-counter for widespread use in the community or home. But the modern treatment of cardiac arrest now involves more than merely providing circulation and defibrillation. As suggested by a 3-phase model of treatment, newer approaches targeting patients who have had a more prolonged cardiac arrest include treatment of the metabolic phase of cardiac arrest with therapeutic hypothermia, agents to treat or prevent reperfusion injury, new strategies specifically focused on pulseless electric activity, which is the presenting rhythm in at least one third of cardiac arrests, and aggressive post resuscitation care. There are discoveries at the cellular and molecular level about ischemia and reperfusion pathobiology that may be translated into future new therapies. On the near horizon is the combination of advanced cardiopulmonary bypass plus a cocktail of multiple agents targeted at restoration of normal metabolism and

  14. A robust and accurate formulation of molecular and colloidal electrostatics

    Sun, Qiang; Klaseboer, Evert; Chan, Derek Y. C.

    2016-08-01

    This paper presents a re-formulation of the boundary integral method for the Debye-Hückel model of molecular and colloidal electrostatics that removes the mathematical singularities that have to date been accepted as an intrinsic part of the conventional boundary integral equation method. The essence of the present boundary regularized integral equation formulation consists of subtracting a known solution from the conventional boundary integral method in such a way as to cancel out the singularities associated with the Green's function. This approach better reflects the non-singular physical behavior of the systems on boundaries with the benefits of the following: (i) the surface integrals can be evaluated accurately using quadrature without any need to devise special numerical integration procedures, (ii) being able to use quadratic or spline function surface elements to represent the surface more accurately and the variation of the functions within each element is represented to a consistent level of precision by appropriate interpolation functions, (iii) being able to calculate electric fields, even at boundaries, accurately and directly from the potential without having to solve hypersingular integral equations and this imparts high precision in calculating the Maxwell stress tensor and consequently, intermolecular or colloidal forces, (iv) a reliable way to handle geometric configurations in which different parts of the boundary can be very close together without being affected by numerical instabilities, therefore potentials, fields, and forces between surfaces can be found accurately at surface separations down to near contact, and (v) having the simplicity of a formulation that does not require complex algorithms to handle singularities will result in significant savings in coding effort and in the reduction of opportunities for coding errors. These advantages are illustrated using examples drawn from molecular and colloidal electrostatics.

  15. SAW reflection and scattering by electrodes

    WANG Wei-biao; HAN Tao; ZHANG Xiao-dong; WU Hao-dong; SHUI Yong-an

    2005-01-01

    A rigorous analysis of surface acoustic wave (SAW) reflection and scattering by electrodes is of paramount importance in the design of SAW identification tags and sensors. In this paper, a new method based on Green's function concept is used to study reflection and scattering coefficients. By this method the reflection coefficient with its phase angle, transmission coefficient, and bulk wave scattering coefficient, can be obtained rapidly and accurately. To get precise result, the influence of static charge must be taken into account. In the work, we successfully cancelled out the effect of static charge and the validity of the results was checked. As an example, the reflection, transmission and scattering coefficients ora single grounded electrode on 128°YX LiNbO3 is shown.

  16. Effect of dose-reduced scan protocols on cardiac coronary image quality with 64-row MDCT: A cardiac phantom study

    Objective: To evaluate the feasibility of using relative low-dose scan protocols in coronary imaging with 64-row MDCT. Materials and methods: A pulsating cardiac phantom was used to simulate coronary arteries of two sizes (3 and 5 mm in diameter) with three stenosis degrees (25, 50 and 75%) at 55 bpm heart rate. Cardiac scans were performed on a 64-row MDCT scanner (GE LightSpeed VCT) with rotation time of 350 ms and pitch of 0.2 under six different scan protocols: 120 kV/650 mA, 1137.5 mAs (effective) (CTDIvol 121.69 mGy), 120 kV/550 mA, 962.5 mAs (CTDIvol 102.96 mGy), 120 kV/450 mA, 787.5 mAs (CTDIvol 84.24 mGy), 120 kV/350 mA, 612.5 mAs (CTDIvol 65.52 mGy), 100 kV/590 mA, 1032.5 mAs (CTDIvol 65.17 mGy) and 140 kV/390 mA, 682.5 mAs (CTDIvol 102.22 mGy). The simulative coronary arteries were filled with contrast media to reach 300 HU in the lumen. Background noise was measured to describe the basic image quality accordingly. CNR, SNR and contour sharpness represented in slope of CT density curve was calculated as well. Measured stenosis area and rates, described by the percentage area of stenosis on the cross-section images were also calculated. Results: The corresponding image noise levels described in standard deviation of background signals varied with radiation dose, CNR and SNR mainly varied with tube current. The contour sharpness, which can reflect actual spatial resolution, is affected mainly by tube voltage. The first five protocols depicted obviously steeper curves than the sixth one (P 0.05). As for evaluation on 50 and 75% stenosis, there was no significant difference between the first two protocols, and between the second two protocols as well. However, significant difference presented between these two groups (P > 0.05). When comparing the groups with similar radiation dose, protocols with lower tube voltage gain more accuracy in representing stenosis area and rate. Conclusion: Dose level and corresponding image quality is relevant to the accuracy of

  17. Cavity ring-down technique for measurement of reflectivity of high reflectivity mirrors with high accuracy

    G Sridhar; Sandeep K Agarwalla; Sunita Singh; L M Gantayet

    2010-12-01

    A simple, accurate and reliable method for measuring the reflectivity of laser-grade mirrors ( > 99.5 %) based on cavity ring-down (CRD) technique has been success-fully demonstrated in our laboratory using a pulsed Nd:YAG laser. A fast photomultiplier tube with an oscilloscope was used to detect and analyse the CRD signal. The cavity decay times were measured for three cavities formed by a combination of three mirror pairs. The absolute reflectivities 1, 2, 3 were determined to be 99.94%, 99.63%, 99.52% at normal incidence. The reflectivity of mirrors is measured to an accuracy of 0.01%.

  18. Automatic cardiac gating of small-animal PET from list-mode data

    Herraiz, J.L.; Udias, J.M. [Universidad Complutense de Madrid Univ. (Spain). Grupo de Fisica Nuclear; Vaquero, J.J.; Desco, M. [Universidad Carlos III de Madrid (Spain). Dept. de Bioingenieria e Ingenieria Aeroespacial; Cusso, L. [Hospital General Universitario Gregorio Maranon, Madrid (Spain). Unidad de Medicina y Cirugia Experimental

    2011-07-01

    This work presents a method to obtain automatically the cardiac gating signal in a PET study of rats, by employing the variation with time of the counts in the cardiac region, that can be extracted from list-mode data. In an initial step, the cardiac region is identified in the image space by backward-projecting a small fraction of the acquired data and studying the variation with time of the counts in each voxel inside said region, with frequencies within 2 and 8 Hz. The region obtained corresponds accurately to the left-ventricle of the heart of the rat. In a second step, the lines-of-response (LORs) connected with this region are found by forward-projecting this region. The time variation of the number of counts in these LORs contains the cardiac motion information that we want to extract. This variation of counts with time is band-pass filtered to reduce noise, and the time signal so obtained is used to create the gating signal. The result was compared with a cardiac gating signal obtained from an ECG acquired simultaneously to the PET study. Reconstructed gated images obtained from both gating information are similar. The method proposed demonstrates that valid cardiac gating signals can be obtained for rats from PET list-mode data. (orig.)

  19. Acquisition and automated 3-D segmentation of respiratory/cardiac-gated PET transmission images

    To evaluate the impact of respiratory motion on attenuation correction of cardiac PET data, we acquired and automatically segmented gated transmission data for a dog breathing on its own under gas anesthesia. Data were acquired for 20 min on a CTI/Siemens ECAT EXACT HR (47-slice) scanner configured for 12 gates in a static study, Two respiratory gates were obtained using data from a pneumatic bellows placed around the dog's chest, in conjunction with 6 cardiac gates from standard EKG gating. Both signals were directed to a LabVIEW-controlled Macintosh, which translated them into one of 12 gate addresses. The respiratory gating threshold was placed near end-expiration to acquire 6 cardiac-gated datasets at end-expiration and 6 cardiac-gated datasets during breaths. Breaths occurred about once every 10 sec and lasted about 1-1.5 sec. For each respiratory gate, data were summed over cardiac gates and torso and lung surfaces were segmented automatically using a differential 3-D edge detection algorithm. Three-dimensional visualizations showed that lung surfaces adjacent to the heart translated 9 mm inferiorly during breaths. Our results suggest that respiration-compensated attenuation correction is feasible with a modest amount of gated transmission data and is necessary for accurate quantitation of high-resolution gated cardiac PET data

  20. Clinical application of dual gate Doppler in evaluating cardiac function and synchronization%双多普勒同步取样技术评价心脏功能及同步性的临床应用

    周燕翔; 冷倩倩; 郭瑞强

    2016-01-01

    Dual gate Doppler is a newly-developed technology in recent years, which can synchronously place two sampling volume. Based on its advantages,dual gate Doppler can not only measure indexes which reflect cardiac function more accurately than conventional Doppler,but also provide a more convenient method to evaluate the cardiac synchronization. And it can reflect the myocardial tissue motions and hemodynamic changes in the heart cavity timely,intuitively and fast,offer a new perspective to quantitatively estimate the coupling relations between wall mechanics and heart cavity fluid mechanics.This article aims to introduce the applications of dual gate Doppler in evaluating cardiac function and synchronization.%双多普勒同步取样技术是近年来出现的新技术;其可以在同一切面同步放置两个取样容积,不仅可以更准确地反映心脏功能,而且可以更简便地评价心脏同步性。同时,双多普勒技术可以实时、直观、快速地显示心肌组织运动与心腔内血流动力学的变化,为定量评价室壁运动力学与心腔内流体力学的耦联关系提供了新视角。本文就双多普勒技术在评价心脏功能及同步性等方面的应用作一综述。

  1. Media for Reflection

    Knudsen, Morten

    2016-01-01

    This article develops the concept media for reflection in the interest of conceptualizing the interpretative frames that enable and limit reflection in management and leadership education. The concept ‘media for reflection’ allows us to conceptualize the social and cultural mediation of reflection...... without reducing reflection to an effect of the social structures and cultural norms in which it is embedded. Based on the developed theoretical framework, this article analyses how a renaissance ‘mirror for princes’ and contemporary research-based management education mediate reflection. The content of...... the mediations is analysed as well as the societal and organizational background. Furthermore, the means by which the two media enable and limit reflection in different ways is compared. Finally, the article discusses possible implications of the analysis in terms of management and leadership...

  2. Clinical application of EBCT in the diagnosis of cardiac neoplasms

    Objective: To probe the clinical utilization of electron beam CT (EBCT) in the diagnosis of cardiac neoplasms. Methods: Between July 1995 and Feb 1999. EBCT was performed in 12024 patients in our hospital. 40 (0.33%) patients were diagnosed as cardiac neoplasms. Retrospective analysis of 22 patients confirmed by operation, autopsy or follow-up was done. In this group, there were 13 males and 9 females, age ranged from 5 months to 72 years old (averaged 41.9 years). 17 patients had both contrast single slice mode (contrast SSM) and movie mode, 3 patients only SSM, 1 patient movie mode and 1 patient plain SSM. Results: Accurate localization and quantitative diagnoses were made in all the 22 patients and correct histopathological diagnosis was made in 10 patients with myxoma. EBCT provided characteristic clues to proper histopathological determination in 6 of the 7 patients with non-myxomatous benign neoplasms. In the 5 patients with malignant masses, 4 patients acquired distinct histopathological classifications, and involvement of the adjacent anatomic structures was revealed. Conclusion: Because of excellent temporal, spatial and density resolution, EBCT has not only high accuracy in the diagnosis of myxoma, but also possesses advantage superior to echocardiography in the definition of non-myxomatous benign and malignant neoplasms, which are difficult to diagnose histopathologically using echocardiography. EBCT is also valuable for assessment of involvement of neighbouring organs. In the diagnosis of cardiac neoplasm without specific features, this method is limited and difficult

  3. A Case Report on Upper Extremity Pain of Cardiac Origin

    Turgay Altınbilek

    2016-08-01

    Full Text Available Upper extremity pain can originate from the musculoskeletal system, or be a reflection of problems originating from various organs. Therefore, it is highly important to perform a detailed clinical evaluation on patients during differential diagnosis. In this case report, we present a 61 year-old male patient who was admitted with pain in both upper extremities and the upper back that presumed to be of cardiac origin following our clinical evaluations. The patient was referred to the cardiology department, where he was diagnosed with coronary heart disease. The patient’s complaints of pain were fully resolved through the application of an intracoronary stent.

  4. Reflection in professional practice

    Hetzner, Stefanie Bianca

    2014-01-01

    The purpose of this thesis is to contribute to the research on professional learning through reflective practice. The main goal is to examine—against the backdrop of workplace changes and errors—individual and contextual factors that are theoretically assumed to influence reflection in the context of professional work. Reflective practice is defined as a retrospective but future- and goal-oriented cognitive-affective process that basically involves (a) the awareness and review of incident...

  5. Cardiac troponin: an emerging cardiac biomarker in animal health

    Vishal V. Undhad

    Full Text Available Analysis of cardiac troponin I (cTn I and T (cTnT are considered the “gold standard” for the non-invasive diagnosis of myocardial injury in human and animals. It has replaced traditionally used cardiac biomarkers such as myoglobin, lactate dehydrogenase (LDH, creatine kinase (CK and CK-MB due to its high sensitivity and specificity for the detection of myocardial injury. Cardiac troponins are proteins that control the calcium-mediated interaction between actin and myosin, allowing contraction at the sarcomere level. Concentration of the cTn can be correlated microscopic lesion and loss of immunolabeling in myocardium damage. Troponin concentration remains elevated in blood for 1-2wks so that wide window is available for diagnosis of myocardial damage. The cTn test has >95% specificity and sensitivity and test is less time consuming (10 to 15 minutes and less costly (INR 200 to INR 500. [Vet. World 2012; 5(8.000: 508-511

  6. Non-rigid dual respiratory and cardiac motion correction methods after, during, and before image reconstruction for 4D cardiac PET

    Feng, Tao; Wang, Jizhe; Fung, George; Tsui, Benjamin

    2016-01-01

    Respiratory motion (RM) and cardiac motion (CM) degrade the quality and resolution in cardiac PET scans. We have developed non-rigid motion estimation methods to estimate both RM and CM based on 4D cardiac gated PET data alone, and compensate the dual respiratory and cardiac (R&C) motions after (MCAR), during (MCDR), and before (MCBR) image reconstruction. In all three R&C motion correction methods, attenuation-activity mismatch effect was modeled by using transformed attenuation maps using the estimated RM. The difference of using activity preserving and non-activity preserving models in R&C correction was also studied. Realistic Monte Carlo simulated 4D cardiac PET data using the 4D XCAT phantom and accurate models of the scanner design parameters and performance characteristics at different noise levels were employed as the known truth and for method development and evaluation. Results from the simulation study suggested that all three dual R&C motion correction methods provide substantial improvement in the quality of 4D cardiac gated PET images as compared with no motion correction. Specifically, the MCDR method yields the best performance for all different noise levels compared with the MCAR and MCBR methods. While MCBR reduces computational time dramatically but the resultant 4D cardiac gated PET images has overall inferior image quality when compared to that from the MCAR and MCDR approaches in the ‘almost’ noise free case. Also, the MCBR method has better noise handling properties when compared with MCAR and provides better quantitative results in high noise cases. When the goal is to reduce scan time or patient radiation dose, MCDR and MCBR provide a good compromise between image quality and computational times.

  7. Accurate atomic data for industrial plasma applications

    Griesmann, U.; Bridges, J.M.; Roberts, J.R.; Wiese, W.L.; Fuhr, J.R. [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

    1997-12-31

    Reliable branching fraction, transition probability and transition wavelength data for radiative dipole transitions of atoms and ions in plasma are important in many industrial applications. Optical plasma diagnostics and modeling of the radiation transport in electrical discharge plasmas (e.g. in electrical lighting) depend on accurate basic atomic data. NIST has an ongoing experimental research program to provide accurate atomic data for radiative transitions. The new NIST UV-vis-IR high resolution Fourier transform spectrometer has become an excellent tool for accurate and efficient measurements of numerous transition wavelengths and branching fractions in a wide wavelength range. Recently, the authors have also begun to employ photon counting techniques for very accurate measurements of branching fractions of weaker spectral lines with the intent to improve the overall accuracy for experimental branching fractions to better than 5%. They have now completed their studies of transition probabilities of Ne I and Ne II. The results agree well with recent calculations and for the first time provide reliable transition probabilities for many weak intercombination lines.

  8. More accurate picture of human body organs

    Computerized tomography and nucler magnetic resonance tomography (NMRT) are revolutionary contributions to radiodiagnosis because they allow to obtain a more accurate image of human body organs. The principles are described of both methods. Attention is mainly devoted to NMRT which has clinically only been used for three years. It does not burden the organism with ionizing radiation. (Ha)

  9. Cardiac Iodine-123 metaiodobenzylguanidine (123I-MIBG) scintigraphy parameter predicts cardiac and cerebrovascular events in type 2 diabetic patients without structural heart disease

    Cardiac iodine-123 metaiodobenzylguanidine (123I-MIBG) scintigraphy is an established method of assessment of cardiovascular sympathetic function. The aim of the present study was to investigate the long-term cardiovascular predictive value of cardiac 123I-MIBG scintigraphy parameters in Japanese type 2 diabetic patients without structural heart disease. Cardiac 123I-MIBG scintigraphy in 108 patients with type 2 diabetes who did not have structural heart disease, was evaluated. The washout rate (WR) was considered enhanced if it was ≥40%. Accurate follow-up information for 4.6 years was obtained in 54 enhanced WR patients (27 male; mean age, 61±11 years) and in 54 sex- and age-matched preserved WR patients (27 male; mean age, 61±10 years). Major adverse cardiac and cerebrovascular events (MACCE) were investigated. During follow-up, 10 enhanced WR patients developed MACCE including cardiac death, coronary revascularization, stroke, and congestive heart failure, while MACCE occurred in only 3 male patients. The Kaplan-Meier curves indicated that enhanced WR patients had higher incidence of MACCE than those with preserved WR (P123I-MIBG scintigraphy at baseline has long-term cardiovascular predictive value in Japanese patients with type 2 diabetes without structural heart disease. (author)

  10. Cardiac Arrest in a Heart Transplant Patient Receiving Dexmedetomidine During Cardiac Catheterization.

    Schwartz, Lawrence Israel; Miyamoto, Shelley D; Stenquist, Scott; Twite, Mark David

    2016-06-01

    Dexmedetomidine is an α-2 agonist with a sedative and cardiopulmonary profile that makes it an attractive anesthetic in pediatric cardiac patients. Cardiac transplant patients may suffer from acute cellular rejection of the cardiac conduction system and, therefore, are at an increased risk of the electrophysiological effect of dexmedetomidine. We present such a patient who had a cardiac arrest while receiving dexmedetomidine during cardiac catheterization. Because acute cellular rejection of the cardiac conduction system is difficult to diagnose, dexmedetomidine should be used with caution in pediatric heart transplant patients. PMID:26721807

  11. Functional Relevance of Coronary Artery Disease by Cardiac Magnetic Resonance and Cardiac Computed Tomography: Myocardial Perfusion and Fractional Flow Reserve

    Gianluca Pontone

    2015-01-01

    Full Text Available Coronary artery disease (CAD is one of the leading causes of morbidity and mortality and it is responsible for an increasing resource burden. The identification of patients at high risk for adverse events is crucial to select those who will receive the greatest benefit from revascularization. To this aim, several non-invasive functional imaging modalities are usually used as gatekeeper to invasive coronary angiography, but the diagnostic yield of elective invasive coronary angiography remains unfortunately low. Stress myocardial perfusion imaging by cardiac magnetic resonance (stress-CMR has emerged as an accurate technique for diagnosis and prognostic stratification of the patients with known or suspected CAD thanks to high spatial and temporal resolution, absence of ionizing radiation, and the multiparametric value including the assessment of cardiac anatomy, function, and viability. On the other side, cardiac computed tomography (CCT has emerged as unique technique providing coronary arteries anatomy and more recently, due to the introduction of stress-CCT and noninvasive fractional flow reserve (FFR-CT, functional relevance of CAD in a single shot scan. The current review evaluates the technical aspects and clinical experience of stress-CMR and CCT in the evaluation of functional relevance of CAD discussing the strength and weakness of each approach.

  12. When did cardiac surgery begin?

    Shumacker, H B

    1989-01-01

    Heart surgery is generally regarded as having begun on September 10, 1896 when Ludwig Rehn sutured a myocardial laceration successfully. There are valid reasons, however, to believe that cardiac surgery had its origin nearly a century earlier with the operative drainage of the pericardium by the little known Spanish surgeon, Francisco Romero, and highly regarded Baron Dominique Jean Larrey. This procedure entailed making a thoracic incision and opening and draining the pericardium. It must necessarily be considered a cardiac operation. The pericardium is part of the heart; its epicardium continues as the serosal layer of the fibrous pericardium; the pericardium is fused to the heart's base and great vessels; all books on heart surgery include pericardial operations. When Romero first operated is unknown, but it antedated 1814 when his work was presented in Paris; Larrey's operation was performed in 1810. These contributions are presented, and their priority with regard to the later initial efforts to suture myocardial laceration is reviewed briefly. PMID:2651455

  13. Accurate finite difference methods for time-harmonic wave propagation

    Harari, Isaac; Turkel, Eli

    1994-01-01

    Finite difference methods for solving problems of time-harmonic acoustics are developed and analyzed. Multidimensional inhomogeneous problems with variable, possibly discontinuous, coefficients are considered, accounting for the effects of employing nonuniform grids. A weighted-average representation is less sensitive to transition in wave resolution (due to variable wave numbers or nonuniform grids) than the standard pointwise representation. Further enhancement in method performance is obtained by basing the stencils on generalizations of Pade approximation, or generalized definitions of the derivative, reducing spurious dispersion, anisotropy and reflection, and by improving the representation of source terms. The resulting schemes have fourth-order accurate local truncation error on uniform grids and third order in the nonuniform case. Guidelines for discretization pertaining to grid orientation and resolution are presented.

  14. Historical perspectives of cardiac electrophysiology.

    Lüderitz, Berndt

    2009-01-01

    The diagnosis and treatment of clinical electrophysiology has a long and fascinating history. From earliest times, no clinical symptom impressed the patient (and the physician) more than an irregular heart beat. Although ancient Chinese pulse theory laid the foundation for the study of arrhythmias and clinical electrophysiology in the 5th century BC, the most significant breakthrough in the identification and treatment of cardiac arrhythmias first occurred in this century. In the last decades, our knowledge of electrophysiology and pharmacology has increased exponentially. The enormous clinical significance of cardiac rhythm disturbances has favored these advances. On the one hand, patients live longer and thus are more likely to experience arrhythmias. On the other hand, circulatory problems of the cardiac vessels have increased enormously, and this has been identified as the primary cause of cardiac rhythm disorders. Coronary heart disease has become not just the most significant disease of all, based on the statistics for cause of death. Arrhythmias are the main complication of ischemic heart disease, and they have been directly linked to the frequently arrhythmogenic sudden death syndrome, which is now presumed to be an avoidable "electrical accident" of the heart. A retrospective look--often charming in its own right--may not only make it easier to sort through the copious details of this field and so become oriented in this universe of important and less important facts: it may also provide the observer with a chronological vantage point from which to view the subject. The study of clinical electrophysiology is no dry compendium of facts and figures, but rather a dynamic field of study evolving out of the competition between various ideas, intentions and theories. PMID:19196616

  15. Cardiac rehabilitation: a comprehensive review

    Lear Scott A; Ignaszewski Andrew

    2001-01-01

    Abstract Cardiac rehabilitation (CR) is a commonly used treatment for men and women with cardiovascular disease. To date, no single study has conclusively demonstrated a comprehensive benefit of CR. Numerous individual studies, however, have demonstrated beneficial effects such as improved risk-factor profile, slower disease progression, decreased morbidity, and decreased mortality. This paper will review the evidence for the use of CR and discuss the implications and limitations of these stu...

  16. Cardiac Biomarkers in Hyperthyroid Cats

    Sangster, J.K.; Panciera, D L; Abbott, J.A.; Zimmerman, K.C.; Lantis, A.C.

    2013-01-01

    Background Hyperthyroidism has substantial effects on the circulatory system. The cardiac biomarkers NT‐proBNP and troponin I (cTNI) have proven useful in identifying cats with myocardial disease but have not been extensively investigated in hyperthyroidism. Hypothesis Plasma NT‐proBNP and cTNI concentrations are higher in cats with primary myocardial disease than in cats with hyperthyroidism and higher in cats with hyperthyroidism than in healthy control cats. Animals Twenty‐three hyperthyro...

  17. Functiogenesis of cardiac pacemaker activity.

    Sakai, Tetsuro; Kamino, Kohtaro

    2016-07-01

    Throughout our investigations on the ontogenesis of the electrophysiological events in early embryonic chick hearts, using optical techniques to record membrane potential probed with voltage-sensitive dyes, we have introduced a novel concept of "functiogenesis" corresponding to "morphogenesis". This article gives an account of the framework of "functiogenesis", focusing on the cardiac pacemaker function and the functional organization of the pacemaking area. PMID:26719289

  18. Comparative Aspects of Cardiac Adaptation

    Ošťádal, Bohuslav

    New York : Springer, 2013 - (Ošťádal, B.; Dhalla, N.), s. 3-18 ISBN 978-1-4614-5202-7. - (Advances in Biochemistry in Health and Disease) R&D Projects: GA ČR(CZ) GAP302/11/1308 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : cardiac adaptation * poikilotherms * homeotherms Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery

  19. Cardiac Biomarkers and Cycling Race

    Caroline Le Goff, Jean-François Kaux, Sébastien Goffaux, Etienne Cavalier

    2015-01-01

    In cycling as in other types of strenuous exercise, there exists a risk of sudden death. It is important both to understand its causes and to see if the behavior of certain biomarkers might highlight athletes at risk. Many reports describe changes in biomarkers after strenuous exercise (Nie et al., 2011), but interpreting these changes, and notably distinguishing normal physiological responses from pathological changes, is not easy. Here we have focused on the kinetics of different cardiac bi...

  20. Cardiac involvement in tuberous sclerosis.

    Mühler, E G; Turniski-Harder, V; Engelhardt, W.; von Bernuth, G

    1994-01-01

    OBJECTIVE--To assess the incidence, importance, and history of cardiac involvement in infants and children with tuberous sclerosis. DESIGN--Prospective study; clinical examination, sector and Doppler echocardiography, standard and ambulatory electrocardiography. SETTING--A tertiary referral centre. PATIENTS--21 patients with tuberous sclerosis aged 1 day to 16 years (mean 6.3 years); follow up investigations were available in 14 cases (10 retrospective, 4 prospective; mean follow up 4.3 years...

  1. Dissenting in Reflective Conversations

    Bjørn, Pernille; Boulus, Nina

    2011-01-01

    Reflective monitoring of research practices is essential. However, we often lack formal training in the practices of doing action research, and descriptions of actual inquiry practice are seldom included in publications. Our aim is to provide a glimpse of self-reflective practices based on our...

  2. Reflecting Magnon Bound States

    Ahn, C; Rey, S J

    2008-01-01

    In N=4 super Yang-Mills spin chain, we compute reflection amplitudes of magnon bound-state off giant graviton. We first compute the reflection amplitude off Y=0 brane boundary and compare it with the scattering amplitude between two magnon bound-states in the bulk. We find that analytic structure of the two amplitudes are intimately related each other: the boundary reflection amplitude is a square-root of the bulk scattering amplitude. Using such relation as a guide and taking known results at weak and strong coupling limits as inputs, we find the reflection amplitude of an elementary magnon off Z=0 giant graviton boundary. The reflection phase factor is shown to solve crossing and unitarity relations. We then compute the reflection amplitude of magnon bound-state off the Z=0 brane boundary and observe that its analytic structures are again intimately related to the bulk scattering and the Y=0 boundary reflection amplitudes. We also take dyonic giant magnon limit of these reflection amplitudes and confirm tha...

  3. Earth's Reflection: Albedo

    Gillette, Brandon; Hamilton, Cheri

    2011-01-01

    When viewing objects of different colors, you might notice that some appear brighter than others. This is because light is reflected differently from various surfaces, depending on their physical properties. The word "albedo" is used to describe how reflective a surface is. The Earth-atmosphere has a combined albedo of about 30%, a number that is…

  4. Cardiac MRI in restrictive cardiomyopathy

    Restrictive cardiomyopathy (RCM) is a specific group of heart muscle disorders characterized by inadequate ventricular relaxation during diastole. This leads to diastolic dysfunction with relative preservation of systolic function. Although short axis systolic function is usually preserved in RCM, the long axis systolic function may be severely impaired. Confirmation of diagnosis and information regarding aetiology, extent of myocardial damage, and response to treatment requires imaging. Importantly, differentiation from constrictive pericarditis (CCP) is needed, as only the latter is managed surgically. Echocardiography is the initial cardiac imaging technique but cannot reliably suggest a tissue diagnosis; although recent advances, especially tissue Doppler imaging and spectral tracking, have improved its ability to differentiate RCM from CCP. Cardiac catheterization is the reference standard, but is invasive, two-dimensional, and does not aid myocardial characterization. Cardiac magnetic resonance (CMR) is a versatile technique providing anatomical, morphological and functional information. In recent years, it has been shown to provide important information regarding disease mechanisms, and also been found useful to guide treatment, assess its outcome and predict patient prognosis. This review describes the CMR features of RCM, appearances in various diseases, its overall role in patient management, and how it compares with other imaging techniques.

  5. Cardiac MRI in restrictive cardiomyopathy

    Gupta, A. [Department of Cardiovascular Radiology, All India Institute of Medical Sciences, Ansari Nagar, Delhi (India); Singh Gulati, G., E-mail: gulatigurpreet@rediffmail.com [Department of Cardiovascular Radiology, All India Institute of Medical Sciences, Ansari Nagar, Delhi (India); Seth, S. [Department of Cardiology, All India Institute of Medical Sciences, Ansari Nagar, Delhi (India); Sharma, S. [Department of Cardiovascular Radiology, All India Institute of Medical Sciences, Ansari Nagar, Delhi (India)

    2012-02-15

    Restrictive cardiomyopathy (RCM) is a specific group of heart muscle disorders characterized by inadequate ventricular relaxation during diastole. This leads to diastolic dysfunction with relative preservation of systolic function. Although short axis systolic function is usually preserved in RCM, the long axis systolic function may be severely impaired. Confirmation of diagnosis and information regarding aetiology, extent of myocardial damage, and response to treatment requires imaging. Importantly, differentiation from constrictive pericarditis (CCP) is needed, as only the latter is managed surgically. Echocardiography is the initial cardiac imaging technique but cannot reliably suggest a tissue diagnosis; although recent advances, especially tissue Doppler imaging and spectral tracking, have improved its ability to differentiate RCM from CCP. Cardiac catheterization is the reference standard, but is invasive, two-dimensional, and does not aid myocardial characterization. Cardiac magnetic resonance (CMR) is a versatile technique providing anatomical, morphological and functional information. In recent years, it has been shown to provide important information regarding disease mechanisms, and also been found useful to guide treatment, assess its outcome and predict patient prognosis. This review describes the CMR features of RCM, appearances in various diseases, its overall role in patient management, and how it compares with other imaging techniques.

  6. Review Article of Cardiac Amyloidosis

    Jittiporn PURATTANAMAL

    2010-06-01

    Full Text Available Cardiac amyloidosis is a term that means the deposit of abnormal proteins in the myocardium leading to global thickening of the heart walls. The clinical character is that of infiltrative cardiomyopathy. AL amyloidosis is the most common type that involves cardiac failure. Cardiac amyloid precedes clinical congestive heart failure, especially right-sided heart failure. Laboratory investigations have identified the amyloid fibril proteins deposited in the organ tissues. Immunofixation tests are the most sensitive that recognize the paraprotein mean light chain protein or immunoglobulin subtype deposit. Prognosis is poor if AL amyloidosis is untreated. Treatment of systemic involvement in AL amyloidosis is via chemotherapy such as melphalan and prednisolone. UK experts have reported the results of treatment in AL amyloidosis. Regardless of the use of adjunctive chemotherapy, the five-year survival after heart transplantation was generally poorer for AL (20 % at five years, but similar for non-AL amyloidosis (64 % at five years, than heart transplants in other cases. Progression of the systemic disease contributed to increased mortality. A specific treatment that increases the chances of survival is unknown.

  7. Gastrointestinal complications and cardiac surgery.

    Allen, Sara J

    2014-06-01

    Gastrointestinal (GI) complications are an uncommon but potentially devastating complication of cardiac surgery. The reported incidence varies between .3% and 5.5% with an associated mortality of .3-87%. A wide range of GI complications are reported with bleeding, mesenteric ischemia, pancreatitis, cholecystitis, and ileus the most common. Ischemia is thought to be the main cause of GI complications with hypoperfusion during cardiac surgery as well as systemic inflammation, hypothermia, drug therapy, and mechanical factors contributing. Several nonischemic mechanisms may contribute to GI complications, including bacterial translocation, adverse drug reactions, and iatrogenic organ injury. Risk factors for GI complications are advanced age (>70 years), reoperation or emergency surgery, comorbidities (renal disease, respiratory disease, peripheral vascular disease, diabetes mellitus, cardiac failure), perioperative use of an intra-aortic balloon pump or inotrope therapy, prolonged surgery or cardiopulmonary bypass, and postoperative complications. Multiple strategies to reduce the incidence of GI complications exist, including risk stratification scores, targeted inotrope and fluid therapy, drug therapies, and modification of cardiopulmonary bypass. Currently, no single therapy has consistently proven efficacy in reducing GI complications. Timely diagnosis and treatment, while tailored to the specific complication and patient, is essential for optimal management and outcomes in this challenging patient population. PMID:25208431

  8. Sewage Reflects the Microbiomes of Human Populations

    Ryan J Newton; McLellan, Sandra L.; Dila, Deborah K.; Vineis, Joseph H; Morrison, Hilary G; Eren, A. Murat; Sogin, Mitchell L.

    2015-01-01

    ABSTRACT Molecular characterizations of the gut microbiome from individual human stool samples have identified community patterns that correlate with age, disease, diet, and other human characteristics, but resources for marker gene studies that consider microbiome trends among human populations scale with the number of individuals sampled from each population. As an alternative strategy for sampling populations, we examined whether sewage accurately reflects the microbial community of a mixt...

  9. Reflecting on Čerenkov reflections

    Fargion, D.; Gaug, M.; Oliva, P.

    2008-05-01

    MAGIC, as well as HESS and VERITAS, is a Čerenkov Telescope unveiling γ-ray sources above 60 GeV at vertical within noisy (hadronic) airshowering sky. These telescopes while facing the horizons may reveal rarest blazing UHECR as well as far fluorescence tails of downward PeV-EeV hadronic airshowers. Few of these inclined airshowers blazing on axis are spread by the geomagnetic field into twin spots. These twin flashes and their morphology may tag the UHECR origination site. There is a rich window of such reflecting Čerenkov lights visible by Telescopes on top of Mountains as MAGIC (and partially VERITAS): the reflections from the nearby ground (possibly enhanced by rain or snow, ice white cover), from the Sea and from the cloudy sky; in particular, these cloudy sheets may lay above or below the observer. MAGIC looking downward to the clouds or the snow, may well reveal blazing Moliere disks diffusing Čerenkov spots (few events per night). Because of geomagnetic forces and splitting of the inclined air-shower, one should reveal for the first time (at tens PeV or above) Čerenkov airshowers whose flashes are skimming the MAGIC nearby Sea and opened into twin spots. Their morphology may tag the UHECR origination, its consequent cross-section and composition. Magic telescopes looking upward into cloudy sky may observe very rare up-going UHE Tau, originated by UHE PeVs neutrinos skimming earth, air-showering into sky, reflecting into clouds. In particular Glashow resonant antineutrinos electron hitting into Earth electrons may lead to gauged boson W-, whose decay (inside the Earth) may produce a τ + bar nuτ [3], which later escape and decay in air is producing Čerenkov lights; these flashes may blaze into the clouds above MAGIC as upward dot spots. The Magic energy threshold for such UHE Neutrinos showers rises to PeV values. EeV UHE tau neutrinos by guaranteed GZK UHECR secondaries [6, 16], via the muon-tau flavor mixing, may skim the Earth, produce UHE tau

  10. Inhaled nitric oxide in cardiac surgery: Evidence or tradition?

    Benedetto, Maria; Romano, Rosalba; Baca, Georgiana; Sarridou, Despoina; Fischer, Andreas; Simon, Andre; Marczin, Nandor

    2015-09-15

    Inhaled nitric oxide (iNO) therapy as a selective pulmonary vasodilator in cardiac surgery has been one of the most significant pharmacological advances in managing pulmonary hemodynamics and life threatening right ventricular dysfunction and failure. However, this remarkable story has experienced a roller-coaster ride with high hopes and nearly universal demonstration of physiological benefits but disappointing translation of these benefits to harder clinical outcomes. Most of our understanding on the iNO field in cardiac surgery stems from small observational or single centre randomised trials and even the very few multicentre trials fail to ascertain strong evidence base. As a consequence, there are only weak clinical practice guidelines on the field and only European expert opinion for the use of iNO in routine and more specialised cardiac surgery such as heart and lung transplantation and left ventricular assist device (LVAD) insertion. In this review the authors from a specialised cardiac centre in the UK with a very high volume of iNO usage provide detailed information on the early observations leading to the European expert recommendations and reflect on the nature and background of these recommendations. We also provide a summary of the progress in each of the cardiac subspecialties for the last decade and initial survey data on the views of senior anaesthetic and intensive care colleagues on these recommendations. We conclude that the combination of high price tag associated with iNO therapy and lack of substantial clinical evidence is not sustainable on the current field and we are risking loosing this promising therapy from our daily practice. Overcoming the status quo will not be easy as there is not much room for controlled trials in heart transplantation or in the current atmosphere of LVAD implantation. However, we call for international cooperation to conduct definite studies to determine the place of iNO therapy in lung transplantation and high

  11. Early cardiac changes related to radiation therapy

    To investigate the incidence and severity of possible radiation-induced cardiac changes, 21 women without heart disease were investigated serially by echocardiography and by measuring systolic time intervals before and up to 6 months after postoperative radiation therapy because of breast cancer. Radiation was associated with a decrease in fractional systolic shortening of the left ventricular (LV) minor-axis diameter, from 0.35 +/- 0.05 to 0.32 +/- 0.06 (p less than 0.005), and in the systolic blood pressure/end-systolic diameter ratio, from 4.4 +/- 1.2 to 3.9 +/- 0.9 mm Hg/mm (p less than 0.005). The mitral E point-septal separation increased, from 2.8 +/- 1.5 to 4.2 +/- 2.5 mm (p less than 0.005). The preejection period/LV ejection time ratio of systolic time intervals increased, but only the decrease within 6 months after therapy was significant (p less than 0.005). All these changes reflect slight transient depression of LV function, which became normalized within 6 months after therapy. Up to 6 months after therapy, a slight pericardial effusion was found in 33% of the patients. Hence, conventional radiation therapy appeared to cause an acute transient and usually symptomless decrease in LV function, and later, slight pericardial effusion in one-third of the patients

  12. Pharmacological treatment of cardiac glycoside poisoning.

    Roberts, Darren M; Gallapatthy, Gamini; Dunuwille, Asunga; Chan, Betty S

    2016-03-01

    Cardiac glycosides are an important cause of poisoning, reflecting their widespread clinical usage and presence in natural sources. Poisoning can manifest as varying degrees of toxicity. Predominant clinical features include gastrointestinal signs, bradycardia and heart block. Death occurs from ventricular fibrillation or tachycardia. A wide range of treatments have been used, the more common including activated charcoal, atropine, β-adrenoceptor agonists, temporary pacing, anti-digoxin Fab and magnesium, and more novel agents include fructose-1,6-diphosphate (clinical trial in progress) and anticalin. However, even in the case of those treatments that have been in use for decades, there is debate regarding their efficacy, the indications and dosage that optimizes outcomes. This contributes to variability in use across the world. Another factor influencing usage is access. Barriers to access include the requirement for transfer to a specialized centre (for example, to receive temporary pacing) or financial resources (for example, anti-digoxin Fab in resource poor countries). Recent data suggest that existing methods for calculating the dose of anti-digoxin Fab in digoxin poisoning overstate the dose required, and that its efficacy may be minimal in patients with chronic digoxin poisoning. Cheaper and effective medicines are required, in particular for the treatment of yellow oleander poisoning which is problematic in resource poor countries. PMID:26505271

  13. Feedback about more accurate versus less accurate trials: differential effects on self-confidence and activation.

    Badami, Rokhsareh; VaezMousavi, Mohammad; Wulf, Gabriele; Namazizadeh, Mahdi

    2012-06-01

    One purpose of the present study was to examine whether self-confidence or anxiety would be differentially affected byfeedback from more accurate rather than less accurate trials. The second purpose was to determine whether arousal variations (activation) would predict performance. On day 1, participants performed a golf putting task under one of two conditions: one group received feedback on the most accurate trials, whereas another group received feedback on the least accurate trials. On day 2, participants completed an anxiety questionnaire and performed a retention test. Shin conductance level, as a measure of arousal, was determined. The results indicated that feedback about more accurate trials resulted in more effective learning as well as increased self-confidence. Also, activation was a predictor of performance. PMID:22808705

  14. The seismic reflection inverse problem

    The seismic reflection method seeks to extract maps of the Earth's sedimentary crust from transient near-surface recording of echoes, stimulated by explosions or other controlled sound sources positioned near the surface. Reasonably accurate models of seismic energy propagation take the form of hyperbolic systems of partial differential equations, in which the coefficients represent the spatial distribution of various mechanical characteristics of rock (density, stiffness, etc). Thus the fundamental problem of reflection seismology is an inverse problem in partial differential equations: to find the coefficients (or at least some of their properties) of a linear hyperbolic system, given the values of a family of solutions in some part of their domains. The exploration geophysics community has developed various methods for estimating the Earth's structure from seismic data and is also well aware of the inverse point of view. This article reviews mathematical developments in this subject over the last 25 years, to show how the mathematics has both illuminated innovations of practitioners and led to new directions in practice. Two themes naturally emerge: the importance of single scattering dominance and compensation for spectral incompleteness by spatial redundancy. (topical review)

  15. Machine learning of parameters for accurate semiempirical quantum chemical calculations

    We investigate possible improvements in the accuracy of semiempirical quantum chemistry (SQC) methods through the use of machine learning (ML) models for the parameters. For a given class of compounds, ML techniques require sufficiently large training sets to develop ML models that can be used for adapting SQC parameters to reflect changes in molecular composition and geometry. The ML-SQC approach allows the automatic tuning of SQC parameters for individual molecules, thereby improving the accuracy without deteriorating transferability to molecules with molecular descriptors very different from those in the training set. The performance of this approach is demonstrated for the semiempirical OM2 method using a set of 6095 constitutional isomers C7H10O2, for which accurate ab initio atomization enthalpies are available. The ML-OM2 results show improved average accuracy and a much reduced error range compared with those of standard OM2 results, with mean absolute errors in atomization enthalpies dropping from 6.3 to 1.7 kcal/mol. They are also found to be superior to the results from specific OM2 reparameterizations (rOM2) for the same set of isomers. The ML-SQC approach thus holds promise for fast and reasonably accurate high-throughput screening of materials and molecules

  16. How Accurate is inv(A)*b?

    Druinsky, Alex

    2012-01-01

    Several widely-used textbooks lead the reader to believe that solving a linear system of equations Ax = b by multiplying the vector b by a computed inverse inv(A) is inaccurate. Virtually all other textbooks on numerical analysis and numerical linear algebra advise against using computed inverses without stating whether this is accurate or not. In fact, under reasonable assumptions on how the inverse is computed, x = inv(A)*b is as accurate as the solution computed by the best backward-stable solvers. This fact is not new, but obviously obscure. We review the literature on the accuracy of this computation and present a self-contained numerical analysis of it.

  17. Accurate guitar tuning by cochlear implant musicians.

    Thomas Lu

    Full Text Available Modern cochlear implant (CI users understand speech but find difficulty in music appreciation due to poor pitch perception. Still, some deaf musicians continue to perform with their CI. Here we show unexpected results that CI musicians can reliably tune a guitar by CI alone and, under controlled conditions, match simultaneously presented tones to <0.5 Hz. One subject had normal contralateral hearing and produced more accurate tuning with CI than his normal ear. To understand these counterintuitive findings, we presented tones sequentially and found that tuning error was larger at ∼ 30 Hz for both subjects. A third subject, a non-musician CI user with normal contralateral hearing, showed similar trends in performance between CI and normal hearing ears but with less precision. This difference, along with electric analysis, showed that accurate tuning was achieved by listening to beats rather than discriminating pitch, effectively turning a spectral task into a temporal discrimination task.

  18. Accurate guitar tuning by cochlear implant musicians.

    Lu, Thomas; Huang, Juan; Zeng, Fan-Gang

    2014-01-01

    Modern cochlear implant (CI) users understand speech but find difficulty in music appreciation due to poor pitch perception. Still, some deaf musicians continue to perform with their CI. Here we show unexpected results that CI musicians can reliably tune a guitar by CI alone and, under controlled conditions, match simultaneously presented tones to <0.5 Hz. One subject had normal contralateral hearing and produced more accurate tuning with CI than his normal ear. To understand these counterintuitive findings, we presented tones sequentially and found that tuning error was larger at ∼ 30 Hz for both subjects. A third subject, a non-musician CI user with normal contralateral hearing, showed similar trends in performance between CI and normal hearing ears but with less precision. This difference, along with electric analysis, showed that accurate tuning was achieved by listening to beats rather than discriminating pitch, effectively turning a spectral task into a temporal discrimination task. PMID:24651081

  19. Accurate Finite Difference Methods for Option Pricing

    Persson, Jonas

    2006-01-01

    Stock options are priced numerically using space- and time-adaptive finite difference methods. European options on one and several underlying assets are considered. These are priced with adaptive numerical algorithms including a second order method and a more accurate method. For American options we use the adaptive technique to price options on one stock with and without stochastic volatility. In all these methods emphasis is put on the control of errors to fulfill predefined tolerance level...

  20. Accurate, reproducible measurement of blood pressure.

    Campbell, N. R.; Chockalingam, A; Fodor, J. G.; McKay, D. W.

    1990-01-01

    The diagnosis of mild hypertension and the treatment of hypertension require accurate measurement of blood pressure. Blood pressure readings are altered by various factors that influence the patient, the techniques used and the accuracy of the sphygmomanometer. The variability of readings can be reduced if informed patients prepare in advance by emptying their bladder and bowel, by avoiding over-the-counter vasoactive drugs the day of measurement and by avoiding exposure to cold, caffeine con...

  1. Accurate variational forms for multiskyrmion configurations

    Jackson, A.D.; Weiss, C.; Wirzba, A.; Lande, A.

    1989-04-17

    Simple variational forms are suggested for the fields of a single skyrmion on a hypersphere, S/sub 3/(L), and of a face-centered cubic array of skyrmions in flat space, R/sub 3/. The resulting energies are accurate at the level of 0.2%. These approximate field configurations provide a useful alternative to brute-force solutions of the corresponding Euler equations.

  2. Efficient Accurate Context-Sensitive Anomaly Detection

    2007-01-01

    For program behavior-based anomaly detection, the only way to ensure accurate monitoring is to construct an efficient and precise program behavior model. A new program behavior-based anomaly detection model,called combined pushdown automaton (CPDA) model was proposed, which is based on static binary executable analysis. The CPDA model incorporates the optimized call stack walk and code instrumentation technique to gain complete context information. Thereby the proposed method can detect more attacks, while retaining good performance.

  3. Towards accurate modeling of moving contact lines

    Holmgren, Hanna

    2015-01-01

    The present thesis treats the numerical simulation of immiscible incompressible two-phase flows with moving contact lines. The conventional Navier–Stokes equations combined with a no-slip boundary condition leads to a non-integrable stress singularity at the contact line. The singularity in the model can be avoided by allowing the contact line to slip. Implementing slip conditions in an accurate way is not straight-forward and different regularization techniques exist where ad-hoc procedures ...

  4. Reflection and teaching: a taxonomy

    Vos, Henk; Cowan, John

    2009-01-01

    A major problem in teaching reflection is that educational objectives for reflection in terms of student behaviour are lacking. Therefore a taxonomy of reflection has been developed based on Bloom’s taxonomy. Reflective assignments can then be better focused on any chosen educational objectives. The act of reflection has been analysed and abstracted from goal, content, context, means, and moment of reflecting. Reflection was operationalised as answering reflective questions. Bloom’s taxonomy ...

  5. Accurate phase-shift velocimetry in rock

    Shukla, Matsyendra Nath; Vallatos, Antoine; Phoenix, Vernon R.; Holmes, William M.

    2016-06-01

    Spatially resolved Pulsed Field Gradient (PFG) velocimetry techniques can provide precious information concerning flow through opaque systems, including rocks. This velocimetry data is used to enhance flow models in a wide range of systems, from oil behaviour in reservoir rocks to contaminant transport in aquifers. Phase-shift velocimetry is the fastest way to produce velocity maps but critical issues have been reported when studying flow through rocks and porous media, leading to inaccurate results. Combining PFG measurements for flow through Bentheimer sandstone with simulations, we demonstrate that asymmetries in the molecular displacement distributions within each voxel are the main source of phase-shift velocimetry errors. We show that when flow-related average molecular displacements are negligible compared to self-diffusion ones, symmetric displacement distributions can be obtained while phase measurement noise is minimised. We elaborate a complete method for the production of accurate phase-shift velocimetry maps in rocks and low porosity media and demonstrate its validity for a range of flow rates. This development of accurate phase-shift velocimetry now enables more rapid and accurate velocity analysis, potentially helping to inform both industrial applications and theoretical models.

  6. Cardiac tamponade: contrast reflux as an indicator of cardiac chamber equalization

    Nauta Foeke Jacob

    2012-05-01

    Full Text Available Abstract Background Traumatic hemopericardium remains a rare entity; it does however commonly cause cardiac tamponade which remains a major cause of death in traumatic blunt cardiac injury. Objectives We present a case of blunt chest trauma complicated by cardiac tamponade causing cardiac chamber equalization revealed by reflux of contrast. Case report A 29-year-old unidentified male suffered blunt chest trauma in a motor vehicle collision. Computed tomography (CT demonstrated a periaortic hematoma and hemopericardium. Significant contrast reflux was seen in the inferior vena cava and hepatic veins suggesting a change in cardiac chamber pressures. After intensive treatment including cardiac massage this patient expired of cardiac arrest. Conclusion Reflux of contrast on CT imaging can be an indicator of traumatic cardiac tamponade.

  7. Review of Teacher's Teaching Reflection

    王爽爽

    2015-01-01

    Teacher's teaching reflection has become the core focus in school.However,there are different understandings of the concept of teacher's teaching reflection.The paper introduces and compares different understandings of the concept of teachers' teaching reflection.Based on the summarizing of the concept on reflection and teaching reflection,this paper tries to provide reference for the teacher's teaching reflection.

  8. Cardiac Stem Cells: Biology and Clinical Applications

    Goichberg, Polina; Chang, Jerway; Liao, Ronglih; Leri, Annarosa

    2014-01-01

    Significance: Heart disease is the primary cause of death in the industrialized world. Cardiac failure is dictated by an uncompensated reduction in the number of viable and fully functional cardiomyocytes. While current pharmacological therapies alleviate the symptoms associated with cardiac deterioration, heart transplantation remains the only therapy for advanced heart failure. Therefore, there is a pressing need for novel therapeutic modalities. Cell-based therapies involving cardiac stem ...

  9. Cardiac imaging: Current and emerging applications

    Jankharia B; Raut A

    2010-01-01

    Cardiac magnetic resonance imaging (MRI) and computed tomography (CT) scan have made big inroads as modalities used for evaluation of various pathologies of the heart. Cardiac MRI is typically used for perfusion and viability studies as well as to study various cardiomyopathies, valvular diseases and the pericardium. It has been used in the evaluation of congenital heart diseases over the last two decades. Cardiac CT is used mainly for the evaluation of the coronary arteries, typically in the...

  10. Disseminated cysticercosis with pulmonary and cardiac involvement

    Jain Bharat; Sankhe Shilpa; Agrawal Mukta; Naphade Prashant

    2010-01-01

    Pulmonary and cardiac involvement by cysticercosis is extremely rare, and is usually asymptomatic. We report the case of a 19-year-old boy who presented with a history of headache and vomiting and was found to have disseminated cysticercosis with pulmonary and cardiac involvement; the emphasis is on the rare occurrence of pulmonary, cardiac, pancreatic, intraocular, and extradural spinal canal involvement in the same patient. This case demonstrates the extent to which cysticercosis can be dis...

  11. Motivational factors of adherence to cardiac rehabilitation

    Shahsavari, Hooman; Shahriari, Mohsen; Alimohammadi, Nasrollah

    2012-01-01

    Background: Main suggested theories about patients’ adherence to treatment regimens recognize the importance of motivation in positive changes in behaviors. Since cardiac diseases are chronic and common, cardiac rehabilitation as an effective prevention program is crucial in management of these diseases. There is always concern about the patients’ adherence to cardiac rehabilitation. The aim of this study was to describe the motivational factors affecting the patients’ participation and compl...

  12. Cardiac tumours simulating collagen vascular disease.

    Fitzpatrick, A. P.; Lanham, J. G.; Doyle, D V

    1986-01-01

    Cardiac tumours can mimic collagen vascular disease and they are often accompanied by profound systemic upset. Both benign and malignant tumours may present in this way. Three cases of cardiac tumour, two malignant and one benign, are reported with just such a presentation. A review of fifteen similar case reports showed that a spectrum of different collagen vascular diseases was diagnosed and treated before the true diagnosis emerged. In half of these cases the cardiac tumour was only diagno...

  13. Electrocardiographically Determination of Cardiac Enlargements in Dogs

    Gönül, Remzi; OR, Mehmet Erman; DODURKA, Tamer

    2002-01-01

    In this study, the electrocardiographic parameters necessary to determine cardiac enlargements and to establish and distinguish such complaints from each other in the early stage in dogs with circulatory problems were assessed. The material of the study consisted of 33 dogs 1.5-15 years of age with cardiac enlargements determined from 140 dogs suspected of having cardiac disease based on clinical, radiographic and electrocardiographic analyses. In these dogs, 12 cases of left atrial hypert...

  14. Interdisciplinary preoperative patient education in cardiac surgery.

    De Weert, J.; van Dulmen, S.; Bar, P.; Venus, E.

    2003-01-01

    Patient education in cardiac surgery is complicated by the fact that cardiac surgery patients meet a lot of different health care providers. Little is known about education processes in terms of interdisciplinary tuning. In this study, complete series of consecutive preoperative consultations of 51 cardiac surgery patients with different health care providers (physicians, nurses and health educators) were videotaped. The information exchange between patients and providers was analyzed directl...

  15. Virtual and augmented medical imaging environments: enabling technology for minimally invasive cardiac interventional guidance.

    Linte, Cristian A; White, James; Eagleson, Roy; Guiraudon, Gérard M; Peters, Terry M

    2010-01-01

    Virtual and augmented reality environments have been adopted in medicine as a means to enhance the clinician's view of the anatomy and facilitate the performance of minimally invasive procedures. Their value is truly appreciated during interventions where the surgeon cannot directly visualize the targets to be treated, such as during cardiac procedures performed on the beating heart. These environments must accurately represent the real surgical field and require seamless integration of pre- and intra-operative imaging, surgical tracking, and visualization technology in a common framework centered around the patient. This review begins with an overview of minimally invasive cardiac interventions, describes the architecture of a typical surgical guidance platform including imaging, tracking, registration and visualization, highlights both clinical and engineering accuracy limitations in cardiac image guidance, and discusses the translation of the work from the laboratory into the operating room together with typically encountered challenges. PMID:22275200

  16. Constant infusion transpulmonary thermodilution for the assessment of cardiac output in exercising humans

    Calbet, J A L; Mortensen, Stefan; Munch, G D W;

    2016-01-01

    To determine the accuracy and precision of constant infusion transpulmonary thermodilution cardiac output (CITT-Q) assessment during exercise in humans, using indocyanine green (ICG) dilution and bolus transpulmonary thermodilution (BTD) as reference methods, cardiac output (Q) was determined at...... rest and during incremental one- and two-legged pedaling on a cycle ergometer, and combined arm cranking with leg pedaling to exhaustion in 15 healthy men. Continuous infusions of iced saline in the femoral vein (n = 41) or simultaneously in the femoral and axillary (n = 66) veins with determination of......: 6.1-11.1%). In conclusion, cardiac output can be precisely and accurately determined with constant infusion transpulmonary thermodilution in exercising humans....

  17. Cardiac output determined by echocardiography in patients with cirrhosis: comparison with the indicator dilution technique

    Andersen, Ulrik B; Møller, Søren; Bendtsen, Flemming; Henriksen, Jens H

    2003-01-01

    technique (CO(I)). METHODS: Twelve patients with cirrhosis were studied. CO(d) was measured as the spatial mean velocity of the left ventricular outflow tract, multiplied by the cross-sectional area and the heart rate. CO(I) was determined by the standard indicator dilution technique after injection of 125I......BACKGROUND/AIMS: Measurement of cardiac output in hyperkinetic patients with cirrhosis by Doppler echocardiography is increasingly reported, but has not been validated. We have compared simultaneous measurements of cardiac output by Doppler echocardiography (CO(d)) and by the indicator dilution...... with the Doppler technique. CONCLUSION: Doppler measurements of cardiac output in groups of patients with cirrhosis are accurate with respect to the group mean, but marked disagreements of over- and underestimation were seen in individual patients. The reproducibility of the Doppler technique is...

  18. Value reflected health education

    Wistoft, Karen; Nordentoft, Helle Merete

    2011-01-01

    This article examines the impact of a value-reflected approach in health education by demonstrating the nature of professional competence development connected to this approach. It is based on findings from two three-year health educational development projects carried out by school health nurses...... and researchers at primary schools in Denmark from 2004-2009. We argue for the importance of reflecting on values in school health nursing in order to navigate between human values and values deriving from medicine. Our studies demonstrate that value clarification, peer observation and reflective spaces at work...... develop pedagogical competences in health education improving school childrens’ health....

  19. Contemporary Breast Radiotherapy and Cardiac Toxicity.

    Yeboa, Debra Nana; Evans, Suzanne Buckley

    2016-01-01

    Long-term cardiac effects are an important component of survivorship after breast radiotherapy. The pathophysiology of cardiotoxicity, history of breast radiotherapy, current methods of cardiac avoidance, modern outcomes, context of historical outcomes, quantifying cardiac effects, and future directions are reviewed in this article. Radiation-induced oxidative stress induces proinflammatory cytokines and is a process that potentiates late effects of fibrosis and intimal proliferation in endothelial vasculature. Breast radiation therapy has changed substantially in recent decades. Several modern technologies exist to improve cardiac avoidance such as deep inspiration breath hold, gating, accelerated partial breast irradiation, and use of modern 3-dimensional planning. Modern outcomes may vary notably from historical long-term cardiac outcomes given the differences in cardiac dose with modern techniques. Methods of quantifying radiation-related cardiotoxicity that correlate with future cardiac risks are needed with current data exploring techniques such as measuring computed tomography coronary artery calcium score, single-photon emission computed tomography imaging, and biomarkers. Placing historical data, dosimetric correlations, and relative cardiac risk in context are key when weighing the benefits of radiotherapy in breast cancer control and survival. Estimating present day cardiac risk in the modern treatment era includes challenges in length of follow-up and the use of confounding cardiotoxic agents such as evolving systemic chemotherapy and targeted therapies. Future directions in both multidisciplinary management and advancing technology in radiation oncology may provide further improvements in patient risk reduction and breast cancer survivorship. PMID:26617212

  20. MRI in cardiac sarcoidosis and amyloidosis

    Sarcoidosis and amyloidosis are both multisystem disorders, which may involve the heart; however, isolated cardiac disease is rare. Diagnosis of cardiac sarcoidosis and amyloidosis is crucial because the patient prognosis is dependent on cardiac involvement and early treatment. Echocardiography is the first line imaging modality in the diagnostic work-up of both diseases, possibly giving hints towards the correct diagnosis. Besides myocardial biopsy and radionuclide studies cardiac magnetic resonance imaging (MRI) is routinely performed in patients suspect of having infiltrative cardiomyopathy. The T1 mapping procedure is currently being evaluated as a new technique for detection and quantification of global myocardial enhancement, as seen in cardiac amyloidosis. Sensitivities and specificities for detection of cardiac sarcoidosis and amyloidosis can be significantly improved by MRI, especially with late gadolinium enhancement (LGE) imaging. In cardiac sarcoidosis the use of LGE is outcome-related while in amyloidosis analysis of T1-mapping may be of prognostic value. If cardiac involvement in sarcoidosis or amyloidosis is suspected cardiac MRI including LGE should be performed for establishing the diagnosis. (orig.)

  1. [Out-of-hospital cardiac arrest].

    Virkkunen, Ilkka; Hoppu, Sanna; Kämäräinen, Antti

    2011-01-01

    Cardiac arrest as the first symptom of coronary artery disease is not uncommon. Some of previously healthy people with sudden cardiac arrest may be saved by effective resuscitation and post-resuscitative therapy. The majority of cardiac arrest patients experience the cardiac arrest outside of the hospital, in which case early recognition of lifelessness, commencement of basic life support and entry to professional care without delay are the prerequisites for recovery. After the heart has started beating again, the clinical picture of post-resuscitation syndrome must be recognized and appropriate treatment utilized. PMID:22204143

  2. Cardiac tissue engineering in magnetically actuated scaffolds

    Cardiac tissue engineering offers new possibilities for the functional and structural restoration of damaged or lost heart tissue by applying cardiac patches created in vitro. Engineering such functional cardiac patches is a complex mission, involving material design on the nano- and microscale as well as the application of biological cues and stimulation patterns to promote cell survival and organization into a functional cardiac tissue. Herein, we present a novel strategy for creating a functional cardiac patch by combining the use of a macroporous alginate scaffold impregnated with magnetically responsive nanoparticles (MNPs) and the application of external magnetic stimulation. Neonatal rat cardiac cells seeded within the magnetically responsive scaffolds and stimulated by an alternating magnetic field of 5 Hz developed into matured myocardial tissue characterized by anisotropically organized striated cardiac fibers, which preserved its features for longer times than non-stimulated constructs. A greater activation of AKT phosphorylation in cardiac cell constructs after applying a short-term (20 min) external magnetic field indicated the efficacy of magnetic stimulation to actuate at a distance and provided a possible mechanism for its action. Our results point to a synergistic effect of magnetic field stimulation together with nanoparticulate features of the scaffold surface as providing the regenerating environment for cardiac cells driving their organization into functionally mature tissue. (paper)

  3. A comparison of genetic findings in sudden cardiac death victims and cardiac patients

    Hertz, Christin L; Ferrero-Miliani, Laura; Frank-Hansen, Rune;

    2015-01-01

    Sudden cardiac death (SCD) is responsible for a large proportion of non-traumatic, sudden and unexpected deaths in young individuals. Sudden cardiac death is a known manifestation of several inherited cardiac diseases. In post-mortem examinations, about two-thirds of the SCD cases show structural...

  4. [Thoracic lavage and open cardiac massage as treatment of hypothermic cardiac arrest--case report].

    Koponen, Timo; Vänni, Ville; Kettunen, Minna; Reinikainen, Matti; Hakala, Tapio

    2016-01-01

    Cardiopulmonary bypass is the treatment of choice for a severely hypothermic patient with cardiac arrest. However, the treatment is not always available. We describe a successful three-and-a-half hour resuscitation of a hypothermic cardiac arrest patient with manual chest compressions followed by open cardiac massage and rewarming with thoracic lavage. PMID:27188092

  5. Ray-Based Reflectance Model for Diffraction

    Cuypers, Tom; Haber, Tom; Bekaert, Philippe; Raskar, Ramesh

    2011-01-01

    We present a novel method of simulating wave effects in graphics using ray--based renderers with a new function: the Wave BSDF (Bidirectional Scattering Distribution Function). Reflections from neighboring surface patches represented by local BSDFs are mutually independent. However, in many surfaces with wavelength-scale microstructures, interference and diffraction requires a joint analysis of reflected wavefronts from neighboring patches. We demonstrate a simple method to compute the BSDF for the entire microstructure, which can be used independently for each patch. This allows us to use traditional ray--based rendering pipelines to synthesize wave effects of light and sound. We exploit the Wigner Distribution Function (WDF) to create transmissive, reflective, and emissive BSDFs for various diffraction phenomena in a physically accurate way. In contrast to previous methods for computing interference, we circumvent the need to explicitly keep track of the phase of the wave by using BSDFs that include positiv...

  6. Dissenting in Reflective Conversations

    Bjørn, Pernille; Boulus-Rødje, Nina

    2011-01-01

    Reflective monitoring of research practices is essential. However, we often lack formal training in the practices of doing action research, and descriptions of actual inquiry practice are seldom included in publications. Our aim is to provide a glimpse of self-reflective practices based on our...... experience of enacting action research. Our engagement in a large action research project brought about many dilemmas and uncertainties related to our roles and interventions. We focus on these uncertainties as a way of opening the ?black box? of action research ?in the making?. We conceptualize a...... methodological reflective approach that provides space for taking seriously uncertainties experienced in the field as these can be a catalyst for learning and sharpening our theoretical and empirical skills as action researchers. Through first-person inquiry, we investigate how our reflective conversations...

  7. Andreev reflection in graphene

    Beenakker, Carlo

    2007-03-01

    Relativity and superconductivity have no common ground in ordinary matter, because the velocity of electrons is only a small fraction of the velocity of light. The unusual band structure of a single layer of carbon atoms (graphene) contains negatively and positively charged particles that move as relativistic electrons and positrons. The electron-like particles in the conduction band can be converted into positron-like particles in the valence band when they are reflected by a superconductor. (The missing charge of 2e enters the superconductor as a Cooper pair.) This interband reflection process can be distinguished from the usual intraband Andreev reflection, because the reflection angle has the opposite sign. A new phenomenology of graphene--superconductor junctions is predicted, including an anomalous scaling of the supercurrent with the length of the junction and the existence of charge-neutral modes propagating along the interface.

  8. Selectively reflective transparent sheets

    Waché, Rémi; Florescu, Marian; Sweeney, Stephen J.; Clowes, Steven K.

    2015-08-01

    We investigate the possibility to selectively reflect certain wavelengths while maintaining the optical properties on other spectral ranges. This is of particular interest for transparent materials, which for specific applications may require high reflectivity at pre-determined frequencies. Although there exist currently techniques such as coatings to produce selective reflection, this work focuses on new approaches for mass production of polyethylene sheets which incorporate either additives or surface patterning for selective reflection between 8 to 13 μ m. Typical additives used to produce a greenhouse effect in plastics include particles such as clays, silica or hydroxide materials. However, the absorption of thermal radiation is less efficient than the decrease of emissivity as it can be compared with the inclusion of Lambertian materials. Photonic band gap engineering by the periodic structuring of metamaterials is known in nature for producing the vivid bright colors in certain organisms via strong wavelength-selective reflection. Research to artificially engineer such structures has mainly focused on wavelengths in the visible and near infrared. However few studies to date have been carried out to investigate the properties of metastructures in the mid infrared range even though the patterning of microstructure is easier to achieve. We present preliminary results on the diffuse reflectivity using FDTD simulations and analyze the technical feasibility of these approaches.

  9. Thoughts on Reflection (Editorial

    Denise Koufogiannakis

    2010-06-01

    Full Text Available There has been some acknowledgement in the published literature that reflection is a crucial element of the evidence based library and information practice (EBLIP model we have adopted (Booth 2004, 2006; Grant 2007; Helliwell 2007. As we work through a problem and try to incorporate the best available evidence into our decision making, reflection is required at several stages, including the very identification of the problem through to our assessment of the process itself and what we have learned in order to inform future practice. However, reflection and reflective writing have not fully been integrated into the process we espouse, and very little has been done to look more closely at this element of the model and how it can be integrated into professional learning.In a recently published research article, Sen (2010 confirms the relationship between reflection and several aspects of professional practice. These include critical review and decision making, two aspects that are tied closely to the evidence based process. Sen notes: Students were more likely to show evidence of learning, self‐development, the ability to review issues crucially, awareness of their own mental functions, ability to make decision [sic] and being empowered when they had mastered the art of reflective practice and the more deeply analytical reflective writing. (p.84 EBLIP (the journal tries to incorporate elements of reflection within the articles we publish. While we clearly believe in the need for our profession to do quality research and publish that research so that it can be accessible to practitioners, we also know that research cannot be looked at in isolation. Our evidence summaries are one way of reflecting critically on previously published research, and in the same vein, our classics bring older research studies back to the foreground. This work needs to continue to be discussed and looked at for its impact on our profession.More directly, the Using

  10. Niche Genetic Algorithm with Accurate Optimization Performance

    LIU Jian-hua; YAN De-kun

    2005-01-01

    Based on crowding mechanism, a novel niche genetic algorithm was proposed which can record evolutionary direction dynamically during evolution. After evolution, the solutions's precision can be greatly improved by means of the local searching along the recorded direction. Simulation shows that this algorithm can not only keep population diversity but also find accurate solutions. Although using this method has to take more time compared with the standard GA, it is really worth applying to some cases that have to meet a demand for high solution precision.

  11. How accurately can we calculate thermal systems?

    The objective was to determine how accurately simple reactor lattice integral parameters can be determined, considering user input, differences in the methods, source data and the data processing procedures and assumptions. Three simple square lattice test cases with different fuel to moderator ratios were defined. The effect of the thermal scattering models were shown to be important and much bigger than the spread in the results. Nevertheless, differences of up to 0.4% in the K-eff calculated by continuous energy Monte Carlo codes were observed even when the same source data were used. (author)

  12. Accurate diagnosis is essential for amebiasis

    2004-01-01

    @@ Amebiasis is one of the three most common causes of death from parasitic disease, and Entamoeba histolytica is the most widely distributed parasites in the world. Particularly, Entamoeba histolytica infection in the developing countries is a significant health problem in amebiasis-endemic areas with a significant impact on infant mortality[1]. In recent years a world wide increase in the number of patients with amebiasis has refocused attention on this important infection. On the other hand, improving the quality of parasitological methods and widespread use of accurate tecniques have improved our knowledge about the disease.

  13. Investigations on Accurate Analysis of Microstrip Reflectarrays

    Zhou, Min; Sørensen, S. B.; Kim, Oleksiy S.;

    2011-01-01

    An investigation on accurate analysis of microstrip reflectarrays is presented. Sources of error in reflectarray analysis are examined and solutions to these issues are proposed. The focus is on two sources of error, namely the determination of the equivalent currents to calculate the radiation...... pattern, and the inaccurate mutual coupling between array elements due to the lack of periodicity. To serve as reference, two offset reflectarray antennas have been designed, manufactured and measured at the DTUESA Spherical Near-Field Antenna Test Facility. Comparisons of simulated and measured data are...

  14. Techniques of cardiac output measurement during liver transplantation: arterial pulse wave versus thermodilution

    Nissen, P.; Lieshout, J.J. van; Novovic, S.;

    2009-01-01

    In this study, we compared continuous cardiac output (CO) obtained from the femoral arterial pressure by simulation of an aortic input impedance model [model-simulated cardiac output (MCO)] to thermodilution cardiac output (TDCO) determined by bolus injection during liver transplantation. Both...... variables were measured in 39 adult patients (13 females) every 10th minute during liver transplant surgery. Paired measurements were compared during the 4 phases of surgery-dissection, anhepatic phase, early reperfusion (the first 15 minutes after reperfusion), and late reperfusion (15-60 minutes after......, and the mutual correlation coefficient was 0.812 (P < 0.001). This study indicates that during liver transplantation surgery, MCO reflects TDCO throughout the operation. Thus, for CO, this less invasive method appears to provide a reliable uninterrupted measurement during orthotopic liver...

  15. Hospital admissions and pharmacotherapy before out-of-hospital cardiac arrest according to age

    Weeke, Peter; Folke, Fredrik; Gislason, Gunnar H; Lippert, Freddy K; Olesen, Jonas B; Andersson, Charlotte; Wissenberg, Mads; Poulsen, Henrik E; Nielsen, Søren L; Køber, Lars; Torp-Pedersen, Christian

    2012-01-01

    BACKGROUND: The underlying etiology of sudden cardiac death varies with age and is likely to be reflected in type and number of healthcare contacts. We aimed to determine the specific type of healthcare contact shortly before out-of-hospital cardiac arrest (OHCA) across ages. METHODS: OHCA patients...... were identified in the nationwide Danish Cardiac Arrest Register and Copenhagen Medical Emergency Care Unit (2001-2006). We matched every OHCA patients with 10 controls on sex and age. Healthcare contacts were evaluated 30 days before event by individual-level-linkage of nationwide registers. RESULTS......: We identified 16,924 OHCA patients, median age 70.0 years (Q1-Q3: 59-80). OHCA patients had a higher number of hospitalizations and received more pharmacotherapy compared to the control population across all ages (p for difference 89) were...

  16. EVALUATION OF NEONATAL CARDIAC MURMURS

    Somaiah

    2014-09-01

    Full Text Available Cardiovascular malformations are the most common cause of congenital malformations, the diagnosis of which requires a close observation in the neonatal period. Early recognition of CHD is important in the neonatal period, as many of them may be fatal if undiagnosed and may require immediate intervention. The objectives of this study are to study the epidemiology of neonatal cardiac murmurs, to identify clinical characteristics which differentiate pathological murmur from functional murmurs and to assess the reliability of clinical evaluation in diagnosing CHD. Method of study included all neonates admitted to the NICU, postnatal ward, attending pediatric OPD or neonatal follow up clinic and were detected to have cardiac murmurs. It was a cross sectional study over a period of 16months. A clinical diagnosis was made based on history and clinical examination. Then Chest X-ray and ECG, Echocardiography was done in all neonates for confirmation of the diagnosis. These neonates were again examined daily till they were in hospital and during the follow-up visit at 6 weeks. The results of 70 neonates in this study conducted over a period of 24 months included the incidence of cardiac murmurs among intramural neonates which was 13.5 for 1000 live births. Most frequent symptom was fast breathing in 10(14.3% cases. VSD was the most common diagnosis clinically in 23 (33% babies. The most frequent Echo diagnosis was acyanotic complex congenital heart disease in 25(36% cases followed by 12(17% cases each of VSD and ASD respectively. Overall in our study 77.1% (54cases of the murmurs were diagnosed correctly and confirmed by Echocardiography The study concluded that it is possible to make clinical diagnosis in many cases of congenital heart diseases, the functional murmurs could be differentiated from those arising from structural heart disease and evaluation of the infants based only on murmurs, few congenital heart diseases can be missed.

  17. Sudden Cardiac Death and Post Cardiac Arrest Syndrome. An Overview

    Zima Endre

    2015-10-01

    Full Text Available A satisfactory neurologic outcome is the key factor for survival in patients with sudden cardiac death (SCD, however this is highly dependent on the haemodynamic status. Short term cardiopulmonary resuscitation and regained consciousness on the return of spontaneous circulation (ROSC is indicative of a better prognosis. The evaluation and treatment of SCD triggering factors and of underlying acute and chronic diseases will facilitate prevention and lower the risk of cardiac arrest. Long term CPR and a prolonged unconscious status after ROSC, in the Intensive Care Units or Coronary Care Units, indicates the need for specific treatment and supportive therapy including efforts to prevent hyperthermia. The prognosis of these patients is unpredictable within the first seventy two hours, due to unknown responses to therapeutic management and the lack of specific prognostic factors. Patients in these circumstances require the highest level of intensive care and aetiology driven treatment without any delay, independently of their coma state. Current guidelines sugest the use of multiple procedures in arriving at a diagnosis and prognosis of these critical cases.

  18. Accurate strand-specific quantification of viral RNA.

    Nicole E Plaskon

    Full Text Available The presence of full-length complements of viral genomic RNA is a hallmark of RNA virus replication within an infected cell. As such, methods for detecting and measuring specific strands of viral RNA in infected cells and tissues are important in the study of RNA viruses. Strand-specific quantitative real-time PCR (ssqPCR assays are increasingly being used for this purpose, but the accuracy of these assays depends on the assumption that the amount of cDNA measured during the quantitative PCR (qPCR step accurately reflects amounts of a specific viral RNA strand present in the RT reaction. To specifically test this assumption, we developed multiple ssqPCR assays for the positive-strand RNA virus o'nyong-nyong (ONNV that were based upon the most prevalent ssqPCR assay design types in the literature. We then compared various parameters of the ONNV-specific assays. We found that an assay employing standard unmodified virus-specific primers failed to discern the difference between cDNAs generated from virus specific primers and those generated through false priming. Further, we were unable to accurately measure levels of ONNV (- strand RNA with this assay when higher levels of cDNA generated from the (+ strand were present. Taken together, these results suggest that assays of this type do not accurately quantify levels of the anti-genomic strand present during RNA virus infectious cycles. However, an assay permitting the use of a tag-specific primer was able to distinguish cDNAs transcribed from ONNV (- strand RNA from other cDNAs present, thus allowing accurate quantification of the anti-genomic strand. We also report the sensitivities of two different detection strategies and chemistries, SYBR(R Green and DNA hydrolysis probes, used with our tagged ONNV-specific ssqPCR assays. Finally, we describe development, design and validation of ssqPCR assays for chikungunya virus (CHIKV, the recent cause of large outbreaks of disease in the Indian Ocean

  19. Quantitative assessment of mitral and aortic insufficiency from effective systemic ejection fraction measured by radiocardiography and cardiac chambers scanning

    Comparison between the effective systemic ejection fraction defined by radiocardiography and cardiac chambers scanning, and the whole left ventricular ejection fraction calculated by cineangiocardiography allows an accurate assessment of mitral and aortic regurgitation extent. In case of both mitral and aortic insufficiency, each regurgitation can be quantitatively dissociated by means of the aortic isotopic dilution curve recorded at the same time as the radiocardiogram

  20. Introduction to noninvasive cardiac mapping.

    Bear, Laura; Cuculich, Phillip S; Bernus, Olivier; Efimov, Igor; Dubois, Rémi

    2015-03-01

    From the dawn of the twentieth century, the electrocardiogram (ECG) has revolutionized the way clinical cardiology has been practiced, and it has become the cornerstone of modern medicine today. Driven by clinical and research needs for a more precise understanding of cardiac electrophysiology beyond traditional ECG, inverse solution electrocardiography has been developed, tested, and validated. This article outlines the important progress from ECG development, through more extensive measurement of body surface potentials, and the fundamental leap to solving the inverse problem of electrocardiography, with a focus on mathematical methods and experimental validation. PMID:25784020

  1. Autologous Transfusion in Cardiac Surgery

    Radmehr H

    2003-11-01

    Full Text Available Preoperative autologous blood donation is commonly used to reduce exposure to homologous blood transfusions among patients undergoing elective cardiac surgery. The aim of this study was to evaluate the effect of autologous transfusion on patients' hematocryte value, intra and postoperative blood loss, hospitalization time, the development of infective complications and other factors. Materials and Methods: Between June 2001 to April 2002, 208 patients were underwent cardiac surgery in cardiac surgery ward in Imam Khomeini Medical Center. One or more blood units donate from 104 Patients before cardiopulmonary bypass and heparin injection, and transfused to them after CPB and Protamin injection (autologous Group, group 1. 104 patients underwent cardiac surgery routinely (control group, group 2."nResults: Mean of age was 55.9±8.6 in group 1 and 56.6±9.3 in group 2 (P=NS. 73 male and 31 females were in group 1 and 79 males and 25 females were in group 2 (P=NS. Smoking, familial history, hyperlipidemia, diabetes mellitus, renal failure, hypertension, stroke, and history of myocardial infarction was similar in two groups."nSeverity of angina, urgency operation, number vessels disease, duration of cardiopulmonary bypass, duration of aortic cross clamp time, use of internal thoracic artery graft, and number of grafts was similar in both groups. Mean of bleeding post operation was 548 cc in group 1 and 803 cc in-group 2 (P=0.003. Bleeding that need to operation was 1.8% in group 1 and 8.6% in group 2 (P=0.002. Wound infection, mediastinitis, renal failure, ventilatory prolonged, stroke, need to Intra-aortic Balloon Pump (IABP, intraoperative bleeding, and hospital stay was similar in both groups. Mean of extubationt time was 10.2 hours in group 1 and 14.8 hours in group 2 (P=0.001."nConclusion: Preoperative and intra-operative donations are safe and continue to contribute uniquely to blood conservation, providing important options in comprehensive

  2. [Acute cardiac failure in pheochromocytoma.

    Jønler, Morten; Munk, Kim

    2008-01-01

    Pheochromocytoma (P) is an endocrine catecholamine-secreting tumor. Classical symptoms like hypertension, attacks of sweating, palpitations, headache and palor are related to catecholamine discharge. We provide a case of P in a 71 year-old man presenting with acute cardiac failure, severe reduction...... in left ventricular function and elevated myocardial enzymes. No coronary stenoses were found. The myocardium regained nearly normal systolic function in one and a half month. A renal P was laparoscopicaly removed. We discuss the pathophysiology of catecholamine cardiomyopathy. Udgivelsesdato: 2008...

  3. Cardiac leiomyosarcoma, a case report

    Andersen, Rikke; Kristensen, Bjarne W; Gill, Sabine

    2013-01-01

    In this case report we present the history of a patient admitted with recurrent pulmonary edema. Transesophageal chocardiography showed a tumour in the left atrium, occluding the ostium of the mitral valve and mimicking intermittent mitral stenosis. Cardiac surgery followed by pathological...... examination revealed that the tumour was a leiomyosarcoma. Images from the echocardiography as well as the pathological findings are shown and discussed. The present case report illustrates that atrial tumors comprise also sarcomas, suggesting the use of careful, rapid diagnostic procedures and treatment to...

  4. MR-guided cardiac catheterization

    Exposing young children to X-rays is a source of concern, since the effect is cumulative and it is important to avoid adding to their lifetime dose. This becomes particularly significant in the case of congenital heart disease, as the patients often need life-long monitoring and successive interventions. Alternative imaging techniques are needed in order to eliminate or limit X-ray exposure. This article demonstrates the feasibility of MR-guided cardiac catheterization using passive device visualization. The procedures are performed in a Philips XMR suite, where all or a substantial part of the catheterization procedure is performed with MR guidance, resulting in significant dose savings. (orig.)

  5. Assessment of cardiac sympathetic nerve integrity with positron emission tomography

    Raffel, David M. E-mail: raffel@umich.edu; Wieland, Donald M

    2001-07-01

    The autonomic nervous system plays a critical role in the regulation of cardiac function. Abnormalities of cardiac innervation have been implicated in the pathophysiology of many heart diseases, including sudden cardiac death and congestive heart failure. In an effort to provide clinicians with the ability to regionally map cardiac innervation, several radiotracers for imaging cardiac sympathetic neurons have been developed. This paper reviews the development of neuronal imaging agents and discusses their emerging role in the noninvasive assessment of cardiac sympathetic innervation.

  6. Focused Cardiac Ultrasound Diagnosis of Cor Triatriatum Sinistrum in Pediatric Cardiac Arrest

    Thompson Kehrl,

    2015-10-01

    Full Text Available Cardiac arrest in the adolescent population secondary to congenital heart disease (CHD is rare. Focused cardiac ultrasound (FoCUS in the emergency department (ED can yield important clinical information, aid in resuscitative efforts during cardiac arrest and is commonly integrated into the evaluation of patients with pulseless electrical activity (PEA. We report a case of pediatric cardiac arrest in which FoCUS was used to diagnose a critical CHD known as cor triatriatum sinistrum as the likely cause for PEA cardiac arrest and help direct ED resuscitation.

  7. The Cardiac Conduction System: Generation and Conduction of the Cardiac Impulse.

    Kennedy, Alan; Finlay, Dewar D; Guldenring, Daniel; Bond, Raymond; Moran, Kieran; McLaughlin, James

    2016-09-01

    In this article, the authors outline the key components behind the automated generation of the cardiac impulses and the effect these impulses have on cardiac myocytes. Also, a description of the key components of the normal cardiac conduction system is provided, including the sinoatrial node, the atrioventricular node, the His bundle, the bundle branches, and the Purkinje network. Finally, an outline of how each stage of the cardiac conduction system is represented on the electrocardiogram is described, allowing the reader of the electrocardiogram to translate background information about the normal cardiac conduction system to everyday clinical practice. PMID:27484656

  8. Filters in 2D and 3D Cardiac SPECT Image Processing

    Maria Lyra

    2014-01-01

    Full Text Available Nuclear cardiac imaging is a noninvasive, sensitive method providing information on cardiac structure and physiology. Single photon emission tomography (SPECT evaluates myocardial perfusion, viability, and function and is widely used in clinical routine. The quality of the tomographic image is a key for accurate diagnosis. Image filtering, a mathematical processing, compensates for loss of detail in an image while reducing image noise, and it can improve the image resolution and limit the degradation of the image. SPECT images are then reconstructed, either by filter back projection (FBP analytical technique or iteratively, by algebraic methods. The aim of this study is to review filters in cardiac 2D, 3D, and 4D SPECT applications and how these affect the image quality mirroring the diagnostic accuracy of SPECT images. Several filters, including the Hanning, Butterworth, and Parzen filters, were evaluated in combination with the two reconstruction methods as well as with a specified MatLab program. Results showed that for both 3D and 4D cardiac SPECT the Butterworth filter, for different critical frequencies and orders, produced the best results. Between the two reconstruction methods, the iterative one might be more appropriate for cardiac SPECT, since it improves lesion detectability due to the significant improvement of image contrast.

  9. Wild-Type Transthyretin Cardiac Amyloidosis: Novel Insights From Advanced Imaging.

    Narotsky, David L; Castano, Adam; Weinsaft, Jonathan W; Bokhari, Sabahat; Maurer, Mathew S

    2016-09-01

    Amyloidosis is caused by extracellular deposition of abnormal protein fibrils, resulting in destruction of tissue architecture and impairment of organ function. The most common forms of systemic amyloidosis are light-chain and transthyretin-related (ATTR). ATTR can result from an autosomal dominant hereditary transmission of mutated genes in the transthyretin or from a wild-type form of disease (ATTRwt), previously known as senile cardiac amyloidosis. With the aging of the worldwide population, ATTRwt will emerge as the most common type of cardiac amyloidosis that clinicians encounter. Diagnosis of systemic amyloidosis is often delayed, either because of the false assumption that it is a rare disease, or because of misdiagnosis as a result of mistaking it with other conditions. Clinicians must integrate clinical clues from history, physical examination, and common diagnostic tests to raise suspicion for ATTRwt. The historical gold standard for diagnosis of cardiac amyloid is endomyocardial biopsy analysis with pathological distinction of precursor protein type, but this method often results in delayed diagnosis because of the limited availability of expertise to perform and interpret the endomyocardial biopsy specimen. Emerging noninvasive imaging modalities provide easier, accurate screening for ATTRwt. These modalities include advanced echocardiography, using strain imaging and the myocardial contraction fraction; nuclear scintigraphy, which can differentiate between ATTR and light-chain cardiac amyloid; and cardiac magnetic resonance imaging, using extracellular volume measurement, late gadolinium enhancement, and distinct T1 mapping. These novel approaches reveal insights into the prevalence, clinical course, morphological effects, and prognosis of ATTRwt. PMID:27568874

  10. Active cardiac model and its application on structure detection from early fetal ultrasound sequences.

    Deng, Yinhui; Wang, Yuanyuan; Shen, Yuzhong; Chen, Ping

    2012-04-01

    The structure of an early fetal heart provides vital information for the diagnosis of fetus defects. However, early fetal hearts are difficult to detect due to their relatively small size and the low signal-to-noise ratio of ultrasound images. In this paper, a novel method is proposed for automatic detection of early fetal cardiac structure from ultrasound images. The proposed method consists of two major parts which are the preprocessing phase and the active cardiac model: (1) The preprocessing phase consists of two sub-steps. (a) The region of interest is first automatically selected based on an accumulated motion image, which is able to represent the motion information of the fetal heart more accurately. (b) Then by combining Rayleigh-trimmed filter and anisotropic diffusion in 3-dimensional space, a despeckling method is developed to suppress the speckle noise and emphasize the motion information for subsequent cardiac structure detection. (2) The active cardiac model is proposed for the detection of fetal heart structure, which is a key contribution of this paper. It takes into account both the structure and motion information of fetal hearts simultaneously. Both learning and inference of the active cardiac model are described in the paper. Experiments on seven ultrasound sequences demonstrate the effectiveness of the proposed method. PMID:21620676

  11. Focused Cardiac Ultrasound Using a Pocket-Size Device in the Emergency Room

    Cardiovascular urgencies are frequent reasons for seeking medical care. Prompt and accurate medical diagnosis is critical to reduce the morbidity and mortality of these conditions. To evaluate the use of a pocket-size echocardiography in addition to clinical history and physical exam in a tertiary medical emergency care. One hundred adult patients without known cardiac or lung diseases who sought emergency care with cardiac complaints were included. Patients with ischemic changes in the electrocardiography or fever were excluded. A focused echocardiography with GE Vscan equipment was performed after the initial evaluation in the emergency room. Cardiac chambers dimensions, left and right ventricular systolic function, intracardiac flows with color, pericardium, and aorta were evaluated. The mean age was 61 ± 17 years old. The patient complaint was chest pain in 51 patients, dyspnea in 32 patients, arrhythmia to evaluate the left ventricular function in ten patients, hypotension/dizziness in five patients and edema in one patient. In 28 patients, the focused echocardiography allowed to confirm the initial diagnosis: 19 patients with heart failure, five with acute coronary syndrome, two with pulmonary embolism and two patients with cardiac tamponade. In 17 patients, the echocardiography changed the diagnosis: ten with suspicious of heart failure, two with pulmonary embolism suspicious, two with hypotension without cause, one suspicious of acute coronary syndrome, one of cardiac tamponade and one of aortic dissection. The focused echocardiography with pocket-size equipment in the emergency care may allow a prompt diagnosis and, consequently, an earlier initiation of the therapy

  12. Image registration and analysis for quantitative myocardial perfusion: application to dynamic circular cardiac CT

    Large area detector computed tomography systems with fast rotating gantries enable volumetric dynamic cardiac perfusion studies. Prospectively, ECG-triggered acquisitions limit the data acquisition to a predefined cardiac phase and thereby reduce x-ray dose and limit motion artefacts. Even in the case of highly accurate prospective triggering and stable heart rate, spatial misalignment of the cardiac volumes acquired and reconstructed per cardiac cycle may occur due to small motion pattern variations from cycle to cycle. These misalignments reduce the accuracy of the quantitative analysis of myocardial perfusion parameters on a per voxel basis. An image-based solution to this problem is elastic 3D image registration of dynamic volume sequences with variable contrast, as it is introduced in this contribution. After circular cone-beam CT reconstruction of cardiac volumes covering large areas of the myocardial tissue, the complete series is aligned with respect to a chosen reference volume. The results of the registration process and the perfusion analysis with and without registration are evaluated quantitatively in this paper. The spatial alignment leads to improved quantification of myocardial perfusion for three different pig data sets.

  13. Focused Cardiac Ultrasound Using a Pocket-Size Device in the Emergency Room

    Mancuso, Frederico José Neves, E-mail: frederico.mancuso@grupofleury.com.br [Disciplina de Cardiologia - Escola Paulista de Medicina - Universidade Federal de São Paulo (Unifesp), São Paulo, SP (Brazil); Disciplina de Medicina de Urgência - Escola Paulista de Medicina - Universidade Federal de São Paulo (Unifesp), São Paulo, SP (Brazil); Siqueira, Vicente Nicoliello; Moisés, Valdir Ambrósio [Disciplina de Cardiologia - Escola Paulista de Medicina - Universidade Federal de São Paulo (Unifesp), São Paulo, SP (Brazil); Gois, Aécio Flavio Teixeira [Disciplina de Medicina de Urgência - Escola Paulista de Medicina - Universidade Federal de São Paulo (Unifesp), São Paulo, SP (Brazil); Paola, Angelo Amato Vincenzo de; Carvalho, Antonio Carlos Camargo; Campos, Orlando [Disciplina de Cardiologia - Escola Paulista de Medicina - Universidade Federal de São Paulo (Unifesp), São Paulo, SP (Brazil)

    2014-12-15

    Cardiovascular urgencies are frequent reasons for seeking medical care. Prompt and accurate medical diagnosis is critical to reduce the morbidity and mortality of these conditions. To evaluate the use of a pocket-size echocardiography in addition to clinical history and physical exam in a tertiary medical emergency care. One hundred adult patients without known cardiac or lung diseases who sought emergency care with cardiac complaints were included. Patients with ischemic changes in the electrocardiography or fever were excluded. A focused echocardiography with GE Vscan equipment was performed after the initial evaluation in the emergency room. Cardiac chambers dimensions, left and right ventricular systolic function, intracardiac flows with color, pericardium, and aorta were evaluated. The mean age was 61 ± 17 years old. The patient complaint was chest pain in 51 patients, dyspnea in 32 patients, arrhythmia to evaluate the left ventricular function in ten patients, hypotension/dizziness in five patients and edema in one patient. In 28 patients, the focused echocardiography allowed to confirm the initial diagnosis: 19 patients with heart failure, five with acute coronary syndrome, two with pulmonary embolism and two patients with cardiac tamponade. In 17 patients, the echocardiography changed the diagnosis: ten with suspicious of heart failure, two with pulmonary embolism suspicious, two with hypotension without cause, one suspicious of acute coronary syndrome, one of cardiac tamponade and one of aortic dissection. The focused echocardiography with pocket-size equipment in the emergency care may allow a prompt diagnosis and, consequently, an earlier initiation of the therapy.

  14. Accurate basis set truncation for wavefunction embedding

    Barnes, Taylor A.; Goodpaster, Jason D.; Manby, Frederick R.; Miller, Thomas F.

    2013-07-01

    Density functional theory (DFT) provides a formally exact framework for performing embedded subsystem electronic structure calculations, including DFT-in-DFT and wavefunction theory-in-DFT descriptions. In the interest of efficiency, it is desirable to truncate the atomic orbital basis set in which the subsystem calculation is performed, thus avoiding high-order scaling with respect to the size of the MO virtual space. In this study, we extend a recently introduced projection-based embedding method [F. R. Manby, M. Stella, J. D. Goodpaster, and T. F. Miller III, J. Chem. Theory Comput. 8, 2564 (2012)], 10.1021/ct300544e to allow for the systematic and accurate truncation of the embedded subsystem basis set. The approach is applied to both covalently and non-covalently bound test cases, including water clusters and polypeptide chains, and it is demonstrated that errors associated with basis set truncation are controllable to well within chemical accuracy. Furthermore, we show that this approach allows for switching between accurate projection-based embedding and DFT embedding with approximate kinetic energy (KE) functionals; in this sense, the approach provides a means of systematically improving upon the use of approximate KE functionals in DFT embedding.

  15. Accurate pose estimation for forensic identification

    Merckx, Gert; Hermans, Jeroen; Vandermeulen, Dirk

    2010-04-01

    In forensic authentication, one aims to identify the perpetrator among a series of suspects or distractors. A fundamental problem in any recognition system that aims for identification of subjects in a natural scene is the lack of constrains on viewing and imaging conditions. In forensic applications, identification proves even more challenging, since most surveillance footage is of abysmal quality. In this context, robust methods for pose estimation are paramount. In this paper we will therefore present a new pose estimation strategy for very low quality footage. Our approach uses 3D-2D registration of a textured 3D face model with the surveillance image to obtain accurate far field pose alignment. Starting from an inaccurate initial estimate, the technique uses novel similarity measures based on the monogenic signal to guide a pose optimization process. We will illustrate the descriptive strength of the introduced similarity measures by using them directly as a recognition metric. Through validation, using both real and synthetic surveillance footage, our pose estimation method is shown to be accurate, and robust to lighting changes and image degradation.

  16. Accurate determination of characteristic relative permeability curves

    Krause, Michael H.; Benson, Sally M.

    2015-09-01

    A recently developed technique to accurately characterize sub-core scale heterogeneity is applied to investigate the factors responsible for flowrate-dependent effective relative permeability curves measured on core samples in the laboratory. The dependency of laboratory measured relative permeability on flowrate has long been both supported and challenged by a number of investigators. Studies have shown that this apparent flowrate dependency is a result of both sub-core scale heterogeneity and outlet boundary effects. However this has only been demonstrated numerically for highly simplified models of porous media. In this paper, flowrate dependency of effective relative permeability is demonstrated using two rock cores, a Berea Sandstone and a heterogeneous sandstone from the Otway Basin Pilot Project in Australia. Numerical simulations of steady-state coreflooding experiments are conducted at a number of injection rates using a single set of input characteristic relative permeability curves. Effective relative permeability is then calculated from the simulation data using standard interpretation methods for calculating relative permeability from steady-state tests. Results show that simplified approaches may be used to determine flowrate-independent characteristic relative permeability provided flow rate is sufficiently high, and the core heterogeneity is relatively low. It is also shown that characteristic relative permeability can be determined at any typical flowrate, and even for geologically complex models, when using accurate three-dimensional models.

  17. Accurate shear measurement with faint sources

    Zhang, Jun; Foucaud, Sebastien [Center for Astronomy and Astrophysics, Department of Physics and Astronomy, Shanghai Jiao Tong University, 955 Jianchuan road, Shanghai, 200240 (China); Luo, Wentao, E-mail: betajzhang@sjtu.edu.cn, E-mail: walt@shao.ac.cn, E-mail: foucaud@sjtu.edu.cn [Key Laboratory for Research in Galaxies and Cosmology, Shanghai Astronomical Observatory, Nandan Road 80, Shanghai, 200030 (China)

    2015-01-01

    For cosmic shear to become an accurate cosmological probe, systematic errors in the shear measurement method must be unambiguously identified and corrected for. Previous work of this series has demonstrated that cosmic shears can be measured accurately in Fourier space in the presence of background noise and finite pixel size, without assumptions on the morphologies of galaxy and PSF. The remaining major source of error is source Poisson noise, due to the finiteness of source photon number. This problem is particularly important for faint galaxies in space-based weak lensing measurements, and for ground-based images of short exposure times. In this work, we propose a simple and rigorous way of removing the shear bias from the source Poisson noise. Our noise treatment can be generalized for images made of multiple exposures through MultiDrizzle. This is demonstrated with the SDSS and COSMOS/ACS data. With a large ensemble of mock galaxy images of unrestricted morphologies, we show that our shear measurement method can achieve sub-percent level accuracy even for images of signal-to-noise ratio less than 5 in general, making it the most promising technique for cosmic shear measurement in the ongoing and upcoming large scale galaxy surveys.

  18. End-expiration respiratory gating for a high-resolution stationary cardiac SPECT system

    Chan, Chung; Harris, Mark; Le, Max; Biondi, James; Grobshtein, Yariv; Liu, Yi-Hwa; Sinusas, Albert J.; Liu, Chi

    2014-10-01

    the patient with defect. The results showed that the proposed methods can effectively reduce motion blur in the images caused by both respiratory and cardiac motions, which may lead to more accurate defect detection and quantifications. This approach can be easily adapted in routine clinical practice on currently available commercial systems.

  19. End-expiration respiratory gating for a high-resolution stationary cardiac SPECT system

    noise on the patient with defect. The results showed that the proposed methods can effectively reduce motion blur in the images caused by both respiratory and cardiac motions, which may lead to more accurate defect detection and quantifications. This approach can be easily adapted in routine clinical practice on currently available commercial systems. (paper)

  20. Cardiac cell proliferation assessed by EdU, a novel analysis of cardiac regeneration.

    Zeng, Bin; Tong, Suiyang; Ren, Xiaofeng; Xia, Hao

    2016-08-01

    Emerging evidence suggests that mammalian hearts maintain the capacity for cardiac regeneration. Rapid and sensitive identification of cardiac cellular proliferation is prerequisite for understanding the underlying mechanisms and strategies of cardiac regeneration. The following immunologically related markers of cardiac cells were analyzed: cardiac transcription factors Nkx2.5 and Gata 4; specific marker of cardiomyocytes TnT; endothelial cell marker CD31; vascular smooth muscle marker smooth muscle myosin IgG; cardiac resident stem cells markers IsL1, Tbx18, and Wt1. Markers were co-localized in cardiac tissues of embryonic, neonatal, adult, and pathological samples by 5-ethynyl-2'-deoxyuridine (EdU) staining. EdU was also used to label isolated neonatal cardiomyocytes in vitro. EdU robustly labeled proliferating cells in vitro and in vivo, co-immunostaining with different cardiac cells markers. EdU can rapidly and sensitively label proliferating cardiac cells in developmental and pathological states. Cardiac cell proliferation assessed by EdU is a novel analytical tool for investigating the mechanism and strategies of cardiac regeneration in response to injury. PMID:25480318

  1. Clinical study of cardiac diseases during pregnancy

    Amitha Vijay Kamat

    2016-03-01

    Conclusions: Cardiac diseases in pregnancy constitute high risk pregnancy and require special attention during antepartum, intrapartum and postpartum period. Rheumatic heart disease was the major contribution of cardiac diseases in pregnancy and is seen to be associated with increased maternal morbidity. [Int J Reprod Contracept Obstet Gynecol 2016; 5(3.000: 855-859

  2. Cardiac hydatid cyst revealed by ventricular tachycardia

    Ibn Elhadj, Zied; Boukhris, Marouane; Kammoun, Ikram; Halima, Afef Ben; Addad, Faouzi; Kachboura, Salem

    2013-01-01

    Hydatid disease is a human parasitic infestation caused by the larval stage of Echinococcus Granulosus. The liver and the lungs are the most common locations. Cardiac involvement is rare and accounts for 0.5–2% of all hydatid disease. We report an unusual presentation of cardiac hydatid cyst revealed by ventricular tachycardia in a patient with a history of cerebral hydatid cyst.

  3. Cardiac arrhythmia classification using autoregressive modeling

    Srinivasan Narayanan; Ge Dingfei; Krishnan Shankar M

    2002-01-01

    Abstract Background Computer-assisted arrhythmia recognition is critical for the management of cardiac disorders. Various techniques have been utilized to classify arrhythmias. Generally, these techniques classify two or three arrhythmias or have significantly large processing times. A simpler autoregressive modeling (AR) technique is proposed to classify normal sinus rhythm (NSR) and various cardiac arrhythmias including atrial premature contraction (APC), premature ventricular contraction (...

  4. Cardiac Diseases in People with Intellectual Disability

    van den Akker, M.; Maaskant, M. A.; van der Meijden, R. J. M.

    2006-01-01

    Background: In people with ID there is more morbidity than in the general population, including cardiac diseases. Dutch figures on this subject are scarce. Methods: Descriptive study of the prevalence of cardiac diseases in 436 residential clients in Echt, the Netherlands, and comparisons between men and women, age groups, and level and aetiology…

  5. CARDIAC SIZE IN THE SUPINE CHESTFILM

    VANDERJAGT, EJ; SMITS, HJ

    1992-01-01

    The aim of this study was to find a normal value for the cardiac size in the supine position because such a standard is hardly known in the literature. Cardiac size in the erect and supine positions were compared in 165 patients in whom both chest radiographs were performed prior to kidney transplan

  6. The Western Denmark Cardiac Computed Tomography Registry

    Nielsen, Lene Hüche; Nørgaard, Bjarne Linde; Tilsted, Hans Henrik;

    2015-01-01

    BACKGROUND: As a subregistry to the Western Denmark Heart Registry (WDHR), the Western Denmark Cardiac Computed Tomography Registry (WDHR-CCTR) is a clinical database established in 2008 to monitor and improve the quality of cardiac computed tomography (CT) in Western Denmark. OBJECTIVE: We...

  7. Fetal cardiac interventions: clinical and experimental research.

    Yuan, Shi-Min; Humuruola, Gulimila

    2016-01-01

    Fetal cardiac interventions for congenital heart diseases may alleviate heart dysfunction, prevent them evolving into hypoplastic left heart syndrome, achieve biventricular outcome and improve fetal survival. Candidates for clinical fetal cardiac interventions are now restricted to cases of critical aortic valve stenosis with evolving hypoplastic left heart syndrome, pulmonary atresia with an intact ventricular septum and evolving hypoplastic right heart syndrome, and hypoplastic left heart syndrome with an intact or highly restrictive atrial septum as well as fetal heart block. The therapeutic options are advocated as prenatal aortic valvuloplasty, pulmonary valvuloplasty, creation of interatrial communication and fetal cardiac pacing. Experimental research on fetal cardiac intervention involves technical modifications of catheter-based cardiac clinical interventions and open fetal cardiac bypass that cannot be applied in human fetuses for the time being. Clinical fetal cardiac interventions are plausible for midgestation fetuses with the above-mentioned congenital heart defects. The technical success, biventricular outcome and fetal survival are continuously being improved in the conditions of the sophisticated multidisciplinary team, equipment, techniques and postnatal care. Experimental research is laying the foundations and may open new fields for catheter-based clinical techniques. In the present article, the clinical therapeutic options and experimental fetal cardiac interventions are described. PMID:27279868

  8. Acute cardiac failure in neuroleptic malignant syndrome.

    Sparrow, Patrick

    2012-02-03

    We present a case of rapid onset acute cardiac failure developing as part of neuroleptic malignant syndrome in a 35-year-old woman following treatment with thioridazine and lithium. Post mortem histology of cardiac and skeletal muscle showed similar changes of focal cellular necrosis and vacuolation suggesting a common disease process.

  9. Cardiac Vagal Regulation and Early Peer Status

    Graziano, Paulo A.; Keane, Susan P.; Calkins, Susan D.

    2007-01-01

    A sample of 341 5 1/2-year-old children participating in an ongoing longitudinal study was the focus of a study on the relation between cardiac vagal regulation and peer status. To assess cardiac vagal regulation, resting measures of respiratory sinus arrhythmia (RSA) and RSA change (suppression) to 3 cognitively and emotionally challenging tasks…

  10. Coagulopathy and hemostatic monitoring in cardiac surgery

    Johansson, Pär I; Sølbeck, Sacha; Genet, Gustav; Stensballe, Jakob; Ostrowski, Sisse R

    2012-01-01

    Cardiac surgery with cardiopulmonary bypass (CPB) causes severe derangements in the hemostatic system, which in turn puts the patient at risks of microvascular bleeding. Excessive transfusion and surgical re-exploration after cardiac surgery are potentially associated with a number of adverse...

  11. Athletes at Risk for Sudden Cardiac Death

    Subasic, Kim

    2010-01-01

    High school athletes represent the largest group of individuals affected by sudden cardiac death, with an estimated incidence of once or twice per week. Structural cardiovascular abnormalities are the most frequent cause of sudden cardiac death. Athletes participating in basketball, football, track, soccer, baseball, and swimming were found to…

  12. Conditional shape models for cardiac motion estimation

    Metz, C.T.; Baka, N.; Kirisli, H.A.;

    2010-01-01

    We propose a conditional statistical shape model to predict patient specific cardiac motion from the 3D end-diastolic CTA scan. The model is built from 4D CTA sequences by combining atlas based segmentation and 4D registration. Cardiac motion estimation is, for example, relevant in the dynamic al...

  13. Preoperative respiratory physical therapy in cardiac surgery

    Hulzebos, H.J.

    2006-01-01

    Cardiac surgery is one of the most common surgical procedures and accounts for more resources expended in cardiovascular medicine than any other single procedure. Because cardiac surgery involves sternal incision and cardiopulmonary bypass, patients usually have a restricted respiratory function in

  14. Cardiac MRI of the athlete's heart

    Prakken, N.H.J.

    2010-01-01

    The increase in pre-participation cardiovascular screening using the Lausanne protocol will ultimately lead to an increased use of cardiac MRI and MDCT in the cardiovascular work-up of athletes. The role of cardiac MRI is well established in the evaluation of cardiomyopathies, myocarditis, aortic st

  15. Hemodynamics driven cardiac valve morphogenesis.

    Steed, Emily; Boselli, Francesco; Vermot, Julien

    2016-07-01

    Mechanical forces are instrumental to cardiovascular development and physiology. The heart beats approximately 2.6 billion times in a human lifetime and heart valves ensure that these contractions result in an efficient, unidirectional flow of the blood. Composed of endocardial cells (EdCs) and extracellular matrix (ECM), cardiac valves are among the most mechanically challenged structures of the body both during and after their development. Understanding how hemodynamic forces modulate cardiovascular function and morphogenesis is key to unraveling the relationship between normal and pathological cardiovascular development and physiology. Most valve diseases have their origins in embryogenesis, either as signs of abnormal developmental processes or the aberrant re-expression of fetal gene programs normally quiescent in adulthood. Here we review recent discoveries in the mechanobiology of cardiac valve development and introduce the latest technologies being developed in the zebrafish, including live cell imaging and optical technologies, as well as modeling approaches that are currently transforming this field. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel. PMID:26608609

  16. Cardiac Rehabilitation in Older Adults.

    Schopfer, David W; Forman, Daniel E

    2016-09-01

    The biology of aging and the pathophysiology of cardiovascular disease (CVD) overlap, with the effect that CVD is endemic in the growing population of older adults. Moreover, CVD in older adults is usually complicated by age-related complexities, including multimorbidity, polypharmacy, frailty, and other intricacies that add to the risks of ambiguous symptoms, deconditioning, iatrogenesis, falls, disability, and other challenges. Cardiac rehabilitation (CR) is a comprehensive lifestyle program that can have particular benefit for older patients with cardiovascular conditions. Although CR was originally designed primarily as an exercise training program for younger adults after a myocardial infarction or coronary artery bypass surgery, it has evolved as a comprehensive lifestyle program (promoting physical activity as well as education, diet, risk reduction, and adherence) for a broader range of CVD (coronary heart disease, heart failure, and valvular heart disease). It provides a valuable opportunity to address and moderate many of the challenges pertinent for the large and growing population of older adults with CVD. Cardiac rehabilitation promotes physical function (cardiorespiratory fitness as well as strength and balance) that helps overcome disease and deconditioning as well as related vulnerabilities such as disability, frailty, and falls. Similarly, CR facilitates education, monitoring, and guidance to reduce iatrogenesis and promote adherence. Furthermore, CR fosters cognition, socialization, and independence in older patients. Yet despite all its conceptual benefits, CR is significantly underused in older populations. This review discusses benefits and the paradoxical underuse of CR, as well as evolving models of care that may achieve greater application and efficacy. PMID:27297002

  17. Lipid partitioning during cardiac stress.

    Kolwicz, Stephen C

    2016-10-01

    It is well documented that fatty acids serve as the primary fuel substrate for the contracting myocardium. However, extensive research has identified significant changes in the myocardial oxidation of fatty acids during acute or chronic cardiac stress. As a result, the redistribution or partitioning of fatty acids due to metabolic derangements could have biological implications. Fatty acids can be stored as triacylglycerols, serve as critical components for biosynthesis of phospholipid membranes, and form the potent signaling molecules, diacylglycerol and ceramides. Therefore, the contribution of lipid metabolism to health and disease is more intricate than a balance of uptake and oxidation. In this review, the available data regarding alterations that occur in endogenous cardiac lipid pathways during the pathological stressors of ischemia-reperfusion and pathological hypertrophy/heart failure are highlighted. In addition, changes in endogenous lipids observed in exercise training models are presented for comparison. This article is part of a Special Issue entitled: Heart Lipid Metabolism edited by G.D. Lopaschuk. PMID:27040509

  18. A Framework for Teacher Reflectivity.

    Stanley, Claire

    1998-01-01

    Proposes a framework for teacher reflection based on a longitudinal study of the development of six experienced second-language teachers who attempted to implement reflection and reflective action into their teaching practice. The resulting framework included several phases in the development of reflective teaching: engaging with reflection,…

  19. Imaging of the atria and cardiac conduction system – from experiment to computer modelling

    Hao, Guoliang

    2013-01-01

    Background: Experimental mapping and computer modelling provide important platforms to study the fundamental mechanisms underlying normal and abnormal activation of the heart. However, accurate computer modelling requires detailed anatomical models and needs support and validation from experimental data. Aims: 1) Construction of detailed anatomical heart models with the cardiac conduction system (CCS). 2) Mapping of the electrical activation sequence in rabbit atria to support and validate co...

  20. 1093 Automatic delineation of endo- and epicardial contours in late-enhancement cardiac MR images

    Hautvast Gilion; Mory Benoit; Fradkin Maxim; Ciofolo Cybele; Breeuwer Marcel

    2008-01-01

    The authors would like to acknowledge BioMed Central for allowing open access to this paper. Please download the publisher version by using http://jcmr-online.com/content/10/S1/A218 International audience We propose a novel method to automatically delineate the endo- and epicardial contours in late-enhancement short-axis cardiac MR images in order to provide an automatic, accurate quantitative viability assessment.

  1. [Rhythm disorders and cardiac crypto-malformations].

    Davy, J M; Raczka, F; Cung, T T; Combes, N; Bortone, A; Gaty, D

    2005-12-01

    Faced with a cardiac arrhythmia occuring in an apparently healthy heart, it is necessary to perform an anatomical investigation to detect any unsuspected anomalies. Congenital cardiopathy must certainly be excluded, as this is often responsible for rhythm disorders and/or cardiac conduction defects. Similarly, any acquired conditions, cardiomyopathy, or cardiac tumour must be sought. However, the possibility should always be considered of a minimal congenital malformation, which could be repsonsible for: any type of cardiac arrhythmia: rhythm disorder or conduction defect at the atrial, junctional or ventricular level, with a benign or serious prognosis. Unexpected therapeutic difficulties during radiofrequency ablation procedures or at implantation of pacemakers or defibrillators. Together with rhythm studies, the investigation of choice is high quality imaging, either the classic left or right angiography or the more modern cardiac CT or intracardiac mapping. PMID:16433240

  2. Causes of sudden cardiac death in athletes

    Popović Dejana

    2007-01-01

    Full Text Available Introduction Sudden cardiac death in athletes is a growing problem, despite the huge existing knowledge in medicine and sports. Effects of vigorous physical activity In response to vigorous physical activity, the body undergoes profound morphologic and functional changes. These changes are usually healthy, but sometimes may gravitate to some cardiac diseases. But still, most sudden cardiac deaths are due to previous unknown diseases. Causes of sudden cardiac death The most common cause of sudden cardiac death in athletes is hypertrophic cardiomyopathy. Other reasons are congenital coronary artery anomalies, myocarditis, dilatative cardiomyopathy, arrhythmogenic cardiomyopathy of the right ventricle, sarcoidosis, mitral valve prolapse, aortic valve stenosis, atherosclerosis, long QT syndrome, and blunt impact to the chest. Conclusion Bearing in mind the above mentioned, more frequent physical examinations of athletes are recommended.

  3. Facilitating management learning: Developing critical reflection through reflective tools

    Gray, David E

    2007-01-01

    The aim of this article is to explore how the practice of critical reflection within a management learning process can be facilitated through the application of reflective processes and tools. A distinction is drawn between reflection as a form of individual development (of, say, the reflective practitioner), and critical reflection as a route to collective action and a component of organizational learning and change. Critical reflection, however, is not a process that comes naturally to many...

  4. Accurate Telescope Mount Positioning with MEMS Accelerometers

    Mészáros, László; Pál, András; Csépány, Gergely

    2014-01-01

    This paper describes the advantages and challenges of applying microelectromechanical accelerometer systems (MEMS accelerometers) in order to attain precise, accurate and stateless positioning of telescope mounts. This provides a completely independent method from other forms of electronic, optical, mechanical or magnetic feedback or real-time astrometry. Our goal is to reach the sub-arcminute range which is well smaller than the field-of-view of conventional imaging telescope systems. Here we present how this sub-arcminute accuracy can be achieved with very cheap MEMS sensors and we also detail how our procedures can be extended in order to attain even finer measurements. In addition, our paper discusses how can a complete system design be implemented in order to be a part of a telescope control system.

  5. Accurate estimation of indoor travel times

    Prentow, Thor Siiger; Blunck, Henrik; Stisen, Allan;

    2014-01-01

    the InTraTime method for accurately estimating indoor travel times via mining of historical and real-time indoor position traces. The method learns during operation both travel routes, travel times and their respective likelihood---both for routes traveled as well as for sub-routes thereof. InTraTime...... allows to specify temporal and other query parameters, such as time-of-day, day-of-week or the identity of the traveling individual. As input the method is designed to take generic position traces and is thus interoperable with a variety of indoor positioning systems. The method's advantages include...... a minimal-effort setup and self-improving operations due to unsupervised learning---as it is able to adapt implicitly to factors influencing indoor travel times such as elevators, rotating doors or changes in building layout. We evaluate and compare the proposed InTraTime method to indoor adaptions...

  6. Accurate sky background modelling for ESO facilities

    Full text: Ground-based measurements like e.g. high resolution spectroscopy are heavily influenced by several physical processes. Amongst others, line absorption/ emission, air glow by OH molecules, and scattering of photons within the earth's atmosphere make observations in particular from facilities like the future European extremely large telescope a challenge. Additionally, emission from unresolved extrasolar objects, the zodiacal light, the moon and even thermal emission from the telescope and the instrument contribute significantly to the broad band background over a wide wavelength range. In our talk we review these influences and give an overview on how they can be accurately modeled for increasing the overall precision of spectroscopic and imaging measurements. (author)

  7. Toward Accurate and Quantitative Comparative Metagenomics.

    Nayfach, Stephen; Pollard, Katherine S

    2016-08-25

    Shotgun metagenomics and computational analysis are used to compare the taxonomic and functional profiles of microbial communities. Leveraging this approach to understand roles of microbes in human biology and other environments requires quantitative data summaries whose values are comparable across samples and studies. Comparability is currently hampered by the use of abundance statistics that do not estimate a meaningful parameter of the microbial community and biases introduced by experimental protocols and data-cleaning approaches. Addressing these challenges, along with improving study design, data access, metadata standardization, and analysis tools, will enable accurate comparative metagenomics. We envision a future in which microbiome studies are replicable and new metagenomes are easily and rapidly integrated with existing data. Only then can the potential of metagenomics for predictive ecological modeling, well-powered association studies, and effective microbiome medicine be fully realized. PMID:27565341

  8. Accurate valence band width of diamond

    An accurate width is determined for the valence band of diamond by imaging photoelectron momentum distributions for a variety of initial- and final-state energies. The experimental result of 23.0±0.2 eV2 agrees well with first-principles quasiparticle calculations (23.0 and 22.88 eV) and significantly exceeds the local-density-functional width, 21.5±0.2 eV2. This difference quantifies effects of creating an excited hole state (with associated many-body effects) in a band measurement vs studying ground-state properties treated by local-density-functional calculations. copyright 1997 The American Physical Society

  9. Biology Reflective Assessment Curriculum

    Bayley, Cheryl Ann

    Often students and educators view assessments as an obligation and finality for a unit. In the current climate of high-stakes testing and accountability, the balance of time, resources and emphasis on students' scores related to assessment have been slanted considerably toward the summative side. This tension between assessment for accountability and assessment to inform teaching strains instruction and educators' ability to use that information to design learning opportunities that help students develop deeper conceptual understanding. A substantive body of research indicates that formative and reflective assessment can significantly improve student learning. Biology Reflective Assessment Curriculum (BRAC) examines support provided for high school science students through assessment practices. This investigation incorporates the usage of reflective assessments as a guiding practice for differentiated instruction and student choice. Reflective assessment is a metacognitive strategy that promotes self-monitoring and evaluation. The goals of the curriculum are to promote self-efficacy and conceptual understanding in students learning biology through developing their metacognitive awareness. BRAC was implemented in a high school biology classroom. Data from assessments, metacognitive surveys, self-efficacy surveys, reflective journals, student work, a culminating task and field notes were used to evaluate the effectiveness of the curriculum. The results suggest that students who develop their metacognitive skills developed a deeper conceptual understanding and improved feelings of self-efficacy when they were engaged in a reflective assessment unit embedded with student choice. BRAC is a tool for teachers to use assessments to assist students in becoming metacognitive and to guide student choice in learning opportunities.

  10. Accurate Weather Forecasting for Radio Astronomy

    Maddalena, Ronald J.

    2010-01-01

    The NRAO Green Bank Telescope routinely observes at wavelengths from 3 mm to 1 m. As with all mm-wave telescopes, observing conditions depend upon the variable atmospheric water content. The site provides over 100 days/yr when opacities are low enough for good observing at 3 mm, but winds on the open-air structure reduce the time suitable for 3-mm observing where pointing is critical. Thus, to maximum productivity the observing wavelength needs to match weather conditions. For 6 years the telescope has used a dynamic scheduling system (recently upgraded; www.gb.nrao.edu/DSS) that requires accurate multi-day forecasts for winds and opacities. Since opacity forecasts are not provided by the National Weather Services (NWS), I have developed an automated system that takes available forecasts, derives forecasted opacities, and deploys the results on the web in user-friendly graphical overviews (www.gb.nrao.edu/ rmaddale/Weather). The system relies on the "North American Mesoscale" models, which are updated by the NWS every 6 hrs, have a 12 km horizontal resolution, 1 hr temporal resolution, run to 84 hrs, and have 60 vertical layers that extend to 20 km. Each forecast consists of a time series of ground conditions, cloud coverage, etc, and, most importantly, temperature, pressure, humidity as a function of height. I use the Liebe's MWP model (Radio Science, 20, 1069, 1985) to determine the absorption in each layer for each hour for 30 observing wavelengths. Radiative transfer provides, for each hour and wavelength, the total opacity and the radio brightness of the atmosphere, which contributes substantially at some wavelengths to Tsys and the observational noise. Comparisons of measured and forecasted Tsys at 22.2 and 44 GHz imply that the forecasted opacities are good to about 0.01 Nepers, which is sufficient for forecasting and accurate calibration. Reliability is high out to 2 days and degrades slowly for longer-range forecasts.

  11. Focused crossed Andreev reflection

    Haugen, H.; Brataas, A.; Waintal, X.; Bauer, G. E. W.

    2011-03-01

    We consider non-local transport mediated by Andreev reflection in a two-dimensional electron gas (2DEG) connected to one superconducting and two normal metal terminals. A robust scheme is presented for observing crossed Andreev reflection (CAR) between the normal metal terminals based on electron focusing by weak perpendicular magnetic fields. At slightly elevated temperatures the CAR signature can be easily distinguished from a background of quantum interference fluctuations. The CAR-induced entanglement between electrons can be switched on and off over large distances by the magnetic field.

  12. Reflection from black holes

    Kuchiev, M Yu

    2003-01-01

    Black holes are presumed to have an ideal ability to absorb and keep matter. Whatever comes close to the event horizon, a boundary separating the inside region of a black hole from the outside world, inevitably goes in and remains inside forever. This work shows, however, that quantum corrections make possible a surprising process, reflection: a particle can bounce back from the event horizon. For low energy particles this process is efficient, black holes behave not as holes, but as mirrors, which changes our perception of their physical nature. Possible ways for observations of the reflection and its relation to the Hawking radiation process are outlined.

  13. Postscript: Delving into Reflection

    Susan Noffke

    2005-09-01

    Full Text Available Although, the authors presented an earlier version of the paper, "The Dimensions of Reflection: A Conceptual and Contextual Analysis", at the Annual Meeting of the American Educational Research Association, New Orleans, April, 1988, they did not have a chance to publish the paper till today. This postscript is about why the paper stayed as an “unpublished” conference paper for so long. Editors believe that the authors’ reflection on their academic journey with the paper in the postscript could be seen as an outstanding practical exemplar, a moral-political narrative of how to shape and create well-formed academic lives and identities.

  14. Cardiac electrical stunning is a common feature of cardiac arrhythmias.

    Li, Guangping; Liu, Tong; Liu, Enzhao

    2006-01-01

    There are many published papers focused on the topic of atrial electrical remodeling, which defined as the shortening and dispersion of effective refractory period (ERP) in patients with paroxysmal or persistent tachyarrhythmias or in animals with long-term rapid atrial pacing. Heart failure could produce the electrical remodeling of sinus node, manifesting the prolongation of corrected sinus node recovery time and sinus cycle length. It might be attributed to decreased hyperpolarization-activated cyclic nucleotide expression of sinus node. Rapid atrial pacing for only 10-15 min, simulating transient atrial tachyarrhythmias, alters sinus node function in human. Termination of atrial flutter by ablation induces reversible changes in sinus node function. After atrial fibrillation (AF) ablation, there was a significant improvement of sinus node function, with an increase in the mean heart rate, maximal heart rate and heart rate range significantly. Reverse electrical remodeling of the ERP occurs at different rates in different regions of the atrium. Previous experiments showed that electrical remodeling of atrial myocardium could be induced by autonomic nervous transmitters and suggested that autonomic nerve activity was an important factor to promote AF episodes. We postulated that electrical remodeling and reverse electrical remodeling are common features of the heart, including atrium, ventricle, sinus node, and conductive system. Inappropriate very rapid or slow electrical depolarization may cause electrical remodeling of the heart, but appropriate rates of electrical depolarization and cessation of rapid stimulation may contribute to the reverse electrical remodeling. So, we forward that a concept defined as cardiac electrical stunning, including electrical remodeling and reverse electrical remodeling, should be a common characteristic and mechanism of cardiac arrhythmias. PMID:16759818

  15. Integral representation of Skorokhod reflection

    Anantharam, Venkat; Konstantopoulos, Takis

    2010-01-01

    We show that a certain integral representation of the one-sided Skorokhod reflection of a continuous bounded variation function characterizes the reflection in that it possesses a unique maximal solution which solves the Skorokhod reflection problem.

  16. Long Wave Reflection and Transmission over A Sloping Step

    Hsien-Kuo CHANG; Jin-Cheng LIOU

    2004-01-01

    This investigation examines long wave reflection and transmission induced by a sloping step. Bellman and Kalaba's(1959) invariant imbedding is introduced to find wave reflection. An alternative method matching both the surface elevation and its surface slope of each region at the junction is applied to the determination of wave reflection and transmission.The proposed methods are compared with the accurate numerical results of Porter and Porter (2000) and those of Mei(1983) for a vertical step. The wave reflection obtained for a mildly sloping step differs significantly from the result of Mei. The wave reflection is found to fluctuate owing to wave trapping for the mild sloping step. The height and the face slope of the step are important for determining wave reflection and transmission coefficients.

  17. Simulation studies and the need for field reflectance studies

    Duggin, M. J.

    1983-01-01

    There is a need to calibrate satellite data obtained at large polar (i.e., off-nadir) view angles for effects caused by scanner geometry and by the atmosphere. If such effects are not corrected for, then recorded radiance data will contain systematic and random errors which will make accurate target identification and quantification difficult. Adequate calibration of digital radiance data requires both an inductive analysis of digital satellite images and a deductive analysis based upon a priori simulation studies. The inputs to a simulation model (ground reflectance, atmospheric transmission and bandscatter) and their variability are dependent upon (for example) sun-target-sensor geometry. There is a major need to make accurate ground reflectance measurements to provide calibration information on the anisotropy of ground reflectance. There is also a need to assess atmospheric transmission and backscatter from the image itself. A potential simple, inexpensive method for making ground reflectance measurements in the above context is discussed.

  18. Reflection in learning at work

    Pedersen, Steen Høyrup

    2006-01-01

    Three domains and approaches of learning - adult learning, problem-solving and cirtical reflection theory are used as different lenses through which the question: what is reflection and how is reflection related to learning, - are interpreted.......Three domains and approaches of learning - adult learning, problem-solving and cirtical reflection theory are used as different lenses through which the question: what is reflection and how is reflection related to learning, - are interpreted....

  19. Runtime software architecture based on reflective middleware

    HUANG Gang; MEI Hong; YANG Fuqing

    2004-01-01

    There exists a consensus that software architecture (SA) plays a central role in software development and also plays an important role in the lifecycle phases after software delivery. Particularly, SA can be used to reduce the great difficulty and cost of software maintenance and evolution. In this paper, runtime software architecture (RSA) based on reflective middleware is proposed to support architecture-based software maintenance and evolution. In this approach, the actual states and behaviors of the runtime system can be observed and manipulated in a consistent and understandable way through its architectural view. Being an accurate, up-to-date, semantic and operable view of SA, RSA looks components and connectors as "white-box" entities to accurately and thoroughly describe the runtime system, extends traditional architecture description languages to formally describe itself and naturally inherit plentiful semantics in traditional views of SA, and utilizes reflective middleware to observe and manipulate the runtime system. In order to demonstrate the feasibility of this approach, a reflective J2EE application server, called PKUAS, is implemented to observe and manipulate the components, connectors and constraints in the runtime system. Finally, the performance evaluation proves that making RSA explicit and operable at runtime has little effect on the runtime system.

  20. SWIR calibration of Spectralon reflectance factor

    Georgiev, Georgi T.; Butler, James J.; Cooksey, Catherine; Ding, Leibo; Thome, Kurtis J.

    2011-11-01

    Satellite instruments operating in the reflective solar wavelength region require accurate and precise determination of the Bidirectional Reflectance Factor (BRF) of laboratory-based diffusers used in their pre-flight and on-orbit radiometric calibrations. BRF measurements are required throughout the reflected-solar spectrum from the ultraviolet through the shortwave infrared. Spectralon diffusers are commonly used as a reflectance standard for bidirectional and hemispherical geometries. The Diffuser Calibration Laboratory (DCaL) at NASA's Goddard Space Flight Center is a secondary calibration facility with reflectance measurements traceable to those made by the Spectral Tri-function Automated Reference Reflectometer (STARR) facility at the National Institute of Standards and Technology (NIST). For more than two decades, the DCaL has provided numerous NASA projects with BRF data in the ultraviolet (UV), visible (VIS) and the Near InfraRed (NIR) spectral regions. Presented in this paper are measurements of BRF from 1475 nm to 1625 nm obtained using an indium gallium arsenide detector and a tunable coherent light source. The sample was a 50.8 mm (2 in) diameter, 99% white Spectralon target. The BRF results are discussed and compared to empirically generated data from a model based on NIST certified values of 6°directional-hemispherical spectral reflectance factors from 900 nm to 2500 nm. Employing a new NIST capability for measuring bidirectional reflectance using a cooled, extended InGaAs detector, BRF calibration measurements of the same sample were also made using NIST's STARR from 1475 nm to 1625 nm at an incident angle of 0° and at viewing angle of 45°. The total combined uncertainty for BRF in this ShortWave Infrared (SWIR) range is less than 1%. This measurement capability will evolve into a BRF calibration service in SWIR region in support of NASA remote sensing missions.

  1. Punctum: Reflections on Photography

    Fusco, Maria

    2014-01-01

    Group show for which I was invited to contribute one photograph to the exhibition Punctum. Consisting of fifty photographs and artworks chosen by artists, curators and writers, curated by Séamus Kealy, Punctum takes its cue from the term “punctum” coined by Roland Barthes in his final book Camera Lucida: Reflections on Photography.

  2. The Reflective Methodologists

    Kjær, Bjørg

    2013-01-01

    in which the practical sense and tacit knowledge are related to questions of power and social actors’ strategies for positioning themselves within a social space. This demands a particular focus on the historical effect of the concept of ‘the reflective practitioner’ as a symbolic marker of identity...

  3. Reflection by Porro Prisms

    Greenslade, Thomas B.

    2010-04-01

    Students all know that reflection from a plane mirror produces an image that is reversed right to left and so cannot be read by anyone but Leonardo da Vinci, who kept his notes in mirror writing. A useful counter-example is the Porro prism, which produces an image that is not reversed.

  4. Reflecting on Data

    Kraus, Rudolf V.

    2014-01-01

    This article describes a two-day optics laboratory activity that investigates the scientific phenomenon of reflection, which students are generally familiar with but usually have not studied in depth. This investigation can be used on its own or as part of a larger unit on optics. This lesson encourages students to think critically and…

  5. Changes Brought by Reflection

    2004-01-01

    Feng: A number of changes have taken place in Europe after reflection, such as specific anti-terrorist measures, progress in the construction of integration, changes in the structure of political forces and adjustments in the EU foreign policy. Would you make some comments first, Dr. Sun?

  6. Lights, Camera, Reflection!

    Mourlam, Daniel

    2013-01-01

    There are many ways to critique teaching, but few are more effective than video. Personal reflection through the use of video allows one to see what really happens in the classrooms--good and bad--and provides a visual path forward for improvement, whether it be in one's teaching, work with a particular student, or learning environment. This…

  7. Wave Reflection Model Tests

    Burcharth, H. F.; Larsen, Brian Juul

    The investigation concerns the design of a new internal breakwater in the main port of Ibiza. The objective of the model tests was in the first hand to optimize the cross section to make the wave reflection low enough to ensure that unacceptable wave agitation will not occur in the port. Secondly...

  8. Progress in use of brain natriuretic peptide in congenital heart disease and perioperative pediatric cardiac operation%脑钠肽在小儿先天性心脏病及围手术期的应用进展

    肖书娜

    2013-01-01

    脑钠肽是一种神经内分泌激素,它与先天性心脏病患儿心功能不全和肺动脉高压程度呈正相关,已成为评估先天性心脏病患儿心功能不全程度、反映先天性心脏病患儿术前术后心功能状态的简便、准确的生物化学指标.它对先天性心脏病心脏手术预后有预测作用,对围手术期治疗有指导意义,能减少术后并发症和病死率,成为迅速、即时床边检查的辅助手段.该文就其与先天性心脏病的相关性和在先天性心脏病围手术期应用进展作一概述.%Brain natriuretic peptide (BNP) is a neuroendocrine hormone,which has a positive correlation with degree of cardiac dysfunction and pulmonary arterial hypertension of children with congenital heart disease (CHD).BNP has been shown to be a simple,accurate and useful biochemical indicator in assessing cardiac dysfunction degree and reflecting perioperative cardiac function state of children with CHD.It has prognostic value in congenital heart surgery and can guide the perioperative treatment and reduce the postoperative complications and mortality.It is a quick,instant bedside inspection supplementary means.This article describes the relevance between BNP and CHD and the application progress of BNP in pefioperative of CHD.

  9. Evaluation of spectral reflectance of seven Iranian rice varieties canopies

    Darvishsefat, A A; Abbasi, M.; Schaepman, Michael E.

    2011-01-01

    Rice cultivated areas and yield information is indispensable for sustainable management and economic policy making for this strategic food crop. Introduction of high spectral and special resolution satellite data has enabled production of such information in a timely and accurate manner. Knowledge of the spectral reflectance of various land covers is a prerequisite for their identification and study. Evaluation of the spectral reflectance of plants using field spectroradiometry provides the p...

  10. Computational 3D and reflectivity imaging with high photon efficiency

    Shin, Dongeek; Kirmani, Ahmed; Shapiro, Jeffrey H.; Goyal, Vivek K

    2014-01-01

    Capturing depth and reflectivity images at low light levels from active illumination of a scene has wide-ranging applications. Conventionally, even with single-photon detectors, hundreds of photon detections are needed at each pixel to mitigate Poisson noise. We introduce a robust method for estimating depth and reflectivity using on the order of 1 detected photon per pixel averaged over the scene. Our computational imager combines physically accurate single-photon counting statistics with ex...

  11. The Effects That Cardiac Motion has on Coronary Hemodynamics and Catheter Trackability Forces for the Treatment of Coronary Artery Disease: An In Vitro Assessment.

    Morris, Liam; Fahy, Paul; Stefanov, Florian; Finn, Ronan

    2015-12-01

    The coronary arterial tree experiences large displacements due to the contraction and expansion of the cardiac muscle and may influence coronary haemodynamics and stent placement. The accurate measurement of catheter trackability forces within physiological relevant test systems is required for optimum catheter design. The effects of cardiac motion on coronary flowrates, pressure drops, and stent delivery has not been previously experimentally assessed. A cardiac simulator was designed and manufactured which replicates physiological coronary flowrates and cardiac motion within a patient-specific geometry. A motorized delivery system delivered a commercially available coronary stent system and monitored the trackability forces along three phantom patient-specific thin walled compliant coronary vessels supported by a dynamic cardiac phantom model. Pressure drop variation is more sensitive to cardiac motion than outlet flowrates. Maximum pressure drops varied from 7 to 49 mmHg for a stenosis % area reduction of 56 to 90%. There was a strong positive linear correlation of cumulative trackability force with the cumulative curvature. The maximum trackability forces and curvature ranged from 0.24 to 0.87 N and 0.06 to 0.22 mm(-1) respectively for all three vessels. There were maximum and average percentage differences in trackability forces of (23-49%) and (1.9-5.2%) respectively when comparing a static pressure case with the inclusion of pulsatile flow and cardiac motion. Cardiac motion with pulsatile flow significantly altered (p value local percentage variations and pressure drop measurements. PMID:26577477

  12. Psychosocial aspects in cardiac rehabilitation

    Pogosova, N. V.; Saner, H.; Pedersen, S. S.;

    2015-01-01

    A large body of empirical research shows that psychosocial risk factors (PSRFs) such as low socio-economic status, social isolation, stress, type-D personality, depression and anxiety increase the risk of incident coronary heart disease (CHD) and also contribute to poorer health- related quality...... of life (HRQoL) and prognosis in patients with establishedCHD. PSRFs may also act as barriers to lifestyle changes and treatment adherence and may moderate the effects of cardiac rehabilitation (CR). Furthermore, there appears to be a bidirectional interaction between PSRFs and the cardiovascular system....... Stress, anxiety and depression affect the cardiovascular system through immune, neuroendocrine and behavioural pathways. In turn, CHD and its associated treatments may lead to distress in patients, including anxiety and depression. In clinical practice, PSRFs can be assessed with single-item screening...

  13. Psychosocial aspects in cardiac rehabilitation

    Pogosova, Nana; Saner, Hugo; Pedersen, Susanne S.;

    2015-01-01

    A large body of empirical research shows that psychosocial risk factors (PSRFs) such as low socio-economic status, social isolation, stress, type-D personality, depression and anxiety increase the risk of incident coronary heart disease (CHD) and also contribute to poorer health-related quality...... of life (HRQoL) and prognosis in patients with established CHD. PSRFs may also act as barriers to lifestyle changes and treatment adherence and may moderate the effects of cardiac rehabilitation (CR). Furthermore, there appears to be a bidirectional interaction between PSRFs and the cardiovascular system....... Stress, anxiety and depression affect the cardiovascular system through immune, neuroendocrine and behavioural pathways. In turn, CHD and its associated treatments may lead to distress in patients, including anxiety and depression. In clinical practice, PSRFs can be assessed with single-item screening...

  14. Cardiac Rehabilitation: Improving Function and Reducing Risk.

    Servey, Jessica T; Stephens, Mark

    2016-07-01

    Cardiac rehabilitation is a comprehensive multidisciplinary program individually tailored to the needs of patients with cardiovascular disease. The overall goals focus on improving daily function and reducing cardiovascular risk factors. Cardiac rehabilitation includes interventions aimed at lowering blood pressure and improving lipid and diabetes mellitus control, with tobacco cessation, behavioral counseling, and graded physical activity. The physical activity component typically involves 36 sessions over 12 weeks, during which patients participate in supervised exercise under cardiac monitoring. There are also intensive programs that include up to 72 sessions lasting up to 18 weeks, although these programs are not widely available. Additional components of cardiac rehabilitation include counseling on nutrition, screening for and managing depression, and assuring up-to-date immunizations. Cardiac rehabilitation is covered by Medicare and recommended for patients following myocardial infarction, bypass surgery, and stent placement, and for patients with heart failure, stable angina, and several other conditions. Despite proven benefits in mortality rates, depression, functional capacity, and medication adherence, rates of referral for cardiac rehabilitation are suboptimal. Groups less likely to be referred are older adults, women, patients who do not speak English, and persons living in areas where cardiac rehabilitation is not locally available. Additionally, primary care physicians refer patients less often than cardiologists and cardiothoracic surgeons. PMID:27386722

  15. A mechanical simulator of cardiac wall kinematics.

    Cutrì, Elena; Bagnoli, Paola; Marcelli, Emanuela; Biondi, Federico; Cercenelli, Laura; Costantino, Maria Laura; Plicchi, Gianni; Fumero, Roberto

    2010-01-01

    Aim of this study is to develop a mechanical simulator (MS) reproducing cardiac wall kinematics [i.e., radial (R), longitudinal (L) and rotational (RT) motions] to test piezoelectric gyroscopic sensors (GS) that are able to measure cardiac torsion that has proved to be a sensitive index of cardiac performance. The MS consists of three brushless motors controlled by a dedicated software either separately or simultaneously reproducing the three main cardiac wall movements (R, L, RT) obtained by implementing different physiologic or pathologic velocity profiles derived from in vivo data. GS accuracy (max % error) was experimentally tested by connecting it to the MS driven in velocity in different working conditions [i.e., cardiac period (515-1030 ms), RT angle (4-16 degrees), GS axis inclination (0-90 degrees) with respect to the cardiac rotation axis]. The MS reproduced the tested velocity profiles well. The GS showed high accuracy in measuring both physiologic and pathologic RT velocity profiles, whereas they proved insensitive to R and L motions. GS axis inclination influenced measurements; however, it was possible to correct this taking the inclination angle cosine into account. The MS proved to be a useful tool to study cardiac wall kinematics and test GS reliability with a view to in vivo application. PMID:20404720

  16. MRS: a noninvasive window into cardiac metabolism.

    van Ewijk, Petronella A; Schrauwen-Hinderling, Vera B; Bekkers, Sebastiaan C A M; Glatz, Jan F C; Wildberger, Joachim E; Kooi, M Eline

    2015-07-01

    A well-functioning heart requires a constant supply of a balanced mixture of nutrients to be used for the production of adequate amounts of adenosine triphosphate, which is the main energy source for most cellular functions. Defects in cardiac energy metabolism are linked to several myocardial disorders. MRS can be used to study in vivo changes in cardiac metabolism noninvasively. MR techniques allow repeated measurements, so that disease progression and the response to treatment or to a lifestyle intervention can be monitored. It has also been shown that MRS can predict clinical heart failure and death. This article focuses on in vivo MRS to assess cardiac metabolism in humans and experimental animals, as experimental animals are often used to investigate the mechanisms underlying the development of metabolic diseases. Various MR techniques, such as cardiac (31) P-MRS, (1) H-MRS, hyperpolarized (13) C-MRS and Dixon MRI, are described. A short overview of current and emerging applications is given. Cardiac MRS is a promising technique for the investigation of the relationship between cardiac metabolism and cardiac disease. However, further optimization of scan time and signal-to-noise ratio is required before broad clinical application. In this respect, the ongoing development of advanced shimming algorithms, radiofrequency pulses, pulse sequences, (multichannel) detection coils, the use of hyperpolarized nuclei and scanning at higher magnetic field strengths offer future perspective for clinical applications of MRS. PMID:26010681

  17. Sudden cardiac arrest following ventricular fibrillation attributed to anabolic steroid use in an adolescent.

    Lichtenfeld, Jana; Deal, Barbara J; Crawford, Susan

    2016-06-01

    Anabolic androgenic steroids are synthetic derivatives of testosterone that promote the growth of skeletal muscles and have many recognised cardiovascular effects. We report the clinical presentation and pathological findings of an adolescent male whose sudden cardiac arrest following ventricular fibrillation was attributed to anabolic androgenic steroid use. The age of our patient reflects the usage of anabolic androgenic steroids among younger athletes and highlights the need for increased awareness among practitioners. PMID:26980272

  18. Evolutionary origin of cardiac malformations.

    Taussig, H B

    1988-10-01

    The author has proposed in previous publications that isolated cardiac malformations have an evolutionary origin. This is partly supported by the fact that isolated cardiac malformations found in humans occur also in other placental mammals as well as in birds. External gross examination of the heart in just over 5,000 birds was carried out during a 3 year period. Anomalies included one instance of duplicate hearts, two specimens in which no heart could be identified and in a fourth, a yellow-rumped warbler, the heart lay in the neck outside of the thoracic cavity. Published reports of similar occurrences of an ectopically placed heart concern birds, cattle and humans. The fact that various species of both placental mammals and birds show evidence of heritability for heart defects, and that these species cannot interbreed, combined with the fact that birds and mammals have many similar malformations, points to either a common external causative factor or a common origin. Genes that code the malformed heart must be transmitted with that part of the genetic makeup common to all birds and mammals. Malformations caused by teratogens produce widespread organ injury to a potentially normal embryo whereas the evolutionary malformation is an organ-specific anomaly in an otherwise normal mammal or bird and occurs in widely separated species. The implications of this theory are important for parents of children with an isolated congenital heart defect who may have ingested one or another drug or chemical or have been exposed to toxins or infectious agents before or after conception of the affected offspring. PMID:3047192

  19. Measuring Practicum Student Teachers' Reflectivity: The Reflective Pedagogical Thinking Scale

    Seng, Toh Wah

    2004-01-01

    The purpose of the original study was to investigate practicum student teachers' reflectivity. This paper describes the use of a revised version of the Reflective Pedagogical Thinking Scale (Sparks-Langer, et al., 1990) to measure reflectivity. The original scale was used by the developers to assess reflectivity through a structured interview. The…

  20. Being a reflective teacher——reflection on group management

    Pan; Lehui

    2015-01-01

    <正>Introduction According to Pollard and Triggs(1997),reflective teaching is a process through which the capacity to make such professional judgments can be developed and maintained.Then what is a reflective teacher?Reflective teacher is someone who reflects systematically on her practice in a constant attempt to improve

  1. The Learning Curve for a Fetal Cardiac Intervention Team

    Stephen P. Emery

    2010-01-01

    Full Text Available Objectives. Multiple technical difficulties are encountered when a multidisciplinary team of subspecialists begins a minimally-invasive fetal cardiac interventional program. We describe the learning curve. Study Design. Ten pregnant sheep underwent ultrasound-guided balloon valvuloplasty of the aortic valve. Team members and their roles remained constant through the trial. The time between needle insertion and entrance of the left ventricle at the aortic root was recorded. F-test was used to assess significance (P≤.05. Results. The time required to accurately position the needle tip at the aortic root decreased significantly over the course of the trial, from 12 minutes with the first attempt to one minute with the last (P=.003. Conclusion. A significant learning curve is encountered when a multidisciplinary team begins a minimally-invasive fetal cardiac intervention program. However, technical proficiency can be achieved with practice. Institutions interested in developing such a program should consider practice in an animal model before proceeding to the human fetus.

  2. The floating cardiac fat pad-sign of occult pneumothorax.

    Kaufman, Claire; Bokhari, S A Jamal

    2016-08-01

    Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph. PMID:27250975

  3. Robust inter-beat interval estimation in cardiac vibration signals

    Reliable and accurate estimation of instantaneous frequencies of physiological rhythms, such as heart rate, is critical for many healthcare applications. Robust estimation is especially challenging when novel unobtrusive sensors are used for continuous health monitoring in uncontrolled environments, because these sensors can create significant amounts of potentially unreliable data. We propose a new flexible algorithm for the robust estimation of local (beat-to-beat) intervals from cardiac vibration signals, specifically ballistocardiograms (BCGs), recorded by an unobtrusive bed-mounted sensor. This sensor allows the measurement of motions of the body which are caused by cardiac activity. Our method requires neither a training phase nor any prior knowledge about the morphology of the heart beats in the analyzed waveforms. Instead, three short-time estimators are combined using a Bayesian approach to continuously estimate the inter-beat intervals. We have validated our method on over-night BCG recordings from 33 subjects (8 normal, 25 insomniacs). On this dataset, containing approximately one million heart beats, our method achieved a mean beat-to-beat interval error of 0.78% with a coverage of 72.69%. (paper)

  4. Multimodal Registration of gated cardiac PET, CT and MR sequences

    The research described in this manuscript deals with the multimodal registration of cardiac images from Magnetic Resonance Imaging (MRI), Position Emission Tomography (PET) and Computerized Tomography (CT). All these modalities are gated to the Electrocardiogram (ECG) and provide information to evaluate cardiac function, and to diagnose and to follow-up cardiovascular pathologies. PET imaging allows the evaluation of ventricular function and MRI is a gold standard for the study of the left ventricular function. The goal of our registration process is to merge functional (from PET) and anatomical images (from CT and MRI). Our process is adapted to the modalities used and is divided in two steps: (i) a global rigid 3-dimensional model-based ICP (Iterative Closest Point) registration between CT and MR data and (ii) an iconic 2-dimensional registration based on Free Form Deformations and Mutual Information. This last step presents an original contribution by using a composite image of CT (which presents epicardic contours) and PET (where endocardic contours are partially visible) data to make mutual information more accurate in representing the similarity with the MR data. To speed up the whole process, we also present a transformation initialization scheme using displacement field obtained form MR data only. The obtained results have been evaluated by experts. (author)

  5. Subject-specific models for image-guided cardiac surgery

    Three-dimensional visualization for planning and guidance is still not routinely available for minimally invasive cardiac surgery (MICS). This can be addressed by providing the surgeon with subject-specific geometric models derived from 3D preoperative images for planning of port locations or to rehearse the procedure. For guidance purposes, these models can also be registered to the subject using intraoperative images. In this paper, we present a method for extracting subject-specific heart geometry from preoperative MR images. The main obstacle we face is the low quality of clinical data in terms of resolution, signal-to-noise ratio, and presence of artefacts. Instead of using these images directly, we approach the problem in three steps: (1) generate a high quality template model, (2) register the template with the preoperative data, and (3) animate the result over the cardiac cycle. Validation of this approach showed that dynamic subject-specific models can be generated with a mean error of 3.6 ± 1.1 mm from low resolution target images (6 mm slices). Thus, the models are sufficiently accurate for MICS training and procedure planning. In terms of guidance, we also demonstrate how the resulting models may be adapted to the operating room using intraoperative ultrasound imaging

  6. Two cases of chronic radiodermatitis caused by cardiac catheterization

    Coronary angiography (CAG) and percutaneous transluminal coronary angioplasty (PTCA) associated with fluoroscopy and cineradiography deliver higher radiation doses than any other conventional methods and, as a result, expose patients to ionizing radiation. We herein report two cases of radiodermatitis caused by cardiac catheterization whose irradiation dose could be retrospectively calculated. One sixty-year-old female and one sixty eight-year-old female who had suffered from myocardial infarction and angina pectoris, respectively, developed erythematous plaques on the right submammary area and the lesions were initially diagnosed to be fixed drug eruptions. The lesions of submammary area gradually showed the findings of poikiloderma and finally demonstrated ulceration, however, we could not make an accurate diagnosis at that time, due to our lack of knowledge about these radiologic examinations. The cumulative irradiation dose of these cases was calculated to be 58.5 Gy and 45.5 Gy, respectively, and both cases were finally diagnosed to have chronic radiodermatitis as a result of cardiac catheterization. (author)

  7. Radiation exposure to the child during cardiac catheterization

    Few data are available regarding radiation exposure to children during cardiac catheterization. Using lithium fluoride thermoluminescent dosimeters, radiation exposure was measured during precatheterization chest roentgenography, fluoroscopy (hemodynamic assessment phase of catheterization) and cineangiography in 30 infants and children, ages 3 days to 21 years. Dosimeters were placed over the eyes, thyroid, anterior chest, posterior chest, anterior abdomen, posterior abdomen and gonads. Average absorbed chest doses were 24.5 mR during chest roentgenography, 5810 mR during catheterization fluoroscopy and 1592 mR during cineangiography. During the complete catheterization, average doses were 26 mR to the eyes, 431 mR to the thyroid area, 150 mR to the abdomen and 11 mR to the gonads. Radiation exposure during pediatric cardiac catheterization is low to the eyes and gonads but high to the chest and thyroid area. To decrease radiation dosage we suggest (1) low pulse-rate fluoroscopy; (2) substitution of contrast echocardiography for cineangiography; (3) large-plate abdominal/gonadal shielding; (4) a selective shield for thyroid area; (5) a very small field during catheter manipulation. Minimum radiation consistent with accurate diagnosis is optimal; however, erroneous or incomplete diagnosis is more dangerous than radiation-related hazards

  8. Fast and Provably Accurate Bilateral Filtering.

    Chaudhury, Kunal N; Dabhade, Swapnil D

    2016-06-01

    The bilateral filter is a non-linear filter that uses a range filter along with a spatial filter to perform edge-preserving smoothing of images. A direct computation of the bilateral filter requires O(S) operations per pixel, where S is the size of the support of the spatial filter. In this paper, we present a fast and provably accurate algorithm for approximating the bilateral filter when the range kernel is Gaussian. In particular, for box and Gaussian spatial filters, the proposed algorithm can cut down the complexity to O(1) per pixel for any arbitrary S . The algorithm has a simple implementation involving N+1 spatial filterings, where N is the approximation order. We give a detailed analysis of the filtering accuracy that can be achieved by the proposed approximation in relation to the target bilateral filter. This allows us to estimate the order N required to obtain a given accuracy. We also present comprehensive numerical results to demonstrate that the proposed algorithm is competitive with the state-of-the-art methods in terms of speed and accuracy. PMID:27093722

  9. Accurate adiabatic correction in the hydrogen molecule

    Pachucki, Krzysztof, E-mail: krp@fuw.edu.pl [Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw (Poland); Komasa, Jacek, E-mail: komasa@man.poznan.pl [Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznań (Poland)

    2014-12-14

    A new formalism for the accurate treatment of adiabatic effects in the hydrogen molecule is presented, in which the electronic wave function is expanded in the James-Coolidge basis functions. Systematic increase in the size of the basis set permits estimation of the accuracy. Numerical results for the adiabatic correction to the Born-Oppenheimer interaction energy reveal a relative precision of 10{sup −12} at an arbitrary internuclear distance. Such calculations have been performed for 88 internuclear distances in the range of 0 < R ⩽ 12 bohrs to construct the adiabatic correction potential and to solve the nuclear Schrödinger equation. Finally, the adiabatic correction to the dissociation energies of all rovibrational levels in H{sub 2}, HD, HT, D{sub 2}, DT, and T{sub 2} has been determined. For the ground state of H{sub 2} the estimated precision is 3 × 10{sup −7} cm{sup −1}, which is almost three orders of magnitude higher than that of the best previous result. The achieved accuracy removes the adiabatic contribution from the overall error budget of the present day theoretical predictions for the rovibrational levels.

  10. Accurate fission data for nuclear safety

    Solders, A; Jokinen, A; Kolhinen, V S; Lantz, M; Mattera, A; Penttila, H; Pomp, S; Rakopoulos, V; Rinta-Antila, S

    2013-01-01

    The Accurate fission data for nuclear safety (AlFONS) project aims at high precision measurements of fission yields, using the renewed IGISOL mass separator facility in combination with a new high current light ion cyclotron at the University of Jyvaskyla. The 30 MeV proton beam will be used to create fast and thermal neutron spectra for the study of neutron induced fission yields. Thanks to a series of mass separating elements, culminating with the JYFLTRAP Penning trap, it is possible to achieve a mass resolving power in the order of a few hundred thousands. In this paper we present the experimental setup and the design of a neutron converter target for IGISOL. The goal is to have a flexible design. For studies of exotic nuclei far from stability a high neutron flux (10^12 neutrons/s) at energies 1 - 30 MeV is desired while for reactor applications neutron spectra that resembles those of thermal and fast nuclear reactors are preferred. It is also desirable to be able to produce (semi-)monoenergetic neutrons...

  11. Cardiac imaging: Current and emerging applications

    Jankharia B

    2010-01-01

    Full Text Available Cardiac magnetic resonance imaging (MRI and computed tomography (CT scan have made big inroads as modalities used for evaluation of various pathologies of the heart. Cardiac MRI is typically used for perfusion and viability studies as well as to study various cardiomyopathies, valvular diseases and the pericardium. It has been used in the evaluation of congenital heart diseases over the last two decades. Cardiac CT is used mainly for the evaluation of the coronary arteries, typically in the setting of "to rule out coronary artery disease".

  12. Cardiac Amyloidosis Presenting With Cardiogenic Shock.

    Afzal, Ashwad; Brener, Sorin J; Narula, Navneet; Worku, Berhane; Gulkarov, Iosif

    2016-01-01

    Cardiac amyloidosis is an infiltrative disorder of the myocardium. It is the result of one of 4 types of amyloidosis: primary systemic (immunoglobulin light chain), secondary, familial (hereditary), or senile. Cardiac amyloidosis ultimately causes congestive heart failure due to irreversible restrictive cardiomyopathy. Because of the rapid progression of the disease, early recognition and determination of underlying etiology are important for tailored therapy. Current interventions range from conservative heart failure management to autologous stem cell and heart transplantation. We present a case of cardiac amyloidosis accompanying undiagnosed multiple myeloma to illustrate the rapid progression of the disease and the complexities of diagnosing and treating this disorder. PMID:26177555

  13. Investigations concerning the application of the cross-correlation method in cardiac output measurements

    Gawlikowski Maciej

    2012-05-01

    Full Text Available Abstract Background In spite of numerous non-invasive examinations the “gold clinical standard” of cardiac output measurements is the invasive pulmonary artery catheterization by means of the Swan-Ganz catheter and the application of the thermodilution method to estimate the blood flow. The results obtained by means of thermodilution are sensitive to many physical and biological disturbances. The unreliability of this method amounts to 20-45% and depends on the given variant of the method. Therefore some other method, more accurate and resistant to disturbances, was looked for. This paper presents a new approach to cardiac output measurements, based on cross-correlation signal analysis. The goal of investigations was to verify experimentally the application of the cross-correlation method of cardiac output measurements. Results In 99.2% of the examined cases the extreme of the cross-correlation function was easy to be estimated by numerical algorithms. In 0,8% of the remaining cases (with a plateau region adjacent to the maximum point numerical detection of the extreme was inaccurate. The typical unreliability of the investigated method amounted o 5.1% (9.8% in the worst case. Investigations performed on a physical model revealed that the unreliability of cardiac output measurements by means of the cross-correlation method is 3–5 times better than in the case of thermodilution. Conclusions The performed investigations and theoretical analysis have shown, that the cross-correlation method may be applied in cardiac output measurements. This kind of measurements seems to be more accurate and disturbance-resistant than clinically applied thermodilution.

  14. Minimizing artifacts resulting from respiratory and cardiac motion by optimization of the transmission scan in cardiac PET/CT

    The introduction of positron emission/computed tomography (PET/CT) systems coupled with multidetector CT arrays has greatly increased the amount of clinical information in myocardial perfusion studies. The CT acquisition serves the dual role of providing high spatial anatomical detail and attenuation correction for PET. However, the differences between the interaction of respiratory and cardiac cycles in the CT and PET acquisitions presents a challenge when using the CT to determine PET attenuation correction. Three CT attenuation correction protocols were tested for their ability to produce accurate emission images: gated, a step mode acquisition covering the diastolic heart phase; normal, a high-pitch helical CT; and slow, a low-pitch, low-temporal-resolution helical CT. The amount of cardiac tissue in the emission image that overlaid lung tissue in the transmission image was used as the measure of mismatch between acquisitions. Phantom studies simulating misalignment of the heart between the transmission and emission sequences were used to correlate the amount of mismatch with the artificial defect changes in the emission image. Consecutive patients were studied prospectively with either paired gated (diastolic phase, 120 kVp, 280 mA, 2.6 s) and slow CT (0.562:1 pitch, 120 kVp, Auto-mA, 16 s) or paired normal (0.938:1 pitch, 120 kVp, Auto-mA, 4.8 s) and slow CT protocols, prior to a Rb-82 perfusion study. To determine the amount of mismatch, the transmission and emission images were converted to binary representations of attenuating tissue and cardiac tissue and overlaid using their native registration. The number of cardiac tissue pixels from the emission image present in the CT lung field yielded the magnitude of misalignment represented in terms of volume, of where a small volume indicates better registration. Acquiring a slow CT improved registration between the transmission and emission acquisitions compared to the gated and normal CT protocols. The volume

  15. Cardiac carcinoid: tricuspid delayed hyperenhancement on cardiac 64-slice multidetector CT and magnetic resonance imaging.

    Martos, R

    2012-02-01

    INTRODUCTION: Carcinoid heart disease is a rare condition in adults. Its diagnosis can be easily missed in a patient presenting to a primary care setting. We revised the advantages of using coronary multidetector computed tomography (MDCT) and cardiac magnetic resonance imaging (MRI) in diagnosing this condition. MATERIALS AND METHODS: We studied a 65-year-old patient with carcinoid heart disease and right heart failure using transthoracic Doppler-echocardiogram, cardiac MDCT and MRI. Cardiac echocardiogram revealed marked thickening and retraction of the tricuspid leaflets with dilated right atrium and ventricle. Cardiac MDCT and MRI demonstrated fixation and retraction of the tricuspid leaflets with delayed contrast hyperenhancement of the tricuspid annulus. CONCLUSION: This case demonstrates fascinating imaging findings of cardiac carcinoid disease and highlights the increasing utility of contrast-enhanced MRI and cardiac MDCT in the diagnosis of this interesting condition.

  16. Efficient construction of robust artificial neural networks for accurate determination of superficial sample optical properties

    Chen, Yu-Wen; Tseng, Sheng-Hao

    2015-01-01

    In general, diffuse reflectance spectroscopy (DRS) systems work with photon diffusion models to determine the absorption coefficient μa and reduced scattering coefficient μs' of turbid samples. However, in some DRS measurement scenarios, such as using short source-detector separations to investigate superficial tissues with comparable μa and μs', photon diffusion models might be invalid or might not have analytical solutions. In this study, a systematic workflow of constructing a rapid, accur...

  17. Research on the cardiac MRI in the diagnosis and treatment of unstable angina%核磁共振在不稳定型心绞痛诊治中的应用价值

    李鹏; 亓燕

    2014-01-01

    Objective:To investigate the cardiac magnetic resonance technique in the diagnosis and treatment of unstable angina application value. Methods:The hospital diagnosed patients with unstable angina as research subjects, were given coronary angiography in patients (CAG) examination, ECG, echocardiography and cardiac MRI examination, recording the results and statistical analysis. Results:Cardiac MRI for>90%stenos is detected heart rate, and coronary angiography (CAG) showed no significant difference (x2=3.257, P>0.05), for0.05);cardiac MRI for cardiac function and cardiac structure determination is better than conventional echocardiography. Conclusion: Cardiac MRI technology to more accurately reflect changes in cardiac structure and function of the stenos is and effort ischemia detection rate with conventional inspection methods have better consistency.%目的:探讨核磁共振技术在不稳定心绞痛诊治中的应用价值。方法:选取经莱芜市人民医院确诊的不稳定心绞痛患者40例,分别给予冠状动脉造影(CAG)、心电图、超声心电图及心脏核磁共振检查,并对结果进行统计学分析。结果:核磁共振在心脏狭窄>90%的检出率高,与CAG间差异无统计学意义(x2=3.257,P>0.05),对<90%的狭窄检出率低,与CAG检查结果间差异有统计学意义(x2=17.267,x2=25.714;P<0.05);核磁共振对心脏狭窄程度高的患者的心肌缺血检出率高,与心电图检出率差异明显,有统计学意义(x2=4.65,P<0.05),但总检出率间差异不明显,无统计学意义(x2=0.251,P>0.05);核磁共振对于心功能及心脏结构的测定效果优于传统的超声心动图。结论:核磁共振技术能更准确的反应心脏结构和功能改变,对狭窄和心机缺血的检出率与传统检查方法有较好一致性。

  18. Differentiation of cardiac thrombus from cardiac tumor combining cardiac MRI and 18F-FDG-PET/CT Imaging.

    Rinuncini, Massimo; Zuin, Marco; Scaranello, Fiorenzo; Fejzo, Majlinda; Rampin, Lucia; Rubello, Domenico; Faggian, Giuseppe; Roncon, Loris

    2016-06-01

    Radiological differentiation of an unknown cardiac masse is often a challenging issue. 18F-FDG-PET/CT imaging was performed to evaluate a left ventricle mass visualized on transthoracic echocardiogram (TTE) and cardiac magnetic resonance (CMR) in a patient with an history of ischemic heart disease. The metabolically inert area on the PET/CT, corresponding to the relatively homogenous hypodensity in the LV, was thought to represent an old organized LV thrombus. Histopathological examination confirmed the imaging diagnosis. PMID:27038712

  19. Tetralogy of Fallot Cardiac Function Evaluation and Intelligent Diagnosis Based on Dual-Source Computed Tomography Cardiac Images.

    Cai, Ken; Rongqian, Yang; Li, Lihua; Xie, Zi; Ou, Shanxing; Chen, Yuke; Dou, Jianhong

    2016-05-01

    Tetralogy of Fallot (TOF) is the most common complex congenital heart disease (CHD) of the cyanotic type. Studies on ventricular functions have received an increasing amount of attention as the development of diagnosis and treatment technology for CHD continues to advance. Reasonable options for imaging examination and accurate assessment of preoperative and postoperative left ventricular functions of TOF patients are important in improving the cure rate of TOF radical operation, therapeutic evaluation, and judgment prognosis. Therefore, with the aid of dual-source computed tomography (DSCT), cardiac images with high temporal resolution and high definition, we measured the left ventricular time-volume curve using image data and calculating the left ventricular function parameters to conduct the preliminary evaluation on TOF patients. To comprehensively evaluate the cardiac function, the segmental ventricular wall function parameters were measured, and the measurement results were mapped to a bull's eye diagram to realize the standardization of segmental ventricular wall function evaluation. Finally, we introduced a new clustering method based on auto-regression model parameters and combined this method with Euclidean distance measurements to establish an intelligent diagnosis of TOF. The results of this experiment show that the TOF evaluation and the intelligent diagnostic methods proposed in this article are feasible. PMID:26496001

  20. Bragg reflection program

    This user's guide to the Bragg Reflection Program (BRP) is in the nature of an informal report. The general purpose of BRP is to scan a series of Bragg reflections automatically in order to obtain profiles and integrated intensities. The program is used in conjunction with the SUPERVISOR and READ packages, and the procedures for using it are similar to those for the Triple-Axis Control program. All the general features of the system, SUPERVISOR and READ packages as described in the Spectrometer Control Systems User's Guide are preserved. The presentation assumes that the reader is familiar with these. Sections are given on the READ package, execution and use, error messages, and output. A few sample problems are shown. (1 figure) (U.S.)

  1. IS CONSANGUINEOUS MARRIAGE RESPONSIBLE FOR CONGENITAL CARDIAC AND EXTRA-CARDIAC ANOMALIES?

    Nutan Nalini; Sudha

    2016-01-01

    BACKGROUND This article is about the stillbirth in which we found significant numbers of cardiac as well as extracardiac defects, in combination or separately. In this article, we would like to emphasize the anomalies found in consanguineous marriages. AIM To correlate the prevalence of cardiac as well as extracardiac anomalies in consanguineous marriages. Especially, here we would like to focus on the cardiac lesions. MATERIAL AND METHOD The study was ca...

  2. Service Learning Reflection Journal

    Sass, Margaret

    2013-01-01

    Service-Learning, a subset of service-engagement, is a course-based, credit-bearing educational experience in which students participate in an organized service activity that meets identified community needs; use knowledge and skills directly related to a course or discipline; and reflect on the service activity in such a way as to gain further understanding of course content, a broader appreciation of the discipline, and an enhanced sense of personal values and civic responsibility. This ...

  3. Towards a more accurate concept of fuels

    Full text: The introduction of LEU in Atucha and the approval of CARA show an advancement of the Argentine power stations fuels, which stimulate and show a direction to follow. In the first case, the use of enriched U fuel relax an important restriction related to neutronic economy; that means that it is possible to design less penalized fuels using more Zry. The second case allows a decrease in the lineal power of the rods, enabling a better performance of the fuel in normal and also in accident conditions. In this work we wish to emphasize this last point, trying to find a design in which the surface power of the rod is diminished. Hence, in accident conditions owing to lack of coolant, the cladding tube will not reach temperatures that will produce oxidation, with the corresponding H2 formation and with plasticity enough to form blisters, which will obstruct the reflooding and hydration that will produce fragility and rupture of the cladding tube, with the corresponding radioactive material dispersion. This work is oriented to find rods designs with quasi rectangular geometry to lower the surface power of the rods, in order to obtain a lower central temperature of the rod. Thus, critical temperatures will not be reached in case of lack of coolant. This design is becoming a reality after PPFAE's efforts in search of cladding tubes fabrication with different circumferential values, rectangular in particular. This geometry, with an appropriate pellet design, can minimize the pellet-cladding interaction and, through the accurate width election, non rectified pellets could be used. This means an important economy in pellets production, as well as an advance in the fabrication of fuels in gloves box and hot cells in the future. The sequence to determine critical geometrical parameters is described and some rod dispositions are explored

  4. Accurate orbit propagation with planetary close encounters

    Baù, Giulio; Milani Comparetti, Andrea; Guerra, Francesca

    2015-08-01

    We tackle the problem of accurately propagating the motion of those small bodies that undergo close approaches with a planet. The literature is lacking on this topic and the reliability of the numerical results is not sufficiently discussed. The high-frequency components of the perturbation generated by a close encounter makes the propagation particularly challenging both from the point of view of the dynamical stability of the formulation and the numerical stability of the integrator. In our approach a fixed step-size and order multistep integrator is combined with a regularized formulation of the perturbed two-body problem. When the propagated object enters the region of influence of a celestial body, the latter becomes the new primary body of attraction. Moreover, the formulation and the step-size will also be changed if necessary. We present: 1) the restarter procedure applied to the multistep integrator whenever the primary body is changed; 2) new analytical formulae for setting the step-size (given the order of the multistep, formulation and initial osculating orbit) in order to control the accumulation of the local truncation error and guarantee the numerical stability during the propagation; 3) a new definition of the region of influence in the phase space. We test the propagator with some real asteroids subject to the gravitational attraction of the planets, the Yarkovsky and relativistic perturbations. Our goal is to show that the proposed approach improves the performance of both the propagator implemented in the OrbFit software package (which is currently used by the NEODyS service) and of the propagator represented by a variable step-size and order multistep method combined with Cowell's formulation (i.e. direct integration of position and velocity in either the physical or a fictitious time).

  5. Accurate paleointensities - the multi-method approach

    de Groot, Lennart

    2016-04-01

    The accuracy of models describing rapid changes in the geomagnetic field over the past millennia critically depends on the availability of reliable paleointensity estimates. Over the past decade methods to derive paleointensities from lavas (the only recorder of the geomagnetic field that is available all over the globe and through geologic times) have seen significant improvements and various alternative techniques were proposed. The 'classical' Thellier-style approach was optimized and selection criteria were defined in the 'Standard Paleointensity Definitions' (Paterson et al, 2014). The Multispecimen approach was validated and the importance of additional tests and criteria to assess Multispecimen results must be emphasized. Recently, a non-heating, relative paleointensity technique was proposed -the pseudo-Thellier protocol- which shows great potential in both accuracy and efficiency, but currently lacks a solid theoretical underpinning. Here I present work using all three of the aforementioned paleointensity methods on suites of young lavas taken from the volcanic islands of Hawaii, La Palma, Gran Canaria, Tenerife, and Terceira. Many of the sampled cooling units are <100 years old, the actual field strength at the time of cooling is therefore reasonably well known. Rather intuitively, flows that produce coherent results from two or more different paleointensity methods yield the most accurate estimates of the paleofield. Furthermore, the results for some flows pass the selection criteria for one method, but fail in other techniques. Scrutinizing and combing all acceptable results yielded reliable paleointensity estimates for 60-70% of all sampled cooling units - an exceptionally high success rate. This 'multi-method paleointensity approach' therefore has high potential to provide the much-needed paleointensities to improve geomagnetic field models for the Holocene.

  6. Towards Accurate Application Characterization for Exascale (APEX)

    Hammond, Simon David [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    Sandia National Laboratories has been engaged in hardware and software codesign activities for a number of years, indeed, it might be argued that prototyping of clusters as far back as the CPLANT machines and many large capability resources including ASCI Red and RedStorm were examples of codesigned solutions. As the research supporting our codesign activities has moved closer to investigating on-node runtime behavior a nature hunger has grown for detailed analysis of both hardware and algorithm performance from the perspective of low-level operations. The Application Characterization for Exascale (APEX) LDRD was a project concieved of addressing some of these concerns. Primarily the research was to intended to focus on generating accurate and reproducible low-level performance metrics using tools that could scale to production-class code bases. Along side this research was an advocacy and analysis role associated with evaluating tools for production use, working with leading industry vendors to develop and refine solutions required by our code teams and to directly engage with production code developers to form a context for the application analysis and a bridge to the research community within Sandia. On each of these accounts significant progress has been made, particularly, as this report will cover, in the low-level analysis of operations for important classes of algorithms. This report summarizes the development of a collection of tools under the APEX research program and leaves to other SAND and L2 milestone reports the description of codesign progress with Sandia’s production users/developers.

  7. Accurate hydrocarbon estimates attained with radioactive isotope

    To make accurate economic evaluations of new discoveries, an oil company needs to know how much gas and oil a reservoir contains. The porous rocks of these reservoirs are not completely filled with gas or oil, but contain a mixture of gas, oil and water. It is extremely important to know what volume percentage of this water--called connate water--is contained in the reservoir rock. The percentage of connate water can be calculated from electrical resistivity measurements made downhole. The accuracy of this method can be improved if a pure sample of connate water can be analyzed or if the chemistry of the water can be determined by conventional logging methods. Because of the similarity of the mud filtrate--the water in a water-based drilling fluid--and the connate water, this is not always possible. If the oil company cannot distinguish between connate water and mud filtrate, its oil-in-place calculations could be incorrect by ten percent or more. It is clear that unless an oil company can be sure that a sample of connate water is pure, or at the very least knows exactly how much mud filtrate it contains, its assessment of the reservoir's water content--and consequently its oil or gas content--will be distorted. The oil companies have opted for the Repeat Formation Tester (RFT) method. Label the drilling fluid with small doses of tritium--a radioactive isotope of hydrogen--and it will be easy to detect and quantify in the sample

  8. Fast, accurate standardless XRF analysis with IQ+

    Full text: Due to both chemical and physical effects, the most accurate XRF data are derived from calibrations set up using in-type standards, necessitating some prior knowledge of the samples being analysed. Whilst this is often the case for routine samples, particularly in production control, for completely unknown samples the identification and availability of in-type standards can be problematic. Under these circumstances standardless analysis can offer a viable solution. Successful analysis of completely unknown samples requires a complete chemical overview of the speciemen together with the flexibility of a fundamental parameters (FP) algorithm to handle wide-ranging compositions. Although FP algorithms are improving all the time, most still require set-up samples to define the spectrometer response to a particular element. Whilst such materials may be referred to as standards, the emphasis in this kind of analysis is that only a single calibration point is required per element and that the standard chosen does not have to be in-type. The high sensitivities of modern XRF spectrometers, together with recent developments in detector counting electronics that possess a large dynamic range and high-speed data processing capacity bring significant advances to fast, standardless analysis. Illustrated with a tantalite-columbite heavy-mineral concentrate grading use-case, this paper will present the philosophy behind the semi-quantitative IQ+ software and the required hardware. This combination can give a rapid scan-based overview and quantification of the sample in less than two minutes, together with the ability to define channels for specific elements of interest where higher accuracy and lower levels of quantification are required. The accuracy, precision and limitations of standardless analysis will be assessed using certified reference materials of widely differing chemical and physical composition. Copyright (2002) Australian X-ray Analytical Association Inc

  9. Short-term Exposure to Microgravity and the Associated Risk of Sudden Cardiac Arrest: Implications for Commercial Spaceflight

    Laing, Kevin J. C.; Russamono, Thais

    2013-02-01

    The likelihood of trained astronauts developing a life threatening cardiac event during spaceflight is relatively rare, whilst the incidence in untrained individuals is unknown. Space tourists who live a sedentary lifestyle have reduced cardiovascular function, but the associated danger of sudden cardiac arrest (SCA) during a suborbital spaceflight (SOSF) is unclear. Risk during SOSF was examined by reviewing several microgravity studies and methods of determining poor cardiovascular condition. Accurately assessing cardiovascular function and improving baroreceptor sensitivity through exercise is suggested to reduce the incidence of SCA during future SOSFs. Future studies will benefit from past participants sharing medical history; allowing creation of risk profiles and suitable guidelines.

  10. Reflection Revisited: The Class Collage

    Sommers, Jeff

    2011-01-01

    Through the regular use of what Donald Schon has termed reflection-in-action and reflection-on-action, students can learn to improve their "reflection-in-presentation," in Kathleen Blake Yancey's term. Students are often asked to do this type of reflection-in-presentation as a capstone to first-year or basic writing courses. However, a number of…

  11. My Reflective Practice as Research.

    Pereira, Marcia A.

    1999-01-01

    Using Schon's concepts and definition of reflective practice, this article elaborates a model used to analyze the author's own processes of "reflection-in-action" and "reflection-on-action" in teaching first-year architectural students. Emphasizes the importance of the concept of "role-frame" in informing the whole reflective process. (EV)

  12. Subcutaneous Tissue Thickness is an Independent Predictor of Image Noise in Cardiac CT

    Staniak, Henrique Lane; Sharovsky, Rodolfo [Hospital Universitário - Universidade de São Paulo, São Paulo, SP (Brazil); Pereira, Alexandre Costa [Hospital das Clínicas - Universidade de São Paulo, São Paulo, SP (Brazil); Castro, Cláudio Campi de; Benseñor, Isabela M.; Lotufo, Paulo A. [Hospital Universitário - Universidade de São Paulo, São Paulo, SP (Brazil); Faculdade de Medicina - Universidade de São Paulo, São Paulo, SP (Brazil); Bittencourt, Márcio Sommer, E-mail: msbittencourt@mail.harvard.edu [Hospital Universitário - Universidade de São Paulo, São Paulo, SP (Brazil)

    2014-01-15

    Few data on the definition of simple robust parameters to predict image noise in cardiac computed tomography (CT) exist. To evaluate the value of a simple measure of subcutaneous tissue as a predictor of image noise in cardiac CT. 86 patients underwent prospective ECG-gated coronary computed tomographic angiography (CTA) and coronary calcium scoring (CAC) with 120 kV and 150 mA. The image quality was objectively measured by the image noise in the aorta in the cardiac CTA, and low noise was defined as noise < 30HU. The chest anteroposterior diameter and lateral width, the image noise in the aorta and the skin-sternum (SS) thickness were measured as predictors of cardiac CTA noise. The association of the predictors and image noise was performed by using Pearson correlation. The mean radiation dose was 3.5 ± 1.5 mSv. The mean image noise in CT was 36.3 ± 8.5 HU, and the mean image noise in non-contrast scan was 17.7 ± 4.4 HU. All predictors were independently associated with cardiac CTA noise. The best predictors were SS thickness, with a correlation of 0.70 (p < 0.001), and noise in the non-contrast images, with a correlation of 0.73 (p < 0.001). When evaluating the ability to predict low image noise, the areas under the ROC curve for the non-contrast noise and for the SS thickness were 0.837 and 0.864, respectively. Both SS thickness and CAC noise are simple accurate predictors of cardiac CTA image noise. Those parameters can be incorporated in standard CT protocols to adequately adjust radiation exposure.

  13. Subcutaneous Tissue Thickness is an Independent Predictor of Image Noise in Cardiac CT

    Few data on the definition of simple robust parameters to predict image noise in cardiac computed tomography (CT) exist. To evaluate the value of a simple measure of subcutaneous tissue as a predictor of image noise in cardiac CT. 86 patients underwent prospective ECG-gated coronary computed tomographic angiography (CTA) and coronary calcium scoring (CAC) with 120 kV and 150 mA. The image quality was objectively measured by the image noise in the aorta in the cardiac CTA, and low noise was defined as noise < 30HU. The chest anteroposterior diameter and lateral width, the image noise in the aorta and the skin-sternum (SS) thickness were measured as predictors of cardiac CTA noise. The association of the predictors and image noise was performed by using Pearson correlation. The mean radiation dose was 3.5 ± 1.5 mSv. The mean image noise in CT was 36.3 ± 8.5 HU, and the mean image noise in non-contrast scan was 17.7 ± 4.4 HU. All predictors were independently associated with cardiac CTA noise. The best predictors were SS thickness, with a correlation of 0.70 (p < 0.001), and noise in the non-contrast images, with a correlation of 0.73 (p < 0.001). When evaluating the ability to predict low image noise, the areas under the ROC curve for the non-contrast noise and for the SS thickness were 0.837 and 0.864, respectively. Both SS thickness and CAC noise are simple accurate predictors of cardiac CTA image noise. Those parameters can be incorporated in standard CT protocols to adequately adjust radiation exposure

  14. Polarizer reflectivity variations

    On Shiva the beam energy along the chain is monitored using available reflections and/or transmission through beam steering, splitting, and polarizing optics without the intrusion of any additional glass for diagnostics. On the preamp table the diagnostic signal is obtained from the signal transmitted through turning mirrors. At the input of each chain the signal is obtained from the transmission through one of the mirrors used for the chain input alignment sensor (CHIP). At the chain output the transmission through the final turning mirror is used. These diagnostics have proved stable and reliable. However, one of the prime diagnostic locations is at the output of the beta rod. The energy at this location is measured by collecting small reflections from the last polarizer surface of the beta Pockels cell polarizer package. Unfortunately, calibration of this diagnostic has varied randomly, seldom remaining stable for a week or more. The cause of this fluctuation has been investigated for the past year and'it has been discovered that polarizer reflectivity varies with humidity. This report will deal with the possible causes that were investigated, the evidence that humidity is causing the variation, and the associated mechanism

  15. Faulty cardiac repolarization reserve in alternating hemiplegia of childhood broadens the phenotype

    Jaffer, Fatima; Avbersek, Andreja; Vavassori, Rosaria; Fons, Carmen; Campistol, Jaume; Stagnaro, Michela; De Grandis, Elisa; Veneselli, Edvige; Rosewich, Hendrik; Gianotta, Melania; Zucca, Claudio; Ragona, Francesca; Granata, Tiziana; Nardocci, Nardo; Mikati, Mohamed; Helseth, Ashley R.; Boelman, Cyrus; Minassian, Berge A.; Johns, Sophia; Garry, Sarah I.; Scheffer, Ingrid E.; Gourfinkel-An, Isabelle; Carrilho, Ines; Aylett, Sarah E.; Parton, Matthew; Hanna, Michael G.; Houlden, Henry; Neville, Brian; Kurian, Manju A.; Novy, Jan; Sander, Josemir W.; Lambiase, Pier D.; Behr, Elijah R.; Schyns, Tsveta; Arzimanoglou, Alexis; Cross, J. Helen; Kaski, Juan P.

    2015-01-01

    , compared with those <16 (P = 0.0095), even with a specific mutation (p.D801N; P = 0.045). Dynamic, beat-to-beat or electrocardiogram-to-electrocardiogram, changes were noted, suggesting the prevalence of abnormalities was underestimated. Electrocardiogram changes occurred independently of seizures or plegic episodes. Electrocardiogram abnormalities are common in alternating hemiplegia, have characteristics reflecting those of inherited cardiac channelopathies and most likely amount to impaired repolarization reserve. The dynamic electrocardiogram and neurological features point to periodic systemic decompensation in ATP1A3-expressing organs. Cardiac dysfunction may account for some of the unexplained premature mortality of alternating hemiplegia. Systematic cardiac investigation is warranted in alternating hemiplegia of childhood, as cardiac arrhythmic morbidity and mortality are potentially preventable. PMID:26297560

  16. Quantification in non-invasive cardiac imaging: CT and MR

    Rossi, Alexia

    2013-01-01

    markdownabstract__Abstract__ The diagnosis and management of cardiac disease require a precise assessment of morphological and functional cardiac parameters. This thesis is divided in three parts. Part I emphasizes the role of cardiac computed tomography (CT) in the diagnosis of patients with ischemic heart disease. Part 2 describes the role of cardiac magnetic resonance (CMR) and cardiac CT in the diagnosis, interventional planning, and follow-up of patients with aortic valve stenosis. Part ...

  17. Evaluating the Cancer Therapeutic Potential of Cardiac Glycosides

    José Manuel Calderón-Montaño; Estefanía Burgos-Morón; Manuel Luis Orta; Dolores Maldonado-Navas; Irene García-Domínguez; Miguel López-Lázaro

    2014-01-01

    Cardiac glycosides, also known as cardiotonic steroids, are a group of natural products that share a steroid-like structure with an unsaturated lactone ring and the ability to induce cardiotonic effects mediated by a selective inhibition of the Na+/K+-ATPase. Cardiac glycosides have been used for many years in the treatment of cardiac congestion and some types of cardiac arrhythmias. Recent data suggest that cardiac glycosides may also be useful in the treatment of cancer. These compounds typ...

  18. Partial reflections of radio waves from the lower ionosphere

    Connolly, D. J.; Tanenbaum, S. B.

    1972-01-01

    The addition of phase difference measurements to partial reflection experiments is discussed, and some advantages of measuring electron density this way are pointed out. The additional information obtained reduces the requirement for an accurate predetermination of collision frequency. Calculations are also made to estimate the errors expected in partial-reflection experiments due to the assumption of Fresnel reflection and to the neglect of coupling between modes. In both cases, the errors are found to be of the same order as known errors in the measurements due to current instrumental limitations.

  19. Symptomatic cardiac amyloidosis in an American family

    This report describes an American family with a high incidence of symptomatic cardiac amyloidosis among four siblings, and explores the role of echocardiography and technetium pyrophosphate myocardial scintigraphy in the detection of this infiltrative cardiomyopathy within the involved family

  20. Cardiac morbidity risk and depression and anxiety

    Tully, Phillip J; Pedersen, Susanne S.; Winefield, Helen R;

    2011-01-01

    The aim of this study was to examine depression and anxiety disorders and their characteristic symptoms (anhedonia/low positive affect and anxious arousal, respectively), along with measures of state negative affect (NA) and Type D personality, in relation to cardiac surgery related morbidity...... personality traits were differentially associated with post-cardiac surgery morbidity outcomes independent of cardiac surgery morbidity risk factors. Concurrent investigation of depression and anxiety with respect to cardiac outcomes warrants further research........ Patients awaiting elective coronary artery bypass graft surgery (n=158; 20.9% female; 11.4% concomitant valve surgery; age M=64.7, SD=10.6) underwent the structured MINI International Neuropsychiatric Interview to determine current affective disorders. Patients also completed the Mood and Anxiety Symptom...