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Sample records for aortic input function

  1. Computing Functions by Approximating the Input

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    Goldberg, Mayer

    2012-01-01

    In computing real-valued functions, it is ordinarily assumed that the input to the function is known, and it is the output that we need to approximate. In this work, we take the opposite approach: we show how to compute the values of some transcendental functions by approximating the input to these functions, and obtaining exact answers for their…

  2. Cellular regulation of the structure and function of aortic valves

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    Ismail El-Hamamsy

    2010-01-01

    Full Text Available The aortic valve was long considered a passive structure that opens and closes in response to changes in transvalvular pressure. Recent evidence suggests that the aortic valve performs highly sophisticated functions as a result of its unique microscopic structure. These functions allow it to adapt to its hemodynamic and mechanical environment. Understanding the cellular and molecular mechanisms involved in normal valve physiology is essential to elucidate the mechanisms behind valve disease. We here review the structure and developmental biology of aortic valves; we examine the role of its cellular parts in regulating its function and describe potential pathophysiological and clinical implications.

  3. Existence conditions for unknown input functional observers

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    Fernando, T.; MacDougall, S.; Sreeram, V.; Trinh, H.

    2013-01-01

    This article presents necessary and sufficient conditions for the existence and design of an unknown input Functional observer. The existence of the observer can be verified by computing a nullspace of a known matrix and testing some matrix rank conditions. The existence of the observer does not require the satisfaction of the observer matching condition (i.e. Equation (16) in Hou and Muller 1992, 'Design of Observers for Linear Systems with Unknown Inputs', IEEE Transactions on Automatic Control, 37, 871-875), is not limited to estimating scalar functionals and allows for arbitrary pole placement. The proposed observer always exists when a state observer exists for the unknown input system, and furthermore, the proposed observer can exist even in some instances when an unknown input state observer does not exist.

  4. Significance of input correlations in striatal function.

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    Man Yi Yim

    2011-11-01

    Full Text Available The striatum is the main input station of the basal ganglia and is strongly associated with motor and cognitive functions. Anatomical evidence suggests that individual striatal neurons are unlikely to share their inputs from the cortex. Using a biologically realistic large-scale network model of striatum and cortico-striatal projections, we provide a functional interpretation of the special anatomical structure of these projections. Specifically, we show that weak pairwise correlation within the pool of inputs to individual striatal neurons enhances the saliency of signal representation in the striatum. By contrast, correlations among the input pools of different striatal neurons render the signal representation less distinct from background activity. We suggest that for the network architecture of the striatum, there is a preferred cortico-striatal input configuration for optimal signal representation. It is further enhanced by the low-rate asynchronous background activity in striatum, supported by the balance between feedforward and feedback inhibitions in the striatal network. Thus, an appropriate combination of rates and correlations in the striatal input sets the stage for action selection presumably implemented in the basal ganglia.

  5. Aortic Blood Flow Reversal Determines Renal Function: Potential Explanation for Renal Dysfunction Caused by Aortic Stiffening in Hypertension.

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    Hashimoto, Junichiro; Ito, Sadayoshi

    2015-07-01

    Aortic stiffness determines the glomerular filtration rate (GFR) and predicts the progressive decline of the GFR. However, the underlying pathophysiological mechanism remains obscure. Recent evidence has shown a close link between aortic stiffness and the bidirectional (systolic forward and early diastolic reverse) flow characteristics. We hypothesized that the aortic stiffening-induced renal dysfunction is attributable to altered central flow dynamics. In 222 patients with hypertension, Doppler velocity waveforms were recorded at the proximal descending aorta to calculate the reverse/forward flow ratio. Tonometric waveforms were recorded to measure the carotid-femoral (aortic) and carotid-radial (peripheral) pulse wave velocities, to estimate the aortic pressure from the radial waveforms, and to compute the aortic characteristic impedance. In addition, renal hemodynamics was evaluated by duplex ultrasound. The estimated GFR was inversely correlated with the aortic pulse wave velocity, reverse/forward flow ratio, pulse pressure, and characteristic impedance, whereas it was not correlated with the peripheral pulse wave velocity or mean arterial pressure. The association between aortic pulse wave velocity and estimated GFR was independent of age, diabetes mellitus, hypercholesterolemia, and antihypertensive medication. However, further adjustment for the aortic reverse/forward flow ratio and pulse pressure substantially weakened this association, and instead, the reverse/forward flow ratio emerged as the strongest determinant of estimated GFR (P=0.001). A higher aortic reverse/forward flow ratio was also associated with lower intrarenal forward flow velocities. These results suggest that an increase in aortic flow reversal (ie, retrograde flow from the descending thoracic aorta toward the aortic arch), caused by aortic stiffening and impedance mismatch, reduces antegrade flow into the kidney and thereby deteriorates renal function.

  6. Solar wind-magnetosphere energy input functions

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    Bargatze, L.F.; McPherron, R.L.; Baker, D.N.

    1985-01-01

    A new formula for the solar wind-magnetosphere energy input parameter, P/sub i/, is sought by applying the constraints imposed by dimensional analysis. Applying these constraints yields a general equation for P/sub i/ which is equal to rho V/sup 3/l/sub CF//sup 2/F(M/sub A/,theta) where, rho V/sup 3/ is the solar wind kinetic energy density and l/sub CF//sup 2/ is the scale size of the magnetosphere's effective energy ''collection'' region. The function F which depends on M/sub A/, the Alfven Mach number, and on theta, the interplanetary magnetic field clock angle is included in the general equation for P/sub i/ in order to model the magnetohydrodynamic processes which are responsible for solar wind-magnetosphere energy transfer. By assuming the form of the function F, it is possible to further constrain the formula for P/sub i/. This is accomplished by using solar wind data, geomagnetic activity indices, and simple statistical methods. It is found that P/sub i/ is proportional to (rho V/sup 2/)/sup 1/6/VBG(theta) where, rho V/sup 2/ is the solar wind dynamic pressure and VBG(theta) is a rectified version of the solar wind motional electric field. Furthermore, it is found that G(theta), the gating function which modulates the energy input to the magnetosphere, is well represented by a ''leaky'' rectifier function such as sin/sup 4/(theta/2). This function allows for enhanced energy input when the interplanetary magnetic field is oriented southward. This function also allows for some energy input when the interplanetary magnetic field is oriented northward. 9 refs., 4 figs.

  7. FUNCTIONAL AORTIC STIFFNESS:ROLE OF CD4+ T LYMPHOCYTES

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    Beenish A. Majeed

    2015-08-01

    Full Text Available The immune system is suggested to be essential in vascular remodeling and stiffening. To study the dependence upon lymphocytes in vascular stiffening, we compared an angiotensin II-model of vascular stiffening in normal C57BL/6J mice with lymphocyte-deficient RAG 1-/- mice and additionally characterized the component of vascular stiffness due to vasoconstriction versus vascular remodeling. Chronic angiotensin II increased aortic pulse wave velocity, effective wall stiffness, and effective Young’s modulus in C57BL/6J mice by 3-fold but caused no change in the RAG 1-/- mice. These functional measurements were supported by aortic morphometric analysis. Adoptive transfer of CD4+ T helper lymphocytes restored the angiotensin II-mediated aortic stiffening in the RAG 1-/- mice. In order to account for the hydraulic versus material effects of angiotensin II on pulse wave velocity, subcutaneous osmotic pumps were removed after 21 days of angiotensin II-infusion in the WT mice to achieve normotensive values. The pulse wave velocity decreased from 3- to 2-fold above baseline values up to 7 days following pump removal. This study supports the pivotal role of the CD4+ T-lymphocytes in angiotensin II-mediated vascular stiffening and that angiotensin II-mediated aortic stiffening is due to the additive effect of active vascular smooth muscle vasoconstriction and vascular remodeling.

  8. Recurrent gain-of-function mutation in PRKG1 causes thoracic aortic aneurysms and acute aortic dissections.

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    Guo, Dong-chuan; Regalado, Ellen; Casteel, Darren E; Santos-Cortez, Regie L; Gong, Limin; Kim, Jeong Joo; Dyack, Sarah; Horne, S Gabrielle; Chang, Guijuan; Jondeau, Guillaume; Boileau, Catherine; Coselli, Joseph S; Li, Zhenyu; Leal, Suzanne M; Shendure, Jay; Rieder, Mark J; Bamshad, Michael J; Nickerson, Deborah A; Kim, Choel; Milewicz, Dianna M

    2013-08-08

    Gene mutations that lead to decreased contraction of vascular smooth-muscle cells (SMCs) can cause inherited thoracic aortic aneurysms and dissections. Exome sequencing of distant relatives affected by thoracic aortic disease and subsequent Sanger sequencing of additional probands with familial thoracic aortic disease identified the same rare variant, PRKG1 c.530G>A (p.Arg177Gln), in four families. This mutation segregated with aortic disease in these families with a combined two-point LOD score of 7.88. The majority of affected individuals presented with acute aortic dissections (63%) at relatively young ages (mean 31 years, range 17-51 years). PRKG1 encodes type I cGMP-dependent protein kinase (PKG-1), which is activated upon binding of cGMP and controls SMC relaxation. Although the p.Arg177Gln alteration disrupts binding to the high-affinity cGMP binding site within the regulatory domain, the altered PKG-1 is constitutively active even in the absence of cGMP. The increased PKG-1 activity leads to decreased phosphorylation of the myosin regulatory light chain in fibroblasts and is predicted to cause decreased contraction of vascular SMCs. Thus, identification of a gain-of-function mutation in PRKG1 as a cause of thoracic aortic disease provides further evidence that proper SMC contractile function is critical for maintaining the integrity of the thoracic aorta throughout a lifetime.

  9. Are Financial Variables Inputs in Delivered Production Functions? Are Financial Variables Inputs in Delivered Production Functions?

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    Miguel Kiguel

    1995-03-01

    Full Text Available Fischer's classic (1974 paper develops conditions under which it is appropriate to use money as an input in a 'delivered' production function. In this paper, we extend Fischer's model I (the Baumol-Tobin inventory approach by incorporating credit into the analysis. Our investigation of the extended model brings out a very restrictive but necessary implicit assumption employed by Fischer to treat money as an input. Namely. that there exists a binding constraint on the use of money! A similar result holds for our more general model. Fischer's classic (1974 paper develops conditions under which it is appropriate to use money as an input in a 'delivered' production function. In this paper, we extend Fischer's model I (the Baumol-Tobin inventory approach by incorporating credit into the analysis. Our investigation of the extended model brings out a very restrictive but necessary implicit assumption employed by Fischer to treat money as an input. Namely. that there exists a binding constraint on the use of money! A similar result holds for our more general model.

  10. Acute regional improvement of myocardial function after interventional transfemoral aortic valve replacement in aortic stenosis: A speckle tracking echocardiography study

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    Schattke Sebastian

    2012-03-01

    Full Text Available Abstract Background Transcatheter aortic valve implantation (TAVI is a promising therapy for patients with severe aortic stenosis (AS and high perioperative risk. New echocardiographic methods, including 2D Strain analysis, allow the more accurate measurement of left ventricular (LV systolic function. The goal of this study was to describe the course of LV reverse remodelling immediately after TAVI in a broad spectrum of patients with symptomatic severe aortic valve stenosis. Methods Thirty consecutive patients with symptomatic aortic valve stenosis and preserved LVEF underwent transfemoral aortic valve implantation. We performed echocardiography at baseline and one week after TAVI. Echocardiography included standard 2D and Doppler analysis of global systolic and diastolic function as well as 2D Strain measurements of longitudinal, radial and circumferential LV motion and Tissue Doppler echocardiography. Results The baseline biplane LVEF was 57 ± 8.2%, the mean pressure gradient was 46.8 ± 17.2 mmHg and the mean valve area was 0.73 ± 0.27 cm2. The average global longitudinal 2D strain of the left ventricle improved significantly from -15.1 (± 3.0 to -17.5 (± 2.4 % (p Conclusion There is an acute improvement of myocardial longitudinal systolic function of the basal and medial segments measured by 2D Strain analysis immediately after TAVI. The radial, circumferential strain and LVEF does not change significantly in all patients acutely after TAVI. These data suggest that sensitive new echo methods can reliably detect early regional changes of myocardial function after TAVI before benefits in LVEF are detectable.

  11. Dynamic heart phantom with functional mitral and aortic valves

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    Vannelli, Claire; Moore, John; McLeod, Jonathan; Ceh, Dennis; Peters, Terry

    2015-03-01

    Cardiac valvular stenosis, prolapse and regurgitation are increasingly common conditions, particularly in an elderly population with limited potential for on-pump cardiac surgery. NeoChord©, MitraClipand numerous stent-based transcatheter aortic valve implantation (TAVI) devices provide an alternative to intrusive cardiac operations; performed while the heart is beating, these procedures require surgeons and cardiologists to learn new image-guidance based techniques. Developing these visual aids and protocols is a challenging task that benefits from sophisticated simulators. Existing models lack features needed to simulate off-pump valvular procedures: functional, dynamic valves, apical and vascular access, and user flexibility for different activation patterns such as variable heart rates and rapid pacing. We present a left ventricle phantom with these characteristics. The phantom can be used to simulate valvular repair and replacement procedures with magnetic tracking, augmented reality, fluoroscopy and ultrasound guidance. This tool serves as a platform to develop image-guidance and image processing techniques required for a range of minimally invasive cardiac interventions. The phantom mimics in vivo mitral and aortic valve motion, permitting realistic ultrasound images of these components to be acquired. It also has a physiological realistic left ventricular ejection fraction of 50%. Given its realistic imaging properties and non-biodegradable composition—silicone for tissue, water for blood—the system promises to reduce the number of animal trials required to develop image guidance applications for valvular repair and replacement. The phantom has been used in validation studies for both TAVI image-guidance techniques1, and image-based mitral valve tracking algorithms2.

  12. Simulation study and function analysis of the dynamic aortic valve

    Institute of Scientific and Technical Information of China (English)

    XIA Dongdong; BAI Jing

    2006-01-01

    The dynamic aortic valve (DAV) is a new left ventricular assist device, a micro-axial blood pump implemented at the position of the aortic valve, pumping blood from the left ventricle into the aortic artery. The present dynamic aortic valve operates at 7 different rotation speeds, ranging from 3000 r/min (speed 1) to 9000 r/min (speed 7). Because in vivo experiments need a lot of live animals and take a long period of time, modeling and simulation have been widely used to simulate and analyze hydra-dynamic property of the DAV and its assisting effects. With the measurements from the mock circulatory loop, a mathematic model of the DAV is established and embedded into the previously developed canine circulatory system. Using this model, the effect of the DAV on the failing heart at each rotation speed level is investigated. The vital cardiac variables are computed and compared with in vivo experimental results, which are in good agreement with an acceptable difference mostly 15 %. The establishment of the DAV model and its simulation are useful for further improvement of the DAV device.

  13. Aging impairs smooth muscle-mediated regulation of aortic stiffness: a defect in shock absorption function?

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    Gao, Yuan Z; Saphirstein, Robert J; Yamin, Rina; Suki, Bela; Morgan, Kathleen G

    2014-10-15

    Increased aortic stiffness is an early and independent biomarker of cardiovascular disease. Here we tested the hypothesis that vascular smooth muscle cells (VSMCs) contribute significantly to aortic stiffness and investigated the mechanisms involved. The relative contributions of VSMCs, focal adhesions (FAs), and matrix to stiffness in mouse aorta preparations at optimal length and with confirmed VSMC viability were separated by the use of small-molecule inhibitors and activators. Using biomechanical methods designed for minimal perturbation of cellular function, we directly quantified changes with aging in aortic material stiffness. An alpha adrenoceptor agonist, in the presence of N(G)-nitro-l-arginine methyl ester (l-NAME) to remove interference of endothelial nitric oxide, increases stiffness by 90-200% from baseline in both young and old mice. Interestingly, increases are robustly suppressed by the Src kinase inhibitor PP2 in young but not old mice. Phosphotyrosine screening revealed, with aging, a biochemical signature of markedly impaired agonist-induced FA remodeling previously associated with Src signaling. Protein expression measurement confirmed a decrease in Src expression with aging. Thus we report here an additive model for the in vitro biomechanical components of the mouse aortic wall in which 1) VSMCs are a surprisingly large component of aortic stiffness at physiological lengths and 2) regulation of the VSMC component through FA signaling and hence plasticity is impaired with aging, diminishing the aorta's normal shock absorption function in response to stressors.

  14. How do mammillary body inputs contribute to anterior thalamic function?

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    Dillingham, Christopher M.; Frizzati, Aura; Nelson, Andrew J.D.; Vann, Seralynne D.

    2015-01-01

    It has long been assumed that the main function of the mammillary bodies is to provide a relay for indirect hippocampal inputs to the anterior thalamic nuclei. Such models afford the mammillary bodies no independent role in memory and overlook the importance of their other, non-hippocampal, inputs. This review focuses on recent advances that herald a new understanding of the importance of the mammillary bodies, and their inputs from the limbic midbrain, for anterior thalamic function. It has become apparent that the mammillary bodies’ contribution to memory is not dependent on afferents from the subicular complex. Rather, the ventral tegmental nucleus of Gudden is a vital source of inputs that support memory processes within the medial mammillary bodies. In parallel, the lateral mammillary bodies, via their connections with the dorsal tegmental nucleus of Gudden, are critical for generating head-direction signals. These two parallel, but distinct, information streams converge on the anterior thalamic nuclei and support different aspects of spatial memory. PMID:25107491

  15. Quantitative amyloid imaging using image-derived arterial input function.

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    Yi Su

    Full Text Available Amyloid PET imaging is an indispensable tool widely used in the investigation, diagnosis and monitoring of Alzheimer's disease (AD. Currently, a reference region based approach is used as the mainstream quantification technique for amyloid imaging. This approach assumes the reference region is amyloid free and has the same tracer influx and washout kinetics as the regions of interest. However, this assumption may not always be valid. The goal of this work is to evaluate an amyloid imaging quantification technique that uses arterial region of interest as the reference to avoid potential bias caused by specific binding in the reference region. 21 participants, age 58 and up, underwent Pittsburgh compound B (PiB PET imaging and MR imaging including a time-of-flight (TOF MR angiography (MRA scan and a structural scan. FreeSurfer based regional analysis was performed to quantify PiB PET data. Arterial input function was estimated based on coregistered TOF MRA using a modeling based technique. Regional distribution volume (VT was calculated using Logan graphical analysis with estimated arterial input function. Kinetic modeling was also performed using the estimated arterial input function as a way to evaluate PiB binding (DVRkinetic without a reference region. As a comparison, Logan graphical analysis was also performed with cerebellar cortex as reference to obtain DVRREF. Excellent agreement was observed between the two distribution volume ratio measurements (r>0.89, ICC>0.80. The estimated cerebellum VT was in line with literature reported values and the variability of cerebellum VT in the control group was comparable to reported variability using arterial sampling data. This study suggests that image-based arterial input function is a viable approach to quantify amyloid imaging data, without the need of arterial sampling or a reference region. This technique can be a valuable tool for amyloid imaging, particularly in population where reference

  16. Quantitative amyloid imaging using image-derived arterial input function.

    Science.gov (United States)

    Su, Yi; Blazey, Tyler M; Snyder, Abraham Z; Raichle, Marcus E; Hornbeck, Russ C; Aldea, Patricia; Morris, John C; Benzinger, Tammie L S

    2015-01-01

    Amyloid PET imaging is an indispensable tool widely used in the investigation, diagnosis and monitoring of Alzheimer's disease (AD). Currently, a reference region based approach is used as the mainstream quantification technique for amyloid imaging. This approach assumes the reference region is amyloid free and has the same tracer influx and washout kinetics as the regions of interest. However, this assumption may not always be valid. The goal of this work is to evaluate an amyloid imaging quantification technique that uses arterial region of interest as the reference to avoid potential bias caused by specific binding in the reference region. 21 participants, age 58 and up, underwent Pittsburgh compound B (PiB) PET imaging and MR imaging including a time-of-flight (TOF) MR angiography (MRA) scan and a structural scan. FreeSurfer based regional analysis was performed to quantify PiB PET data. Arterial input function was estimated based on coregistered TOF MRA using a modeling based technique. Regional distribution volume (VT) was calculated using Logan graphical analysis with estimated arterial input function. Kinetic modeling was also performed using the estimated arterial input function as a way to evaluate PiB binding (DVRkinetic) without a reference region. As a comparison, Logan graphical analysis was also performed with cerebellar cortex as reference to obtain DVRREF. Excellent agreement was observed between the two distribution volume ratio measurements (r>0.89, ICC>0.80). The estimated cerebellum VT was in line with literature reported values and the variability of cerebellum VT in the control group was comparable to reported variability using arterial sampling data. This study suggests that image-based arterial input function is a viable approach to quantify amyloid imaging data, without the need of arterial sampling or a reference region. This technique can be a valuable tool for amyloid imaging, particularly in population where reference normalization may

  17. Left ventricular diastolic function is associated with symptom status in severe aortic valve stenosis

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    Dahl, Jordi S; Christensen, Nicolaj L; Videbæk, Lars

    2014-01-01

    BACKGROUND: In aortic valve stenosis (AS), the occurrence of heart failure symptoms does not always correlate with severity of valve stenosis and left ventricular (LV) function. Therefore, we tested the hypothesis that symptomatic patients with AS have impaired diastolic, longitudinal systolic fu...... for indices of AS severity. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00294775....

  18. Correlation of echocardiographic wall stress and left ventricular pressure and function in aortic stenosis.

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    DePace, N L; Ren, J F; Iskandrian, A S; Kotler, M N; Hakki, A H; Segal, B L

    1983-04-01

    Previous studies have suggested that left ventricular pressure (P) can be predicted in patients with aortic stenosis by the equation P = 235 h/r, where 235 is a constant peak wall stress (sigma), h is end-systolic wall thickness, and r is end-systolic dimension/2; h and r are measured by M-mode echocardiography. In 73 patients with aortic stenosis (valve area less than 0.7 cm2), measured and predicted left ventricular pressure correlated poorly (r = 0.17). The measured wall stress in our patients varied from 120 to 250 mm Hg in patients with normal left ventricular function and from 250 to 550 mm Hg in patients with abnormal function. The correlation between sigma and h was only fair (r = 0.53), because many patients had inappropriate left ventricular hypertrophy. There was a statistically significant correlation between ejection fraction and sigma (r = 0.62) and between ejection fraction and end-systolic dimension (r = -0.70), but there was considerable scatter of ejection fractions for any given end-systolic dimension. We conclude that sigma is not constant in aortic stenosis, and the use of a constant sigma to predict left ventricular pressure is unreliable; inappropriate left ventricular hypertrophy may explain why sigma is not constant. M-mode echocardiography is not reliable in assessing the severity of aortic stenosis in adults; such assessment requires precise measurements of pressure gradients and flow by cardiac catheterization.

  19. Morphological and functional evaluation of quadricuspid aortic valves using cardiac computed tomography

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    Song, In Young; Park, Jung Ah; Choi, Bo Hwa; Ko, Sung Min; Shin, Je Kyoun; Chee, Hyun Keun; KIm, Jun Seok [Konkuk University Medical Center, Konkuk University School of Medicine, Seoul (Korea, Republic of)

    2016-07-15

    The aim of this study was to identify the morphological and functional characteristics of quadricuspid aortic valves (QAV) on cardiac computed tomography (CCT). We retrospectively enrolled 11 patients with QAV. All patients underwent CCT and transthoracic echocardiography (TTE), and 7 patients underwent cardiovascular magnetic resonance (CMR). The presence and classification of QAV assessed by CCT was compared with that of TTE and intraoperative findings. The regurgitant orifice area (ROA) measured by CCT was compared with severity of aortic regurgitation (AR) by TTE and the regurgitant fraction (RF) by CMR. All of the patients had AR; 9 had pure AR, 1 had combined aortic stenosis and regurgitation, and 1 had combined subaortic stenosis and regurgitation. Two patients had a subaortic fibrotic membrane and 1 of them showed a subaortic stenosis. One QAV was misdiagnosed as tricuspid aortic valve on TTE. In accordance with the Hurwitz and Robert's classification, consensus was reached on the QAV classification between the CCT and TTE findings in 7 of 10 patients. The patients were classified as type A (n = 1), type B (n = 3), type C (n = 1), type D (n = 4), and type F (n = 2) on CCT. A very high correlation existed between ROA by CCT and RF by CMR (r = 0.99) but a good correlation existed between ROA by CCT and regurgitant severity by TTE (r = 0.62). Cardiac computed tomography provides comprehensive anatomical and functional information about the QAV.

  20. Morphological and Functional Evaluation of Quadricuspid Aortic Valves Using Cardiac Computed Tomography

    Energy Technology Data Exchange (ETDEWEB)

    Song, Inyoung; Park, Jung Ah; Choi, Bo Hwa; Ko, Sung Min [Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 05030 (Korea, Republic of); Shin, Je Kyoun; Chee, Hyun Keun; Kim, Jun Seok [Department of Thoracic Surgery, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 05030 (Korea, Republic of)

    2016-11-01

    The aim of this study was to identify the morphological and functional characteristics of quadricuspid aortic valves (QAV) on cardiac computed tomography (CCT). We retrospectively enrolled 11 patients with QAV. All patients underwent CCT and transthoracic echocardiography (TTE), and 7 patients underwent cardiovascular magnetic resonance (CMR). The presence and classification of QAV assessed by CCT was compared with that of TTE and intraoperative findings. The regurgitant orifice area (ROA) measured by CCT was compared with severity of aortic regurgitation (AR) by TTE and the regurgitant fraction (RF) by CMR. All of the patients had AR; 9 had pure AR, 1 had combined aortic stenosis and regurgitation, and 1 had combined subaortic stenosis and regurgitation. Two patients had a subaortic fibrotic membrane and 1 of them showed a subaortic stenosis. One QAV was misdiagnosed as tricuspid aortic valve on TTE. In accordance with the Hurwitz and Robert's classification, consensus was reached on the QAV classification between the CCT and TTE findings in 7 of 10 patients. The patients were classified as type A (n = 1), type B (n = 3), type C (n = 1), type D (n = 4), and type F (n = 2) on CCT. A very high correlation existed between ROA by CCT and RF by CMR (r = 0.99) but a good correlation existed between ROA by CCT and regurgitant severity by TTE (r = 0.62). Cardiac computed tomography provides comprehensive anatomical and functional information about the QAV.

  1. Low-flow aortic stenosis in asymptomatic patients: valvular-arterial impedance and systolic function from the SEAS Substudy

    DEFF Research Database (Denmark)

    Cramariuc, Dana; Cioffi, Giovanni; Rieck, Ashild E

    2009-01-01

    OBJECTIVES: This study sought to assess the impact of valvuloarterial impedance on left ventricular (LV) myocardial systolic function in asymptomatic aortic valve stenosis (AS). BACKGROUND: In atherosclerotic AS, LV global load consists of combined valvular and arterial resistance to LV ejection...... Ezetimibe in Aortic Stenosis) study evaluating placebo-controlled combined simvastatin and ezetimibe treatment in AS were used to assess LV global load as valvuloarterial impedance and LV myocardial function as stress-corrected midwall shortening. The study population was divided into tertiles of global...... preserved. (An Investigational Drug on Clinical Outcomes in Patients With Aortic Stenosis [Narrowing of the Major Blood Vessel of the Heart]; NCT00092677)....

  2. Relationships between retinal arteriole anatomy and aortic geometry and function and peripheral resistance in hypertensives.

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    Rosenbaum, David; Kachenoura, Nadjia; Koch, Edouard; Paques, Michel; Cluzel, Philippe; Redheuil, Alban; Girerd, Xavier

    2016-07-01

    Microvascular remodeling and large artery stiffness are key determinants of cardiovascular hemodynamics and can now be studied with new non-invasive methods. Our objective was to study the relationships between retinal arteriole anatomy and aortic geometry and function and peripheral resistance (total peripheral resistance (TPR)) in hypertensives. In 80 subjects (age 52±13 years; 53% males; including 23 normotensives and 57 hypertensives, among which 29 were uncontrolled hypertensives), we used: (1) the new non-invasive RTX1 adaptive optics (AO) camera (Imagine Eyes, Orsay, France) to measure the wall-to-lumen ratio (WLR) on retinal microvasculature; (2) cardiovascular magnetic resonance (CMR) imaging to assess aortic stiffness, geometry and cardiac output; and (3) the validated SphymoCor Xcel device to measure central blood pressure (BP) and carotido-femoral pulse wave velocity (Cf-PWV). TPR was calculated as the central mean BP/cardiac output ratio. WLR and TPR were significantly higher and aortic distensibility was significantly lower in hypertensives. Aortic dilation and arch elongation were found in uncontrolled hypertensives. In the univariate analysis, WLR was positively correlated with central BP (PTPR (PTPR (P=0.002) independent of age, BMI, gender, antihypertensive treatments, aortic diameter and central SBP. As expected, age was the major correlate of ascending aorta distensibility and Cf-PWV. New non-invasive vascular imaging methods are complementary for the detection of the deleterious effects of aging or high BP on large and small arteries. AO examination could represent a useful tool for the study and follow-up of microvasculature anatomical changes.

  3. Influence of St. Jude medical valve in patients with aortic stenosis and small aortic annulus on cardiac function and late survival result.

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    Natsuaki, Masafumi; Itoh, Tsuyoshi; Okazaki, Yukio; Takarabe, Kyoumi; Furukawa, Koujirou; Rikitake, Kazuhisa; Ohtubo, Satoshi

    2002-10-01

    This clinical study analyzes our experience of postoperative cardiac function and long-term survival rate in patients with aortic stenosis and small-size St. Jude Medical (SJM) valve. Sixty-eight patients who underwent aortic valve replacement by SJM valve were divided into two groups by preoperative aortic annulus diameter. Group 1 consisted of 44 patients with small aortic annulus and small-size SJM valve (19 mm or 21 mm). In Group 1, small SJM standard valves were implanted in 16 patients, and small SJM Hemodynamic Plus (HP) valves were implanted in 28 patients. Group 2 consisted of 24 patients with large-size SJM standard valve (23 mm or larger). Preoperative left ventricular mass index, left ventricular dimension, the dimension of ascending aorta, and body surface area were significantly smaller in Group 1 than in Group 2. Average age at surgery was older in Group 1 than in Group 2. Effective orifice area index of the SJM valve measured by the manufacturer's data was smaller in Group 1 than in Group 2. Postoperative left ventricular mass indexes of Group 1 (standard valve or HP valve) and Group 2 significantly decreased in comparison with the preoperative mass indexes. Postoperative left ventricular ejection fraction and the peak ejection rate of Group 1 were not different from those of Group 2. The 10 year survival rate of Group 1 was 79%, and the rate of Group 2 was 77%. At 10 years after surgery, freedom from valve-related complication of Group 1 was 80%, and freedom from complication of Group 2 was 81%. Our results demonstrated that small-size SJM valve afforded satisfactory long-term survival rate and valve-related event-free rate for elderly patients with small body surface area and small aortic annulus.

  4. Estimating Fast Neural Input Using Anatomical and Functional Connectivity.

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    Eriksson, David

    2016-01-01

    In the last 20 years there has been an increased interest in estimating signals that are sent between neurons and brain areas. During this time many new methods have appeared for measuring those signals. Here we review a wide range of methods for which connected neurons can be identified anatomically, by tracing axons that run between the cells, or functionally, by detecting if the activity of two neurons are correlated with a short lag. The signals that are sent between the neurons are represented by the activity in the neurons that are connected to the target population or by the activity at the corresponding synapses. The different methods not only differ in the accuracy of the signal measurement but they also differ in the type of signal being measured. For example, unselective recording of all neurons in the source population encompasses more indirect pathways to the target population than if one selectively record from the neurons that project to the target population. Infact, this degree of selectivity is similar to that of optogenetic perturbations; one can perturb selectively or unselectively. Thus it becomes possible to match a given signal measurement method with a signal perturbation method, something that allows for an exact input control to any neuronal population.

  5. Effect of carotid and aortic baroreceptors on cardiopulmonary reflex: the role of autonomic function

    Directory of Open Access Journals (Sweden)

    T.L. Fernandes

    2010-07-01

    Full Text Available We determined the sympathetic and parasympathetic control of heart rate (HR and the sensitivity of the cardiopulmonary receptors after selective carotid and aortic denervation. We also investigated the participation of the autonomic nervous system in the Bezold-Jarish reflex after selective removal of aortic and carotid baroreceptors. Male Wistar rats (220-270 g were divided into three groups: control (CG, N = 8, aortic denervation (AG, N = 5 and carotid denervation (CAG, N = 9. AG animals presented increased arterial pressure (12% and HR (11% compared with CG, while CAG animals presented a reduction in arterial pressure (16% and unchanged HR compared with CG. The sequential blockade of autonomic effects by atropine and propranolol indicated a reduction in vagal function in CAG (a 50 and 62% reduction in vagal effect and tonus, respectively while AG showed an increase of more than 100% in sympathetic control of HR. The Bezold-Jarish reflex was evaluated using serotonin, which induced increased bradycardia and hypotension in AG and CAG, suggesting that the sensitivity of the cardiopulmonary reflex is augmented after selective denervation. Atropine administration abolished the bradycardic responses induced by serotonin in all groups; however, the hypotensive response was still increased in AG. Although the responses after atropine were lower than the responses before the drug, indicating a reduction in vagal outflow after selective denervation, our data suggest that both denervation procedures are associated with an increase in sympathetic modulation of the vessels, indicating that the sensitivity of the cardiopulmonary receptors was modulated by baroreceptor fibers.

  6. Aortic insufficiency

    Science.gov (United States)

    ... page, please enable JavaScript. Aortic insufficiency is a heart valve disease in which the aortic valve does not close ... aortic insufficiency Images Aortic insufficiency References Carabello BA. Valvular heart disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil ...

  7. Mitochondrial oxidative stress in aortic stiffening with age: the role of smooth muscle cell function.

    Science.gov (United States)

    OBJECTIVE: Age-related aortic stiffness is an independent risk factor for cardiovascular diseases. Although oxidative stress is implicated in aortic stiffness, the underlying molecular mechanisms remain unelucidated. Here, we examined the source of oxidative stress in aging and i...

  8. Plasticity of the cis-regulatory input function of a gene.

    Directory of Open Access Journals (Sweden)

    Avraham E Mayo

    2006-04-01

    Full Text Available The transcription rate of a gene is often controlled by several regulators that bind specific sites in the gene's cis-regulatory region. The combined effect of these regulators is described by a cis-regulatory input function. What determines the form of an input function, and how variable is it with respect to mutations? To address this, we employ the well-characterized lac operon of Escherichia coli, which has an elaborate input function, intermediate between Boolean AND-gate and OR-gate logic. We mapped in detail the input function of 12 variants of the lac promoter, each with different point mutations in the regulator binding sites, by means of accurate expression measurements from living cells. We find that even a few mutations can significantly change the input function, resulting in functions that resemble Pure AND gates, OR gates, or single-input switches. Other types of gates were not found. The variant input functions can be described in a unified manner by a mathematical model. The model also lets us predict which functions cannot be reached by point mutations. The input function that we studied thus appears to be plastic, in the sense that many of the mutations do not ruin the regulation completely but rather result in new ways to integrate the inputs.

  9. [Study of left ventricular function in valvular cardiopathies (mitral insufficiency and aortic insufficiency].

    Science.gov (United States)

    Herreman, F; Brun, P; Cannet, G; Savin, E; Vannier, D

    1974-10-01

    A study of the left ventricular function based on the haemodynamic data combined with those provided by biplane cineangiography was performed in 35 cases with left ventricular volume overload (20 cases of mitral incompetence and 15 of aortic insufficiency). The importance of the haemodynamic changes and of the adaptation mechanisms set up were described. The more intense dilatation-hypertrophy of aortic incompetence than of mitral incompetence plays an essential part. The role of Starling's mechanism is underlined. Estimation of the contractile value of the myocardium, taken into account the mechanical overload and the conditions of late-diastolic lengthening of the fibre and of impedance to left ventricular ejection was determined. An obvious myocardial failure, demonstrated in approximately one third of the cases, by determination of some contractility indices estimated in the ejection phase, Vf sigma max in particular, the only one valid in the presence of valvular regurgitation. In the other cases, the moderate decrease of myocardial contractility was masked by compensatory mechanisms.

  10. Aortic stiffness is associated with cardiac function and cerebral small vessel disease in patients with type 1 diabetes mellitus: assessment by magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Elderen, Saskia G.C. van; Brandts, A.; Westenberg, J.J.M.; Grond, J. van der; Buchem, M.A. van; Kroft, L.J.M.; Roos, A. de [Leiden University Medical Center, Department of Radiology, Leiden (Netherlands); Tamsma, J.T.; Romijn, J.A.; Smit, J.W.A. [Leiden University Medical Center, Department of Endocrinology, Leiden (Netherlands)

    2010-05-15

    To evaluate, with the use of magnetic resonance imaging (MRI), whether aortic pulse wave velocity (PWV) is associated with cardiac left ventricular (LV) function and mass as well as with cerebral small vessel disease in patients with type 1 diabetes mellitus (DM). We included 86 consecutive type 1 DM patients (49 male, mean age 46.9 {+-} 11.7 years) in a prospective, cross-sectional study. Exclusion criteria included aortic/heart disease and general MRI contra-indications. MRI of the aorta, heart and brain was performed for assessment of aortic PWV, as a marker of aortic stiffness, systolic LV function and mass, as well as for the presence of cerebral white matter hyperintensities (WMHs), microbleeds and lacunar infarcts. Multivariate linear or logistic regression was performed to analyse the association between aortic PWV and outcome parameters, with covariates defined as age, gender, mean arterial pressure, heart rate, BMI, smoking, DM duration and hypertension. Mean aortic PWV was 7.1 {+-} 2.5 m/s. Aortic PWV was independently associated with LV ejection fraction (ss= -0.406, P = 0.006), LV stroke volume (ss=-0.407, P = 0.001), LV cardiac output (ss= -0.458, P = 0.001), and with cerebral WMHs (P < 0.05). There were no independent associations between aortic stiffness and LV mass, cerebral microbleeds or lacunar infarcts. Aortic stiffness is independently associated with systolic LV function and cerebral WMHs in patients with type 1 DM. (orig.)

  11. Relation of osteoprotegerin in severe aortic valve stenosis to postoperative outcome and left ventricular function

    DEFF Research Database (Denmark)

    Dahl, Jordi S; Videbæk, Lars; Poulsen, Mikael K

    2013-01-01

    ventricular (LV) function and remodeling and to evaluate the significance of preoperative OPG on long-term outcome in terms of survival and symptomatic improvement in 124 patients with severe AS scheduled for aortic valve replacement (AVR). Patients were divided according to tertiles of preoperative OPG......, 41 patients died of a presumed cardiovascular cause or remained in New York Heart Association functional class III or IV. The risk of a poor postoperative outcome after AVR increased with increasing OPG tertiles (15% vs 33% vs 51%, p = 0.002). In a multivariate model containing age, ejection fraction......, N-terminal pro-brain natriuretic peptide and left atrial volume index, OPG was still significantly associated with postoperative outcome. In addition, OPG levels associated with cardiovascular mortality during follow-up. In conclusion, OPG is associated with LV and left atrial remodeling in patients...

  12. Aortic dissection

    Science.gov (United States)

    ... linked to aortic dissection include: Bicuspid aortic valve Coarctation (narrowing) of the aorta Connective tissue disorders (such ... failure Aneurysm Aortic insufficiency Blood clots Cardiac tamponade Coarctation of the aorta Hardening of the arteries High ...

  13. Quantitative assessment of systolic left ventricular function with speckle-tracking echocardiography in adult patients with repaired aortic coarctation

    NARCIS (Netherlands)

    M.E. Menting (Myrthe); R.W.J. van Grootel (Roderick W. J.); A.E. van den Bosch (Annemien); J.A. Eindhoven (Jannet); J.S. McGhie (Jackie); J.A.A.E. Cuypers (Judith); M. Witsenburg (Maarten); W.A. Helbing (Willem); J.W. Roos-Hesselink (Jolien)

    2016-01-01

    textabstractDespite successful aortic coarctation (CoA) repair, systemic hypertension often recurs which may influence left ventricular (LV) function. We aimed to detect early LV dysfunction using LV global longitudinal strain (GLS) in adults with repaired CoA, and to identify associations with pati

  14. A linear functional differential equation with distributions in the input

    Directory of Open Access Journals (Sweden)

    Vadim Z. Tsalyuk

    2003-10-01

    Full Text Available This paper studies the functional differential equation $$ dot x(t = int_a^t {d_s R(t,s, x(s} + F'(t, quad t in [a,b], $$ where $F'$ is a generalized derivative, and $R(t,cdot$ and $F$ are functions of bounded variation. A solution is defined by the difference $x - F$ being absolutely continuous and satisfying the inclusion $$ frac{d}{dt} (x(t - F(t in int_a^t {d_s R(t,s,x(s}. $$ Here, the integral in the right is the multivalued Stieltjes integral presented in cite{VTs1} (in this article we review and extend the results in cite{VTs1}. We show that the solution set for the initial-value problem is nonempty, compact, and convex. A solution $x$ is said to have memory if there exists the function $x$ such that $x(a = x(a$, $x(b = x(b$, $ x(t in [x(t-0,x(t+0]$ for $t in (a,b$, and $frac{d}{dt} (x(t - F(t = int_a^t {d_s R(t,s,{x}(s}$, where Lebesgue-Stieltjes integral is used. We show that such solutions form a nonempty, compact, and convex set. It is shown that solutions with memory obey the Cauchy-type formula $$ x(t in C(t,ax(a + int_a^t C(t,s, dF(s. $$

  15. [Left ventricular function in hypertension without left ventricular hypertrophy: echographic study with modelisation of left ventricular-aortic coupling].

    Science.gov (United States)

    Bonnet, B; Jourdan, F; du Cailar, G; Mimran, A; Fesler, P

    2014-06-01

    Because the functional interaction between the LV and arterial systems, termed ventricular-arterial coupling, is recognized as a key determinant of LV performance, the objective of the present study was to assess the impact of uncomplicated HT without LVH on LV performance using simultaneously echocardiography and carotid tonometry. LV maximal power (PmaxVG), cardiac power output (CPO), LV efficiency (CPO/PmaxVG), input aortic and output LV elastance (Ea and Ees) were assessed in 20 normotensive control subjects (NT) and 10 patients with untreated HT. PmaxVG was calculated according to the integral of the product of LV wall stress with strain rate (as an index of gradient velocity). Cyclic variation of wall thickness and SR were measured by speckel-tracking. Ea and Ees were derived and modelized from the pressure-volume curve. No difference in age, BMI and sex ratio was observed between NT and HT. Systolic BP (160±18 vs. 119±10mmHg), LV mass (99±15 vs. 76±12g/m(2)), PWV (9.7±2 vs. 6.9±1m/s) were significantly higher (P<0.01) in HT when compared to NT. In HT increased of CPO and Ea was compensated by an increase of LV (15±4 vs. 12±3%, P<0.02) and Ees (5.5±2 vs. 4.5±1.5mmHg/mL), which are significantly elevated in HT (P<0.05). No difference was observed in Ea/Ees between NT and HT. In conclusion at the early phase of HT, in patients without LVH, LV performance and ventricular-arterial coupling were adapted to post-load elevation. This adaptation may be the result of an increased of LV contractility.

  16. Left atrial size and function as predictors of new-onset of atrial fibrillation in patients with asymptomatic aortic stenosis

    DEFF Research Database (Denmark)

    Bang, Casper N; Dalsgaard, Morten; Greve, Anders M

    2013-01-01

    BACKGROUND: Left atrial (LA) size and function change with chronically increased left ventricular (LV) filling pressures. It remains unclear whether these variations in LA parameters can predict new-onset atrial fibrillation (AF) in asymptomatic patients with aortic stenosis (AS). METHODS: Data...... were obtained in asymptomatic patients with mild-to-moderate AS (2.5≤ transaortic Doppler velocity ≤4.0m/s), preserved LV ejection fraction (EF), no previous AF, and were enrolled in the Simvastatin and Ezetimibe in Aortic Stenosis study. Peak-aortic velocity, LA(max) volume & LA(min) volume were...... age was 66±9.7years, aortic valve area index 0.6±0.2cm(2)/m(2), LV mass 99.2±29.7g/m(2), LA(max) volume 34.6±12.0mL/m(2), LA(min) volume 17.9±9.3mL/m(2), LA-EF 50±15% and LA(con) volume 45±21mL/m(2). Baseline LA(min) volume predicted new-onset AF in Cox multivariable analysis (HR:2.3 [95%CI:1...

  17. Aortic depressor nerve function examined in diabetic rats by means of two different approaches.

    Science.gov (United States)

    do Carmo, Jussara M; Huber, Domitila A; Castania, Jaci A; Fazan, Valéria P S; Fazan, Rubens; Salgado, Helio C

    2007-03-30

    The present study examined in anesthetized rats, 5 or 120 days after the onset of streptozotocin-induced diabetes, the aortic depressor nerve (ADN) function by means of pressure-nerve activity curve (fitted by sigmoidal regression) and cross-spectral analysis between mean arterial pressure (MAP) and ADN activity. From the sigmoidal regression curve it was calculated the upper and lower ADN activity plateau, range, average gain and MAP halfway between the lower and upper plateau (MAP50). By means of spectral analysis it was calculated the transfer function magnitude (ratio of ADN activity/MAP) as an index of ADN sensitivity (gain) during induced (withdrawal and reinfusion of blood) slow (0.35 Hz) oscillations of MAP simulating Mayer's waves and spontaneous oscillations (approximately 1.5 Hz) caused by respiratory movement. Diabetic rats exhibited, at 5 or 120 days, lower MAP and heart rate. The parameters calculated by means of the sigmoidal regression curve, as well as the ADN activity gain during slow or spontaneous oscillations of MAP, were similar in diabetic and control rats. In conclusion, it was demonstrated that ADN activity was not altered after 5 or 120 days of experimental diabetes, even though the literature documents, at this time frame of diabetes, a conspicuous derangement of the baroreflex.

  18. Effects of preemptive enoximone on left ventricular diastolic function after valve replacement for aortic stenosis

    NARCIS (Netherlands)

    van der Maaten, Joost M. A. A.; de Vries, Adrianus J.; Rietman, Gerrit W.; Gallandat Huet, Rolf C. G.; De Hert, Stefan G.

    2007-01-01

    Objective: Left ventricular (LV) hypertrophy is associated with increased diastolic chamber stiffness early after aortic valve replacement for valve stenosis. Enoximone, a phosphodiesterase III inhibitor, has been shown to improve myocardial contractility and relaxation when administered as a single

  19. SOD1 Overexpression Preserves Baroreflex Control of Heart Rate with an Increase of Aortic Depressor Nerve Function

    Science.gov (United States)

    Hatcher, Jeffrey; Gu, He; Cheng, Zixi (Jack)

    2016-01-01

    Overproduction of reactive oxygen species (ROS), such as the superoxide radical (O2∙−), is associated with diseases which compromise cardiac autonomic function. Overexpression of SOD1 may offer protection against ROS damage to the cardiac autonomic nervous system, but reductions of O2∙− may interfere with normal cellular functions. We have selected the C57B6SJL-Tg (SOD1)2 Gur/J mouse as a model to determine whether SOD1 overexpression alters cardiac autonomic function, as measured by baroreflex sensitivity (BRS) and aortic depressor nerve (ADN) recordings, as well as evaluation of baseline heart rate (HR) and mean arterial pressure (MAP). Under isoflurane anesthesia, C57 wild-type and SOD1 mice were catheterized with an arterial pressure transducer and measurements of HR and MAP were taken. After establishing a baseline, hypotension and hypertension were induced by injection of sodium nitroprusside (SNP) and phenylephrine (PE), respectively, and ΔHR versus ΔMAP were recorded as a measure of baroreflex sensitivity (BRS). SNP and PE treatment were administered sequentially after a recovery period to measure arterial baroreceptor activation by recording aortic depressor nerve activity. Our findings show that overexpression of SOD1 in C57B6SJL-Tg (SOD1)2 Gur/J mouse preserved the normal HR, MAP, and BRS but enhanced aortic depressor nerve function. PMID:26823951

  20. Effect of transverse aortic constriction on cardiac structure, function and gene expression in pregnant rats.

    Directory of Open Access Journals (Sweden)

    Nils Thomas Songstad

    Full Text Available BACKGROUND: There is an increased risk of heart failure and pulmonary edema in pregnancies complicated by hypertensive disorders. However, in a previous study we found that pregnancy protects against fibrosis and preserves angiogenesis in a rat model of angiotensin II induced cardiac hypertrophy. In this study we test the hypothesis that pregnancy protects against negative effects of increased afterload. METHODS: Pregnant (gestational day 5.5-8.5 and non-pregnant Wistar rats were randomized to transverse aortic constriction (TAC or sham surgery. After 14.2 ± 0.14 days echocardiography was performed. Aortic blood pressure and left ventricular (LV pressure-volume loops were obtained using a conductance catheter. LV collagen content and cardiomyocyte circumference were measured. Myocardial gene expression was assessed by real-time polymerase chain reaction. RESULTS: Heart weight was increased by TAC (p<0.001 but not by pregnancy. Cardiac myocyte circumference was larger in pregnant compared to non-pregnant rats independent of TAC (p = 0.01, however TAC per se did not affect this parameter. Collagen content in LV myocardium was not affected by pregnancy or TAC. TAC increased stroke work more in pregnant rats (34.1 ± 2.4 vs 17.5 ± 2.4 mmHg/mL, p<0.001 than in non-pregnant (28.2 ± 1.7 vs 20.9 ± 1.5 mmHg/mL, p = 0.06. However, it did not lead to overt heart failure in any group. In pregnant rats, α-MHC gene expression was reduced by TAC. Increased in the expression of β-MHC gene was higher in pregnant (5-fold compared to non-pregnant rats (2-fold after TAC (p = 0.001. Nine out of the 19 genes related to cardiac remodeling were affected by pregnancy independent of TAC. CONCLUSIONS: This study did not support the hypothesis that pregnancy is cardioprotective against the negative effects of increased afterload. Some differences in cardiac structure, function and gene expression between pregnant and non-pregnant rats following TAC indicated that

  1. Functional localization of neurotransmitter receptors and synaptic inputs to mature neurons of the medial superior olive.

    Science.gov (United States)

    Couchman, Kiri; Grothe, Benedikt; Felmy, Felix

    2012-02-01

    Neurons of the medial superior olive (MSO) code for the azimuthal location of low-frequency sound sources via a binaural coincidence detection system operating on microsecond time scales. These neurons are morphologically simple and stereotyped, and anatomical studies have indicated a functional segregation of excitatory and inhibitory inputs between cellular compartments. It is thought that this morphological arrangement holds important implications for the computational task of these cells. To date, however, there has been no functional investigation into synaptic input sites or functional receptor distributions on mature neurons of the MSO. Here, functional neurotransmitter receptor maps for amino-3-hydroxyl-5-methyl-4-isoxazole propionate (AMPA), N-methyl-D-aspartate (NMDA), glycine (Gly), and ionotropic γ-aminobutyric acid (GABA(A)) receptors (Rs) were compared and complemented by their corresponding synaptic input map. We find in MSO neurons from postnatal day 20-35 gerbils that AMPARs and their excitatory inputs target the soma and dendrites. Functional GlyRs and their inhibitory inputs are predominantly refined to the somata, although a pool of functional GlyRs is present extrasynaptically on MSO dendrites. GABA(A)R responses are present throughout the cell but lack direct synaptic contact indicating an involvement in volume transmission. NMDARs are present both synaptically and extrasynaptically with an overall distribution similar to GlyRs. Interestingly, even at physiological temperatures these functional NMDARs can be potentiated by synaptically released Gly. The functional receptor and synaptic input maps produced here led to the identification of a cross talk between transmitter systems and raises the possibility that extrasynaptic receptors could be modulating leak conductances as a homeostatic mechanism.

  2. Loss of function mutation in LOX causes thoracic aortic aneurysm and dissection in humans.

    Science.gov (United States)

    Lee, Vivian S; Halabi, Carmen M; Hoffman, Erin P; Carmichael, Nikkola; Leshchiner, Ignaty; Lian, Christine G; Bierhals, Andrew J; Vuzman, Dana; Mecham, Robert P; Frank, Natasha Y; Stitziel, Nathan O

    2016-08-01

    Thoracic aortic aneurysms and dissections (TAAD) represent a substantial cause of morbidity and mortality worldwide. Many individuals presenting with an inherited form of TAAD do not have causal mutations in the set of genes known to underlie disease. Using whole-genome sequencing in two first cousins with TAAD, we identified a missense mutation in the lysyl oxidase (LOX) gene (c.893T > G encoding p.Met298Arg) that cosegregated with disease in the family. Using clustered regularly interspaced short palindromic repeats (CRISPR)/clustered regularly interspaced short palindromic repeats-associated protein-9 nuclease (Cas9) genome engineering tools, we introduced the human mutation into the homologous position in the mouse genome, creating mice that were heterozygous and homozygous for the human allele. Mutant mice that were heterozygous for the human allele displayed disorganized ultrastructural properties of the aortic wall characterized by fragmented elastic lamellae, whereas mice homozygous for the human allele died shortly after parturition from ascending aortic aneurysm and spontaneous hemorrhage. These data suggest that a missense mutation in LOX is associated with aortic disease in humans, likely through insufficient cross-linking of elastin and collagen in the aortic wall. Mutation carriers may be predisposed to vascular diseases because of weakened vessel walls under stress conditions. LOX sequencing for clinical TAAD may identify additional mutation carriers in the future. Additional studies using our mouse model of LOX-associated TAAD have the potential to clarify the mechanism of disease and identify novel therapeutics specific to this genetic cause.

  3. Inhospital and Post-discharge Changes in Renal Function After Transcatheter Aortic Valve Replacement.

    Science.gov (United States)

    Blair, John E A; Brummel, Kent; Friedman, Julie L; Atri, Prashant; Sweis, Ranya N; Russell, Hyde; Ricciardi, Mark J; Malaisrie, S Chris; Davidson, Charles J; Flaherty, James D

    2016-02-15

    The aim of this study was to determine the influence of inhospital and post-discharge worsening renal function (WRF) on prognosis after transcatheter aortic valve replacement (TAVR). Severe chronic kidney disease and inhospital WRF are both associated with poor outcomes after TAVR. There are no data available on post-discharge WRF and outcomes. This was a single-center study evaluating all TAVR from June 1, 2008, to June 31, 2014. WRF was defined as an increase in serum creatinine of ≥0.3 mg/dl. Inhospital WRF was measured from day 0 until discharge or day 7 if the hospitalization was >7 days. Post-discharge WRF was measured at 30 days after discharge. Descriptive statistics, Kaplan-Meier time-to-event analysis, and multivariate logistic regression were used. In a series of 208 patients who underwent TAVR, 204 with complete renal function data were used in the inhospital analysis and 168 who returned for the 30-day follow-up were used in the post-discharge analysis. Inhospital WRF was seen in 28%, whereas post-discharge WRF in 12%. Inhospital and post-discharge WRF were associated with lower rates of survival; however, after multivariate analysis, only post-discharge WRF remained a predictor of 1-year mortality (hazard ratio 1.18, p = 0.030 for every 1 mg/dl increase in serum creatinine). In conclusion, the rate of inhospital WRF is higher than the rate of post-discharge WRF after TAVR, and post-discharge WRF is more predictive of mortality than inhospital WRF.

  4. TGFB2 loss of function mutations cause familial thoracic aortic aneurysms and acute aortic dissections associated with mild systemic features of the Marfan syndrome

    Science.gov (United States)

    Boileau, Catherine; Guo, Dong-Chuan; Hanna, Nadine; Regalado, Ellen S.; Detaint, Delphine; Gong, Limin; Varret, Mathilde; Prakash, Siddharth; Li, Alexander H.; d’Indy, Hyacintha; Braverman, Alan C.; Grandchamp, Bernard; Kwartler, Callie S.; Gouya, Laurent; Santos-Cortez, Regie Lyn P.; Abifadel, Marianne; Leal, Suzanne M.; Muti, Christine; Shendure, Jay; Gross, Marie-Sylvie; Rieder, Mark J.; Vahanian, Alec; Nickerson, Deborah A.; Michel, Jean Baptiste; Jondeau, Guillaume; Milewicz, Dianna M.

    2014-01-01

    A predisposition for thoracic aortic aneurysms leading to acute aortic dissections can be inherited in families in an autosomal dominant manner. Genome-wide linkage analysis of two large unrelated families with thoracic aortic disease, followed by whole exome sequencing of affected relatives, identified causative mutations in TGFB2. These mutations, a frameshift mutation in exon 6 and a nonsense mutation in exon 4, segregated with disease with a combined LOD score of 7.7. Sanger sequencing of 276 probands from families with inherited thoracic aortic disease identified two additional TGFB2 mutations. TGFB2 encodes the transforming growth factor beta-2 (TGF-β2) and the mutations are predicted to cause haploinsufficiency for TGFB2, but aortic tissue from cases paradoxically shows increased TGF-β2 expression and immunostaining. Thus, haploinsufficiency of TGFB2 predisposes to thoracic aortic disease, suggesting the initial pathway driving disease is decreased cellular TGF-β2 levels leading to a secondary increase in TGF-β2 production in the diseased aorta. PMID:22772371

  5. Prevalence, pattern, and functional impact of late gadolinium enhancement in left ventricular hypertrophy due to aortic valve stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Nassenstein, K.; Schlosser, T. [Universitaetsklinikum Essen (Germany). Abt. fuer Diagnostische und Interventionelle Radiologie; Bruder, O. [Elisabeth-Krankenhaus Essen (Germany). Klinik fuer Kardiologie und Angiologie; Breuckmann, F.; Erbel, R. [Universitaetsklinikum Essen (Germany). Westdeutsches Herzzentrum Essen; Barkhausen, J. [Universitaetsklinikum Schleswig-Holstein, Luebeck (Germany). Klinik fuer Radiologie und Nuklearmedizin

    2009-05-15

    Purpose: To assess the prevalence and pattern of myocardial late gadolinium enhancement (LGE) and its functional impact on patients with left ventricular hypertrophy caused by aortic valve stenosis. Materials and Methods: Cardiac magnetic resonance imaging of 40 patients (17 female, 23 male, mean age: 76.6 {+-} 22.5 years) with known aortic valve stenosis (mean aortic valve area: 89.8 {+-} 19.2 mm{sup 2}) and without coronary artery disease was performed at 1.5 T using steady-state free precession sequences for aortic valve planimetry and for the assessment of left ventricular (LV) volumes and mass. Ten to 15 minutes after injection of 0.2 mmol Gd-DTPA per kilogram body weight, inversion-recovery prepared spoiled gradient echo images were acquired in standard long and short axis views to detect areas of LGE. Results: LGE was observed in 32.5 % (13/40) of our patients. LGE was mainly located in the basal septal and inferior LV segments, and showed a non-ischemic pattern with sparing of the subendocardial region. Patients with LGE showed lower LV ejection fractions (55.5 {+-} 13.8 % vs. 69.1 {+-} 10.7 %, p = 0.0014), higher LV end-systolic volumes (59.8 {+-} 33.3 ml vs. 36.6 {+-} 16.0 ml, p = 0.0048), and LV masses (211.0 {+-} 13.8 vs. 157.9 {+-} 37.5 g, p = 0.0002) compared to patients without LGE. (orig.)

  6. PCSK9 R46L Loss-of-Function Mutation Reduces Lipoprotein(a), LDL Cholesterol, and Risk of Aortic Valve Stenosis

    DEFF Research Database (Denmark)

    Langsted, Anne; Nordestgaard, Børge G; Benn, Marianne;

    2016-01-01

    CONTEXT: Novel, low-density lipoprotein (LDL) cholesterol-lowering proprotein convertase subtilisin/kexin type-9 (PCSK9) inhibitors also lower lipoprotein(a) levels, but the effect on aortic valve stenosis and myocardial infarction is unknown. OBJECTIVE: We tested the hypothesis that the PCSK9 R46L...... loss-of-function mutation is associated with lower levels of lipoprotein(a) and with reduced risk of aortic valve stenosis and myocardial infarction. DESIGN: We used two prospective cohort studies of the general population and one patient-based cohort. SETTING: Cohort studies selected at random...... valve stenosis, 0.77 (0.65-0.92) for myocardial infarction, and 0.76 (0.64-0.89) for aortic valve stenosis or myocardial infarction. CONCLUSIONS: PCSK9 R46L carriers have lower levels of lipoprotein(a) and LDL cholesterol as well as reduced risk of aortic valve stenosis and myocardial infarction...

  7. Reconstruction of an input function from a dynamic PET water image using multiple tissue curves

    Science.gov (United States)

    Kudomi, Nobuyuki; Maeda, Yukito; Yamamoto, Yuka; Nishiyama, Yoshihiro

    2016-08-01

    Quantification of cerebral blood flow (CBF) is important for the understanding of normal and pathologic brain physiology. When CBF is assessed using PET with {{\\text{H}}2} 15O or C15O2, its calculation requires an arterial input function, which generally requires invasive arterial blood sampling. The aim of the present study was to develop a new technique to reconstruct an image derived input function (IDIF) from a dynamic {{\\text{H}}2} 15O PET image as a completely non-invasive approach. Our technique consisted of using a formula to express the input using tissue curve with rate constant parameter. For multiple tissue curves extracted from the dynamic image, the rate constants were estimated so as to minimize the sum of the differences of the reproduced inputs expressed by the extracted tissue curves. The estimated rates were used to express the inputs and the mean of the estimated inputs was used as an IDIF. The method was tested in human subjects (n  =  29) and was compared to the blood sampling method. Simulation studies were performed to examine the magnitude of potential biases in CBF and to optimize the number of multiple tissue curves used for the input reconstruction. In the PET study, the estimated IDIFs were well reproduced against the measured ones. The difference between the calculated CBF values obtained using the two methods was small as around  <8% and the calculated CBF values showed a tight correlation (r  =  0.97). The simulation showed that errors associated with the assumed parameters were  <10%, and that the optimal number of tissue curves to be used was around 500. Our results demonstrate that IDIF can be reconstructed directly from tissue curves obtained through {{\\text{H}}2} 15O PET imaging. This suggests the possibility of using a completely non-invasive technique to assess CBF in patho-physiological studies.

  8. Correcting partial volume artifacts of the arterial input function in quantitative cerebral perfusion MRI

    NARCIS (Netherlands)

    van Osch, MJP; Vonken, EJPA; Bakker, CJG; Viergever, MA

    2001-01-01

    To quantify cerebral perfusion with dynamic susceptibility contrast MRI (DSC-MRI), one needs to measure the arterial input function (AIF). Conventionally, one derives the contrast concentration from the DSC sequence by monitoring changes in either the amplitude or the phase signal on the assumption

  9. Aortic and Cardiac Structure and Function Using High-Resolution Echocardiography and Optical Coherence Tomography in a Mouse Model of Marfan Syndrome

    Science.gov (United States)

    Lee, Ling; Cui, Jason Z.; Cua, Michelle; Esfandiarei, Mitra; Sheng, Xiaoye; Chui, Winsey Audrey; Xu, Michael Haoying; Sarunic, Marinko V.; Beg, Mirza Faisal; van Breemen, Cornelius; Sandor, George G. S.

    2016-01-01

    Marfan syndrome (MFS) is an autosomal-dominant disorder of connective tissue caused by mutations in the fibrillin-1 (FBN1) gene. Mortality is often due to aortic dissection and rupture. We investigated the structural and functional properties of the heart and aorta in a [Fbn1C1039G/+] MFS mouse using high-resolution ultrasound (echo) and optical coherence tomography (OCT). Echo was performed on 6- and 12-month old wild type (WT) and MFS mice (n = 8). In vivo pulse wave velocity (PWV), aortic root diameter, ejection fraction, stroke volume, left ventricular (LV) wall thickness, LV mass and mitral valve early and atrial velocities (E/A) ratio were measured by high resolution echocardiography. OCT was performed on 12-month old WT and MFS fixed mouse hearts to measure ventricular volume and mass. The PWV was significantly increased in 6-mo MFS vs. WT (366.6 ± 19.9 vs. 205.2 ± 18.1 cm/s; p = 0.003) and 12-mo MFS vs. WT (459.5 ± 42.3 vs. 205.3 ± 30.3 cm/s; pMarfan patients including significant aortic dilation, central aortic stiffness, LV systolic and diastolic dysfunction. This is the first demonstration of the direct measurement in vivo of pulse wave velocity non-invasively in the aortic arch of MFS mice, a robust measure of aortic stiffness and a critical clinical parameter for the assessment of pathology in the Marfan syndrome. PMID:27824871

  10. Surgery for severe aortic stenosis with low transvalvular gradient and poor left ventricular function – a single centre experience and review of the literature

    Directory of Open Access Journals (Sweden)

    Vchivkov Ilja

    2007-01-01

    Full Text Available Abstract Background A retrospective comparative study was designed to determine whether the transvalvular gradient has a predictive value in the assessment of operative outcome in patients with severe aortic stenosis and poor left ventricular function. Methods From a surgical database, a series of 30 consecutive patients, who underwent isolated aortic valve replacement for severe aortic stenosis with depressed left ventricular (LV function (EF 40 mmHg (n = 17. Both groups were then comparatively assessed with respect to perioperative organ functions and mortality. Results Both groups were well matched with respect to the preoperative clinical status. LG-Group had a larger aortic valve area, higher LVEDP, larger LVESD and LVEDD, and higher mean pulmonary pressures. The immediate postoperative outcome, hospital morbidity and mortality did not differ significantly among the groups. Conclusion In patients with severe aortic stenosis and poor LV function, the mean transvalvular gradient, although corresponds to reduced LV performance, has a limited prognostic value in the assessment of surgical outcome. Generally, operating on this select group of patients is safe.

  11. Effects of Ground Motion Input on the Derived Fragility Functions: Case study of 2010 Haiti Earthquake

    Science.gov (United States)

    Hancilar, Ufuk; Harmandar, Ebru; Çakti, Eser

    2014-05-01

    Empirical fragility functions are derived by statistical processing of the data on: i) Damaged and undamaged buildings, and ii) Ground motion intensity values at the buildings' locations. This study investigates effects of different ground motion inputs on the derived fragility functions. The previously constructed fragility curves (Hancilar et al. 2013), which rely on specific shaking intensity maps published by the USGS after the 2010 Haiti Earthquake, are compared with the fragility functions computed in the present study. Building data come from field surveys of 6,347 buildings that are grouped with respect to structural material type and number of stories. For damage assessment, the European Macroseismic Scale (EMS-98) damage grades are adopted. The simplest way to account for the variability in ground motion input could have been achieved by employing different ground motion prediction equations (GMPEs) and their standard variations. However, in this work, we prefer to rely on stochastically simulated ground motions of the Haiti earthquake. We employ five different source models available in the literature and calculate the resulting strong ground motion in time domain. In our simulations we also consider the local site effects by published studies on NEHRP site classes and micro-zoning maps of the city of Port-au-Prince. We estimate the regional distributions from the waveforms simulated at the same coordinates that we have damage information from. The estimated spatial distributions of peak ground accelerations and velocities, PGA and PGV respectively, are then used as input to fragility computations. The results show that changing the ground motion input causes significant variability in the resulting fragility functions.

  12. Characteristic operator functions for quantum input-plant-output models and coherent control

    Science.gov (United States)

    Gough, John E.

    2015-01-01

    We introduce the characteristic operator as the generalization of the usual concept of a transfer function of linear input-plant-output systems to arbitrary quantum nonlinear Markovian input-output models. This is intended as a tool in the characterization of quantum feedback control systems that fits in with the general theory of networks. The definition exploits the linearity of noise differentials in both the plant Heisenberg equations of motion and the differential form of the input-output relations. Mathematically, the characteristic operator is a matrix of dimension equal to the number of outputs times the number of inputs (which must coincide), but with entries that are operators of the plant system. In this sense, the characteristic operator retains details of the effective plant dynamical structure and is an essentially quantum object. We illustrate the relevance to model reduction and simplification definition by showing that the convergence of the characteristic operator in adiabatic elimination limit models requires the same conditions and assumptions appearing in the work on limit quantum stochastic differential theorems of Bouten and Silberfarb [Commun. Math. Phys. 283, 491-505 (2008)]. This approach also shows in a natural way that the limit coefficients of the quantum stochastic differential equations in adiabatic elimination problems arise algebraically as Schur complements and amounts to a model reduction where the fast degrees of freedom are decoupled from the slow ones and eliminated.

  13. Improved hepatic arterial fraction estimation using cardiac output correction of arterial input functions for liver DCE MRI

    Science.gov (United States)

    Chouhan, Manil D.; Bainbridge, Alan; Atkinson, David; Punwani, Shonit; Mookerjee, Rajeshwar P.; Lythgoe, Mark F.; Taylor, Stuart A.

    2017-02-01

    Liver dynamic contrast enhanced (DCE) MRI pharmacokinetic modelling could be useful in the assessment of diffuse liver disease and focal liver lesions, but is compromised by errors in arterial input function (AIF) sampling. In this study, we apply cardiac output correction to arterial input functions (AIFs) for liver DCE MRI and investigate the effect on dual-input single compartment hepatic perfusion parameter estimation and reproducibility. Thirteen healthy volunteers (28.7  ±  1.94 years, seven males) underwent liver DCE MRI and cardiac output measurement using aortic root phase contrast MRI (PCMRI), with reproducibility (n  =  9) measured at 7 d. Cardiac output AIF correction was undertaken by constraining the first pass AIF enhancement curve using the indicator-dilution principle. Hepatic perfusion parameters with and without cardiac output AIF correction were compared and 7 d reproducibility assessed. Differences between cardiac output corrected and uncorrected liver DCE MRI portal venous (PV) perfusion (p  =  0.066), total liver blood flow (TLBF) (p  =  0.101), hepatic arterial (HA) fraction (p  =  0.895), mean transit time (MTT) (p  =  0.646), distribution volume (DV) (p  =  0.890) were not significantly different. Seven day corrected HA fraction reproducibility was improved (mean difference 0.3%, Bland–Altman 95% limits-of-agreement (BA95%LoA)  ±27.9%, coefficient of variation (CoV) 61.4% versus 9.3%, ±35.5%, 81.7% respectively without correction). Seven day uncorrected PV perfusion was also improved (mean difference 9.3 ml min‑1/100 g, BA95%LoA  ±506.1 ml min‑1/100 g, CoV 64.1% versus 0.9 ml min‑1/100 g, ±562.8 ml min‑1/100 g, 65.1% respectively with correction) as was uncorrected TLBF (mean difference 43.8 ml min‑1/100 g, BA95%LoA  ±586.7 ml min‑1/ 100 g, CoV 58.3% versus 13.3 ml min‑1/100 g, ±661.5 ml min‑1/100 g, 60

  14. Minimally invasive input function for 2-{sup 18}F-fluoro-A-85380 brain PET studies

    Energy Technology Data Exchange (ETDEWEB)

    Zanotti-Fregonara, Paolo [National Institute of Mental Health, NIH, Molecular Imaging Branch, Bethesda, MD (United States); Maroy, Renaud; Peyronneau, Marie-Anne; Trebossen, Regine [CEA, DSV, I2BM, Service Hospitalier Frederic Joliot, Orsay (France); Bottlaender, Michel [CEA, DSV, I2BM, NeuroSpin, Gif-sur-Yvette (France)

    2012-04-15

    Quantitative neuroreceptor positron emission tomography (PET) studies often require arterial cannulation to measure input function. While population-based input function (PBIF) would be a less invasive alternative, it has only rarely been used in conjunction with neuroreceptor PET tracers. The aims of this study were (1) to validate the use of PBIF for 2-{sup 18}F-fluoro-A-85380, a tracer for nicotinic receptors; (2) to compare the accuracy of measures obtained via PBIF to those obtained via blood-scaled image-derived input function (IDIF) from carotid arteries; and (3) to explore the possibility of using venous instead of arterial samples for both PBIF and IDIF. Ten healthy volunteers underwent a dynamic 2-{sup 18}F-fluoro-A-85380 brain PET scan with arterial and, in seven subjects, concurrent venous serial blood sampling. PBIF was obtained by averaging the normalized metabolite-corrected arterial input function and subsequently scaling each curve with individual blood samples. IDIF was obtained from the carotid arteries using a blood-scaling method. Estimated Logan distribution volume (V{sub T}) values were compared to the reference values obtained from arterial cannulation. For all subjects, PBIF curves scaled with arterial samples were similar in shape and magnitude to the reference arterial input function. The Logan V{sub T} ratio was 1.00 {+-} 0.05; all subjects had an estimation error <10%. IDIF gave slightly less accurate results (V{sub T} ratio 1.03 {+-} 0.07; eight of ten subjects had an error <10%). PBIF scaled with venous samples yielded inaccurate results (V{sub T} ratio 1.13 {+-} 0.13; only three of seven subjects had an error <10%). Due to arteriovenous differences at early time points, IDIF could not be calculated using venous samples. PBIF scaled with arterial samples accurately estimates Logan V{sub T} for 2-{sup 18}F-fluoro-A-85380. Results obtained with PBIF were slightly better than those obtained with IDIF. Due to arteriovenous concentration

  15. ASYMPTOTICAL STABILITY OFNON-AUTONOMOUS DISCRETE-TIME NEURAL NETWORKS WITH GENERALIZED INPUT-OUTPUT FUNCTION

    Institute of Scientific and Technical Information of China (English)

    阮炯; 王军平; 郭德典

    2004-01-01

    In this paper, we first introduce the model of discrete-time neural networks with generalized input-output function and present a proof of the existence of a fixed point by Schauder fixed-point principle. Secondly, we study the uniformly asymptotical stability of equilibrium in non-autonomous discrete-time neural networks and give some sufficient conditions that guarantee the stability of it by using the converse theorem of Lyapunov function. Finally, several examples and numerical simulations are given to illustrate and reinforce our theories.

  16. Mechanical analysis of functionally graded plates based on the input data of metallographic diagrams

    Institute of Scientific and Technical Information of China (English)

    CAO ZhiYuan; TANG ShouGao; CHENG HongMei

    2008-01-01

    A microelement method for scale-span analysis of material microstructure and member macro re-sponse has been proposed. Instead of material parameter input for traditional mechanical analysis, the method is based on the input of metallographic diagram information. In order to express the material microstructure, this method arranges concentrated microelements in ordinary finite element before calculation, and transfers the node degrees of freedom of each microelement into the ones of the same finite element via compatibility conditions. This method can realize direct transition analysis from ma-terial microstructure to macro responses of members, while computation elements and degrees of freedom are equal to those of ordinary FEM. Based on the complicated microstructure diagrams pro-posed by material metallographic diagram, the mechanics responses of functionally graded plates are calculated and 3-D distributions of macro-mechanical variables and identical stress lines tendency on microstructure are given.

  17. Basal longitudinal strain predicts future aortic valve replacement in asymptomatic patients with aortic stenosis

    DEFF Research Database (Denmark)

    Carstensen, Helle Gervig; Larsen, Linnea Hornbech; Hassager, Christian

    2016-01-01

    of myocardial dysfunction and predictors of outcome in asymptomatic aortic stenosis. Aortic stenosis and ischaemic heart disease share risk factors and longitudinal function can be severely reduced in both conditions, why some of the previous findings of impaired regional longitudinal function in asymptomatic...... aortic stenosis could in fact be explained by silent ischaemic heart disease. METHODS AND RESULTS: Prospective follow-up of 104 asymptomatic patients with moderate-severe aortic stenosis defined as an aortic valve area ...: In contrast to GLS, reduced BLS is a significant predictor of future AVR in asymptomatic patients with aortic stenosis, independently of clinical characteristics, conventional echocardiographic measures, and coronary pathology....

  18. Characterizing the Input-Output Function of the Olfactory-Limbic Pathway in the Guinea Pig

    Directory of Open Access Journals (Sweden)

    Gian Luca Breschi

    2015-01-01

    Full Text Available Nowadays the neuroscientific community is taking more and more advantage of the continuous interaction between engineers and computational neuroscientists in order to develop neuroprostheses aimed at replacing damaged brain areas with artificial devices. To this end, a technological effort is required to develop neural network models which can be fed with the recorded electrophysiological patterns to yield the correct brain stimulation to recover the desired functions. In this paper we present a machine learning approach to derive the input-output function of the olfactory-limbic pathway in the in vitro whole brain of guinea pig, less complex and more controllable than an in vivo system. We first experimentally characterized the neuronal pathway by delivering different sets of electrical stimuli from the lateral olfactory tract (LOT and by recording the corresponding responses in the lateral entorhinal cortex (l-ERC. As a second step, we used information theory to evaluate how much information output features carry about the input. Finally we used the acquired data to learn the LOT-l-ERC “I/O function,” by means of the kernel regularized least squares method, able to predict l-ERC responses on the basis of LOT stimulation features. Our modeling approach can be further exploited for brain prostheses applications.

  19. Characterizing the Input-Output Function of the Olfactory-Limbic Pathway in the Guinea Pig.

    Science.gov (United States)

    Breschi, Gian Luca; Ciliberto, Carlo; Nieus, Thierry; Rosasco, Lorenzo; Taverna, Stefano; Chiappalone, Michela; Pasquale, Valentina

    2015-01-01

    Nowadays the neuroscientific community is taking more and more advantage of the continuous interaction between engineers and computational neuroscientists in order to develop neuroprostheses aimed at replacing damaged brain areas with artificial devices. To this end, a technological effort is required to develop neural network models which can be fed with the recorded electrophysiological patterns to yield the correct brain stimulation to recover the desired functions. In this paper we present a machine learning approach to derive the input-output function of the olfactory-limbic pathway in the in vitro whole brain of guinea pig, less complex and more controllable than an in vivo system. We first experimentally characterized the neuronal pathway by delivering different sets of electrical stimuli from the lateral olfactory tract (LOT) and by recording the corresponding responses in the lateral entorhinal cortex (l-ERC). As a second step, we used information theory to evaluate how much information output features carry about the input. Finally we used the acquired data to learn the LOT-l-ERC "I/O function," by means of the kernel regularized least squares method, able to predict l-ERC responses on the basis of LOT stimulation features. Our modeling approach can be further exploited for brain prostheses applications.

  20. A time-resolved model of the mesospheric Na layer: constraints on the meteor input function

    Directory of Open Access Journals (Sweden)

    J. M. C. Plane

    2004-01-01

    Full Text Available A time-resolved model of the Na layer in the mesosphere/lower thermosphere region is described, where the continuity equations for the major sodium species Na, Na+ and NaHCO3 are solved explicity, and the other short-lived species are treated in steady-state. It is shown that the diurnal variation of the Na layer can only be modelled satisfactorily if sodium species are permanently removed below about 85 km, both through the dimerization of NaHCO3 and the uptake of sodium species on meteoric smoke particles that are assumed to have formed from the recondensation of vaporized meteoroids. When the sensitivity of the Na layer to the meteoroid input function is considered, an inconsistent picture emerges. The ratio of the column abundance of Na+ to Na is shown to increase strongly with the average meteoroid velocity, because the Na is injected at higher altitudes. Comparison with a limited set of Na+ measurements indicates that the average meteoroid velocity is probably less than about 25 km s-1, in agreement with velocity estimates from conventional meteor radars, and considerably slower than recent observations made by wide aperture incoherent scatter radars. The Na column abundance is shown to be very sensitive to the meteoroid mass input rate, and to the rate of vertical transport by eddy diffusion. Although the magnitude of the eddy diffusion coefficient in the 80–90 km region is uncertain, there is a consensus between recent models using parameterisations of gravity wave momentum deposition that the average value is less than 3×105 cm2 s-1. This requires that the global meteoric mass input rate is less than about 20 td-1, which is closest to estimates from incoherent scatter radar observations. Finally, the diurnal variation in the meteoroid input rate only slight perturbs the Na layer, because the residence time of Na in the layer is several days, and diurnal effects are effectively averaged out.

  1. Combining MRI with PET for partial volume correction improves image-derived input functions in mice

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Eleanor; Buonincontri, Guido [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Izquierdo, David [Athinoula A Martinos Centre, Harvard University, Cambridge, MA (United States); Methner, Carmen [Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Hawkes, Rob C [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Ansorge, Richard E [Department of Physics, University of Cambridge, Cambridge (United Kingdom); Kreig, Thomas [Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Carpenter, T Adrian [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Sawiak, Stephen J [Wolfson Brain Imaging Centre, University of Cambridge, Cambridge (United Kingdom); Behavioural and Clinical Neurosciences Institute, University of Cambridge, Cambridge (United Kingdom)

    2014-07-29

    Kinetic modelling in PET requires the arterial input function (AIF), defined as the time-activity curve (TAC) in plasma. This measure is challenging to obtain in mice due to low blood volumes, resulting in a reliance on image-based methods for AIF derivation. We present a comparison of PET- and MR-based region-of-interest (ROI) analysis to obtain image-derived AIFs from the left ventricle (LV) of a mouse model. ROI-based partial volume correction (PVC) was performed to improve quantification.

  2. Early Diastolic Strain Rate in Relation to Systolic and Diastolic Function and Prognosis in Aortic Stenosis

    DEFF Research Database (Denmark)

    Dahl, Jordi S; Barros-Gomes, Sergio; Videbæk, Lars

    2016-01-01

    OBJECTIVES: This study examined the impact of early mitral inflow velocity-to-early diastolic strain rate (E/SRe) ratio on long-term outcome after aortic valve replacement (AVR) in aortic stenosis (AS). BACKGROUND: In AS, increased filling pressures are associated with a poor prognosis and can...... Aortic Stenosis; NCT00294775)....... be estimated using the early diastolic mitral inflow velocity-to-early diastolic velocity of the mitral annulus (E/e') ratio. Recent studies suggest that the E/SRe ratio surpasses the E/e' ratio in estimating outcome. METHODS: Pre-operative evaluation was performed in 121 patients with severe AS (aortic valve...

  3. Aortic stenosis

    Science.gov (United States)

    ... Images Aortic stenosis Heart valves References Carabello BA. Valvular heart disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil ... ACC guideline for the management of patients with valvular heart disease: a report of the American College of Cardiology/ ...

  4. Abdominal Aortic Aneurysm (AAA)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Abdominal Aortic Aneurysm (AAA) Abdominal aortic aneurysm (AAA) occurs when atherosclerosis ... an abdominal aortic aneurysm treated? What is an abdominal aortic aneurysm? The aorta, the largest artery in the body, ...

  5. Left ventricular myocardial function in congenital valvar aortic stenosis assessed by ultrasound tissue-velocity and strain-rate techniques.

    NARCIS (Netherlands)

    Kiraly, P.; Kapusta, L.; Thijssen, J.M.; Daniëls, O.

    2003-01-01

    A pilot study was performed to reveal the potentials of new echo Doppler techniques for the detection of myocardial changes due to congenital valvar aortic stenosis. A total of 24 patients, (age range 0.1 to 17 years), with various degrees of aortic stenosis, and 24 age- and gender-matched, healthy

  6. Functional cardiac MRI for assessment of aortic valve disease; Aortenklappenstenose im MRT mit Dynamik und 3D

    Energy Technology Data Exchange (ETDEWEB)

    Sagmeister, F.; Ritter, C.; Machann, W.; Koestler, H.; Hahn, D.; Beer, M. [Universitaetsklinikum Wuerzburg, Institut fuer Roentgendiagnostik, Wuerzburg (Germany); Herrmann, S.; Voelker, W.; Weidemann, F. [Universitaetsklinikum Wuerzburg, Medizinische Klinik I, Wuerzburg (Germany)

    2010-06-15

    Aortic valve disease shows a rising incidence with the increasing mean age of Western populations. The detection of hemodynamic parameters, which transcends the mere assessment of valve morphology, has an important future potential concerning classification of the severity of disease. MRI allows a non-invasive and a spatially flexible view of the aortic valve and the adjacent anatomic region, left ventricular outflow tract (LVOT) and ascending aorta. Moreover, the technique allows the determination of functional hemodynamic parameters, such as flow velocities and effective orifice areas. The new approach of a serial systolic planimetry velocity-encoded MRI sequence (VENC-MRI) facilitates the sizing of blood-filled cardiac structures with the registration of changes in magnitude during systole. Additionally, the subvalvular VENC-MRI measurements improve the clinically important exact determination of the LVOT area with respect to its specific eccentric configuration and its systolic deformity. (orig.) [German] Erworbene Erkrankungen der Aortenklappe wie die Aortenklappenstenose zeigen mit zunehmender Alterungstendenz unserer Gesellschaft eine ansteigende Inzidenz. Die Erfassung ueber die reine Klappenmorphologie hinausgehender haemodynamischer Parameter hat ein wichtiges zukuenftiges Potenzial zur Schweregradeinschaetzung. Die MRT erlaubt eine nichtinvasive und raeumlich flexible Darstellung der Aortenklappe sowie ihrer benachbarten anatomischen Strukturen (linksventrikulaerer Ausflusstrakt/LVOT, Aorta ascendens). Darueber hinaus ist eine Bestimmung funktioneller haemodynamischer Parameter wie Flussgeschwindigkeiten und effektiven Oeffnungsflaechen (EOeF) moeglich. Der neue Ansatz einer seriellen Planimetrie geschwindigkeitskodierter MRT-Sequenzen (Velocity-encoding- [VENC-]MRT) erlaubt die Groessenbestimmung flussdurchstroemter kardialer Strukturen und die Aufzeichnung ihrer dynamischen Groessenveraenderung waehrend der Systole. Zusaetzlich ermoeglicht die

  7. Decellularized aortic conduits: could their cryopreservation affect post-implantation outcomes? A morpho-functional study on porcine homografts.

    Science.gov (United States)

    Gallo, Michele; Bonetti, Antonella; Poser, Helen; Naso, Filippo; Bottio, Tomaso; Bianco, Roberto; Paolin, Adolfo; Franci, Paolo; Busetto, Roberto; Frigo, Anna Chiara; Buratto, Edward; Spina, Michele; Marchini, Maurizio; Ortolani, Fulvia; Iop, Laura; Gerosa, Gino

    2016-11-01

    Decellularized porcine aortic valve conduits (AVCs) implanted in a Vietnamese Pig (VP) experimental animal model were matched against decellularized and then cryopreserved AVCs to assess the effect of cryopreservation on graft hemodynamic performance and propensity to in vivo repopulation by host's cells. VPs (n = 12) underwent right ventricular outflow tract substitution using AVC allografts and were studied for 15-month follow-up. VPs were randomized into two groups, receiving AVCs treated with decellularization alone (D; n = 6) or decellularization/cryopreservation (DC; n = 6), respectively. Serial echocardiography was carried out to follow up hemodynamic function. All explanted AVCs were processed for light and electron microscopy. No signs of dilatation, progressive stenosis, regurgitation, and macroscopic calcification were echocardiographically observed in both D and DC groups. Explanted D grafts exhibited near-normal features, whereas the presence of calcification, inflammatory infiltrates, and disarray of elastic lamellae occurred in some DC grafts. In the unaltered regions of AVCs from both groups, almost complete re-endothelialization was observed for both valve cusps and aorta walls. In addition, side-by-side repopulation by recipient's fibroblasts, myofibroblasts, and smooth muscle cells was paralleled by ongoing tissue remodeling, as revealed by the ultrastructural identification of typical canals of collagen fibrillogenesis and elastogenesis-related features. Incipient neo-vascularization and re-innervation of medial and adventitial tunicae of grafted aortic walls were also detected for both D and DC groups. Cryopreservation did not affect post-implantation AVC hemodynamic behavior and was topically propensive to cell repopulation and tissue renewal, although graft deterioration including calcification was present in several areas. Thus, these preliminary data provide essential information on feasibility of decellularization and

  8. Functional identification of the input-output transforms of mammalian motoneurones.

    Science.gov (United States)

    Binder, M D; Poliakov, A V; Powers, R K

    1999-01-01

    transform could be predicted from the mean firing rate and the linear impulse response, yielding a relatively simple, general description of the motoneurone's input-output function.

  9. Correction of an input function for errors introduced with automated blood sampling

    Energy Technology Data Exchange (ETDEWEB)

    Schlyer, D.J.; Dewey, S.L. [Brookhaven National Lab., Upton, NY (United States)

    1994-05-01

    Accurate kinetic modeling of PET data requires an precise arterial plasma input function. The use of automated blood sampling machines has greatly improved the accuracy but errors can be introduced by the dispersion of the radiotracer in the sampling tubing. This dispersion results from three effects. The first is the spreading of the radiotracer in the tube due to mass transfer. The second is due to the mechanical action of the peristaltic pump and can be determined experimentally from the width of a step function. The third is the adsorption of the radiotracer on the walls of the tubing during transport through the tube. This is a more insidious effect since the amount recovered from the end of the tube can be significantly different than that introduced into the tubing. We have measured the simple mass transport using [{sup 18}F]fluoride in water which we have shown to be quantitatively recovered with no interaction with the tubing walls. We have also carried out experiments with several radiotracers including [{sup 18}F]Haloperidol, [{sup 11}C]L-deprenyl, [{sup 18}]N-methylspiroperidol ([{sup 18}F]NMS) and [{sup 11}C]buprenorphine. In all cases there was some retention of the radiotracer by untreated silicone tubing. The amount retained in the tubing ranged from 6% for L-deprenyl to 30% for NMS. The retention of the radiotracer was essentially eliminated after pretreatment with the relevant unlabeled compound. For example less am 2% of the [{sup 18}F]NMS was retained in tubing treated with unlabelled NMS. Similar results were obtained with baboon plasma although the amount retained in the untreated tubing was less in all cases. From these results it is possible to apply a mathematical correction to the measured input function to account for mechanical dispersion and to apply a chemical passivation to the tubing to reduce the dispersion due to adsorption of the radiotracer on the tubing walls.

  10. Different vitamin D receptor agonists exhibit differential effects on endothelial function and aortic gene expression in 5/6 nephrectomized rats.

    Science.gov (United States)

    Wu-Wong, J Ruth; Li, Xinmin; Chen, Yung-Wu

    2015-04-01

    Endothelial dysfunction, common in chronic kidney disease (CKD), significantly increases cardiovascular disease risk in CKD patients. This study investigates whether different vitamin D receptor agonists exhibit different effects on endothelial function and on aortic gene expression in an animal CKD model. The 5/6 nephrectomized (NX) rat was treated with or without alfacalcidol (0.02, 0.04 and 0.08μg/kg), paricalcitol (0.04 and 0.08μg/kg), or VS-105 (0.004, 0.01 and 0.16μg/kg). All three compounds at the test doses suppressed serum parathyroid hormone effectively. Alfacalcidol at 0.08μg/kg raised serum calcium significantly. Endothelial function was assessed by pre-contracting thoracic aortic rings with phenylephrine, followed by treatment with acetylcholine or sodium nitroprusside. Uremia significantly affected endothelial-dependent aortic relaxation, which was improved by all three compounds in a dose-dependent manner with alfacalcidol and paricalcitol exhibiting a lesser effect. DNA microarray analysis of aorta samples revealed that uremia impacted the expression of numerous aortic genes, many of which were normalized by the vitamin D analogs. Real-time RT-PCR analysis confirmed that selected genes such as Abra, Apoa4, Fabp2, Hsd17b2, and Hspa1b affected by uremia were normalized by the vitamin D analogs with alfacalcidol exhibiting less of an effect. These results demonstrate that different vitamin D analogs exhibit different effects on endothelial function and aortic gene expression in 5/6 NX rats. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.

  11. Image derived input functions for dynamic High Resolution Research Tomograph PET brain studies.

    Science.gov (United States)

    Mourik, Jurgen E M; van Velden, Floris H P; Lubberink, Mark; Kloet, Reina W; van Berckel, Bart N M; Lammertsma, Adriaan A; Boellaard, Ronald

    2008-12-01

    The High Resolution Research Tomograph (HRRT) is a dedicated human brain positron emission tomography (PET) scanner. The aim of the present study was to validate the use of image derived input functions (IDIF) as an alternative for arterial sampling for HRRT human brain studies. To this end, IDIFs were extracted from 3D ordinary Poisson ordered subsets expectation maximization (OP-OSEM) and reconstruction based partial volume corrected (PVC) OP-OSEM images. IDIFs, either derived directly from regions of interest or further calibrated using manual samples taken during scans, were evaluated for dynamic [(11)C]flumazenil data (n=6). Results obtained with IDIFs were compared with those obtained using blood sampler input functions (BSIF). These comparisons included areas under the curve (AUC) for peak (0-3.3 min) and tail (3.3-55.0 min). In addition, slope, intercept and Pearson's correlation coefficient of tracer kinetic analysis results based on IDIF and BSIF were calculated for each subject. Good peak AUC ratios (0.83+/-0.21) between IDIF and BSIF were found for calibrated IDIFs extracted from OP-OSEM images. This combination of IDIFs and images also provided good slope values (1.07+/-0.11). Improved resolution, as obtained with PVC OP-OSEM, changed AUC ratios to 1.14+/-0.35 and, for tracer kinetic analysis, slopes changed to 0.95+/-0.13. For all reconstructions, non-calibrated IDIFs gave poorer results (>61+/-34% higher slopes) compared with calibrated IDIFs. The results of this study indicate that the use of IDIFs, extracted from OP-OSEM or PVC OP-OSEM images, is feasible for dynamic HRRT data, thereby obviating the need for online arterial sampling.

  12. Comparison of Parameter Estimations Using Dual-Input and Arterial-Input in Liver Kinetic Studies of FDG Metabolism.

    Science.gov (United States)

    Cui, Yunfeng; Bai, Jing

    2005-01-01

    Liver kinetic study of [18F]2-fluoro-2-deoxy-D-glucose (FDG) metabolism in human body is an important tool for functional modeling and glucose metabolic rate estimation. In general, the arterial blood time-activity curve (TAC) and the tissue TAC are required as the input and output functions for the kinetic model. For liver study, however, the arterial-input may be not consistent with the actual model input because the liver has a dual blood supply from the hepatic artery (HA) and the portal vein (PV) to the liver. In this study, the result of model parameter estimation using dual-input function is compared with that using arterial-input function. First, a dynamic positron emission tomography (PET) experiment is performed after injection of FDG into the human body. The TACs of aortic blood, PV blood, and five regions of interest (ROIs) in liver are obtained from the PET image. Then, the dual-input curve is generated by calculating weighted sum of both the arterial and PV input curves. Finally, the five liver ROIs' kinetic parameters are estimated with arterial-input and dual-input functions respectively. The results indicate that the two methods provide different parameter estimations and the dual-input function may lead to more accurate parameter estimation.

  13. Quantitative assessment of systolic left ventricular function with speckle-tracking echocardiography in adult patients with repaired aortic coarctation.

    Science.gov (United States)

    Menting, Myrthe E; van Grootel, Roderick W J; van den Bosch, Annemien E; Eindhoven, Jannet A; McGhie, Jackie S; Cuypers, Judith A A E; Witsenburg, Maarten; Helbing, Willem A; Roos-Hesselink, Jolien W

    2016-05-01

    Despite successful aortic coarctation (CoA) repair, systemic hypertension often recurs which may influence left ventricular (LV) function. We aimed to detect early LV dysfunction using LV global longitudinal strain (GLS) in adults with repaired CoA, and to identify associations with patient and echocardiographic characteristics. In this cross-sectional study, patients with repaired CoA and healthy controls were recruited prospectively. All subjects underwent echocardiography, ECG and blood sampling within 1 day. With speckle-tracking echocardiography, we assessed LV GLS on the apical four-, three- and two-chamber views. We included 150 subjects: 75 patients (57 % male, age 33.4 ± 12.8 years, age at repair 2.5 [IQR: 0.1-11.1] years) and 75 healthy controls of similar sex and age. LV GLS was lower in patients than in controls (-17.1 ± 2.3 vs. -20.2 ± 1.6 %, P < 0.001). Eighty percent of the patients had a normal LV ejection fraction, but GLS was still lower than in controls (P < 0.001). In patients, GLS correlated with systolic and diastolic blood pressure (r = 0.32, P = 0.009; r = 0.31, P = 0.009), QRS duration (r = 0.34, P = 0.005), left atrial dimension (r = 0.27, P = 0.029), LV mass (r = 0.30, P = 0.014) and LV ejection fraction (r = -0.48, P < 0.001). Patients with either associated cardiac lesions, multiple cardiac interventions or aortic valve replacement had lower GLS than patients without. Although the majority of adults with repaired CoA seem to have a normal systolic LV function, LV GLS was decreased. Higher blood pressure, associated cardiac lesions, and larger left atrial dimension are related with lower GLS. Therefore, LV GLS may be used as objective criterion for early detection of ventricular dysfunction.

  14. Estimating the basilar-membrane input-output function in normal-hearing and hearing-impaired listeners

    DEFF Research Database (Denmark)

    Jepsen, Morten Løve; Dau, Torsten

    To partly characterize the function of cochlear processing in humans, the basilar membrane (BM) input-output function can be estimated. In recent studies, forward masking has been used to estimate BM compression. If an on-frequency masker is processed compressively, while an off-frequency masker...... processing at medium levels. If a signal can be masked by a low-level on-frequency masker such that signal and masker fall in the linear region of the I/O-function, then a steeper GOM function is expected. The knee-point can then be estimated in the input level region where the GOM changes significantly...... higher input levels and compression was similar to that of NH listeners....

  15. Aortic biomechanics in hypertrophic cardiomyopathy

    Science.gov (United States)

    Badran, Hala Mahfouz; Soltan, Ghada; Faheem, Nagla; Elnoamany, Mohamed Fahmy; Tawfik, Mohamed; Yacoub, Magdi

    2015-01-01

    Background: Ventricular-vascular coupling is an important phenomenon in many cardiovascular diseases. The association between aortic mechanical dysfunction and left ventricular (LV) dysfunction is well characterized in many disease entities, but no data are available on how these changes are related in hypertrophic cardiomyopathy (HCM). Aim of the work: This study examined whether HCM alone is associated with an impaired aortic mechanical function in patients without cardiovascular risk factors and the relation of these changes, if any, to LV deformation and cardiac phenotype. Methods: 141 patients with HCM were recruited and compared to 66 age- and sex-matched healthy subjects as control group. Pulse pressure, aortic strain, stiffness and distensibility were calculated from the aortic diameters measured by M-mode echocardiography and blood pressure obtained by sphygmomanometer. Aortic wall systolic and diastolic velocities were measured using pulsed wave Doppler tissue imaging (DTI). Cardiac assessment included geometric parameters and myocardial deformation (strain and strain rate) and mechanical dyssynchrony. Results: The pulsatile change in the aortic diameter, distensibility and aortic wall systolic velocity (AWS') were significantly decreased and aortic stiffness index was increased in HCM compared to control (P < .001) In HCM AWS' was inversely correlated to age(r = − .32, P < .0001), MWT (r = − .22, P < .008), LVMI (r = − .20, P < .02), E/Ea (r = − .16, P < .03) LVOT gradient (r = − 19, P < .02) and severity of mitral regurg (r = − .18, P < .03) but not to the concealed LV deformation abnormalities or mechanical dyssynchrony. On multivariate analysis, the key determinant of aortic stiffness was LV mass index and LVOT obstruction while the role LV dysfunction in aortic stiffness is not evident in this population. Conclusion: HCM is associated with abnormal aortic mechanical properties. The severity of cardiac

  16. Functional properties of GABA synaptic inputs onto GABA neurons in monkey prefrontal cortex

    NARCIS (Netherlands)

    D.C. Rotaru (Diana C.); C. Olezene (Cameron); T. Miyamae (Takeaki); N.V. Povysheva (Nadezhda V.); A.V. Zaitsev (Aleksey V.); D.A. Lewis (David A.); G. Gonzalez-Burgos (Guillermo)

    2015-01-01

    textabstractIn rodent cortex GABAA receptor (GABAAR)-mediated synapses are a significant source of input onto GABA neurons, and the properties of these inputs vary among GABA neuron subtypes that differ in molecular markers and firing patterns. Some features of cortical interne

  17. The study of left ventricular function before and after aortic valve replacement by echocardiography%超声心动图对主动脉瓣替换术后康复期患者

    Institute of Scientific and Technical Information of China (English)

    万维琴; 王尔松; 段义民; 贲道峰

    2001-01-01

    @@Background: Rheumatic aortic valve disease is one of factors which cause serious left ventricular(LV) functions insufficiency. Aortic valve replacement(AVR) is a therapy's method of treating aortic valve disease,and the echocardiography is an important method of evaluating curative effect of it. Objective: To evaluate the effect of AVR on left ventricular functions by echocardiography. Unit:Service Force Hospital of 61398 Army of PLA,Shanghai Subject: There were 33 patients with rheumatic aortic valve disease(insufficiency or stenosis) and accepting AVR in Changhai Hospital from 1997 to 1999,7 females and 26 males,aged range 13~ 69 years(mean age 39.5± 13.2 years).3 cases of II degree,25 of III degree,5 of IV degree for left ventricular functions by NYHA.

  18. Chaos and asymptotical stability in discrete-time recurrent neural networks with generalized input-output function

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    We theoretically investigate the asymptotical stability, localbifurcations and chaos of discrete-time recurrent neural networks with the form ofwhere the input-output function is defined as a generalized sigmoid function, such as vi=tanh(μiui), etc. Numerical simulations are also provided to demonstrate the theoretical results.

  19. Visual input controls the functional activity of goldfish Mauthner neuron through the reciprocal synaptic mechanism.

    Science.gov (United States)

    Moshkov, Dmitry A; Shtanchaev, Rashid S; Mikheeva, Irina B; Bezgina, Elena N; Kokanova, Nadezhda A; Mikhailova, Gulnara Z; Tiras, Nadezhda R; Pavlik, Lyubov' L

    2013-03-01

    Goldfish are known to exhibit motor asymmetry due to functional asymmetry of their Mauthner neurons that induce the turns to the right or left during free swimming. It has been previously found that if the less active neuron is subjected to prolonged aimed visual stimulation via its ventral dendrite, the motor asymmetry of goldfish is inverted, testifying that this neuron becomes functionally dominant, while the size of the ventral dendrite under these conditions is reduced 2-3 times compared to its counterpart in mirror neuron. Earlier it has been also revealed that training optokinetic stimulation induces adaptation, a substantial resistance of both fish motor asymmetry and morphofunctional state of Mauthner neurons against prolonged optokinetic stimulation. The aim of this work was to study the cellular mechanisms of the effect of an unusual visual afferent input on goldfish motor asymmetry and Mauthner neuron function in norm and under adaptation. It was shown that serotonin applied onto Mauthner neurons greatly reduces their activity whereas its antagonist ondansetron increases it. Against the background of visual stimulation, serotonin strengthens functional asymmetry between neurons whereas ondansetron smoothes it. Taken together these data suggest the involvement of serotonergic excitatory synaptic transmission in the regulation of Mauthner neurons by vision. Ultrastructural study of the ventral dendrites after prolonged optokinetic stimulation has revealed depletions of numeral axo-axonal synapses with specific morphology, identified by means of immunogold label as serotonergic ones. These latter in turn are situated mainly on shaft boutons, which according to specific ultrastructural features are assigned to axo-dendritic inhibitory synapses. Thus, the excitatory serotonergic synapses seem to affect Mauthner neuron indirectly through inhibitory synapses. Further, it was morphometrically established that adaptation is accompanied by the significant

  20. Functional identification of the input-output transforms of motoneurones in the rat and cat.

    Science.gov (United States)

    Poliakov, A V; Powers, R K; Binder, M D

    1997-10-15

    associated PSTH. This linear model provided good matches to the PSTHs associated with a wide range of current transients. However, for the largest amplitude current transients, a significant improvement in the PSTH match was often achieved by expanding the model to include the convolution of the second-order Wiener kernel with the input. 4. The overall transformation of current inputs into firing rate could be approximated by a second-order Wiener model, i.e. a cascade of a dynamic, linear filter followed by a static non-linearity. At a given mean firing rate, the non-linear component of the response of the motoneurone could be described by the square of the linear component multiplied by a constant coefficient. The amplitude of the response of the linear component increased with the average firing rate, whereas the value of the multiplicative coefficient in the non-linear component decreased. As a result, the overall transform could be predicted from the mean firing rate and the linear impulse response, yielding a relatively simple, general description of the motoneurone input-output function.

  1. Bicuspid Aortic Valve

    Science.gov (United States)

    2006-08-01

    aortic valvular disease, endocarditis, ascending aortic aneurysm and aortic dissection.1-4 There is also an association of BAV with coarctation of...for aortic aneurysm , patients with BAV appear to have additional risks for aortic disease. Nistri et al.12 reported significant aortic root...Congenital heart disease in patients with Turner’s syndrome. Italian study group for Turner syndrome (ISGTS). J Pediatr 1998; 133:688-692. 7. Schmid

  2. Aortic Stenosis.

    Science.gov (United States)

    Bakaeen, Faisal G; Rosengart, Todd K; Carabello, Blase A

    2017-01-03

    This issue provides a clinical overview of aortic stenosis, focusing on screening, diagnosis, treatment, and practice improvement. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers.

  3. Porphyromonas gingivalis infection modifies oral microcirculation and aortic vascular function in the stroke-prone spontaneously hypertensive rat (SHRSP).

    Science.gov (United States)

    Funaki, Seiko; Tokutomi, Fumiaki; Wada-Takahashi, Satoko; Yoshino, Fumihiko; Yoshida, Ayaka; Maehata, Yojiro; Miyamoto, Chihiro; Toyama, Toshizo; Sato, Takenori; Hamada, Nobushiro; Lee, Masaichi Chang-il; Takahashi, Shun-suke

    2016-03-01

    The functional modulation of vascular endothelial cells associated with stroke and periodontal disease has not yet been clarified. The objective of this study is to analyze the vascular endothelial function of periodontitis and stroke animal models. We examined endothelial function and gingival blood flow in oral microcirculation in vivo and measured the isometric tension in vitro of the aorta in animal models for lifestyle-related diseases, such as periodontitis and stroke. Gingival reactive hyperemia (GRH) was measured using laser Doppler flowmetry. Wistar Kyoto rats (WKY) were used as control animals; Porphyromonas gingivalis (P. gingivalis) infected WKY (WKY + Pg) as the periodontitis model; stroke-prone spontaneously hypertensive rat (SHRSP) as the stroke model; and a final group consisting of P. gingivalis infected SHRSP (SHRSP + Pg). Furthermore, for each group, the relaxation of descending aortic ring preparations was measured using a force transducer. The GRH was estimated by maximum response (peak), time taken for the maximum response to fall to one half (T1/2), and increased total amount of blood flow (mass). The relative change in T1/2 and mass increased in SHRSP + Pg compared to WKY. However, mass significantly increased in WKY (758.59 ± 88.21 ml/min/100 g s to 1755.55 ± 226.10 ml/min/100 g s) and SHRSP (1214.87 ± 141.61 ml/min/100 g s to 2674.32 ± 675.48 ml/min/100 g s) after treatment with acetylcholine. In addition, T1/2 and mass significantly increased in WKY + Pg (624.18 ± 96.36 ml/min/100 g s to 2629.90 ± 612.01 ml/min/100 g s) and SHRSP + Pg (1116.36 ± 206.24 ml/min/100 g s to 1952.76 ± 217.39 ml/min/100 g s) after treatment with nitroglycerin. Furthermore, the endothelium-dependent relaxation of ring preparations, evoked by acetylcholine, was attenuated in SHRSP compared with WKY, but not in SHRSP + Pg. This attenuation effect in SHRSP could be prevented by superoxide dismutase pretreatment. Our results suggest altered endothelial

  4. Effect of dynamic keyboard and word-prediction systems on text input speed in persons with functional tetraplegia.

    Science.gov (United States)

    Pouplin, Samuel; Robertson, Johanna; Antoine, Jean-Yves; Blanchet, Antoine; Kahloun, Jean Loup; Volle, Philippe; Bouteille, Justine; Lofaso, Frédéric; Bensmail, Djamel

    2014-01-01

    Information technology plays a very important role in society. People with disabilities are often limited by slow text input speed despite the use of assistive devices. This study aimed to evaluate the effect of a dynamic on-screen keyboard (Custom Virtual Keyboard) and a word-prediction system (Sibylle) on text input speed in participants with functional tetraplegia. Ten participants tested four modes at home (static on-screen keyboard with and without word prediction and dynamic on-screen keyboard with and without word prediction) for 1 mo before choosing one mode and then using it for another month. Initial mean text input speed was around 23 characters per minute with the static keyboard and 12 characters per minute with the dynamic keyboard. The results showed that the dynamic keyboard reduced text input speed by 37% compared with the standard keyboard and that the addition of word prediction had no effect on text input speed. We suggest that current forms of dynamic keyboards and word prediction may not be suitable for increasing text input speed, particularly for subjects who use pointing devices. Future studies should evaluate the optimal ergonomic design of dynamic keyboards and the number and position of words that should be predicted.

  5. Staphylococcal β-Toxin Modulates Human Aortic Endothelial Cell and Platelet Function through Sphingomyelinase and Biofilm Ligase Activities

    Science.gov (United States)

    Herrera, Alfa; Kulhankova, Katarina; Sonkar, Vijay K.; Dayal, Sanjana; Klingelhutz, Aloysius J.; Salgado-Pabón, Wilmara

    2017-01-01

    ABSTRACT Staphylococcus aureus causes many infections, such as skin and soft tissue, pneumonia, osteomyelitis, and infective endocarditis (IE). IE is an endovascular infection of native and prosthetic valves and the lining of the heart; it is characterized by the formation of cauliflower-like “vegetations” composed of fibrin, platelets, other host factors, bacteria, and bacterial products. β-Toxin is an S. aureus virulence factor that contributes to the microorganism’s ability to cause IE. This cytolysin has two enzymatic activities: sphingomyelinase (SMase) and biofilm ligase. Although both activities have functions in a rabbit model of IE, the mechanism(s) by which β-toxin directly affects human cells and is involved in the infectious process has not been elucidated. Here, we compared the in vitro effects of purified recombinant wild-type β-toxin, SMase-deficient β-toxin (H289N), and biofilm ligase-deficient β-toxin (H162A and/or D163A) on human aortic endothelial cells (HAECs) and platelets. β-Toxin was cytotoxic to HAECs and inhibited the production of interleukin 8 (IL-8) from these cells by both SMase and biofilm ligase activities. β-Toxin altered HAEC surface expression of CD40 and vascular cell adhesion molecule 1 (VCAM-1). HAECs treated with β-toxin displayed granular membrane morphology not seen in treatment with the SMase-deficient mutant. The altered morphology resulted in two possibly separable activities, cell rounding and redistribution of cell membranes into granules, which were not the result of endosome production from the Golgi apparatus or lysosomes. β-Toxin directly aggregated rabbit platelets via SMase activity. PMID:28325766

  6. Aortic annuloplasty with aortic root reconstruction to prevent patient-prosthesis mismatch.

    Science.gov (United States)

    Hopkins, Richard A

    2006-07-01

    Part of the ongoing argument concerning patient-prosthesis mismatch (PPM) following aortic valve replacement (AVR) is due to the perception that aortic annulus enlargement procedures increase the risk and technical difficulty of aortic valve surgery. Here, an aortic root reconstruction that involves enlargement of the annulus and tailoring of the aortic root to accommodate larger stented prostheses is presented that has been personally performed in 196 patients with no technique-related surgical deaths or complications, and thus can be carried out without additional risk. This aortic root enlargement aortoplasty and annuloplasty method can be calibrated to all AVRs involving stented manufactured prostheses when these are deemed the prosthesis of choice for the patient with a relatively small annulus and/or aortic root, severe left ventricular hypertrophy, compromised LV function or a very active lifestyle, to achieve predicted EOA values > or = 1.00 cm2/m2.

  7. Ranking Hearing Aid Input-Output Functions for Understanding Low-, Conversational-, and High-Level Speech in Multitalker Babble

    Science.gov (United States)

    Chung, King; Killion, Mead C.; Christensen, Laurel A.

    2007-01-01

    Purpose: To determine the rankings of 6 input-output functions for understanding low-level, conversational, and high-level speech in multitalker babble without manipulating volume control for listeners with normal hearing, flat sensorineural hearing loss, and mildly sloping sensorineural hearing loss. Method: Peak clipping, compression limiting,…

  8. Relative sensitivities of DCE-MRI pharmacokinetic parameters to arterial input function (AIF) scaling.

    Science.gov (United States)

    Li, Xin; Cai, Yu; Moloney, Brendan; Chen, Yiyi; Huang, Wei; Woods, Mark; Coakley, Fergus V; Rooney, William D; Garzotto, Mark G; Springer, Charles S

    2016-08-01

    Dynamic-Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) has been used widely for clinical applications. Pharmacokinetic modeling of DCE-MRI data that extracts quantitative contrast reagent/tissue-specific model parameters is the most investigated method. One of the primary challenges in pharmacokinetic analysis of DCE-MRI data is accurate and reliable measurement of the arterial input function (AIF), which is the driving force behind all pharmacokinetics. Because of effects such as inflow and partial volume averaging, AIF measured from individual arteries sometimes require amplitude scaling for better representation of the blood contrast reagent (CR) concentration time-courses. Empirical approaches like blinded AIF estimation or reference tissue AIF derivation can be useful and practical, especially when there is no clearly visible blood vessel within the imaging field-of-view (FOV). Similarly, these approaches generally also require magnitude scaling of the derived AIF time-courses. Since the AIF varies among individuals even with the same CR injection protocol and the perfect scaling factor for reconstructing the ground truth AIF often remains unknown, variations in estimated pharmacokinetic parameters due to varying AIF scaling factors are of special interest. In this work, using simulated and real prostate cancer DCE-MRI data, we examined parameter variations associated with AIF scaling. Our results show that, for both the fast-exchange-limit (FXL) Tofts model and the water exchange sensitized fast-exchange-regime (FXR) model, the commonly fitted CR transfer constant (K(trans)) and the extravascular, extracellular volume fraction (ve) scale nearly proportionally with the AIF, whereas the FXR-specific unidirectional cellular water efflux rate constant, kio, and the CR intravasation rate constant, kep, are both AIF scaling insensitive. This indicates that, for DCE-MRI of prostate cancer and possibly other cancers, kio and kep may be more suitable imaging

  9. Relative sensitivities of DCE-MRI pharmacokinetic parameters to arterial input function (AIF) scaling

    Science.gov (United States)

    Li, Xin; Cai, Yu; Moloney, Brendan; Chen, Yiyi; Huang, Wei; Woods, Mark; Coakley, Fergus V.; Rooney, William D.; Garzotto, Mark G.; Springer, Charles S.

    2016-08-01

    Dynamic-Contrast-Enhanced Magnetic Resonance Imaging (DCE-MRI) has been used widely for clinical applications. Pharmacokinetic modeling of DCE-MRI data that extracts quantitative contrast reagent/tissue-specific model parameters is the most investigated method. One of the primary challenges in pharmacokinetic analysis of DCE-MRI data is accurate and reliable measurement of the arterial input function (AIF), which is the driving force behind all pharmacokinetics. Because of effects such as inflow and partial volume averaging, AIF measured from individual arteries sometimes require amplitude scaling for better representation of the blood contrast reagent (CR) concentration time-courses. Empirical approaches like blinded AIF estimation or reference tissue AIF derivation can be useful and practical, especially when there is no clearly visible blood vessel within the imaging field-of-view (FOV). Similarly, these approaches generally also require magnitude scaling of the derived AIF time-courses. Since the AIF varies among individuals even with the same CR injection protocol and the perfect scaling factor for reconstructing the ground truth AIF often remains unknown, variations in estimated pharmacokinetic parameters due to varying AIF scaling factors are of special interest. In this work, using simulated and real prostate cancer DCE-MRI data, we examined parameter variations associated with AIF scaling. Our results show that, for both the fast-exchange-limit (FXL) Tofts model and the water exchange sensitized fast-exchange-regime (FXR) model, the commonly fitted CR transfer constant (Ktrans) and the extravascular, extracellular volume fraction (ve) scale nearly proportionally with the AIF, whereas the FXR-specific unidirectional cellular water efflux rate constant, kio, and the CR intravasation rate constant, kep, are both AIF scaling insensitive. This indicates that, for DCE-MRI of prostate cancer and possibly other cancers, kio and kep may be more suitable imaging

  10. Image-derived input function obtained in a 3TMR-brainPET

    Energy Technology Data Exchange (ETDEWEB)

    Silva, N.A. da [Institute of Biophysics and Biomedical Engineering, University of Lisbon (Portugal); Institute of Neurosciences and Medicine - 4, Juelich (Germany); Herzog, H., E-mail: h.herzog@fz-juelich.de [Institute of Neurosciences and Medicine - 4, Juelich (Germany); Weirich, C.; Tellmann, L.; Rota Kops, E. [Institute of Neurosciences and Medicine - 4, Juelich (Germany); Hautzel, H. [Department of Nuclear Medicine (KME), University of Duesseldorf, Medical Faculty at Research Center Juelich, Juelich (Germany); Almeida, P. [Institute of Biophysics and Biomedical Engineering, University of Lisbon (Portugal)

    2013-02-21

    Aim: The combination of a high-resolution MR-compatible BrainPET insert operated within a 3 T MAGNETOM Trio MR scanner is an excellent tool for obtaining an image derived input function (IDIF), due to simultaneous imaging. In this work, we explore the possibility of obtaining an IDIF from volumes of interest (VOI) defined over the carotid arteries (CAs) using the MR data. Material and methods: FDG data from three patients without brain disorders were included. VOIs were drawn bilaterally over the CAs on a MPRAGE image using a 50% isocontour (MR50VOI). CA PET/MR co-registration was examined based on an individual and combined CA co-registration. After that, to estimate the IDIF, the MR50VOI average (IDIF-A), four hottest pixels per plane (IDIF-4H) and four hottest pixels in VOI (IDIF-4V) were considered. A model-based correction for residual partial volume effects involving venous blood samples was applied, from which partial volume (PV) and spillover (SP) coefficients were estimated. Additionally, a theoretical PV coefficient (PVt) was calculated based on MR50VOI. Results: The results show an excellent co-registration between the MR and PET, with an area under the curve ratio between both co-registration methods of 1.00±0.04. A good agreement between PV and PVt was found for IDIF-A, with PV of 0.39±0.06 and PVt 0.40±0.03, and for IDIF-4H, with PV of 0.47±0.05 and PVt 0.47±0.03. The SPs were 0.20±0.03 and 0.21±0.03 for IDIF-A and IDIF-4H, respectively. Conclusion: The integration of a high resolution BrainPET in an MR scanner allows to obtain an IDIF from an MR-based VOI. This must be corrected for a residual partial volume effect.

  11. Arterial Input Function Placement for Accurate CT Perfusion Map Construction in Acute Stroke

    Science.gov (United States)

    Ferreira, Rafael M.; Lev, Michael H.; Goldmakher, Gregory V.; Kamalian, Shahmir; Schaefer, Pamela W.; Furie, Karen L.; Gonzalez, R. Gilberto; Sanelli, Pina C.

    2013-01-01

    OBJECTIVE The objective of our study was to evaluate the effect of varying arterial input function (AIF) placement on the qualitative and quantitative CT perfusion parameters. MATERIALS AND METHODS Retrospective analysis of CT perfusion data was performed on 14 acute stroke patients with a proximal middle cerebral artery (MCA) clot. Cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) maps were constructed using a systematic method by varying only the AIF placement in four positions relative to the MCA clot including proximal and distal to the clot in the ipsilateral and contralateral hemispheres. Two postprocessing software programs were used to evaluate the effect of AIF placement on perfusion parameters using a delay-insensitive deconvolution method compared with a standard deconvolution method. RESULTS One hundred sixty-eight CT perfusion maps were constructed for each software package. Both software programs generated a mean CBF at the infarct core of < 12 mL/100 g/min and a mean CBV of < 2 mL/100 g for AIF placement proximal to the clot in the ipsilateral hemisphere and proximal and distal to the clot in the contralateral hemisphere. For AIF placement distal to the clot in the ipsilateral hemisphere, the mean CBF significantly increased to 17.3 mL/100 g/min with delay-insensitive software and to 19.4 mL/100 g/min with standard software (p < 0.05). The mean MTT was significantly decreased for this AIF position. Furthermore, this AIF position yielded qualitatively different parametric maps, being most pronounced with MTT and CBF. Overall, CBV was least affected by AIF location. CONCLUSION For postprocessing of accurate quantitative CT perfusion maps, laterality of the AIF location is less important than avoiding AIF placement distal to the clot as detected on CT angiography. This pitfall is less severe with deconvolution-based software programs using a delay-insensitive technique than with those using a standard deconvolution

  12. Metformin improves endothelial function in aortic tissue and microvascular endothelial cells subjected to diabetic hyperglycaemic conditions.

    Science.gov (United States)

    Ghosh, Suparna; Lakshmanan, Arun P; Hwang, Mu Ji; Kubba, Haidar; Mushannen, Ahmed; Triggle, Chris R; Ding, Hong

    2015-12-01

    The cellular mechanisms whereby metformin, the first line drug for type 2 diabetes (T2DM), mediates its antidiabetic effects remain elusive, particularly as to whether metformin has a direct protective action on the vasculature. This study was designed to determine if a brief 3-h exposure to metformin protects endothelial function against the effects of hyperglycaemia. We investigated the protective effects of metformin on endothelial-dependent vasodilatation (EDV) in thoracic aortae from T2DM db/db mice and on high glucose (HG, 40 mM) induced changes in endothelial nitric oxide synthase (eNOS) signaling in mouse microvascular endothelial cells (MMECs) in culture. Exposure of aortae from db+/? non-diabetic control mice to high glucose (HG, 40 mM) containing Krebs for 3-h significantly (Pmetformin; metformin also improved ACh-induced EDV in aortae from diabetic db/db mice. Immunoblot analysis of MMECs cultured in HG versus NG revealed a significant reduction of the ratio of phosphorylated (p-eNOS)/eNOS and p-Akt/Akt, but not the expression of total eNOS or Akt. The 3-h exposure of MMECs to metformin significantly (Pmetformin can reverse/reduce the impact of HG on endothelial function, via mechanisms linked to increased phosphorylation of eNOS and Akt.

  13. Altered diastolic function and aortic stiffness in Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    Çalık AN

    2014-07-01

    Full Text Available Ali Nazmi Çalik,3 Kazim Serhan Özcan,4 Gülbün Yüksel,2 Baris Güngör,1 Emre Arugarslan,1 Figen Varlibas,2 Ahmet Ekmekci,1 Damirbek Osmonov,1 Mustafa Adem Tatlisu,1 Mehmet Karaca,1 Osman Bolca,1 Izzet Erdinler1 1Department of Cardiology, Siyami Ersek Cardiovascular and Thoracic Surgery Center, Istanbul, Turkey; 2Department of Neurology, Haydarpasa Numune Training and Research Hospital, Istanbul, Turkey; 3Department of Cardiology, Yozgat State Hospital, Yozgat, Turkey; 4Department of Cardiology, Derince Training and Research Hospital, Kocaeli, Turkey Background: Alzheimer’s disease (AD is closely linked to cardiovascular risk factors.Methods: Echocardiographic studies were performed, including left ventricular diastolic functions, left and right atrial conduction times, and arterial stiffness parameters, namely stiffness index, pressure-strain elastic modulus, and distensibility, on 29 patients with AD and 24 age-matched individuals with normal cognitive function.Results: The peak mitral flow velocity of the early rapid filling wave (E was lower, and the peak velocity of the late filling wave caused by atrial contraction (A, deceleration time of peak E velocity, and isovolumetric relaxation time were higher in the AD group. The early myocardial peak (Ea velocity was significantly lower in AD patients, whereas the late diastolic (Aa velocity and E/Ea ratio were similar between the two groups. In Alzheimer patients, stiffness index and pressure-strain elastic modulus were higher, and distensibility was significantly lower in the AD group compared to the control. Interatrial electromechanical delay was significantly longer in the AD group.Conclusion: Our findings suggest that patients with AD are more likely to have diastolic dysfunction, higher atrial conduction times, and increased arterial stiffness compared to the controls of same sex and similar age. Keywords: diastolic dysfunction, atrial conduction timeA Letter to the Editor has been

  14. Aortic valve bypass

    DEFF Research Database (Denmark)

    Lund, Jens T; Jensen, Maiken Brit; Arendrup, Henrik;

    2013-01-01

    In aortic valve bypass (AVB) a valve-containing conduit is connecting the apex of the left ventricle to the descending aorta. Candidates are patients with symptomatic aortic valve stenosis rejected for conventional aortic valve replacement (AVR) or transcatheter aortic valve implantation (TAVI...

  15. Beating Heart Mitral Valve Replacement Surgery without Aortic Cross-Clamping via Right Thoracotomy in a Patient with Compromised Left Ventricular Functions

    Directory of Open Access Journals (Sweden)

    Ahmet Baris-Durukan

    2015-10-01

    Full Text Available Global myocardial ischemia and ischemia-reperfusion injury are potential adverse events related with cardioplegic arrest. Beating heart surgery has avoided such complications and adapted to valve surgery following successful results published on myocardial revascularization. Difficulty in weaning from cardiopulmonary bypass may be lessened by using on-pump beating heart surgery for mitral valve interventions. Here we describe a 64-year-old male patient with severe mitral regurgitation and dilated cardiomyopathy. Beating heart mitral valve replacement surgery was performed without aortic cross-clamping through a right thoracotomy approach. We believe that, particularly in patients with poor left ventricular functions, beating heart mitral valve surgery may be advantageous

  16. Aortic stenosis. Gender influence on left ventricular geometry and function in patients under 70 years of age

    Directory of Open Access Journals (Sweden)

    Rocha Antonio Sérgio Cordeiro da

    1999-01-01

    Full Text Available OBJECTIVE: To verify if adaptive left ventricle (LV characteristics are also present in individuals under 70 years of age with severe aortic stenosis (AS. METHODS: The study comprised 40 consecutive patients under 70 years of age with AS and no associated coronary artery disease, referred for valve surgery. Out of the 40 patients, 22 were men and 18 women, and the mean age was 49.8±14.3 years. Cardiac symptoms, presence of systemic hypertension (SH, functional class according to the New York Heart Association (NYHA, and valve lesion etiology were considered. LV cavity dimensions, ejection fraction (EF, fractional shortening (FS, mass (MS, and relative diastolic thickness (RDT were examined by Doppler echocardiography. RESULTS: Fourteen (63.6% men and 11 (61.6% women were classified as NYHA class III/IV (p=0.70. There was no difference in the frequency of angina, syncope or dyspnea between genders. The incidence of SH was greater in women than in men (10 versus 2, p=0.0044. Women had a smaller LV end-diastolic diameter index (32.1±6.5 x 36.5±5.3mm/m², p=0.027, LV end-systolic diameter index (19.9±5.9 x 26.5±6.4mm/m², p=0.0022 and LV mass index (MS (211.4±71.1 x 270.9±74.9g/m², p=0.017 when compared with men. EF (66.2±13.4 x 52.0±14.6%, p=0.0032, FS (37.6±10.7 x 27.9±9.6%, p=0.0046 and RDT (0.58±0.22 x 0.44±0.09, p=0.0095 were significantly greater in women than in men. CONCLUSION: It is the patient gender rather than age that influences left ventricular adaptive response to AS.

  17. Hemodynamic function of the standard St. Jude bileaflet disc valve has no clinical impact 10 years after aortic valve replacement

    DEFF Research Database (Denmark)

    Lund, Ole; Dorup, Inge; Emmertsen, Kristian

    2005-01-01

    in the survivors of a prospective series 10 years after AVR for aortic stenosis. DESIGN: Forty-three survivors aged 32-90 years from a prospective series attended a follow-up study with Doppler echo and radionuclide cardiography 10 years after AVR for aortic stenosis. Six patients with significant left sided valve...... regurgitation were excluded from further analysis: they had significantly lower St. Jude valve gradient and left ventricular ejection fraction (LVEF) and larger mass index (LVMi) than 37 without. RESULTS: In the 37 patients without left sided valve regurgitation peak and mean gradients were inversely related...... to St. Jude valve geometric orifice area (GOA) indexed for either body surface area or left ventricular end-diastolic dimension (LVEDD). The gradients correlated directly with LVEDD but not with LVEF or LVMi. Eleven patients with hypertension had higher peak gradients (31+/-13 versus 22+/-8 mmHg, p

  18. Transcatheter aortic valve implantation: role of multi-detector row computed tomography to evaluate prosthesis positioning and deployment in relation to valve function.

    NARCIS (Netherlands)

    Delgado, V.; Ng, A.C.; Veire, N.R. van de; Kley, F. van der; Schuijf, J.D.; Tops, L.F.; Weger, A. de; Tavilla, G.; Roos, A. de; Kroft, L.J.; Schalij, M.J.; Bax, J.J.

    2010-01-01

    AIMS: Aortic regurgitation after transcatheter aortic valve implantation (TAVI) is one of the most frequent complications. However, the underlying mechanisms of this complication remain unclear. The present evaluation studied the anatomic and morphological features of the aortic valve annulus that m

  19. Simultaneous acquisition of dynamic PET-MRI: arterial input function using DSC-MRI and [18F]-FET

    Energy Technology Data Exchange (ETDEWEB)

    Caldeira, Liliana; Yun, Seong Dae; Silva, Nuno da; Filss, Christian; Scheins, Juergen; Telmann, Lutz; Herzog, Hans; Shah, Jon [Institute of Neuroscience and Medicine - 4, Forschungszentrum Juelich GmbH (Germany)

    2015-05-18

    This work focuses on the study of simultaneous dynamic MR-PET acquisition in brain tumour patients. MR-based perfusion-weighted imaging (PWI) and PET [18F]-FET are dynamic methods, which allow to evaluate tumour metabolism in a quantitative way. In both methods, arterial input function (AIF) is necessary for quantification. However, the AIF estimation is a challenging task. In this work, we explore the possibilities to combine dynamic MR and PET AIF.

  20. [Aortic valve replacement as an independent predictive factor for later development of aortic dissection].

    Science.gov (United States)

    von Kodolitsch, Y; Simic, O; Bregenzer, T; Dresler, C; Haverich, A; Nienaber, C A

    1998-08-01

    Dissection of the ascending aorta (type A) following later after aortic valve replacement has been described with increasing frequency. This study analyzes the role of aortic valve replacement for the evolution of late dissection. In a series of 80 consecutive patients with type A dissection, a previous aortic valve replacement had been performed in 12 cases (15%). In addition to arterial hypertension (p syndrome (p factor for type A dissection. Dissection occurred 3 +/- 4 years after aortic valve replacement with a clinical and anatomical profile similar to classic dissection as proven by comparison to a group of 62 patients with classic dissection associated with arterial hypertension or Marfan syndrome. With 75% and 66%, respectively, 30 day and 1 year survival of patients with dissection following later after aortic valve replacement was similar to patients with classic type A dissection. Extensive thinning and/or fragility (p associated with a high risk for late dissection; this finding was substantiated by comparison to a control group of 10 consecutive patients with a similarly dilated aortic root but no dissection. Type and diameter of valve prostheses, cross-clamp time, NYHA functional class, and left ventricular ejection fraction were unrelated to late dissection. Previous aortic valve replacement is an independent predisposing factor for a dissection of the ascending aorta later. At the time of aortic valve replacement, prophylactic replacement or wrapping of the ascending aorta should be considered in patients with a thinned/fragile aortic wall even without a markedly dilated aortic root.

  1. Aortic valve and ascending aortic root modeling from 3D and 3D+t CT

    Science.gov (United States)

    Grbic, Saša; Ionasec, Razvan I.; Zäuner, Dominik; Zheng, Yefeng; Georgescu, Bogdan; Comaniciu, Dorin

    2010-02-01

    Aortic valve disorders are the most frequent form of valvular heart disorders (VHD) affecting nearly 3% of the global population. A large fraction among them are aortic root diseases, such as aortic root aneurysm, often requiring surgical procedures (valve-sparing) as a treatment. Visual non-invasive assessment techniques could assist during pre-selection of adequate patients, planning procedures and afterward evaluation of the same. However state of the art approaches try to model a rather short part of the aortic root, insufficient to assist the physician during intervention planning. In this paper we propose a novel approach for morphological and functional quantification of both the aortic valve and the ascending aortic root. A novel physiological shape model is introduced, consisting of the aortic valve root, leaflets and the ascending aortic root. The model parameters are hierarchically estimated using robust and fast learning-based methods. Experiments performed on 63 CT sequences (630 Volumes) and 20 single phase CT volumes demonstrated an accuracy of 1.45mm and an performance of 30 seconds (3D+t) for this approach. To the best of our knowledge this is the first time a complete model of the aortic valve (including leaflets) and the ascending aortic root, estimated from CT, has been proposed.

  2. [Chronic aortic and mitral valve regurgitation. Effects of isosorbide dinitrate on systolic function and passive elastic properties of the left ventricle (author's transl)].

    Science.gov (United States)

    Herreman, F; Cosma, H; Degeorges, M

    1982-06-10

    A haemodynamic and cineangiographic study was conducted in 20 patients with chronic aortic regurgitation alone or associated with mitral regurgitation before and during i.v. administration of isosorbide dinitrate 5 mg/hour. Freedom from coronary disease had been ascertained. The heart rate and aortic pressure (initially normal), cardiac index (initially low), pulmonary pressures and pulmonary and systemic resistances (slightly raised initially) remained unchanged. On the other hand, the left ventricular (LV) filling pressure, distinctly raised before treatment, was reduced by 17% (p less than 0.05). There was also a 10% reduction in LV end-diastolic volume (from 204 +/- 60- cm3.m2 to 184 +/- 56 cm3,m2; p less than 0.001) and a 14% reduction in LV end-systolic volume (from 104 +/- 39 cm3.m2 to 89 +/- 40 cm3.m3; p less than 0.001). LV geometry, stroke volume and regurgitation volume were unmodified. There was a significant improvement in ventricular function indices, globally reduced before treatment: + 8% for the fiber shortening amplitude (p less than 0.025), + 6% for the ejection fraction (p fiber shortening (p less than 0.01), and + 15% for the ESP: ESV ratio (p less than 0.05). The passive elasticity indices, all increased before treatment, also improved. It is concluded that isosorbide dinitrate improves LV systolic and diastolic functions in patients with chronic valve disease.

  3. A new procedure for automatic fitting of the basilar-membrane input-output function to individual behavioral data

    DEFF Research Database (Denmark)

    Kowalewski, Borys; Fereczkowski, Michal; MacDonald, Ewen;

    2016-01-01

    system and, potentially, for clinical diagnostics. Computational algorithms are available that mimic the functioning of the nonlinear cochlear processing. One such algorithm is the dual resonance non-linear (DRNL) filterbank [6]. Its parameters can be modified to account for individual hearing loss, e...... parameters is difficult. Until recently, the parameters were manually adjusted and the fitting process was indirect. A new approach is described here, based on a search through a lookup table of pre-computed filterbank input-output functions. The aim of this approach is to provide a fast, stable, and more...

  4. Evaluating input device usability as a function of task difficulty in a tracking task.

    Science.gov (United States)

    Rupp, Michael A; Oppold, Paul; McConnell, Daniel S

    2015-01-01

    Game controllers are emerging as a preferred choice for the manual control of unmanned vehicles, but an understanding of their usability characteristics has yet to emerge. We compared the usability of an Xbox 360 game controller in a dual task situation using MATB II to the traditional joystick and keyboard interface in two experiments. In the first experiment, performance with the game controller was associated with fewer tracking errors. In a second experiment, we trained users on the devices, and found that even after training the game controller was still associated with fewer tracking errors as well as higher usability and lower workload ratings. These results are consistent with the idea that game controllers are highly usable input devices and do not require high mental workload to operate, thus making them suitable for complex control tasks.

  5. Generalized Cobb-Douglas Function for Two Inputs and Linear Elasticity

    Directory of Open Access Journals (Sweden)

    Catalin Angelo Ioan

    2014-12-01

    Full Text Available The article deals with a production function of two factors with constant scale return where the elasticity of one of the factors is a function of first degree. After the examination of parameters conditions according to the axioms of the production functions, there are computed the main indicators. Also, the combination of factors is determined in order to maximize the total output under a given cost.

  6. Origin and function of short-latency inputs to the neural substrates underlying the acoustic startle reflex

    Directory of Open Access Journals (Sweden)

    Ricardo eGómez-Nieto

    2014-07-01

    Full Text Available The acoustic startle reflex (ASR is a survival mechanism of alarm, which rapidly alerts the organism to a sudden loud auditory stimulus. In rats, the primary ASR circuit encompasses three serially connected structures: cochlear root neurons (CRNs, neurons in the caudal pontine reticular nucleus (PnC, and motoneurons in the medulla and spinal cord. It is well established that both CRNs and PnC neurons receive short-latency auditory inputs to mediate the ASR. Here, we investigated the anatomical origin and functional role of these inputs using a multidisciplinary approach that combines morphological, electrophysiological and behavioural techniques. Anterograde tracer injections into the cochlea suggest that CRNs somata and dendrites receive inputs depending, respectively, on their basal or apical cochlear origin. Confocal colocalization experiments demonstrated that these cochlear inputs are immunopositive for the vesicular glutamate transporter 1. Using extracellular recordings in vivo followed by subsequent tracer injections, we investigated the response of PnC neurons after contra-, ipsi-, and bilateral acoustic stimulation and identified the source of their auditory afferents. Our results showed that the binaural firing rate of PnC neurons was higher than the monaural, exhibiting higher spike discharges with contralateral than ipsilateral acoustic stimulations. Our histological analysis confirmed the CRNs as the principal source of short-latency acoustic inputs, and indicated that other areas of the cochlear nucleus complex are not likely to innervate PnC. Behaviourally, we observed a strong reduction of ASR amplitude in monaural earplugged rats that corresponds with the binaural summation process shown in our electrophysiological findings. Our study contributes to understand better the role of neuronal mechanisms in auditory alerting behaviours and provides strong evidence that the CRNs-PnC pathway mediates fast neurotransmission and binaural

  7. Modulation of the input-output function by GABAA receptor-mediated currents in rat oculomotor nucleus motoneurons.

    Science.gov (United States)

    Torres-Torrelo, Julio; Torres, Blas; Carrascal, Livia

    2014-11-15

    The neuronal input-output function depends on recruitment threshold and gain of the firing frequency-current (f-I) relationship. These two parameters are positively correlated in ocular motoneurons (MNs) recorded in alert preparation and inhibitory inputs could contribute to this correlation. Phasic inhibition mediated by γ-amino butyric acid (GABA) occurs when a high concentration of GABA at the synaptic cleft activates postsynaptic GABAA receptors, allowing neuronal information transfer. In some neuronal populations, low concentrations of GABA activate non-synaptic GABAA receptors and generate a tonic inhibition, which modulates cell excitability. This study determined how ambient GABA concentrations modulate the input-output relationship of rat oculomotor nucleus MNs. Superfusion of brain slices with GABA (100 μm) produced a GABAA receptor-mediated current that reduced the input resistance, increased the recruitment threshold and shifted the f-I relationship rightward without any change in gain. These modifications did not depend on MN size. In absence of exogenous GABA, gabazine (20 μm; antagonist of GABAA receptors) abolished spontaneous inhibitory postsynaptic currents and revealed a tonic current in MNs. Gabazine increased input resistance and decreased recruitment threshold mainly in larger MNs. The f-I relationship shifted to the left, without any change in gain. Gabazine effects were chiefly due to MN tonic inhibition because tonic current amplitude was five-fold greater than phasic. This study demonstrates a tonic inhibition in ocular MNs that modulates cell excitability depending on cell size. We suggest that GABAA tonic inhibition acting concurrently with glutamate receptors activation could reproduce the positive covariation between threshold and gain reported in alert preparation.

  8. Aortic Annular Enlargement during Aortic Valve Replacement

    Directory of Open Access Journals (Sweden)

    Selman Dumani

    2016-09-01

    Full Text Available In the surgery of aortic valve replacement is always attempted, as much as possible, to implant the larger prosthesis with the mains goals to enhance the potential benefits, to minimise transvalvular gradient, decrease left ventricular size and avoid the phenomenon of patient-prosthesis mismatch. Implantation of an ideal prosthesis often it is not possible, due to a small aortic annulus. A variety of aortic annulus enlargement techniques is reported to avoid patient-prosthesis mismatch. We present the case that has submitted four three times open heart surgery. We used Manouguian technique to enlarge aortic anulus with excellent results during the fourth time of surgery.

  9. Evaluation of aortic valve function in patients with bicuspid aortic valve with echocardiography%超声心动图评价二瓣化主动脉瓣瓣膜功能

    Institute of Scientific and Technical Information of China (English)

    朱美华; 邓又斌; 刘娅妮; 刘蓉; 熊莉; 朱英; 陈刘平; 伍玉晗

    2009-01-01

    目的 探讨超声心动图在二瓣化主动脉瓣病理生理进展评价中的应用,分析二瓣化主动脉瓣各年龄瓣膜病变的程度.方法 回顾性分析135例二瓣化主动脉瓣患者超声资料及病例资料,结合临床资料分析患者病程进展中瓣膜功能的变化.结果 二瓣化主动脉瓣关闭不全最常见,本组资料中为68例(50%),单纯狭窄仅19例(14%).狭窄并关闭不全者29例(22%),瓣膜功能正常者19例(14%).各年龄组内主动脉瓣病变均以关闭不全多见.病程晚期的手术患者各年龄组内主动脉病变亦均以关闭不全为主.结论 超声心动图能对主动脉瓣的病变作出早期诊断.二瓣化主动脉瓣最常见的瓣膜病变是主动脉瓣关闭不全.%Objective To evaluate the application of echocardiography in the diagnosis of bicuspid aortic valve and its pathophysiologic development and to demonstrate the degree of aortic valve dysfunction. Methods The echocardiographic characteristics and clinical data were analyzed retrospectively in 135 patients with bicuspid aortic valve to demonstrate the variation of aortic valve dysfunction in the progression of the course of the disease. Results Isolated aortic regurgitation was present in 68 (50%) patients, 19 (14%)patients had isolated aortic stenosis and 29 (22%)patients had combined aortic stenosis and regurgitation, 19 (14%) patients had neither stenosis nor regurgitation. Aortic regurgitation were all more commen within each age group, aortic regurgitation were also more commen within each age group in patients in their advanced course who went to surgical treatment. Conclusions Echocardiography is an effective method in the early diagnosis of aortic valve dysfunction.

  10. c-Myc Alters Substrate Utilization and O-GlcNAc Protein Posttranslational Modifications without Altering Cardiac Function during Early Aortic Constriction.

    Directory of Open Access Journals (Sweden)

    Dolena Ledee

    Full Text Available Hypertrophic stimuli cause transcription of the proto-oncogene c-Myc (Myc. Prior work showed that myocardial knockout of c-Myc (Myc attenuated hypertrophy and decreased expression of metabolic genes after aortic constriction. Accordingly, we assessed the interplay between Myc, substrate oxidation and cardiac function during early pressure overload hypertrophy. Mice with cardiac specific, inducible Myc knockout (MycKO-TAC and non-transgenic littermates (Cont-TAC were subjected to transverse aortic constriction (TAC; n = 7/group. Additional groups underwent sham surgery (Cont-Sham and MycKO-Sham, n = 5 per group. After two weeks, function was measured in isolated working hearts along with substrate fractional contributions to the citric acid cycle by using perfusate with 13C labeled mixed fatty acids, lactate, ketone bodies and unlabeled glucose and insulin. Cardiac function was similar between groups after TAC although +dP/dT and -dP/dT trended towards improvement in MycKO-TAC versus Cont-TAC. In sham hearts, Myc knockout did not affect cardiac function or substrate preferences for the citric acid cycle. However, Myc knockout altered fractional contributions during TAC. The unlabeled fractional contribution increased in MycKO-TAC versus Cont-TAC, whereas ketone and free fatty acid fractional contributions decreased. Additionally, protein posttranslational modifications by O-GlcNAc were significantly greater in Cont-TAC versus both Cont-Sham and MycKO-TAC. In conclusion, Myc alters substrate preferences for the citric acid cycle during early pressure overload hypertrophy without negatively affecting cardiac function. Myc also affects protein posttranslational modifications by O-GlcNAc during hypertrophy, which may regulate Myc-induced metabolic changes.

  11. Aortic aneurysm repair - endovascular

    Science.gov (United States)

    EVAR; Endovascular aneurysm repair - aorta; AAA repair - endovascular; Repair - aortic aneurysm - endovascular ... Endovascular aortic repair is done because your aneurysm is very large, growing quickly, or is leaking or bleeding. You may have ...

  12. Abdominal aortic aneurysm

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000162.htm Abdominal aortic aneurysm To use the sharing features on this page, ... blood to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs when an area of the aorta becomes ...

  13. Aortic growth rates in chronic aortic dissection

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, A.M. [Department of Radiology, Division of Thoracic Radiology, University of Michigan Medical Center (United States)]. E-mail: ainekell@med.umich.edu; Quint, L.E. [Department of Radiology, Division of Thoracic Radiology, University of Michigan Medical Center (United States); Nan, B. [School of Public Health, University of Michigan, Ann Arbor, Michigan (United States); Zheng, J. [School of Public Health, University of Michigan, Ann Arbor, Michigan (United States); Cronin, P. [Department of Radiology, Division of Thoracic Radiology, University of Michigan Medical Center (United States); Deeb, G.M. [Division of Cardiac Surgery, University of Michigan Medical Center (United States); Williams, D.M. [Division of Vascular Interventional Imaging, University of Michigan Medical Center (United States)

    2007-09-15

    Aim: To determine and compare rates of descending aortic enlargement and complications in chronic aortic dissection with and without a proximal aortic graft. Methods and materials: Fifty-two patients with dissection involving the descending aorta and who had undergone at least two computed tomography (CT) examinations at our institution between November, 1993 and February, 2004 were identified, including 24 non-operated patients (four type A, 20 type B) and 28 operated patients (type A). CT examinations per patient ranged from two to 10, and follow-up ranged from 1-123 months (mean 49 months, median 38.5 months). On each CT image, the aortic short axis (SA), false lumen (FL), and true lumen (TL) diameters were measured at the longitudinal midpoint of the dissection and at the point of maximum aortic diameter. Complications were tabulated, including aortic rupture and aortic enlargement requiring surgery. Results: For non-operated patients, the midpoint and maximum point SA, TL, and FL diameters increased significantly over time. For operated patients, the midpoint and maximum point SA and FL diameters increased significantly over time. In both groups, aortic enlargement was predominantly due to FL expansion. Diameter increases in non-operated patients were significantly larger than those in operated patients. The rate of change in aortic diameter was constant, regardless of aortic size. Four non-operated and six operated patients developed aortic complications. Conclusions: In patients with a dissection involving the descending thoracic aorta, the FL increased in diameter over time, at a constant rate, and to a greater degree in non-operated patients (mostly type B) compared with operated patients (all type A)

  14. Diffuse Supravalvular Aortic Stenosis: Surgical Repair in Adulthood

    Directory of Open Access Journals (Sweden)

    Giovanni Ferlan

    2009-01-01

    Full Text Available We present the case of a 54-year-old woman in which a diffuse congenital supravalvular aortic stenosis (SVAS was associated with a severe aortic valve incompetence and heavy calcification of the aortic annulus. Repair consisted in resection of the ascending aorta, patch augmentation of the hypoplastic aortic root and annulus, placement of a 20 mm Dacron tubular graft (Vascutek, Renfrewshire, UK and aortic valve replacement with a mechanical prosthesis (Sorin, Turin, Italy. Follow-up echocardiography demonstrated normal prosthetic valve function and a postoperative three-dimensional computed tomographic scan showed a normal shape of the reconstructed ascending aorta.

  15. AN ACCURATE MODELING OF DELAY AND SLEW METRICS FOR ON-CHIP VLSI RC INTERCONNECTS FOR RAMP INPUTS USING BURR’S DISTRIBUTION FUNCTION

    Directory of Open Access Journals (Sweden)

    Rajib Kar

    2010-09-01

    Full Text Available This work presents an accurate and efficient model to compute the delay and slew metric of on-chip interconnect of high speed CMOS circuits foe ramp input. Our metric assumption is based on the Burr’s Distribution function. The Burr’s distribution is used to characterize the normalized homogeneous portion of the step response. We used the PERI (Probability distribution function Extension for Ramp Inputs technique that extends delay metrics and slew metric for step inputs to the more general and realistic non-step inputs. The accuracy of our models is justified with the results compared with that of SPICE simulations.

  16. The functional upregulation of piriform cortex is associated with cross-modal plasticity in loss of whisker tactile inputs.

    Directory of Open Access Journals (Sweden)

    Bing Ye

    Full Text Available BACKGROUND: Cross-modal plasticity is characterized as the hypersensitivity of remaining modalities after a sensory function is lost in rodents, which ensures their awareness to environmental changes. Cellular and molecular mechanisms underlying cross-modal sensory plasticity remain unclear. We aim to study the role of different types of neurons in cross-modal plasticity. METHODOLOGY/PRINCIPAL FINDINGS: In addition to behavioral tasks in mice, whole-cell recordings at the excitatory and inhibitory neurons, and their two-photon imaging, were conducted in piriform cortex. We produced a mouse model of cross-modal sensory plasticity that olfactory function was upregulated by trimming whiskers to deprive their sensory inputs. In the meantime of olfactory hypersensitivity, pyramidal neurons and excitatory synapses were functionally upregulated, as well as GABAergic cells and inhibitory synapses were downregulated in piriform cortex from the mice of cross-modal sensory plasticity, compared with controls. A crosswire connection between barrel cortex and piriform cortex was established in cross-modal plasticity. CONCLUSION/SIGNIFICANCE: An upregulation of pyramidal neurons and a downregulation of GABAergic neurons strengthen the activities of neuronal networks in piriform cortex, which may be responsible for olfactory hypersensitivity after a loss of whisker tactile input. This finding provides the clues for developing therapeutic strategies to promote sensory recovery and substitution.

  17. Functional imaging of the human brainstem during somatosensory input and autonomic output

    Directory of Open Access Journals (Sweden)

    Luke Anthony Henderson

    2013-09-01

    Full Text Available Over the past half a century, many experimental animal investigations have explored the role of various brainstem regions in a variety of conditions. Despite the accumulation of a considerable body of knowledge in primarily anaesthetized preparations, relatively few investigations have explored brainstem function in awake humans. It is important that human brainstem function is explored given that many neurological conditions, from obstructive sleep apnea, chronic pain and hypertension, likely involve significant changes in the processing of information within the brainstem. Recent advances in the collection and processing of magnetic resonance images, has resulted in the possibility of exploring brainstem activity changes in awake healthy individuals and in those with various clinical conditions. We and others have begun to explore changes in brainstem activity in humans during a number of challenges, including during cutaneous and muscle pain, as well as during challenges that evoke increases in sympathetic activity. More recently we have successfully recorded sympathetic nerve activity concurrently with fMRI of the brainstem, which will allow us, for the first time to explore brainstem sites directly responsible for conditions such as hypertension. Since many conditions will involve changes in brainstem function and structure, defining brainstem changes will likely result in a greater ability to develop more effective treatment regimes.

  18. Alterations in alpha sub 1 - adrenoceptor function in rabbit aortic smooth muscle after long term administration of verapamil

    Energy Technology Data Exchange (ETDEWEB)

    Aceto, J.F.

    1988-01-01

    Aortic rings from naive rabbits and rabbits previously treated with large doses of verapamil for eight days were studied in vitro on day nine. Treated rings showed a decrease in norepinephrine potency and maximum developed isometric tension. Standard tissue bath analysis revealed a significant increase in the apparent dissociation constant of norepinephrine for the adrenoceptor which partly accounts for the decreased potency. Similar changes in potency and efficacy were found with other selected vasoconstrictors namely angiotensin, serotonin, and KCl. In contrast to the affinity change for norepinephrine, the alpha-adrenoceptor specific antagonist phentolamine revealed no change in adrenoceptor affinity after verapamil pretreatment. Further investigation using direct binding with {sup 125}I-labelled BE 2254, a high affinity alpha-adrenoceptor antagonist, showed only a slight decrease in the affinity of the pretreated tissues studied, thereby confirming that the main effect of chronic verapamil is peculiar to agonists.

  19. Multiple-function multi-input/multi-output digital control and on-line analysis

    Science.gov (United States)

    Hoadley, Sherwood T.; Wieseman, Carol D.; Mcgraw, Sandra M.

    1992-01-01

    The design and capabilities of two digital controller systems for aeroelastic wind-tunnel models are described. The first allowed control of flutter while performing roll maneuvers with wing load control as well as coordinating the acquisition, storage, and transfer of data for on-line analysis. This system, which employs several digital signal multi-processor (DSP) boards programmed in high-level software languages, is housed in a SUN Workstation environment. A second DCS provides a measure of wind-tunnel safety by functioning as a trip system during testing in the case of high model dynamic response or in case the first DCS fails. The second DCS uses National Instruments LabVIEW Software and Hardware within a Macintosh environment.

  20. Measurement of output power density from mobile phone as a function of input sound frequency.

    Science.gov (United States)

    Calabrò, Emanuele; Magazù, Salvatore

    2013-01-01

    Measurements of power density emitted by a mobile phone were carried out as a function of the sound frequency transmitted by a sound generator, ranging from 250 to 14000 Hz. Output power density was monitored by means of the selective radiation meter Narda SRM 3000 in spectrum analysis mode, and the octave frequency analysis of each tone used for the experimental design was acquired by the sound level meter Larson Davis LxT Wind. Vodafone providers were used for mobile phone calls with respect to various local base station in Southern-Italy. A relationship between the mobile phone microwaves power density and the sound frequencies transmitted by the sound generator was observed. In particular, microwaves power density level decreases significantly at sound frequency values larger than 4500 Hz. This result can be explained assuming that discontinuous transmission mode of global system for mobile communications is powered not only in silence-mode, but also at frequencies larger than 4500 Hz.

  1. Temporal dynamics of hot desert microbial communities reveal structural and functional responses to water input

    Science.gov (United States)

    Armstrong, Alacia; Valverde, Angel; Ramond, Jean-Baptiste; Makhalanyane, Thulani P.; Jansson, Janet K.; Hopkins, David W.; Aspray, Thomas J.; Seely, Mary; Trindade, Marla I.; Cowan, Don A.

    2016-01-01

    The temporal dynamics of desert soil microbial communities are poorly understood. Given the implications for ecosystem functioning under a global change scenario, a better understanding of desert microbial community stability is crucial. Here, we sampled soils in the central Namib Desert on sixteen different occasions over a one-year period. Using Illumina-based amplicon sequencing of the 16S rRNA gene, we found that α-diversity (richness) was more variable at a given sampling date (spatial variability) than over the course of one year (temporal variability). Community composition remained essentially unchanged across the first 10 months, indicating that spatial sampling might be more important than temporal sampling when assessing β-diversity patterns in desert soils. However, a major shift in microbial community composition was found following a single precipitation event. This shift in composition was associated with a rapid increase in CO2 respiration and productivity, supporting the view that desert soil microbial communities respond rapidly to re-wetting and that this response may be the result of both taxon-specific selection and changes in the availability or accessibility of organic substrates. Recovery to quasi pre-disturbance community composition was achieved within one month after rainfall. PMID:27680878

  2. Experimental study on aortic remodeling in sinoaortic denervated rats

    Institute of Scientific and Technical Information of China (English)

    MIAO Chao-yu; TAO Xia; GUAN Yun-feng; YANG You-cai; CHU Zheng-xu; SU Ding-feng

    2001-01-01

    Objective: To study the aortic remodeling produced by chronic sinoaortic denervation (SAD) and its time course, and to study the role of humoral factor in the SAD-induced aortic remodeling. Methods: In rats with chronic SAD or sham operation, the aortic structure was measured by computer-assisted image analysis, the aortic function by isolated artery preparation, and angiotensin Ⅱ concentration by radioimmunoassay. Results and Conclusion: The aortic structural remodeling developed progressively at 4, 8, 16 and 32 weeks after SAD. Aortic structural remodeling after SAD expressed mainly as aortic hypertrophy due to SMC growth and collagen accumulation. The aortic contraction elicited by norepinephrine (NE) was progressively increased 8, 16 and 32 weeks after SAD. The aortic relaxation elicited by acetylcholine (ACh) was depressed 8, 16 and 32 weeks after SAD. In addition, in 32-week SAD rats the NE-induced contraction was not increased by endothelial denudation. These indicated that the increased contraction and depressed relaxation after SAD were related to the change of endothelium and/or the change of interaction between endothelium and SMC. In 10-week SAD rats, plasma angiotensin Ⅱ concentration remained unchanged, whereas aortic angiotensin Ⅱ concentration was significantly increased, suggesting that activation of tissue renin-angiotensin system may be involved in SAD-induced aortic remodeling.

  3. File list: InP.CDV.05.AllAg.Aortic_valve_endothelial_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.CDV.05.AllAg.Aortic_valve_endothelial_cells hg19 Input control Cardiovascular Aortic valve endothelial... cells SRX285598 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/InP.CDV.05.AllAg.Aortic_valve_endothelial_cells.bed ...

  4. File list: InP.CDV.50.AllAg.Aortic_valve_endothelial_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.CDV.50.AllAg.Aortic_valve_endothelial_cells hg19 Input control Cardiovascular Aortic valve endothelial... cells SRX285598 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/InP.CDV.50.AllAg.Aortic_valve_endothelial_cells.bed ...

  5. File list: InP.CDV.10.AllAg.Aortic_valve_endothelial_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.CDV.10.AllAg.Aortic_valve_endothelial_cells hg19 Input control Cardiovascular Aortic valve endothelial... cells SRX285598 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/InP.CDV.10.AllAg.Aortic_valve_endothelial_cells.bed ...

  6. File list: InP.CDV.20.AllAg.Aortic_valve_endothelial_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.CDV.20.AllAg.Aortic_valve_endothelial_cells hg19 Input control Cardiovascular Aortic valve endothe...lial cells SRX285598 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/InP.CDV.20.AllAg.Aortic_valve_endothelial_cells.bed ...

  7. Aortic stiffness is related to left ventricular diastolic function in patients with diabetes mellitus type 1: assessment with MRI and speckle tracking strain analysis

    NARCIS (Netherlands)

    Schinkel, L.D. van; Auger, D.; Elderen, S.G. van; Ajmone Marsan, N.; Delgado, V.; Lamb, H.J.; Ng, A.C.; Smit, J.W.A.; Bax, J.J.; Westenberg, J.J.; Roos, A. de

    2013-01-01

    Diabetes mellitus type 1 (DM1) is associated with aortic stiffening and left ventricular (LV) diastolic dysfunction, however the relationship between aortic stiffness and LV diastolic dysfunction in DM1 patients is still largely unknown. The purpose of this study was to evaluate whether an increased

  8. Supravalvular aortic stenosis in adult with anomalies of aortic arch vessels and aortic regurgitation

    Science.gov (United States)

    Valente, Acrisio Sales; Alencar, Polyanna; Santos, Alana Neiva; Lobo, Roberto Augusto de Mesquita; de Mesquita, Fernando Antônio; Guimarães, Aloyra Guedis

    2013-01-01

    The supravalvular aortic stenosis is a rare congenital heart defect being very uncommon in adults. We present a case of supravalvular aortic stenosis in adult associated with anomalies of the aortic arch vessels and aortic regurgitation, which was submitted to aortic valve replacement and arterioplasty of the ascending aorta with a good postoperative course. PMID:24598962

  9. Prophylactic aortic root surgery in patients with Marfan syndrome : 10 years' experience with a protocol based on body surface area

    NARCIS (Netherlands)

    Aalberts, Jan J. J.; van Tintelen, J. Peter; Hillege, Hans L.; Boonstra, Piet W.; van den Berg, Maarten P.; Waterbolk, T

    2008-01-01

    Background: Current guidelines recommending prophylactic aortic root replacement in Marfan syndrome are based on absolute diameters of the aortic root. However, aortic root diameter is a function of body surface area (BSA). Here, we report our experience with a protocol for prophylactic aortic root

  10. Preliminary evaluation of MRI-derived input function for quantitative measurement of glucose metabolism in an integrated PET-MRI

    Energy Technology Data Exchange (ETDEWEB)

    Anazodo, Udunna; Kewin, Matthew [Lawson Health Research Institute, Department of Medical Biophysics, Western University, London, Ontario (Canada); Finger, Elizabeth [Department of Clinical Neurological Sciences, Western University, London, Ontario (Canada); Thiessen, Jonathan; Hadway, Jennifer; Butler, John [Lawson Health Research Institute, Department of Medical Biophysics, Western University, London, Ontario (Canada); Pavlosky, William [Diagnostic Imaging, St Joseph' s Health Care, London, Ontario (Canada); Prato, Frank; Thompson, Terry; St Lawrence, Keith [Lawson Health Research Institute, Department of Medical Biophysics, Western University, London, Ontario (Canada)

    2015-05-18

    PET semi-quantitative methods such as relative uptake value can be robust but offer no biological information and do not account for intra-subject variability in tracer administration or clearance. Simultaneous multimodal measurements that combine PET and MRI not only permit crucial multiparametric measurements, it provides means of applying tracer kinetic modelling without the need for serial arterial blood sampling. In this study we adapted an image-derived input function (IDIF) method to improve characterization of glucose metabolism in an ongoing dementia study. Here we present preliminary results in a small group of frontotemporal dementia patients and controls. IDIF was obtained directly from dynamic PET data guided by regions of interest drawn on carotid vessels on high resolution T1-weighted MR Images. IDIF was corrected for contamination of non-arterial voxels. A validation of the method was performed in a porcine model in a PET-CT scanner comparing IDIF to direct arterial blood samples. Metabolic rate of glucose (CMRglc) was measured voxel-by-voxel in gray matter producing maps that were compared between groups. Net influx rate (Ki) and global mean CMRglc are reported. A good correlation (r = 0.9 p<0.0001) was found between corrected IDIF and input function measured from direct arterial blood sampling in the validation study. In 3 FTD and 3 controls, a trend towards hypometabolism was found in frontal, temporal and parietal lobes similar to significant differences previously reported by other groups. The global mean CMRglc and Ki observed in control subjects are in line with previous reports. In general, kinetic modelling of PET-FDG using an MR-IDIF can improve characterization of glucose metabolism in dementia. This method is feasible in multimodal studies that aim to combine PET molecular imaging with MRI as dynamic PET can be acquired along with multiple MRI measurements.

  11. Investigation of dynamic SPECT measurements of the arterial input function in human subjects using simulation, phantom and human studies

    Science.gov (United States)

    Winant, Celeste D.; Aparici, Carina Mari; Zelnik, Yuval R.; Reutter, Bryan W.; Sitek, Arkadiusz; Bacharach, Stephen L.; Gullberg, Grant T.

    2012-01-01

    Computer simulations, a phantom study and a human study were performed to determine whether a slowly rotating single-photon computed emission tomography (SPECT) system could provide accurate arterial input functions for quantification of myocardial perfusion imaging using kinetic models. The errors induced by data inconsistency associated with imaging with slow camera rotation during tracer injection were evaluated with an approach called SPECT/P (dynamic SPECT from positron emission tomography (PET)) and SPECT/D (dynamic SPECT from database of SPECT phantom projections). SPECT/P simulated SPECT-like dynamic projections using reprojections of reconstructed dynamic 94Tc-methoxyisobutylisonitrile (94Tc-MIBI) PET images acquired in three human subjects (1 min infusion). This approach was used to evaluate the accuracy of estimating myocardial wash-in rate parameters K1 for rotation speeds providing 180° of projection data every 27 or 54 s. Blood input and myocardium tissue time-activity curves (TACs) were estimated using spatiotemporal splines. These were fit to a one-compartment perfusion model to obtain wash-in rate parameters K1. For the second method (SPECT/D), an anthropomorphic cardiac torso phantom was used to create real SPECT dynamic projection data of a tracer distribution derived from 94Tc-MIBI PET scans in the blood pool, myocardium, liver and background. This method introduced attenuation, collimation and scatter into the modeling of dynamic SPECT projections. Both approaches were used to evaluate the accuracy of estimating myocardial wash-in parameters for rotation speeds providing 180° of projection data every 27 and 54 s. Dynamic cardiac SPECT was also performed in a human subject at rest using a hybrid SPECT/CT scanner. Dynamic measurements of 99mTc-tetrofosmin in the myocardium were obtained using an infusion time of 2 min. Blood input, myocardium tissue and liver TACs were estimated using the same spatiotemporal splines. The spatiotemporal maximum

  12. Investigation of dynamic SPECT measurements of the arterial input function in human subjects using simulation, phantom and human studies.

    Science.gov (United States)

    Winant, Celeste D; Aparici, Carina Mari; Zelnik, Yuval R; Reutter, Bryan W; Sitek, Arkadiusz; Bacharach, Stephen L; Gullberg, Grant T

    2012-01-21

    Computer simulations, a phantom study and a human study were performed to determine whether a slowly rotating single-photon computed emission tomography (SPECT) system could provide accurate arterial input functions for quantification of myocardial perfusion imaging using kinetic models. The errors induced by data inconsistency associated with imaging with slow camera rotation during tracer injection were evaluated with an approach called SPECT/P (dynamic SPECT from positron emission tomography (PET)) and SPECT/D (dynamic SPECT from database of SPECT phantom projections). SPECT/P simulated SPECT-like dynamic projections using reprojections of reconstructed dynamic (94)Tc-methoxyisobutylisonitrile ((94)Tc-MIBI) PET images acquired in three human subjects (1 min infusion). This approach was used to evaluate the accuracy of estimating myocardial wash-in rate parameters K(1) for rotation speeds providing 180° of projection data every 27 or 54 s. Blood input and myocardium tissue time-activity curves (TACs) were estimated using spatiotemporal splines. These were fit to a one-compartment perfusion model to obtain wash-in rate parameters K(1). For the second method (SPECT/D), an anthropomorphic cardiac torso phantom was used to create real SPECT dynamic projection data of a tracer distribution derived from (94)Tc-MIBI PET scans in the blood pool, myocardium, liver and background. This method introduced attenuation, collimation and scatter into the modeling of dynamic SPECT projections. Both approaches were used to evaluate the accuracy of estimating myocardial wash-in parameters for rotation speeds providing 180° of projection data every 27 and 54 s. Dynamic cardiac SPECT was also performed in a human subject at rest using a hybrid SPECT/CT scanner. Dynamic measurements of (99m)Tc-tetrofosmin in the myocardium were obtained using an infusion time of 2 min. Blood input, myocardium tissue and liver TACs were estimated using the same spatiotemporal splines. The

  13. Fully automated calculation of image-derived input function in simultaneous PET/MRI in a sheep model

    Energy Technology Data Exchange (ETDEWEB)

    Jochimsen, Thies H.; Zeisig, Vilia [Department of Nuclear Medicine, Leipzig University Hospital, Liebigstr. 18, Leipzig (Germany); Schulz, Jessica [Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstr. 1a, Leipzig, D-04103 (Germany); Werner, Peter; Patt, Marianne; Patt, Jörg [Department of Nuclear Medicine, Leipzig University Hospital, Liebigstr. 18, Leipzig (Germany); Dreyer, Antje Y. [Fraunhofer Institute of Cell Therapy and Immunology, Perlickstr. 1, Leipzig, D-04103 (Germany); Translational Centre for Regenerative Medicine, University Leipzig, Philipp-Rosenthal-Str. 55, Leipzig, D-04103 (Germany); Boltze, Johannes [Fraunhofer Institute of Cell Therapy and Immunology, Perlickstr. 1, Leipzig, D-04103 (Germany); Translational Centre for Regenerative Medicine, University Leipzig, Philipp-Rosenthal-Str. 55, Leipzig, D-04103 (Germany); Fraunhofer Research Institution of Marine Biotechnology and Institute for Medical and Marine Biotechnology, University of Lübeck, Lübeck (Germany); Barthel, Henryk; Sabri, Osama; Sattler, Bernhard [Department of Nuclear Medicine, Leipzig University Hospital, Liebigstr. 18, Leipzig (Germany)

    2016-02-13

    Obtaining the arterial input function (AIF) from image data in dynamic positron emission tomography (PET) examinations is a non-invasive alternative to arterial blood sampling. In simultaneous PET/magnetic resonance imaging (PET/MRI), high-resolution MRI angiographies can be used to define major arteries for correction of partial-volume effects (PVE) and point spread function (PSF) response in the PET data. The present study describes a fully automated method to obtain the image-derived input function (IDIF) in PET/MRI. Results are compared to those obtained by arterial blood sampling. To segment the trunk of the major arteries in the neck, a high-resolution time-of-flight MRI angiography was postprocessed by a vessel-enhancement filter based on the inertia tensor. Together with the measured PSF of the PET subsystem, the arterial mask was used for geometrical deconvolution, yielding the time-resolved activity concentration averaged over a major artery. The method was compared to manual arterial blood sampling at the hind leg of 21 sheep (animal stroke model) during measurement of blood flow with O15-water. Absolute quantification of activity concentration was compared after bolus passage during steady state, i.e., between 2.5- and 5-min post injection. Cerebral blood flow (CBF) values from blood sampling and IDIF were also compared. The cross-calibration factor obtained by comparing activity concentrations in blood samples and IDIF during steady state is 0.98 ± 0.10. In all examinations, the IDIF provided a much earlier and sharper bolus peak than in the time course of activity concentration obtained by arterial blood sampling. CBF using the IDIF was 22 % higher than CBF obtained by using the AIF yielded by blood sampling. The small deviation between arterial blood sampling and IDIF during steady state indicates that correction of PVE and PSF is possible with the method presented. The differences in bolus dynamics and, hence, CBF values can be explained by the

  14. Tissue Velocities and Myocardial Deformation in Asymptomatic and Symptomatic Aortic Stenosis

    DEFF Research Database (Denmark)

    Carstensen, Helle Gervig; Larsen, Linnea Hornbech; Hassager, Christian

    2015-01-01

    BACKGROUND: Assessment of myocardial longitudinal function has proved to be a sensitive marker of deteriorating myocardial function in aortic stenosis, demonstrated by both color Doppler tissue imaging and recently by two-dimensional speckle-tracking echocardiography. The aim of this study...... was to compare velocity (color Doppler tissue imaging) and deformation (two-dimensional speckle-tracking echocardiography) in relation to global and regional longitudinal function in asymptomatic and severe symptomatic aortic stenosis. METHODS: In a cross-sectional design, 231 patients with aortic stenosis were...... divided into four groups: asymptomatic moderate aortic stenosis (aortic valve area, 1.0-1.5 cm(2); n = 38), asymptomatic severe aortic stenosis (aortic valve area aortic stenosis with preserved (n = 68) and reduced (

  15. Automatic determination of the arterial input function in dynamic susceptibility contrast MRI: comparison of different reproducible clustering algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Jiandong; Yang, Jiawen; Guo, Qiyong [Shengjing Hospital of China Medical University, Department of Radiology, Shenyang (China)

    2015-05-01

    Arterial input function (AIF) plays an important role in the quantification of cerebral hemodynamics. The purpose of this study was to select the best reproducible clustering method for AIF detection by comparing three algorithms reported previously in terms of detection accuracy and computational complexity. First, three reproducible clustering methods, normalized cut (Ncut), hierarchy (HIER), and fast affine propagation (FastAP), were applied independently to simulated data which contained the true AIF. Next, a clinical verification was performed where 42 subjects participated in dynamic susceptibility contrast MRI (DSC-MRI) scanning. The manual AIF and AIFs based on the different algorithms were obtained. The performance of each algorithm was evaluated based on shape parameters of the estimated AIFs and the true or manual AIF. Moreover, the execution time of each algorithm was recorded to determine the algorithm that operated more rapidly in clinical practice. In terms of the detection accuracy, Ncut and HIER method produced similar AIF detection results, which were closer to the expected AIF and more accurate than those obtained using FastAP method; in terms of the computational efficiency, the Ncut method required the shortest execution time. Ncut clustering appears promising because it facilitates the automatic and robust determination of AIF with high accuracy and efficiency. (orig.)

  16. Therapeutics Targeting Drivers of Thoracic Aortic Aneurysms and Acute Aortic Dissections: Insights from Predisposing Genes and Mouse Models.

    Science.gov (United States)

    Milewicz, Dianna M; Prakash, Siddharth K; Ramirez, Francesco

    2017-01-14

    Thoracic aortic diseases, including aneurysms and dissections of the thoracic aorta, are a major cause of morbidity and mortality. Risk factors for thoracic aortic disease include increased hemodynamic forces on the ascending aorta, typically due to poorly controlled hypertension, and heritable genetic variants. The altered genes predisposing to thoracic aortic disease either disrupt smooth muscle cell (SMC) contraction or adherence to an impaired extracellular matrix, or decrease canonical transforming growth factor beta (TGF-β) signaling. Paradoxically, TGF-β hyperactivity has been postulated to be the primary driver for the disease. More recently, it has been proposed that the response of aortic SMCs to the hemodynamic load on a structurally defective aorta is the primary driver of thoracic aortic disease, and that TGF-β overactivity in diseased aortas is a secondary, unproductive response to restore tissue function. The engineering of mouse models of inherited aortopathies has identified potential therapeutic agents to prevent thoracic aortic disease.

  17. Optimisation of vascular input and output functions in CT-perfusion imaging using 256(or more)-slice multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Niesten, Joris M.; Schaaf, Irene C. van der; Riordan, Alan J.; Jong, Hugo W.A.M. de; Mali, Willem P.T.M.; Velthuis, Birgitta K. [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands)

    2013-05-15

    To evaluate the accuracy and reproducibility of CT-perfusion (CTP) by finding the optimal artery for the arterial input function (AIF) and re-evaluating the necessity of the venous output function (VOF). Forty-four acute ischaemic stroke patients who underwent non-enhanced CT, CTP and CT-angiography using 256-slice multidetector computed tomography (MDCT) were evaluated. The anterior cerebral artery (ACA), middle cerebral artery (MCA), internal carotid artery (ICA) and basilar artery were selected as the AIF. Subsequently the resulting area under the time-enhancement curve of the AIF (AUC{sub AIF}) and quantitative perfusion measurements were analysed by repeated measures ANOVA and subsequently the paired t test. To evaluate reproducibility we examined if the VOF could be deleted by comparing the perfusion measurements using versus not using the VOF (paired t test). The AUC{sub AIF} and perfusion measurements resulting from the different AIFs showed significant group differences (all P < 0.0001). The ICA had the largest AUC{sub AIF} and resulted in the highest mean transient time (MTT) and lowest cerebral blood flow (CBF), whereas the basilar artery showed the lowest cerebral blood volume (CBV). Not using the VOF showed significantly higher CBV and CBF in 66 % of patients on the ipsilateral (P < 0.0001 and P = 0.007, respectively) and contralateral hemisphere (P < 0.0001 and P = 0.019, respectively). Selecting the ICA as the AIF and continuing the use of the VOF would improve the accuracy of CTP. (orig.)

  18. MFAP5 loss-of-function mutations underscore the involvement of matrix alteration in the pathogenesis of familial thoracic aortic aneurysms and dissections.

    Science.gov (United States)

    Barbier, Mathieu; Gross, Marie-Sylvie; Aubart, Mélodie; Hanna, Nadine; Kessler, Ketty; Guo, Dong-Chuan; Tosolini, Laurent; Ho-Tin-Noe, Benoit; Regalado, Ellen; Varret, Mathilde; Abifadel, Marianne; Milleron, Olivier; Odent, Sylvie; Dupuis-Girod, Sophie; Faivre, Laurence; Edouard, Thomas; Dulac, Yves; Busa, Tiffany; Gouya, Laurent; Milewicz, Dianna M; Jondeau, Guillaume; Boileau, Catherine

    2014-12-04

    Thoracic aortic aneurysm and dissection (TAAD) is an autosomal-dominant disorder with major life-threatening complications. The disease displays great genetic heterogeneity with some forms allelic to Marfan and Loeys-Dietz syndrome, and an important number of cases still remain unexplained at the molecular level. Through whole-exome sequencing of affected members in a large TAAD-affected family, we identified the c.472C>T (p.Arg158(∗)) nonsense mutation in MFAP5 encoding the extracellular matrix component MAGP-2. This protein interacts with elastin fibers and the microfibrillar network. Mutation screening of 403 additional probands identified an additional missense mutation of MFAP5 (c.62G>T [p.Trp21Leu]) segregating with the disease in a second family. Functional analyses performed on both affected individual's cells and in vitro models showed that these two mutations caused pure or partial haploinsufficiency. Thus, alteration of MAGP-2, a component of microfibrils and elastic fibers, appears as an initiating mechanism of inherited TAAD.

  19. Mitral valve repair is not always needed in patients with functional mitral regurgitation undergoing coronary artery bypass grafting and/or aortic valve replacement

    Science.gov (United States)

    Lindeboom, J.E.; Jaarsma, W.; Kelder, J.C.; Morshuis, W.J.; Visser, C.A.

    2005-01-01

    Background and aim Functional mitral regurgitation (FMR) is defined as mitral regurgitation in the absence of intrinsic valvular abnormalities. We prospectively evaluated the effect of coronary artery bypass grafting (CABG) and/or aortic valve replacement (AVR), without additional mitral valve repair, on the degree of moderate or severe FMR. Study design and methods From a cohort of 2829 patients undergoing CABG and/or AVR in the St. Antonius Hospital, 67 patients were identified with moderate or severe FMR by transthoracic and transoesophageal Doppler echocardiography. Results Two out of the 67 patients (3%) died perioperatively. During follow-up (3-18 months) mitral regurgitation decreased by one grade in 29 patients, by two grades in 28, by three grades in five patients and remained unchanged in one patient (p=0.0001). Of all patients, 85% had grade I mitral regurgitation or less. Grade II mitral regurgitation remained in nine patients with a previous large myocardial infarction and/or annular calcifications. NYHA class improved from 3.1+0.5 to 1.4+0.4 (p=0.0001). Ejection fraction increased from 46 to 55% (p=0.0001). Overall, left atrial and left ventricular end-diastolic dimensions decreased significantly. In contrast, no decrease in dimensions was seen in patients with postoperative grade II mitral regurgitation. Conclusion FMR may improve significantly following CABG and/or AVR, although a previous large myocardial infarction and/or annular calcifications may affect outcome. PMID:25696484

  20. Influence of the aortic valve leaflets on the fluid-dynamics in aorta in presence of a normally functioning bicuspid valve.

    Science.gov (United States)

    Bonomi, D; Vergara, C; Faggiano, E; Stevanella, M; Conti, C; Redaelli, A; Puppini, G; Faggian, G; Formaggia, L; Luciani, G B

    2015-11-01

    In this work, we consider the blood fluid-dynamics in the ascending aorta in presence of a normally functioning bicuspid aortic valve (BAV). In particular, we perform an unsteady finite element study in real geometries with physiological velocity boundary conditions at the inlet to assess the effect of the inclusion of the leaflets on the fluid-dynamic abnormalities characterizing BAV cases. To this aim, we perform a comparison in two geometries (a dilated and a non-dilated ones) among three scenarios which are built up for each geometry: BAV without leaflets, BAV with leaflets, and tricuspid case with leaflets. For each case, we compute four indices quantifying flow asymmetry, reversal flows, helical patterns, and wall shear stresses. Our results show that the inclusion of the leaflets increases the fluid-dynamics abnormalities, especially for the non-dilated configuration, which presents a greater increment of the indices. In particular, we observe that the values of the time-averaged wall shear stress and of the systolic jet asymmetry increase by approximatively 100 and 40%, respectively, when considering the leaflets.

  1. Function and role of voltage-gated sodium channel NaV1.7 expressed in aortic smooth muscle cells.

    Science.gov (United States)

    Meguro, Kentaro; Iida, Haruko; Takano, Haruhito; Morita, Toshihiro; Sata, Masataka; Nagai, Ryozo; Nakajima, Toshiaki

    2009-01-01

    Voltage-gated Na(+) channel currents (I(Na)) are expressed in several types of smooth muscle cells. The purpose of this study was to evaluate the expression of I(Na), its functional role, pathophysiology in cultured human (hASMCs) and rabbit aortic smooth muscle cells (rASMCs), and its association with vascular intimal hyperplasia. In whole cell voltage clamp, I(Na) was observed at potential positive to -40 mV, was blocked by tetrodotoxin (TTX), and replacing extracellular Na(+) with N-methyl-d-glucamine in cultured hASMCs. In contrast to native aorta, cultured hASMCs strongly expressed SCN9A encoding Na(V)1.7, as determined by quantitative RT-PCR. I(Na) was abolished by the treatment with SCN9A small-interfering (si)RNA (P SCN9A siRNA significantly inhibited cell migration (P SCN9A in cultured rASMCs and aorta 48 h after balloon injury but not in native aorta. In conclusion, these studies show that I(Na) is expressed in cultured and diseased conditions but not in normal aorta. The Na(V)1.7 plays an important role in cell migration, endocytosis, and secretion. Na(V)1.7 is also expressed in aorta after balloon injury, suggesting a potential role for Na(V)1.7 in the progression of intimal hyperplasia.

  2. Aortic annulus eccentricity before and after transcatheter aortic valve implantation: Comparison of balloon-expandable and self-expanding prostheses

    Energy Technology Data Exchange (ETDEWEB)

    Schuhbaeck, Annika, E-mail: annika.schuhbaeck@uk-erlangen.de [Department of Cardiology, University of Erlangen, Erlangen (Germany); Weingartner, Christina [Department of Cardiology, University of Gießen, Giessen (Germany); Arnold, Martin; Schmid, Jasmin; Pflederer, Tobias; Marwan, Mohamed [Department of Cardiology, University of Erlangen, Erlangen (Germany); Rixe, Johannes; Nef, Holger [Department of Cardiology, University of Gießen, Giessen (Germany); Schneider, Christian [Department of Radiology, University of Gießen, Giessen (Germany); Lell, Michael; Uder, Michael [Department of Radiology, University of Erlangen, Erlangen (Germany); Ensminger, Stephan [Department of Thoracic and Cardiovascular Surgery, Heart and Diabetes Center NRW, Ruhr-University Bochum, Bad Oeynhausen (Germany); Feyrer, Richard; Weyand, Michael [Department of Cardiothoracic Surgery, University of Erlangen, Erlangen (Germany); Achenbach, Stephan [Department of Cardiology, University of Erlangen, Erlangen (Germany)

    2015-07-15

    Highlights: • Post-implant geometry of catheter-based aortic valve prostheses is influenced by aortic valve calcification. • Balloon-expandable prostheses are more circular as compared to self-expanding prostheses. • The impact of post-implant geometry on valve function needs to be investigated. - Abstract: Introduction: The geometry of the aortic annulus and implanted transcatheter aortic valve prosthesis might influence valve function. We investigated the influence of valve type and aortic valve calcification on post-implant geometry of catheter-based aortic valve prostheses. Methods: Eighty consecutive patients with severe aortic valve stenosis (mean age 82 ± 6 years) underwent computed tomography before and after TAVI. Aortic annulus diameters were determined. Influence of prosthesis type and degree of aortic valve calcification on post-implant eccentricity were analysed. Results: Aortic annulus eccentricity was reduced in patients after TAVI (0.21 ± 0.06 vs. 0.08 ± 0.06, p < 0.0001). Post-TAVI eccentricity was significantly lower in 65 patients following implantation of a balloon-expandable prosthesis as compared to 15 patients who received a self-expanding prosthesis (0.06 ± 0.05 vs. 0.15 ± 0.07, p < 0.0001), even though the extent of aortic valve calcification was not different. After TAVI, patients with a higher calcium amount retained a significantly higher eccentricity compared to patients with lower amounts of calcium. Conclusions: Patients undergoing TAVI with a balloon-expandable prosthesis show a more circular shape of the implanted prosthesis as compared to patients with a self-expanding prosthesis. Eccentricity of the deployed prosthesis is affected by the extent of aortic valve calcification.

  3. Estimation of an image derived input function with MR-defined carotid arteries in FDG-PET human studies using a novel partial volume correction method

    DEFF Research Database (Denmark)

    Sari, Hasan; Erlandsson, Kjell; Law, Ian

    2017-01-01

    Kinetic analysis of (18)F-fluorodeoxyglucose positron emission tomography data requires an accurate knowledge the arterial input function. The gold standard method to measure the arterial input function requires collection of arterial blood samples and is an invasive method. Measuring an image...... segmentation of the carotid arteries from MR images. The simulation study results showed that at least 92% of the true intensity could be recovered after the partial volume correction. Results from 19 subjects showed that the mean cerebral metabolic rate of glucose calculated using arterial samples and partial...... volume corrected image derived input function were 26.9 and 25.4 mg/min/100 g, respectively, for the grey matter and 7.2 and 6.7 mg/min/100 g for the white matter. No significant difference in the estimated cerebral metabolic rate of glucose values was observed between arterial samples and corrected...

  4. Awake transapical aortic valve implantation using thoracic epidural anesthesia.

    Science.gov (United States)

    Mukherjee, Chirojit; Walther, Thomas; Borger, Michael Andrew; Kempfert, Joerg; Schuler, Gerhard; Mohr, Friedrich Wilhelm; Ender, Joerg

    2009-09-01

    Transapical aortic valve implantation is a minimally invasive, beating-heart procedure that normally requires a general anesthetic. We herein report an 85-year-old patient with impaired pulmonary function who underwent successful transapical aortic valve implantation while awake, using a thoracic epidural anesthetic.

  5. Incidental necropsy finding of a quadricuspid aortic valve

    NARCIS (Netherlands)

    van Rijswijk, Jan Willem; Willemink, Martin; Kluin, Jolanda; Vink, Aryan

    2015-01-01

    Quadricuspid aortic valve is a rare congenital cardiac malformation often associated with abnormal valve function. In this article, we present a case of quadricuspid aortic valve only diagnosed at the time of post-mortem examination. (C) 2015 Elsevier Inc. All rights reserved.

  6. Relation between Fresnel transform of input light field and the two-parameter Radon transform of Wigner function of the field

    Institute of Scientific and Technical Information of China (English)

    Fan Hong-Yi; Hu Li-Yun

    2009-01-01

    This paper proves a new theorem on the relationship between optical field Wigner function's two-parameter Radon transform and optical Fresnel transform of the field, I.e., when an input field ψ(x') propagates through an optical [D (-B) (-C) A] system, the energy density of the output field is equal to the Radon transform of the Wigner function of the input field, where the Radon transform parameters are D, B. It prove this theorem in both spatial-domain and frequency-domain, in the latter case the Radon transform parameters are A, C 7.

  7. The Effects of Fetuin-A Levels on Aortic Stenosis

    Directory of Open Access Journals (Sweden)

    Ahmet Tutuncu

    2014-12-01

    Full Text Available Aim: We aimed to investigate the relation between fetuin-A and calcific aortic stenosis in non diabetic patients whose renal function were normal. Material and Method: 26 patients followed for aortic stenosis by our cardiology clinic for outpatients and 25 voluntary healthy subjects were included in the study. The fetuin%u2013A levels were measured from the venous blood samples of the study population. All patients underwent transthorasic echocardiography, the aortic valvular area and left ventricular parameters of the patients were measured. Results: The average age of the patients in degenerative aortic stenosis group was significantly higher than the control group. The parameters related to aortic valve were naturally higher in patients with dejenerative aortic valve. There was no siginificant difference between two groups about fetuin-A levels. Further more there was no significant relation between fetuin-a levels and aortic stenosis severity. Discussion: In conclusion fetuin-A is a multifunctional glycoprotein that plays important role in systemic calcification inhibition and valvular calcification. Finally aortic stenosis is an active process and larger studies that investigate the relation between fetuin-a and the progression and prognosis of aortic stenosis are needed.

  8. Structural and functional effects of conventional and low pesticide input crop-protection programs on benthic macroinvertebrate communities in outdoor pond mesocosms.

    Science.gov (United States)

    Auber, Arnaud; Roucaute, Marc; Togola, Anne; Caquet, Thierry

    2011-11-01

    The impacts of current and alternative wheat crop protection programs were compared in outdoor pond mesocosms in a 10-month long study. Realistic exposure scenarios were built based upon the results of modelling of drift, drainage and runoff of pesticides successively applied under two environmental situations characteristics of drained soils of northern France. Each situation was associated to two crop protection programs ("Conventional" and "Low-input") differing in the nature of pesticides used, number of treatments and application rate. Both programs induced significant direct negative effects on various invertebrate groups. Bifenthrin and cyprodynil were identified as the main responsible for these effects in conventional and low-input program, respectively. Indirect effects were also demonstrated especially following treatments with cyprodynil. Litter breakdown was significantly reduced in all treated mesocosms as the functional consequence of the decrease in the abundance of shredders (asellids, Gammarus pulex) illustrating the link between structural and functional effects of pesticides on macroinvertebrate communities. Recovery was observed for many taxa before the end of the study but not for the most sensitive non mobile taxa such as G. pulex. No influence of the agropedoclimatic situation on the effects was shown, suggesting than the main impacts were associated to inputs from drift. The results confirm that the proposed low-input program was less hazardous than the conventional program but the observed structural and functional impact of the low-input program suggest that further improvement of alternative crop protection programs is still needed.

  9. 瓣膜类型对主动脉瓣置换术后早期心功能影响的分析%Analysis of Valve Type Impact on Early Heart Function after Aortic Valve Replacement

    Institute of Scientific and Technical Information of China (English)

    闫成雷; 高长青; 李伯君; 叶卫华

    2012-01-01

    目的 分析主动脉瓣置换术后瓣膜类型对患者术后早期心功能的影响.方法 回顾性分析在我科行主动脉瓣置换手术的68例患者,年龄23 ~73(48.9±11.2)岁,其中男54例,女14例.病变类型:单纯主动脉瓣狭窄5例,主动脉瓣狭窄伴关闭不全21例,单纯主动脉瓣关闭不全42例.其中53例植入机械瓣,15例植入生物瓣.结果 无死亡及其他严重并发症.术后超声心动图示升主动脉内径[(37.9±5.3) vs (40.5±5.7) mm,P<0.05]较术前明显减小,术后左心室舒张末内径[(46.2±9.1) vs (58.9±11.6) mm,P<0.05]较术前明显减小,生物瓣及机械瓣两组患者术前及术后左心室舒张末内径、左心室射血分数、升主动脉直径等比较,差异无统计学意义,左心室舒张末内径和升主动脉直径的术前及术后的变化值比较,差异无统计学意义.结论 主动脉瓣置换术可改善患者心功能,瓣膜的类型在主动脉瓣置换术中对心功能的改善无影响.%Objective To analyze the impact of valve type on early heart function after aortic valve replacement. Methods We retrospectively analyzed 68 patients who underwent aortic valve replacement. Patients were aged (48.9±11.2) years on average ( range ,23 to 73 years ), including 54 males and 14 females. 5 patients had pure aortic stenosis,21 patients pure aortic insufficiency,and 42 patients aortic stenosis with insufficiency. Among them,53 underwent mechanical valve replacement,and 15 underwent bioprosthetic valve replacement. Results No death or other serious complications. The postoperative ascending aortic di-ametei{(37.9±5.3)vs(40. 5 ±5. 7 )mm,P <0. 05 land LVEDD[ ( 46. 2 ±9. 1 )vs(58.9 ±11.6)mm, P <0.05 Jwere both less than the preoperative data. Between bioprosthetic valve group and mechanical valve group,postoperative and preoperative ascending aortic diameter,LVEDD and LVEF were similar. Conclusion Aortic valve replacement can improve heart function, and valve type has

  10. Aortic Valve Disease

    Science.gov (United States)

    ... that is safest for you based on your individual symptoms and circumstances. Recovery Recovery Most aortic valve ... is safe to do so. You should anticipate spending several days, but likely not more than a ...

  11. Bicuspid aortic valve

    Science.gov (United States)

    ... aortic disease. In: Otto CM, Bonow RO, eds. Valvular Heart Disease: A Companion to Braunwald's Heart Disease . 4th ed. ... PA: Elsevier Saunders; 2014:chap 13. Carabello BA. Valvular heart disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil ...

  12. Aortic Valve Regurgitation

    Science.gov (United States)

    ... inside your heart that involves heart valves. Rheumatic fever. Rheumatic fever — a complication of strep throat and once a ... the United States — can damage the aortic valve. Rheumatic fever is still prevalent in developing countries but rare ...

  13. Aortic Valve Stenosis

    Science.gov (United States)

    ... evaluation of aortic stenosis in adults. http://www.uptodate.com/home. Accessed April 29, 2014. Mohty D, ... Valvular heart disease in elderly adults. http://www.uptodate.com/home. Accessed May 2, 2014. Bonow RO, ...

  14. A curve-fitting approach to estimate the arterial plasma input function for the assessment of glucose metabolic rate and response to treatment.

    NARCIS (Netherlands)

    Vriens, D.; Geus-Oei, L.F. de; Oyen, W.J.G.; Visser, E.P.

    2009-01-01

    For the quantification of dynamic (18)F-FDG PET studies, the arterial plasma time-activity concentration curve (APTAC) needs to be available. This can be obtained using serial sampling of arterial blood or an image-derived input function (IDIF). Arterial sampling is invasive and often not feasible i

  15. The Influence of Prosodic Input in the Second Language Classroom: Does It Stimulate Child Acquisition of Word Order and Function Words?

    Science.gov (United States)

    Campfield, Dorota E.; Murphy, Victoria A.

    2017-01-01

    This paper reports on an intervention study with young Polish beginners (mean age: 8 years, 3 months) learning English at school. It seeks to identify whether exposure to rhythmic input improves knowledge of word order and function words. The "prosodic bootstrapping hypothesis", relevant in developmental psycholinguistics, provided the…

  16. [Inflammatory abdominal aortic aneurysm].

    Science.gov (United States)

    Ziaja, K; Sedlak, L; Urbanek, T; Kostyra, J; Ludyga, T

    2000-01-01

    The reported incidence of inflammatory abdominal aortic aneurysm (IAAA) is from 2% to 14% of patients with abdominal aortic aneurysm and the etiology of this disease is still discussed--according to the literature several pathogenic theories have been proposed. From 1992 to 1997 32 patients with IAAA were operated on. The patients were mostly symptomatic--abdominal pain was present in 68.75% cases, back pain in 31.25%, fever in 12.5% and weight loss in 6.25% of the operated patients. In all the patients ultrasound examination was performed, in 4 patients CT and in 3 cases urography. All the patients were operated on and characteristic signs of inflammatory abdominal aortic aneurysm like: thickened aortic wall, perianeurysmal infiltration or retroperitoneal fibrosis with involvement of retroperitoneal structures were found. In all cases surgery was performed using transperitoneal approach; in three cases intraoperatively contiguous abdominal organs were injured, which was connected with their involvement into periaortic inflammation. In 4 cases clamping of the aorta was done at the level of the diaphragmatic hiatus. 3 patients (9.37%) died (one patient with ruptured abdominal aortic aneurysm). Authors present diagnostic procedures and the differences in the surgical tactic, emphasizing the necessity of the surgical therapy in patients with inflammatory abdominal aortic aneurysm.

  17. Composition of riparian litter input regulates organic matter decomposition: Implications for headwater stream functioning in a managed forest landscape.

    Science.gov (United States)

    Lidman, Johan; Jonsson, Micael; Burrows, Ryan M; Bundschuh, Mirco; Sponseller, Ryan A

    2017-02-01

    Although the importance of stream condition for leaf litter decomposition has been extensively studied, little is known about how processing rates change in response to altered riparian vegetation community composition. We investigated patterns of plant litter input and decomposition across 20 boreal headwater streams that varied in proportions of riparian deciduous and coniferous trees. We measured a suite of in-stream physical and chemical characteristics, as well as the amount and type of litter inputs from riparian vegetation, and related these to decomposition rates of native (alder, birch, and spruce) and introduced (lodgepole pine) litter species incubated in coarse- and fine-mesh bags. Total litter inputs ranged more than fivefold among sites and increased with the proportion of deciduous vegetation in the riparian zone. In line with differences in initial litter quality, mean decomposition rate was highest for alder, followed by birch, spruce, and lodgepole pine (12, 55, and 68% lower rates, respectively). Further, these rates were greater in coarse-mesh bags that allow colonization by macroinvertebrates. Variance in decomposition rate among sites for different species was best explained by different sets of environmental conditions, but litter-input composition (i.e., quality) was overall highly important. On average, native litter decomposed faster in sites with higher-quality litter input and (with the exception of spruce) higher concentrations of dissolved nutrients and open canopies. By contrast, lodgepole pine decomposed more rapidly in sites receiving lower-quality litter inputs. Birch litter decomposition rate in coarse-mesh bags was best predicted by the same environmental variables as in fine-mesh bags, with additional positive influences of macroinvertebrate species richness. Hence, to facilitate energy turnover in boreal headwaters, forest management with focus on conifer production should aim at increasing the presence of native deciduous

  18. Pentosan polysulfate decreases myocardial expression of the extracellular matrix enzyme ADAMTS4 and improves cardiac function in vivo in rats subjected to pressure overload by aortic banding.

    Directory of Open Access Journals (Sweden)

    Maria Vistnes

    Full Text Available BACKGROUND: We hypothesized that cleavage of the extracellular matrix (ECM proteoglycans versican and aggrecan by ADAMTS (a disintegrin and metalloprotease with thrombospondin motifs proteases, which contributes to stress-induced ECM-reorganization in atherogenesis and osteoarthritis, also play a role in heart failure development. OBJECTIVES: The primary objective was to identify alterations in expression of ADAMTS versicanases and aggrecanases during development of heart failure, while evaluation of the effects of in vivo modulation of relevant changes in ADAMTS activity constituted the secondary objective. METHODS: Myocardial levels of versican, aggrecan, and their ADAMTS cleaving proteases were examined in Wistar rats six weeks after aortic banding (AB, and versican and selected ADAMTS versicanases were further analyzed in neonatal cardiomyocytes (NCM and cardiac fibroblasts (NFB after stimulation by inflammatory mediators. Based on the initial findings, ADAMTS4 was selected the most promising therapeutic target. Thus, rats with AB were treated with pentosan polysulfate (PPS, a polysaccharide with known ADAMTS4-inhibitory properties, and effects on versican fragmentation, left ventricular function and geometry were evaluated. RESULTS: We discovered that myocardial mRNA and protein levels of ADAMTS1 and -4, and mRNA levels of versican, aggrecan, and ADAMTS8 increased after AB, and TNF-α and IL-1β synergistically increased mRNA of versican and ADAMTS4 in NCM and NFB and secretion of ADAMTS4 from NCM. Furthermore, PPS-treatment improved systolic function, demonstrated by an improved fractional shortening (vehicle 48±3% versus PPS 60±1%, p<0.01 after AB. Following PPS-treatment, we observed an ∼80% reduction in myocardial ADAMTS4 mRNA (p = 0.03, and ∼50% reduction in the extracellular amount of the p150 versican fragments (p = 0.05, suggesting reduced versicanase activity. CONCLUSIONS: Our findings suggest that AB induces an

  19. Screening for Abdominal Aortic Aneurysm

    Science.gov (United States)

    Understanding Task Force Recommendations Screening for Abdominal Aortic Aneurysm The U.S. Preventive Services Task Force (Task Force) has issued a final recommendation statement on Screening for Abdominal Aortic Aneurysm. This final ...

  20. Abdominal aortic aneurysm repair - open

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007392.htm Abdominal aortic aneurysm repair - open To use the sharing features on this page, please enable JavaScript. Open abdominal aortic aneurysm repair is surgery to fix a widened part ...

  1. [Congenital aortic stenosis].

    Science.gov (United States)

    Yamaguchi, M

    2001-08-01

    Recent advances in and controversies concerning the management of children with congenital valvular aortic stenosis are discussed. In neonates with critical aortic stenosis, improved survival has recently been reported after surgical open valvotomy and balloon valvuloplasty, although it is difficult at this point to compare the results of the two procedures and determine their differential indications. Good results have also been achieved after extended aortic valvuloplasty for recurrent aortic stenosis and/or insufficiency, but the length of follow-up in these patients is still short. The technique first reported in 1991 for bilateral enlargement fo a small annulus permits the insertion of an aortic valve 3-4 sizes larger than the native annulus. It entails no risk of distorting the mitral valve, damaging the conduction system or important branches of the coronary arteries, or resulting in left ventricular dysfunction. The Ross procedure is now widely applied in the West, with reports of early mortality rates of less than 5% and event-free survival rates of 80-90% during follow-up of 4-8 years. Longer follow-up and continued careful evaluation are required to resolve the issue of possible dilatation and subsequent neoaortic valve dysfunction and pulmonary stenosis due to allograft degeneration after pulmonary autograft root replacement in children.

  2. When operable patients become inoperable: conversion of a surgical aortic valve replacement into transcatheter aortic valve implantation

    DEFF Research Database (Denmark)

    Olsen, Lene Kjaer; Arendrup, Henrik; Engstrøm, Thomas;

    2009-01-01

    Transcatheter aortic valve implantation (TAVI) is a relatively new treatment option for inoperable patients with severe aortic stenosis (AS). This case describes how a planned conventional surgical aortic valve replacement (AVR) on a 73-year-old woman was successfully converted to a TAVI procedure....... On extracorporal circulation it was reconized that the aortic annulus, the coronary ostiae and the proximal part of the ascending aorta were severely calcified making valve implantation impossible. Surgical closure without valve substitution was estimated to be associated with a high risk of mortality due......, and the prosthesis was sutured to the ascending aorta. With some manipulation of the prosthesis it was possible to suture the aorta circumferentially around the fully expanded upper part of the prosthesis. Post-procedurally the patient recovered successfully, with improved function capacity, aortic valve area...

  3. Aortic PWV in Chronic Kidney Disease: A CRIC Ancillary Study

    Science.gov (United States)

    Townsend, Raymond R.; Wimmer, Neil J.; Chirinos, Julio A.; Parsa, Afshin; Weir, Matthew; Perumal, Kalyani; Lash, James P.; Chen, Jing; Steigerwalt, Susan P.; Flack, John; Go, Alan S.; Rafey, Mohammed; Rahman, Mahboob; Sheridan, Angela; Gadegbeku, Crystal A.; Robinson, Nancy A.; Joffe, Marshall

    2009-01-01

    Background Aortic PWV is a measure of arterial stiffness and has proved useful in predicting cardiovascular morbidity and mortality in several populations of patients, including the healthy elderly, hypertensives and those with end stage renal disease receiving hemodialysis. Little data exist characterizing aortic stiffness in patients with chronic kidney disease who are not receiving dialysis, and in particular the effect of reduced kidney function on aortic PWV. Methods We performed measurements of aortic PWV in a cross-sectional cohort of participants enrolled in the Chronic Renal Insufficiency Cohort (CRIC) study to determine factors which predict increased aortic PWV in chronic kidney disease. Results PWV measurements were obtained in 2564 participants. The tertiles of aortic PWV (adjusted for waist circumference) were 10.2 m/sec with an overall mean (± S.D.) value of 9.48 ± 3.03 m/sec [95% CI = 9.35–9.61 m/sec]. Multivariable regression identified significant independent positive associations of age, blood glucose concentrations, race, waist circumference, mean arterial blood pressure, gender, and presence of diabetes with aortic PWV and a significant negative association with the level of kidney function. Conclusions The large size of this unique cohort, and the targeted enrollment of chronic kidney disease participants provides an ideal situation to study the role of reduced kidney function as a determinant of arterial stiffness. Arterial stiffness may be a significant component of the enhanced cardiovascular risk associated with kidney failure. PMID:20019670

  4. Aortic valve replacement

    DEFF Research Database (Denmark)

    Kapetanakis, Emmanouil I; Athanasiou, Thanos; Mestres, Carlos A;

    2008-01-01

    mortality were collected. Group analysis by patient geographic distribution and by annular diameter of the prosthesis utilized was conducted. Patients with a manufacturer's labeled prosthesis size > or = 21 mm were assigned to the 'large' aortic size subset, while those with a prosthesis size ... assigned to the 'small' aortic size subset. Effective orifice area indices were calculated for all patients to assess the geographic distribution of patient-prosthesis mismatch. Univariable and multivariable logistic regression analyses adjusting for possible confounding variables were performed. RESULTS...... differences in the distribution of either gender or BSA. In the multivariable model, south European patients were seven times more likely to receive a smaller-sized aortic valve (OR = 6.5, 95% CI = 4.82-8.83, p

  5. Robotic aortic surgery.

    Science.gov (United States)

    Duran, Cassidy; Kashef, Elika; El-Sayed, Hosam F; Bismuth, Jean

    2011-01-01

    Surgical robotics was first utilized to facilitate neurosurgical biopsies in 1985, and it has since found application in orthopedics, urology, gynecology, and cardiothoracic, general, and vascular surgery. Surgical assistance systems provide intelligent, versatile tools that augment the physician's ability to treat patients by eliminating hand tremor and enabling dexterous operation inside the patient's body. Surgical robotics systems have enabled surgeons to treat otherwise untreatable conditions while also reducing morbidity and error rates, shortening operative times, reducing radiation exposure, and improving overall workflow. These capabilities have begun to be realized in two important realms of aortic vascular surgery, namely, flexible robotics for exclusion of complex aortic aneurysms using branched endografts, and robot-assisted laparoscopic aortic surgery for occlusive and aneurysmal disease.

  6. Image-Derived Input Function Derived from a Supervised Clustering Algorithm: Methodology and Validation in a Clinical Protocol Using [11C](R)-Rolipram

    OpenAIRE

    Chul Hyoung Lyoo; Paolo Zanotti-Fregonara; Zoghbi, Sami S.; Jeih-San Liow; Rong Xu; Pike, Victor W.; Zarate, Carlos A.; Masahiro Fujita; Innis, Robert B.

    2014-01-01

    Image-derived input function (IDIF) obtained by manually drawing carotid arteries (manual-IDIF) can be reliably used in [(11)C](R)-rolipram positron emission tomography (PET) scans. However, manual-IDIF is time consuming and subject to inter- and intra-operator variability. To overcome this limitation, we developed a fully automated technique for deriving IDIF with a supervised clustering algorithm (SVCA). To validate this technique, 25 healthy controls and 26 patients with moderate to severe...

  7. Stanford B型主动脉夹层对凝血功能的影响%Influence of type B aortic dissection on coagulation function

    Institute of Scientific and Technical Information of China (English)

    何亮; 郭盛; 杜宇奎

    2011-01-01

    目的 探讨主动脉Stanford B型主动脉夹层患者凝血功能的变化及其临床意义.方法 2002年1月至2011年1月新疆维吾尔自治区人民医院收治stanford B型主动脉夹层99例,选性别与年龄匹配的正常对照组95例,全自动血凝分析仪检测入选人群入院时国际化标准比值(INR)、部分凝血活酶时间(APrr)、纤维蛋白原(FIB)、凝血酶时间(TT)和D-二聚体(DD).结果 夹层组INR、APTY、FIB、DD均高于对照组,TT低于对照组(P均<0.01).主动脉夹层分期内比较,亚急性及慢性期组夹层INR、FIB高于急性期夹层组(P均<0.01),APTr、DD、TT未见明显改变.结论 Stanford B型主动脉夹层表现为凝血与纤溶持续激活,凝血与纤溶间的平衡被破坏而产生高凝状态.%Objective To explore the changes of blood coagulation function and clinical significances in type B Aortic Dissection(AD).Methods 99 patients with type B AD group,95 persons in healthy control group weIe selected respectively(NC).The detection and analysis of international nomtalized ratio(INR),activated partial thromboplastin time(APTT),thrombin time(TT),fibfinogen(Fib)and D dimer(D-D)were conducted.Results INR,APTT,FIB,DD in AD group signifcantly increased compared with NC group,TT decreased respectively(P<0.01).Subacute and chronic AD showed a significant increase in INR and FIB.Corupamd with acute group.P<0.01.Conclusions AD is characterized by activation of both coagulation and fibrinolysis,resulting in an imbalance between coagulation and fibrinolysis that leading to a hypercoagulation state.

  8. Subcoronary versus supracoronary aortic stenosis. an experimental evaluation

    Directory of Open Access Journals (Sweden)

    Hasenkam J Michael

    2011-08-01

    Full Text Available Abstract Background Valvular aortic stenosis is the most common cause of left ventricular hypertrophy due to gradually increasing pressure work. As the stenosis develop the left ventricular hypertrophy may lead to congestive heart failure, increased risk of perioperative complications and also increased risk of sudden death. A functional porcine model imitating the pathophysiological nature of valvular aortic stenosis is very much sought after in order to study the geometrical and pathophysiological changes of the left ventricle, timing of surgery and also pharmacological therapy in this patient group. Earlier we developed a porcine model for aortic stenosis based on supracoronary aortic banding, this model may not completely imitate the pathophysiological changes that occurs when valvular aortic stenosis is present including the coronary blood flow. It would therefore be desirable to optimize this model according to the localization of the stenosis. Methods In 20 kg pigs subcoronary (n = 8, supracoronary aortic banding (n = 8 or sham operation (n = 4 was preformed via a left lateral thoracotomy. The primary endpoint was left ventricular wall thickness; secondary endpoints were heart/body weight ratio and the systolic/diastolic blood flow ratio in the left anterior descending coronary. Statistical evaluation by oneway anova and unpaired t-test. Results Sub- and supracoronary banding induce an equal degree of left ventricular hypertrophy compared with the control group. The coronary blood flow ratio was slightly but not significantly higher in the supracoronary group (ratio = 0.45 compared with the two other groups (subcoronary ratio = 0.36, control ratio = 0.34. Conclusions A human pathophysiologically compatible porcine model for valvular aortic stenosis was developed by performing subcoronary aortic banding. Sub- and supracoronary aortic banding induce an equal degree of left ventricular hypertrophy. This model may be valid for experimental

  9. Unoperated aortic aneurysm

    DEFF Research Database (Denmark)

    Perko, M J; Nørgaard, M; Herzog, T M;

    1995-01-01

    From 1984 to 1993, 1,053 patients were admitted with aortic aneurysm (AA) and 170 (15%) were not operated on. The most frequent reason for nonoperative management was presumed technical inoperability. Survivals for patients with thoracic, thoracoabdominal, and abdominal AA were comparable...... hypertension were predictive of mortality, whereas...

  10. First-in-man transcatheter aortic valve implantation of a 20-mm Edwards SAPIEN XT valve: one step forward for the treatment of patients with severe aortic stenosis and small aortic annulus.

    Science.gov (United States)

    Rodés-Cabau, Josep; DeLarochellière, Robert; Dumont, Eric

    2012-04-01

    We present the case of an 85-year-old woman diagnosed with severe aortic stenosis, porcelain aorta, and a small aortic annulus (17.3 mm), who underwent successful transfemoral transcatheter aortic valve implantation (TAVI) with a 20-mm Edwards SAPIEN XT valve using the NovaFlex+ delivery system. At 1-month follow-up the patient was in NYHA functional class I, and Doppler echocardiography showed a mean residual gradient of 15 mm Hg and trivial paravalvular aortic regurgitation. This case, which shows for the first time the feasibility of TAVI with a 20-mm valve, opens a new avenue for the challenging treatment of patients with aortic stenosis and a small aortic annulus.

  11. Post-stenotic aortic dilatation

    Directory of Open Access Journals (Sweden)

    Jahangiri Marjan

    2006-03-01

    Full Text Available Abstract Aortic stenosis is the most common valvular heart disease affecting up to 4% of the elderly population. It can be associated with dilatation of the ascending aorta and subsequent dissection. Post-stenotic dilatation is seen in patients with AS and/or aortic regurgitation, patients with a haemodynamically normal bicuspid aortic valve and following aortic valve replacement. Controversy exists as to whether to replace the aortic root and ascending aorta at the time of aortic valve replacement, an operation that potentially carries a higher morbidity and mortality. The aetiology of post-stenotic aortic dilatation remains controversial. It may be due to haemodynamic factors caused by a stenotic valve, involving high velocity and turbulent flow downstream of the stenosis, or due to intrinsic pathology of the aortic wall. This may involve an abnormality in the process of extracellular matrix remodelling in the aortic wall including inadequate synthesis, degradation and transport of extracellular matrix proteins. This article reviews the aetiology, pathology and management of patients with post-stenotic aortic dilatation.

  12. Catalase overexpression in aortic smooth muscle prevents pathological mechanical changes underlying abdominal aortic aneurysm formation.

    Science.gov (United States)

    Maiellaro-Rafferty, Kathryn; Weiss, Daiana; Joseph, Giji; Wan, William; Gleason, Rudolph L; Taylor, W Robert

    2011-08-01

    The causality of the associations between cellular and mechanical mechanisms of abdominal aortic aneurysm (AAA) formation has not been completely defined. Because reactive oxygen species are established mediators of AAA growth and remodeling, our objective was to investigate oxidative stress-induced alterations in aortic biomechanics and microstructure during subclinical AAA development. We investigated the mechanisms of AAA in an angiotensin II (ANG II) infusion model of AAA in apolipoprotein E-deficient (apoE(-/-)) mice that overexpress catalase in vascular smooth muscle cells (apoE(-/-)xTg(SMC-Cat)). At baseline, aortas from apoE(-/-)xTg(SMC-Cat) exhibited increased stiffness and the microstructure was characterized by 50% more collagen content and less elastin fragmentation. ANG II treatment for 7 days in apoE(-/-) mice altered the transmural distribution of suprarenal aortic circumferential strain (quantified by opening angle, which increased from 130 ± 1° at baseline to 198 ± 8° after 7 days of ANG II treatment) without obvious changes in the aortic microstructure. No differences in aortic mechanical behavior or suprarenal opening angle were observed in apoE(-/-)xTg(SMC-Cat) after 7 days of ANG II treatment. These data suggest that at the earliest stages of AAA development H(2)O(2) is functionally important and is involved in the control of local variations in remodeling across the vessel wall. They further suggest that reduced elastin integrity at baseline may predispose the abdominal aorta to aneurysmal mechanical remodeling.

  13. Management of Recurrent Delayed Neurologic Deficit After Thoracoabdominal Aortic Operation.

    Science.gov (United States)

    Boutrous, Mina L; Afifi, Rana O; Safi, Hazim J; Estrera, Anthony L

    2016-01-01

    Delayed neurologic deficit (DND) is a devastating adverse event after thoracoabdominal aortic aneurysm repair. Multiple adjuncts have been devised to counteract the development of DND, most notably cerebrospinal fluid (CSF) drainage. We report a case of a 63-year-old woman in whom DND developed four times during the first 10 days after her thoracoabdominal aortic operation. This necessitated lumbar drain "weaning" to allow for a slowly rising CSF pressure and preservation of lower extremity motor function.

  14. Transcatheter aortic valve-in-valve implantation of a CoreValve in a degenerated aortic bioprosthesis.

    Science.gov (United States)

    Bruschi, Giuseppe; DeMarco, Federico; Oreglia, Jacopo; Colombo, Paola; Fratto, Pasquale; Lullo, Francesca; Paino, Roberto; Martinelli, Luigi; Klugmann, Silvio

    2010-03-01

    In recent years percutaneous aortic valve implantation has emerged as an alternative therapy to treat patients with symptomatic aortic stenosis considered to be high-risk surgical candidates. We report our experience of a percutaneous retrograde CoreValve implantation in a 77-year-old female with aortic bioprosthesis structural degeneration. The patient underwent aortic valve replacement for aortic stenosis in 1999 with the implantation of a 23 mm Carpentier-Edwards; her last echocardiography showed a severe bioprosthesis stenosis. After evaluation by cardiac surgeons and cardiologist, considering the high risk re-do surgical procedure (Logistic Euroscore 30%) and severe comorbidities (severe pulmonary hypertension, hepatocellular carcinoma and severe osteoporosis), a percutaneous aortic valve-in-valve replacement was preferred. A successful percutaneous 26 mm CoreValve prosthesis implantation was performed with the patient awake with local anesthesia and mild sedation. The patient was discharged after 10 days of hospitalization and she is in NYHA functional class I at follow-up. Our experience, characterized by a multidisciplinary approach, necessary to offer the safest conditions and care for patients, demonstrates the feasibility of a new, promising indication for the use of a transcatheter valve implantation: percutaneous treatment of a degenerated aortic bioprosthesis.

  15. Imaging analysis of collagen fiber networks in cusps of porcine aortic valves: effect of their local distribution and alignment on valve functionality.

    Science.gov (United States)

    Mega, Mor; Marom, Gil; Halevi, Rotem; Hamdan, Ashraf; Bluestein, Danny; Haj-Ali, Rami

    2016-01-01

    The cusps of native aortic valve (AV) are composed of collagen bundles embedded in soft tissue, creating a heterogenic tissue with asymmetric alignment in each cusp. This study compares native collagen fiber networks (CFNs) with a goal to better understand their influence on stress distribution and valve kinematics. Images of CFNs from five porcine tricuspid AVs are analyzed and fluid-structure interaction models are generated based on them. Although the valves had similar overall kinematics, the CFNs had distinctive influence on local mechanics. The regions with dilute CFN are more prone to damage since they are subjected to higher stress magnitudes.

  16. Image-derived and arterial blood sampled input functions for quantitative PET imaging of the angiotensin II subtype 1 receptor in the kidney

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Tao; Tsui, Benjamin M. W.; Li, Xin; Vranesic, Melin; Lodge, Martin A.; Gulaldi, Nedim C. M.; Szabo, Zsolt, E-mail: zszabo@jhmi.edu [Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins School of Medicine, Baltimore, Maryland 21287 (United States)

    2015-11-15

    Purpose: The radioligand {sup 11}C-KR31173 has been introduced for positron emission tomography (PET) imaging of the angiotensin II subtype 1 receptor in the kidney in vivo. To study the biokinetics of {sup 11}C-KR31173 with a compartmental model, the input function is needed. Collection and analysis of arterial blood samples are the established approach to obtain the input function but they are not feasible in patients with renal diseases. The goal of this study was to develop a quantitative technique that can provide an accurate image-derived input function (ID-IF) to replace the conventional invasive arterial sampling and test the method in pigs with the goal of translation into human studies. Methods: The experimental animals were injected with [{sup 11}C]KR31173 and scanned up to 90 min with dynamic PET. Arterial blood samples were collected for the artery derived input function (AD-IF) and used as a gold standard for ID-IF. Before PET, magnetic resonance angiography of the kidneys was obtained to provide the anatomical information required for derivation of the recovery coefficients in the abdominal aorta, a requirement for partial volume correction of the ID-IF. Different image reconstruction methods, filtered back projection (FBP) and ordered subset expectation maximization (OS-EM), were investigated for the best trade-off between bias and variance of the ID-IF. The effects of kidney uptakes on the quantitative accuracy of ID-IF were also studied. Biological variables such as red blood cell binding and radioligand metabolism were also taken into consideration. A single blood sample was used for calibration in the later phase of the input function. Results: In the first 2 min after injection, the OS-EM based ID-IF was found to be biased, and the bias was found to be induced by the kidney uptake. No such bias was found with the FBP based image reconstruction method. However, the OS-EM based image reconstruction was found to reduce variance in the subsequent

  17. Tobacco smoking and aortic aneurysm

    DEFF Research Database (Denmark)

    Sode, Birgitte F; Nordestgaard, Børge G; Grønbæk, Morten

    2012-01-01

    General Population Study, respectively. According to the magnitude of the hazard ratios, tobacco consumption was the most important risk factor for hospitalization and death from aortic aneurysm, followed by male sex and hypertension in both cohorts. The population attributable risk of aortic aneurysm...... outcomes due to tobacco consumption was 64% and 47% in the Copenhagen City Heart Study and Copenhagen General Population Study, respectively, and ranked highest among population attributable risks of aortic aneurysm in both cohorts. The absolute 10-year risk for hospitalization or death from aortic......BACKGROUND: We determined the predictive power of tobacco smoking on aortic aneurysm as opposed to other risk factors in the general population. METHODS: We recorded tobacco smoking and other risk factors at baseline, and assessed hospitalization and death from aortic aneurysm in 15,072 individuals...

  18. Ruptured abdominal aortic aneurysm.

    Science.gov (United States)

    Sachs, T; Schermerhorn, M

    2010-06-01

    Ruptured abdominal aortic aneurysm (AAA) continues to be one of the most lethal vascular pathologies we encounter. Its management demands prompt and efficient evaluation and repair. Open repair has traditionally been the mainstay of treatment. However, the introduction of endovascular techniques has altered the treatment algorithm for ruptured AAA in most major medical centers. We present recent literature and techniques for ruptured AAA and its surgical management.

  19. Infrarenal Aortic Occlusion

    Science.gov (United States)

    Traverso, L. W.; Baker, J. D.; Dainko, E. A.; Machleder, H. I.

    1978-01-01

    Twenty-eight patients with total occlusion of the infrarenal aorta have been seen at the UCLA Hospitals in the past 11 years. Claudication was the presenting complaint in all but one patient, with one-third having ischemic rest pain. The average age of these patients was 54 years, and their histories revealed a surprising absence of myocardial infarction, stroke, or diabetes, although 40% had essential hypertension. Heavy tobacco use, however, was characteristic of the entire group. Arteriography proved valuable in identifying and characterizing the vascular abnormalities, but posed problems in technique and interpretation. Significant distal arterial disease was detected radiographically in only 21% of these patients. Operative correction of the aortic occlusion was performed on 26 patients, 18 by aortic bypass grafts and eight by aorto-iliac endarterectomy, with one early postoperative death. Although the thrombus extended to the renal artery origins in 77% of the cases, a well-designed technical approach did not require renal artery occlusion. Using serial creatinine determinations, one case of renal insufficiency was detected which was associated with prolonged postoperative hypotension. Although the extent of distal disease was more severe in those who underwent bypass, symptoms of claudication returned earlier and were more prominent in the endarterectomy group. This recurrence of systems was not favorably altered by sympathectomy performed concomitantly with the initial procedure. Even though this condition seems to pose difficult technical obstacles and has a poor prognosis, infrarenal aortic occlusion can be successfully treated by aortic bypass, with favorable long-term results, if particular attention is paid to elements of the preoperative evaluation and the intraoperative technical requirements peculiar to this relatively uncommon disease entity. ImagesFig. 1.Fig. 2.Fig. 3. PMID:646479

  20. The Functional Upregulation of Piriform Cortex Is Associated with Cross-Modal Plasticity in Loss of Whisker Tactile Inputs

    OpenAIRE

    Bing Ye; Li Huang; Zilong. Gao; Ping Chen; Hong Ni; Sudong Guan; Yan Zhu; Jin-Hui Wang

    2012-01-01

    BACKGROUND: Cross-modal plasticity is characterized as the hypersensitivity of remaining modalities after a sensory function is lost in rodents, which ensures their awareness to environmental changes. Cellular and molecular mechanisms underlying cross-modal sensory plasticity remain unclear. We aim to study the role of different types of neurons in cross-modal plasticity. METHODOLOGY/PRINCIPAL FINDINGS: In addition to behavioral tasks in mice, whole-cell recordings at the excitatory and inhib...

  1. The multiple-function multi-input/multi-output digital controller system for the AFW wind-tunnel model

    Science.gov (United States)

    Hoadley, Sherwood T.; Mcgraw, Sandra M.

    1992-01-01

    A real time multiple-function digital controller system was developed for the Active Flexible Wing (AFW) Program. The digital controller system (DCS) allowed simultaneous execution of two control laws: flutter suppression and either roll trim or a rolling maneuver load control. The DCS operated within, but independently of, a slower host operating system environment, at regulated speeds up to 200 Hz. It also coordinated the acquisition, storage, and transfer of data for near real time controller performance evaluation and both open- and closed-loop plant estimation. It synchronized the operation of four different processing units, allowing flexibility in the number, form, functionality, and order of control laws, and variability in the selection of the sensors and actuators employed. Most importantly, the DCS allowed for the successful demonstration of active flutter suppression to conditions approximately 26 percent (in dynamic pressure) above the open-loop boundary in cases when the model was fixed in roll and up to 23 percent when it was free to roll. Aggressive roll maneuvers with load control were achieved above the flutter boundary. The purpose here is to present the development, validation, and wind tunnel testing of this multiple-function digital controller system.

  2. CT of thoracic aortic aneurysms.

    Science.gov (United States)

    Posniak, H V; Olson, M C; Demos, T C; Benjoya, R A; Marsan, R E

    1990-09-01

    Aneurysms of the thoracic aorta are most often the result of arteriosclerotic disease. Other causes include degeneration of the medial layer of the aortic wall, either idiopathically or due to genetic disorders such as Marfan syndrome; aortic dissection; trauma; syphilis and other bacterial infection; noninfective aortitis; and congenital anomaly. We review normal anatomy of the aorta and discuss our technique and interpretation of computed tomography (CT) in the evaluation of the thoracic aorta. We illustrate the CT appearance of different types of aortic aneurysms as well as discuss the use of CT for assessing complications of aneurysms, for postoperative follow-up, and in the differentiation of aortic aneurysm from a paraaortic mass.

  3. Micromanaging Abdominal Aortic Aneurysms

    Directory of Open Access Journals (Sweden)

    Lars Maegdefessel

    2013-07-01

    Full Text Available The contribution of abdominal aortic aneurysm (AAA disease to human morbidity and mortality has increased in the aging, industrialized world. In response, extraordinary efforts have been launched to determine the molecular and pathophysiological characteristics of the diseased aorta. This work aims to develop novel diagnostic and therapeutic strategies to limit AAA expansion and, ultimately, rupture. Contributions from multiple research groups have uncovered a complex transcriptional and post-transcriptional regulatory milieu, which is believed to be essential for maintaining aortic vascular homeostasis. Recently, novel small noncoding RNAs, called microRNAs, have been identified as important transcriptional and post-transcriptional inhibitors of gene expression. MicroRNAs are thought to “fine tune” the translational output of their target messenger RNAs (mRNAs by promoting mRNA degradation or inhibiting translation. With the discovery that microRNAs act as powerful regulators in the context of a wide variety of diseases, it is only logical that microRNAs be thoroughly explored as potential therapeutic entities. This current review summarizes interesting findings regarding the intriguing roles and benefits of microRNA expression modulation during AAA initiation and propagation. These studies utilize disease-relevant murine models, as well as human tissue from patients undergoing surgical aortic aneurysm repair. Furthermore, we critically examine future therapeutic strategies with regard to their clinical and translational feasibility.

  4. The multiple-function multi-input/multi-output digital controller system for the AFW wind tunnel model

    Science.gov (United States)

    Hoadley, Sherwood T.; Mcgraw, Sandra M.

    1992-01-01

    A real-time multiple-function digital controller system was developed for the Active Flexible Wing (AFW) Program. The digital controller system (DCS) allowed simultaneous execution of two control laws: flutter suppression and either roll trim or a rolling maneuver load control. The DCS operated within, but independently of, a slower host operating system environment, at regulated speeds up to 200 Hz. It also coordinated the acquisition, storage, and transfer of data for near real-time controller performance evaluation and both open- and closed-loop plant estimation. It synchronized the operation of four different processing units, allowing flexibility in the number, form, functionality, and order of control laws, and variability in selection of sensors and actuators employed. Most importantly, the DCS allowed for the successful demonstration of active flutter suppression to conditions approximately 26 percent (in dynamic pressure) above the open-loop boundary in cases when the model was fixed in roll and up to 23 percent when it was free to roll. Aggressive roll maneuvers with load control were achieved above the flutter boundary.

  5. Linear functional observers with guaranteed ɛ-convergence for discrete time-delay systems with input/output disturbances

    Science.gov (United States)

    Nguyen, M. C.; Trinh, H.; Nam, P. T.

    2016-10-01

    The problem of designing linear functional observers for discrete time-delay systems with unknown-but-bounded disturbances in both the plant and the output is considered for the first time in this paper. A novel approach to design a minimum-order observer is proposed to guarantee that the observer error is ε-convergent, which means that the estimate converges robustly within an ε-bound of the true state. Conditions for the existence of this observer are first derived. Then, by utilising an extended Lyapunov-Krasovskii functional and the free-weighting matrix technique, a sufficient condition for ε-convergence of the observer error system is given. This condition is presented in terms of linear matrix inequalities with two parameters needed to be tuned, so that it can be efficiently solved by incorporating a two-dimensional search method into convex optimisation algorithms to obtain the smallest possible value for ε. Three numerical examples, including the well-known single-link flexible joint robotic system, are given to illustrate the feasibility and effectiveness of our results.

  6. Using Python for scientific computing: Efficient and flexible evaluation of the statistical characteristics of functions with multivariate random inputs

    Science.gov (United States)

    Chudoba, R.; Sadílek, V.; Rypl, R.; Vořechovský, M.

    2013-02-01

    This paper examines the feasibility of high-level Python based utilities for numerically intensive applications via an example of a multidimensional integration for the evaluation of the statistical characteristics of a random variable. We discuss the approaches to the implementation of mathematically formulated incremental expressions using high-level scripting code and low-level compiled code. Due to the dynamic typing of the Python language, components of the algorithm can be easily coded in a generic way as algorithmic templates. Using the Enthought Development Suite they can be effectively assembled into a flexible computational framework that can be configured to execute the code for arbitrary combinations of integration schemes and versions of instantiated code. The paper describes the development cycle using a simple running example involving averaging of a random two-parametric function that includes discontinuity. This example is also used to compare the performance of the available algorithmic and executional features. The implemented package including further examples and the results of performance studies have been made available via the free repository [1] and CPCP library. Program summaryProgram title: spirrid Catalogue identifier: AENL_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AENL_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Special licence provided by the author No. of lines in distributed program, including test data, etc.: 10722 No. of bytes in distributed program, including test data, etc.: 157099 Distribution format: tar.gz Programming language: Python and C. Computer: PC. Operating system: LINUX, UNIX, Windows. Classification: 4.13, 6.2. External routines: NumPy (http://numpy.scipy.org/), SciPy (http://www.scipy.com) Nature of problem: Evaluation of the statistical moments of a function of random variables. Solution method: Direct multidimensional

  7. Transcatheter Aortic Valve Replacement in Bicuspid Aortic Valve Disease

    DEFF Research Database (Denmark)

    Mylotte, Darren; Lefevre, Thierry; Søndergaard, Lars

    2014-01-01

    BACKGROUND: Limited information exists describing the results of transcatheter aortic valve (TAV) replacement in patients with bicuspid aortic valve (BAV) disease (TAV-in-BAV). OBJECTIVES: This study sought to evaluate clinical outcomes of a large cohort of patients undergoing TAV-in-BAV. METHODS...

  8. Mast Cells in Abdominal Aortic Aneurysms

    DEFF Research Database (Denmark)

    Shi, Guo-Ping; Lindholt, Jes Sanddal

    2013-01-01

    Mast cells (MCs) are proinflammatory cells that play important roles in allergic responses, tumor growth, obesity, diabetes, atherosclerosis, and abdominal aortic aneurysm (AAA). Although the presence and function of MCs in atherosclerotic lesions have been thoroughly studied in human specimens...... neighboring cells, degrade extracellular matrix proteins, process latent bioactive molecules, promote angiogenesis, recruit additional inflammatory cells, and stimulate vascular cell apoptosis. These activities associate closely with medial elastica breakdown, medial smooth-muscle cell loss and thinning...

  9. MAT2A mutations predispose individuals to thoracic aortic aneurysms.

    Science.gov (United States)

    Guo, Dong-chuan; Gong, Limin; Regalado, Ellen S; Santos-Cortez, Regie L; Zhao, Ren; Cai, Bo; Veeraraghavan, Sudha; Prakash, Siddharth K; Johnson, Ralph J; Muilenburg, Ann; Willing, Marcia; Jondeau, Guillaume; Boileau, Catherine; Pannu, Hariyadarshi; Moran, Rocio; Debacker, Julie; Bamshad, Michael J; Shendure, Jay; Nickerson, Deborah A; Leal, Suzanne M; Raman, C S; Swindell, Eric C; Milewicz, Dianna M

    2015-01-08

    Up to 20% of individuals who have thoracic aortic aneurysms or acute aortic dissections but who do not have syndromic features have a family history of thoracic aortic disease. Significant genetic heterogeneity is established for this familial condition. Whole-genome linkage analysis and exome sequencing of distant relatives from a large family with autosomal-dominant inheritance of thoracic aortic aneurysms variably associated with the bicuspid aortic valve was used for identification of additional genes predisposing individuals to this condition. A rare variant, c.1031A>C (p.Glu344Ala), was identified in MAT2A, which encodes methionine adenosyltransferase II alpha (MAT IIα). This variant segregated with disease in the family, and Sanger sequencing of DNA from affected probands from unrelated families with thoracic aortic disease identified another MAT2A rare variant, c.1067G>A (p.Arg356His). Evidence that these variants predispose individuals to thoracic aortic aneurysms and dissections includes the following: there is a paucity of rare variants in MAT2A in the population; amino acids Glu344 and Arg356 are conserved from humans to zebrafish; and substitutions of these amino acids in MAT Iα are found in individuals with hypermethioninemia. Structural analysis suggested that p.Glu344Ala and p.Arg356His disrupt MAT IIα enzyme function. Knockdown of mat2aa in zebrafish via morpholino oligomers disrupted cardiovascular development. Co-transfected wild-type human MAT2A mRNA rescued defects of zebrafish cardiovascular development at significantly higher levels than mRNA edited to express either the Glu344 or Arg356 mutants, providing further evidence that the p.Glu344Ala and p.Arg356His substitutions impair MAT IIα function. The data presented here support the conclusion that rare genetic variants in MAT2A predispose individuals to thoracic aortic disease.

  10. Aortic root geometry in aortic stenosis patients (a SEAS substudy)

    DEFF Research Database (Denmark)

    Bahlmann, Edda; Nienaber, Christoph A; Cramariuc, Dana

    2011-01-01

    AIMS: To report aortic root geometry by echocardiography in a large population of healthy, asymptomatic aortic stenosis (AS) patients in relation to current vendor-specified requirements for transcatheter aortic valve implantation (TAVI). METHODS AND RESULTS: Baseline data in 1481 patients...... with asymptomatic AS (mean age 67 years, 39% women) in the Simvastatin Ezetimibe in AS study were used. The inner aortic diameter was measured at four levels: annulus, sinus of Valsalva, sinotubular junction and supracoronary, and sinus height as the annulo-junctional distance. Analyses were based on vendor......-specified requirements for the aortic root geometry for current available prostheses, CoreValve and Edwards-Sapien. The ratio of sinus of Valsalva height to sinus width was 1:2. In multivariate linear regression analysis, larger sinus of Valsalva height was associated with older age, larger sinus of Valsalva diameter...

  11. Chaos and asymptotical stability in discrete-time recurrent neural networks with generalized input-output function

    Institute of Scientific and Technical Information of China (English)

    WANG; Jinliang

    2001-01-01

    Surveys, 1993, 7: 305.[16]Shephand, N., Statistical aspects of ARCH and stochastic volatility, in Time Series Models in Econometrics, Finance and Other Fields (eds. Cox, D. R., Hinkley, D. V., Barndorff-Nielsen, O. E.), London: Chapman & Hall, 1996, 1.[17]Pantula, S. G., Estimation of autoregressive models with ARCH errors, Sankhya, Ser. B, 1988, 50: 119.[18]Campbell, J. Y., Lo, A. W., Mackinlay, A. C., The Econometrics of Financial Markets, Princeton: Princeton University Press, 1997, 488.[19]Fan, J., Gijbels, I., Local Polynomial Modeling and Its Applications, London: Chapman & Hall, 1996.[20]Lu, Z. D., A note on geometric ergodicity of autoregressive conditional heteroscedasticity (ARCH) model, Statistics and Probability Letters, 1996, 30: 305.[21]Robinson, P. M., Nonparametric estimators for time series, Journal of Time Series Analysis, 1983, 4: 185.[22]Stone, C. J., Optimal rates of convergence for nonparametric estimators, Annals of Statistics, 1980, 8: 1348.[23]Stone, C. J., Optimal global rates of convergence for nonparametric kernel regression, Annals of Statistics, 1982, 10: 1040.[24]Truong, Y. M., Stone, C. J., Nonparametric function estimation involving time series, Annals of Statistics, 1992, 20: 77.[25]Masry, E., Multivariate polynomial regression for time series; uniform strong consistency and rates, Journal of Time Series Analysis, 1996, 17: 571.[26]Ruppert, D., Wand, M. P., Multivariate locally weighted least squares regression, Annals of Statistics, 1994, 22: 1346.[27]Bollerslev, T., Generalized autoregressive conditional heteroscedasticity, Journal of Econometrics, 1986, 31: 307.[28]Engle, R. F., Granger, C. W. J., Co-integration and error-correction: representation, estimation and testing, Econometrica, 1987, 55: 251.

  12. Image-derived input function derived from a supervised clustering algorithm: methodology and validation in a clinical protocol using [11C](R)-rolipram.

    Science.gov (United States)

    Lyoo, Chul Hyoung; Zanotti-Fregonara, Paolo; Zoghbi, Sami S; Liow, Jeih-San; Xu, Rong; Pike, Victor W; Zarate, Carlos A; Fujita, Masahiro; Innis, Robert B

    2014-01-01

    Image-derived input function (IDIF) obtained by manually drawing carotid arteries (manual-IDIF) can be reliably used in [(11)C](R)-rolipram positron emission tomography (PET) scans. However, manual-IDIF is time consuming and subject to inter- and intra-operator variability. To overcome this limitation, we developed a fully automated technique for deriving IDIF with a supervised clustering algorithm (SVCA). To validate this technique, 25 healthy controls and 26 patients with moderate to severe major depressive disorder (MDD) underwent T1-weighted brain magnetic resonance imaging (MRI) and a 90-minute [(11)C](R)-rolipram PET scan. For each subject, metabolite-corrected input function was measured from the radial artery. SVCA templates were obtained from 10 additional healthy subjects who underwent the same MRI and PET procedures. Cluster-IDIF was obtained as follows: 1) template mask images were created for carotid and surrounding tissue; 2) parametric image of weights for blood were created using SVCA; 3) mask images to the individual PET image were inversely normalized; 4) carotid and surrounding tissue time activity curves (TACs) were obtained from weighted and unweighted averages of each voxel activity in each mask, respectively; 5) partial volume effects and radiometabolites were corrected using individual arterial data at four points. Logan-distribution volume (V T/f P) values obtained by cluster-IDIF were similar to reference results obtained using arterial data, as well as those obtained using manual-IDIF; 39 of 51 subjects had a V T/f P error of 10%. With automatic voxel selection, cluster-IDIF curves were less noisy than manual-IDIF and free of operator-related variability. Cluster-IDIF showed widespread decrease of about 20% [(11)C](R)-rolipram binding in the MDD group. Taken together, the results suggest that cluster-IDIF is a good alternative to full arterial input function for estimating Logan-V T/f P in [(11)C](R)-rolipram PET clinical scans. This

  13. Image-derived input function derived from a supervised clustering algorithm: methodology and validation in a clinical protocol using [11C](R-rolipram.

    Directory of Open Access Journals (Sweden)

    Chul Hyoung Lyoo

    Full Text Available Image-derived input function (IDIF obtained by manually drawing carotid arteries (manual-IDIF can be reliably used in [(11C](R-rolipram positron emission tomography (PET scans. However, manual-IDIF is time consuming and subject to inter- and intra-operator variability. To overcome this limitation, we developed a fully automated technique for deriving IDIF with a supervised clustering algorithm (SVCA. To validate this technique, 25 healthy controls and 26 patients with moderate to severe major depressive disorder (MDD underwent T1-weighted brain magnetic resonance imaging (MRI and a 90-minute [(11C](R-rolipram PET scan. For each subject, metabolite-corrected input function was measured from the radial artery. SVCA templates were obtained from 10 additional healthy subjects who underwent the same MRI and PET procedures. Cluster-IDIF was obtained as follows: 1 template mask images were created for carotid and surrounding tissue; 2 parametric image of weights for blood were created using SVCA; 3 mask images to the individual PET image were inversely normalized; 4 carotid and surrounding tissue time activity curves (TACs were obtained from weighted and unweighted averages of each voxel activity in each mask, respectively; 5 partial volume effects and radiometabolites were corrected using individual arterial data at four points. Logan-distribution volume (V T/f P values obtained by cluster-IDIF were similar to reference results obtained using arterial data, as well as those obtained using manual-IDIF; 39 of 51 subjects had a V T/f P error of 10%. With automatic voxel selection, cluster-IDIF curves were less noisy than manual-IDIF and free of operator-related variability. Cluster-IDIF showed widespread decrease of about 20% [(11C](R-rolipram binding in the MDD group. Taken together, the results suggest that cluster-IDIF is a good alternative to full arterial input function for estimating Logan-V T/f P in [(11C](R-rolipram PET clinical scans. This

  14. Population-based input function modeling for [(18F]FMPEP-d 2, an inverse agonist radioligand for cannabinoid CB1 receptors: validation in clinical studies.

    Directory of Open Access Journals (Sweden)

    Paolo Zanotti-Fregonara

    Full Text Available BACKGROUND: Population-based input function (PBIF may be a valid alternative to full blood sampling for quantitative PET imaging. PBIF is typically validated by comparing its quantification results with those obtained via arterial sampling. However, for PBIF to be employed in actual clinical research studies, its ability to faithfully capture the whole spectrum of results must be assessed. The present study validated a PBIF for [(18F]FMPEP-d 2, a cannabinoid CB1 receptor radioligand, in healthy volunteers, and also attempted to utilize PBIF to replicate three previously published clinical studies in which the input function was acquired with arterial sampling. METHODS: The PBIF was first created and validated with data from 42 healthy volunteers. This PBIF was used to assess the retest variability of [(18F]FMPEP-d 2, and then to quantify CB1 receptors in alcoholic patients (n = 18 and chronic daily cannabis smokers (n = 29. Both groups were scanned at baseline and after 2-4 weeks of monitored drug abstinence. RESULTS: PBIF yielded accurate results in the 42 healthy subjects (average Logan-distribution volume (V T was 13.3±3.8 mL/cm(3 for full sampling and 13.2±3.8 mL/cm(3 for PBIF; R(2 = 0.8765, p<0.0001 and test-retest results were comparable to those obtained with full sampling (variability: 16%; intraclass correlation coefficient: 0.89. PBIF accurately replicated the alcoholism study, showing a widespread ∼20% reduction of CB1 receptors in alcoholic subjects, without significant change after abstinence. However, a small PBIF-V T bias of -9% was unexpectedly observed in cannabis smokers. This bias led to substantial errors, including a V T decrease in regions that had shown no downregulation in the full input function. Simulated data showed that the original findings could only have been replicated with a PBIF bias between -6% and +4%. CONCLUSIONS: Despite being initially well validated in healthy subjects, PBIF may

  15. Abdominal aortic aneurysm surgery

    DEFF Research Database (Denmark)

    Gefke, K; Schroeder, T V; Thisted, B

    1994-01-01

    The goal of this study was to identify patients who need longer care in the ICU (more than 48 hours) following abdominal aortic aneurysm (AAA) surgery and to evaluate the influence of perioperative complications on short- and long-term survival and quality of life. AAA surgery was performed in 553......, 78% stated that their quality of life had improved or was unchanged after surgery and had resumed working. These data justify a therapeutically aggressive approach, including ICU therapy following AAA surgery, despite failure of one or more organ systems....

  16. A computerized system for video analysis of the aortic valve.

    Science.gov (United States)

    Vesely, I; Menkis, A; Campbell, G

    1990-10-01

    A novel technique was developed to study the dynamic behavior of the porcine aortic valve in an isolated heart preparation. Under the control of a personal computer, a video frame grabber board continuously acquired and digitized images of the aortic valve, and an analog-to-digital (A/D) converter read four channels of physiological data (flow rate, aortic and ventricular pressure, and aortic root diameter). The valve was illuminated with a strobe light synchronized to fire at the field acquisition rate of the CCD video camera. Using the overlay bits in the video board, the measured parameters were super-imposed over the live video as graphical tracing, and the resultant composite images were recorded on-line to video tape. The overlaying of the valve images with the graphical tracings of acquired data enabled the data tracings to be precisely synchronized with the video images of the aortic valve. This technique enabled us to observe the relationship between aortic root expansion and valve function.

  17. Transcatheter aortic valve implantation vs. surgical aortic valve replacement for treatment of severe aortic stenosis

    DEFF Research Database (Denmark)

    Siontis, George C M; Praz, Fabien; Pilgrim, Thomas

    2016-01-01

    AIMS: In view of the currently available evidence from randomized trials, we aimed to compare the collective safety and efficacy of transcatheter aortic valve implantation (TAVI) vs. surgical aortic valve replacement (SAVR) across the spectrum of risk and in important subgroups. METHODS AND RESULTS...

  18. [Aortic valve replacement for the small aortic annulus].

    Science.gov (United States)

    Oshima, H; Usui, A; Akita, T; Ueda, Y

    2006-04-01

    Aortic valve surgery for the small aortic annulus is still challenging for surgeons. Recently, the new types of high performance prosthesis have been developed and the chance of an aortic root enlargement (ARE) is decreasing. In this study, we propose the ideal strategy of the aortic surgery for the small aortic annulus. We analyzed the clinical records of 158 patients who underwent aortic valve replacement from August 1999 to October 2005 in our institution. The small aortic annulus was observed in 38 patients (24%). Fourteen patients of this group underwent ARE. Patient-prosthesis mismatch (PPM) was less frequently observed in patients with ARE compared to those without ARE. The additional time required for ARE was not considerable, and neither ischemic time nor cardiopulmonary bypass time was significantly prolonged by ARE. In conclusion, we have to select a prosthesis with sufficient orifice area to avoid PPM, otherwise we should choose an option of ARE. For this consideration, we definitely need the chart that demonstrates the relationship between the nominal size of various types of prostheses and the size of a patient's annulus that those prostheses actually fit.

  19. Examination and clinical significance of coagulation function of patients with Type B Aortic Dissection%Stanford B型主动脉夹层动脉瘤患者凝血功能检测的意义

    Institute of Scientific and Technical Information of China (English)

    庞秀慧

    2011-01-01

    目的 探讨主动脉Stanford B型主动脉夹层动脉瘤(AD)患者凝血功能的变化及其临床意义.方法 2002-01-2011-01新疆维吾尔自治区人民医院收治Stanford B型主动脉夹层99例,选性别与年龄匹配的正常对照组95例,全自动血凝分析仪检测国际化标准比值(INR)、部分凝血活酶时间(APTT)、纤维蛋白原(FIB)和凝血酶时间(TT)、D-二聚体(DD).结果 AD组INR、APTT、FIB、DD均高于NC组,TT低于NC组,P<0.01.主动脉夹层分期内比较,亚急性及慢性组夹层INR、FIB高于急性期夹层组,APTT、DD、TT未见明显改变.结论 AD表现为凝血与纤溶持续激活,由于凝血与纤溶间的平衡破坏而产生高凝状态.%To explore the changes of blood coagulation function and clinical significances in type B aortic dissection( AD). Methods 99 patients with type B aortic dissection group,95 persons in healthy control group were selected respectively(NC) and the detection and analysis of international normalized ratio (INR), activated partial thromboplastin time(APTT),thrombin time(TT), fibrinogen(Fib) and D-dimer(D-D) were conducted. Results INR, APTT,FIB,DD in AD group significiantly increased compared with NC group,TT decreased respectively (P< 0. 01).Subact and chronic aortic dissection showed a significant increase in INR, Fib, compared with acute group. Conclusion AD is characterized by activation of both coagulation and fibrinolysis, resulting in an imbalance between coagulation and fibrinolysis leading to a hypercoagulation state.

  20. Valve-sparing aortic root replacement and aortic valve repair in a patient with acromegaly and aortic root dilatation

    Directory of Open Access Journals (Sweden)

    Karel Van Praet

    2015-07-01

    Full Text Available Aortic regurgitation and dilatation of the aortic root and ascending aorta are severe complications of acromegaly. The current trend for management of an aortic root aneurysm is valve-sparing root replacement as well as restoring the diameter of the aortic sinotubular junction (STJ and annulus. Our case report supports the recommendation that in patients with acromegaly, severe aortic root involvement may indicate the need for surgery.

  1. [Long-term results of conventional aortic valve replacement for small aortic annulus].

    Science.gov (United States)

    Miura, Y; Miyairi, T; Kitamura, T; Kigawa, I; Fukuda, S

    2006-04-01

    We studied cardiac function, clinical outcome and quality of life (QOL) long after aortic valve replacement for pure aortic stenosis. Forty-four patients in small group [St. Jude Medical (SJM) 17 HP, 19 A], and 69 patients in non-small group (19 HP, 21 A, 23 A) operated on from 1984 to 2004 were enrolled in this study. We assessed the clinical data, aortic pressure gradient, left ventricular mass index (LVMI), and ejection fraction (EF) by preoperative and postoperative echocardiography. Moreover to evaluate QOL after the operation, we performed SF-36 used for the evaluation of health and QOL worldwide. Mean follow-up is 7.1 +/- 4.8 years in small group, and 6.8 +/- 4.6 years in non-small group. There were 2 hospital deaths in small group, and 1 in non-small group. The actual survival rate at 10-year were 89.2% in small group, and 85.6% in non-small group. There was no significant difference in hospital mortality, LVMI, long-term survival rate, and the scores of SF-36 between the 2 groups. The use of small sized prosthetic valves in patients with small aortic annulus might be justified when there is no patient-prosthesis mismatch.

  2. Centrifugal pump support for distal aortic perfusion during repair of traumatic thoracic aortic injury.

    Science.gov (United States)

    Walls, Joseph T; Curtis, Jack J; McKenney-Knox, Charlotte A; Schmaltz, Richard A

    2002-11-01

    Paraplegia from ischemic injury of the spinal cord and renal failure from inadequate perfusion of the kidneys may occur from aortic cross-clamping during repair of traumatic thoracic aortic injuries. After Institutional Review Board approval, we retrospectively reviewed the charts of 26 patients surgically treated for traumatic transection of the descending thoracic aorta during a 14 year period (1987-2001), using centrifugal pump (Sarns) support for distal aortic perfusion. The study group comprised 19 males and 7 females, whose ages ranged from 15 to 69 years. For all but 1 patient, who fell from a flagpole, the injuries were incurred in motor vehicle accidents. Aortic cross-clamp time lasted between 5 to 78 min (median = 40 min). Mean arterial pressure ranged from 50 to 80 mm Hg (median = 70 mm Hg). All patients survived operation without developing paraplegia or renal failure. Distal centrifugal pump perfusion during repair of traumatic injury of the descending thoracic aorta is a valuable adjunct during surgical treatment and aids in preservation of spinal cord and renal function.

  3. Reinforced aortic root reconstruction for acute type A aortic dissection involving the aortic root

    Directory of Open Access Journals (Sweden)

    Han Qing-qi

    2013-06-01

    Full Text Available OBJECTIVE: There are debates regarding the optimal approach for AAAD involving the aortic root. We described a modified reinforced aortic root reconstruction approach for treating AAAD involving the aortic root. METHODS: A total of 161 patients with AAAD involving the aortic root were treated by our modified reinforced aortic root reconstruction approach from January 1998 to December 2008. Key features of our modified approach were placement of an autologous pericardial patch in the false lumen, lining of the sinotubular junction lumen with a polyester vascular ring, and wrapping of the vessel with Teflon strips. Outcome measures included post-operative mortality, survival, complications, and level of aortic regurgitation. RESULTS: A total of 161 patients were included in the study (mean age: 43.3 1 15.5 years. The mean duration of follow-up was 5.1 1 2.96 years (2-12 years. A total of 10 (6.2% and 11 (6.8% patients died during hospitalization and during follow-up, respectively. Thirty-one (19.3% patients experienced postoperative complications. The 1-, 3-, 5-, and 10-year survival rates were 99.3%, 98%, 93.8%, and 75.5%, respectively. There were no instances of recurrent aortic dissection, aortic aneurysm, or pseudoaneurysm during the entire study period. The severity of aortic regurgitation dramatically decreased immediately after surgery (from 28.6% to 0% grade 3-4 and thereafter slightly increased (from 0% to 7.2% at 5 years and 9.1% at 10 years. CONCLUSION: This modified reinforced aortic root reconstruction was feasible, safe and durable/effective, as indicated by its low mortality, low postoperative complications and high survival rate.

  4. Aortic Valve Replacement for Infective Endocarditis in a Renal Transplant Recipient

    Directory of Open Access Journals (Sweden)

    Masmoudi Sayda

    2000-01-01

    Full Text Available Renal transplant recipients are more prone to developing infections. We report a 37-year old renal transplant recipient who developed infective endocarditis of the aortic valve, heart failure and renal allograft dysfunction. He underwent aortic valve replacement which was followed by improvement in cardiac as well as allograft function.

  5. Clinical usefulness of the second peak of radial systolic blood pressure for estimation of aortic systolic blood pressure.

    Science.gov (United States)

    Kohara, K; Tabara, Y; Tomita, H; Nagai, T; Igase, M; Miki, T

    2009-08-01

    Central aortic blood pressure (BP), obtained from radial arterial waveform using the transfer function method (TFM), has been shown to have prognostic value independently of brachial BP. In this study, the relationship between peripheral systolic BP (SBP) and aortic SBP was evaluated. We further investigated whether TFM-derived aortic SBP can be estimated by information obtained from the radial waveform. The radial waveform was analysed to obtain the first peak of radial SBP (SBP1), second peak of radial SBP (SBP2), radial augmentation index (AI) (radial (SBP2-DBP)/(SBP1-DBP) x 100 and aortic SBP and AI using TFM in 233 subjects in the supine position. Measurements were repeated after changing position to the prone position. The constructed equation was validated in 149 community residents with different backgrounds. Radial SBP2 was closer to TFM-derived aortic SBP compared with brachial SBP. TFM-derived aortic SBP was approximated by the equation: aortic SBP=18.9-radial SBP2-0.03 x HR-0.214 x radial AI (r2=0.992). The equation was also applicable to predicting aortic SBP in the prone position as well as in different populations (mean difference between predicted aortic SBP and TFM-derived aortic SBP: -0.01+/-1.34 and 1.05+/-1.47 mm Hg, respectively). Radial arterial waveform analysis can be used for estimation of TFM-derived aortic SBP.

  6. Enhancing 4D PC-MRI in an aortic phantom considering numerical simulations

    Science.gov (United States)

    Kratzke, Jonas; Schoch, Nicolai; Weis, Christian; Müller-Eschner, Matthias; Speidel, Stefanie; Farag, Mina; Beller, Carsten J.; Heuveline, Vincent

    2015-03-01

    To date, cardiovascular surgery enables the treatment of a wide range of aortic pathologies. One of the current challenges in this field is given by the detection of high-risk patients for adverse aortic events, who should be treated electively. Reliable diagnostic parameters, which indicate the urge of treatment, have to be determined. Functional imaging by means of 4D phase contrast-magnetic resonance imaging (PC-MRI) enables the time-resolved measurement of blood flow velocity in 3D. Applied to aortic phantoms, three dimensional blood flow properties and their relation to adverse dynamics can be investigated in vitro. Emerging "in silico" methods of numerical simulation can supplement these measurements in computing additional information on crucial parameters. We propose a framework that complements 4D PC-MRI imaging by means of numerical simulation based on the Finite Element Method (FEM). The framework is developed on the basis of a prototypic aortic phantom and validated by 4D PC-MRI measurements of the phantom. Based on physical principles of biomechanics, the derived simulation depicts aortic blood flow properties and characteristics. The framework might help identifying factors that induce aortic pathologies such as aortic dilatation or aortic dissection. Alarming thresholds of parameters such as wall shear stress distribution can be evaluated. The combined techniques of 4D PC-MRI and numerical simulation can be used as complementary tools for risk-stratification of aortic pathology.

  7. NMDA currents modulate the synaptic input-output functions of neurons in the dorsal nucleus of the lateral lemniscus in Mongolian gerbils.

    Science.gov (United States)

    Porres, Christian P; Meyer, Elisabeth M M; Grothe, Benedikt; Felmy, Felix

    2011-03-23

    Neurons in the dorsal nucleus of the lateral lemniscus (DNLL) receive excitatory and inhibitory inputs from the superior olivary complex (SOC) and convey GABAergic inhibition to the contralateral DNLL and the inferior colliculi. Unlike the fast glycinergic inhibition in the SOC, this GABAergic inhibition outlasts auditory stimulation by tens of milliseconds. Two mechanisms have been postulated to explain this persistent inhibition. One, an "integration-based" mechanism, suggests that postsynaptic excitatory integration in DNLL neurons generates prolonged activity, and the other favors the synaptic time course of the DNLL output itself. The feasibility of the integration-based mechanism was tested in vitro in DNLL neurons of Mongolian gerbils by quantifying the cellular excitability and synaptic input-output functions (IO-Fs). All neurons were sustained firing and generated a near monotonic IO-F on current injections. From synaptic stimulations, we estimate that activation of approximately five fibers, each on average liberating ∼18 vesicles, is sufficient to trigger a single postsynaptic action potential. A strong single pulse of afferent fiber stimulation triggered multiple postsynaptic action potentials. The steepness of the synaptic IO-F was dependent on the synaptic NMDA component. The synaptic NMDA receptor current defines the slope of the synaptic IO-F by enhancing the temporal and spatial EPSP summation. Blocking this NMDA-dependent amplification during postsynaptic integration of train stimulations resulted into a ∼20% reduction of the decay time course of the GABAergic inhibition. Thus, our data show that the NMDA-dependent amplification of the postsynaptic activity contributes to the GABAergic persistent inhibition generated by DNLL neurons.

  8. Abdominal aortic aneurysms

    DEFF Research Database (Denmark)

    Lindholt, Jes Sanddal

    2010-01-01

    Although the number of elective operations for abdominal aortic aneurysms (AAA) is increasing, the sex- and age-standardised mortality rate of AAAs continues to rise, especially among men aged 65 years or more. The lethality of ruptured AAA continues to be 80-95%, compared with 5-7% by elective....... The acceptance rate was 77%, and 95% accept control scans. Furthermore, persons at the highest risk of having an AAA attend screening more frequently. We found that 97% of the interval cases developed from aortas that initially measured 2.5-2.9 cm - i.e. approx. only 5% attenders need re-screening at 5-year...... methods for measuring the degree of wall calcification must be developed and validated....

  9. CONGENITAL QUADRICUSPID AORTIC-VALVE

    NARCIS (Netherlands)

    BROUWER, MHJ; DEGRAAF, JJ; EBELS, T

    1993-01-01

    Two patients with a quadricuspid aortic valve are described, one of them with concomitant juxtaposed coronary orifices facing the right hand facing sinus. The etiology and incidence of this congenital anomaly will be discussed.

  10. Transcatheter Aortic Heart Valve Thrombosis

    DEFF Research Database (Denmark)

    Hansson, Nicolaj C; Grove, Erik L; Andersen, Henning R;

    2016-01-01

    BACKGROUND: There is increasing focus on transcatheter heart valve (THV) thrombosis. However, there are limited data on incidence, clinical implications and predisposing factors of THV thrombosis following transcatheter aortic valve replacement (TAVR). OBJECTIVES: We assessed the incidence...

  11. Adult thoracic and abdominal aortic

    Directory of Open Access Journals (Sweden)

    Randa O. Kaddah

    2016-06-01

    Conclusion: Aortic COA could be found in any segment of the aorta. Proper identification of the anatomical details and pressure gradient studies are important factors affecting the plan of management.

  12. Minimally invasive aortic valve replacement

    DEFF Research Database (Denmark)

    Foghsgaard, Signe; Schmidt, Thomas Andersen; Kjaergard, Henrik K

    2009-01-01

    In this descriptive prospective study, we evaluate the outcomes of surgery in 98 patients who were scheduled to undergo minimally invasive aortic valve replacement. These patients were compared with a group of 50 patients who underwent scheduled aortic valve replacement through a full sternotomy....... The 30-day mortality rate for the 98 patients was zero, although 14 of the 98 mini-sternotomies had to be converted to complete sternotomies intraoperatively due to technical problems. Such conversion doubled the operative time over that of the planned full sternotomies. In the group of patients whose...... is an excellent operation in selected patients, but its true advantages over conventional aortic valve replacement (other than a smaller scar) await evaluation by means of randomized clinical trial. The "extended mini-aortic valve replacement" operation, on the other hand, is a risky procedure that should...

  13. Intra-aortic balloon pump use does not affect the renal function in patients undergoing off pump coronary artery bypass surgery

    Directory of Open Access Journals (Sweden)

    Muniraju Geetha

    2011-01-01

    Full Text Available Renal dysfunction is known to occur during cardiac surgery. A few factors such as perioperative hypotension, use of potential nephrotoxic therapeutic agents, radio opaque contrast media in the recent past, intra-aortic balloon pump (IABP and cardiopulmonary bypass have been blamed as the contributing factors to the causation of postoperative renal dysfunction in cardiac surgical patients. At times, in patients with renal failure and low cardiac output status, one may face the dilemma if the use of IABP is safe. We undertook this prospective observational study to determine the degree of possible renal injury when IABP is used by measuring serial values of serum creatinine and Cystatin C. Elective patients scheduled for off-pump coronary artery bypass surgery requiring preoperative use of IABP were included in this study. Cystatin C and serum creatinine levels were checked at fixed intervals after institution of IABP. Twenty-two patients were eligible for enrolment to the study. There was no significant change in the values of serum creatinine; from the basal value of 1.10 ± 0.233 to 0.98 ± 0.363 mg /dL (P value >0.05. Cystatin C levels significantly decreased from the basal level of 0.98 ± 0.29 to 0.89 ± 0.23 (P value <0.05. Contrary to the belief, Cystatin C, the early indicator of renal dysfunction decreases suggesting absence of renal injury after the use of IABP. Absence of elevation of cystatin C levels in our study suggests the lack of potential of the IABP to cause renal dysfunction in patients who received elective IABP therapy preoperatively.

  14. Effect of an inelastic aortic synthetic vascular graft on exercise hemodynamics.

    Science.gov (United States)

    Kim, S Y; Hinkamp, T J; Jacobs, W R; Lichtenberg, R C; Posniak, H; Pifarré, R

    1995-04-01

    This study compared aortic input impedance characteristics between patients with aortic interposition Dacron grafts placed for traumatic aortic injury and normal age-matched control subjects. All subjects were examined at rest and after treadmill exercise. Magnetic resonance imaging was conducted to rule out anatomic (stenosis) effects. Exercise increased characteristic impedance (ie, reduced aortic distensibility) by 29% and decreased total systemic arterial compliance by 21% in the patient group, whereas the normal control group showed insignificant change in these variables after exercise. Peripheral pressure wave reflection was reduced substantially with exercise (27%) in the control group, with much less reduction observed in the patient group. These abnormal vascular hemodynamics were associated with significantly high cardiac energetic costs in the patient group. A plausible explanation for the observed differences lies in the exaggerated vascular impedance mismatch between compliant aorta and inelastic graft, when cardiac output increases dramatically.

  15. [New aspects in aortic valve disease].

    Science.gov (United States)

    Tornos, P

    2001-01-01

    Renewed interest for aortic valve disease has evolved in recent years. Aortic valve replacement has become the second most frequent cause of cardiac surgery, following coronary bypass surgery. In addition, the etiologic and physiopathologic knowledge of this disorder has improved. In the present paper we analyze three aspects of the disease which are, at present, the subject of study and controversy: first, we discuss the possible relationship between degenerative aortic stenosis and atherosclerosis; second, the involvement of the aortic root in cases of bicuspid aortic valve; and third, the surgical indications in asymptomatic patients with either aortic stenosis or regurgitation.

  16. [Management of aortic stenosis in patients undergoing non-cardiac surgery].

    Science.gov (United States)

    Labbé, Vincent; Ederhy, Stéphane; Szymkiewicz, Olga; Cohen, Ariel

    2015-01-01

    There is a significant risk of cardiovascular morbidity and mortality in patients with severe aortic stenosis (valve area angina, syncope, or heart failure). Before any surgery, clinical assessment should search for signs of aortic stenosis which justifies echocardiographic examination, particularly in the elderly. A systematic rest echocardiography with searching aortic stenosis should be considered in patients undergoing high risk surgery. The key points of pre-operative cardiac risk assessment are: assessment of the severity of aortic stenosis, measurement of the functional capacity, evaluation of the left ventricular systolic function, search of associated coronary artery disease, estimate of the surgical risk of cardiac events, and achievement of risk indices. In symptomatic patients with severe aortic stenosis, only urgent non-cardiac surgery should be performed under careful haemodynamic monitoring. Aortic valve replacement should be considered before elective non-cardiac surgery. In asymptomatic patients with severe aortic stenosis, aortic valve replacement should be considered before non-cardiac high risk surgery. Non-cardiac surgery at low/intermediate risk can be performed provided an adapted anaesthetic technique.

  17. Arterial input function of an optical tracer for dynamic contrast enhanced imaging can be determined from pulse oximetry oxygen saturation measurements

    Science.gov (United States)

    Elliott, Jonathan T.; Wright, Eric A.; Tichauer, Kenneth M.; Diop, Mamadou; Morrison, Laura B.; Pogue, Brian W.; Lee, Ting-Yim; St. Lawrence, Keith

    2012-12-01

    In many cases, kinetic modeling requires that the arterial input function (AIF)—the time-dependent arterial concentration of a tracer—be characterized. A straightforward method to measure the AIF of red and near-infrared optical dyes (e.g., indocyanine green) using a pulse oximeter is presented. The method is motivated by the ubiquity of pulse oximeters used in both preclinical and clinical applications, as well as the gap in currently available technologies to measure AIFs in small animals. The method is based on quantifying the interference that is observed in the derived arterial oxygen saturation (SaO2) following a bolus injection of a light-absorbing dye. In other words, the change in SaO2 can be converted into dye concentration knowing the chromophore-specific extinction coefficients, the true arterial oxygen saturation, and total hemoglobin concentration. A simple error analysis was performed to highlight potential limitations of the approach, and a validation of the method was conducted in rabbits by comparing the pulse oximetry method with the AIF acquired using a pulse dye densitometer. Considering that determining the AIF is required for performing quantitative tracer kinetics, this method provides a flexible tool for measuring the arterial dye concentration that could be used in a variety of applications.

  18. Determination of the arterial input function in mouse-models using clinical MRI; Bestimmung der arteriellen Inputfunktion in einem Mausmodell an einem klinischen MRT-System

    Energy Technology Data Exchange (ETDEWEB)

    Theis, D. [Philipps-Univ. Marburg (Germany). Klinik fuer Strahlendiagnostik; Fachhochschule Giessen-Friedberg (Germany). Inst. fuer Medizinische Physik und Strahlenschutz; Keil, B.; Heverhagen, J.T.; Klose, K.J. [Philipps-Univ. Marburg (Germany). Klinik fuer Strahlendiagnostik; Behe, M. [Philipps-Univ. Marburg (Germany). Klinik fuer Nuklearmedizin; Fiebich, M. [Fachhochschule Giessen-Friedberg (Germany). Inst. fuer Medizinische Physik und Strahlenschutz

    2008-07-01

    Dynamic contrast enhanced magnetic resonance imaging is a promising method for quantitative analysis of tumor perfusion and is increasingly used in study of cancer in small animal models. In those studies the determination of the arterial input function (AIF) of the target tissue can be the first step. Series of short-axis images of the heart were acquired during administration of a bolus of Gd-DTPA using saturation-recovery gradient echo pulse sequences. The AIF was determined from the changes of the signal intensity in the left ventricle. The native T1 relaxation times and AIF were determined for 11 mice. An average value of (1.16 {+-} 0.09) s for the native T1 relaxation time was measured. However, the AIF showed significant inter animal variability, as previously observed by other authors. The inter-animal variability shows, that a direct measurement of the AIF is reasonable to avoid significant errors. The proposed method for determination of the AIF proved to be reliable. (orig.)

  19. Image derived input function for [18F]-FEPPA: application to quantify translocator protein (18 kDa in the human brain.

    Directory of Open Access Journals (Sweden)

    Rostom Mabrouk

    Full Text Available In [18F]-FEPPA positron emission topography (PET imaging, automatic blood sampling system (ABSS is currently the gold standard to obtain the blood time activity curve (TAC required to extract the input function (IF. Here, we compare the performance of two image-based methods of IF extraction to the ABSS gold standard method for the quantification of translocator protein (TSPO in the human brain. The IFs were obtained from a direct delineation of the internal carotid signal (CS and a new concept of independent component analysis (ICA. PET scans were obtained from 18 healthy volunteers. The estimated total distribution volume (V(T by CS-IF and ICA-IF were compared to the reference V(T obtained by ABSS-IF in the frontal and temporal cortex, cerebellum, striatum and thalamus regions. The V(T values estimated using ICA-IF were more reliable than CS-IF for all brain regions. Specifically, the slope regression in the frontal cortex with ICA-IF was r² = 0.91 (p<0.05, and r² = 0.71 (p<0.05 using CS-IF.

  20. Exercise Hemodynamics and Quality of Life after Aortic Valve Replacement for Aortic Stenosis in the Elderly Using the Hancock II Bioprosthesis

    Science.gov (United States)

    Long, Theodore; Lopez, Becky M.; Berberian, Christopher; Cunningham, Mark J.; Starnes, Vaughn A.; Cohen, Robbin G.

    2014-01-01

    Background and Aim. While aortic valve replacement for aortic stenosis can be performed safely in elderly patients, there is a need for hemodynamic and quality of life evaluation to determine the value of aortic valve replacement in older patients who may have age-related activity limitation. Materials and Methods. We conducted a prospective evaluation of patients who underwent aortic valve replacement for aortic stenosis with the Hancock II porcine bioprosthesis. All patients underwent transthoracic echocardiography (TTE) and completed the RAND 36-Item Health Survey (SF-36) preoperatively and six months postoperatively. Results. From 2004 to 2007, 33 patients were enrolled with an average age of 75.3 ± 5.3 years (24 men and 9 women). Preoperatively, 27/33 (82%) were New York Heart Association (NYHA) Functional Classification 3, and postoperatively 27/33 (82%) were NYHA Functional Classification 1. Patients had a mean predicted maximum VO2 (mL/kg/min) of 19.5 ± 4.3 and an actual max VO2 of 15.5 ± 3.9, which was 80% of the predicted VO2. Patients were found to have significant improvements (P ≤ 0.01) in six of the nine SF-36 health parameters. Conclusions. In our sample of elderly patients with aortic stenosis, replacing the aortic valve with a Hancock II bioprosthesis resulted in improved hemodynamics and quality of life. PMID:25544931

  1. Novel pharmacological strategies to prevent aortic complications in Marfan syndrome

    Institute of Scientific and Technical Information of China (English)

    Peter Matt; Friedrich Eckstein

    2011-01-01

    The Marfan syndrome (MFS) is a systemic connective tissue disorder caused by mutations in the FBN1 gene.Recent molecular studies,most performed in mouse models,revealed that the MFS is more a developmental abnormality with broad and complex effects on the morphogenesis and function of multiple organ systems.FBN1 haploinsufficiency and dysregulated transforming growth factor-beta (TGF-β)signaling seem to be critical for clinical manifestations in MFS including aortic root dilatation.Aortic root aneurysm and aortic dissection represent the main causes of morbidity and mortality in MFS.Most importantly,TGF-β antagonism through angiotensin Ⅱ type 1 receptor blockers (ARBs),for example losartan,has been shown to prevent and possibly reverse aortic root dilatation in a mouse model of MFS.A first human study on a small pediatric cohort confirmed those promising results in reducing the aortic root growth over a follow-up period of 12 to 47 months.So,a large multicenter trial has been set up and results should be available soon.Other therapeutic strategies which might be combined with losartan include traditional β-blockade,doxycyclin and statins.Such management could offer the first potential for primary prevention of clinical manifestations in MFS.

  2. Midterm Results of Aortic Valve Replacement with Cryopreserved Homografts

    Directory of Open Access Journals (Sweden)

    Emre Özker

    2012-06-01

    Full Text Available Objective: The aim of this study was to analyze the midterm clinical results of aortic valve replacement with cryopreserved homografts.Materials and Methods: Aortic valve replacement was performed in 40 patients with cryopreserved homograft. The indications were aortic valve endocarditis in 20 patients (50%, truncus arteriosus in 6 patients (15%, and re-stenosis or regurtitation after aortic valve reconstruction in 14 (35% patients. The valve sizes ranged from 10 to 27mm. A full root replacement technique was used for homograft replacement in all patients.Results: The 30-day postoperative mortality rate was 12.5% (5 patients. There were four late deaths. Only one of them was related to cardiac events. Overall mortality was 22.5%. Thirty-three patients were followed up for 67±26 months. Two patients needed reoperation due to aortic aneurysm caused by endocarditis. The mean transvalvular gradient significantly decreased after valve replacement (p<0.003. The last follow up showed that the 27 (82% patients had a normal left ventricular function.Conclusion: Cryopreserved homografts are safe alternatives to mechanical valves that can be used when there are proper indications. Although it has a high perioperative mortality rate, cryopreserved homograft implantation is an alternative for valve replacement, particularly in younger patients and for complex surgical problems such as endocarditis that must be minimalized.

  3. Surrogate Markers of Abdominal Aortic Aneurysm Progression.

    Science.gov (United States)

    Wanhainen, Anders; Mani, Kevin; Golledge, Jonathan

    2016-02-01

    The natural course of many abdominal aortic aneurysms (AAA) is to gradually expand and eventually rupture and monitoring the disease progression is essential to their management. In this publication, we review surrogate markers of AAA progression. AAA diameter remains the most widely used and important marker of AAA growth. Standardized reporting of reproducible methods of measuring AAA diameter is essential. Newer imaging assessments, such as volume measurements, biomechanical analyses, and functional and molecular imaging, as well as circulating biomarkers, have potential to add important information about AAA progression. Currently, however, there is insufficient evidence to recommend their routine use in clinical practice.

  4. Prognostic importance of atrial fibrillation in asymptomatic aortic stenosis

    DEFF Research Database (Denmark)

    Greve, Anders; Gerdts, Eva; Boman, Kurt

    2013-01-01

    BACKGROUND: The frequency and prognostic importance of atrial fibrillation (AF) in asymptomatic mild-to-moderate aortic stenosis (AS) has not been well described. METHODS: Clinical examination, electrocardiography and echocardiography were obtained in asymptomatic patients with mild......-to-moderate AS and preserved left ventricular (LV) systolic function, randomized to simvastatin/ezetimibe combination vs. placebo in the Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) study. At inclusion, AF was categorized as episodic or longstanding. Rhythm change was assessed on annual in-study electrocardiograms...

  5. Quadricuspid aortic valve complicated with infective endocarditis: report of a case.

    Science.gov (United States)

    Mizoguchi, Hiroki; Sakaki, Masayuki; Inoue, Kazushige; Kobayashi, Yasuhiko; Iwata, Takashi; Suehiro, Yasuo; Miura, Takuya

    2014-12-01

    Congenital quadricuspid aortic valve is a rare cardiac malformation with an unknown risk of infective endocarditis. We report a case of quadricuspid aortic valve complicated with infective endocarditis. A 53-year-old Japanese woman was hospitalized with leg edema and a fever of unknown origin. Corynebacterium striatum was detected in the blood culture. Echocardiography demonstrated a quadricuspid aortic valve with vegetation and severe functional regurgitation. The condition was diagnosed as a quadricuspid aortic valve with infective endocarditis, for which surgery was performed. The quadricuspid aortic valve had three equal-sized cusps and one smaller cusp (type B according to Hurwitz classification). We dissected the vegetation and infectious focus and implanted a mechanical valve. Following the case report, we review the literature.

  6. Abdominal aortic aneurysm repair - open - discharge

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000240.htm Abdominal aortic aneurysm repair - open - discharge To use the sharing features ... References Orandi BJ, Black JH. Open repair of abdominal aortic aneurysms. In: Cameron JL, Cameron AM, eds. Current Surgical ...

  7. Impact of Endografting on the Thoracic Aortic Anatomy: Comparative Analysis of the Aortic Geometry before and after the Endograft Implantation

    Energy Technology Data Exchange (ETDEWEB)

    Midulla, Marco, E-mail: marco.midulla@chru-lille.fr [University Hospital of Lille, Cardiovascular and Interventional Radiology (France); Moreno, Ramiro, E-mail: ramoroa@gmail.com [Rangueil University Hospital, Department of Radiology (France); Negre-Salvayre, Anne, E-mail: anne.negre-salvayre@inserm.fr [INSERM, UMR 1048, I2MC (France); Nicoud, Franc, E-mail: franck.nicoud@univ-montp2.fr [CNRS, UMR 5149 I3M, CC 051, University Montpellier II (France); Pruvo, Jean Pierre, E-mail: jean-pierre.pruvo@chru-lille.fr [University Hospital of Lille, Cardiovascular and Interventional Radiology (France); Haulon, Stephan, E-mail: stephan.haulon@chru-lille.fr [University Hospital of Lille, Department of Vascular Surgery (France); Rousseau, Hervé, E-mail: rousseau.h@chu-toulouse.fr [Rangueil University Hospital, Department of Radiology (France)

    2013-03-13

    PurposeAlthough the widespread acceptance of thoracic endovascular aortic repair (TEVAR) as a first-line treatment option for a multitude of thoracic aortic diseases, little is known about the consequences of the device implantation on the native aortic anatomy. We propose a comparative analysis of the pre- and postoperative geometry on a clinical series of patients and discuss the potential clinical implicationsMethodsCT pre- and postoperative acquisitions of 30 consecutive patients treated by TEVAR for different pathologies (20 thoracic aortic aneurysms, 6 false aneurysms, 3 penetrating ulcers, 1 traumatic rupture) were used to model the vascular geometry. Pre- and postoperative geometries were compared for each patient by pairing and matching the 3D models. An implantation site was identified, and focal differences were detected and described.ResultsSegmentation of the data sets was successfully performed for all 30 subjects. Geometry differences between the pre- and postoperative meshes were depicted in 23 patients (76 %). Modifications at the upper implantation site were detected in 14 patients (47 %), and among them, the implantation site involved the arch (Z0–3) in 11 (78 %).ConclusionModeling the vascular geometry on the basis of imaging data offers an effective tool to perform patient-specific analysis of the vascular geometry before and after the treatment. Future studies will evaluate the consequences of these changes on the aortic function.

  8. Management of bicuspid aortic valve with or without involvement of ascending aorta and aortic root.

    Science.gov (United States)

    Neragi-Miandoab, S

    2014-06-01

    Patients with a bicuspid aortic valve (BAV) constitute a heterogeneous population with variable clinical presentation and complications. More than 50% of the patients who require aortic valve replacement have a BAV, a condition that may be associated with dilation of ascending aorta and aortic insufficiency caused by cusp disease or aortic root pathology. Of the potential BAV-related complications, dilation of the aortic root and ascending aorta are among the most serious. The dilation of ascending aorta and aortic root have been the subject of controversy. Whereas some surgeons believe that the dilation of the aorta is caused by the hemodynamic properties of the BAV, others believe that the dilation of the aortic root is secondary to genetic defects associated with the BAV. Management of a BAV should be tailored to each patient's clinical condition. The surgical approach varies from aortic valve replacement to combined aortic valve and root replacement to aortic-valve-sparing root replacement.

  9. Abdominal aortic feminism.

    Science.gov (United States)

    Mortimer, Alice Emily

    2014-01-01

    A 79-year-old woman presented to a private medical practice 2 years previously for an elective ultrasound screening scan. This imaging provided the evidence for a diagnosis of an abdominal aortic aneurysm (AAA) to be made. Despite having a number of recognised risk factors for an AAA, her general practitioner at the time did not follow the guidance set out by the private medical professional, that is, to refer the patient to a vascular specialist to be entered into a surveillance programme and surgically evaluated. The patient became symptomatic with her AAA, was admitted to hospital and found to have a tender, symptomatic, 6 cm leaking AAA. She consented for an emergency open AAA repair within a few hours of being admitted to hospital, despite the 50% perioperative mortality risk. The patient spent 4 days in intensive care where she recovered well. She was discharged after a 12 day hospital stay but unfortunately passed away shortly after her discharge from a previously undiagnosed gastric cancer.

  10. Open aortic surgery after thoracic endovascular aortic repair.

    Science.gov (United States)

    Coselli, Joseph S; Spiliotopoulos, Konstantinos; Preventza, Ourania; de la Cruz, Kim I; Amarasekara, Hiruni; Green, Susan Y

    2016-08-01

    In the last decade, thoracic endovascular aortic aneurysm repair (TEVAR) has emerged as an appealing alternative to the traditional open aortic aneurysm repair. This is largely due to generally improved early outcomes associated with TEVAR, including lower perioperative mortality and morbidity. However, it is relatively common for patients who undergo TEVAR to need a secondary intervention. In select circumstances, these secondary interventions are performed as an open procedure. Although it is difficult to assess the rate of open repairs after TEVAR, the rates in large series of TEVAR cases (>300) have ranged from 0.4 to 7.9 %. Major complications of TEVAR that typically necessitates open distal aortic repair (i.e., repair of the descending thoracic or thoracoabdominal aorta) include endoleak (especially type I), aortic fistula, endograft infection, device collapse or migration, and continued expansion of the aneurysm sac. Conversion to open repair of the distal aorta may be either elective (as for many endoleaks) or emergent (as for rupture, retrograde complicated dissection, malperfusion, and endograft infection). In addition, in select patients (e.g., those with a chronic aortic dissection), unrepaired sections of the aorta may progressively dilate, resulting in the need for multiple distal aortic repairs. Open repairs after TEVAR can be broadly classified as full extraction, partial extraction, or full salvage of the stent-graft. Although full and partial stent-graft extraction imply failure of TEVAR, such failure is generally absent in cases where the stent-graft can be fully salvaged. We review the literature regarding open repair after TEVAR and highlight operative strategies.

  11. Prognostic importance of atrial fibrillation in asymptomatic aortic stenosis: The Simvastatin and Ezetimibe in Aortic Stenosis study

    DEFF Research Database (Denmark)

    Greve, Anders M; Gerdts, Eva; Boman, Kurt

    2011-01-01

    BACKGROUND: The frequency and prognostic importance of atrial fibrillation (AF) in asymptomatic mild-to-moderate aortic stenosis (AS) has not been well described. METHODS: Clinical examination, electrocardiography and echocardiography were obtained in asymptomatic patients with mild......-to-moderate AS and preserved left ventricular (LV) systolic function, randomized to simvastatin/ezetimibe combination vs. placebo in the Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) study. At inclusion, AF was categorized as episodic or longstanding. Rhythm change was assessed on annual in-study electrocardiograms...

  12. Aortic or Mitral Valve Replacement With the Biocor and Biocor Supra

    Science.gov (United States)

    2016-03-09

    Aortic Valve Insufficiency; Aortic Valve Regurgitation; Aortic Valve Stenosis; Aortic Valve Incompetence; Mitral Valve Insufficiency; Mitral Valve Regurgitation; Mitral Valve Stenosis; Mitral Valve Incompetence

  13. A model-constrained Monte Carlo method for blind arterial input function estimation in dynamic contrast-enhanced MRI: II. In vivo results

    Science.gov (United States)

    Schabel, Matthias C.; DiBella, Edward V. R.; Jensen, Randy L.; Salzman, Karen L.

    2010-08-01

    Accurate quantification of pharmacokinetic model parameters in tracer kinetic imaging experiments requires correspondingly accurate determination of the arterial input function (AIF). Despite significant effort expended on methods of directly measuring patient-specific AIFs in modalities as diverse as dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), dynamic positron emission tomography (PET), and perfusion computed tomography (CT), fundamental and technical difficulties have made consistent and reliable achievement of that goal elusive. Here, we validate a new algorithm for AIF determination, the Monte Carlo blind estimation (MCBE) method (which is described in detail and characterized by extensive simulations in a companion paper), by comparing AIFs measured in DCE-MRI studies of eight brain tumor patients with results of blind estimation. Blind AIFs calculated with the MCBE method using a pool of concentration-time curves from a region of normal brain tissue were found to be quite similar to the measured AIFs, with statistically significant decreases in fit residuals observed in six of eight patients. Biases between the blind and measured pharmacokinetic parameters were the dominant source of error. Averaged over all eight patients, the mean biases were +7% in K trans, 0% in kep, -11% in vp and +10% in ve. Corresponding uncertainties (median absolute deviation from the best fit line) were 0.0043 min-1 in K trans, 0.0491 min-1 in kep, 0.29% in vp and 0.45% in ve. The use of a published population-averaged AIF resulted in larger mean biases in three of the four parameters (-23% in K trans, -22% in kep, -63% in vp), with the bias in ve unchanged, and led to larger uncertainties in all four parameters (0.0083 min-1 in K trans, 0.1038 min-1 in kep, 0.31% in vp and 0.95% in ve). When blind AIFs were calculated from a region of tumor tissue, statistically significant decreases in fit residuals were observed in all eight patients despite larger

  14. Corrections of arterial input function for dynamic H215O PET to assess perfusion of pelvic tumours: arterial blood sampling versus image extraction

    Science.gov (United States)

    Lüdemann, L.; Sreenivasa, G.; Michel, R.; Rosner, C.; Plotkin, M.; Felix, R.; Wust, P.; Amthauer, H.

    2006-06-01

    Assessment of perfusion with 15O-labelled water (H215O) requires measurement of the arterial input function (AIF). The arterial time activity curve (TAC) measured using the peripheral sampling scheme requires corrections for delay and dispersion. In this study, parametrizations with and without arterial spillover correction for fitting of the tissue curve are evaluated. Additionally, a completely noninvasive method for generation of the AIF from a dynamic positron emission tomography (PET) acquisition is applied to assess perfusion of pelvic tumours. This method uses a volume of interest (VOI) to extract the TAC from the femoral artery. The VOI TAC is corrected for spillover using a separate tissue TAC and for recovery by determining the recovery coefficient on a coregistered CT data set. The techniques were applied in five patients with pelvic tumours who underwent a total of 11 examinations. Delay and dispersion correction of the blood TAC without arterial spillover correction yielded in seven examinations solutions inconsistent with physiology. Correction of arterial spillover increased the fitting accuracy and yielded consistent results in all patients. Generation of an AIF from PET image data was investigated as an alternative to arterial blood sampling and was shown to have an intrinsic potential to determine the AIF noninvasively and reproducibly. The AIF extracted from a VOI in a dynamic PET scan was similar in shape to the blood AIF but yielded significantly higher tissue perfusion values (mean of 104.0 ± 52.0%) and lower partition coefficients (-31.6 ± 24.2%). The perfusion values and partition coefficients determined with the VOI technique have to be corrected in order to compare the results with those of studies using a blood AIF.

  15. Aortic root replacement with a pulmonary autograft

    NARCIS (Netherlands)

    R.B. Hokken (Raymond)

    1997-01-01

    textabstractAortic valve disease in the pediatric age group is usually a consequence of congenital aortic stenosis, which may be isolated or may be a part of an anomaly of the left ventricular outflow tract or the aortic root. Management of these patients is difficult. Neonates and infants with seve

  16. [MINIMALLY INVASIVE AORTIC VALVE REPLACEMENT].

    Science.gov (United States)

    Tabata, Minoru

    2016-03-01

    Minimally invasive aortic valve replacement (MIAVR) is defined as aortic valve replacement avoiding full sternotomy. Common approaches include a partial sternotomy right thoracotomy, and a parasternal approach. MIAVR has been shown to have advantages over conventional AVR such as shorter length of stay and smaller amount of blood transfusion and better cosmesis. However, it is also known to have disadvantages such as longer cardiopulmonary bypass and aortic cross-clamp times and potential complications related to peripheral cannulation. Appropriate patient selection is very important. Since the procedure is more complex than conventional AVR, more intensive teamwork in the operating room is essential. Additionally, a team approach during postoperative management is critical to maximize the benefits of MIAVR.

  17. Abdominal aortic surgery and renal anomalies

    Directory of Open Access Journals (Sweden)

    Ilić Nikola

    2011-01-01

    Full Text Available Introduction. Kidney anomalies present a challenge even for the most experienced vascular surgeon in the reconstruction of the aortoilliac segment. The most significant anomalies described in the surgery of the aortoilliac segment are a horse-shoe and ectopic kidney. Objective. The aim of this retrospective study was to analyze experience on 40 patients with renal anomalies, who underwent surgery of the aortoilliac segment and to determine attitudes on conventional surgical treatment. Methods. In the period from 1992 to 2009, at the Clinic for Vascular Surgery of the Clinical Centre of Belgrade we operated on 40 patients with renal anomalies and aortic disease (aneurysmatic and obstructive. The retrospective analysis involved standard epidemiological data of each patient (gender, age, risk factors for atherosclerosis, type of anomaly, type of aortic disease, presurgical parameter values of renal function, type of surgical approach (laparatomy or retroperitoneal approach, classification of the renal isthmus, reimplantation of renal arteries and perioperative morbidity and mortality. Results. Twenty patients were males In 30 (70% patients we diagnosed a horse-shoe kidney and in 10 (30% ectopic kidney. In the cases of ruptured aneurysm of the abdominal aorta the diagnosis was made by ultrasound findings. Pre-surgically, renal anomalies were confirmed in all patients, except in those with a ruptured aneurysm who underwent urgent surgery. In all patients we applied medial laparatomy, except in those with a thoracoabdominal aneurysm type IV, when the retroperitonal approach was necessary. On average the patients were under follow-up for 6.2 years (from 6 months to 17 years. Conclusion. Under our conditions, the so-called double clamp technique with the preservation of the kidney gave best results in the patients with renal anomalies and aortic disease.

  18. Transfemoral transcatheter aortic valve implantation in a patient with a severe aortic stenosis and cardiogenic shock requiring intra-aortic balloon pump support.

    Science.gov (United States)

    Chodór, Piotr; Wilczek, Krzysztof; Przybylski, Roman; Świątkowski, Andrzej; Głowacki, Jan; Kalarus, Zbigniew; Zembala, Marian

    2015-01-01

    The following paper presents a patient with severe aortic stenosis and severely reduced left ventricular ejection fraction with intra-aortic balloon pump counterpulsation support, who underwent transfemoral aortic valve implantation of a CoreValve prosthesis.

  19. Transfemoral transcatheter aortic valve implantation in a patient with a severe aortic stenosis and cardiogenic shock requiring intra-aortic balloon pump support

    OpenAIRE

    Chodór, Piotr; Wilczek, Krzysztof; Przybylski, Roman; Świątkowski, Andrzej; Głowacki, Jan; Kalarus, Zbigniew; Zembala, Marian

    2015-01-01

    The following paper presents a patient with severe aortic stenosis and severely reduced left ventricular ejection fraction with intra-aortic balloon pump counterpulsation support, who underwent transfemoral aortic valve implantation of a CoreValve prosthesis.

  20. Genetic and Epigenetic Regulation of Aortic Aneurysms

    Science.gov (United States)

    Kim, Ha Won

    2017-01-01

    Aneurysms are characterized by structural deterioration of the vascular wall leading to progressive dilatation and, potentially, rupture of the aorta. While aortic aneurysms often remain clinically silent, the morbidity and mortality associated with aneurysm expansion and rupture are considerable. Over 13,000 deaths annually in the United States are attributable to aortic aneurysm rupture with less than 1 in 3 persons with aortic aneurysm rupture surviving to surgical intervention. Environmental and epidemiologic risk factors including smoking, male gender, hypertension, older age, dyslipidemia, atherosclerosis, and family history are highly associated with abdominal aortic aneurysms, while heritable genetic mutations are commonly associated with aneurysms of the thoracic aorta. Similar to other forms of cardiovascular disease, family history, genetic variation, and heritable mutations modify the risk of aortic aneurysm formation and provide mechanistic insight into the pathogenesis of human aortic aneurysms. This review will examine the relationship between heritable genetic and epigenetic influences on thoracic and abdominal aortic aneurysm formation and rupture. PMID:28116311

  1. Aortic Root Enlargement or Sutureless Valve Implantation?

    Directory of Open Access Journals (Sweden)

    Nikolaos G. Baikoussis

    2016-11-01

    Full Text Available Aortic valve replacement (AVR in patients with a small aortic annulus is a challenging issue. The importance of prosthesis–patient mismatch (PPM post aortic valve replacement (AVR is controversial but has to be avoided. Many studies support the fact that PPM has a negative impact on short and long term survival. In order to avoid PPM, aortic root enlargement may be performed. Alternatively and keeping in mind that often some comorbidities are present in old patients with small aortic root, the Perceval S suturelles valve implantation could be a perfect solution. The Perceval sutureless bioprosthesis provides reasonable hemodynamic performance avoiding the PPM and providing the maximum of aortic orifice area. We would like to see in the near future the role of the aortic root enlargement techniques in the era of surgical implantation of the sutureless valve (SAVR and the transcatheter valve implantation (TAVI.

  2. Aortic Wall Injury Related to Endovascular Therapy for Aortic Coarctation.

    Science.gov (United States)

    Tretter, Justin T; Jones, Thomas K; McElhinney, Doff B

    2015-09-01

    Aortic wall complications can occur in unrepaired aortic coarctation (CoA) and after surgical repair or endovascular treatment. This review summarizes the available literature and current understanding of aortic wall injury (AWI) surrounding the management of CoA, focusing specifically on acute and follow-up AWI after endovascular treatment. There have been 23 reported cases of aortic rupture after endovascular treatment for CoA, including angioplasty alone, bare metal stenting, and primary covered stent therapy. Even if these published cases represent only a minority of ruptures that have actually occurred, the incidence is substantially <1%. The incidence of acute aneurysm formation was 0% to 13% after angioplasty, 0% to 5% after bare metal stent placement, and <1% after covered stent placement. The reported incidence and natural history of both acute and new AWI during follow-up after endovascular therapy for CoA varies considerably, likely secondary to ascertainment and reporting biases and inconsistent definitions. Although important AWI after endovascular treatment of CoA seems to be declining in frequency with increasing experience and improving technology, it remains one of the most important potential adverse outcomes. Long-term surveillance for new AWI and monitoring of existing AWI is mandatory, with institution of appropriate treatment when necessary. A central research focus in this population should be determination of the appropriate treatment for both native and recurrent CoA across various ages with regard to limiting recurrent CoA and preventing associated aortic wall complications, in addition to determining the appropriate treatment of various AWI. Consistent definitions and reporting are necessary to truly understand the incidence of, risk factors for, and measures protective against AWI after angioplasty or stent implantation for CoA.

  3. A model-constrained Monte Carlo method for blind arterial input function estimation in dynamic contrast-enhanced MRI: I. Simulations.

    Science.gov (United States)

    Schabel, Matthias C; Fluckiger, Jacob U; DiBella, Edward V R

    2010-08-21

    Widespread adoption of quantitative pharmacokinetic modeling methods in conjunction with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has led to increased recognition of the importance of obtaining accurate patient-specific arterial input function (AIF) measurements. Ideally, DCE-MRI studies use an AIF directly measured in an artery local to the tissue of interest, along with measured tissue concentration curves, to quantitatively determine pharmacokinetic parameters. However, the numerous technical and practical difficulties associated with AIF measurement have made the use of population-averaged AIF data a popular, if sub-optimal, alternative to AIF measurement. In this work, we present and characterize a new algorithm for determining the AIF solely from the measured tissue concentration curves. This Monte Carlo blind estimation (MCBE) algorithm estimates the AIF from the subsets of D concentration-time curves drawn from a larger pool of M candidate curves via nonlinear optimization, doing so for multiple (Q) subsets and statistically averaging these repeated estimates. The MCBE algorithm can be viewed as a generalization of previously published methods that employ clustering of concentration-time curves and only estimate the AIF once. Extensive computer simulations were performed over physiologically and experimentally realistic ranges of imaging and tissue parameters, and the impact of choosing different values of D and Q was investigated. We found the algorithm to be robust, computationally efficient and capable of accurately estimating the AIF even for relatively high noise levels, long sampling intervals and low diversity of tissue curves. With the incorporation of bootstrapping initialization, we further demonstrated the ability to blindly estimate AIFs that deviate substantially in shape from the population-averaged initial guess. Pharmacokinetic parameter estimates for K(trans), k(ep), v(p) and v(e) all showed relative biases and

  4. Remodelling of the aortic root in severe tricuspid aortic stenosis: implications for transcatheter aortic valve implantation

    Energy Technology Data Exchange (ETDEWEB)

    Stolzmann, Paul; Desbiolles, Lotus; Scheffel, Hans; Leschka, Sebastian; Marincek, Borut; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Knight, Joseph; Kurtcuoglu, Vartan; Poulikakos, Dimos [Laboratory of Thermodynamics in Emerging Technologies, Department of Mechanical and Process Engineering, ETH Zurich (Switzerland); Maier, Willibald [University Hospital Zurich, Cardiovascular Center, Zurich (Switzerland); Plass, Andre [University Hospital Zurich, Clinic for Cardiovascular Surgery, Zurich (Switzerland)

    2009-06-15

    Detailed knowledge of aortic root geometry is a prerequisite to anticipate complications of transcatheter aortic valve (TAV) implantation. We determined coronary ostial locations and aortic root dimensions in patients with aortic stenosis (AS) and compared these values with normal subjects using computed tomography (CT). One hundred consecutive patients with severe tricuspid AS and 100 consecutive patients without valvular pathology (referred to as the controls) undergoing cardiac dual-source CT were included. Distances from the aortic annulus (AA) to the left coronary ostium (LCO), right coronary ostium (RCO), the height of the left coronary sinus (HLS), right coronary sinus (HRS), and aortic root dimensions [diameters of AA, sinus of Valsalva (SV), and sino-tubular junction(STJ)] were measured. LCO and RCO were 14.9 {+-} 3.2 mm (8.2-25.9) and 16.8 {+-} 3.6 mm (12.0-25.7) in the controls, 15.5 {+-} 2.9 mm (8.8-24.3) and 17.3 {+-} 3.6 mm (7.3-26.0) in patients with AS. Controls and patients with AS had similar values for LCO (P = 0.18), RCO (P = 0.33) and HLS (P = 0.88), whereas HRS (P < 0.05) was significantly larger in patients with AS. AA (r = 0.55,P < 0.001), SV (r = 0.54,P < 0.001), and STJ (r = 0.52,P < 0.001) significantly correlated with the body surface area in the controls; whereas no correlation was found in patients with AS. Patients with AS had significantly larger AA (P < 0.01) and STJ (P < 0.01) diameters when compared with the controls. In patients with severe tricuspid AS, coronary ostial locations were similar to the controls, but a transverse remodelling of the aortic root was recognized. Owing to the large distribution of ostial locations and the dilatation of the aortic root, CT is recommended before TAV implantation in each patient. (orig.)

  5. Spectrum of Aortic Valve Abnormalities Associated with Aortic Dilation Across Age Groups in Turner Syndrome

    Science.gov (United States)

    Olivieri, Laura J.; Baba, Ridhwan Y.; Arai, Andrew E.; Bandettini, W. Patricia; Rosing, Douglas R.; Bakalov, Vladimir; Sachdev, Vandana; Bondy, Carolyn A.

    2014-01-01

    Background Congenital aortic valve fusion is associated with aortic dilation, aneurysm and rupture in girls and women with Turner syndrome (TS). Our objective was to characterize aortic valve structure in subjects with TS, and determine the prevalence of aortic dilation and valve dysfunction associated with different types of aortic valves. Methods and Results The aortic valve and thoracic aorta were characterized by cardiovascular magnetic resonance imaging in 208 subjects with TS in an IRB-approved natural history study. Echocardiography was used to measure peak velocities across the aortic valve, and the degree of aortic regurgitation. Four distinct valve morphologies were identified: tricuspid aortic valve (TAV) 64%(n=133), partially fused aortic valve (PF) 12%(n=25), bicuspid aortic valve (BAV) 23%(n=47), and unicuspid aortic valve (UAV) 1%(n=3). Age and body surface area (BSA) were similar in the 4 valve morphology groups. There was a significant trend, independent of age, towards larger BSA-indexed ascending aortic diameters (AADi) with increasing valve fusion. AADi were (mean +/− SD) 16.9 +/− 3.3 mm/m2, 18.3 +/− 3.3 mm/m2, and 19.8 +/− 3.9 mm/m2 (p<0.0001) for TAV, PF and BAV+UAV respectively. PF, BAV, and UAV were significantly associated with mild aortic regurgitation and elevated peak velocities across the aortic valve. Conclusions Aortic valve abnormalities in TS occur with a spectrum of severity, and are associated with aortic root dilation across age groups. Partial fusion of the aortic valve, traditionally regarded as an acquired valve problem, had an equal age distribution and was associated with an increased AADi. PMID:24084490

  6. In vitro study of the aortic interleaflet triangle reshaping.

    Science.gov (United States)

    Vismara, R; Leopaldi, A M; Mangini, A; Romagnoni, C; Contino, M; Antona, C; Fiore, G B

    2014-01-22

    Aortic interleaflet triangle reshaping (AITR) is a surgical approach to aortic valve incontinence that involves placing three stitches at half of the interleaflet triangles height. In this work, the relationship between the actual stitch height and valve functioning, and the safety margin that the surgeon can rely on in applying the stitches were systematically investigated in vitro. AITR surgery was applied to six swine aortic roots placing the stitches empirically at 50%, 60% and 75% of the triangle heights. Then the actual stitch heights were measured and the hydrodynamic performances were evaluated with a pulsatile hydrodynamic mock loop. Actual stitch heights were 45±2%, 61±4% and 79±6%. As compared to untreated conditions, the 50% configuration induced a significant variation in the effective orifice area. With stitches placed at 60%, the mean systolic pressure drop increased significantly with respect to the untreated case, but no significant changes were recorded with respect to the 50% configuration. At 75%, all the hydrodynamic parameters of systolic valve functioning worsened significantly. Summarizing, the AITR technique, when performed in a conservative manner did not induce significant alterations in the hydrodynamics of the aortic root in vitro, while more aggressive configurations did. The absence of a statistically significant difference between the 50% and 60% configurations suggests that there is a reasonably limited risk of inducing valve stenosis in the post-op scenario due to stitch misplacement.

  7. SU-C-18C-02: Specifcation of X-Ray Projection Angles Which Are Aligned with the Aortic Valve Plane From a Planar Image of a Valvuloplasty Balloon Inflated Across the Aortic Valve

    Energy Technology Data Exchange (ETDEWEB)

    Fetterly, K; Mathew, V [Mayo Clinic, Rochester, MN (United States)

    2014-06-01

    Purpose: Transcatheter aortic valve replacement (TAVR) procedures provide a method to implant a prosthetic aortic valve via a minimallyinvasive, catheter-based procedure. TAVR procedures require use of interventional fluoroscopy c-arm projection angles which are aligned with the aortic valve plane to minimize prosthetic valve positioning error due to x-ray imaging parallax. The purpose of this work is to calculate the continuous range of interventional fluoroscopy c-arm projection angles which are aligned with the aortic valve plane from a single planar image of a valvuloplasty balloon inflated across the aortic valve. Methods: Computational methods to measure the 3D angular orientation of the aortic valve were developed. Required inputs include a planar x-ray image of a known valvuloplasty balloon inflated across the aortic valve and specifications of x-ray imaging geometry from the DICOM header of the image. A-priori knowledge of the species-specific typical range of aortic orientation is required to specify the sign of the angle of the long axis of the balloon with respect to the x-ray beam. The methods were validated ex-vivo and in a live pig. Results: Ex-vivo experiments demonstrated that the angular orientation of a stationary inflated valvuloplasty balloon can be measured with precision less than 1 degree. In-vivo pig experiments demonstrated that cardiac motion contributed to measurement variability, with precision less than 3 degrees. Error in specification of x-ray geometry directly influences measurement accuracy. Conclusion: This work demonstrates that the 3D angular orientation of the aortic valve can be calculated precisely from a planar image of a valvuloplasty balloon inflated across the aortic valve and known x-ray geometry. This method could be used to determine appropriate c-arm angular projections during TAVR procedures to minimize x-ray imaging parallax and thereby minimize prosthetic valve positioning errors.

  8. Successes and challenges of using whole exome sequencing to identify novel genes underlying an inherited predisposition for thoracic aortic aneurysms and acute aortic dissections.

    Science.gov (United States)

    Milewicz, Dianna M; Regalado, Ellen S; Shendure, Jay; Nickerson, Deborah A; Guo, Dong-chuan

    2014-02-01

    Thoracic aortic aneurysms involving the aortic root and/or ascending aorta can lead to acute aortic dissections. Approximately 20% of patients with thoracic aortic aneurysms and dissections (TAAD) have a family history of the disease, referred to as familial TAAD (FTAAD) that can be inherited in an autosomal dominant manner with variable expression with respect to disease presentation, age of onset and associated features. Whole exome sequencing (WES) has been used to identify causative mutations in novel genes for TAAD. The strategy used to reduce the large number of rare variants identified using WES is to sequence distant relatives with TAAD and filter for heterozygous rare variants that are shared between the relatives, predicted to disrupt protein function and segregate with the TAAD phenotype in other family members. Putative genes are validated by identifying additional families with a causative mutation in the genes. This approach has successfully identified novel genes for FTAAD.

  9. Statins for aortic valve stenosis

    Directory of Open Access Journals (Sweden)

    Luciana Thiago

    Full Text Available ABSTRACT BACKGROUND: Aortic valve stenosis is the most common type of valvular heart disease in the USA and Europe. Aortic valve stenosis is considered similar to atherosclerotic disease. Some studies have evaluated statins for aortic valve stenosis. OBJECTIVES: To evaluate the effectiveness and safety of statins in aortic valve stenosis. METHODS: Search methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL, MEDLINE, Embase, LILACS - IBECS, Web of Science and CINAHL Plus. These databases were searched from their inception to 24 November 2015. We also searched trials in registers for ongoing trials. We used no language restrictions. Selection criteria: Randomized controlled clinical trials (RCTs comparing statins alone or in association with other systemic drugs to reduce cholesterol levels versus placebo or usual care. Data collection and analysis: Primary outcomes were severity of aortic valve stenosis (evaluated by echocardiographic criteria: mean pressure gradient, valve area and aortic jet velocity, freedom from valve replacement and death from cardiovascular cause. Secondary outcomes were hospitalization for any reason, overall mortality, adverse events and patient quality of life. Two review authors independently selected trials for inclusion, extracted data and assessed the risk of bias. The GRADE methodology was employed to assess the quality of result findings and the GRADE profiler (GRADEPRO was used to import data from Review Manager 5.3 to create a 'Summary of findings' table. MAIN RESULTS: We included four RCTs with 2360 participants comparing statins (1185 participants with placebo (1175 participants. We found low-quality evidence for our primary outcome of severity of aortic valve stenosis, evaluated by mean pressure gradient (mean difference (MD -0.54, 95% confidence interval (CI -1.88 to 0.80; participants = 1935; studies = 2, valve area (MD -0.07, 95% CI -0.28 to 0.14; participants = 127; studies = 2

  10. Lowering plasma cholesterol levels halts progression of aortic valve disease in mice

    Science.gov (United States)

    Miller, Jordan D.; Weiss, Robert M.; Serrano, Kristine M.; Brooks, Robert M.; Berry, Christopher J.; Zimmerman, Kathy; Young, Stephen G.; Heistad, Donald D.

    2009-01-01

    Background Treatment of hyperlipidemia produces functional and structural improvements in atherosclerotic vessels. However, the effects of treating hyperlipidemia on the structure and function of the aortic valve has been controversial, and any effects could be confounded by pleiotropic effects of hypolipidemic treatment. The goal of this study was to determine whether reducing elevated plasma lipid levels with a “genetic switch” in Reversa mice (Ldlr−/−/Apob100/100/Mttpfl/fl/Mx1Cre+/+) reduces oxidative stress, reduces proosteogenic signaling, and retards the progression of aortic valve disease. Methods and Results After 6 months of hypercholesterolemia, Reversa mice exhibited increases in superoxide, lipid deposition, myofibroblast activation, calcium deposition, and pro-osteogenic protein expression in the aortic valve. Maximum aortic valve cusp separation, as judged by echocardiography, was not altered. During an additional 6 months of hypercholesterolemia, superoxide levels, valvular lipid deposition, and myofibroblast activation remained elevated. Furthermore, calcium deposition and pro-osteogenic gene expression became more pronounced and the aortic cusp separation decreased from 0.85 ± 0.04 to 0.70 ± 0.04 mm (mean ± SE; p < 0.05). Rapid normalization of cholesterol levels at 6 months of age (by inducing expression of Cre recombinase) normalized aortic valve superoxide levels, decreased myofibroblast activation, reduced valvular calcium burden, suppressed pro-osteogenic signaling cascades, and prevented the reductions in aortic valve cusp separation. Conclusions Collectively, these data indicate that reducing plasma lipid levels by genetic inactivation of the mttp gene in hypercholesterolemic mice with early aortic valve disease normalizes oxidative stress, reduces pro-osteogenic signaling, and halts the progression of aortic valve stenosis. PMID:19433756

  11. Myocardial infarction with aortic banding. A combined rat model of heart failure.

    Science.gov (United States)

    Anthonio, R L; van Veldhuisen, D J; Scholtens, E; van Bekkum, C; de Boer, E; van Gilst, W H

    1997-09-01

    The effect of additional abdominal aortic banding on parameters of heart failure was studied in male Wistar rats with myocardial infarction. Contractile function was studied 8-9 weeks after operation, with an isoprenaline dose response protocol, in a retrograde Langendorff perfusion. Also, plasma noradrenaline concentration, infarct size and morphology were determined. Compared with controls, myocardial infarction/aortic banding animals showed a decreased contractile function, both at baseline and after maximal isoprenaline stimulation, and elevated noradrenaline levels (1316 +/- 94) vs 1909 +/- 174 pg/ml, both p Emax was significantly decreased. In aortic banding rats, contractile parameters were not significantly impaired, compared with controls. Both myocardial infarction and the myocardial infarction/aortic banding animals, but not aortic banding rats, had a significantly increased heart weight (1.4 +/- 0.04 g for controls vs 1.7 +/- 0.08 g for myocardial infarction and 2.0 +/- 0.12 g for myocardial infarction/aortic banding), and left ventricular cavity volume (19 +/- 1.4 mm3 for controls vs 49 +/- 5.5 mm3 for myocardial infarction and 48 +/- 4.3 mm3 for myocardial infarction/aortic banding) compared to control animals. Infarct size was 36.0% and 39.4% for the myocardial infarction and myocardial infarction/aortic banding animals, respectively. We conclude that myocardial infarction/aortic banding provides a new experimental model, which may yield important information and pathophysiology which allow evaluation of changes that may mimic clinical myocardial infarction with concomitant hypertension.

  12. Decreased expression of fibulin-4 in aortic wall of aortic dissection.

    Science.gov (United States)

    Huawei, P; Qian, C; Chuan, T; Lei, L; Laing, W; Wenlong, X; Wenzhi, L

    2014-02-01

    In this research, we will examine the expression of Fibulin-4 in aortic wall to find out its role in aortic dissection development. The samples of aortic wall were obtained from 10 patients operated for acute ascending aortic dissection and five patients for chronic ascending aortic dissection. Another 15 pieces of samples from patients who had coronary artery bypass were as controls. The aortic samples were stained with aldehyde magenta dyeing to evaluate the arrangement of elastic fibers. The Fibulin-4 protein and mRNA expression were both determined by Western blot and realtime quantitative polymerase chain reaction. Compared with the control group, both in acute and chronic ascending aortic dissection, elastic fiber fragments increased and the expression of fibulin-4 protein significantly decreased (P= 0.045 < 0.05). The level of fibulin-4 mRNA decreased in acute ascending aortic dissection (P= 0.034 < 0.05), while it increased in chronic ascending aortic dissection (P=0.004 < 0.05). The increased amounts of elastic fiber fragments were negatively correlated with the expression of fibulin-4 mRNA in acute ascending aortic dissection. In conclusion, in aortic wall of ascending aortic dissection, the expression of fibulin-4 protein decreased and the expression of fibulin-4 mRNA was abnormal. Fibulin-4 may play an important role in the pathogenesis of aortic dissection.

  13. Svensson Class IV Ascending Aortic Dissection, Often Confused With Penetrating Ulcer

    Directory of Open Access Journals (Sweden)

    Mitsomoy Michel Francklyn

    2015-03-01

    Full Text Available We present the case of a 64 years old male patient who had recently suffered an infective aortic valve endocarditis (Streptococcus agalactiae complicated by embolic arthritis of the right hip. Initial echocardiography revealed moderate aortic insufficiency developed on a tricuspidaortic valve with a small vegetation (5 mm × 4 mm on the left coronary cusp. Furthermore, ananeurysmal dilatation of the ascending aorta (maximal diameter, 54 mm was noted. Other heartvalves and left ventricular function were considered normal. The patient completed a 4 weekscourse of antibiotherapy, and the right hip arthritis was treated by drainage and synovectomy.The patient was subsequently referred to surgery on an outpatient basis for the aneurysm of theascending aorta. Preoperative computed tomography showed localized aortic dissection of thetubular ascending aorta characterized by an intimal tear without medial hematoma but excentricbulging of the aortic wall. This lesion was initially considered a penetrating ulcer of the aortic wallThe operative specimen allowed to make differential diagnosis with a penetrating aortic ulcer byshowing that the lesion did not develop within an atherosclerotic plaque. However, downstreamextension of the dissection was probably limited by the presence of transmural calcifications on itsdistal side. The patient underwent successful complete aortic root replacement using a stentlessFreestyle bioprosthesis with Dacron graft extension as reported previously

  14. Growth hormone receptor deficiency in mice results in reduced systolic blood pressure and plasma renin, increased aortic eNOS expression, and altered cardiovascular structure and function

    DEFF Research Database (Denmark)

    Egecioglu, E; Andersson, I J; Bollano, E;

    2007-01-01

    To study the role of the growth hormone receptor (GHR) in the development of cardiovascular structure and function, female GHR gene-disrupted or knockout (KO) and wild-type (WT) mice at age 18 wk were used. GHR KO mice had lower plasma renin levels (12 +/- 2 vs. 20 +/- 4 mGU/ml, P ....05) in GHR KO. Relative left ventricular weight was 14% lower in GHR KO mice (P ... thickness was decreased in GHR KO (P KO mice, whereas the aorta of GHR KO mice showed an increased sensitivity...

  15. Transcatheter aortic valve implantation versus surgical aortic valve replacement for severe aortic stenosis: a meta analysis

    Institute of Scientific and Technical Information of China (English)

    WU Yi-cheng; ZHANG Jian-feng; SHEN Wei-feng; ZHAO Qiang

    2013-01-01

    Background Transcatheter aortic valve implantation (TAVI) has emerged as the treatment choice for non-operable patients with severe symptomatic aortic stenosis (AS) and may be a good alternative to surgery for those at very high or prohibitive surgical risk.We performed a meta-analysis to evaluate the comparative benefits of TAVI versus surgical aortic valve replacement (SAVR) in patients with severe AS.Methods A comprehensive literature search of PubMed,Embase,ScienceDirect and Cochrane Central Register of Controlled trials was performed,and randomized trials as well as cohort studies with propensity score analysis were included.Results One randomized trial (n=699) and six retrospective cohort studies (n=781) were selected for meta-analysis.Mortality at 30-day and 1-year follow-up was comparable between TAVI and SAVR.Despite similar incidences of stroke,myocardial infarction,re-operation for bleeding,and renal failure requiring dialysis,TAVI was associated with a lower occurrence rate of new-onset atrial fibrillation (OR 0.51,95% CI 0.33-0.78) and shorter procedural time (mean difference -67.50 minutes,95% CI-87.20 to-47.81 minutes).Post-operative aortic regurgitation and permanent pacemaker implantation were more common in patients after TAVI than in those with SAVR (OR 5.53,95% CI 3.41-8.97; OR 1.71,95% Cl 1.02-2.84,respectively).Conclusion In patients with severe symptomatic AS,TAVI and SAVR did not differ with respect to short-and mid-term survival,but the incidence of permanent pacemaker implantation and post-procedural aortic regurgitation remain relatively high after TAVI.

  16. Bicuspid aortic valve hemodynamics: a fluid-structure interaction study

    Science.gov (United States)

    Chandra, Santanu; Seaman, Clara; Sucosky, Philippe

    2011-11-01

    The bicuspid aortic valve (BAV) is a congenital defect in which the aortic valve forms with two leaflets instead of three. While calcific aortic valve disease (CAVD) also develops in the normal tricuspid aortic valve (TAV), its progression in the BAV is more rapid. Although studies have suggested a mechano-potential root for the disease, the native BAV hemodynamics remains largely unknown. This study aimed at characterizing BAV hemodynamics and quantifying the degree of wall-shear stress (WSS) abnormality on BAV leaflets. Fluid-structure interaction models validated with particle-image velocimetry were designed to predict the flow and leaflet dynamics in idealized TAV and BAV anatomies. Valvular function was quantified in terms of the effective orifice area. The regional leaflet WSS was characterized in terms of oscillatory shear index, temporal shear magnitude and temporal shear gradient. The predictions indicate the intrinsic degree of stenosis of the BAV anatomy, reveal drastic differences in shear stress magnitude and pulsatility on BAV and TAV leaflets and confirm the side- and site-specificity of the leaflet WSS. Given the ability of abnormal fluid shear stress to trigger valvular inflammation, these results support the existence of a mechano-etiology of CAVD in the BAV.

  17. Efectos del ejercicio isométrico sobre la función diastólica en pacientes con estenosis aortica severa Effect of isometric exercise on diastolic function in patients with severe aortic stenosis

    Directory of Open Access Journals (Sweden)

    M. Donato

    2003-01-01

    Full Text Available El objetivo del estudio fue determinar los efectos del ejercicio isométrico sobre la función diastólica, en pacientes con estenosis aórtica sin lesión coronaria (grupo 1, G2, n= 9 y con lesión coronaria (grupo 2, G2, n=11. Pacientes sometidos a un cateterismo cardíaco realizaron ejercicio isométrico hasta que la frecuencia cardíaca se incrementó un 32±9%, con respecto a su valor basal. Se midieron la presión sistólica ventricular izquierda (PSVI y la presión de fin de diástole (PDFVI y se calculó la constante de tiempo de caída de la presión ventricular (tau, t, y la máxima velocidad de ascenso de la presión (+dP/dt máx. La +dP/dt máx aumentó en G1 y G2, durante el ejercicio, desde un valor de 1989±190 y 2428±220 mmHg/seg, hasta un valor de 2286±214 y 2661±230 mmHg/seg, respectivamente; retornando luego a su valor basal. La PDFVI aumentó, durante el ejercicio, en G1 y G2 desde un valor de 30.1±2.7 y 26.5±2.2 mmHg hasta 38.4±1.7 y 36.1±4.0 mmHg, respectivamente (pThe objective of the study was to determine the effects of isometric exercise on the diastolic function in patients with aortic stenosis without coronary lesion (group 1, G1, n = 9 and with coronary lesion (group 2, G2, n=11. Patients subjected to a cardiac catheterization performed isometric exercise until their heart rate increased in 32±9 % compared to baseline. The left ventricular systolic pressure, the +dP/dt max, and the end diastolic pressure (LVEDP were measured, and the time constant of pressure decay (tau, t was calculated. The +dP/dt max increased in G1 and G2 during exercise, from a value of 1989±190 and 2428±220 mmHg/sec up to 2286±214 y 2661±230 mmHg/sec, respectively, returning afterwards to its baseline value. The LVEDP increased during exercise in G1 and G2 from a value of 30.1±2.7 and 26.5±2.2 mmHg up to 38.4±1.7 and 36.1±4.0 mmHg, respectively (p<0.05, returning to its baseline value only in G1. The tau (t increased during

  18. [Surgical technique of aortic valve replacement for small aortic annulus in elderly patients].

    Science.gov (United States)

    Hata, T; Fujiwara, K; Furukawa, H; Tsushima, Y; Yoshitaka, H; Kuinose, M; Minami, H; Ishida, A; Tamura, K; Totsugawa, T; Kanemitsu, H; Ozawa, M

    2006-04-01

    Recent reports have shown that aortic valve replacement in elderly patients over 65 years with atherosclerotic aortic stenosis and a small aortic annulus is possible by using a small sized bioprosthesis (Carpentier-Edwards pericardial valve). Here we present out surgical technique. Firstly, the native calcified aortic valve was removed completely to gain total exposure of the surrounding aortic root and sinus of Valsalva like Bentall procedure. Secondly, a small sized bioprosthesis was implanted with intermittent noneverting mattress 2-0 sutures with spaghetti and small polytetrafluoroethylene (PTFE) felt. Aortic annulus is the dilated by inserting Hegar dilator sizing from 25 to 27 mm. Therefore, aortic valve replacement for small aortic annulus in intra- or supra-annular position should be easily accomplished. Good surgical results and hemodynamic state were achieved in 25 consecutive cases using this technique.

  19. Early severe coronary artery disease and aortic coarctation in a child with familial hypercholesterolaemia.

    Science.gov (United States)

    Labib, Dina; Soliman, Haytham; Said, Kareem; Sorour, Khaled

    2016-11-30

    An 11-year-old boy presented with easy fatigability, multiple xanthomas, and absent pedal pulsations. Laboratory workup showed severe hypercholesterolaemia and non-invasive imaging revealed 'normally functioning' bicuspid aortic valve and tight aortic coarctation. Coronary angiography showed severe right coronary artery (RCA) stenosis. Medical treatment resulted in significant improvement of dyslipidaemia. We successfully performed balloon dilation and stenting of his coarctation, as well as percutaneous coronary intervention for RCA lesion.

  20. In vivo transfection of manganese superoxide dismutase gene or nuclear factor κB shRNA in nodose ganglia improves aortic baroreceptor function in heart failure rats.

    Science.gov (United States)

    Zhang, Dongze; Liu, Jinxu; Tu, Huiyin; Muelleman, Robert L; Cornish, Kurtis G; Li, Yu-Long

    2014-01-01

    Arterial baroreflex sensitivity is attenuated in chronic heart failure (CHF) state, which is associated with cardiac arrhythmias and sudden cardiac death in patients with CHF. Our previous study showed that CHF-induced sodium channel dysfunction in the baroreceptor neurons was involved in the blunted baroreflex sensitivity in CHF rats. Mitochondria-derived superoxide overproduction decreased expression and activation of the sodium channels in the baroreceptor neurons from CHF rats. However, the molecular mechanisms responsible for the sodium channel dysfunction in the baroreceptor neurons from CHF rats remain unknown. We tested the involvement of nuclear factor κB (NFκB) in the sodium channel dysfunction and evaluated the effects of in vivo transfection of manganese superoxide dismutase gene and NFκB shRNA on the baroreflex function in CHF rats. CHF was developed at 6 to 8 weeks after left coronary artery ligation in adult rats. Western blot and chromatin immunoprecipitation data showed that phosphorylated NFκB p65 and ability of NFκB p65 binding to the sodium channel promoter were increased in the nodose ganglia from CHF rats. In vivo transfection of adenoviral manganese superoxide dismutase gene or lentiviral NFκB p65 shRNA into the nodose ganglia partially reversed CHF-reduced sodium channel expression and cell excitability in the baroreceptor neurons and improved CHF-blunted arterial baroreflex sensitivity. Additionally, transfection of adenoviral manganese superoxide dismutase also inhibited the augmentation of phosphorylated NFκB p65 in the nodose neurons from CHF rats. The present study suggests that superoxide-NFκB signaling contributes to CHF-induced baroreceptor dysfunction and resultant impairment of baroreflex function.

  1. Aortic endograft sizing in trauma patients with hemodynamic instability

    NARCIS (Netherlands)

    Jonker, Frederik H. W.; Verhagen, Hence J. M.; Mojibian, Hamid; Davis, Kimberly A.; Moll, Frans L.; Muhs, Bart E.

    2010-01-01

    Objectives: To investigate changes in aortic diameter in hemodynamically unstable trauma patients and the implications for sizing of thoracic endovascular aortic repair (TEVAR) in patients with traumatic thoracic aortic injury (TTAI). Methods: We retrospectively evaluated all trauma patients that we

  2. Indexing aortic valve area by body surface area increases the prevalence of severe aortic stenosis

    DEFF Research Database (Denmark)

    Jander, Nikolaus; Gohlke-Bärwolf, Christa; Bahlmann, Edda

    2014-01-01

    To account for differences in body size in patients with aortic stenosis, aortic valve area (AVA) is divided by body surface area (BSA) to calculate indexed AVA (AVAindex). Cut-off values for severe stenosis are......To account for differences in body size in patients with aortic stenosis, aortic valve area (AVA) is divided by body surface area (BSA) to calculate indexed AVA (AVAindex). Cut-off values for severe stenosis are...

  3. Characterization of human aortic elastase found in patients with abdominal aortic aneurysms.

    Science.gov (United States)

    Cohen, J R; Mandell, C; Wise, L

    1987-10-01

    Recent evidence indicates that the homeostatic balance between elastase and antiprotease activity is altered in the infrarenal aorta of those patients with different types of aortic pathologic findings. The specific properties of elastase found in the aorta of patients with abdominal aortic aneurysms (AAA) are discussed herein. Activity of elastase extracted from ten pooled AAA specimens was observed when incubated with several inhibitors: 13.2 per cent for phenyl-suphonyl flouride (PSF); 43.3 per cent for ethylenediaminetetraacetic acid (EDTA); 77.7 per cent for pepstatin; 137.0 per cent for leupeptin, and 24.0 per cent for alpha-1-antitrypsin. Irreversible inhibition by PSF indicates that the elastase is a serine protease. The elastase is most likely not a metallo enzyme, since it had no absolute requirement for divalent cations as indicated by only partial inhibition by EDTA. Elastase activity is most likely not due to cathepsins B or D, since cathepsins are active in an acid pH and selectively inhibited by leupeptin and pepstatin. The pH curve revealed a maximum activity at pH 8.2 and elastase activity was significantly inhibited by alpha-1-antitrypsin in a dose response manner determining functional elastase activity. These data indicate that the elastase in the aorta of patients with an AAA has the exact properties of the serine elastase found in the smooth muscle cells of the aorta in rats. These results also confirm the critical role of alpha-1-antitrypsin in determining functional elastase activity. Smooth muscle cell regulation of elastin metabolism may be important in determining why some patients have AAA and others have occlusive aortic disease develop.

  4. The hemodynamic effects of acute aortic regurgitation into a stiffened left ventricle resulting from chronic aortic stenosis.

    Science.gov (United States)

    Okafor, Ikechukwu; Raghav, Vrishank; Midha, Prem; Kumar, Gautam; Yoganathan, Ajit

    2016-06-01

    Acute aortic regurgitation (AR) post-chronic aortic stenosis is a prevalent phenomenon occurring in patients who undergo transcatheter aortic valve replacement (TAVR) surgery. The objective of this work was to characterize the effects of left ventricular diastolic stiffness (LVDS) and AR severity on LV performance. Three LVDS models were inserted into a physiological left heart simulator. AR severity was parametrically varied through four levels (ranging from trace to moderate) and compared with a competent aortic valve. Hemodynamic metrics such as average diastolic pressures (DP) and reduction in transmitral flow were measured. AR index was calculated as a function of AR severity and LVDS, and the work required to make up for lost volume due to AR was estimated. In the presence of trace AR, higher LVDS had up to a threefold reduction in transmitral flow (13% compared with 3.5%) and a significant increase in DP (2-fold). The AR index ranged from ∼42 to 16 (no AR to moderate AR), with stiffer LVs having lower values. To compensate for lost volume due to AR, the low, medium, and high LVDS models were found to require 5.1, 5.5, and 6.6 times more work, respectively. This work shows that the LVDS has a significant effect on the LV performance in the presence of AR. Therefore, the LVDS of potential TAVR patients should be assessed to gain an initial indication of their ability to tolerate post-procedural AR.

  5. Transcatheter aortic valve replacement for bicuspid aortic stenosis 13years post heart transplant.

    Science.gov (United States)

    Julien, Maureen B; Desai, Nimesh; Brozena, Susan; Herrmann, Howard C

    2016-12-16

    Despite the widespread use of transcatheter aortic valve replacement (TAVR) for moderate and high-risk patients with severe aortic stenosis, it is utilized less frequently in patients with bicuspid aortic valves (BAV). Orthotopic heart transplant (OHT) donors tend to be younger and may have undiagnosed BAV. We present a case of successful TAVR in a patient with BAV thirteen years after OHT.

  6. Transcatheter valve-in-valve implantation due to severe aortic regurgitation in a degenerated aortic homograft

    DEFF Research Database (Denmark)

    Olsen, Lene Kjaer; Engstrøm, Thomas; Søndergaard, Lars

    2009-01-01

    a successful valve-in-valve implantation of a CoreValve aortic valve prosthesis through the right subclavian artery in a case of severe aortic regurgitation within a degenerated aortic homograft. The case exemplifies the possibilities of expanding the indications for TAVI, as well as other vascular access...

  7. New-onset atrial fibrillation after surgical aortic valve replacement and transcatheter aortic valve implantation

    DEFF Research Database (Denmark)

    Jørgensen, Troels Højsgaard; Thygesen, Julie Bjerre; Thyregod, Hans Gustav;

    2015-01-01

    Surgical aortic valve replacement (SAVR) and, more recently, transcatheter aortic valve implantation (TAVI) have been shown to be the only treatments that can improve the natural cause of severe aortic valve stenosis. However, after SAVR and TAVI, the incidence of new-onset atrial fibrillation...

  8. New-Onset Atrial Fibrillation After Surgical Aortic Valve Replacement and Transcatheter Aortic Valve Implantation

    DEFF Research Database (Denmark)

    Jørgensen, Troels Højsgaard; Thygesen, Julie Bjerre; Thyregod, Hans Gustav;

    2015-01-01

    Surgical aortic valve replacement (SAVR) and, more recently, transcatheter aortic valve implantation (TAVI) have been shown to be the only treatments that can improve the natural cause of severe aortic valve stenosis. However, after SAVR and TAVI, the incidence of new-onset atrial fibrillation...

  9. Aortic valvuloplasty of calcific aortic stenosis with monofoil and trefoil balloon catheters: practical considerations

    NARCIS (Netherlands)

    S. Plante (Sylvain); M.J.B.M. van den Brand (Marcel); L.C.P. van Veen; C. di Mario (Carlo); C.E. Essed; K.J. Beatt (Kevin); P.W.J.C. Serruys (Patrick)

    1990-01-01

    textabstractIn order to evaluate the relation between balloon design (monofoil, trefoil) and valvular configuration, experimental aortic valvuloplasty was performed in four post-mortem hearts with calcific aortic stenosis of various morphology. The degree of obstruction of the aortic orifice was ass

  10. The Efficacy of Autologous Femoropopliteal Vein Reconstruction for Primary Aortic and Aortic Graft Infection

    NARCIS (Netherlands)

    Dirven, M.; Jagt, M.F.P. van der; Barendregt, W.B.; Vliet, D. van der

    2015-01-01

    BACKGROUND: The objective of our study was to analyze the efficacy of autologous superficial femoropopliteal vein reconstruction for primary aortic or aortic graft infection. METHODS: We performed a retrospective analysis of 14 patients treated for an infected aortic prosthesis or primary infected a

  11. Low-gradient aortic stenosis.

    Science.gov (United States)

    Clavel, Marie-Annick; Magne, Julien; Pibarot, Philippe

    2016-09-07

    An important proportion of patients with aortic stenosis (AS) have a 'low-gradient' AS, i.e. a small aortic valve area (AVA <1.0 cm(2)) consistent with severe AS but a low mean transvalvular gradient (<40 mmHg) consistent with non-severe AS. The management of this subset of patients is particularly challenging because the AVA-gradient discrepancy raises uncertainty about the actual stenosis severity and thus about the indication for aortic valve replacement (AVR) if the patient has symptoms and/or left ventricular (LV) systolic dysfunction. The most frequent cause of low-gradient (LG) AS is the presence of a low LV outflow state, which may occur with reduced left ventricular ejection fraction (LVEF), i.e. classical low-flow, low-gradient (LF-LG), or preserved LVEF, i.e. paradoxical LF-LG. Furthermore, a substantial proportion of patients with AS may have a normal-flow, low-gradient (NF-LG) AS: i.e. a small AVA-low-gradient combination but with a normal flow. One of the most important clinical challenges in these three categories of patients with LG AS (classical LF-LG, paradoxical LF-LG, and NF-LG) is to differentiate a true-severe AS that generally benefits from AVR vs. a pseudo-severe AS that should be managed conservatively. A low-dose dobutamine stress echocardiography may be used for this purpose in patients with classical LF-LG AS, whereas aortic valve calcium scoring by multi-detector computed tomography is the preferred modality in those with paradoxical LF-LG or NF-LG AS. Although patients with LF-LG severe AS have worse outcomes than those with high-gradient AS following AVR, they nonetheless display an important survival benefit with this intervention. Some studies suggest that transcatheter AVR may be superior to surgical AVR in patients with LF-LG AS.

  12. Reference Values for Cardiac and Aortic Magnetic Resonance Imaging in Healthy, Young Caucasian Adults

    Science.gov (United States)

    Eikendal, Anouk L. M.; Bots, Michiel L.; Haaring, Cees; Saam, Tobias; van der Geest, Rob J.; Westenberg, Jos J. M.; den Ruijter, Hester M.; Hoefer, Imo E.; Leiner, Tim

    2016-01-01

    Background Reference values for morphological and functional parameters of the cardiovascular system in early life are relevant since they may help to identify young adults who fall outside the physiological range of arterial and cardiac ageing. This study provides age and sex specific reference values for aortic wall characteristics, cardiac function parameters and aortic pulse wave velocity (PWV) in a population-based sample of healthy, young adults using magnetic resonance (MR) imaging. Materials and Methods In 131 randomly selected healthy, young adults aged between 25 and 35 years (mean age 31.8 years, 63 men) of the general-population based Atherosclerosis-Monitoring-and-Biomarker-measurements-In-The-YOuNg (AMBITYON) study, descending thoracic aortic dimensions and wall thickness, thoracic aortic PWV and cardiac function parameters were measured using a 3.0T MR-system. Age and sex specific reference values were generated using dedicated software. Differences in reference values between two age groups (25–30 and 30–35 years) and both sexes were tested. Results Aortic diameters and areas were higher in the older age group (all p<0.007). Moreover, aortic dimensions, left ventricular mass, left and right ventricular volumes and cardiac output were lower in women than in men (all p<0.001). For mean and maximum aortic wall thickness, left and right ejection fraction and aortic PWV we did not observe a significant age or sex effect. Conclusion This study provides age and sex specific reference values for cardiovascular MR parameters in healthy, young Caucasian adults. These may aid in MR guided pre-clinical identification of young adults who fall outside the physiological range of arterial and cardiac ageing. PMID:27732640

  13. Aortic dilatation in children with systemic hypertension.

    Science.gov (United States)

    Gupta-Malhotra, Monesha; Devereux, Richard B; Dave, Archana; Bell, Cynthia; Portman, Ronald; Milewicz, Diana

    2014-04-01

    The aim of the study was to determine the presence of aortic dilatation in hypertensive children, the prevalence of which is 4% to 10% in hypertensive adults. Prospectively enrolled multiethnic children, untreated for their hypertension, underwent an echocardiogram to exclude congenital heart disease and evaluate for end-organ damage and aortic size. The aorta was measured in the parasternal long-axis view at three levels: the sinus of Valsalva, supra-tubular junction, and the ascending aorta. Aortic dilatation was determined by z-score >2 at any one of the levels measured. Hypertension was defined as blood pressure above the 95th percentile based on the Fourth Working Group criteria confirmed by 24-hour ambulatory blood pressure monitoring. Among 142 consecutive hypertensive children (median age, 14 years; 45% females) aortic dilatation was detected in 2.8% (95% confidence interval, 1%-7%; median age, 16 years; 100% females). Children with aortic dilatation, when compared with those without, had significantly more aortic valve insufficiency (P = .005) and left ventricular hypertrophy (P = .018). Prevalence of aortic dilatation was 2.8% and was associated with significantly more aortic insufficiency and left ventricular hypertrophy in comparison to those without aortic dilatation.

  14. Hybrid treatment of penetrating aortic ulcer

    Energy Technology Data Exchange (ETDEWEB)

    Lara, Juan Antonio Herrero; Martins-Romeo, Daniela de Araujo; Escudero, Carlos Caparros; Falcon, Maria del Carmen Prieto; Batista, Vinicius Bianchi, E-mail: jaherrero5@hotmail.com [Unidade de Gestao Clinica (UGC) de Diagnostico por Imagem - Hosppital Universitario Virgen Macarena, Sevilha (Spain); Vazquez, Rosa Maria Lepe [Unit of Radiodiagnosis - Hospital Nuestra Senora de la Merced, Osuna, Sevilha (Spain)

    2015-05-15

    Penetrating atherosclerotic aortic ulcer is a rare entity with poor prognosis in the setting of acute aortic syndrome. In the literature, cases like the present one, located in the aortic arch, starting with chest pain and evolving with dysphonia, are even rarer. The present report emphasizes the role played by computed tomography in the diagnosis of penetrating atherosclerotic ulcer as well as in the differentiation of this condition from other acute aortic syndromes. Additionally, the authors describe a new therapeutic approach represented by a hybrid endovascular surgical procedure for treatment of the disease. (author)

  15. Aortic dissection: magnetic resonance imaging.

    Science.gov (United States)

    Amparo, E G; Higgins, C B; Hricak, H; Sollitto, R

    1985-05-01

    Fifteen patients with suspected or known aortic dissection were imaged with magnetic resonance (MR). Thirteen of these patients were eventually shown to have dissection. In most instances the diagnosis was established by aortography and/or computed tomography (CT) prior to the MR study. Surgical proof (6/13) and/or aortographic proof (10/13) were available in 11/13 patients with aortic dissection. MR demonstrated the intimal flap and determined whether the dissection was type A or type B. In addition, MR: differentiated between the true and false lumens; determined the origins of the celiac, superior mesenteric, and renal arteries from the true or false lumen in the cases where the dissection extended into the abdominal aorta (8/12); allowed post-surgical surveillance of the dissection; and identified aortoannular ectasia in the three patients who had Marfan syndrome. In addition to the 13 cases with dissection, there were two cases in whom the diagnosis of dissection was excluded by MR. Our early experience suggests that MR can serve as the initial imaging test in clinically suspected cases of aortic dissection and that the information provided by MR is sufficient to manage many cases. Additionally, MR obviates the use of iodinated contrast media.

  16. A prospective, randomised trial of transapical transcatheter aortic valve implantation vs. surgical aortic valve replacement in operable elderly patients with aortic stenosis

    DEFF Research Database (Denmark)

    Nielsen, Hans Henrik Møller; Klaaborg, Kaj E; Nissen, Henrik

    2012-01-01

    In a prospective randomised trial we aimed to compare transapical transcatheter aortic valve implantation (a-TAVI) with surgical aortic valve replacement (SAVR) in operable elderly patients.......In a prospective randomised trial we aimed to compare transapical transcatheter aortic valve implantation (a-TAVI) with surgical aortic valve replacement (SAVR) in operable elderly patients....

  17. Burro aortic collagen: composition and characteristics of interaction with platelets

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, M.D. (Comparative Animal Research Lab., Oak Ridge, TN); Huang, W.O.W.; Cross, F.H.; Lin, K.T.D.

    1979-03-01

    A collagenous protein(s) from the aortas of three aged burros (Equus asinus) was isolated, using an acid (83.5 mM glacial acetic acid) extraction technique and subsequent pepsin digestion of the extracts with extensive dialysis. This protein(s) was then precipitated by adding solid NaCl (w/v, 9.45 g/100 ml) to the dialyzed aortic tissue extracts. The precipitate was collected by ultracentrifugation, concentrated by dissolving in one-fourth the original volume of acetic acid, and again extensively dialyzed. Values for amino acids in residues/1,000 indicated that the extractable aortic material(s) contained substantial amounts of proline, hydroxyproline, lysine, hydroxylysine, cysteine, and all other amino acid residues usually found in collagen. Examination by electrophoresis in sodium dodecyl sulfate polyacrylamide-gel indicated the presence of 5 major polypeptide subunits of the molecular weight range of 116,000 to 300,000. A powerful inducer of platelet aggregation was found in the acid solubilized, pepsin-digested aortic extracts. Human platelets were sensitive to the agent(s) down to 0.1 to 0.2 ..mu..g of aortic solids added to 0.45 ml of platelet-rich plasma. Platelets from goats and sheep were sensitive down to additions of 0.2 ..mu..g of solids, burro platelets to 0.5 to 1 ..mu..g, bovine platelets to 1 to 2 ..mu..g, and swine platelets to 2 to 3 ..mu..g. Thus, this powerful burro aortic collagen-containing material(s) may help to distinguish minor modifications in functional characteristics of platelets from persons or animals suffering from hemostatic or thrombotic disorders.

  18. Submillisecond precision of the input-output transformation function mediated by fast sodium dendritic spikes in basal dendrites of CA1 pyramidal neurons.

    Science.gov (United States)

    Ariav, Gal; Polsky, Alon; Schiller, Jackie

    2003-08-27

    The ability of cortical neurons to perform temporally accurate computations has been shown to be important for encoding of information in the cortex; however, cortical neurons are expected to be imprecise temporal encoders because of the stochastic nature of synaptic transmission and ion channel gating, dendritic filtering, and background synaptic noise. Here we show for the first time that fast local spikes in basal dendrites can serve to improve the temporal precision of neuronal output. Integration of coactivated, spatially distributed synaptic inputs produces temporally imprecise output action potentials within a time window of several milliseconds. In contrast, integration of closely spaced basal inputs initiates local dendritic spikes that amplify and sharpen the summed somatic potential. In turn, these fast basal spikes allow precise timing of output action potentials with submillisecond temporal jitter over a wide range of activation intensities and background synaptic noise. Our findings indicate that fast spikes initiated in individual basal dendrites can serve as precise "timers" of output action potentials in various network activity states and thus may contribute to temporal coding in the cortex.

  19. ACE inhibition attenuates uremia-induced aortic valve thickening in a novel mouse model

    DEFF Research Database (Denmark)

    Simolin, Mikko A; Pedersen, Tanja X; Bro, Susanne;

    2009-01-01

    BACKGROUND: We examined whether impaired renal function causes thickening of the aortic valve leaflets in hyperlipidemic apoE-knockout (apoE-/-) mice, and whether the putative effect on the aortic valves could be prevented by inhibiting the angiotensin-converting enzyme (ACE) with enalapril....... METHODS: Thickening of the aortic valve leaflets in apoE-/- mice was induced by producing mild or moderate chronic renal failure resulting from unilateral nephrectomy (1/2 NX, n = 18) or subtotal nephrectomy (5/6 NX, n = 22), respectively. Additionally, the 5/6 NX mice were randomized to no treatment (n...... treated with enalapril had significantly thinner leaflets than did the untreated 5/6 NX mice (P = 0.014). CONCLUSION: Moderate uremia causes thickening of the aortic valves in apoE-/- mice, which can be attenuated by ACE inhibition. The nephrectomized apoE-/- mouse constitutes a new model...

  20. Repair of recurrent pseudoaneurysm of the mitral-aortic intervalvular fibrosa: Role of transesophageal echocardiography

    Directory of Open Access Journals (Sweden)

    Shreedhar S Joshi

    2014-01-01

    Full Text Available Pseudoaneurysm of mitral-aortic intervalvular fibrosa (P-MAIVF is a rare cardiac surgical condition. P-MAIVF commonly occurs as a complication of aortic and mitral valve replacement surgeries. The surgical trauma during replacement of the valves weakens the avascular mitral and aortic intervalvular area. We present a case of P-MAIVF recurrence 5 years after a primary repair. Congestive cardiac failure was the presenting feature with mitral and aortic regurgitation. In view of the recurrence, the surgical team planned for a double valve replacement. The sewing rings of the two prosthetic-valves were interposed to close the mouth of the pseudoaneurysm and to provide mechanical reinforcement of the MAIVF. Intra-operative transesophageal echocardiography (TEE helped in delineating the anatomy, extent of the lesion, rupture of one of the pseudoaneurysm into left atrium and severity of the valvular regurgitation. Post-procedure TEE confirmed complete obliteration of the pseudoaneurysm and prosthetic valve function.

  1. Effect of pulmonary autograft transplantation in the surgical treatment of aortic valve disease

    Institute of Scientific and Technical Information of China (English)

    LI Wen-bin; LIU Hai-yan; ZHOU Qi-wen; XU Xiu-fang; ZHANG Jian-qun; SONG Shi-qiu; PENG Jin-feng; WANG Sheng-xun; LIU Wei; ZHOU Hai-po; WANG Zhu-heng

    2008-01-01

    Background Aortic root replacement with pulmonary autograft (Ross procedure) has the advantages of good haemodynamics and growth potential without the need for anticoagulation.In this study,we reviewed our expedence of the Ross procedure for patients with aortic valve disease.Methods From October 1994 to January 2005,42 Ross procedures were performed in our centre.There were 30 males and 12 females.The mean age was 28+15 years (range,5-56 years).Congenital heart disease (CHD) with aortic valve stenosis (AS) and/or aortic valve insufficiency (A1) in 40 cases including one associated with ventdcular septal defect (VSD),degenerated aortic valve disease with AS in 1 and subacutive bacterial endocarditis (SBE) with A1 in 1 were studied.The diagnosis was made by ultracardiography (UCG) in all patients.The mean aortic valve annulus diameter (AVD) was (2.45±0.31) cm and pulmonary valve annulus diameter (MPVD) was (2.34±0.21) cm.All patients had normal pulmonary valves.The New York Heart Association (NYHA) function class was Ⅱ in 36 cases and Ⅲ in 6 cases.The operation was performed under moderate hypothermic cardiopulmonary bypass (CPB) with aortic root replacement using pulmonary autograft and pulmonary valve replacement with a homograft.Results There was no early hospital mortality.Postoperative UCG showed normal aortic valve function in all our patients.The mean gradient across the aortic valve was (6.11±0.12) mmHg.The left ventricular diastole diameter (LVDD)decreased significantly from (62±5) mm to (56±3) mm (P<0.001).The mean postoperative left ventricular ejective fraction (LVEF) was 0.49±0.23.All patients were in NYHA class Ⅰ-Ⅱ.Follow-up was completed in 38 cases for a mean period of 3.2 years (range 1-10 years).All survivors were in NYHA class Ⅰ with normal neo-aortic and pulmonary valve function.One patient died after secondary operation due to homograft fungal endocarditis 1 year after the Ross procedure.The cause of death was uncontrolled

  2. Transcatheter aortic valve implantation of the direct flow medical aortic valve with minimal or no contrast

    Energy Technology Data Exchange (ETDEWEB)

    Latib, Azeem, E-mail: alatib@gmail.com [Interventional Cardiology Unit, San Raffaele Scientific Institute and EMO-GVM Centro Cuore Columbus, Milan (Italy); Maisano, Francesco; Colombo, Antonio [Interventional Cardiology Unit, San Raffaele Scientific Institute and EMO-GVM Centro Cuore Columbus, Milan (Italy); Klugmann, Silvio [Azienda Ospedaliera Niguarda Ca Granda, Piazza Ospedale Maggiore 3, Milan (Italy); Low, Reginald; Smith, Thomas [University of California Davis, Davis, CA 95616 (United States); Davidson, Charles [Northwestern Memorial Hospital, Chicago, IL 60611 (United States); Harreld, John H. [Clinical Imaging Analytics, Guerneville, CA (United States); Bruschi, Giuseppe; DeMarco, Federico [Azienda Ospedaliera Niguarda Ca Granda, Piazza Ospedale Maggiore 3, Milan (Italy)

    2014-06-15

    The 18F Direct Flow Medical (DFM) THV has conformable sealing rings, which minimizes aortic regurgitation and permits full hemodynamic assessment of valve performance prior to permanent implantation. During the DISCOVER trial, three patients who were at risk for receiving contrast media, two due to severe CKD and one due to a recent hyperthyroid reaction to contrast, underwent DFM implantation under fluoroscopic and transesophageal guidance without aortography during either positioning or to confirm the final position. Valve positioning was based on the optimal angiographic projection as calculated by the pre-procedural multislice CT scan. Precise optimization of valve position was performed to minimize transvalve gradient and aortic regurgitation. Prior to final implantation, transvalve hemodynamics were assessed invasively and by TEE. The post-procedure mean gradients were 7, 10, 11 mm Hg. The final AVA by echo was 1.70, 1.40 and 1.68 cm{sup 2}. Total aortic regurgitation post-procedure was none or trace in all three patients. Total positioning and assessment of valve performance time was 4, 6, and 12 minutes. Contrast was only used to confirm successful percutaneous closure of the femoral access site. The total contrast dose was 5, 8, 12 cc. Baseline eGFR and creatinine was 28, 22, 74 mL/min/1.73 m{sup 2} and 2.35, 2.98, and 1.03 mg/dL, respectively. Renal function was unchanged post-procedure: eGFR = 25, 35, and 96 mL/min/1.73 m{sup 2} and creatinine = 2.58, 1.99, and 1.03 mg/dL, respectively. In conclusion, the DFM THV provides the ability to perform TAVI with minimal or no contrast. The precise and predictable implantation technique can be performed with fluoro and echo guidance.

  3. Association Between Left Atrial Dilatation and Invasive Hemodynamics at Rest and During Exercise in Asymptomatic Aortic Stenosis

    DEFF Research Database (Denmark)

    Christensen, Nicolaj Lyhne; Dahl, Jordi Sanchez; Carter-Storch, Rasmus

    2016-01-01

    BACKGROUND: Transition from an asymptomatic to symptomatic state in severe aortic stenosis is often difficult to assess. Identification of a morphological sign of increased hemodynamic load may be important in asymptomatic aortic stenosis to identify patients at risk. METHODS AND RESULTS: Thirty......-nine patients with asymptomatic severe aortic stenosis (aortic valve area 3.5 m/s) underwent exercise testing with simultaneous invasive hemodynamic monitoring and Doppler echocardiography. Cardiac index, pulmonary artery pressure, and pulmonary capillary wedge pressure (PCWP) were.......92-4.15). CONCLUSIONS: LA size reflects hemodynamic burden in patients with asymptomatic severe aortic stenosis. Quantitative measurements of LA and diastolic function are associated with left ventricular filling pressures with exercise and could be used to identify asymptomatic patients with increased hemodynamic...

  4. Aortic valve replacement for aortic stenosis with a small aortic annulus in a patient having Werner's syndrome and liver cirrhosis.

    Science.gov (United States)

    Sogawa, M; Kasuya, S; Yamamoto, K; Koshika, M; Oguma, F; Hayashi, J

    2001-12-01

    Werner's syndrome is a rare genetic disease characterized by premature aging and scleroderma-like involvement of the skin. We report a case of aortic valve replacement for severely calcified aortic valve stenosis with a small annulus in a patient suffering from Werner's syndrome and liver cirrhosis

  5. Rapid donor liver procurement with only aortic perfusion

    Institute of Scientific and Technical Information of China (English)

    Qi-Yuan Lin; KK Chui; AR-Nitin Rao

    2001-01-01

    ATM: to describe a rapid technique for procurement of donor liver with aortic perfusion only (APO). METHODS: Only the aorta is cannulated and perfused with chilled preservation solution. RESULTS: The quality of donor liver can ensure the grafted liver functions. CONCLUSION: The method of APO can simplify the operative procedure, compared with the dual cannulation. It also can minimize the danger of injuring vascular structures and involve less dissection.

  6. Surgery for abdominal aortic aneurysms. A survey of 656 patients

    DEFF Research Database (Denmark)

    Olsen, P S; Schroeder, T; Agerskov, Kim

    1991-01-01

    Between 1979 and 1988, 656 patients were operated upon for abdominal aortic aneurysm. Elective operation was performed in 287 patients (44%) and acute operation in 369 patients. A ruptured aneurysm was found in 218 patients (33%). Patients with arteriosclerotic heart disease, hypertension, impaired...... renal function or chronic pulmonary disease showed an increased perioperative mortality. Development of postoperative cardiac and renal complications could not be related to previous cardiac or renal diseases. The major postoperative complications were renal failure in 81 patients (12%), pulmonary...

  7. Biomarkers of Hemodynamic Stress and Aortic Stiffness after STEMI: A Cross-Sectional Analysis

    Directory of Open Access Journals (Sweden)

    Sebastian Johannes Reinstadler

    2015-01-01

    Full Text Available Aim. Increased aortic stiffness might adversely affect cardiac structure, function, and perfusion. Release of biomarkers of hemodynamic stress is thought to be enhanced by these alterations. We aimed to evaluate the association between biomarkers of hemodynamic stress and aortic stiffness assessed at a chronic stage after ST-segment elevation myocardial infarction (STEMI. Methods. Fifty-four patients four months after STEMI were enrolled in this cross-sectional, single-center study. N-terminal pro–B-type natriuretic peptide (NT-proBNP, mid-regional pro–A-type natriuretic peptide (MR-proANP, and mid-regional proadrenomedullin (MR-proADM levels were measured by established assays. Aortic stiffness was assessed by the measurement of pulse wave velocity using phase-contrast cardiovascular magnetic resonance. Results. NT-proBNP, MR-proANP, and MR-proADM concentrations were all correlated with aortic stiffness in univariate analysis (r=0.378, r=0.425, and r=0.532; all P<0.005, resp.. In multiple linear regression analysis, NT-proBNP (β=0.316, P=0.005 and MR-proADM (β=0.284, P<0.020 levels were associated with increased aortic stiffness independently of age, blood pressure, and renal function. NT-proBNP was the strongest predictor for high aortic stiffness (area under the curve: 0.82, 95% CI 0.67–0.96. Conclusion. At a chronic stage after STEMI, concentrations of biomarkers for hemodynamic stress, especially NT-proBNP, are positively correlated with aortic stiffness. These biomarkers might also be useful as predictors of high aortic stiffness after STEMI.

  8. Altered Smooth Muscle Cell Force Generation as a Driver of Thoracic Aortic Aneurysms and Dissections.

    Science.gov (United States)

    Milewicz, Dianna M; Trybus, Kathleen M; Guo, Dong-Chuan; Sweeney, H Lee; Regalado, Ellen; Kamm, Kristine; Stull, James T

    2017-01-01

    The importance of maintaining contractile function in aortic smooth muscle cells (SMCs) is evident by the fact that heterozygous mutations in the major structural proteins or kinases controlling contraction lead to the formation of aneurysms of the ascending thoracic aorta that predispose to life-threatening aortic dissections. Force generation by SMC requires ATP-dependent cyclic interactions between filaments composed of SMC-specific isoforms of α-actin (encoded by ACTA2) and myosin heavy chain (MYH11). ACTA2 and MYH11 mutations are predicted or have been shown to disrupt this cyclic interaction predispose to thoracic aortic disease. Movement of the myosin motor domain is controlled by phosphorylation of the regulatory light chain on the myosin filament, and loss-of-function mutations in the dedicated kinase for this phosphorylation, myosin light chain kinase (MYLK) also predispose to thoracic aortic disease. Finally, a mutation in the cGMP-activated protein kinase (PRKG1) results in constitutive activation of the kinase in the absence of cGMP, thus driving SMC relaxation in part through increased dephosphorylation of the regulatory light chain and predisposes to thoracic aortic disease. Furthermore, SMCs cannot generate force without connections to the extracellular matrix through focal adhesions, and mutations in the major protein in the extracellular matrix, fibrillin-1, linking SMCs to the matrix also cause thoracic aortic disease in individuals with Marfan syndrome. Thus, disruption of the ability of the aortic SMC to generate force through the elastin-contractile units in response to pulsatile blood flow may be a primary driver for thoracic aortic aneurysms and dissections.

  9. [Unicuspid Aortic Valve Stenosis Combined with Aortic Coarctation;Report of a Case].

    Science.gov (United States)

    Kubota, Takehiro; Wakasa, Satoru; Shingu, Yasushige; Matsui, Yoshiro

    2016-06-01

    Unicuspid aortic valve in an adult is extremely rare. In addition, 90% of the patients with aortic coarctation are reported to die before the age 50. A 60-year-old woman was admitted to our hospital for further examination of exertional dyspnea which had begun one year before. She had been under medical treatment for hypertension since early thirties, and had been also diagnosed with moderate aortic stenosis at 50 years of age. She was at 1st diagnosed with aortic coarctation combined with bicuspid aortic valve stenosis. The aortic valve was then found unicuspid and was replaced under cardiopulmonary bypass with perfusion to both the ascending aorta and the femoral artery. Repair of aortic coarctation was performed 3 months later through left thoracotomy without extracorporeal circulation due to the rich collateral circulation. She had no postoperative complications, and hypertension as well as ankle-brachial index improved to the normal levels.

  10. Severe aortic stenosis: diagnosis, treatment and prognosis

    NARCIS (Netherlands)

    M.W.A. van Geldorp (Martijn)

    2013-01-01

    textabstractDegenerative aortic stenosis is the most common valvular heart disease in developed countries. The prevalence of severe aortic stenosis increases with age from 1% in people below 65 years of age to nearly 6% in people over the age of 85. Since the population life expectancy continues to

  11. Transcatheter Aortic Valve Replacement in Europe

    DEFF Research Database (Denmark)

    Mylotte, Darren; Osnabrugge, Ruben L J; Windecker, Stephan;

    2013-01-01

    The authors sought to examine the adoption of transcatheter aortic valve replacement (TAVR) in Western Europe and investigate factors that may influence the heterogeneous use of this therapy.......The authors sought to examine the adoption of transcatheter aortic valve replacement (TAVR) in Western Europe and investigate factors that may influence the heterogeneous use of this therapy....

  12. Thoracic aortic catastrophes : towards the endovascular solution

    NARCIS (Netherlands)

    Jonker, F.H.W.

    2010-01-01

    Descending thoracic aortic catastrophes include a variety of acute pathologies of the descending thoracic aorta, which are all associated with high morbidity and mortality rates, requiring immediate intervention. For this thesis, we explored the management and outcomes of several thoracic aortic cat

  13. Thoraco-abdominal aortic aneurysm branched repair

    NARCIS (Netherlands)

    Verhoeven, E. L. G.; Tielliu, I. F. J.; Ferreira, M.; Zipfel, B.; Adam, D. J.

    2010-01-01

    Open thoraco-abdominal aortic aneurysm repair is a demanding procedure with high impact on the patient and the operating team. Results from expert centres show mortality rates between 3-21%, with extensive morbidity including renal failure and paraplegia. Endovascular repair of abdominal aortic aneu

  14. Regge-like initial input and evolution of non-singlet structure functions from DGLAP equation up to next-next-to-leading order at low and low 2

    Indian Academy of Sciences (India)

    Nayan Mani Nath; Mrinal Kumar Das; Jayanta Kumar Sarma

    2015-10-01

    This is an attempt to study how the features of Regge theory, along with QCD predictions, lead towards the understanding of unpolarized non-singlet structure functions $F_{2}^{\\text{NS}}$ (, 2) and 3 (, 2) at low and low 2 . Combining the features of perturbative quantum chromodynamics (pQCD) and Regge theory, an ansatz for $F_{2}^{\\text{NS}}$ (, 2) and 3 (, 2) structure functions at small was obtained, which when used as the initial input to Dokshitzer–Gribov–Lipatov–Altarelli–Parisi (DGLAP) equation, gives the 2 evolution of the non-singlet structure functions. The non-singlet structure functions, evolved in accordance with DGLAP evolution equations up to next-next-to-leading order are studied phenomenologically in comparison with the available experimental and parametrization results taken from NMC, CCFR, NuTeV, CORUS, CDHSW, NNPDF and MSTW Collaborations and a very good agreement is observed in this regard.

  15. Valvular and aortic diseases in osteogenesis imperfecta.

    Science.gov (United States)

    Lamanna, Arvin; Fayers, Trevor; Clarke, Sophie; Parsonage, William

    2013-10-01

    Osteogenesis imperfecta (OI) is an inheritable connective tissue disorder caused by defective collagen synthesis with the principal manifestations of bone fragility. OI has been associated with left sided valvular regurgitation and aortic dilation. Valve and aortic surgery are technically feasible in patients with OI but are inherently high risk due to the underlying connective tissue defect. This report reviews the valvular and aortic pathology associated with OI and their management. We describe two cases of patients with OI who have significant aortic and mitral valve regurgitation, one of whom has been managed conservatively and the other who has undergone successful mitral valve repair and aortic valve replacement. The latter case represents the fifth case of mitral valve repair in a patient with OI reported in the medical literature.

  16. Stroke in Patients With Aortic Stenosis

    DEFF Research Database (Denmark)

    Greve, Anders Møller; Dalsgaard, Morten; Bang, Casper N

    2014-01-01

    BACKGROUND AND PURPOSE: There are limited data on risk stratification of stroke in aortic stenosis. This study examined predictors of stroke in aortic stenosis, the prognostic implications of stroke, and how aortic valve replacement (AVR) with or without concomitant coronary artery bypass grafting...... influenced the predicted outcomes. METHODS: Patients with mild-to-moderate aortic stenosis enrolled in the Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) study. Diabetes mellitus, known atherosclerotic disease, and oral anticoagulation were exclusion criteria. Ischemic stroke was the primary end point...... death (HR, 8.1; 95% CI, 4.7-14.0; Paortic stenosis not prescribed oral anticoagulation, atrial fibrillation, AVR with concomitant coronary artery bypass grafting, and CHA2DS2-VASc score were the major predictors of stroke. Incident stroke was strongly associated...

  17. Transcatheter aortic valve replacement in elderly patients

    Institute of Scientific and Technical Information of China (English)

    Dimytri Siqueira; Alexandre Abizaid; Magaly Arrais J.; Eduardo Sousa

    2012-01-01

    Aortic stenosis is the most common native valve disease, affecting up to 5% of the elderly population. Surgical aortic valve replacement reduces symptoms and improves survival, and is the definitive therapy in patients with symptomatic severe aortic stenosis. However, despite the good results of classic surgery, risk is markedly increased in elderly patients with co-morbidities. Transcatheter aortic valve replacement (TAVR) allows implantation of a prosthetic heart valve within the diseased native aortic valve without the need for open heart surgery and cardiopulmonary bypass, offering a new therapeutic option to elderly patients considered at high surgical risk or with contraindications to surgery. To date, several multicenter registries and a randomized trial have confirmed the safety and efficacy of TAVR in those patients. In this chapter, we review the background and clinical applications of TAVR in elderly patients.

  18. [Modern aortic surgery in Marfan syndrome--2011].

    Science.gov (United States)

    Kallenbach, K; Schwill, S; Karck, M

    2011-09-01

    Marfan syndrome is a hereditary disease with a prevalence of 2-3 in 10,000 births, leading to a fibrillin connective tissue disorder with manifestations in the skeleton, eye, skin, dura mater and in particular the cardiovascular system. Since other syndromes demonstrate similar vascular manifestations, but therapy may differ significantly, diagnosis should be established using the revised Ghent nosology in combination with genotypic analysis in specialized Marfan centres. The formation of aortic root aneurysms with the subsequent risk of acute aortic dissection type A (AADA) or aortic rupture limits life expectancy in patients with Marfan syndrome. Therefore, prophylactic replacement of the aortic root needs to be performed before the catastrophic event of AADA can occur. The goal of surgery is the complete resection of pathological aortic tissue. This can be achieved with excellent results by using a (mechanically) valved conduit that replaces both the aortic valve and the aortic root (Bentall operation). However, the need for lifelong anticoagulation with Coumadin can be avoided using the aortic valve sparing reimplantation technique according to David. The long-term durability of the reconstructed valve is favourable, and further technical improvements may improve longevity. Although results of prospective randomised long-term studies comparing surgical techniques are lacking, the David operation has become the surgical method of choice for aortic root aneurysms, not only at the Heidelberg Marfan Centre. Replacement of the aneurysmal dilated aortic arch is performed under moderate hypothermic circulatory arrest combined with antegrade cerebral perfusion using a heart-lung machine, which we also use in thoracic or thoracoabdominal aneurysms. Close post-operative follow-up in a Marfan centre is pivotal for the early detection of pathological changes on the diseased aorta.

  19. Reoperation on aortic disease in patients with previous aortic valve surgery

    Institute of Scientific and Technical Information of China (English)

    SUN Xiao-gang; ZHANG Liang; YU Cun-tao; QIAN Xiang-yang; CHANG Qian

    2013-01-01

    Background Aortic valve replacement (AVR) is a safe and effective method in the treatment of aortic valve diseases.This study aimed to increase the understanding on re-treatment of aortic diseases after aortic valve surgery through a retrospective analysis of 47 related cases.Methods Forty-seven patients (38 males and 9 females) with previous aortic valve surgery have received reoperation on aorta from January 2003 to June 2012,and the mean interval time of re-intervention to aortic disease was 6 years ((6.0± 3.8) years).The secondary aortic surgery included aortic root replacement (14 cases),ascending aorta replacement (10 cases),aortic root/ascending aorta plus total arch replacement with stented elephant trunk implantation (21 cases),and total thoracoabdominal aorta replacement (2 cases).All these patients have received outpatient re-exams or follow-up by phone calls.Results After the initial aortic valve replacement,patients suffered from aortic dissection (25 cases,53%),ascending aortic aneurysm (12 cases,26%) or aortic root aneurysm (10 cases,21%).Diameter in ascending aorta increased (5.2±7.1) mm per year and aortic sinus (3.3±3.1) mm per year.The annual growth value of diameter in ascending aorta was higher in patients with rheumatic heart disease than that in Marfan syndrome (P<0.05).All 47 patients have received reoperation on aorta.One patient died in operating room because aortic dissection seriously involved right coronary artery.Seven patients had renal insufficiency after operation; neurological complications occurred in 14 patients including 7 patients with stroke and the others with transient brain dysfunction.All patients were followed up,the mean survival time was (97.25±17.63) months,95% confidence interval was 55.24-73.33 months.Eight cases were died during follow-up and five-year survival rate was 83%.Conclusion To reduce the aortic adverse events after first aortic valve surgery,it is necessary to actively treat and strictly

  20. Aortic Stenosis: Evaluation with Multidetector CT Angiography and MR Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Eun Ju; Choi, Sang Il; Lim, Cheong; Park, Kye Hyun; Chang, Hyuk Jae; Choi, Dong Ju [Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Kim, Dong Hun [Soonchunhyang University Bucheon Hospital, Bucheon (Korea, Republic of); Lee, Whal; Park, Jae Hyung [Seoul National University Hospital, Seoul (Korea, Republic of)

    2008-10-15

    Aortic valvular stenosis (AS) is the most common valve disease which results in the need for a valve replacement. Although a Doppler echocardiography is the current reference imaging method, the multidetector computerized tomography (MDCT) and magnetic resonance imaging (MRI) have recently emerged as a promising method for noninvasive valve imaging. In this study, we briefly describe the usefulness and comparative merits of the MDCT and MRI for the evaluation of AS in terms of valvular morphology (as the causes of AS), quantification of aortic valve area, pressure gradient of flow (for assessment severity of AS), and the evaluation of the ascending aorta and cardiac function (as the secondary effects of AS). The familiarity with the MDCT and MRI features of AS is considered to be helpful for the accurate diagnosis and proper management of patients with a poor acoustic window.

  1. Quantitative image analysis for planning of aortic valve replacement

    NARCIS (Netherlands)

    Elattar, M.A.I.M.

    2016-01-01

    Aortic stenosis is the most common and frequent cause of sudden death among all valvular heart diseases. Symptomatic aortic stenosis is considered to be a fatal disease if left untreated. Aortic valve replacement is the mainstay of treatment of symptomatic aortic stenosis. Traditional treatment of s

  2. Aortic root size and prevalence of aortic regurgitation in elite strength trained athletes.

    Science.gov (United States)

    Babaee Bigi, Mohammad Ali; Aslani, Amir

    2007-08-01

    Athletes involved in mainly static or isometric exercise (e.g., weight lifting, power lifting, and bodybuilding) develop pressure overloads due to the high systemic arterial pressure found in this type of exercise. It is hypothesized that chronically elevated aortic wall tension in strength-trained athletes is associated with aortic dilatation and regurgitation. The aim of this study was to evaluate aortic root size and the prevalence of aortic regurgitation in elite strength-trained athletes. The cohort included 100 male athletes (mean age 22.1 +/- 3.6 years; all were finalists or medalists in the country) and 128 healthy age- and height-matched subjects (the control group). Aortic root diameters at end-diastole were measured at 4 locations: (1) the aortic annulus, (2) the sinuses of Valsalva, (3) the sinotubular junction, and (4) the maximal diameter of the proximal ascending aorta. Aortic root diameters at all levels were significantly greater in the strength-trained athletes (p 18 and 36 and 54 months), progressive enlargement was found at all aortic diameters. In conclusion, aortic root diameters in all segments of the aortic root were significantly greater in elite strength-trained athletes compared with an age- and height-matched population.

  3. Bicuspid Aortic Valve Disease and Ascending Aortic Aneurysms: Gaps in Knowledge

    Directory of Open Access Journals (Sweden)

    Katie L. Losenno

    2012-01-01

    Full Text Available The bicuspid aortic valve is the most common congenital cardiac anomaly in developed nations. The abnormal bicuspid morphology of the aortic valve results in valvular dysfunction and subsequent hemodynamic derangements. However, the clinical presentation of bicuspid aortic valve disease remains quite heterogeneous with patients presenting from infancy to late adulthood with variable degrees of valvular stenosis and insufficiency and associated abnormalities including aortic coarctation, hypoplastic left heart structures, and ascending aortic dilatation. Emerging evidence suggests that the heterogeneous presentation of bicuspid aortic valve phenotypes may be a more complex matter related to congenital, genetic, and/or connective tissue abnormalities. Optimal management of patients with BAV disease and associated ascending aortic aneurysms often requires a thoughtful approach, carefully assessing various risk factors of the aortic valve and the aorta and discerning individual indications for ongoing surveillance, medical management, and operative intervention. We review current concepts of anatomic classification, pathophysiology, natural history, and clinical management of bicuspid aortic valve disease with associated ascending aortic aneurysms.

  4. [The thickness/radius ratio of the left ventricle in aortic stenosis. Prognostic and therapeutic implications].

    Science.gov (United States)

    Guadalajara, J F; Martínez, C; Huerta, D

    1990-01-01

    Using two-D echocardiography and cardiac catheterization we studied the performance of left ventricle in severe aortic stenosis with normal ventricular function (10 patients), and with heart failure (11 patients). With appropriate hypertrophy increased ventricular function, is found resulting in systolic wall stress normalization. When hypertrophic mechanism is unable to normalize the systolic wall stress; afterload increases with ensuing heart failure (inadequate hypertrophy). Surgical treatment in those cases reduces the afterload and increases de ventricular function. Normalization of systolic wall stress in patients with severe aortic stenosis and heart failure means irreversible myocardial damage.

  5. Two-Year Outcomes in Patients With Severe Aortic Valve Stenosis Randomized to Transcatheter Versus Surgical Aortic Valve Replacement

    DEFF Research Database (Denmark)

    Søndergaard, Lars; Steinbrüchel, Daniel Andreas; Ihlemann, Nikolaj

    2016-01-01

    BACKGROUND: The Nordic Aortic Valve Intervention (NOTION) trial was the first to randomize all-comers with severe native aortic valve stenosis to either transcatheter aortic valve replacement (TAVR) with the CoreValve self-expanding bioprosthesis or surgical aortic valve replacement (SAVR), inclu...... population. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01057173....

  6. Computational evaluation of aortic occlusion and the proposal of a novel, improved occluder: Constrained endo-aortic balloon occlusion.

    Science.gov (United States)

    de Vaal, M H; Gee, M W; Stock, U A; Wall, W A

    2016-12-01

    Because aortic occlusion is arguably one of the most dangerous aortic manipulation maneuvers during cardiac surgery in terms of perioperative ischemic neurological injury, the purpose of this investigation is to assess the structural mechanical impact resulting from the use of existing and newly proposed occluders. Existing (clinically used) occluders considered include different cross-clamps (CCs) and endo-aortic balloon occlusion (EABO). A novel occluder is also introduced, namely, constrained EABO (CEABO), which consists of applying a constrainer externally around the aorta when performing EABO. Computational solid mechanics are employed to investigate each occluder according to a comprehensive list of functional requirements. The potential of a state of occlusion is also considered for the first time. Three different constrainer designs are evaluated for CEABO. Although the CCs were responsible for the highest strains, largest deformation, and most inefficient increase of the occlusion potential, it remains the most stable, simplest, and cheapest occluder. The different CC hinge geometries resulted in poorer performance of CC used for minimally invasive procedures than conventional ones. CEABO with a profiled constrainer successfully addresses the EABO shortcomings of safety, stability, and positioning accuracy, while maintaining its complexities of operation (disadvantage) and yielding additional functionalities (advantage). Moreover, CEABO is able to achieve the previously unattainable potential to provide a clinically determinable state of occlusion. CEABO offers an attractive alternative to the shortcomings of existing occluders, with its design rooted in achieving the highest patient safety. Copyright © 2016 John Wiley & Sons, Ltd.

  7. Repair for acquired aortic valve disease.

    Science.gov (United States)

    Antunes, M J

    1996-10-01

    The favorable results of mitral valvuloplasty when compared with valve replacement have renewed the interest of many surgeons in aortic valve repair. However, these efforts have, for the most part, been unsuccessful. Also, the results of aortic valve replacement are usually better than those of mitral valve replacement. Yet, some patients appear to derive benefit from a conservative aortic valve procedure. The best examples are mild or moderate aortic valve disease associated with mitral valve or coronary artery disease, which constitute the primary indication for operation, where "prophylactic" aortic valve replacement does not appear justifiable. Other possible indications for aortic valvuloplasty includes patient's lack of compliance or contraindication to anticoagulation in young patients. Senile aortic stenosis, in very old patients with a small annulus, preserved leaflet morphology and nonsignificant commissural fusion should be considered for repair. However, since the procedure is not easily reproducible and the results not uniformly predictable, it cannot be recommended for generalized use. Nonetheless, experienced surgeons should be encouraged to continue these efforts.

  8. Aortic reconstruction with bovine pericardial grafts

    Directory of Open Access Journals (Sweden)

    Silveira Lindemberg Mota

    2003-01-01

    Full Text Available INTRODUCTION: Glutaraldehyde-treated crimped bovine pericardial grafts are currently used in aortic graft surgery. These conduits have become good options for these operations, available in different sizes and shapes and at a low cost. OBJECTIVE:To evaluate the results obtained with bovine pericardial grafts for aortic reconstruction, specially concerning late complications. METHOD: Between January 1995 and January 2002, 57 patients underwent different types of aortic reconstruction operations using bovine pericardial grafts. A total of 29 (50.8% were operated on an urgent basis (mostly acute Stanford A dissection and 28 electively. Thoracotomy was performed in three patients for descending aortic replacement (two patients and aortoplasty with a patch in one. All remaining 54 underwent sternotomy, cardiopulmonary bypass and aortic resection. Deep hypothermia and total circulatory arrest was used in acute dissections and arch operations. RESULTS: Hospital mortality was 17.5%. Follow-up was 24.09 months (18.5 to 29.8 months confidence interval and complication-free actuarial survival curve was 92.3% (standard deviation ± 10.6. Two patients lately developed thoracoabdominal aneurysms following previous DeBakey II dissection and one died from endocarditis. One "patch" aortoplasty patient developed local descending aortic pseudoaneurysm 42 months after surgery. All other patients are asymptomatic and currently clinically evaluated with echocardiography and CT scans, showing no complications. CONCLUSION: Use of bovine pericardial grafts in aortic reconstruction surgery is adequate and safe, with few complications related to the conduits.

  9. Hybrid treatment of recurring thoracoabdominal aortic aneurysm concomitant with retrograde type A aortic dissection

    Institute of Scientific and Technical Information of China (English)

    ZHANG Min-hong; GUO Wei; DU Xin; XIONG Jiang

    2010-01-01

    So far, standard therapy of complex thoracoabdominal aortic disease is open surgical repair requiring aortic clamping and replacement of the involved segment.Despite significant improvements, morbidity and mortality of open surgery remain high.I As a result, open surgery is often withheld owing to severe comorbidities of the patients. Endovascular technique has emerged as an alternative for treatment of these diseases in high risk patients,2 and has enlarged the options of treatment of complex aortic diseases. However, an endovascular approach alone is often deemed unsuitable for some complex aortic disorders because of the close proximity of the supraaortic or visceral branches. A hybrid open-endovascular approach has therefore been proposed as a viable alternative. We present here a unique patient with recurring thoracoabdominal aortic aneurysm (TAAA) concomitant with an aortic dissection (AD) treated by a hybrid open-endovascular approach.

  10. Valvular Aortic Stenosis: A Proteomic Insight

    Directory of Open Access Journals (Sweden)

    Fernando Vivanco

    2010-02-01

    Full Text Available Calcified aortic valve disease is a slowly progressive disorder that ranges from mild valve thickening with no obstruction of blood flow, known as aortic sclerosis, to severe calcification with impaired leaflet motion or aortic stenosis. In the present work we describe a rapid, reproducible and effective method to carry out proteomic analysis of stenotic human valves by conventional 2-DE and 2D-DIGE, minimizing the interference due to high calcium concentrations. Furthermore, the protocol permits the aortic stenosis proteome to be analysed, advancing our knowledge in this area. Summary: Until recently, aortic stenosis (AS was considered a passive process secondary to calcium deposition in the aortic valves. However, it has recently been highlighted that the risk factors associated with the development of calcified AS in the elderly are similar to those of coronary artery disease. Furthermore, degenerative AS shares histological characteristics with atherosclerotic plaques, leading to the suggestion that calcified aortic valve disease is a chronic inflammatory process similar to atherosclerosis. Nevertheless, certain data does not fit with this theory making it necessary to further study this pathology. The aim of this study is to develop an effective protein extraction protocol for aortic stenosis valves such that proteomic analyses can be performed on these structures. In the present work we have defined a rapid, reproducible and effective method to extract proteins and that is compatible with 2-DE, 2D-DIGE and MS techniques. Defining the protein profile of this tissue is an important and challenging task that will help to understand the mechanisms of physiological/pathological processes in aortic stenosis valves.

  11. Aortic stenosis: From diagnosis to optimal treatment

    Directory of Open Access Journals (Sweden)

    Tavčiovski Dragan

    2008-01-01

    Full Text Available Aortic stenosis is the most frequent valvular heart disease. Aortic sclerosis is the first characteristic lesion of the cusps, which is considered today as the process similar to atherosclerosis. Progression of the disease is an active process leading to forming of bone matrix and heavily calcified stiff cusps by inflammatory cells and osteopontin. It is a chronic, progressive disease which can remain asymptomatic for a long time even in the presence of severe aortic stenosis. Proper physical examination remains an essential diagnostic tool in aortic stenosis. Recognition of characteristic systolic murmur draws attention and guides further diagnosis in the right direction. Doppler echocardiography is an ideal tool to confirm diagnosis. It is well known that exercise tests help in stratification risk of asymptomatic aortic stenosis. Serial measurements of brain natriuretic peptide during a follow-up period may help to identify the optimal time for surgery. Heart catheterization is mostly restricted to preoperative evaluation of coronary arteries rather than to evaluation of the valve lesion itself. Currently, there is no ideal medical treatment for slowing down the disease progression. The first results about the effect of ACE inhibitors and statins in aortic sclerosis and stenosis are encouraging, but there is still not enough evidence. Onset symptoms based on current ACC/AHA/ESC recommendations are I class indication for aortic valve replacement. Aortic valve can be replaced with a biological or prosthetic valve. There is a possibility of percutaneous aortic valve implantation and transapical operation for patients that are contraindicated for standard cardiac surgery.

  12. Statistical identification of effective input variables. [SCREEN

    Energy Technology Data Exchange (ETDEWEB)

    Vaurio, J.K.

    1982-09-01

    A statistical sensitivity analysis procedure has been developed for ranking the input data of large computer codes in the order of sensitivity-importance. The method is economical for large codes with many input variables, since it uses a relatively small number of computer runs. No prior judgemental elimination of input variables is needed. The sceening method is based on stagewise correlation and extensive regression analysis of output values calculated with selected input value combinations. The regression process deals with multivariate nonlinear functions, and statistical tests are also available for identifying input variables that contribute to threshold effects, i.e., discontinuities in the output variables. A computer code SCREEN has been developed for implementing the screening techniques. The efficiency has been demonstrated by several examples and applied to a fast reactor safety analysis code (Venus-II). However, the methods and the coding are general and not limited to such applications.

  13. Mycotic Aneurysm of the Aortic Arch

    Directory of Open Access Journals (Sweden)

    Ji Hye Seo

    2014-08-01

    Full Text Available A mycotic aneurysm of the thoracic aorta is rare. We report a case of mycotic aneurysm that developed in the aortic arch. An 86-year-old man was admitted with fever and general weakness. Blood culture yielded methicillin-resistant Staphylococcus aureus. Chest X-ray showed an enlarged aortic arch, and computed tomography scan revealed an aneurysm in the aortic arch. The patient was treated only with antibiotics and not surgically. The size of the aneurysm increased rapidly, resulting in bronchial obstruction and superimposed pneumonia. The patient died of respiratory failure.

  14. Bacillus cereus endocarditis in native aortic valve.

    Science.gov (United States)

    Ngow, H A; Wan Khairina, W M N

    2013-02-01

    Bacillus cereus endocarditis is rare. It has been implicated in immunocompromised individuals, especially in intravenous drug users as well as in those with a cardiac prosthesis. The patient was a 31-year-old ex-intravenous drug addict with a past history of staphylococcal pulmonary valve endocarditis, who presented with symptoms of decompensated cardiac failure. Echocardiography showed severe aortic regurgitation with an oscillating vegetation seen on the right coronary cusp of the aortic valve. The blood cultures grew Bacillus cereus. We report this as a rare case of Bacillus cereus endocarditis affecting a native aortic valve.

  15. The future of aortic surgery in Europe

    DEFF Research Database (Denmark)

    Czerny, Martin; Bachet, Jean; Bavaria, Joseph;

    2012-01-01

    the interested reader with an overview of how aortic surgery and (perhaps more accurately) aortic medicine has evolved in Europe, and its present standing; also to provide a glimpse into the future, trying to disseminate the thoughts of a group of people actively involved in the development of aortic medicine......At least every ten years, each specialty should reflect upon its past, its present and its future, in order to be able to reconfirm the direction in which it is headed, to adopt suggestions from inside and outside and, consequently, to improve. As such, the aim of this manuscript is to provide...

  16. [Paradigm shifts in aortic pathology: clinical and therapeutic implications. Clinical imaging in chronic and acute aortic syndromes. The aorta as a cause of cardiac disease].

    Science.gov (United States)

    Nistri, Stefano; Roghi, Alberto; Mele, Donato; Biagini, Elena; Chiodi, Elisabetta; Colombo, Ettore; d'Amati, Giulia; Leone, Ornella; Angelini, Annalisa; Basso, Cristina; Pepe, Guglielmina; Rapezzi, Claudio; Thiene, Gaetano

    2014-06-01

    Multimodal imaging plays a pivotal role in the assessment of the thoracic aorta, both in chronic and acute settings. Moving from improved knowledge on the structure and function of the aortic wall, as well as on its pathophysiology and histopathology, appropriate utilization of each imaging modality results into a better definition of the patient's need and proper treatment strategy. This review is aimed at highlighting the most critical aspects in this field, providing cardiologists with some novel clues for the imaging approach to patients with thoracic aortic disease.

  17. Stent graft implantation in an aortic pseudoaneurysm associated with a fractured Cheatham-Platinum stent in aortic coarctation.

    Science.gov (United States)

    Kuhelj, Dimitrij; Berden, Pavel; Podnar, Tomaž

    2016-03-01

    We report a case of aortic pseudoaneurysm associated with a fractured bare Cheatham-Platinum stent following stenting for aortic coarctation. These complications were recognised 6 years after the implantation procedure and were successfully managed by percutaneous stent graft implantation. Staged approach for stent dilatation might prevent development of aortic pseudoaneurysms. In addition, careful follow-up is warranted after stenting for aortic coarctation, particularly in patients with recognised aortic wall injury.

  18. [Minimally invasive cardiac surgery for aortic valve disease].

    Science.gov (United States)

    Fujimura, Y; Katoh, T; Hamano, K; Gohra, H; Tsuboi, H; Esato, K

    1998-12-01

    Recent surgical advances leading to good operative results have contributed to the trend to useminimally invasive approaches, even in cardiac surgery. Smaller incisions are clearly more cosmetically acceptable to patients. When using a minimally invasive approach, it is most important to maintain surgical quality without jeopardizing patients. A good operative visual field leads to good surgical results. In the parasternal approach, we use a retractor to harvest an internal thoracic artery in coronary artery bypass surgery. Retracting the sternum upward allows for a good surgical view and permits the use of an arch cannula rather than femoral cannulation. When reoperating for aortic valve repair, the j-sternotomy approach requires less adhesiolysis compared with the traditional full sternotomy. No special technique is necessary to perform aortic valve surgery using the j-sternotomy approach. However, meticulous attention must be paid to avoiding left ventricular air embolisms to prevent postoperative stroke or neurocognitive deficits, especially when utilizing a minimally invasive approach. Transesophageal echo is useful not only for monitoring cardiac function but also for monitoring the persence of air in the left ventricle and atrium. This paper compare as the degree of invasion of minimally invasive cardiac surgery and the traditional full sternotomy. No differences were found in the occurrence of systemic inflammatory response syndrome between patients undergoing minimally invasive cardiac surgery and the traditional technique. Therefore it is concluded that minimally invasive surgery for patients with aortic valve disease may become the standard approach in the near future.

  19. Patient-prosthesis mismatch: surgical aortic valve replacement versus transcatheter aortic valve replacement in high risk patients with aortic stenosis.

    Science.gov (United States)

    Ghanta, Ravi K; Kron, Irving L

    2016-10-01

    Patient prosthesis mismatch (PPM) can occur when a prosthetic aortic valve has an effective orifice area (EOA) less than that of a native valve. A recent study by Zorn and colleagues evaluated the incidence and significance of PPM in high risk patients with severe aortic stenosis who were randomized to transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR). TAVR is associated with decreased incidence of severe PPM compared to traditional SAVR valves. Severe PPM increases risk for death at 1 year postoperatively in high risk patients. The increased incidence of PPM is largely due to differences in valve design and should encourage development of newer SAVR valves to reduce risk for PPM. In addition more vigorous approaches to root enlargement in small annulus should be performed with SAVR to prevent PPM.

  20. Rapid Deployment Aortic Replacement (RADAR) Registry in Spain: a protocol

    Science.gov (United States)

    Cal-Purriños, Natalia; Arribas-Leal, Jose M; Carnero-Alcazar, Manuel; Gutierrez-Diez, Jose F; Cuenca-Castillo, Jose J

    2017-01-01

    Introduction Rapid deployment valves (RDV) represent a newly introduced approach to aortic valve replacement which facilitates surgical implantation and minimally invasive techniques, shortens surgical times and shows excellent haemodynamic performance. However, evidence on their safety, efficacy and potential complications is mostly fitted with small-volume and retrospective studies. Moreover, no current guidelines exist. To improve our knowledge on this technology, The Rapid Deployment Aortic Replacement (RADAR) Registry will be established across Spain with the aim of assessing RDV outcomes in the real-world setting. Methods and analysis The RADAR Registry is designed as a product registry that would provide information on its use and outcomes in clinical practice. This multicentre, prospective, national effort will initially involve 4 centres in Spain. Any patient undergoing cardiac surgery for aortic valve replacement and receiving an RDV as an isolated operation or in combination with other cardiac procedures may be included. Participation is voluntary. Data collection is equal to information obtained during standard care and is prospectively entered by the participating physicians perioperatively and during subsequent follow-up visits. The primary outcome assessed is in-hospital and up to 5 years of follow-up, prosthetic valve functioning and clinical status. Secondary outcomes are to perform subgroup analysis, to compare outcomes with other existing approaches and to develop future clinical guidelines. The follow-up assessments are timed with routine clinical appointments. Dissociated data will be extracted and collectively analysed. Initial target sample size for the registry is 500 participants entered with complete follow-up information. Different substudies will be implemented within the registry to investigate specific populations undergoing aortic valve replacement. Ethics and dissemination The protocol is approved by all local institutional ethics

  1. Bilinearity in spatiotemporal integration of synaptic inputs.

    Directory of Open Access Journals (Sweden)

    Songting Li

    2014-12-01

    Full Text Available Neurons process information via integration of synaptic inputs from dendrites. Many experimental results demonstrate dendritic integration could be highly nonlinear, yet few theoretical analyses have been performed to obtain a precise quantitative characterization analytically. Based on asymptotic analysis of a two-compartment passive cable model, given a pair of time-dependent synaptic conductance inputs, we derive a bilinear spatiotemporal dendritic integration rule. The summed somatic potential can be well approximated by the linear summation of the two postsynaptic potentials elicited separately, plus a third additional bilinear term proportional to their product with a proportionality coefficient [Formula: see text]. The rule is valid for a pair of synaptic inputs of all types, including excitation-inhibition, excitation-excitation, and inhibition-inhibition. In addition, the rule is valid during the whole dendritic integration process for a pair of synaptic inputs with arbitrary input time differences and input locations. The coefficient [Formula: see text] is demonstrated to be nearly independent of the input strengths but is dependent on input times and input locations. This rule is then verified through simulation of a realistic pyramidal neuron model and in electrophysiological experiments of rat hippocampal CA1 neurons. The rule is further generalized to describe the spatiotemporal dendritic integration of multiple excitatory and inhibitory synaptic inputs. The integration of multiple inputs can be decomposed into the sum of all possible pairwise integration, where each paired integration obeys the bilinear rule. This decomposition leads to a graph representation of dendritic integration, which can be viewed as functionally sparse.

  2. An abdominal aortic calcification as a RISK FACTOR FOR cardio -cerebral events in patients with peripheral arterial

    Directory of Open Access Journals (Sweden)

    V. A. Zelinskiy

    2012-01-01

    Full Text Available Background. The patients with abdominal aortic calcification have a high risk of cardiocerebral events, but the pathways of them have not been reported so far. The goal of our study was to assess the structure and function of myocardium and to determine the morphological features of carotid artery atherosclerosis in patients with abdominal aortic calcification.Materials and methods. A total of 167 executive patients with peripheral arterial disease were enrolled in study. The study group included 85 patients with abdominal aortic calcification (men – 95.3 %; age median was – 66.6 ± 12. Control group included 82 patients without objective signs of abdominal aortic calcification. Abdominal aortic calcification was detected by CT imaging. All patients have undergone echocardiography and duplex scanning of carotid arteries.Results. Prevalence and severity of ischemic heart disease and cerebrovascular disease were statistically significant higher in patients with abdominal aortic calcification (91.7, 65.8 % vs. 67, 37.3 % (р < 0.01. We have found statistically significant differences between groupsin heart structure and function. A high left ventricular wall thickness (р < 0.01, left atrium dilation (р < 0.01 and enhanced of left ventricular mass (р < 0.05, ejection fraction reduction (р < 0.05 and more common diastolic dysfunction (р < 0.05 were determined inpatients with abdominal aortic calcification. An intima-media thickness of the common carotid artery was significantly higher in study group patients (1.38 ± 0.07 mm vs. 1.14 ± 0.06 mm (р < 0.001.Conclusion. Our findings suggested that abdominal aortic calcification is main reason of hypertrophy and dilation in the left heart due to enhanced peripheral resistance. Hypertrophy and dilation in the left heart is provided a high risk of cardiovascular events in patients withabdominal aortic calcification.

  3. Assessment of left ventricular global and regional systolic function after transcatheter aortic valve implantation by three-dimensional speckle tracking imaging%三维斑点追踪技术评价经导管主动脉瓣植入术患者左心室整体及局部收缩功能

    Institute of Scientific and Technical Information of China (English)

    陈丽萍; 魏薪; 冯沅; 陈茂; 唐红

    2014-01-01

    Objective To investigate the alternation of left ventricular systolic function in patients underwent transcatheter aortic valve implantation operation(TAVI) by three-dimensional speckle tracking technology (3D-STI).Methods Totally 20 patients with severe aortic stenosis were enrolled.All the subjects underwent successful TAVI operation.The real-time 3D full volume datasets on apical four-chamber view were acquired on before,7 days and 1 month after TAVI.Left ventricular global longitudinal strain(GLS),regional peak systolic longitudinal strain(LS),regional peak systolic circumferential strain(CS) and regional peak systolic radial strain(RS),were analysed using off-line TomTec software,the differences among the three groups were compared.Results Compared with the preoperation,aortic valve blood flow velocity (AV),mean aortic valve pressure gradient(mPAG) of 7 days after operation decreased significantly.Threedimensional left ventricular ejecation fraction(3D-LVEF) among the patients whose 3D-LVEF under 50%had a remarkable increase and whose 3D-LVEF exceed 50% before operation had no significant change,while 1 month after operation the 3D-LVEF had a significant improvement compared with the preoperational data regardless of 3D-LVEF under 50% or not.The GLS and LS of all segments of 7 days after TAVI were higher than pre-operation(all P <0.05),and it had a further improvement 1 month after TAVI.Conclusions LV systolic function had improvement early after TAVI.3D-STI is a new,convenient way to detect the global and regional left ventricular systolic function of TAVI patients.%目的 应用三维斑点追踪显像(three-dimensional speckle tracking imaging,3D-STI)技术评估主动脉瓣狭窄(aortic stenosis,AS)患者经导管主动脉瓣植入(transcatheter aortic valve implantation,TAVI)术后左室整体及局部收缩功能变化.方法 20例在我院行TAVI术的重度AS患者,采集术前、术后7d及术后1月标准心尖四腔观三维图,运用TomTec

  4. Dual source multidetector CT-angiography before transcatheter aortic valve implantation (TAVI) using a high-pitch spiral acquisition mode

    Energy Technology Data Exchange (ETDEWEB)

    Wuest, W.; Anders, K.; May, M.S.; Uder, M. [University of Erlangen, Department of Radiology, Erlangen (Germany); Schuhbaeck, A.; Gauss, S.; Marwan, M.; Arnold, M.; Muschiol, G.; Daniel, W.G.; Achenbach, S. [University of Erlangen, Department of Cardiology, Erlangen (Germany); Ensminger, S. [University of Erlangen, Department of Cardiac Surgery, Erlangen (Germany)

    2012-01-15

    Transcatheter Aortic Valve Implantation (TAVI) is an alternative to surgical valve replacement in high risk patients. Angiography of the aortic root, aorta and iliac arteries is required to select suitable candidates, but contrast agents can be harmful due to impaired renal function. We evaluated ECG-triggered high-pitch spiral dual source Computed Tomography (CT) with minimized volume of contrast agent to assess aortic root anatomy and vascular access. 42 patients (82 {+-} 6 years) scheduled for TAVI underwent dual source (DS) CT angiography (CTA) of the aorta using a prospectively ECG-triggered high-pitch spiral mode (pitch = 3.4) with 40 mL iodinated contrast agent. We analyzed aortic root/iliac dimensions, attenuation, contrast to noise ratio (CNR), image noise and radiation exposure. Aortic root/iliac dimensions and distance of coronary ostia from the annulus could be determined in all cases. Mean aortic and iliac artery attenuation was 320 {+-} 70 HU and 340 {+-} 77 HU. Aortic/iliac CNR was 21.7 {+-} 6.8 HU and 14.5 {+-} 5.4 HU using 100 kV (18.8 {+-} 4.1 HU and 8.7 {+-} 2.6 HU using 120 kV). Mean effective dose was 4.5 {+-} 1.2 mSv. High-pitch spiral DSCTA can be used to assess the entire aorta and iliac arteries in TAVI candidates with a low volume of contrast agent while preserving diagnostic image quality. (orig.)

  5. Dissecting aortic aneurysm in maintenance hemodialysis patients

    Directory of Open Access Journals (Sweden)

    Ounissi M

    2009-01-01

    Full Text Available The dissecting aortic aneurysm (DAA is a rare pathology that may result in fatal outcome. We report follow up of three cases of DAA patients undergoing maintenance hemo-dialysis who were managed conservatively.

  6. Valve selection in aortic valve endocarditis

    Science.gov (United States)

    Zubrytska, Yana

    2016-01-01

    Aortic prosthetic valve endocarditis (PVE) is a potentially life-threatening disease. Mortality and incidence of infective endocarditis have been reduced in the past 30 years. Medical treatment of aortic PVE may be successful in patients who have a prompt response after antibiotic treatment and who do not have prosthetic dysfunction. In advanced stages, antibiotic therapy alone is insufficient to control the disease, and surgical intervention is necessary. Surgical treatment may be lifesaving, but it is still associated with considerable morbidity and mortality. The aim of surgery is to perform a radical excision of all infected and necrotic tissue, reconstruction of the left ventricle outflow tract, and replacement of the aortic valve. There is no unanimous consensus on which is the optimal prosthesis to implant in this context, and several surgical techniques have been suggested. We aim to analyze the efficacy of the surgical treatment and discuss the issue of valve selection in patients with aortic valve endocarditis.

  7. Type B Aortic Dissection: Management Updates

    Directory of Open Access Journals (Sweden)

    Naghmeh Moshtaghi

    2009-12-01

    Full Text Available Acute aortic dissection (AAD is the most frequent catastrophic event of the aorta; it occurs nearly three times as frequently as the rupture of abdominal aortic aneurysm. Sixty percent of dissection cases are classified as proximal or type A and 40% as distal or type B, according to the Stanford Classification. The most frequent causes of death in acute type B dissection are aortic rupture and malperfusion syndrome.We herein review recent data suggesting different management modalities of type B aortic dissection, including medical, surgical, and endovascular treatments. Although medical therapy is still the standard approach in uncomplicated cases, there are subgroups of patients who may benefit from endovascular management. Endovascular techniques or surgery are valuable options for complicated cases. Hybrid suites, multidisciplinary approaches, and good imaging techniques can be considered as the key to success in this regard.

  8. Medical image of the week: aortic ring

    Directory of Open Access Journals (Sweden)

    Wong C

    2014-10-01

    Full Text Available No abstract available. Article truncated after 150 words. A 78 year old man presented with altered mental status and was found to have an intraventricular hemorrhage. He was intubated for airway protection. On the post-intubation chest radiograph (Figure 1, the patient was noted to have a widening of the right paratracheal stripe. A CT chest (Figure 2 was obtained to characterize this finding and revealed an aortic ring which encircles the trachea and esophagus. Vascular rings are uncommon congenital abnormalities, accounting for approximately 1% of congenital heart disease. Complete vascular rings can occur with a right aortic arch with a ligamentum arteriosum or with a double aortic arch, such as with our patient (1. This ring can cause airway compression, stridor, esophageal compression, or no symptoms at all. As the embryo develops, the left fourth pharyngeal arch normally persists to become the aortic arch while the right fourth pharyngeal arch regresses. If both fourth pharyngeal arches persist, a ...

  9. Global Strain in Severe Aortic Valve Stenosis

    DEFF Research Database (Denmark)

    Dahl, Jordi S; Videbæk, Lars; Poulsen, Mikael K

    2012-01-01

    BACKGROUND: -Global longitudinal systolic strain (GLS) is often reduced in aortic stenosis despite normal ejection fraction. The importance of reduced preoperative GLS on long-term outcome after aortic valve replacement (AVR) is unknown. METHODS AND RESULTS: -A total of 125 patients with severe...... aortic stenosis and ejection fraction >40% scheduled for AVR were evaluated preoperatively and divided into 4 groups according to GLS quartiles. Patients were followed up for 4 years. The primary endpoint was major adverse cardiac events (MACE) defined as cardiovascular mortality and cardiac......Score, history with ischemic heart disease and ejection fraction. CONCLUSIONS: -In patients with symptomatic severe aortic stenosis undergoing AVR reduced GLS provides important prognostic information beyond standard risk factors. Clinical Trial Registration-URL: http://www.clinicaltrial.gov. Unique identifier...

  10. Minimally Invasive Transcatheter Aortic Valve Replacement (TAVR)

    Medline Plus

    Full Text Available Watch a Broward Health surgeon perform a minimally invasive Transcatheter Aortic Valve Replacement (TAVR) Click Here to view the BroadcastMed, Inc. Privacy Policy and Legal Notice © 2017 BroadcastMed, Inc. ...

  11. Complete interruption of the aortic arch

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sung Hak; Park, In Kyu; Lee, Won Hwa; Kim, Yong Joo; Kang, Duk Sik; Lee, Jong Tae [Kyungpook National University College of Medicine, Taegu (Korea, Republic of)

    1984-09-15

    Complete interrupture of the aortic arch is one of the least common cardiac malformation. In this condition, continuity between the ascending and descending protions of the aorta is not present, and the descending aorta is supplied through a reversing patent ductus arteriosus. In the majority of the patients a ventricular septal defect is present. Authors have experienced a case of the complete interruption of aortic arch, interruption between the left carotid and the left subclavian artery.

  12. Effect of age on aortic atherosclerosis

    Institute of Scientific and Technical Information of China (English)

    Michael A. Chen; Miwa Kawakubo; Patrick M. Colletti; Dongxiang Xu; Laurie LaBree Dustin; Robert Detrano; Stanley P Azen; Nathan D. Wong; Xue-Qiao Zhao

    2013-01-01

    Objective To examine the association of atherosclerosis burden in the survivors of an asymptomatic elderly cohort study and its relationship to other coronary risk factors (specifically, age) by evaluating aortic atherosclerotic wall burden by magnetic resonance imaging (MRI). Methods A total of 312 participants in an ongoing observational cohort study underwent cardiac and descending thoracic aorta imaging by MRI. Maximum wall thickness was measured and the mean wall thickness calculated. Wall/outer wall ratio was used as a normalized wall index (NWI) adjusted for artery size difference among participants. Percent wall volume (PWV) was calculated as NWI × 100. Results In this asymptomatic cohort (mean age: 76 years), the mean (SD) aortic wall area and wall thickness were 222 ± 45 mm2 and 2.7 ± 0.4 mm, respectively. Maximum wall thickness was 3.4 ± 0.6 mm, and PWV was 32% ± 4%. Women appeared to have smaller wall area, but after correcting for their smaller artery size, had significantly higher PWV than men (P = 0.03). Older age was associated with larger wall area (P = 0.04 for trend) with similar PWVs. However, there were no statistically significant associations between standard risk factors, Framingham global risk, or metabolic syndrome status, therapy for cholesterol or hypertension, coronary or aortic calcium score, and the aortic wall burden. Aortic calcification was associated with coronary calcification. Conclusions Asymptomatic elderly in this cohort had a greater descending thoracic aortic wall volume that correlated with age, and women had a significantly increased PWV compared to men. In these survivors, the atherosclerotic aortic wall burden was not significantly associated with traditional risk factors or with coronary or aortic calcium scores or coronary calcium progression. Results suggest that age, or as yet unidentified risk factor(s), may be responsible for the increase in atherosclerosis.

  13. Aortic coarctation repair in the adult.

    Science.gov (United States)

    Cardoso, Goncalo; Abecasis, Miguel; Anjos, Rui; Marques, Marta; Koukoulis, Giovanna; Aguiar, Carlos; Neves, José Pedro

    2014-07-01

    Aortic coarctation can be repaired surgically or percutaneously. The decision should be made according to the anatomy and location of the coarctation, age of the patient, presence of other cardiac lesions, and other anatomic determinants (extensive collaterals or aortic calcification). This article reviews the different therapeutic options available, explaining the differences between children and adults, describing different approaches to the same disease, exemplified by three cases of nonclassic surgical approach and one percutaneous treatment.

  14. Aortic Dissection Cases Presenting with Neurological Deficit

    Directory of Open Access Journals (Sweden)

    Sibel Mumcu

    2014-06-01

    Full Text Available Aortic dissection can be fatal in case of underdiagnosis, and early treatment is essential for the survival. Although acute onset of chest or back pain is most common presenting symptoms, some patients might present with atypical findings such as acute stroke, mesenteric ischaemia, renal failure or myocardial infarction. Here, we report two cases presenting emergency room with atypical findings of aortic dissection which diagnosis is made during etiologic work up for ischemic stroke.

  15. Surveillance intervals for small abdominal aortic aneurysms

    DEFF Research Database (Denmark)

    Bown, Matthew J; Sweeting, Michael J; Brown, Louise C

    2013-01-01

    Small abdominal aortic aneurysms (AAAs [3.0 cm-5.4 cm in diameter]) are monitored by ultrasound surveillance. The intervals between surveillance scans should be chosen to detect an expanding aneurysm prior to rupture.......Small abdominal aortic aneurysms (AAAs [3.0 cm-5.4 cm in diameter]) are monitored by ultrasound surveillance. The intervals between surveillance scans should be chosen to detect an expanding aneurysm prior to rupture....

  16. Nonlinearities with Non-Gaussian Inputs.

    Science.gov (United States)

    1978-03-01

    possessing a spectral density function . a constant. Then Jet arc tan [G(t)J be the input. By Theorem 3 this input is not bandlimited; and if The rando...such that the absolute ,,~~ovalue of any point in the spectrum is less than N. If the Gaussian process X(t) possesses a H ~ ) spectral density function (i.e...Gaussian process and th. series ii convergent pointvise as veil X(t ) possesses a spectral density function . as in an sense (51. Let z~( ) and g2

  17. Input or intimacy

    Directory of Open Access Journals (Sweden)

    Judit Navracsics

    2014-01-01

    Full Text Available According to the critical period hypothesis, the earlier the acquisition of a second language starts, the better. Owing to the plasticity of the brain, up until a certain age a second language can be acquired successfully according to this view. Early second language learners are commonly said to have an advantage over later ones especially in phonetic/phonological acquisition. Native-like pronunciation is said to be most likely to be achieved by young learners. However, there is evidence of accentfree speech in second languages learnt after puberty as well. Occasionally, on the other hand, a nonnative accent may appear even in early second (or third language acquisition. Cross-linguistic influences are natural in multilingual development, and we would expect the dominant language to have an impact on the weaker one(s. The dominant language is usually the one that provides the largest amount of input for the child. But is it always the amount that counts? Perhaps sometimes other factors, such as emotions, ome into play? In this paper, data obtained from an EnglishPersian-Hungarian trilingual pair of siblings (under age 4 and 3 respectively is analyzed, with a special focus on cross-linguistic influences at the phonetic/phonological levels. It will be shown that beyond the amount of input there are more important factors that trigger interference in multilingual development.

  18. Impairment of flow-mediated dilation correlates with aortic dilation in patients with Marfan syndrome.

    Science.gov (United States)

    Takata, Munenori; Amiya, Eisuke; Watanabe, Masafumi; Omori, Kazuko; Imai, Yasushi; Fujita, Daishi; Nishimura, Hiroshi; Kato, Masayoshi; Morota, Tetsuro; Nawata, Kan; Ozeki, Atsuko; Watanabe, Aya; Kawarasaki, Shuichi; Hosoya, Yumiko; Nakao, Tomoko; Maemura, Koji; Nagai, Ryozo; Hirata, Yasunobu; Komuro, Issei

    2014-07-01

    Marfan syndrome is an inherited disorder characterized by genetic abnormality of microfibrillar connective tissue proteins. Endothelial dysfunction is thought to cause aortic dilation in subjects with a bicuspid aortic valve; however, the role of endothelial dysfunction and endothelial damaging factors has not been elucidated in Marfan syndrome. Flow-mediated dilation, a noninvasive measurement of endothelial function, was evaluated in 39 patients with Marfan syndrome. Aortic diameter was measured at the aortic annulus, aortic root at the sinus of Valsalva, sinotubular junction and ascending aorta by echocardiography, and adjusted for body surface area (BSA). The mean value of flow-mediated dilation was 6.5 ± 2.4 %. Flow-mediated dilation had a negative correlation with the diameter of the ascending thoracic aorta (AscAd)/BSA (R = -0.39, p = 0.020) and multivariate analysis revealed that flow-mediated dilation was an independent factor predicting AscAd/BSA, whereas other segments of the aorta had no association. Furthermore, Brinkman index had a somewhat greater influence on flow-mediated dilation (R = -0.42, p = 0.008). Although subjects who smoked tended to have a larger AscAd compared with non-smokers (AscA/BSA: 17.3 ± 1.8 versus 15.2 ± 3.0 mm/m(2), p = 0.013), there was no significant change in flow-mediated dilation, suggesting that smoking might affect aortic dilation via an independent pathway. Common atherogenic risks, such as impairment of flow-mediated dilation and smoking status, affected aortic dilation in subjects with Marfan syndrome.

  19. Estimation of central aortic pressure waveform features derived from the brachial cuff volume displacement waveform.

    Science.gov (United States)

    Butlin, Mark; Qasem, Ahmad; Avolio, Alberto P

    2012-01-01

    There is increasing interest in non-invasive estimation of central aortic waveform parameters in the clinical setting. However, controversy has arisen around radial tonometric based systems due to the requirement of a trained operator or lack of ease of use, especially in the clinical environment. A recently developed device utilizes a novel algorithm for brachial cuff based assessment of aortic pressure values and waveform (SphygmoCor XCEL, AtCor Medical). The cuff was inflated to 10 mmHg below an individual's diastolic blood pressure and the brachial volume displacement waveform recorded. The aortic waveform was derived using proprietary digital signal processing and transfer function applied to the recorded waveform. The aortic waveform was also estimated using a validated technique (radial tonometry based assessment, SphygmoCor, AtCor Medical). Measurements were taken in triplicate with each device in 30 people (17 female) aged 22 to 79 years of age. An average for each device for each individual was calculated, and the results from the two devices were compared using regression and Bland-Altman analysis. A high correlation was found between the devices for measures of aortic systolic (R(2)=0.99) and diastolic (R(2)=0.98) pressure. Augmentation index and subendocardial viability ratio both had a between device R(2) value of 0.82. The difference between devices for measured aortic systolic pressure was 0.5±1.8 mmHg, and for augmentation index, 1.8±7.0%. The brachial cuff based approach, with an individualized sub-diastolic cuff pressure, provides an operator independent method of assessing not only systolic pressure, but also aortic waveform features, comparable to existing validated tonometric-based methods.

  20. Elective reconstruction of thoracoabdominal aortic aneurysm type IV by transabdominal approach

    Directory of Open Access Journals (Sweden)

    Marjanović Ivan

    2012-01-01

    Full Text Available Introduction. Thoracoabdominal aortic aneurysm (TAAA type IV represents an aortic dilatation from the level of the diaphragmatic hiatus to the iliac arteries branches, including visceral branches of the aorta. In the traditional procedure of TAAA type IV repair, the body is opened using thoractomy and laparotomy in order to provide adequate exposure of the descending thoracic and abdominal aorta for safe aortic reconstruction. Case report. We reported a 71-yearold man with elective reconstruction of the TAAA type IV performed by transabdominal approach. Computed tomography scans angiography revealed a TAAA type IV with diameter of 62 mm in the region of celiac trunk and superior mesenteric artery branching, and the largest diameter of 75 mm in the infrarenal aortic level. The patient comorbidity included a chronic obstructive pulmonary disease and hypertension, therefore he was treated for a prolonged period. In preparation for the planned aortic reconstruction asymptomatic carotid disease (occlusion of the left internal carotid artery and subtotal stenosis of the right internal carotid artery was diagnosed. Within the same intervention percutaneous transluminal angioplasty with stent placement in right internal carotid artery was made. In general, under endotracheal anesthesia and epidural analgesia, with transabdominal approach performed aortic reconstruction with tubular dakron graft 24 mm were, and reimplantation of visceral aortic branches into the graft performed. Postoperative course was uneventful, and the patient was discharged on the postoperative day 17. Control computed tomography scan angiography performed three months after the operation showed vascular state of the patient to be in order. Conclusion. Complete transabdominal approach to TAAA type IV represents an appropriate substitute for thoracoabdominal approach, without compromising safety of the patient. This approach is less traumatic, especially in patients with impaired

  1. Aortic events in a nationwide Marfan syndrome cohort

    DEFF Research Database (Denmark)

    Groth, Kristian A; Krag, Kirstine Stochholm; Hove, Hanne;

    2016-01-01

    BACKGROUND: Marfan syndrome is associated with morbidity and mortality due to aortic dilatation and dissection. Preventive aortic root replacement has been the standard treatment in Marfan syndrome patients with aortic dilatation. In this study, we present aortic event data from a nationwide Marfan...... syndrome cohort. METHOD: The nationwide cohort of Danish Marfan syndrome patients was established from the Danish National Patient Registry and the Cause of Death Register, where we retrieved information about aortic surgery and dissections. We associated aortic events with age, sex, and Marfan syndrome...

  2. Transcatheter Aortic Valve Replacement With Early- and New-Generation Devices in Bicuspid Aortic Valve Stenosis

    DEFF Research Database (Denmark)

    Yoon, Sung-Han; Lefèvre, Thierry; Ahn, Jung-Ming

    2016-01-01

    BACKGROUND: Few studies have evaluated the clinical outcomes of transcatheter aortic valve replacement (TAVR) in patients with bicuspid aortic valve stenosis (AS). Particularly, limited data exist comparing the results of TAVR with new-generation devices versus early-generation devices. OBJECTIVE...

  3. Arterial elastance and heart-arterial coupling in aortic regurgitation are determined by aortic leak severity

    NARCIS (Netherlands)

    Segers, P; Morimont, P; Kolh, P; Stergiopulos, N; Westerhof, N; Verdonck, P

    2002-01-01

    Background In aortic valve regurgitation (AR), aortic leak severity modulates left ventricle (LV) arterial system interaction. The aim of this study was to assess (1) how arterial elastance (E-a), calculated as the ratio of LV end-systolic pressure and stroke volume, relates to arterial properties a

  4. Repositioning of an Intraventricular Dislocated Aortic Valve during Transcatheter Aortic Valve Implantation

    NARCIS (Netherlands)

    Natour, Ehsan; Douglas, Yvonne L.; Jainandunsing, Jayant S.; Schurer, Remco A. J.; van der Werf, Hendrik W.; van den Heuvel, Ad F. M.

    2014-01-01

    The case is presented of a 75-year-old man referred for transcatheter aortic valve implantation. During the procedure the prosthetic aortic valve became dislocated into the left ventricle shortly after expansion. The subsequent steps taken to reposition the valve using only materials at hand are des

  5. Effect of candesartan treatment on left ventricular remodeling after aortic valve replacement for aortic stenosis

    DEFF Research Database (Denmark)

    Dahl, Jordi S; Videbaek, Lars; Poulsen, Mikael K

    2010-01-01

    In hypertension, angiotensin receptor blockers can augment regression of left ventricular (LV) hypertrophy. It is not known whether this also is the case after aortic valve replacement (AVR) for severe aortic stenosis (AS). To test the hypothesis that treatment with candesartan in addition...

  6. Aortic annulus and ascending aorta: Comparison of preoperative and periooperative measurement in patients with aortic stenosis

    Energy Technology Data Exchange (ETDEWEB)

    Smid, Michal [Cardiology Department of Internal Medicine, School of Medicine Plzen, Charles University Prague and University Hospital Plzen, alej Svobody 80, 304 60 Plzen (Czech Republic)], E-mail: kosvin@seznam.cz; Ferda, Jiri [Department of Radiology, School of Medicine Plzen, Charles University Prague and University Hospital Plzen, alej Svobody 80, 304 60 Plzen (Czech Republic)], E-mail: ferda@fnplzen.cz; Baxa, Jan [Department of Radiology, School of Medicine Plzen, Charles University Prague and University Hospital Plzen, alej Svobody 80, 304 60 Plzen (Czech Republic)], E-mail: baxaj@fnplzen.cz; Cech, Jakub [Cardiology Department of Internal Medicine, School of Medicine Plzen, Charles University Prague and University Hospital Plzen, alej Svobody 80, 304 60 Plzen (Czech Republic)], E-mail: cechj@fnplzen.cz; Hajek, Tomas [Department of Cardiac Surgery, School of Medicine Plzen, Charles University Prague and University Hospital Plzen, alej Svobody 80, 304 60 Plzen (Czech Republic)], E-mail: hajekt@fnplzen.cz; Kreuzberg, Boris [Department of Radiology, School of Medicine Plzen, Charles University Prague and University Hospital Plzen, alej Svobody 80, 304 60 Plzen (Czech Republic)], E-mail: kreuzberg@fnplzen.cz; Rokyta, Richard [Cardiology Department of Internal Medicine, School of Medicine Plzen, Charles University Prague and University Hospital Plzen, alej Svobody 80, 304 60 Plzen (Czech Republic)], E-mail: rokyta@fnplzen.cz

    2010-04-15

    Background: Precise determination of the aortic annulus size constitutes an integral part of the preoperative evaluation prior to aortic valve replacement. It enables the estimation of the size of prosthesis to be implanted. Knowledge of the size of the ascending aorta is required in the preoperative analysis and monitoring of its dilation enables the precise timing of the operation. Our goal was to compare the precision of measurement of the aortic annulus and ascending aorta using magnetic resonance (MR), multidetector-row computed tomography (MDCT), transthoracic echocardiography (TTE), and transoesophageal echocardiography (TEE) in patients with degenerative aortic stenosis. Methods and results: A total of 15 patients scheduled to have aortic valve replacement were enrolled into this prospective study. TTE was performed in all patients and was supplemented with TEE, CT and MR in the majority of patients. The values obtained were compared with perioperative measurements. For the measurement of aortic annulus, MR was found to be the most precise technique, followed by MDCT, TTE, and TEE. For the measurement of ascending aorta, MR again was found to be the most precise technique, followed by MDCT, TEE, and TTE. Conclusion: In our study, magnetic resonance was found to be the most precise technique for the measurement of aortic annulus and ascending aorta in patients with severe degenerative aortic stenosis.

  7. General Considerations of Ruptured Abdominal Aortic Aneurysm: Ruptured Abdominal Aortic Aneurysm

    OpenAIRE

    Lee, Chung Won; Bae, Miju; Chung, Sung Woon

    2015-01-01

    Although development of surgical technique and critical care, ruptured abdominal aortic aneurysm still carries a high mortality. In order to obtain good results, various efforts have been attempted. This paper reviews initial management of ruptured abdominal aortic aneurysm and discuss the key point open surgical repair and endovascular aneurysm repair.

  8. Access to Research Inputs

    DEFF Research Database (Denmark)

    Czarnitzki, Dirk; Grimpe, Christoph; Pellens, Maikel

    The viability of modern open science norms and practices depend on public disclosure of new knowledge, methods, and materials. However, increasing industry funding of research can restrict the dissemination of results and materials. We show, through a survey sample of 837 German scientists in life...... sciences, natural sciences, engineering, and social sciences, that scientists who receive industry funding are twice as likely to deny requests for research inputs as those who do not. Receiving external funding in general does not affect denying others access. Scientists who receive external funding...... of any kind are, however, 50% more likely to be denied access to research materials by others, but this is not affected by being funded specifically by industry....

  9. Access to Research Inputs

    DEFF Research Database (Denmark)

    Czarnitzki, Dirk; Grimpe, Christoph; Pellens, Maikel

    2015-01-01

    The viability of modern open science norms and practices depends on public disclosure of new knowledge, methods, and materials. However, increasing industry funding of research can restrict the dissemination of results and materials. We show, through a survey sample of 837 German scientists in life...... sciences, natural sciences, engineering, and social sciences, that scientists who receive industry funding are twice as likely to deny requests for research inputs as those who do not. Receiving external funding in general does not affect denying others access. Scientists who receive external funding...... of any kind are, however, 50 % more likely to be denied access to research materials by others, but this is not affected by being funded specifically by industry...

  10. On the Nature of the Input in Optimality Theory

    DEFF Research Database (Denmark)

    Heck, Fabian; Müller, Gereon; Vogel, Ralf;

    2002-01-01

    The input has two main functions in optimality theory (Prince and Smolensky 1993). First, the input defines the candidate set, in other words it determines which output candidates compete for optimality, and which do not. Second, the input is referred to by faithfulness constraints that prohibit...

  11. Aortenklappeninsuffizienz – Operationsindikationen und Möglichkeiten der Aortenklappenrekonstruktion // Aortic Regurgitation – Aortic Valve Repair

    Directory of Open Access Journals (Sweden)

    Schachner T

    2015-01-01

    Full Text Available Aortic valve repair for aortic regurgitation has evolved at dedicated centres. It is a valuable alternative to aortic valve replacement and offers good long term results. Tricuspid, as well as bicuspid aortic valves, are suitable for repair. These techniques of aortic valve repair can be combined with reconstruction of concomitant aneurysmal disease of the ascending aorta or the sinus valsalvae. In particular, younger patients can benefit from a life without oral anticoagulation. p bKurzfassung: /bDie Aortenklappenrekonstruktion bei bestehender Aortenklappeninsuffizienz hat sich in spezialisierten Zentren zu einer guten Behandlungsalternative zum Aortenklappenersatz entwickelt. Es können sowohl bikuspide als auch trikuspide Aortenklappen rekonstruiert werden. Bei Vorliegen eines Aortenaneurysmas können Techniken der Aortenklappenrekonstruktion mit dem Ersatz von Aorta ascendens oder Sinus valsalvae kombiniert werden. In spezialisierten Zentren können gute Langzeitergebnisse erzielt werden, die vor allem jüngeren Patienten ein Leben ohne orale Antikoagulation ermöglichen.

  12. Combined surgical and catheter-based treatment of extensive thoracic aortic aneurysm and aortic valve stenosis

    DEFF Research Database (Denmark)

    De Backer, Ole; Lönn, Lars; Søndergaard, Lars

    2015-01-01

    endovascular aneurysm repair (TEVAR) has changed and extended management options in thoracic aorta disease, including in those patients deemed unfit or unsuitable for open surgery. Accordingly, transcatheter aortic valve replacement (TAVR) is increasingly used to treat patients with symptomatic severe aortic...... valve stenosis (AS) who are considered at high risk for surgical aortic valve replacement. In this report, we describe the combined surgical and catheter-based treatment of an extensive TAA and AS. To our knowledge, this is the first report of hybrid TAA repair combined with TAVR.......An extensive thoracic aortic aneurysm (TAA) is a potentially life-threatening condition and remains a technical challenge to surgeons. Over the past decade, repair of aortic arch aneurysms has been accomplished using both hybrid (open and endovascular) and totally endovascular techniques. Thoracic...

  13. Aortic root, not valve, calcification correlates with coronary artery calcification in patients with severe aortic stenosis

    DEFF Research Database (Denmark)

    Henein, Michael; Hällgren, Peter; Holmgren, Anders

    2015-01-01

    BACKGROUND: The underlying pathology in aortic stenosis (AS) and coronary artery stenosis (CAS) is similar including atherosclerosis and calcification. We hypothesize that coronary artery calcification (CAC) is likely to correlate with aortic root calcification (ARC) rather than with aortic valve...... calcification (AVC), due to tissue similarity between the two types of vessel rather than with the valve leaflet tissue. MATERIAL AND METHODS: We studied 212 consecutive patients (age 72.5 ± 7.9 years, 91 females) with AS requiring aortic valve replacement (AVR) in two Heart Centers, who underwent multidetector...... cardiac CT preoperatively. CAC, AVC and ARC were quantified using Agatston scoring. Correlations were tested by Spearman's test and Mann-Whitney U-test was used for comparing different subgroups; bicuspid (BAV) vs tricuspid (TAV) aortic valve. RESULTS: CAC was present in 92%, AVC in 100% and ARC in 82...

  14. Patch annulo-aortoplasty in an adult patient with congenital supravalvular aortic stenosis and a small aortic annulus.

    Science.gov (United States)

    Morimoto, Naoto; Morimoto, Keisuke; Morimoto, Yoshihisa; Tanaka, Akiko; Sakamoto, Toshihito; Okada, Kenji; Okita, Yutaka

    2011-08-01

    A 39-year-old woman with familial homozygous hypercholesterolemia had supravalvular and valvular aortic stenosis. Modified Nick's procedure and aortic valve replacement was performed to relieve both the supravalvular and annular stenoses. At surgery, the ascending aorta was found to be narrowing at the level of the sinotubular junction, which was compatible with congenital supravalvular aortic stenosis. Histological examination of the aortic cusps showed sclerotic change due to hypercholesterolemia. These findings indicated that familial homozygous hypercholesterolemia caused valvular aortic stenosis and exacerbated congenital supravalvular aortic stenosis.

  15. Incidental moderate mitral regurgitation in patients undergoing aortic valve replacement for aortic stenosis: review of guidelines and current evidence.

    Science.gov (United States)

    Ramakrishna, Harish; Kohl, Benjamin A; Jassar, Arminder S; Augoustides, John G T

    2014-04-01

    Recent evidence has shown that moderate mitral regurgitation is common and clinically relevant in patients presenting for surgical and transcatheter aortic valve replacement for aortic stenosis. Prospective multicenter clinical trials are now indicated to resolve the clinical equipoise about whether or not mitral valve intervention also is indicated at the time of aortic valve intervention. Advances in three-dimensional transesophageal echocardiography, transcatheter mitral interventions, and surgical aortic valve replacement, including the advent of sutureless valves, likely will expand the therapeutic possibilities for moderate mitral regurgitation in the setting of aortic valve interventions for severe aortic stenosis.

  16. Measurement and determinants of infrarenal aortic thrombus volume

    Energy Technology Data Exchange (ETDEWEB)

    Golledge, Jonathan; Wolanski, Philippe [James Cook University, The Vascular Biology Unit, Townsville, Queensland (Australia); Townsville Hospital, Townsville, Queensland (Australia); Parr, Adam [James Cook University, The Vascular Biology Unit, Townsville, Queensland (Australia); Buttner, Petra [James Cook University, School of Public Health and Tropical Medicine, Townsville, Queensland (Australia)

    2008-09-15

    Intra-luminal thrombus has been suggested to play a role in the progression of abdominal aortic aneurysm (AAA). The aims of this study were twofold. Firstly, to assess the reproducibility of a computer tomography (CT)-based technique for measurement of aortic thrombus volume. Secondly, to examine the determinants of infrarenal aortic thrombus volume in a cohort of patients with aortic dilatation. A consecutive series of 75 patients assessed by CT angiography with maximum aortic diameter {>=}25 mm were recruited. Intra-luminal thrombus volume was measured by a semi-automated workstation protocol based on a previously defined technique to quantitate aortic calcification. Intra- and inter-observer reproducibility were assessed using correlation coefficients, coefficient of variation and Bland-Altman plots. Infrarenal aortic thrombus volume percentage was related to clinical, anatomical and blood characteristics of the patients using univariate and multivariate tests. Infrarenal aortic thrombus volume was related to the severity of aortic dilatation assessed by total aortic volume (r=0.87, P<0.0001) or maximum aortic diameter (r=0.74, P< 0.0001). We therefore examined the clinical determinates of aortic thrombus expressed as a percentage of total aortic volume. Aortic thrombus percentage was negatively correlated with serum high density lipoprotein (HDL, r=-0.31). By ordinal multiple logistic regression analysis serum HDL below median ({<=}1.2 mM) was associated with aortic thrombus percentage in the upper quartile adjusting for other risk factors (odds ratio 5.3, 95% CI 1.1-25.0). Infrarenal aortic thrombus volume can be measured reproducibly on CT. Serum HDL, which can be therapeutically raised, may play a role in discouraging aortic thrombus accumulation with implications in terms of delaying progression of AAA. (orig.)

  17. Aneurismas da aorta Aortic aneurysms

    Directory of Open Access Journals (Sweden)

    Januário M Souza

    1992-09-01

    Full Text Available Entre janeiro de 1979 e janeiro de 1992, foram realizadas 212 operações para correção de aneurismas e de dissecções da aorta. Neste trabalho serão analisados 104 procedimentos cirúrgicos (em 97 pacientes para correção de aneurismas. A idade dos pacientes variou de 14 a 79 anos (média 59,5 anos e o sexo predominante foi o masculino, com 75 pacientes. Os aneurismas localizavam-se na aorta ascendente em 46 pacientes, na croça em 8, na aorta descendente em 8, na aorta toráco-abdominal em 8, na aorta abdominal em 21, na aorta descendente e abdominal em 2, na aorta ascendente e tóraco-abdominal em 2, na aorta ascendente e descendente em 1, na aorta ascendente, croça e descendente em 1. Doenças cardiovasculares associadas estavam presentes em 39 pacientes, sendo valvopatia aórtica em 18 (excluídos os pacientes com ectasiaânulo-aórtíca, insuficiência coronária em 17, coarctação da aorta em 2, persistência do canal arterial em 1 e valvopatia mitral e aórtica em 1. A mortalidade imediata (hospitalar e/ou 30 dias foi de 14,4%, sendo de 27,7% (5/18 para pacientes com mais de 70 anos e de 11,3% (9/79 para pacientes com idade inferior a 70 anos. Os aneurismas localizados na aorta ascendente e croça foram operados como o auxílio de circulação extracorpórea. Parada circulatória e hipotermia profunda foram utilizadas em todos os pacientes com aneurisma da croça. O estudo tomográfico e angiográfico deve ser de toda a aorta, pela possibilidade de aneurismas de localizações múltiplas.Among 212 patients undergoing operation for aortic aneurysm and aortic dissection between January 1979 and January 1992, 97 were operated on for aneurysms. The aneurysms were localized in: ascending aorta in 46 patients, transverse aortic arch in 8, descending aorta in 8, thoracoabdominal aorta in 8, abdominal (infrarenal aorta in 21, descending and abdominal aorta in 2, ascending and thoracoabdominal aorta in 2, ascending and descending in 1

  18. Dynamic finite element analysis of the aortic root from MRI-derived parameters.

    Science.gov (United States)

    Conti, Carlo A; Votta, Emiliano; Della Corte, Alessandro; Del Viscovo, Luca; Bancone, Ciro; Cotrufo, Maurizio; Redaelli, Alberto

    2010-03-01

    An understanding of aortic root biomechanics is pivotal for the optimisation of surgical procedures aimed at restoring normal root function in pathological subjects. For this purpose, computational models can provide important information, as long as they realistically capture the main anatomical and functional features of the aortic root. Here we present a novel and realistic finite element (FE) model of the physiological aortic root, which simulates its function during the entire cardiac cycle. Its geometry is based on magnetic resonance imaging (MRI) data obtained from 10 healthy subjects and accounts for the geometrical differences between the leaflet-sinus units. Morphological realism is combined with the modelling of the leaflets' non-linear and anisotropic mechanical response, in conjunction with dynamic boundary conditions. The results show that anatomical differences between leaflet-sinus units cause differences in stress and strain patterns. These are notably higher for the leaflets and smaller for the sinuses. For the maximum transvalvular pressure value, maximum principal stresses on the leaflets are equal to 759, 613 and 603 kPa on the non-coronary, right and left leaflet, respectively. For the maximum aortic pressure, average maximum principal stresses values are equal to 118, 112 and 111 kPa on the right, non-coronary and left sinus, respectively. Although liable of further improvements, the model seems to reliably reproduce the behaviour of the real aortic root: the model's leaflet stretches, leaflet coaptation lengths and commissure motions, as well as the timings of aortic leaflet closures and openings, all matched with the experimental findings reported in the literature.

  19. The clinical application of multi-slice spiral CT angiography in abdominal aortic disease

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Objective: To evaluate the clinical application of multi-slice spiral CT angiography(MSCTA) in the assessment of abdominal aortic disease. Methods: Fifty-four patients underwent multi-slice spiral CT angiography of abdomen. Contrast agent (Omnipaque 300 I g/L) 1.5 ml/kg was injected and the injection rate was 3 ml/s. The delay time was determined by bolus tracking technique,Tll level abdominal aorta was set as the target vessel and the threshold was 180-200 Hu, slice width was 3 mm and with a pitch of 4-6.Original data were transferred to working-station to perform functional reconstruction. Results: Ten cases were normal, twenty-eight cases were abdominal aortic aneurysms, five abdominal aortic dissecting aneurysms (Debakay type Ⅲ ) and eleven aortic sclerosis. SSD showed the body of aneurysm and the relationship between aneurysm and adjacent blood vessel, MIP better displayed calcification of blood vessel wall and condition of the stent, MPR demonstrated true and false lumen, rupture site of abdominal aorta intima and mural thrombus. Conclusion: MSCTA axial and reconstruction image can show the extent of abdominal aortic disease and the relationship with adjacent blood vessels. It is a safe, simple and non-invasive examination method.

  20. Vasopressor mechanisms in acute aortic coarctation hypertension

    Directory of Open Access Journals (Sweden)

    Salgado H.C.

    1997-01-01

    Full Text Available Angiotensin II (ANG II and vasopressin (AVP act together with the mechanical effect of aortic constriction in the onset of acute aortic coarctation hypertension. Blockade of ANG II and AVP V1 receptors demonstrated that ANG II acts on the prompt (5 min rise in pressure whereas AVP is responsible for the maintenance (30-45 min of the arterial pressure elevation during aortic coarctation. Hormone assays carried out on blood collected from conscious rats submitted to aortic constriction supported a role for ANG II in the early stage and a combined role for both ANG II and AVP in the maintenance of proximal hypertension. As expected, a role for catecholamines was ruled out in this model of hypertension, presumably due to the inhibitory effect of the sinoaortic baroreceptors. The lack of afferent feedback from the kidneys for AVP release from the central nervous system in rats with previous renal denervation allowed ANG II to play the major role in the onset of the hypertensive response. Median eminence-lesioned rats exhibited a prompt increase in proximal pressure followed by a progressive decline to lower hypertensive levels, revealing a significant role for the integrity of the neuroaxis in the maintenance of the aortic coarctation hypertension through the release of AVP. In conclusion, the important issue raised by this model of hypertension is the likelihood of a link between some vascular territory - probably renal - below the coarctation triggering the release of AVP, with this vasoconstrictor hormone participating with Ang II and the mechanical effect of aortic constriction in the acute aortic coarctation hypertension

  1. Atherosclerotic Aortic Plaques Detected by Transesophageal Echocardiography

    Institute of Scientific and Technical Information of China (English)

    赵云; 朱文玲; 倪超; 郭丽琳; 曾勇; 方理刚

    2002-01-01

    Objective To evaluate the predictive value of atherosclerotic aortic plaques in coronary artery disease (CAD) Methods In 50patients with suspected coronary artery disease, transesophageal echocardiography was performed to examine their thoracic aortas 2 weeks before or after coronary angiography. In the cases of coronary angiography studied, stenosis of the coronary artery ≥ 50 % was considered to be due to coronary artery disease,whereas the thickness of the intima ≥ 1.3 mm was taken to be the criteria for the presence of an atherosclerotic aortic plaque on the transesophageal echocardiographic test. Results Among the 50 patients, 37 cases were diagnosed as CAD and 13 cases were considered to be normal. The plaques of the thoracic aorta were observed in 34cases in the CAD group and 3 cases in the normal group. The sensitivity and specificity of aortic plaques for CAD were 91.9 % and 76.9%, respectively. The positive and negative predictive values of the aortic plaques for CAD were 91.9% and 76.9%, respectively. The accuracy was 88.0%. 80 percent of the patients with single- yes sel disease had thoracic aortic plaques, 92 percent of the patients with two-vessel disease and 100 percent of the patients with three-vessel disease had thoracic aortic plaques. There was a significant difference in the thickness of aortic intimas between the normal group and the CAD group. Conclusions Detectingatherosclerotic plaques in the thoracic aorta with transesophageal echocardiography may be of great value in predicting the presence and extent of coronary artery disease.

  2. Transcatheter aortic valve implantation in failed bioprosthetic surgical valves

    DEFF Research Database (Denmark)

    Dvir, Danny; Webb, John G; Bleiziffer, Sabine

    2014-01-01

    IMPORTANCE: Owing to a considerable shift toward bioprosthesis implantation rather than mechanical valves, it is expected that patients will increasingly present with degenerated bioprostheses in the next few years. Transcatheter aortic valve-in-valve implantation is a less invasive approach......, stroke, and New York Heart Association functional class. RESULTS: Modes of bioprosthesis failure were stenosis (n = 181 [39.4%]), regurgitation (n = 139 [30.3%]), and combined (n = 139 [30.3%]). The stenosis group had a higher percentage of small valves (37% vs 20.9% and 26.6% in the regurgitation...

  3. [New technique of concomitant replacement of the aortic valve and the ascending aorta with enlargement of the aortic annulus for congenital bicuspid aortic valve].

    Science.gov (United States)

    Takahara, Shingo; Fukasawa, Manabu; Kawahara, Yu; Suzuki, Kotaro; Kobayashi, Yuriko

    2012-12-01

    Congenital bicuspid aortic valve (BAV) is one of the most common congenital heart diseases, with a high incidence of associated valvular lesions and aortic abnormalities including aortic stenosis( AS), aortic regurgitation, aortic dilatation, and aortic dissection. Patients with BAV and AS often have a small aortic annulus. We encountered a case of BAV in which a 51-year-old woman with severe AS having a small aortic annulus and a dilated ascending aorta required surgical intervention. We performed the surgery using new technique that involved concomitant replacement of the aortic valve and the ascending aorta with enlargement of the aortic annulus using a single uniquely-shaped graft to avoid prosthesis patient mismatch. We trimmed the proximal end of the straight graft in shape of 2 teardrops hanging on it to fit the cut annulus. It requires only a single suture line to replace the ascending aorta and enlarge the aortic annulus, which entails a decreased risk of bleeding during surgery. We believe that it could be applicable to many cases requiring concomitant surgery.

  4. Mutations in smooth muscle alpha-actin (ACTA2) lead to thoracic aortic aneurysms and dissections.

    Science.gov (United States)

    Guo, Dong-Chuan; Pannu, Hariyadarshi; Tran-Fadulu, Van; Papke, Christina L; Yu, Robert K; Avidan, Nili; Bourgeois, Scott; Estrera, Anthony L; Safi, Hazim J; Sparks, Elizabeth; Amor, David; Ades, Lesley; McConnell, Vivienne; Willoughby, Colin E; Abuelo, Dianne; Willing, Marcia; Lewis, Richard A; Kim, Dong H; Scherer, Steve; Tung, Poyee P; Ahn, Chul; Buja, L Maximilian; Raman, C S; Shete, Sanjay S; Milewicz, Dianna M

    2007-12-01

    The major function of vascular smooth muscle cells (SMCs) is contraction to regulate blood pressure and flow. SMC contractile force requires cyclic interactions between SMC alpha-actin (encoded by ACTA2) and the beta-myosin heavy chain (encoded by MYH11). Here we show that missense mutations in ACTA2 are responsible for 14% of inherited ascending thoracic aortic aneurysms and dissections (TAAD). Structural analyses and immunofluorescence of actin filaments in SMCs derived from individuals heterozygous for ACTA2 mutations illustrate that these mutations interfere with actin filament assembly and are predicted to decrease SMC contraction. Aortic tissues from affected individuals showed aortic medial degeneration, focal areas of medial SMC hyperplasia and disarray, and stenotic arteries in the vasa vasorum due to medial SMC proliferation. These data, along with the previously reported MYH11 mutations causing familial TAAD, indicate the importance of SMC contraction in maintaining the structural integrity of the ascending aorta.

  5. The Potential Role of Kallistatin in the Development of Abdominal Aortic Aneurysm.

    Science.gov (United States)

    Li, Jiaze; Krishna, Smriti Murali; Golledge, Jonathan

    2016-08-11

    Abdominal aortic aneurysm (AAA) is a vascular condition that causes permanent dilation of the abdominal aorta, which can lead to death due to aortic rupture. The only treatment for AAA is surgical repair, and there is no current drug treatment for AAA. Aortic inflammation, vascular smooth muscle cell apoptosis, angiogenesis, oxidative stress and vascular remodeling are implicated in AAA pathogenesis. Kallistatin is a serine proteinase inhibitor, which has been shown to have a variety of functions, potentially relevant in AAA pathogenesis. Kallistatin has been reported to have inhibitory effects on tumor necrosis factor alpha (TNF-α) signaling induced oxidative stress and apoptosis. Kallistatin also inhibits vascular endothelial growth factor (VEGF) and Wnt canonical signaling, which promote inflammation, angiogenesis, and vascular remodeling in various pre-clinical experimental models. This review explores the potential protective role of kallistatin in AAA pathogenesis.

  6. The Potential Role of Kallistatin in the Development of Abdominal Aortic Aneurysm

    Directory of Open Access Journals (Sweden)

    Jiaze Li

    2016-08-01

    Full Text Available Abdominal aortic aneurysm (AAA is a vascular condition that causes permanent dilation of the abdominal aorta, which can lead to death due to aortic rupture. The only treatment for AAA is surgical repair, and there is no current drug treatment for AAA. Aortic inflammation, vascular smooth muscle cell apoptosis, angiogenesis, oxidative stress and vascular remodeling are implicated in AAA pathogenesis. Kallistatin is a serine proteinase inhibitor, which has been shown to have a variety of functions, potentially relevant in AAA pathogenesis. Kallistatin has been reported to have inhibitory effects on tumor necrosis factor alpha (TNF-α signaling induced oxidative stress and apoptosis. Kallistatin also inhibits vascular endothelial growth factor (VEGF and Wnt canonical signaling, which promote inflammation, angiogenesis, and vascular remodeling in various pre-clinical experimental models. This review explores the potential protective role of kallistatin in AAA pathogenesis.

  7. MicroRNAs, fibrotic remodeling, and aortic aneurysms

    Science.gov (United States)

    Milewicz, Dianna M.

    2012-01-01

    Aortic aneurysms are a common clinical condition that can cause death due to aortic dissection or rupture. The association between aortic aneurysm pathogenesis and altered TGF-β signaling has been the subject of numerous investigations. Recently, a TGF-β–responsive microRNA (miR), miR-29, has been identified to play a role in cellular phenotypic modulation during aortic development and aging. In this issue of JCI, Maegdefessel and colleagues demonstrate that decreasing the levels of miR-29b in the aortic wall can attenuate aortic aneurysm progression in two different mouse models of abdominal aortic aneurysms. This study highlights the relevance of miR-29b in aortic disease but also raises questions about its specific role. PMID:22269322

  8. Notch signaling in descending thoracic aortic aneurysm and dissection

    NARCIS (Netherlands)

    Zou, S.; Ren, P.; Nguyen, M.; Coselli, J.S.; Shen, Y.H.; Lemaire, S.A.

    2012-01-01

    BACKGROUND: Descending thoracic aortic aneurysm and dissection (DTAAD) is characterized by progressive medial degeneration, which may result from excessive tissue destruction and insufficient repair. Resistance to tissue destruction and aortic self-repair are critical in preventing medial degenerati

  9. Controlling methods of a newly developed extra aortic counter-pulsation device using shape memory alloy fibers.

    Science.gov (United States)

    Hashem, Mohamed O; Yamada, A; Tsuboko, Y; Muira, H; Homma, D; Shiraishi, Y; Yambe, T

    2013-01-01

    Diastolic counter-pulsation has been used to provide circulatory augmentation for short term cardiac support. The success of intra-aortic balloon pump (IABP) therapy has generated interest in long term counter-pulsation strategies to treat heart failure patients. The authors have been developing a totally implantable extra aortic pulsation device for the circulatory support of heart failure patients, using 150 µm Ni-Ti anisotropic shape memory alloy (SMA) fibers. These fibers contract by Joule heating with an electric current supply. The special features of our design are as follow: non blood contacting, extra aortic pulsation function synchronizing with the native heart, a wrapping mechanical structure for the aorta in order to achieve its assistance as the aortomyoplsty and the extra aortic balloon pump. The device consisted of rubber silicone wall plates, serially connected for radial contraction. We examined the contractile function of the device, as well as it controlling methods; the phase delay parameter and the pulse width modulation, in a systemic mock circulatory system, with a pneumatically driven silicone left ventricle model, arterial rubber tubing, a peripheral resistance unit, and a venous reservoir. The device was secured around the aortic tubing with a counter-pulsation mode of 1:4 against the heartbeat. Pressure and flow waveforms were measured at the aortic outflow, as well as its driving condition of the contraction phase width and the phase delay. The device achieved its variable phase control for co-pulsation or counter-pulsation modes by changing the phase delay of the SMA fibers. Peak diastolic pressure significantly augmented, mean flow increased (p<0.05) according to the pulse width modulation. Therefore the newly developed extra aortic counter-pulsation device using SMA fibers, through it controlling methods indicated its promising alternative extra aortic approach for non-blood contacting cardiovascular circulatory support.

  10. Rapid prototyping in aortic surgery.

    Science.gov (United States)

    Bangeas, Petros; Voulalas, Grigorios; Ktenidis, Kiriakos

    2016-04-01

    3D printing provides the sequential addition of material layers and, thus, the opportunity to print parts and components made of different materials with variable mechanical and physical properties. It helps us create 3D anatomical models for the better planning of surgical procedures when needed, since it can reveal any complex anatomical feature. Images of abdominal aortic aneurysms received by computed tomographic angiography were converted into 3D images using a Google SketchUp free software and saved in stereolithography format. Using a 3D printer (Makerbot), a model made of polylactic acid material (thermoplastic filament) was printed. A 3D model of an abdominal aorta aneurysm was created in 138 min, while the model was a precise copy of the aorta visualized in the computed tomographic images. The total cost (including the initial cost of the printer) reached 1303.00 euros. 3D imaging and modelling using different materials can be very useful in cases when anatomical difficulties are recognized through the computed tomographic images and a tactile approach is demanded preoperatively. In this way, major complications during abdominal aorta aneurysm management can be predicted and prevented. Furthermore, the model can be used as a mould; the development of new, more biocompatible, less antigenic and individualized can become a challenge in the future.

  11. Flow in an Aortic Coarctation

    Science.gov (United States)

    Loma, Luis; Miller, Paul; Hertzberg, Jean

    2009-11-01

    Coarctation of the aorta is a congenital cardiovascular defect that causes a constriction in the descending thoracic aorta. To gain a better understanding of the cause of post-surgical problems, a rigid glass and a compliant in vitro model of the aortic arch and descending aorta with a coarctation were constructed. Near-physiologic compliance was obtained using a silicone elastomer. Stereoscopic PIV was used to obtain 3D velocity maps. Results show a high speed turbulent jet formed at the exit of the coarctation. Flow in the rigid model was significantly different from in the compliant model. In the rigid model, the jet was symmetric, creating a toroidal recirculation area. In the compliant model, the jet was directed towards the medial wall, inducing flow reversal only at the lateral wall. Peak velocities and turbulence intensities were higher in the rigid model, however shear rate values in the compliant model were significantly above both the rigid model and normal in vivo values at the medial wall. In both models the reattachment region fluctuated, creating oscillatory shear.

  12. A Clinicopathological Study on Aortic Valves in Children

    Institute of Scientific and Technical Information of China (English)

    HUANG Ping; WANG Hongwei; ZHANG Zhenlu; HU Xiufen; LI Yanping; CHENG Peixuan; LIU Jianying

    2007-01-01

    In order to investigate the clinicopathological characteristics of aortic valve disease in children, all the native surgically excised aortic valves obtained between January 2003 and December 2005 were studied macroscopically and microscopically. The patients' medical records were reviewed and the clinical information was extracted. According to preoperative echocardiography, intraoperative assessment, and postoperative pathology, combined with clinical symptoms and signs, aortic valve diseases were divided into three categories: aortic stenosis (AS), aortic insufficiency (AI), and aortic stenosis with insufficiency (AS-AI). The etiology was determined according to the macroscopic, microscopic and clinical findings. The results showed that among 70 aortic valves, patient age ranged from 6 to 18 years, with a mean of 15.4 years, and there were 56 boys and 14 girts (male: female=4:1). Forty-four children only had pure aortic valve disease, and the other 26 children had aortic valve disease associated with other heart valve diseases. There were 5 cases of AS (7.14%), 60 cases of AI (85.71%) and 5 cases of AS-AI (7.14%). The causes were congenital aortic valve malformation (32 cases, 45.71%), rheumatic disease (28 cases, 40%), infective endocarditis (7 cases,10%), Marfan syndrome (2 cases, 2.86%), and undetermined (1 case, 1.43%). It was concluded that the common causes of aortic valve disease in order of frequency in children were congenital aortic valve malformation, rheumatic disease, infective endocarditis, and Marfan syndrome. AI was more common in children with aortic valve disease. Compared with adult patients, congenital bicuspid aortic valve in children was often AI. Histologically, the leaflets of congenital bicuspid aortic valve were mainly myxomatous, fibrosis and calcification less seen. AI was frequently found in rheumatic disease, mostly associated with other heart valve diseases. Macroscopic and microscopic examinations together with clinical

  13. A Neural Network for Estimation of Aortic Pressure from the Radial Artery Pressure Pulse

    Science.gov (United States)

    2001-10-25

    from periphery to artery: a model based study, American Journal of Physiology, 1998,274:43, pp H1386-92 [9] C. Chen, E. Nevo , B Fetics, P Pak, F, Yin, L...36. [10] B Fetics, E Nevo , C. Chen, D Kass, Parametric model derivation of transfer function for noninvasive estimation of aortic pressure by radial

  14. Is there alteration in aortic stiffness in Leber hereditary optic neuropathy?

    NARCIS (Netherlands)

    Nemes, A.; Coo, I.F.M. de; Spruijt, L.; Smeets, H.J.; Chinnery, P.F.; Soliman, O.I.; Geleijnse, M.L.; Cate, FJ Ten

    2008-01-01

    PURPOSE: Leber hereditary optic neuropathy (LHON) is recognized as the most common cause of isolated blindness in young men. The current study was designed to test whether LHON as a mitochondrial disease is associated with vascular functional alterations characterized by aortic elastic properties du

  15. Myocardial infarction with aortic banding - A combined rat model of heart failure

    NARCIS (Netherlands)

    Anthonio, RL; vanVeldhuisen, DJ; vanBekkum, C; deBoer, E; vanGilst, WH

    1997-01-01

    The effect of additional abdominal aortic banding on parameters of heart failure was studied in male Wistar rats with myocardial infarction. Contractile function was studied 8-9 weeks after operation, with an isoprenaline dose response protocol, in a retrograde Langendorff perfusion. Also, plasma no

  16. Transcatheter aortic valve implantation: status and challenges.

    Science.gov (United States)

    Fishbein, Gregory A; Schoen, Frederick J; Fishbein, Michael C

    2014-01-01

    Calcific aortic valve disease of the elderly is the most prevalent hemodynamically-significant valvular disease, and the most common lesion requiring valve replacement in industrialized countries. Transcatheter aortic valve implantation is a less invasive alternative to classical aortic valve replacement that can provide a therapeutic option for high-risk or inoperable patients with aortic stenosis. These devices must be biocompatible, have excellent hemodynamic performance, be easy to insert, be securely anchored without sutures, and be durable, without increased risk of thrombosis or infection. To date, complications are related to the site of entry for insertion, the site of implantation (aorta, coronary ostia, base of left ventricle), and to the structure and design of the inserted device. However, as with any novel technology unanticipated complications will develop. Goals for future development will be to make the devices more effective, more durable, safer, and easier to implant, so as to further improve outcome for patients with severe aortic stenosis. The pathologist participating in research and development, and examination of excised devices will have a critical role in improving outcome for these patients.

  17. The Early Variation of Left Ventricular Strain after Aortic Valve Replacement by Three-Dimensional Echocardiography.

    Directory of Open Access Journals (Sweden)

    Yongle Chen

    Full Text Available Aortic stenosis (AS and aortic incompetence (AI are common aortic valve diseases. Both may deteriorate into irreversible myocardial dysfunction and will increase the risk of sudden death. In this study, we aimed to investigate the early variation trend of left ventricular function by three-dimensional speckle tracking echocardiography (3D-STE in the patients who underwent cardiac surgeries for aortic valve disease. Twenty patients with severe aortic AS and 16 patients with severe AI were enrolled. All of them underwent the aortic valve replacement (AVR procedures. The patients' global longitudinal strain (GLS and global circumferential strain (GCS were evaluated by 3D-STE before surgery and at 1 week after surgery. In addition, GLS and GCS were followed at 1 month as well as 3 months after AVR. In AS patients, the GCS after AVR altered little both at 1 week (p = 0.562 and at 1 month (p = 0.953 compared with the data before the surgery. And it increased significantly at 3 months of follow-up observation compared to that before AVR (p<0.05. Meanwhile, GLS increased progressively after AVR and improved significantly at 3 months after surgery (p<0.05. For the AI patients, GLS as well as GCS decreased at 1 week after AVR compared to those data at baseline (p<0.05. However, these two parameters recovered at 1 month after AVR. Furthermore, GLS and GCS improved significantly at 3 months after the surgery (p<0.05. Therefore, both GLS and GCS were influenced by AVR and would be improved at 3 months after surgery both in AS patients or AI patients. GLS and GCS can be finely evaluated by 3D-STE, and they are helpful to determine the variation tendency of left ventricular function in patients with AVR.

  18. Fenestrated endovascular aortic repair for juxtarenal abdominal aortic aneurysm

    Institute of Scientific and Technical Information of China (English)

    GUO Wei; ZHANG Hong-peng; LIU Xiao-ping; JIA Xin; XIONG Jiang; MA Xiao-hui

    2013-01-01

    Background Endovascular stent-graft with fenestration can improve proximal sealing in patients with juxtarenal abdominal aortic aneurysm (JAAA).The purpose of this study was to describe our primary experience and evaluate the safety and efficacy of fenestrated device for JAAA in high-risk patients.Methods Between March 2011 and May 2012,nine male patients (mean age,(79.6±8.6) years) with asymptomatic JAAAs underwent elective deployment of the Zenith fenestrated stent-grafts at a single institution.All patients were treated in the hybrid operating room under general anesthesia.Follow-up computed tomography angiography (CTA) was routinely performed before discharge,at 3,6,and 12 months and annually thereafter.Results Procedural success was achieved in all cases.Total sixteen small fenestrations,two large fenestrations and eight scallops were used.Intra-operative complications occurred in four patients,which included one proximal type Ⅰ endoleak,two type Ⅱ endoleaks,and one renal artery dissection.The mean hospital stay was (8.9±1.4) days,mean blood loss was (360.5±46.8) ml,and mean iodinated contrast volume was (230.6±58.3) ml.The mean follow-up time was (7.6±4.2) months.The visceral graft patency was 100% until now.One patient had an increase of serum creatinine of more than 30%,but did not require dialysis.No patients died,no stent fractured,and migration were diagnosed during the follow-up.Conclusions The early results of fenestrated device for high-risk patients with complex JAAAs are satisfactory.However,long-term fenestrated graft durability and branch vessel patency remain to be determined.

  19. Transcriptional and phenotypic changes in aorta and aortic valve with aging and MnSOD deficiency in mice.

    Science.gov (United States)

    Roos, Carolyn M; Hagler, Michael; Zhang, Bin; Oehler, Elise A; Arghami, Arman; Miller, Jordan D

    2013-11-15

    The purpose of this study was to characterize changes in antioxidant and age-related gene expression in aorta and aortic valve with aging, and test the hypothesis that increased mitochondrial oxidative stress accelerates age-related endothelial and aortic valve dysfunction. Wild-type (MnSOD(+/+)) and manganese SOD heterozygous haploinsufficient (MnSOD(+/-)) mice were studied at 3 and 18 mo of age. In aorta from wild-type mice, antioxidant expression was preserved, although there were age-associated increases in Nox2 expression. Haploinsufficiency of MnSOD did not alter antioxidant expression in aorta, but increased expression of Nox2. When compared with that of aorta, age-associated reductions in antioxidant expression were larger in aortic valves from wild-type and MnSOD haploinsufficient mice, although Nox2 expression was unchanged. Similarly, sirtuin expression was relatively well-preserved in aorta from both genotypes, whereas expression of SIRT1, SIRT2, SIRT3, SIRT4, and SIRT6 were significantly reduced in the aortic valve. Expression of p16(ink4a), a marker of cellular senescence, was profoundly increased in both aorta and aortic valve from MnSOD(+/+) and MnSOD(+/-) mice. Functionally, we observed comparable age-associated reductions in endothelial function in aorta from both MnSOD(+/+) and MnSOD(+/-) mice. Interestingly, inhibition of NAD(P)H oxidase with apocynin or gp91ds-tat improved endothelial function in MnSOD(+/+) mice but significantly impaired endothelial function in MnSOD(+/-) mice at both ages. Aortic valve function was not impaired by aging or MnSOD haploinsufficiency. Changes in antioxidant and sirtuin gene expression with aging differ dramatically between aorta and aortic valve. Furthermore, although MnSOD does not result in overt cardiovascular dysfunction with aging, compensatory transcriptional responses to MnSOD deficiency appear to be tissue specific.

  20. Successful treatment by transcatheter aortic valve implantation of severe aortic regurgitation in a patient with ascending aorta prosthesis.

    Science.gov (United States)

    Rossi, Marco Luciano; Bocchi, Roberto; Barbaro, Cristina; Pagnotta, Paolo; Mennuni, Marco; Zavalloni, Dennis; Gasparini, Gabriele; Presbitero, Patrizia

    2013-05-01

    Severe aortic regurgitation (AR), when intervention is required, is managed by surgical aortic valve replacement (SAVR). Recently, transcatheter aortic valve replacement (TAVR) for severe aortic stenosis (AS) has shown non-inferiority to SAVR and superiority to medical management. TAVR could be a valid "off label" option to treat severe AR for patients unsuitable for SAVR due to their high surgical risk. Among aortic pathologies leading to severe AR, those involving the aortic root are considered as high risk procedures and thus prohibit TAVR. For these reasons TAVR is not an option for severe AR due to concomitant aortic root dilatation and degeneration. We report a successful case of TAVR for severe AR due to dilatation of degenerated tract of aortic root.

  1. Efeitos da atorvastatina, fluvastatina, pravastatina e simvastatina sobre a função endotelial, a peroxidação lipídica e a aterosclerose aórtica em coelhos hipercolesterolêmicos Effects of atorvastatin, fluvastatin, pravastatin, and simvastatin on endothelial function, lipid peroxidation, and aortic atherosclerosis in hypercholesterolemic rabbits

    Directory of Open Access Journals (Sweden)

    Paulo Afonso Ribeiro Jorge

    2005-04-01

    Full Text Available OBJETIVO: Comparar os efeitos da atorvastatina, fluvastatina, pravastatina e simvastatina sobre a função endotelial, a aterosclerose aórtica e o teor de malonodialdeído (MDA nas LDL nativas, oxidadas e na parede arterial de coelhos hipercolesterolêmicos, depois que as doses destas estatinas foram ajustadas para reduzir o colesterol total plasmático a valores similares. MÉTODOS: Coelhos machos, foram separados em grupos de 10 animais (n=10, chamados hipercolesterolêmico (controle, atorvastatina, fluvastatina, pravastatina e normal. A exceção do grupo normal, os animais foram alimentados com ração padrão acrescida de colesterol a 0,5% e óleo de coco a 2% durante 45 dias. As drogas foram administradas a partir do 15º dia do início do experimento e no 30º dia, as doses foram ajustadas, através do controle do colesterol plasmático, para obter valores semelhantes em cada grupo. Ao final do experimento foi dosado o colesterol plasmático e as lipoproteinas e retirado um segmento de aorta torácica para estudo da função endotelial, da peroxidação lipídica e exame histológico para medida da aterosclerose aórtica. RESULTADOS: As estatinas reduziram significantemente o colesterol total plasmático, as LDL-colesterol e a aterosclerose aórtica. O teor de MDA também foi significantemente reduzido nas LDL nativas e oxidadas, assim como na parede arterial. O relaxamento-dependente do endotélio foi significantemente maior no grupo tratado em comparação ao hipercolesterolêmico. CONCLUSÃO: As estatinas, em doses ajustadas, tiveram efeito significante e similar em reduzir a peroxidação lipídica nas LDL e na parede arterial, na regressão da aterosclerose aórtica e na reversão da disfunção endotelial.OBJECTIVE: To compare the effects of atorvastatin, fluvastatin, pravastatin, and simvastatin on endothelial function, aortic atherosclerosis, and the content of malondialdehyde (MDA in native and oxidized LDL and in the arterial

  2. The Kepler Input Catalog

    Science.gov (United States)

    Latham, D. W.; Brown, T. M.; Monet, D. G.; Everett, M.; Esquerdo, G. A.; Hergenrother, C. W.

    2005-12-01

    The Kepler mission will monitor 170,000 planet-search targets during the first year, and 100,000 after that. The Kepler Input Catalog (KIC) will be used to select optimum targets for the search for habitable earth-like transiting planets. The KIC will include all known catalogued stars in an area of about 177 square degrees centered at RA 19:22:40 and Dec +44:30 (l=76.3 and b=+13.5). 2MASS photometry will be supplemented with new ground-based photometry obtained in the SDSS g, r, i, and z bands plus a custom filter centered on the Mg b lines, using KeplerCam on the 48-inch telescope at the Whipple Observatory on Mount Hopkins, Arizona. The photometry will be used to estimate stellar characteristics for all stars brighter than K 14.5 mag. The KIC will include effective temperature, surface gravity, metallicity, reddening, distance, and radius estimates for these stars. The CCD images are pipeline processed to produce instrumental magnitudes at PSI. The photometry is then archived and transformed to the SDSS system at HAO, where the astrophysical analysis of the stellar characteristics is carried out. The results are then merged with catalogued data at the USNOFS to produce the KIC. High dispersion spectroscopy with Hectochelle on the MMT will be used to supplement the information for many of the most interesting targets. The KIC will be released before launch for use by the astronomical community and will be available for queries over the internet. Support from the Kepler mission is gratefully acknowledged.

  3. Challenging Friesian horse diseases : aortic rupture and megaesophagus

    NARCIS (Netherlands)

    Ploeg, M.

    2015-01-01

    Aortic rupture is quite rare in Warmblood horses and is best known as an acute and fatal rupture of the aortic root in older breeding stallions. It has now become clear that aortic rupture, which is diagnosed around an age of 4 years, is more frequent in the Friesian breed than in others. The high p

  4. The risk for type B aortic dissection in Marfan syndrome

    NARCIS (Netherlands)

    den Hartog, Alexander W.; Franken, Romy; Zwinderman, Aeilko H.; Timmermans, Janneke; Scholte, Arthur J.; van den Berg, Maarten P.; de Waard, Vivian; Pals, Gerard; Mulder, Barbara J. M.; Groenink, Maarten

    2015-01-01

    BACKGROUND: Aortic dissections involving the descending aorta are a major clinical problem in patients with Marfan syndrome. OBJECTIVES: The purpose of this study was to identify clinical parameters associated with type B aortic dissection and to develop a risk model to predict type B aortic dissect

  5. Outcome of pregnancy in patients after repair of aortic coarctation

    NARCIS (Netherlands)

    Vriend, JWJ; Drenthen, W; Pieper, PG; Roos-Hesselink, JW; Zwinderman, AH; van Veldhuisen, DJ; Mulder, BJM

    2005-01-01

    Aims Nowadays, most women born with aortic coarctation reach childbearing age. However, data on outcome of pregnancy in women after repair of aortic coarctation are scarce. The aim of this study was to report on maternal and neonatal outcome of pregnancy in women after aortic coarctation repair. Met

  6. Transcatheter Aortic Valve Implantation: Insights into Clinical Complications

    NARCIS (Netherlands)

    R.M.A. van der Boon (Robert)

    2014-01-01

    markdownabstract__Abstract__ Transcatheter Aortic Valve Implantation (TAVI) has emerged as a viable and safe treatment for patients with severe aortic stenosis (AS) who are considered ineligible or at prohibitive risk for Surgical Aortic Valve Replacement (SAVR)1–4. The aim of the present thesis wa

  7. Study of Coronary Artery Disease in Single Aortic Valvular Disease

    Institute of Scientific and Technical Information of China (English)

    张斌; 杨伟民; 占亚平

    2003-01-01

    Objectives To analyze the results of coronary angiographies (GAG) in patients with single aortic valvular heart disease; To study the relationship between aortic valve diseases and coronary artery disease (CAD). Methods 105 patients with single aortic valvular heart disease before surgery underwent angiography. The data of clinical characteristics and angiographies were analyzed. Results 51 patients had symptoms of angina pectoris among 105 patients with single aortic valvular heart disease. Seven of them were confirmed coronary artery disease by angiographies. Although the incidence of angina in aortic valve stenosis group was significantly higher than that in aortic valve regurgitation, the probability of combination of CAD in aortic valve stenosis group was similar to the later. However, the probability of combination of CAD in degenerative aortic valve group was significantly higher than the groups of rheumatic, congenitally bicuspid aortic valves, and other causes (p <0.01).Conclusions Angina pectoris is not sensitive for diagnosis of CAD in single aortic valve heart disease.The probability of combination of CAD in degenerative aortic valve disease is higher than that in aortic valve disease with other causes. Coronary angiography is strongly suggested for these patients.

  8. Mitral Valve Aneurysm: A Rare Complication of Aortic Valve Endocarditis

    Directory of Open Access Journals (Sweden)

    A Moaref

    2008-11-01

    Full Text Available A 20-year-old intravenous drug abuser man, refered to our hospital with dyspnea and orthopnea. Tranesophagealechocardiography revealed severe aortic regurgitation, healed vegetation of aortic valve and an aneurysm of theanterior leaflet of the mitral valve. The patient was discharged after aortic valve replacement and mitral valverepair.

  9. Heritable retinoblastoma and accelerated aortic valve disease

    Science.gov (United States)

    Abeyratne, L R; Kingston, J E; Onadim, Z; Dubrey, S W

    2013-01-01

    Heritable retinoblastoma is associated with a germline mutation in the tumour suppressor gene RBI. The Rb protein (pRb) arises from the RB1 gene, which was the first demonstrated cancer susceptibility gene in humans. 1 Second primary malignancies are recognised complications of retinoblastoma. Furthermore, pRb is implicated in valve remodelling in calcific aortic valve disease. 2 3 We report a family with hereditary retinoblastoma and associated secondary primary malignancies. There are two interesting aspects to this family. The first is the concept of ‘cancer susceptibility genes’; the RBI gene being the first reported in humans. A further feature of note is that two family members also have bicuspid aortic valves. We discuss a potential association between the gene defect responsible for retinoblastoma (with its associated propensity for further malignancies) and accelerated deterioration of the bicuspid aortic valve in the proband carrying this gene defect. PMID:23595191

  10. Serial Input Output

    Energy Technology Data Exchange (ETDEWEB)

    Waite, Anthony; /SLAC

    2011-09-07

    Serial Input/Output (SIO) is designed to be a long term storage format of a sophistication somewhere between simple ASCII files and the techniques provided by inter alia Objectivity and Root. The former tend to be low density, information lossy (floating point numbers lose precision) and inflexible. The latter require abstract descriptions of the data with all that that implies in terms of extra complexity. The basic building blocks of SIO are streams, records and blocks. Streams provide the connections between the program and files. The user can define an arbitrary list of streams as required. A given stream must be opened for either reading or writing. SIO does not support read/write streams. If a stream is closed during the execution of a program, it can be reopened in either read or write mode to the same or a different file. Records represent a coherent grouping of data. Records consist of a collection of blocks (see next paragraph). The user can define a variety of records (headers, events, error logs, etc.) and request that any of them be written to any stream. When SIO reads a file, it first decodes the record name and if that record has been defined and unpacking has been requested for it, SIO proceeds to unpack the blocks. Blocks are user provided objects which do the real work of reading/writing the data. The user is responsible for writing the code for these blocks and for identifying these blocks to SIO at run time. To write a collection of blocks, the user must first connect them to a record. The record can then be written to a stream as described above. Note that the same block can be connected to many different records. When SIO reads a record, it scans through the blocks written and calls the corresponding block object (if it has been defined) to decode it. Undefined blocks are skipped. Each of these categories (streams, records and blocks) have some characteristics in common. Every stream, record and block has a name with the condition that each

  11. Anesthesia Approach in Endovascular Aortic Reconstruction

    Directory of Open Access Journals (Sweden)

    Ayşin Alagöl

    2013-03-01

    Full Text Available Introduction: We have analyzed our initial results of our anesthesia techniques in our new-onset endovascular aortic reconstruction cases.Patients and Methods: The perioperative data of 15 elective and emergent endovascular aortic reconstruction cases that were operated in 2010-2011 were collected in a database. The choice of anesthesia was made by the risk factors, surgical team’s preferences, type and location of the aortic pathology and by the predicted operation duration. The data of local and general anesthesia cases were compared.Results: Thirteen (86.7% cases were male and 2 (13.3% female. Eleven patients were in ASA Class III. The demographic parameters, ASA classifications, concurrent diseases were similar in both groups. Thirteen (86.7% cases had infrarenal abdominal aortic aneurysm and 2 (13.3% had Type III aortic dissection. The diastolic arterial pressures were lower in general anesthesia group in 20th and 40th minutes’ measurements just like the mean arterial pressure measurements at the 40th, 100th minutes and during the deployment of the graft. Postoperative mortality occurred in 3 (20.0% patients and they all had general anesthesia and they were operated on emergency basis. Postoperative morbidity occurred in four patients that had general anesthesia (acute renal failure, multi-organ failure and pneumonia. The other patient had atrial fibrillation on the 1st postoperative day and was converted to sinus rhythm with amiodarone infusion.Conclusion: Edovascular aortic reconstruction procedures can safely be performed with both general and local anesthesia less invasively compared to open surgery. General anesthesia may be preferred for the better hemodynamic control.

  12. Aortic valve replacement in octogenarians

    Directory of Open Access Journals (Sweden)

    Dark John H

    2007-07-01

    Full Text Available Abstract Background and Aims As our population ages and life expectancy increases the number of people aged over 80 and more referred for cardiac surgery is growing. This study sought to identify the outcome of aortic valve replacement (AVR in octogenarians. Methods 68 patients aged 80 years or more underwent AVR at the Freeman Hospital, between April 2001 and April 2004. A retrospective review of the notes and outcomes from the patients' GP and the NHS strategic tracking service was performed. 54% (37 underwent isolated AVR whilst 46% (31 underwent combined AVR and CABG. Results Follow up was 100% complete. The mean age was 83.1 ± s.d. 2.9 years, a mean gradient of 83 ± s.d. 31 mmHg and mean AVA of 0.56 cm2. The mean additive EuroSCORE was 8.6 ± s.d. 1.2, the logistic EuroSCORE mean 12.0 ± s.d. 5.9. In hospital 30 day mortality was 13 %. Survival was 80% at 1 year and 78% at 2 years. Median follow up was for 712 days. Stepwise logistic regression identified chronic obstructive airways disease as an independent predictor of mortality (p Conclusion Our study demonstrates that the operative mortality for AVR in the over eighties is good, whilst the mid to long term outcome is excellent There is a very low attrition rate with those undergoing the procedure living as long than their age matched population. This study confirms AVR is a safe, acceptable treatment for octogenarians with excellent mid term outcomes.

  13. The changes in various hydroxyproline fractions in aortic tissue of rabbits are closely related to the progression of atherosclerosis

    Directory of Open Access Journals (Sweden)

    Alhomida AS

    2010-03-01

    Full Text Available Abstract Background The most important function of collagen and elastin is to induce several mechanical parameters which are known to play a dominant role in governing mechanical properties of the blood vessels. The aortic tissue of rabbit is one of the important sources of collagen and elastin. The effects of high fat diet (HFD on the hydroxyproline (Hyp fractions in serum and aortic tissues of rabbits and collagen content in the aortic tissues of rabbits have not been documented before. The present study was undertaken to investigate the changes in Hyp fractions in serum and aortic tissues of rabbits and collagen content in the aortic tissues of rabbits during the progression of atherosclerosis. The atherosclerotic model used in this study was the New Zealand white rabbit (male; 12 weeks old. Twenty five rabbits were individually caged, and divided into control group (NOR; n = 10 and HFD group (CHO; n = 15. The control group was fed (100 g/day of normal (NOR diet for a period of 15 weeks. The HFD group was fed normal diet supplemented with 1.0% cholesterol plus 1.0% olive oil (100 g/day for the same period of time. Results We found that the TC, LDLC, and TG (mg/dl were significantly (p Conclusions These results suggest that percentage decrease in various Hyp fractions in aortic tissue of HFD rabbits are closely related to percentage decrease of collagen content in aortic tissues of HFD rabbits. These results also suggest that it may be possible to use the changes in various Hyp fractions in aortic tissues of rabbits as an important risk factor during the progression of atherosclerosis.

  14. Influence of aerobic exercise training on post-exercise responses of aortic pulse pressure and augmentation pressure in postmenopausal women

    Directory of Open Access Journals (Sweden)

    Nobuhiko eAkazawa

    2015-10-01

    Full Text Available Central arterial blood pressure (BP is more predictive of future cardiovascular events than is brachial BP because it reflects the BP load imposed on the left ventricle with greater accuracy. However, little is known about the effects of exercise training on central hemodynamic response to acute exercise. The purpose of the present study was to determine the influence of an aerobic exercise regimen on the response of aortic BP after a single aerobic exercise in postmenopausal women. Nine healthy postmenopausal women (age: 61 ± 2 years participated in a 12-week aerobic exercise training regimen. Before and after the training, each subjects performed a single bout of cycling at ventilatory thresholds for 30 min. We evaluated the post-exercise aortic BP response, which was estimated via the general transfer function from applanation tonometry. After the initial pre-training aerobic exercise session, aortic BP did not change significantly: however, aortic pulse pressure and augmentation pressure were significantly attenuated after the single aerobic exercise session following the 12-week training regimen. The present study demonstrated that a regular aerobic exercise training regimen induced the post-exercise reduction of aortic pulse pressure and augmentation pressure. Regular aerobic exercise training may enhance post-exercise reduction in aortic BP.

  15. Idiopathic thoracic aortic aneurysm at pediatric age.

    Science.gov (United States)

    Marín-Manzano, E; González-de-Olano, D; Haurie-Girelli, J; Herráiz-Sarachaga, J I; Bermúdez-Cañete, R; Tamariz-Martel, A; Cuesta-Gimeno, C; Pérez-de-León, J

    2009-03-01

    A 6-year-old-boy presented with epigastric pain and vomiting over 1 year. Chest X-ray and esophagogastric transit showed a mediastinal mass. A chest computerized tomography angiogram demonstrated a descending thoracic aortic aneurysm. Analytical determinations carried out were all negative. The aneurysm was surgically repaired using a Dacron patch. The anatomopathological study described atherosclerotic lesions with calcifications, compatible with an atherosclerotic aneurysm wall. Aneurysms are uncommon in the pediatric population. Usually, no pathogenesis can be determined, and thus, such cases are grouped as idiopathic. Direct repair with or without patch is a therapeutic alternative in pediatric aneurysms and can allow the growth of the aortic circumference.

  16. Infective endocarditis following transcatheter aortic valve replacement-

    DEFF Research Database (Denmark)

    Loh, Poay Huan; Bundgaard, Henning; S�ndergaard, Lars

    2013-01-01

    Transcatheter aortic valve replacement (TAVR) can improve the symptoms and prognosis of patients with severe aortic stenosis who, due to a high expected operative risk, would not have otherwise been treated surgically. If these patients develop prosthetic valve endocarditis, their presentations may...... be atypical causing a delay in the diagnosis and treatment. The management is also complicated by their comorbidities, and surgical treatment may not be feasible leading to a significant morbidity and mortality. We describe a case of an 85-year-old man with TAVI prosthetic valve endocarditis successfully...

  17. Supravalvular aortic stenosis with sudden cardiac death

    Directory of Open Access Journals (Sweden)

    Pradeep Vaideeswar

    2015-01-01

    Full Text Available Sudden cardiac death (SCD most commonly results from previously undiagnosed congenital, acquired, or hereditary cardiac diseases. Congenital aortic valvular, subvalvular, and supravalvular disease with left ventricular outflow tract obstruction is an important preventable cause of sudden death. This report documents sudden death presumably due to acute myocardial ischemia in a young male with an undiagnosed supravalvular aortic stenosis (SVAS due to a rare association of isolation of coronary sinuses of Valsalva. Congenital supravalvular pulmonary stenosis and mitral valvular dysplasia were also present.

  18. Infected abdominal aortic aneurysm due to Morganella morganii: CT findings.

    Science.gov (United States)

    Kwon, Oh Young; Lee, Jong Seok; Choi, Han Sung; Hong, Hoon Pyo; Ko, Young Gwan

    2011-02-01

    An infected aortic aneurysm, or mycotic aneurysm, is a rare arterial dilatation due to destruction of the infected vessel wall. Common pathogens resulting in an infected aortic aneurysm are Salmonella and Clostridium species, as well as Staphylococcus aureus; Morganella morganii, on the other hand, is very rare. An infected abdominal aortic aneurysm has tendencies to grow rapidly and to rupture. The mortality rate is high in patients undergoing emergent surgical intervention. We report the case of a 65-year-old man who presented with an infected abdominal aortic aneurysm caused by M. morganii. A high index of suspicion and imaging tests are necessary in order to diagnose an infected aortic aneurysm.

  19. Treatment of infrarenal abdominal aortic dissection concomitant with an aneurysm

    Institute of Scientific and Technical Information of China (English)

    WANG Li-xin; ZHU Ting; FU Wei-guo; WANG Yu-qi; XI Xun; GUO Da-qiao; CHEN Bin; JIANG Jun-hao; YANG Ju; SHI Zhen-yu

    2007-01-01

    @@ Aortic dissection occurs when layers of the aortic walls are separated by the blood flow through an intimal tear. Dissection of the aorta most frequently originates in the ascending aorta (70%), followed by the descending aorta (22%), the aortic arch (7%) and the abdominal aorta (1/%).1 The dissection limited to the abdominal aorta is rare.2 An isolated abdominal aortic dissection (IAAD) concomitant with an abdominal aortic aneurysm (AAA) is uncommon. We present here one patient with IAAD and AAA treated by endovascular therapy.

  20. 主动脉瓣环扩大术在主动脉瓣置换术中的应用%Aortic annulus enlargement in aortic valve replacement for small aortic annulus

    Institute of Scientific and Technical Information of China (English)

    朱水波; 殷桂林; 胡健才; 张殿堂; 张晓明; 王荣平; 谭焱; 高旭辉; 刘勇

    2012-01-01

    Objective To summarize the experiences of aortic annulus enlargement in aortic valve replacement for small aortic annulus. Methods From Jan. 2000 to Sept,2010,18 cases of aortic valve disease with small aortic annulus received improved Manouguian procedure to enlarge the small aortic annulus before implanting appropriate mechanical aortic valve. Complicated heart lesion were treated surgically simultaneously. Results Complications in early stage including ventricular arrhythmia, severe low cardiac output syndrome and cardiac tamponade were cured. All cases were discharged without operative mortality. All cases were improved in cardiac function and ventricular wall mass. No death or other severe events occurred in follow - up. Conclusion Aortic annulus enlargement with improved Manougnian method is effective and safe in patients with small aortic annulus in order to implant appropriate mechanical aortic valve.%目的 总结主动脉瓣置换术中处理小主动脉瓣环的体会.方法 我院在2000年至2010年期间收治主动脉瓣环细小的主动脉瓣病变18例,均采取改良Manouguian方法扩大主动脉瓣环,再置入较合适的机械主动脉瓣.同期行二尖瓣置换6例,室间隔修补1例,三尖瓣成形5例.结果 17例有效开口面积指数(EOAI)均达到0.85cm2/m2以上,1例0.80cm2/m2.术后严重低心排综合征1例,室性心律失常3例,心脏压塞1例.18例痊愈出院,随访1~10年,术后6个月复查发现EOAI为0.80cm2/m2的患者主动脉跨瓣压差较高,室间隔及左室壁厚度恢复较慢,左室射血分数较低;而比值在0.85~1.0之间与大于1.0的患者相比,主动脉跨瓣压差、室间隔及左室壁厚度平均值稍高,但差异无统计学意义.2例术后6年因身高、体重增加EOAI分别下降到0.79、0.81cm2/m2,出现活动后心慌,心电图提示左室高电压,经扩管等药物治疗和一般处理,症状明显改善.结论 改良Manouguian方法扩大主动脉瓣环安全、有效,可置入

  1. Clinical indicators of paraplegia underplay universal spinal cord neuronal injury from transient aortic occlusion.

    Science.gov (United States)

    Bell, Marshall T; Puskas, Ferenc; Bennett, Daine T; Cleveland, Joseph C; Herson, Paco S; Mares, Joshua M; Meng, Xainzhong; Weyant, Michael J; Fullerton, David A; Brett Reece, T

    2015-08-27

    Paraplegia following complex aortic intervention relies on crude evaluation of lower extremity strength such as whether the patient can lift their legs or flex the ankle. Little attention has been given to the possible long-term neurologic sequelae following these procedures in patients appearing functionally normal. We hypothesize that mice subjected to minimal ischemic time will have functional and histological changes despite the gross appearance of normal function. Male mice underwent 3 min of aortic occlusion (n=14) or sham surgery (n=4) via a median sternotomy. Neurologic function was graded by Basso Motor Score (BMS) preoperatively and at 24h intervals after reperfusion. Mice appearing functionally normal and sham mice were placed on a walking beam and recorded on high-definition, for single-frame motion analysis. After 96 hrs, spinal cords were removed for histological analysis. Following 3 min of ischemia, functional outcomes were split evenly with either mice displaying almost normal function n=7 or near complete paraplegia n=7. Additionally, single-frame motion analysis revealed significant changes in gait. Histologically, there was a significant stepwise reduction of neuronal viability, with even the normal function ischemic group demonstrating significant loss of neurons. Despite the appearance of normal function, temporary ischemia induced marked cyto-architectural changes and neuronal degeneration. Furthermore high-definition gait analysis revealed significant changes in gait and activity following thoracic aortic occlusion. These data suggest that all patients undergoing procedures, even with short ischemic times, may have spinal cord injury that is not evident clinically.

  2. Aortic root and proximal aortic arch replacement (performed by a left-handed surgeon).

    Science.gov (United States)

    Carrel, Thierry

    2017-01-01

    We present our standard technique of composite graft replacement performed by a left-handed surgeon. This procedure is performed with a 30-day mortality comparable to that of elective isolated aortic valve replacement.

  3. The role of balloon aortic valvuloplasty in the era of transcatheter aortic valve implantation

    Science.gov (United States)

    Wilczek, Krzysztof; Pres, Damian; Krajewski, Adam; Poloński, Lech; Zembala, Marian; Gąsior, Mariusz

    2015-01-01

    Balloon aortic valvuloplasty is recommended in patients not suitable for transcatheter aortic valve implantation/aortic valve replacement (TAVI/AVR) or when such interventions are temporarily contraindicated. The number of performed balloon aortic valvuloplasty (BAV) procedures has been increasing in recent years. Valvuloplasty enables the selection of individuals with severe left ventricular dysfunction or with symptoms of uncertain origin resulting from concomitant disorders (including chronic obstructive pulmonary disease [COPD]) who can benefit from destination therapy (AVR/TAVI). Thanks to improved equipment, the number of adverse effects is now lower than it was in the first years after the advent of BAV. Valvuloplasty can be safely performed even in unstable patients, but long-term results remain poor. In view of the limited availability of TAVI in Poland, it is reasonable to qualify patients for BAV more often, as it is a relatively safe procedure improving the clinical condition of patients awaiting AVR/TAVI. PMID:26336471

  4. Congenital quadricuspid aortic valve: analysis of 11 surgical cases

    Institute of Scientific and Technical Information of China (English)

    TANG Yang-feng; XU Ji-bin; HAN Lin; LU Fang-lin; LANG Xi-long; SONG Zhi-gang; XU Zhi-yun

    2011-01-01

    Background Congenital quadricuspid aortic valve is rarely seen during aortic valve replacement (AVR).The diagnosis and treatment of the disease were reported in 11 cases.Methods Eleven patients (nine men and two women,mean age 33.4 years) with quadricuspid aortic valve were retrospectively evaluated.Medical records,echocardiograms and surgical treatment were reviewed.Results In accordance with the Hurwitz and Roberts classification,the patients were classified as type A (n=2),type B (n=7),type F (n=1) and type G (n=1).Three patients were associated with other heart diseases,including infective endocarditis and mitral prolaps,left superior vena cava,aortic aneurysm.All had aortic regurgitation (AR) except two with aortic stenosis (AS),detected by color-flow Doppler echocardiography.The congenital quadricuspid aortic valve deformity in seven patients was diagnosed by echocardiography.All patients underwent successful aortic valve replacement.Conclusion Quadricuspid aortic valve is a rare cause of aortic insufficiency,while echocardiography plays an important role in diagnosing the disease.Aortic valve replacement is the major therapy for the disease.

  5. Factors influencing long-term survival after aortic valve replacement.

    Directory of Open Access Journals (Sweden)

    Shigenobu,Masaharu

    1980-06-01

    Full Text Available In the aortic stenosis group, the left ventricular (LV muscle mass index was a good parameter for predicting the prognosis. Associated mitral valve disease had no influence on long term survival after aortic valve replacement. In the aortic insufficiency group, associated mitral valve disease had a marked influence on the results of aortic valve replacement. In general, the aortic insufficiency group had less clinical improvement postoperatively than the aortic stenosis group. In the annuloaortic ectasia group, left ventricular enddiastolic pressure (LVEDP might be the predictor to the prognosis. This group had the worst prognosis, of the three groups. Early operation should be considered for patients who have no, or only mild symptoms of, aortic valve disease.

  6. Aortic Remodeling Following Transverse Aortic Constriction in Mice is Attenuated with AT1 Receptor Blockade

    Science.gov (United States)

    Kuang, Shao-Qing; Geng, Liang; Prakash, Siddharth K.; Cao, Jiu-Mei; Guo, Steven; Villamizar, Carlos; Kwartler, Callie S.; Ju, Xiaoxi; Brasier, Allan R.; Milewicz, Dianna M.

    2016-01-01

    Objective Although hypertension is the most common risk factor for thoracic aortic diseases, it is not understood how increased pressures on the ascending aorta lead to aortic aneurysms. We investigated the role of Ang II type 1 (AT1) receptor activation in ascending aortic remodeling in response to increased biomechanical forces using a transverse aortic constriction (TAC) mouse model. Approach and Results Two weeks after TAC, the increased biomechanical pressures led to ascending aortic dilatation, aortic wall thickening and medial hypertrophy. Significant adventitial hyperplasia and inflammatory responses in TAC ascending aortas were accompanied by increased adventitial collagen, elevated inflammatory and proliferative markers, and increased cell density due to accumulation of myofibroblasts and macrophages. Treatment with losartan significantly blocked TAC induced vascular inflammation and macrophage accumulation. However, losartan only partially prevented TAC induced adventitial hyperplasia, collagen accumulation and ascending aortic dilatation. Increased Tgfb2 expression and phosphorylated-Smad2 staining in the medial layer of TAC ascending aortas was effectively blocked with losartan. In contrast, the increased Tgfb1 expression and adventitial phospho-Smad2 staining were only partially attenuated by losartan. In addition, losartan significantly blocked Erk activation and ROS production in the TAC ascending aorta. Conclusions Inhibition of the AT1 receptor using losartan significantly attenuated the vascular remodeling associated with TAC but did not completely block the increased TGF- β1 expression, adventitial Smad2 signaling and collagen accumulation. These results help to delineate the aortic TGF-β signaling that is dependent and independent of the AT1 receptor after TAC. PMID:23868934

  7. [Evaluation of aortic valve replacement involving small severely calcified aortic annulus in elderly patients].

    Science.gov (United States)

    Iwahashi, M; Nishimura, Y; Hiramatsu, K; Komori, S; Shibata, M; Yuzaki, M; Okamura, Y

    2006-04-01

    We performed aortic valve replacement in 24 patients aged over 70 with small calcified valves. The surgical management of such patients remains controversial as the extensive calcification compromises implantation. Hence, we used an ultrasonic debridement instrument to remove calcium and selected a small prosthesis with the largest possible orifice without enlargement of the aortic annulus. Echocardiography showed significant reductions in left ventricular mass index compared with preoperative values. Early and mid-term prognosis has been relatively good.

  8. Minimally invasive aortic valve replacement – pros and cons of keyhole aortic surgery

    OpenAIRE

    Kaczmarczyk, Marcin; Szałański, Przemysław; Zembala, Michał; Filipiak, Krzysztof; Karolak, Wojciech; Wojarski, Jacek; Garbacz, Marcin; Kaczmarczyk, Aleksandra; Kwiecień, Anna; Zembala, Marian

    2015-01-01

    Over the last twenty years, minimally invasive aortic valve replacement (MIAVR) has evolved into a safe, well-tolerated and efficient surgical treatment option for aortic valve disease. It has been shown to reduce postoperative morbidity, providing faster recovery and rehabilitation, shorter hospital stay and better cosmetic results compared with conventional surgery. A variety of minimally invasive accesses have been developed and utilized to date. This concise review demonstrates and discus...

  9. Effect of transcatheter aortic valve implantation on QT dispersion in patients with aortic stenosis

    Institute of Scientific and Technical Information of China (English)

    Hakan Erkan; kr elik; Engin Hatem; Mustafa Tark Aa; Levent Korkmaz; Teyyar Gkdeniz; Ahmet arAykan; Ezgi Kalaycolu; Faruk Boyac; mer Faruk rakolu

    2014-01-01

    Background QT dispersion (QTd) is a predictor of ventricular arrhythmia. Ventricular arrhythmia is an important factor influencing morbidity and mortality in patients with aortic stenosis. Surgical aortic valve replacement reduced the QTd in this patients group. However, the effect of transcatheter aortic valve implantation (TAVI) on QTd in patients with aortic stenosis is unknown. The aim of this study was to investigate the effect of TAVI on QTd in patients with aortic stenosis. Methods Patients with severe aortic stenosis, who were not candi-dates for surgical aortic valve replacement due to contraindications or high surgical risk, were included in the study. All patients underwent electrocardiographic and echocardiographic evaluation before, and at the 6th month after TAVI, computed QTd and left ventricular mass index (LVMI). Results A total 30 patients were admitted to the study (mean age 83.2 ± 1.0 years, female 21 and male 9, mean valve area 0.7 ± 3 mm2). Edwards SAPIEN heart valves, 23 mm (21 patients) and 26 mm (9 patients), by the transfemoral approach were used in the TAVI procedures. All TAVI procedures were successful. Both QTd and LVMI at the 6th month after TAVI were significantly reduced com-pared with baseline values of QTd and LVMI before TAVI (73.8 ± 4 ms vs. 68 ± 2 ms, P=0.001 and 198 ± 51 g/m² vs. 184 ± 40 g/m², P=0.04, respectively). There was a significant correlation between QTd and LVMI (r=0.646, P<0.001). Conclusions QTd, which malign ventricular arrhythmia marker, and LVMI were significantly reduced after TAVI procedure. TAVI may decrease the possibility of ventricu-lar arrhythmia in patients with aortic stenosis.

  10. A rare case of aortic sinuses of valsalva fistula to multiple cardiac chambers secondary to periannular aortic abscess formation from underlying Brucella endocarditis

    Directory of Open Access Journals (Sweden)

    Sabzi, Feridoun

    2015-11-01

    Full Text Available The concomitant presence of abnormal connection from three aortic valsalva sinuses to cardiac chambers is a rare complication of native aortic endocarditis. This case report presents a 37-year-old Iranian female patient who had native aortic valve endocarditis complicated by periannular abscess formation and subsequent perforation to multi-cardiac chambers associated with congestive heart failure and left bundle branch block. Multiple aorto-cavitary fistulas to right atrium, main pulmonary artery, and formation of a pocket over left atrial roof were detected by transthoracic echocardiogram (TTE. She had received a full course of antibiotics therapy in a local hospital and was referred to our center for further surgery. TTE not only detected multiple aorto-cavitary fistulas but also revealed large vegetation in aortic and mitral valve leaflets and also small vegetation in the entrance of fistula to right atrium. However, the tricuspid valve was not involved in infective endocarditis. She underwent open cardiac surgery with double valve replacement with biologic valves and reconstruction of left sinus of valsalva fistula to supra left atrial pocket by pericardial patch repair. The two other fistulas to main pulmonary artery and right atrium were closed via related chambers. The post-operative course was complicated by renal failure and prolonged dependency to ventilator that was managed accordingly with peritoneal dialysis and tracheostomy. The patient was discharged on the 25 day after admission in relatively good condition. The TTE follow-up one year after discharge revealed mild paravalvular leakage in aortic valve position, but the function of mitral valve was normal and no residual fistulas were detected.

  11. Aortic valve leaflet replacement with bovine pericardium to preserve native dynamic capabilities of the aortic annulus.

    Science.gov (United States)

    Kim, Kyung Hwa; Choi, Jong Bum; Kim, Min Ho; Kim, Won Ho; Lee, Mi Kyung; Lee, Sam Youn

    2014-02-01

    Valve replacement is typically the most appropriate option for treating aortic valve stenotic insufficiency. However, neither mechanical nor bioprosthetic replacement components preserve the circumferential expansion and contraction of a native aortic annulus during the cardiac cycle, because the prosthetic ring is affixed to the annulus. A 64-year-old man presented with a bicuspid and stenotic aortic valve, and the native annulus was too small to accommodate a porcine replacement valve. We fashioned new aortic leaflets from bovine pericardium with use of a template, and we affixed the sinotubular junction with use of inner and outer stabilization rings. Postoperative echocardiograms revealed coaptation of the 3 new leaflets with no regurgitation. At the patient's 5.5-year follow-up examination, echocardiograms showed flexible leaflet movement with a coaptation height of 7 mm, and expansion and contraction of the aortic annulus similar to that of a normal native annulus. The transvalvular pressure gradient was insignificant. If long-term durability of the new leaflets is confirmed, this method of leaflet replacement and fixation of the sinotubular junction might serve as an acceptable alternative to valve replacement in the treatment of aortic valve stenosis. We describe the patient's case and present our methods and observations.

  12. Aortic root aneurysm in an adult patient with aortic coarctation: a single-stage approach.

    Science.gov (United States)

    Ananiadou, Olga G; Koutsogiannidis, Charilaos; Ampatzidou, Fotini; Drossos, George E

    2012-09-01

    Coarctation of the aorta is a common congenital defect that may be undiagnosed until adulthood. Moreover, coarctation is associated with congenital and acquired cardiac pathology that may require surgical intervention. The management of an adult patient with aortic coarctation and an associated cardiac defect poses a great technical challenge since there are no standard guidelines for the therapy of such a complex pathology. Several extra-anatomic bypass grafting techniques have been described, including methods in which distal anastomosis is performed on the descending thoracic aorta, allowing simultaneous intracardiac repair. We report here a 37-year old man who was diagnosed with an aortic root aneurysm and aortic coarctation. The patient was treated electively with a single-stage approach through a median sternotomy that consisted of valve-sparing replacement of the aortic root and ascending-to-descending extra-anatomic aortic bypass, using a 18-mm Dacron graft. Firstly, the aortic root was replaced with the Yacoub remodelling procedure, and then the distal anastomosis was performed to the descending aorta, behind the heart, with the posterior pericardial approach. The extra-anatomic bypass graft was brought laterally from the right atrium and implanted in the ascending graft. Postoperative recovery was uneventful and a control computed tomographic angiogram 1 month after complete repair showed good results.

  13. Medtronic Freestyle Aortic Root Bioprosthesis Implantation for the Infective Endocarditis on Aortic Root

    Directory of Open Access Journals (Sweden)

    Zekeriya Arslan

    2013-10-01

    Full Text Available    Infective endocarditis and periannular abscess formation are serious problems in cardiac valve surgery, requiring extensive surgical debridement and reconstruction of the aortic annulus. We aimed to report two cases which were successfully treated with bioprosthetic valve implantation for infective endocarditis. Transosephageal echocardiography were performed for the diagnosis of one prosthetic and one native destructive aortic valve endocarditis in association with congestive heart failure (NYHA class-VI and abscess formation. Medtronic Freestyle stentless aortic root bioprosthesis was implanted into the left ventricular outflow tract after surgical radical aortic root debridement for each patient followed with medical treatment, which was extended to six weeks. Neither early nor late mortality was detected. One patient required prolonged ventilatory support (two days and permanent DDD-R pacing. Echocardiography showed no signs of valve dysfunction or recurrent endocarditis for both patients in 10 months follow up.Medtronic Freestyle stentless aortic root bioprosthesis may be a good alternative way of treatment to aortic valve and root endocarditis instead of homograft.

  14. Cross Talk between NOTCH Signaling and Biomechanics in Human Aortic Valve Disease Pathogenesis

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    Richard C. Godby

    2014-12-01

    Full Text Available Aortic valve disease is a burgeoning public health problem associated with significant mortality. Loss of function mutations in NOTCH1 cause bicuspid aortic valve (BAV and calcific aortic valve disease. Because calcific nodules manifest on the fibrosa side of the cusp in low fluidic oscillatory shear stress (OSS, elucidating pathogenesis requires approaches that consider both molecular and mechanical factors. Therefore, we examined the relationship between NOTCH loss of function (LOF and biomechanical indices in healthy and diseased human aortic valve interstitial cells (AVICs. An orbital shaker system was used to apply cyclic OSS, which mimics the cardiac cycle and hemodynamics experienced by AVICs in vivo. NOTCH LOF blocked OSS-induced cell alignment in human umbilical vein endothelial cells (HUVECs, whereas AVICs did not align when subjected to OSS under any conditions. In healthy AVICs, OSS resulted in decreased elastin (ELN and α-SMA (ACTA2. NOTCH LOF was associated with similar changes, but in diseased AVICs, NOTCH LOF combined with OSS was associated with increased α-SMA expression. Interestingly, AVICs showed relatively higher expression of NOTCH2 compared to NOTCH1. Biomechanical interactions between endothelial and interstitial cells involve complex NOTCH signaling that contributes to matrix homeostasis in health and disorganization in disease.

  15. COMPARISON OF PREOPERATIVE NONINVASIVE AND INTRAOPERATIVE MEASUREMENTS OF AORTIC ANNULUS

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    Manish Hinduja

    2016-10-01

    Full Text Available BACKGROUND Precise preoperative assessment of aortic annulus diameter is essential for sizing of aortic valve especially in patients planned for transcatheter aortic valve replacement. Computed Tomographic (CT and echocardiographic measurements of the aortic annulus vary because of elliptical shape of aortic annulus. This study was undertaken to compare the measurement of aortic annulus intraoperatively with preoperative noninvasive methods in patients undergoing aortic valve replacement. MATERIALS AND METHODS Aortic annulus diameter was measured with cardiac CT and Transesophageal Echocardiography (TEE prior to open aortic valve replacement in 30 patients with aortic valve stenosis. In CT, aortic annulus dimensions were measured in coronal plane, sagittal oblique plane and by planimetry. Both 2-dimensional and 3-dimensional TEE were used. These were compared with intraoperative measurements done by valve sizers and Hegar dilators. Pearson analysis was applied to test for degree of correlation. RESULTS CT in coronal and sagittal oblique plane tends to overestimate the diameter of aortic annulus when compared with intraoperative measurements (coefficient of relation, r = 0.798 and 0.749, respectively. CT measurements in single oblique plane showed a weaker correlation with intraoperative measurements than 3D TEE and 2D TEE (r = 0.917 and 0.898, respectively. However, CT measurements by planimetry method were most correlating with the intraoperative measurements (r = 0.951. CONCLUSION Noninvasive investigations with 3-dimensional views (CT-based measurement employing calculated average diameter assessment by planimetry and 3-dimensional TEE showed better correlation with intraoperative measurement of aortic annulus. CT-based aortic annulus measurement by planimetry seems to provide adequate dimensions most similar to operative measurements.

  16. Conservative aortic valve surgery in adults

    NARCIS (Netherlands)

    Casselman, F.P.A.

    2001-01-01

    118 Chapter 1 reviews the current knowledge of the aortic valve. The normal anatomy and possible variations are described. The different pathological conditions are explained as wel as their natural history and the indications for intervention. The various surgical options with regard to the patholo

  17. The future of transcatheter aortic valve implantation.

    Science.gov (United States)

    Hamm, Christian W; Arsalan, Mani; Mack, Michael J

    2016-03-01

    Since the introduction of transcatheter aortic valve implantation (TAVI) into clinical practice, the treatment of aortic stenosis has changed dramatically. In the past, medical therapy with or without balloon aortic valvuloplasty was the only option for inoperable patients. More recently, TAVI has become the treatment of choice for these patients and the preferred alternative for high-risk operable patients. Surgical aortic valve replacement (SAVR) currently remains the gold standard for patients at low or intermediate operative risk. As randomized trials have demonstrated comparable results between TAVI and SAVR in the high-risk population, there is now a clear trend towards performing TAVI even in intermediate-risk patients while awaiting the results of randomized trials in that population. Nevertheless, there are still questions regarding TAVI involving paravalvular leak (PVL), stroke, pacemaker requirements, and durability that remain to be more definitively answered before TAVI can routinely be performed in a broader, lower risk population. Improvements in patient selection, imaging, and second and third generation devices have decreased the incidence of PVLs and vascular complications that followed the earliest TAVI procedures, but the rates of perioperative stroke and permanent pacemaker implantation must still be addressed. Furthermore, the long-term durability of TAVI devices and a role for post-procedure antithrombotic management remain unanswered. Until these questions are more clearly answered, it is the Heart Team's task to determine the optimal treatment for each patient based on risk scores, frailty metrics, comorbidities, patient preference, and potential for improvement in quality of life.

  18. Painless aortic dissection presenting as paraplegia.

    Science.gov (United States)

    Colak, Necmettin; Nazli, Yunus; Alpay, Mehmet Fatih; Akkaya, Ismail Olgun; Cakir, Omer

    2012-01-01

    Acute dissection of the aorta can be life-threatening. As a presenting manifestation of aortic dissection, neurologic complications such as paraplegia are rare. Herein, we report the case of a 51-year-old man who presented with sudden-onset paraplegia and ischemia of the legs, with no chest or back pain. His medical history included coronary artery bypass grafting. Physical examination revealed pulseless lower extremities, and computed tomography showed aortic dissection from the ascending aorta to the common iliac arteries bilaterally. A lumbar catheter was inserted for cerebrospinal fluid drainage, and axillary arterial cannulation was established. With the use of cardiopulmonary bypass, the aortic dissection was corrected, and the previous coronary artery grafts were reattached. The surgery restored spinal and lower-extremity perfusion, and the patient walked unaided from the hospital upon his discharge 5 days later. Although acute aortic dissection presenting as paraplegia is rare, it should be considered in patients who have pulseless femoral arteries bilaterally and sudden-onset paraplegia, despite no pain in the chest or back. Prompt diagnosis and intervention can prevent morbidity and death.

  19. [Albert Einstein and his abdominal aortic aneurysm].

    Science.gov (United States)

    Cervantes Castro, Jorge

    2011-01-01

    The interesting case of Albert Einstein's abdominal aortic aneurysm is presented. He was operated on at age 69 and, finding that the large aneurysm could not be removed, the surgeon elected to wrap it with cellophane to prevent its growth. However, seven years later the aneurysm ruptured and caused the death of the famous scientist.

  20. Fatal Saccharomyces Cerevisiae Aortic Graft Infection

    Science.gov (United States)

    Meyer, Michael (Technical Monitor); Smith, Davey; Metzgar, David; Wills, Christopher; Fierer, Joshua

    2002-01-01

    Saccharomyces cerevisiae is a yeast commonly used in baking and a frequent colonizer of human mucosal surfaces. It is considered relatively nonpathogenic in immunocompetent adults. We present a case of S. cerevisiae fungemia and aortic graft infection in an immunocompetent adult. This is the first reported case of S. cerevisiue fungemia where the identity of the pathogen was confirmed by rRNA sequencing.

  1. Aortic thrombus formation during a Seldinger aortography

    Energy Technology Data Exchange (ETDEWEB)

    Kiermayer, H.

    1984-12-01

    Acute aortic thrombosis is a rarely described complication of angiography with the technique of arterial catheterization. In the presented case record, a sudden therapy-resistant rise in blood pressure was accompanied by paraplegia of the lower limbs. The activation of the coagulation system caused by the heterogeneous material brought into the aorta, combined with severe arteriosclerosis, is discussed as a possible cause.

  2. Severe aortic valve stenosis and nosebleed

    NARCIS (Netherlands)

    Schoedel, Johannes; Obergfell, Achim; Maass, Alexander H.; Schodel, Johannes

    2007-01-01

    Aortic valve stenosis is known to be associated with loss of high molecular von Willebrand multimers. This can lead to gastrointestinal bleeding in patients with gastrointestinal angiodysplasia, the Heyde syndrome. Here we present a case of anaemia and severe epistaxis associated with acquired von W

  3. Noncardiac surgery in patients with aortic stenosis

    DEFF Research Database (Denmark)

    Andersson, Charlotte; Jørgensen, Mads Emil; Martinsson, Andreas

    2014-01-01

    BACKGROUND: Past research has identified aortic stenosis (AS) as a major risk factor for adverse outcomes in noncardiac surgery; however, more contemporary studies have questioned the grave prognosis. To further our understanding of this, the risks of a 30-day major adverse cardiovascular event...

  4. Systolic time intervals in congenital aortic stenosis.

    NARCIS (Netherlands)

    Moene, Rudolf Johannens

    1974-01-01

    Obstruction to left ventricular outflow may occur at the valvular, subvalvular and Supravalvular level. The most common congenital forms are valvular aortic stenosis and membranous subaortic stenosis, representing about 75 and l0 percent of all cases respectively. ... Zie: Chapter 1

  5. 57. Aortic valve replacement with sutureless valve and mitral valve repair in patient with infected aortic homograft

    Directory of Open Access Journals (Sweden)

    A. attia

    2016-07-01

    Full Text Available The approach of implanting aortic sutureless valve inside the calcific homograft is suitable in redo surgery especially if associated with mitral valve surgery. Aortic valve replacement in patients who have undergone previous aortic root replacement with an aortic homograft remains a technical challenge because of homograft degeneration and the need for a redo Bentall operation. We report a case of redo aortic valve replacement (valve in valve with a sutureless valve and mitral valve repair by miniband annuloplasty in a female patient aged 64 years old who underwent aortic valve replacement with homograft 14 years ago and presented by sever aortic valve regurge and sever mitral valve regurge because of infective endocarditis. This technique allows rapid aortic valve replacement in a heavily calcified aortic root. It also avoids aortic valve size affection after mitral valve repair by ordinary methods especially in patients with small aortic annulus. This technique is particularly suitable in redo procedures for homograft degeneration, it avoids performing a redo Bentall operation with its known problems as well as to avoid patient prosthesis mismatch.

  6. Surgical management of a hypoplastic distal aortic arch and coarctation of aorta in a patient with Klippel-Feil syndrome, ascending aortic aneurysm and bicuspid aortic valve.

    Science.gov (United States)

    Sabol, Frantisek; Kolesar, Adrián; Toporcer, Tomás; Bajmoczi, Milan

    2014-10-01

    Klippel-Feil syndrome has been associated with cardiovascular malformations, but only 3 cases have been reported to be associated with aortic coarctation and surgical management is not defined. A 51-year old woman with Klippel-Feil syndrome associated with an aneurysm of the ascending aorta, hypoplastic aortic arch and aortic coarctation at the level of the left subclavian artery presented with shortness of breath 2 years after diagnosis. Imaging identified interim development of a 7.2-cm aneurysm at the level of the aortic coarctation. She underwent surgical repair with a Dacron interposition graft under hypothermic circulatory arrest. She continues to do well 18 months following repair.

  7. Endovascular treatment of thoracic aortic diseases

    Directory of Open Access Journals (Sweden)

    Davidović Lazar

    2013-01-01

    Full Text Available Bacground/Aim. Endovascular treatment of thoracic aortic diseases is an adequate alternative to open surgery. This method was firstly performed in Serbia in 2004, while routine usage started in 2007. Aim of this study was to analyse initial experience in endovacular treatment of thoracic aortic diseses of three main vascular hospitals in Belgrade - Clinic for Vascular and Endovascular Surgery of the Clinical Center of Serbia, Clinic for Vascular Surgery of the Military Medical Academy, and Clinic for Vascular Surgery of the Institute for Cardiovascular Diseases “Dedinje”. Methods. Between March 2004. and November 2010. 41 patients were treated in these three hospitals due to different diseases of the thoracic aorta. A total of 21 patients had degenerative atherosclerotic aneurysm, 6 patients had penetrating aortic ulcer, 6 had posttraumatic aneurysm, 4 patients had ruptured thoracic aortic aneurysm, 1 had false anastomotic aneurysm after open repair, and 3 patients had dissected thoracic aneurysm of the thoracoabdominal aorta. In 15 cases the endovascular procedure was performed as a part of the hybrid procedure, after carotidsubclavian bypass in 4 patients and subclavian artery transposition in 1 patient due to the short aneurysmatic neck; in 2 patients iliac conduit was used due to hypoplastic or stenotic iliac artery; in 5 patients previous reconstruction of abdominal aorta was performed; in 1 patient complete debranching of the aortic arch, and in 2 patients visceral abdominal debranching were performed. Results. The intrahospital mortality rate (30 days was 7.26% (3 patients with ruptured thoracic aneurysms died. Endoleak type II in the first control exam was revealed in 3 patients (7. 26%. The patients were followed up in a period of 1-72 months, on average 29 months. The most devastating complication during a followup period was aortoesofageal fistula in 1 patient a year after the treatment of posttraumatic aneurysm. Conversion was

  8. VENTRICULAR SEPTAL DEFECT ASSOCIATED WITH AORTIC VALVE PROLAPSE IN CHINESE CHILDREN——A PROSPECTIVE ASCENDING AORTOGRAM STUDY OF 550 PATIENTS

    Institute of Scientific and Technical Information of China (English)

    朱铭; 黄廉溪

    1993-01-01

    From April 1985 to April 1991, ascending aortograms were peformed in 550consecutive children with I/SD. The locations of VSD were subpulmonary in 121,perimembranous in 420, and muscular in 9 cases. Seventy-eight cases (14.2%) were associ-ated with aortic valve prolapse (male 57,female 21), 38 without AR and 40 with AR,which occured in 54 (44.6%)subpulmonary VSD, 24 (5.7%) in perimembranous VSD.Most of the VSD with aortic prolapse were functionally small. Ascending aortogram andleft ventriculogram (RAO view) can demonstrate aortic prolapse.

  9. Input and Second Language Acquisition

    Institute of Scientific and Technical Information of China (English)

    周笑盈

    2011-01-01

    The behaviorist, the mentalist and the interactionist have different emphases on the role input in Second Language Acquisition. In order to protrude the importance of second language teaching, it is indispensible to discuss the characteristics of input and to explore its effects.

  10. Input in Second Language Acquisition.

    Science.gov (United States)

    Gass, Susan M., Ed.; Madden, Carolyn G., Ed.

    This collection of conference papers includes: "When Does Teacher Talk Work as Input?"; "Cultural Input in Second Language Learning"; "Skilled Variation in a Kindergarten Teacher's Use of Foreigner Talk"; "Teacher-Pupil Interaction in Second Language Development"; "Foreigner Talk in the University…

  11. Inputs for L2 Acquisition.

    Science.gov (United States)

    Saleemi, Anjum P.

    1989-01-01

    Major approaches of describing or examining linguistic data from a potential target language (input) are analyzed for adequacy in addressing the concerns of second language learning theory. Suggestions are made for making the best of these varied concepts of input and for reformulation of a unified concept. (MSE)

  12. Six axis force feedback input device

    Science.gov (United States)

    Ohm, Timothy (Inventor)

    1998-01-01

    The present invention is a low friction, low inertia, six-axis force feedback input device comprising an arm with double-jointed, tendon-driven revolute joints, a decoupled tendon-driven wrist, and a base with encoders and motors. The input device functions as a master robot manipulator of a microsurgical teleoperated robot system including a slave robot manipulator coupled to an amplifier chassis, which is coupled to a control chassis, which is coupled to a workstation with a graphical user interface. The amplifier chassis is coupled to the motors of the master robot manipulator and the control chassis is coupled to the encoders of the master robot manipulator. A force feedback can be applied to the input device and can be generated from the slave robot to enable a user to operate the slave robot via the input device without physically viewing the slave robot. Also, the force feedback can be generated from the workstation to represent fictitious forces to constrain the input device's control of the slave robot to be within imaginary predetermined boundaries.

  13. Effect of transcatheter aortic valve implantation on intraoperative left ventricular end-diastolic pressure.

    Science.gov (United States)

    Toyota, Kosaku; Ota, Takashi; Nagamine, Katsutoshi; Koide, Yasuhiro; Nomura, Takeshi; Yamanaka, Futoshi; Shishido, Koki; Tanaka, Masashi; Saito, Shigeru

    2016-12-01

    Transcatheter aortic valve implantation (TAVI) for patients with aortic stenosis is a less invasive alternative to surgical aortic valve replacement. Despite this, careful anesthetic management, especially strict control of blood pressure and fluid management, is necessary. During TAVI, normalization of left ventricular afterload due to aortic balloon valvuloplasty and prosthetic valve deployment is expected to result in rapid improvement of systolic function and consequent improvement in diastolic function. However, the early effect of TAVI on left ventricular diastolic function is less clear. We hypothesized that TAVI induces a rapid decrease in left ventricular end-diastolic pressure (LVEDP) after valve deployment. This retrospective observational study included 71 patients who had undergone TAVI using the transfemoral approach with a balloon-expandable valve under general anesthesia. Intraoperative LVEDP was measured using an intracardiac catheter. The severity of residual aortic regurgitation (AR) was assessed using the Sellers criteria. The mean (SD) LVEDP was 17.8 (5.3) mmHg just before TAVI and increased significantly to 27.3 (8.2) mmHg immediately after prosthetic valve deployment (p < 0.0001). The change in LVEDP was 8.7 (8.6) mmHg in patients with low residual AR (Sellers ≤1) and 11.0 (7.1) mmHg in those with high residual AR (Sellers ≥2); however, this difference was not significant. No correlation was found between the LVEDP change and intraoperative fluid balance. In conclusion, LVEDP increased significantly in the early period after valve deployment during TAVI, regardless of residual AR severity. It was suggested that the tolerability of fluid load could be reduced at that time.

  14. Intramural aortic hematomas; Intramurale Haematome der Aorta

    Energy Technology Data Exchange (ETDEWEB)

    Raab, B.W.; Vosshenrich, R.; Fischer, U.; Funke, M.; Grabbe, E. [Goettingen Univ. (Germany). Abt. fuer Roentgendiagnostik

    2001-08-01

    Intramural hematomas (IMH) are regarded as a hemorrhage into the aortic wall. In general a traumatic form can be differentiated from a spontaneous non-traumatic. There is a predisposition of IMH with arterial hypertension and mesoectodermal dysplastic syndromes. The diagnosis is established with the clinical presentation in combination with the findings of different imaging modalities. Acute and subacute discomfort associated with a tendency of collaps are considered as typical presenting complaints. A semicircular or concentric thickening of the aortic wall with the absence of blood flow or a dissection membran are typical findings in transesophageal echocardiography, computed tomography and magnetic resonance tomography. From a differential diagnostic point of view a distinction from atherosclerotic wall changes, intraluminal thrombi and inflammatory aortic diseases is essential. The IMH is considered as an early presentation of aortic dissection, put into and treated according to the Stanford classification. In the course of natural history an IMH can disappear, rupture or progress into a classic aortic dissection. (orig.) [German] Das intramurale Haematom (IMH) ist eine Einblutung in die Aortenwand. Grundsaetzlich kann zwischen traumatischer Genese und einer atraumatischen spontanen Form unterschieden werden. Praedisponierend sind arterielle Hypertension und mesoektodermale Dysplasiesyndrome. Die Diagnose ergibt sich aus der Klinik und den Befunden in den bildgebenden Verfahren. Zu den klinischen Symptomen zaehlen akut oder subakut auftretende Schmerzen, assoziiert mit einer Kollapsneigung. Typische Befunde in der transoesophagealen Echokardiographie, der Computer- oder der Magnetresonanztomographie sind eine halbmondfoermige oder konzentrische Wandverdickung der Aorta ohne Nachweis von Blutfluss oder einer Dissektionsmembran mit Dichtewerten bzw. Signalintensitaeten in Abhaengigkeit vom Alter der Einblutung. Differenzialdiagnostisch ist eine Abgrenzung

  15. Reconstructive surgery of the aortic valve

    Directory of Open Access Journals (Sweden)

    Mendonça José Teles de

    2003-01-01

    Full Text Available OBJECTIVE: Lacking an ideal valve substitute and motivated by the good results of mitral valve repair since 1990, we faced with determination aortic valve reconstruction surgery. The objective of this paper is to show our experience with this procedure. METHOD: Between January of 1990 and December of 2001; 136 aortic valve repair surgeries were performed. Seventy-five (55.1% of the patients were female and the ages ranged from 4 to 70 years (mean 23.3 ± 1.2 years. Every patient had rheumatic valve disease and insufficiency was the most prevalent type (108 patients - 79.4%, followed by double aortic lesion in 16 (11.7% patients and stenosis in 12 (8.8%. The surgical techniques used were: subcommissural annuloplasty in 74 (54.4% patients, commissurotomy in 38 (27.9%, cusp extension with pericardium in 17 (12.5%, substitution of one cusp in 2 (1.4%, cusp suspension by annuloplasty in 37 (27.2% and Valsalva sinus remodeling in 27 (19.8%. The surgery exclusively involved the aortic valve in 57 (41.9% patients and was associated in 79 (mitral valve replacement in 12, mitral repair in 65, coronary artery bypass grafting in 1 and pulmonary commissurotomy in 1. RESULTS: Hospital mortality was 2.2% and 22 (16.2% patients underwent a new surgery during the follow-up period (57.7 ± 3.5 months. CONCLUSIONS: Aortic valve repair is a safe surgical procedure that can be used in an increasing number of patients with promising results.

  16. Limitation of imaging in identifying iatrogenic aortic coarctation following thoracic endovascular aortic repair.

    Science.gov (United States)

    Thakkar, Rajiv N; Thomaier, Lauren; Qazi, Umair; Verde, Franco; Malas, Mahmoud B

    2015-04-01

    A 21-year-old male suffered blunt trauma from a motor vehicle accident causing thoracic aorta tear. The smallest available stent graft was deployed. Definitive repair was later performed using a 22 × 22 × 116 mm Talent Thoracic Stent Graft. The postoperative course was uneventful. Seventeen months later, he presented with dizziness, chest pain, acute renal failure, malignant hypertension, and troponin elevation. Computed tomography (CT) angiogram and transesophageal echocardiogram did not reveal any dissection, stent stenosis or collapse. Cardiac catheterization showed normal coronary arteries but a 117 mm Hg gradient across the stent graft. Iatrogenic coarctation of the aorta was confirmed with a second measurement during arch angiogram. A Palmaz stent was deployed over the distal end of the previous stent graft with complete resolution of symptoms and gradual normalization of kidney function. This case report demonstrates a need for wider availability and selecting appropriate stent graft in treating traumatic aortic injuries in young patients. It is the first case report of the inability of current imaging modalities in confirming stent collapse. Pressure gradient is a useful tool in confirming stent collapse when clinical scenario does not match CT findings.

  17. Impact of Aortic Valve Replacement on Left Ventricular Remodeling in Patients with Severe Aortic Stenosis and Severe Left Ventricular Dysfunction

    Directory of Open Access Journals (Sweden)

    Abderrahmane Bakkali

    2016-12-01

    Full Text Available Objective: The aim of this study was to evaluate the effect of aortic valve replacement on left ventricular function and remodeling among patients with severe aortic stenosis and severe left ventricular dysfunction. Methods: In this retrospective bicentric study extended over a 15-year period, 61 consecutive patients underwent isolated AVR for severe AS associated to reduced LV function. The mean age was 58.21 ± 12.50 years and 83.60 % were men. 70.50% of patients were in class III or IV NYHA. The mean left ventricular ejection fraction (LVEF was 32.9 ± 5.6.The mean LVEDD and LVESD were respectively 63.6 ± 9.2 and 50.2 ± 8.8 mm. The mean calculated logistic EuroScore was 12.2 ±4.5. Results: The hospital mortality was 11.5%. Morbidity was marked mainly by low output syndrome in 40.8% of cases. After a median follow-up of 38 months we have recorded 3 deaths. Almost all survivors were in class I and II of NYHA. The mean LV end-diastolic and end-systolic diameters decreased significantly at late postoperative stage. The mean LV ejection fraction increased significantly from 32.9 ± 5.6 to 38.2 ± 9.3 and to 50.3 ± 9.6 in early and late postoperative stages, respectively. Multivariate linear regression analysis found that increased early postoperative LVEF (β= 0.44, 95% CI [0.14; 0.75], p=0.006 and low mean transprosthesis gradient (β=-0.72, 95% CI [-1.42; -0.02], p= 0.04 were the independent predictors of left ventricular systolic function recovery. Conclusion: Patients with aortic valve stenosis and impaired LV systolic function benefited from AVR as regard improvement of LV function parameters and regression of the LV diameters .This improvement depends mainly on early postoperative LVEF and mean transprosthesis gradient.

  18. Imaging Aortic Regurgitation: The Incremental Benefit of Speckle Tracking Echocardiography

    Science.gov (United States)

    Garg, Pankaj; Yassin, Firas; Leischik, Roman

    2015-01-01

    Aortic regurgitation (AR) affects global left ventricular mechanics. However, limited literature is available on how it may affect regional longitudinal strain. We present a case where severe AR jet is thrashing the anterior-septal wall and reducing its overall longitudinal performance most likely secondary to increased wall shear stress in diastole. This new insight into patho-physiological process using deformation study may have supplementary impact in decision making for surgical intervention. Transthoracic echocardiography is the primary imaging modality for the assessment of AR as it offers evaluation of severity of AR, aetiology of AR, left ventricular (LV) dilatation, LV systolic function, left ventricular mass, diastolic function and global strain. This case highlights the regional disturbances in longitudinal strain in eccentric AR. PMID:27006711

  19. Programmable Input for Nanomagnetic Logic Devices

    Directory of Open Access Journals (Sweden)

    Schmitt-Landsiedel D.

    2013-01-01

    Full Text Available A programmable magnetic input, based on the magnetic interaction of a soft and hard magnetic layer is presented for the first time. Therefore, a single-domain Co/Pt nanomagnet is placed on top of one end of a permalloy bar, separated by a thin dielectric layer. The permalloy bar of the introduced input structure is magnetized by weak easy-axis in-plane fields. Acting like a ’magnetic amplifier’, the generated fringing fields of the permalloy pole are strong enough to control the magnetization of the superimposed Co/Pt nanomagnets, which have high crystalline perpendicular magnetic anisotropy. This magnetostatic interaction results in a shift of the hysteresis curve of the Co/Pt nanomagnet, measured by magneto-optical Kerr microscopy. The Co/Pt nanomagnet is fixed by the fringing field of the permalloy and thereby not affected by the magnetic power clock of the Nanomagnetic Logic system. MFM measurements verify the functionality of the programmable magnetic input structure. The fringing fields are extracted from micromagnetic simulations and are in good agreement with experimental results. The introduced input structure enables switching the logic functionality of the majority gate from NAND to NOR during runtime, offering programmable Nanomagnetic Logic.

  20. Inhibitory role of Notch1 in calcific aortic valve disease.

    Directory of Open Access Journals (Sweden)

    Asha Acharya

    Full Text Available Aortic valve calcification is the most common form of valvular heart disease, but the mechanisms of calcific aortic valve disease (CAVD are unknown. NOTCH1 mutations are associated with aortic valve malformations and adult-onset calcification in families with inherited disease. The Notch signaling pathway is critical for multiple cell differentiation processes, but its role in the development of CAVD is not well understood. The aim of this study was to investigate the molecular changes that occur with inhibition of Notch signaling in the aortic valve. Notch signaling pathway members are expressed in adult aortic valve cusps, and examination of diseased human aortic valves revealed decreased expression of NOTCH1 in areas of calcium deposition. To identify downstream mediators of Notch1, we examined gene expression changes that occur with chemical inhibition of Notch signaling in rat aortic valve interstitial cells (AVICs. We found significant downregulation of Sox9 along with several cartilage-specific genes that were direct targets of the transcription factor, Sox9. Loss of Sox9 expression has been published to be associated with aortic valve calcification. Utilizing an in vitro porcine aortic valve calcification model system, inhibition of Notch activity resulted in accelerated calcification while stimulation of Notch signaling attenuated the calcific process. Finally, the addition of Sox9 was able to prevent the calcification of porcine AVICs that occurs with Notch inhibition. In conclusion, loss of Notch signaling contributes to aortic valve calcification via a Sox9-dependent mechanism.

  1. Relation of thoracic aortic and aortic valve calcium to coronary artery calcium and risk assessment.

    Science.gov (United States)

    Wong, Nathan D; Sciammarella, Maria; Arad, Yadon; Miranda-Peats, Romalisa; Polk, Donna; Hachamovich, Rory; Friedman, John; Hayes, Sean; Daniell, Anthony; Berman, Daniel S

    2003-10-15

    Aortic calcium, aortic valve calcium (AVC), and coronary artery calcium (CAC) have been associated with cardiovascular event risk. We examined the prevalence of thoracic aortic calcium (TAC) and AVC in relation to the presence and extent of CAC, cardiovascular risk factors, and estimated risk of coronary heart disease (CHD). In 2,740 persons without known CHD aged 20 to 79 years, CAC was assessed by electron beam- or multidetector-computed tomography. We determined the prevalence of TAC and AVC in relation to CAC, CHD risk factors, and predicted 10-year risk of CHD. A close correspondence of TAC and AVC was observed with CAC. TAC and AVC increased with age; by the eighth decade of life, the prevalence of TAC was similar to that of CAC (>80%), and 36% of men and 24% of women had AVC. Age, male gender, and low-density lipoprotein cholesterol were directly related to the likelihood of CAC, TAC, and AVC; higher diastolic blood pressure and cigarette smoking additionally predicted CAC. Body mass index and higher systolic and lower diastolic blood pressures were also related to TAC, and higher body mass index and lower diastolic blood pressure were related to AVC. Calculated risk of CHD increased with the presence of AVC and TAC across levels of CAC. TAC and AVC provided incremental value over CAC in association with the 10-year calculated risk of CHD. If longitudinal studies show an incremental value of aortic and aortic valve calcium over that of CAC for prediction of cardiovascular events, future guidelines for risk assessment incorporating CAC assessment may additionally incorporate the measurement of aortic and/or aortic valve calcium.

  2. Input management of production systems.

    Science.gov (United States)

    Odum, E P

    1989-01-13

    Nonpoint sources of pollution, which are largely responsible for stressing regional and global life-supporting atmosphere, soil, and water, can only be reduced (and ultimately controlled) by input management that involves increasing the efficiency of production systems and reducing the inputs of environmentally damaging materials. Input management requires a major change, an about-face, in the approach to management of agriculture, power plants, and industries because the focus is on waste reduction and recycling rather than on waste disposal. For large-scale ecosystem-level situations a top-down hierarchical approach is suggested and illustrated by recent research in agroecology and landscape ecology.

  3. The Relationship Between Aortic Root Size and Hypertension: An Unsolved Conundrum.

    Science.gov (United States)

    Mulè, Giuseppe; Nardi, Emilio; Morreale, Massimiliano; Castiglia, Antonella; Geraci, Giulio; Altieri, Dario; Cacciatore, Valentina; Schillaci, Margherita; Vaccaro, Francesco; Cottone, Santina

    2016-11-22

    Thoracic aortic aneurysms rupture and dissection are among the most devastating vascular diseases, being characterized by elevated mortality, despite improvements in diagnostic imaging and surgical techniques.An increased aortic root diameter (ARD) represents the main risk factor for thoracic aortic dissection and rupture and for aortic valve regurgitation.Even though arterial hypertension is commonly regarded as a predisposing condition for the development of thoracic aorta aneurysms, the role of blood pressure (BP) as determinant of aortic root enlargement is still controversial. The use of different methods for indexation of ARD may have in part contributed to the heterogeneous findings obtained in the investigations exploring the relationships between ARD and BP. Indeed, the best methods for ARD indexation, as well as the normal values of aortic root size, are still a matter of debate.Several non-hemodynamic factors influence ARD, including age, gender, and anthropometric variables, such as height, weight and their derivatives body surface area (BSA) and body mass index. Of these factors, anthropometric variables have the greatest impact.Several studies documented an association between ARD enlargement, assessed by echocardiography, and some indices of hypertensive target organ damage such as left ventricular hypertrophy, diastolic dysfunction, and carotid intima-media thickening. Recently, we found that ARD, expressed either as absolute values or normalized for BSA (ARD/BSA) or height (ARD/H), was significantly greater in hypertensive subjects with chronic kidney disease (CKD) when compared to their counterparts with normal renal function. Moreover, at univariate analyses estimated glomerular filtration rate (eGFR) showed significant inverse correlations with ARD not indexed and with ARD/BSA and ARD/H. Taking into account the effect of age, sex, duration of hypertension and other potentially confounding factors, in multiple regression analyses, only the

  4. Effect of Selenium Supplementation on Redox Status of the Aortic Wall in Young Spontaneously Hypertensive Rats.

    Science.gov (United States)

    Ruseva, Boryana; Atanasova, Milena; Tsvetkova, Reni; Betova, Tatyana; Mollova, Margarita; Alexandrova, Margarita; Laleva, Pavlina; Dimitrova, Aneliya

    2015-01-01

    Selenium (Se) is an exogenous antioxidant that performs its function via the expression of selenoproteins. The aim of this study was to explore the effect of varying Se intake on the redox status of the aortic wall in young spontaneously hypertensive rats (SHR). Sixteen male Wistar Kyoto (WKY) rats and nineteen male SHR, 16-week-old, were tested after being given diets with different Se content for eight weeks. They were divided into 4 groups: control groups of WKY NSe and SHR NSe on an adequate Se diet and groups of WKY HSe and SHR HSe that received Se supplementation. The Se nutritional status was assessed by measuring whole blood glutathione peroxidase-1 (GPx-1) activity. Serum concentration of lipid hydroperoxides and serum level of antibodies against advanced glycation end products (anti-AGEs abs) were determined. Expression of GPx-1 and endothelial nitric oxide synthase (eNOS) were examined in aortic wall. Se supplementation significantly increased GPx-1 activity of whole blood and in the aortas of WKY and SHR. Decreased lipid peroxidation level, eNOS-3 expression in the aortic wall, and serum level of anti-AGEs abs were found in SHR HSe compared with SHR NSe. In conclusion, Se supplementation improved the redox status of the aortic wall in young SHR.

  5. Effect of Selenium Supplementation on Redox Status of the Aortic Wall in Young Spontaneously Hypertensive Rats

    Directory of Open Access Journals (Sweden)

    Boryana Ruseva

    2015-01-01

    Full Text Available Selenium (Se is an exogenous antioxidant that performs its function via the expression of selenoproteins. The aim of this study was to explore the effect of varying Se intake on the redox status of the aortic wall in young spontaneously hypertensive rats (SHR. Sixteen male Wistar Kyoto (WKY rats and nineteen male SHR, 16-week-old, were tested after being given diets with different Se content for eight weeks. They were divided into 4 groups: control groups of WKY NSe and SHR NSe on an adequate Se diet and groups of WKY HSe and SHR HSe that received Se supplementation. The Se nutritional status was assessed by measuring whole blood glutathione peroxidase-1 (GPx-1 activity. Serum concentration of lipid hydroperoxides and serum level of antibodies against advanced glycation end products (anti-AGEs abs were determined. Expression of GPx-1 and endothelial nitric oxide synthase (eNOS were examined in aortic wall. Se supplementation significantly increased GPx-1 activity of whole blood and in the aortas of WKY and SHR. Decreased lipid peroxidation level, eNOS-3 expression in the aortic wall, and serum level of anti-AGEs abs were found in SHR HSe compared with SHR NSe. In conclusion, Se supplementation improved the redox status of the aortic wall in young SHR.

  6. Evaluation of Biaxial Mechanical Properties of Aortic Media Based on the Lamellar Microstructure

    Directory of Open Access Journals (Sweden)

    Hadi Taghizadeh

    2015-01-01

    Full Text Available Evaluation of the mechanical properties of arterial wall components is necessary for establishing a precise mechanical model applicable in various physiological and pathological conditions, such as remodeling. In this contribution, a new approach for the evaluation of the mechanical properties of aortic media accounting for the lamellar structure is proposed. We assumed aortic media to be composed of two sets of concentric layers, namely sheets of elastin (Layer I and interstitial layers composed of mostly collagen bundles, fine elastic fibers and smooth muscle cells (Layer II. Biaxial mechanical tests were carried out on human thoracic aortic samples, and histological staining was performed to distinguish wall lamellae for determining the dimensions of the layers. A neo-Hookean strain energy function (SEF for Layer I and a four-parameter exponential SEF for Layer II were allocated. Nonlinear regression was used to find the material parameters of the proposed microstructural model based on experimental data. The non-linear behavior of media layers confirmed the higher contribution of elastic tissue in lower strains and the gradual engagement of collagen fibers. The resulting model determines the nonlinear anisotropic behavior of aortic media through the lamellar microstructure and can be assistive in the study of wall remodeling due to alterations in lamellar structure during pathological conditions and aging.

  7. Valve Replacement with a Sutureless Aortic Prosthesis in a Patient with Concomitant Mitral Valve Disease and Severe Aortic Root Calcification.

    Science.gov (United States)

    Lio, Antonio; Scafuri, Antonio; Nicolò, Francesca; Chiariello, Luigi

    2016-04-01

    Aortic valve replacement with concomitant mitral valve surgery in the presence of severe aortic root calcification is technically difficult, with long cardiopulmonary bypass and aortic cross-clamp times. We performed sutureless aortic valve replacement and mitral valve annuloplasty in a 68-year-old man who had severe aortic stenosis and moderate-to-severe mitral regurgitation. Intraoperatively, we found severe calcification of the aortic root. We approached the aortic valve through a transverse aortotomy, performed in a higher position than usual, and we replaced the valve with a Sorin Perceval S sutureless prosthesis. In addition, we performed mitral annuloplasty with use of an open rigid ring. The aortic cross-clamp time was 63 minutes, and the cardiopulmonary bypass time was 83 minutes. No paravalvular leakage of the aortic prosthesis was detected 30 days postoperatively. Our case shows that the Perceval S sutureless bioprosthesis can be safely implanted in patients with aortic root calcification, even when mitral valve disease needs surgical correction.

  8. Thoracic aortic aneurysm: reading the enemy's playbook.

    Science.gov (United States)

    Elefteriades, John A

    2008-05-01

    The vast database of the Yale Center for Thoracic Aortic Disease--which includes information on 3000 patients with thoracic aortic aneurysm or dissection, with 9000 catalogued images and 9000 patient-years of follow-up--has, over the last decade, permitted multiple glimpses into the "playbook" of this virulent disease. Understanding the precise behavioral features of thoracic aortic aneurysm and dissection permits us more effectively to combat this disease. In this monograph, we will first review certain fundamentals--in terms of anatomy, nomenclature, imaging, diagnosis, medical, surgical, and stent treatment. After reviewing these fundamentals, we will proceed with a detailed exploration of lessons learned by peering into the operational playbook of thoracic aortic aneurysm and dissection. Among the glimpses afforded in the behavioral playbook of this disease are the following: 1 Thoracic aortic aneurysm, while lethal, is indolent. Mortality usually does not occur until after years of growth. 2 The aneurysmal ascending thoracic aorta grows slowly: about 0.1 cm per year (the descending aorta grows somewhat faster). 3 Over a patient's lifetime, "hinge points" at which the likelihood of rupture or dissection skyrockets are seen at 5.5 cm for the ascending and 6.5 cm for the descending aorta. Intervening at 5 cm diameter for the ascending and 6 cm for the descending prevents most adverse events. 4 Symptomatic aneurysms require resection regardless of size. 5 The yearly rate of rupture, dissection, or death is 14.1% for a patient with a thoracic aorta of 6 cm diameter. 6 The mechanical properties of the aorta deteriorate markedly at 6 cm diameter (distensibility falls, and wall stress rises)--a finding that "dovetails" perfectly with observations of the clinical behavior of the thoracic aorta. 7 Thoracic aortic aneurysm and dissection are largely inherited diseases, with a predominantly autosomal-dominant pattern. The specific genetics are being elucidated at the

  9. The Advanced LIGO Input Optics

    CERN Document Server

    Mueller, Chris; Ciani, Giacomo; DeRosa, Ryan; Effler, Anamaria; Feldbaum, David; Frolov, Valery; Fulda, Paul; Gleason, Joseph; Heintze, Matthew; King, Eleanor; Kokeyama, Keiko; Korth, William; Martin, Rodica; Mullavey, Adam; Poeld, Jan; Quetschke, Volker; Reitze, David; Tanner, David; Williams, Luke; Mueller, Guido

    2016-01-01

    The Advanced LIGO gravitational wave detectors are nearing their design sensitivity and should begin taking meaningful astrophysical data in the fall of 2015. These resonant optical interferometers will have unprecedented sensitivity to the strains caused by passing gravitational waves. The input optics play a significant part in allowing these devices to reach such sensitivities. Residing between the pre-stabilized laser and the main interferometer, the input optics is tasked with preparing the laser beam for interferometry at the sub-attometer level while operating at continuous wave input power levels ranging from 100 mW to 150 W. These extreme operating conditions required every major component to be custom designed. These designs draw heavily on the experience and understanding gained during the operation of Initial LIGO and Enhanced LIGO. In this article we report on how the components of the input optics were designed to meet their stringent requirements and present measurements showing how well they h...

  10. Aortic tear and dissection related to connective tissues abnormalities resembling Marfan syndrome in a Great Dane.

    Science.gov (United States)

    Lenz, Jennifer A; Bach, Jonathan F; Bell, Cynthia M; Stepien, Rebecca L

    2015-06-01

    Aortic tears and acute aortic dissection are rarely reported in dogs. This report describes a case of aortic dissection and probable sinus of Valsalva rupture in a young Great Dane with associated histopathologic findings suggestive of a connective tissue abnormality.

  11. Acute aortic occlusion as an unusual embolic complication of cardiac myxoma

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian; DUAN Zhi-quan; WANG Chuan-jiang; SONG Qing-bin; LUO Ying-wei; XIN Shi-jie

    2006-01-01

    @@ Acute aortic occlusion is an infrequent but dangerous vascular emergency with a mortality rate of 50%,1 resulting from aortic saddle embolus, thrombosis of an atherosclerotic abdominal aorta, or sudden thrombosis of a small abdominal aortic aneurysm.

  12. Nonlinear input-output systems

    Science.gov (United States)

    Hunt, L. R.; Luksic, Mladen; Su, Renjeng

    1987-01-01

    Necessary and sufficient conditions that the nonlinear system dot-x = f(x) + ug(x) and y = h(x) be locally feedback equivalent to the controllable linear system dot-xi = A xi + bv and y = C xi having linear output are found. Only the single input and single output case is considered, however, the results generalize to multi-input and multi-output systems.

  13. Enlargement of the aortic annulus during aortic valve replacement: a review.

    Science.gov (United States)

    Bortolotti, Uberto; Celiento, Michele; Milano, Aldo D

    2014-01-01

    The main goal of aortic valve replacement (AVR) is to obtain relief from the fixed left ventricular (LV) obstruction by replacing the aortic valve with a prosthesis, either mechanical or biological, of adequate size. Most currently available prostheses provide satisfactory hemodynamic performance, but small-sized prostheses may be associated with high transvalvular gradients and suboptimal effective orifice area that result in prosthesis-patient mismatch (PPM), and thus are far from ideal for use in young, active patients. The avoidance of PPM is advisable as it has been repeatedly associated with increased mortality, decreased exercise tolerance and an impaired regression of LV hypertrophy after AVR for severe aortic stenosis. Enlargement of the aortic annulus (EAA) has proved to be a valuable method to prevent PPM in the presence of a diminutive aortic root. This review outlines the various techniques described for EAA, presenting technical details, long-term results and major procedure-related complications, and discussing the current role of EAA in patients requiring AVR.

  14. Endovascular treatment of late thoracic aortic aneurysms after surgical repair of congenital aortic coarctation in childhood.

    Directory of Open Access Journals (Sweden)

    Robert Juszkat

    Full Text Available BACKGROUND: In some patients, local surgery-related complications are diagnosed many years after surgery for aortic coarctation. The purposes of this study were: (1 to systematically evaluate asymptomatic adults after Dacron patch repair in childhood, (2 to estimate the formation rate of secondary thoracic aortic aneurysms (TAAs and (3 to assess outcomes after intravascular treatment for TAAs. METHODS: This study involved 37 asymptomatic patients (26 female and 11 male who underwent surgical repair of aortic coarctation in the childhood. After they had reached adolescence, patients with secondary TAAs were referred to endovascular repair. RESULTS: Follow-up studies revealed TAA in seven cases (19% (including six with the gothic type of the aortic arch and mild recoarctation in other six (16%. Six of the TAA patients were treated with stentgrafts, but one refused to undergo an endovascular procedure. In three cases, stengrafts covered the left subclavian artery (LSA, in another the graft was implanted distally to the LSA. In two individuals, elective hybrid procedures were performed with surgical bypass to the supraaortic arteries followed by stengraft implantation. All subjects survived the secondary procedures. One patient developed type Ia endoleak after stentgraft implantation that was eventually treated with a debranching procedure. CONCLUSIONS: The long-term course of clinically asymptomatic patients after coarctation patch repair is not uncommonly complicated by formation of TAAs (particularly in individuals with the gothic pattern of the aortic arch that can be treated effectively with stentgrafts. However, in some patients hybrid procedures may be necessary.

  15. Fluid dynamics of aortic root dilation in Marfan syndrome

    CERN Document Server

    Querzoli, Giorgio; Espa, Stefania; Costantini, Martina; Sorgini, Francesca

    2014-01-01

    Aortic root dilation and propensity to dissection are typical manifestations of the Marfan Syndrome (MS), a genetic defect leading to the degeneration of the elastic fibres. Dilation affects the structure of the flow and, in turn, altered flow may play a role in vessel dilation, generation of aneurysms, and dissection. The aim of the present work is the investigation in-vitro of the fluid dynamic modifications occurring as a consequence of the morphological changes typically induced in the aortic root by MS. A mock-loop reproducing the left ventricle outflow tract and the aortic root was used to measure time resolved velocity maps on a longitudinal symmetry plane of the aortic root. Two dilated model aortas, designed to resemble morphological characteristics typically observed in MS patients, have been compared to a reference, healthy geometry. The aortic model was designed to quantitatively reproduce the change of aortic distensibility caused by MS. Results demonstrate that vorticity released from the valve ...

  16. Small aortic valve annulus in children with fixed subaortic stenosis.

    Science.gov (United States)

    Thilenius, O G; Campbell, D; Bharati, S; Lev, M; Arcilla, R A

    1989-01-01

    Twenty-one hearts with fixed subaortic stenosis (FSAS) were examined pathologically. Thirty children with no hemodynamically significant heart disease, 31 children with valvar aortic stenosis, and 25 children with FSAS were studied by echo- and angiocardiography. The following conclusions were drawn: (1) Patients with FSAS often have abnormal aortic valve leaflets as well as small aortic valve annulus. (2) A small aortic annulus/descending aorta ratio is probably present at birth, and may decrease with increasing age. (3) In some patients with FSAS the aortic valve annulus is too small for simple resection of the fibroelastic tissue. A Konno operation is needed for these patients. (4) M-mode echocardiography has not been useful in identifying abnormally small aortic valve annulus in FSAS patients.

  17. Aortic valve replacement in familial hypercholesterolemia: not an ordinary procedure.

    Science.gov (United States)

    Muretti, Mirko; Massi, Francesco; Coradduzza, Enrico; Portoghese, Michele

    2015-04-28

    Familial hypercholesterolemia is an inherited disorder with incidences of approximately 1:500 and 1:1,000,000 in heterozygous and homozygous form respectively. Affected patients usually show early coronary artery disease and severe aortic root calcification, despite optimization of therapy. We report a case of a 64-year-old woman affected by heterozygous familial hypercholesterolemia which presented dyspnea and anginal symptoms due to a severely calcified aortic root causing valve stenosis and narrowed sinotubular junction. Aortic valve replacement and aortic root enlargement were performed using the Manougian procedure. Even for experiences surgeons, this surgery could prove challenging for this group of patients due to aggressive degenerative tissue calcification of the aortic root, which often presents an extremely calcified aortic valve with a small annulus associated to a narrowed sinotubular junction.

  18. Implantation of the CoreValve percutaneous aortic valve.

    Science.gov (United States)

    Lamarche, Yoan; Cartier, Raymond; Denault, André Y; Basmadjian, Arsène; Berry, Colin; Laborde, Jean-Claude; Bonan, Raoul

    2007-01-01

    Surgical aortic valve replacement is the only recommended treatment for significant aortic valve stenosis. Percutaneous aortic valve replacement appears to be a novel option for high-risk patients. We report the implantation of the ReValving system (CoreValve, Paris, France) in a 64-year-old woman who was refused aortic valve replacement surgery for critical aortic stenosis and left ventricular dysfunction because of severe pulmonary fibrosis. After anesthesia, the patient was put on femorofemoral cardiopulmonary bypass, and underwent a balloon valvuloplasty with subsequent retrograde aortic valve replacement by the ReValving system. Transesophageal echocardiographic monitoring of the patient's hemodynamics showed immediate improvements of the valvular area and left ventricular ejection fraction and only traces of paravalvular leaks. The patient was easily weaned from ventilation and resumed activity soon after the surgery. A multidisciplinary approach is presently necessary to offer a reliable and safe procedure.

  19. Adjusting parameters of aortic valve stenosis severity by body size

    DEFF Research Database (Denmark)

    Minners, Jan; Gohlke-Baerwolf, Christa; Kaufmann, Beat A

    2014-01-01

    BACKGROUND: Adjustment of cardiac dimensions by measures of body size appears intuitively convincing and in patients with aortic stenosis, aortic valve area (AVA) is commonly adjusted by body surface area (BSA). However, there is little evidence to support such an approach. OBJECTIVE: To identify...... the adequate measure of body size for the adjustment of aortic stenosis severity. METHODS: Parameters of aortic stenosis severity (jet velocity, mean pressure gradient (MPG) and AVA) and measures of body size (height, weight, BSA and body mass index (BMI)) were analysed in 2843 consecutive patients with aortic...... stenosis (jet velocity ≥2.5 m/s) and related to outcomes in a second cohort of 1525 patients from the Simvastatin/Ezetimibe in Aortic Stenosis (SEAS) study. RESULTS: Whereas jet velocity and MPG were independent of body size, AVA was significantly correlated with height, weight, BSA and BMI (Pearson...

  20. Review of molecular and mechanical interactions in the aortic valve and aorta: implications for the shared pathogenesis of aortic valve disease and aortopathy.

    Science.gov (United States)

    Krishnamurthy, Varun K; Godby, Richard C; Liu, G R; Smith, J Michael; Hiratzka, Loren F; Narmoneva, Daria A; Hinton, Robert B

    2014-12-01

    Aortic valve disease (AVD) and aortopathy are associated with substantial morbidity and mortality, representing a significant cardiovascular healthcare burden worldwide. These mechanobiological structures are morphogenetically related and function in unison from embryonic development through mature adult tissue homeostasis, serving both coordinated and distinct roles. In addition to sharing common developmental origins, diseases of the aortic valve and proximal thoracic aorta often present together clinically. Current research efforts are focused on identifying etiologic factors and elucidating pathogenesis, including genetic predisposition, maladaptive cell-matrix remodeling processes, and hemodynamic and biomechanical perturbations. Here, we review the impact of these processes as they pertain to translational research efforts, emphasizing the overlapping relationship of these two disease processes. The successful application of new therapeutic strategies and novel tissue bioprostheses for AVD and/or aortopathy will require an understanding and integration of molecular and biomechanical processes for both diseases.

  1. Aortic arch blunt injury in front-seat passenger.

    Science.gov (United States)

    Türkmen, Nursel; Eren, Bülent; Aydin, Şule Akköse

    2013-10-01

    Aortic arch blunt injury has highly lethal nature. Because the physical examination findings are subtle, immediate medical evaluation is very important. The case was a 72-year-old woman. Massive haemorrhage in the left haemotorax, contusion area in the left lung and a traumatic transection of the distal aortic arch was observed during autopsy. We described intersting autopsy case of aortic arch blunt injury.

  2. Apicoaortic conduit for severe hemolytic anemia after aortic valve replacement.

    Science.gov (United States)

    Hatori, Kyohei; Ohki, Satoshi; Obayashi, Tamiyuki; Koyano, Tetsuya; Yasuhara, Kiyomitsu; Hirai, Hanako

    2015-06-01

    We describe the case of an 82-year-old woman who had undergone aortic mechanical valve replacement for aortic stenosis with a small annulus, and coronary artery bypass grafting. Four years after the operation, she began to experience hemolysis. Prosthetic valve obstruction was observed but there was no paravalvular leakage or aortic regurgitation through the mechanical valve. We elected to perform apicoaortic bypass in this patient with severe hemolytic anemia secondary to a mechanical valve malfunction.

  3. Transcatheter aortic valve replacement: techniques, complications, and bailout strategies.

    Science.gov (United States)

    Singh, Vikas; Macon, Conrad J; Scot Shaw, Eric; Londoño, Juan C; Martinez, Claudia A

    2013-09-01

    Transcatheter aortic valve replacement has emerged as an alternative option for inoperable or very high-risk patients with severe aortic stenosis-however, there are serious complications associated with the procedure, such as patient mortality, stroke, conduction disturbances, paravalvular regurgitation, and vascular concerns. Our review focuses on the most common complications related to transcatheter aortic valve replacement procedures and potential bailout strategies and techniques.

  4. Transcatheter aortic valve prosthesis surgically replaced 4 months after implantation

    DEFF Research Database (Denmark)

    Thyregod, Hans Gustav; Lund, Jens Teglgaard; Engstrøm, Thomas;

    2010-01-01

    Transcatheter aortic valve implantation is a new and rapidly evolving treatment option for high-risk surgical patients with degenerative aortic valve stenosis. Long-term results with these new valve prostheses are lacking, and potential valve dysfunction and failure would require valve replacement....... We report the first case of surgical valve replacement in a patient with a dysfunctional transcatheter-implanted aortic valve prosthesis 4 months after implantation....

  5. Acute aortic syndromes: Role of multi-detector row CT

    Energy Technology Data Exchange (ETDEWEB)

    Salvolini, Luca; Renda, Pietro [Department of Radiology, University ' Politecnica delle Marche' , Ancona (Italy); Fiore, Davide [Department of Radiology, University of Padova, Padova (Italy); Scaglione, Mariano [Emergency and Trauma CT Section, Department of Radiology, Cardarelli Hospital, Naples (Italy); Piccoli, GianPiero [Cardiosurgery Division, Ospedali Riuniti ' Torrette-Lancisi-Salesi' , Ancona (Italy); Giovagnoni, Andrea [Department of Radiology, University ' Politecnica delle Marche' , Ancona (Italy)], E-mail: a.giovagnoni@univpm.it

    2008-03-15

    Acute thoracic aortic syndromes encompass a spectrum of emergencies including aortic dissection, intramural haematoma, penetrating atherosclerotic ulcer and aneurysm rupture. All these life-threatening conditions require prompt diagnosis and appropriate management. To date multi-detector row Computed Tomography represents a valuable diagnostic tool especially in the emergency setting. This paper focus on the use of multi-detector row Computed Tomography in the evaluation of acute thoracic aortic syndromes and illustrates the key imaging findings related to each disease.

  6. Acute aortic and mitral valve regurgitation following blunt chest trauma.

    Science.gov (United States)

    Bernabeu, Eduardo; Mestres, Carlos A; Loma-Osorio, Pablo; Josa, Miguel

    2004-03-01

    Traumatic rupture of intracardiac structures is an uncommon phenomenon although there are a number of reports with regards to rupture of the tricuspid, mitral and aortic valves. We report the case of a 25-year-old patient who presented with acute aortic and mitral valve regurgitation of traumatic origin. Both lesions were seen separated by 2 weeks. Pathophysiology is reviewed. The combination of both aortic and mitral lesions following blunt chest trauma is almost exceptional.

  7. Technical tips for abdominal aortic endografting.

    Science.gov (United States)

    Murphy, Erin H; Arko, Frank R

    2008-03-01

    Favorable clinical results combined with increased patient demand for minimally invasive surgery has resulted in an increased application of endovascular aortic aneurysm repair (EVAR), and this treatment modality is now being extended to younger, healthier patients. While it seems that EVAR is becoming a desirable option for many patients, it is essential to realize that the feasibility of the procedure may be limited at times by patient anatomy and technical difficulties. Specific anatomical difficulties can be imposed by difficult access, short tortuous and calcified aortic and iliac landing zones, and presence of coincident complex iliac aneurysms. Renal failure has also presented a concern for patients being considered for treatment with EVAR, as the contrast loads required for the procedure, as well as for continued postoperative surveillance, may place the patient at risk. We will discuss technical maneuvers and considerations when encountering difficult anatomy and challenging surgical procedures.

  8. Glucose Suppresses Biological Ferroelectricity in Aortic Elastin

    Science.gov (United States)

    Liu, Yuanming; Wang, Yunjie; Chow, Ming-Jay; Chen, Nataly Q.; Ma, Feiyue; Zhang, Yanhang; Li, Jiangyu

    2013-04-01

    Elastin is an intriguing extracellular matrix protein present in all connective tissues of vertebrates, rendering essential elasticity to connective tissues subjected to repeated physiological stresses. Using piezoresponse force microscopy, we show that the polarity of aortic elastin is switchable by an electrical field, which may be associated with the recently discovered biological ferroelectricity in the aorta. More interestingly, it is discovered that the switching in aortic elastin is largely suppressed by glucose treatment, which appears to freeze the internal asymmetric polar structures of elastin, making it much harder to switch, or suppressing the switching completely. Such loss of ferroelectricity could have important physiological and pathological implications from aging to arteriosclerosis that are closely related to glycation of elastin.

  9. Multislice CT angiography of interrupted aortic arch

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Dong Hyun; Goo, Hyun Woo [Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea); Seo, Dong-Man; Yun, Tae-Jin; Park, Jeong-Jun [Asan Medical Center, University of Ulsan College of Medicine, Department of Paediatric Cardiac Surgery, Seoul (Korea); Park, In-Sook; Ko, Jae Kon; Kim, Young Hwee [Asan Medical Center, University of Ulsan College of Medicine, Department of Paediatric Cardiology, Seoul (Korea)

    2008-01-15

    Interrupted aortic arch (IAA) is defined as complete luminal and anatomic discontinuity between the ascending and descending aorta. Because almost all patients with IAA become critically ill during the neonatal period, they should undergo urgent corrective surgery. This clinical urgency necessitates a fast and accurate noninvasive diagnostic method. Although echocardiography remains the primary imaging tool for this purpose, it is not always sufficient for planning surgical correction of IAA, principally due to a limited acoustic window and the inexperience of imagers. In this context, multislice CT angiography is regarded as an appropriate imaging technique complementary to echocardiography because it is fast, accurate, and objective for the diagnosis of IAA. In this article we describe what cardiac radiologists should know about IAA in their clinical practice, including clinicopathological features, CT features with contemporary surgical methods and postoperative complications, and differentiation from coarctation of the aorta and aortic arch atresia. (orig.)

  10. Glucose Suppresses Biological Ferroelectricity in Aortic Elastin

    Science.gov (United States)

    Liu, Yuanming; Wang, Yunjie; Chow, Ming-Jay; Chen, Nataly Q.; Ma, Feiyue; Zhang, Yanhang; Li, Jiangyu

    2013-01-01

    Elastin is an intriguing extracellular matrix protein present in all connective tissues of vertebrates, rendering essential elasticity to connective tissues subjected to repeated physiological stresses. Using piezoresponse force microscopy, we show that the polarity of aortic elastin is switchable by an electrical field, which may be associated with the recently discovered biological ferroelectricity in the aorta. More interestingly, it is discovered that the switching in aortic elastin is largely suppressed by glucose treatment, which appears to freeze the internal asymmetric polar structures of elastin, making it much harder to switch, or suppressing the switching completely. Such loss of ferroelectricity could have important physiological and pathological implications from aging to arteriosclerosis that are closely related to glycation of elastin. PMID:23679639

  11. 乌司他丁对双瓣置换患者围术期溶酶体膜稳定性及凝血功能的影响%Effects of ulinastatin on the stability of lysosomal membrane and blood coagulation functions in patients undergoing mitral and aortic valves replacement:a double blinded randomized controlled study

    Institute of Scientific and Technical Information of China (English)

    王臻; 程亮; 曹轶; 赵璧君; 张秀静; 金振晓

    2013-01-01

    目的观察体外循环中应用乌司他丁对双瓣置换患者围术期溶酶体膜稳定性及凝血功能的影响。方法在体外循环下行二尖瓣联合主动脉瓣置换患者20例,随机分为乌司他丁组及对照组,乌司他丁组患者按20000 U/kg总量给予乌司他丁,其中半量预充,半量于主动脉开放前加入到体外循环管路中,对照组患者给予等量生理盐水。分别于术前30 min,体外循环60 min、120 min及体外循环结束后30 min采集血样,ELISA方法检测血浆中组织蛋白酶D( CTSD)及N-乙酰-β-D-氨基葡萄糖苷酶( NAG)含量;采用血栓弹力图比较手术前后凝血功能。同时,记录术后ICU滞留时间、引流量、24 h尿量及呋塞米用量,以及术后呼吸机辅助时间、死亡等情况。结果两组患者均顺利出院,无死亡,无严重并发症;术后ICU时间、机械通气时间、术后第1个24小时尿量及呋塞米用量组间无显著差异( P>0.05);与对照组比较,凝血功能各项指标在手术结束后未见明显差异( P>0.05);体外循环过程中各时间点NAG及CTSD含量组间无显著差异( P>0.05)。结论体外循环中应用乌司他丁20000 U/kg对双瓣置换患者围术期溶酶体稳定性及凝血功能的保护作用与对照组没有明显差异。%Objective To investigate the effects of ulinastatin on the stability of lysosomal membrane and blood coagulation functions in patients undergoing mitral and aortic valves replacement .Methods Twenty consecutive patients scheduled for mitral and aortic valve replacement surgery under cardiopulmonary bypass (CPB) were randomized into two groups:ulinastatin group , who received 20 000 U/kg ulinastatin during CPB with half added into the prime solution and half added to the circuit upon aortic clamping removal;control group , who received same volume of saline .Blood sample were collected at 30 min before the operation ,60 min and 120

  12. Apyrexic Brucella melitensis aortic valve endocarditis.

    Science.gov (United States)

    al-Mudallal, D S; Mousa, A R; Marafie, A A

    1989-10-01

    The case of a young shepherd with Brucella melitensis aortic valve endocarditis is presented. His illness ran an afebrile course and was also complicated by disseminated intravascular coagulation (DIC), nephritis, hepatitis and peritonitis, all of which responded well to supportive measures and a combination of tetracycline, trimethoprim-sulphamethoxazole and amikacin sulphate. The fact that even the most severe case of brucellosis can present without fever is stressed.

  13. Evaluation of regional aortic distensibility using color kinesis.

    Science.gov (United States)

    Kato, Yoshimasa; Kotoh, Keiju; Yamashita, Akio; Furuta, Hidetoshi; Shimazu, Chikasi; Misaki, Takurou

    2003-01-01

    Regional aortic stiffness cannot be evaluated by conventional methods. Regional aortic wall velocity during systole in the descending aorta was evaluated by using transesophageal echocardiography with color kinesis. The authors defined regional aortic distensibility (RAD) by considering pulse pressure, with RAD (microm/s/mm Hg) = (regional aortic wall velocity)/(pulse pressure). RAD was evaluated in 38 patients who had coronary artery disease (CAD) and 10 who did not. RAD decreased depending on aging (partial regression coefficient was -5.39 x 10(-1), pkinesis provides information on characteristic difference between calcified and noncalcified plaque.

  14. MicroRNAs, fibrotic remodeling, and aortic aneurysms

    OpenAIRE

    Milewicz, Dianna M.

    2012-01-01

    Aortic aneurysms are a common clinical condition that can cause death due to aortic dissection or rupture. The association between aortic aneurysm pathogenesis and altered TGF-β signaling has been the subject of numerous investigations. Recently, a TGF-β–responsive microRNA (miR), miR-29, has been identified to play a role in cellular phenotypic modulation during aortic development and aging. In this issue of JCI, Maegdefessel and colleagues demonstrate that decreasing the levels of miR-29b i...

  15. FOXE3 mutations predispose to thoracic aortic aneurysms and dissections.

    Science.gov (United States)

    Kuang, Shao-Qing; Medina-Martinez, Olga; Guo, Dong-Chuan; Gong, Limin; Regalado, Ellen S; Reynolds, Corey L; Boileau, Catherine; Jondeau, Guillaume; Prakash, Siddharth K; Kwartler, Callie S; Zhu, Lawrence Yang; Peters, Andrew M; Duan, Xue-Yan; Bamshad, Michael J; Shendure, Jay; Nickerson, Debbie A; Santos-Cortez, Regie L; Dong, Xiurong; Leal, Suzanne M; Majesky, Mark W; Swindell, Eric C; Jamrich, Milan; Milewicz, Dianna M

    2016-03-01

    The ascending thoracic aorta is designed to withstand biomechanical forces from pulsatile blood. Thoracic aortic aneurysms and acute aortic dissections (TAADs) occur as a result of genetically triggered defects in aortic structure and a dysfunctional response to these forces. Here, we describe mutations in the forkhead transcription factor FOXE3 that predispose mutation-bearing individuals to TAAD. We performed exome sequencing of a large family with multiple members with TAADs and identified a rare variant in FOXE3 with an altered amino acid in the DNA-binding domain (p.Asp153His) that segregated with disease in this family. Additional pathogenic FOXE3 variants were identified in unrelated TAAD families. In mice, Foxe3 deficiency reduced smooth muscle cell (SMC) density and impaired SMC differentiation in the ascending aorta. Foxe3 expression was induced in aortic SMCs after transverse aortic constriction, and Foxe3 deficiency increased SMC apoptosis and ascending aortic rupture with increased aortic pressure. These phenotypes were rescued by inhibiting p53 activity, either by administration of a p53 inhibitor (pifithrin-α), or by crossing Foxe3-/- mice with p53-/- mice. Our data demonstrate that FOXE3 mutations lead to a reduced number of aortic SMCs during development and increased SMC apoptosis in the ascending aorta in response to increased biomechanical forces, thus defining an additional molecular pathway that leads to familial thoracic aortic disease.

  16. Transcatheter Aortic Valve Replacement: Comprehensive Review and Present Status

    Science.gov (United States)

    Misenheimer, Jacob A.; Ramaraj, Radhakrishnan

    2017-01-01

    Aortic stenosis is the most common valvular heart disease in the developed world. About 7% of the population over age 65 years suffers from degenerative aortic stenosis. The prognosis of patients with symptomatic severe aortic stenosis is dismal without valve replacement. Even though the American College of Cardiology recommends aortic valve replacement to treat this condition as a class I recommendation, approximately one third of these patients over the age of 75 years are not referred for surgery. Typically, this is from concern about prohibitive surgical risk associated with patient frailty, comorbidities, age, and severe left ventricular dysfunction. The advent in France of transcatheter aortic valve replacement has raised the hope in the United States for an alternative, less invasive treatment for aortic stenosis. Two recent trials—the Placement of AoRTic TraNscathetER Valve Trial Edwards SAPIEN Transcatheter Heart Valve (Partner) and the CoreValve US Pivotal—have established transcatheter aortic valve replacement as the preferred approach in patients who are at high or prohibitive surgical risk. The more recently published Partner 2 trial has shown the feasibility of transcatheter aortic valve replacement in intermediate-surgical-risk patients as well. With a profile that promises easier use and better valve performance and delivery, newer-generation valves have shown their potential for further improvement in safety profile and overall outcomes. We review the history and status of this topic. PMID:28265210

  17. Right aortic arch with coarctation in Chinese children

    Energy Technology Data Exchange (ETDEWEB)

    Ming, Zhu; Aimin, Sun [Shanghai Children' s Medical Center, Department of Radiology, Shanghai (China)

    2008-05-15

    Because of the rarity of right aortic arch coarctation there are few reports of large groups of patients. To characterize the frequency and type of right aortic arch coarctation in a large group of pediatric patients. From June 1997 through May 2007, 11,276 consecutive children with congenital heart disease underwent multidetector CT (MDCT), MRI or angiocardiography examination. All children with a right aortic arch or coarctation were reviewed. Right aortic arch coarctation was found in 11 children representing 0.1% of the total group of 11,276 children, 1.7% of 658 children with native coarctations and 2.3% of 473 children with a right aortic arch. Among the 11 patients, 6 had long-segment narrowing and 7 had an aberrant left subclavian artery. MDCT, MRI and angiocardiography are reliable imaging techniques for the diagnosis of right aortic arch and coarctation. Our findings showed that the pattern of right aortic arch coarctation was different from that of left aortic arch coarctation, suggesting that they are different etiological entities. The pivotal role possibly played by flow dynamics in the development of right aortic arch coarctation is discussed. (orig.)

  18. Asendan Desendan Aortic Bypass: Atan Kalpte Mediyan Sternotomi Yoluyla Onarim

    Directory of Open Access Journals (Sweden)

    Muhammet Akyuz

    2013-10-01

    Full Text Available We report the case of a 9-month-old patient presenting for redo aortic arch surgery because of recoarctation. In present case, ascending-to-descending aortic bypass via median sternotomy was performed without cardiopulmonary bypass with good result. In spite of the fact that the different surgical and intervention treatment options of aortic coarctation are quite satisfactory, a certain group of patients need reoperation because of recoarctation. The recoarctation repair of the aorta with the extra-anatomic aortic bypass is considered a low-risk procedure with high success rate.

  19. Minimally Invasive Transaortic Mitral Decalcification During Aortic Valve Replacement.

    Science.gov (United States)

    Totsugawa, Toshinori; Sakaguchi, Taichi; Hiraoka, Arudo; Matsushita, Hiroshi; Hirai, Yuki; Yoshitaka, Hidenori

    2015-01-01

    Mitral annular calcification accompanied by aortic stenosis is hazardous for both double-valve replacement and transcatheter aortic valve implantation. Less invasive mitral procedure is required in this condition, and minimally invasive approach may further reduce the operative risk in high-risk patients. Here, we report minimally invasive transaortic mitral decalcification during aortic valve replacement through minithoracotomy. We believe that this option is feasible in patients who are at prohibitive risk for double-valve replacement or transcatheter aortic valve implantation because of severe mitral annular calcification.

  20. Aortic aneurysm disease vs. aortic occlusive disease - differences in outcome and intensive care resource utilisation after elective surgery

    DEFF Research Database (Denmark)

    Bisgaard, Jannie; Gilsaa, Torben; Rønholm, Ebbe;

    2013-01-01

    clamping is more pronounced in patients with aortic aneurysm disease, which may affect outcome. OBJECTIVES: The aim of this observational cohort study was to evaluate outcome after open elective abdominal aortic surgery, hypothesising a higher 30-day mortality, a higher incidence of postoperative organ...... dysfunction and a longer length of stay in patients with aortic aneurysm compared with aortic occlusive disease. DESIGN: Cohort observational study based on prospective registrations from national databases. SETTING: Eight Danish hospitals, including four university and four non-university centres, from 1...... or inotropes, ICU stay more than 24 h, hospital length of stay and mortality. RESULTS: Compared with aortic occlusive disease, more patients with aortic aneurysm disease had ICU stays more than 24 h (62 vs. 45%, P ...

  1. Aortic valve replacement with concomitant annular enlargement for small aortic annulus of less than 19 mm.

    Science.gov (United States)

    Takakura, H; Sasaki, T; Hashimoto, K; Hachiya, T; Onoguchi, K; Oshiumi, M; Takeuchi, S

    2000-06-01

    Three female patients with aortic stenosis associated with a severely small annulus underwent aortic valve replacement. In intraoperative measurements, a 19-mm obtulator could not pass through the aortic annulus in each case. We therefore concluded that it would be difficult to implant an appropriate-sized prosthesis in a routine fashion, so we performed an annular enlargement in a modified Nicks procedure. By using a wide teardrop-shaped patch for enlargement and slightly tilting insertion of a prosthesis, a 21 mm bileaflet mechanical prosthesis could be inserted into the enlarged annulus. Despite being a simpler method than other enlarging procedures, a two- or three-sizes larger prosthesis than the native annulus can be inserted with relative ease. Thus, the use of a 19 mm mechanical prosthesis may be avoidable in most adult cases.

  2. Transcatheter Versus Surgical Aortic Valve Replacement in Patients With Severe Aortic Valve Stenosis

    DEFF Research Database (Denmark)

    Thyregod, Hans Gustav; Steinbrüchel, Daniel Andreas; Ihlemann, Nikolaj

    2015-01-01

    outcome was the composite rate of death from any cause, stroke, or myocardial infarction (MI) at 1 year. RESULTS: A total of 280 patients were randomized at 3 Nordic centers. Mean age was 79.1 years, and 81.8% were considered low-risk patients. In the intention-to-treat population, no significant...... difference in the primary endpoint was found (13.1% vs. 16.3%; p = 0.43 for superiority). The result did not change in the as-treated population. No difference in the rate of cardiovascular death or prosthesis reintervention was found. Compared with SAVR-treated patients, TAVR-treated patients had more......BACKGROUND: Transcatheter aortic valve replacement (TAVR) is an option in certain high-risk surgical patients with severe aortic valve stenosis. It is unknown whether TAVR can be safely introduced to lower-risk patients. OBJECTIVES: The NOTION (Nordic Aortic Valve Intervention Trial) randomized...

  3. Recurrent Pneumonia due to Double Aortic Arch

    Directory of Open Access Journals (Sweden)

    I. Sedighi

    2012-04-01

    Full Text Available Introduction: Pneumonia is one of the most common infections during childhood. In children with recurrent bacterial pneumonia complete evaluation for underlying factors is necessary. The most common underlying diseases include: antibody deficiencies , cystic fibrosis , tracheoesophageal fistula and increased pulmonary blood flow. Vascular ring and its pressure effect is a less common cause of stridor and recurrent pneumonia. Congenital abnormalities in aortic arch and main branches which form vascular ring around esophagus and trachea with variable pressure effect cause respiratory symptoms such as stridor , wheezing and recurrent pneumoniaCase Report: A 2 year old boy was admitted in our hospital with respiratory distress and cough . Chest x-Ray demonstrated right lobar pneumonia. He had history of stridor and wheezing from neonatal period and hospitalization due to pneumonia for four times. The patient received appropriate antibiotics. Despite fever and respiratory distress improvement, wheezing continued. Review of his medical documents showed fixed pressure effect on posterior aspect of esophagus in barium swallow. In CT angiography we confirmed double aortic arch.Conclusion: Double aortic arch is one of the causes of persistant respiratory symptom and recurrent pneumonia in children for which fluoroscopic barium swallow is the first non-invasive diagnostic method.(Sci J Hamadan Univ Med Sci 2012;19(1:70-74

  4. Acute aortic dissection: be aware of misdiagnosis

    Directory of Open Access Journals (Sweden)

    Asteri Theodora

    2009-02-01

    Full Text Available Abstract Background Acute aortic dissection (AAD is a life-threatening condition requiring immediate assessment and therapy. A patient suffering from AAD often presents with an insignificant or irrelevant medical history, giving rise to possible misdiagnosis. The aim of this retrospective study is to address the problem of misdiagnosing AD and the different imaging studies used. Methods From January 2000 to December 2004, 49 patients (41 men and 8 women, aged from 18–75 years old presented to the Emergency Department of our hospital for different reasons and finally diagnosed with AAD. Fifteen of those patients suffered from arterial hypertension, one from giant cell arteritis and another patient from Marfan's syndrome. The diagnosis of AAD was made by chest X-ray, contrast enhanced computed tomography (CT, transthoracic echocardiography (TTE and coronary angiography. Results Initial misdiagnosis occurred in fifteen patients (31% later found to be suffering from AAD. The misdiagnosis was myocardial infarction in 12 patients and cerebral infarction in another three patients. Conclusion Aortic dissection may present with a variety of clinical manifestations, like syncope, chest pain, anuria, pulse deficits, abdominal pain, back pain, or acute congestive heart failure. Nearly a third of the patients found to be suffering from AD, were initially otherwise diagnosed. Key in the management of acute aortic dissection is to maintain a high level of suspicion for this diagnosis.

  5. Importance of stent-graft design for aortic arch aneurysm repair

    Directory of Open Access Journals (Sweden)

    C Singh

    2017-02-01

    Full Text Available Aneurysm of the aorta is currently treated by open surgical repair or endovascular repair. However, when the aneurysm occurs in regions between the aortic arch and proximal descending aorta, it can be a complex pathology to treat due to its intricate geometry. When complex aortic aneurysms are treated with the conventional procedures, some of the patients present with significant post-operative complications and high mortality rate. Consequently, a clinically driven hybrid innovation known as the frozen elephant trunk procedure was introduced to treat complex aortic aneurysms. Although this procedure significantly reduces mortality rate and operating time, it is still associated with complications such as endoleaks, spinal cord ischemia, renal failure and stroke. Some of these complications are consequences of a mismatch in the biomechanical behaviour of the stent-graft device and the aorta. Research on complex aneurysm repair tended to focus more on the surgical procedure than the stent-graft design. Current stent-graft devices are suitable for straight vessels. However, when used to treat aortic aneurysm with complex geometry, these devices are ineffective in restoring the normal biological and biomechanical function of the aorta. A stent-graft device with mechanical properties that are comparable with the aorta and aortic arch could possibly lead to fewer post-operative complications, thus, better outcome for patients with complex aneurysm conditions. This review highlights the influence stent-graft design has on the biomechanical properties of the aorta which in turn can contribute to complications of complex aneurysm repair. Design attributes critical for minimising postoperative biomechanical mismatch are also discussed.

  6. HAS-1 genetic polymorphism in sporadic abdominal aortic aneurysm

    Directory of Open Access Journals (Sweden)

    Alberto Balbarini

    2009-04-01

    Full Text Available The hyaluronan synthase 1 (HAS-1 gene encodes a plasma membrane protein that synthesizes hyaluronan (HA, an extracellular matrix molecule. Accumulating evidence emphasizes the relevance of HA metabolism in an increasing number of processes of clinical interest, including abdominal aortic aneurysm (AAA. The existence of aberrant splicing variants of the HAS-1 gene could partly explain the altered extracellular matrix architecture and influence various biological functions, resulting in progressive arterial wall failure in the development of AAA. In the present study, we assessed the hypothesis that HAS-1 genetic 833A/G polymorphism could be associated with the risk of AAA by performing a case-control association study, involving AAA patients and healthy matched donors.

  7. Comparative in Vitro Research of the Human Aortic Bioprosthesis

    Directory of Open Access Journals (Sweden)

    Dawidowska K.

    2014-12-01

    Full Text Available Evaluate of the usefulness and reliability of structures based on the analysis of recorded parameters determining the flow through the Human Aortic Bioprosthesis (HAB have been dealt with. By flow parameters changes determining the performance environment of prosthesis analyzed change of the motion dynamics of the valve leaflets as a function of pressure, thereby determining the degree of alignment of the prosthesis to the performance conditions. Based on the gathered measurement data a comparative analysis of flow rate valve prostheses for different frequency values of the piston pump imitating the heart, different ejection capacity and pressure conditioning work environment prosthesis were studied. Interpretation of the recorded image gave the basis for determining the Effective Orifice Area (EOC.

  8. Hemodynamic predictors of aortic dilatation in bicuspid aortic valve by velocity-encoded cardiovascular magnetic resonance

    Directory of Open Access Journals (Sweden)

    Ramamurthy Senthil

    2010-01-01

    Full Text Available Abstract Background Congenital Bicuspid Aortic Valve (BAV is a significant risk factor for serious complications including valve dysfunction, aortic dilatation, dissection, and sudden death. Clinical tools for identification and monitoring of BAV patients at high risk for development of aortic dilatation, an early complication, are not available. Methods This paper reports an investigation in 18 pediatric BAV patients and 10 normal controls of links between abnormal blood flow patterns in the ascending aorta and aortic dilatation using velocity-encoded cardiovascular magnetic resonance. Blood flow patterns were quantitatively expressed in the angle between systolic left ventricular outflow and the aortic root channel axis, and also correlated with known biochemical markers of vessel wall disease. Results The data confirm larger ascending aortas in BAV patients than in controls, and show more angled LV outflow in BAV (17.54 ± 0.87 degrees than controls (10.01 ± 1.29 (p = 0.01. Significant correlation of systolic LV outflow jet angles with dilatation was found at different levels of the aorta in BAV patients STJ: r = 0.386 (N = 18, p = 0.048, AAO: r = 0.536 (N = 18, p = 0.022, and stronger correlation was found with patients and controls combined into one population: SOV: r = 0.405 (N = 28, p = 0.033, STJ: r = 0.562 (N = 28, p = 0.002, and AAO r = 0.645 (N = 28, p Conclusions The results of this study provide new insights into the pathophysiological processes underlying aortic dilatation in BAV patients. These results show a possible path towards the development of clinical risk stratification protocols in order to reduce morbidity and mortality for this common congenital heart defect.

  9. Role of transesophageal echocardiography in percutaneous aortic valve replacement with the CoreValve Revalving system.

    Science.gov (United States)

    Berry, Colin; Oukerraj, Latifa; Asgar, Anita; Lamarche, Yoan; Marcheix, Bertrand; Denault, André Y; Laborde, Jean-Claude; Cartier, Raymond; Ducharme, Anique; Bonan, Raoul; Basmadjian, Arsène J

    2008-09-01

    Percutaneous aortic valve replacement (PAVR) is an emerging therapy for nonsurgical patients with severe aortic stenosis (AS). We examined the role of transesophageal echocardiography (TEE) in PAVR. TEE was used initially to assess the native valve and aortic root, and served as a guide during PAVR. Following prosthetic valve deployment, TEE was used to assess valve function. Eleven patients aged 82 +/- 10 years with NYHA III-IV underwent PAVR. Periprocedural TEE gave immediate information on prosthetic position and function, LV function, mitral regurgitation, pericardium, and thoracic aorta anatomy. There was excellent visual agreement between fluoroscopic and TEE images of prosthetic positioning and deployment. TEE facilitated the detection and management of procedure-related complications. Compared with pre-PAVR, AV area (0.56 +/- 0.19 cm(2) vs. 1.3 +/- 0.4 cm(2); P < 0.001) and LVEF (49 +/- 17% vs. 56 +/- 11%; P < 0.001) increased. TEE provides key anatomical and functional information, and serves as a diagnostic guide for complications, which may arise during PAVR.

  10. Noninvasively assessed pulsatility of ascending aortic pressure waveform is associated with the presence of coronary artery narrowing.

    Science.gov (United States)

    Wykretowicz, Andrzej; Metzler, Lidia; Milewska, Agata; Balinski, Marek; Rutkowska, Agnieszka; Adamska, Karolina; Krauze, Tomasz; Guzik, Przemysław; Dziarmaga, Mieczysław; Wysocki, Henryk

    2008-01-01

    Several hemodynamic indices, measured invasively in the ascending aorta during routine angiography, are related to the presence and severity of coronary atherosclerosis. Radial artery tonometry, when combined with a validated transfer function, offers the possibility of noninvasive assessment of central arterial pressure. We aim to evaluate the association between noninvasive indices of aortic or radial pressure waveforms and the presence of a significant coronary stenosis. Patients who underwent elective coronary angiography were studied (110 men, 91 women, mean age 53 +/- 0.9 years). Noninvasive measurement of their central hemodynamics was performed by analysis of the aortic pressure waveform derived from the radial artery. An increase in aortic fractional pulse pressure was associated with coronary artery narrowing or previous myocardial infarction. After multivariate adjustment, the odds ratio and confidence intervals (CI) of having a significant coronary aortic stenosis was 1.72 (95% CI, 1.1-2.7) and of previous myocardial infarction 1.6 (95% CI, 1.1-2.2). An increase in noninvasively assessed aortic fractional pulse pressure, but not of the peripheral index is significantly associated with the presence of coronary artery disease.

  11. Non-anatomical implantation of supra-aortic branches for customizing the standard form of Thoraflex™ hybrid prosthesis to a patient's anatomical requirements.

    Science.gov (United States)

    Urbanski, Paul P; Irimie, Vadim; Zembala, Michal

    2016-01-01

    Frozen elephant trunk technique represents a valuable therapeutic option for patients with extensive pathology of thoracic aorta. Thoraflex™ hybrid prosthesis (Vascutek, Terumo, Inchinnan, UK) is one of the commercially available devices in which a stent graft is combined with branched vascular tube mimicking the aortic arch anatomy. Owing to the sewing collar between the stented and unstented portions, this hybrid prosthesis offers a valuable addition to the surgical armamentarium for patients with huge thoracic aorta aneurysms, in whom the aortic diameter exceeds the diameter of available stent grafts. However, the standard factory form of the quadrifurcated arch prosthesis does not always fit to the patient's anatomy and demands a deviation from the anatomical anastomosing of the branches with the respective supra-aortic arteries. A technique of non-anatomical implantation of supra-aortic arteries for customizing the standard form of the Thoraflex prosthesis is described, which facilitates the surgery without limiting the functionality of this hybrid prosthesis.

  12. Minimally invasive aortic valve replacement - pros and cons of keyhole aortic surgery.

    Science.gov (United States)

    Kaczmarczyk, Marcin; Szałański, Przemysław; Zembala, Michał; Filipiak, Krzysztof; Karolak, Wojciech; Wojarski, Jacek; Garbacz, Marcin; Kaczmarczyk, Aleksandra; Kwiecień, Anna; Zembala, Marian

    2015-06-01

    Over the last twenty years, minimally invasive aortic valve replacement (MIAVR) has evolved into a safe, well-tolerated and efficient surgical treatment option for aortic valve disease. It has been shown to reduce postoperative morbidity, providing faster recovery and rehabilitation, shorter hospital stay and better cosmetic results compared with conventional surgery. A variety of minimally invasive accesses have been developed and utilized to date. This concise review demonstrates and discusses surgical techniques used in contemporary approaches to MIAVR and presents the most important results of MIAVR procedures.

  13. Minimally invasive aortic valve replacement – pros and cons of keyhole aortic surgery

    Science.gov (United States)

    Szałański, Przemysław; Zembala, Michał; Filipiak, Krzysztof; Karolak, Wojciech; Wojarski, Jacek; Garbacz, Marcin; Kaczmarczyk, Aleksandra; Kwiecień, Anna; Zembala, Marian

    2015-01-01

    Over the last twenty years, minimally invasive aortic valve replacement (MIAVR) has evolved into a safe, well-tolerated and efficient surgical treatment option for aortic valve disease. It has been shown to reduce postoperative morbidity, providing faster recovery and rehabilitation, shorter hospital stay and better cosmetic results compared with conventional surgery. A variety of minimally invasive accesses have been developed and utilized to date. This concise review demonstrates and discusses surgical techniques used in contemporary approaches to MIAVR and presents the most important results of MIAVR procedures. PMID:26336491

  14. Endovascular Repair of Acute Uncomplicated Aortic Type B Dissection Promotes Aortic Remodelling

    DEFF Research Database (Denmark)

    Brunkwall, J; Kasprzak, P; Verhoeven, E

    2014-01-01

    treatment (BMT) with BMT and Gore TAG stent graft in patients with uncomplicated AD. The primary endpoint was a combination of incomplete/no false lumen thrombosis, aortic dilatation, or aortic rupture at 1 year. METHODS: The AD history had to be less than 14 days, and exclusion criteria were rupture......, impending rupture, malperfusion. Of the 61 patients randomised, 80% were DeBakey type IIIB. RESULTS: Thirty-one patients were randomised to the BMT group and 30 to the BMT+TAG group. Mean age was 63 years for both groups. The left subclavian artery was completely covered in 47% and in part in 17...

  15. Feasibility study of the non-invasive estimation of the {beta}{sup +} arterial input function for human PET imaging; Etude de faisabilite de l'estimation non-invasive de la fonction d'entree arterielle {beta}{sup +} pour l'imagerie TEP chez l'homme

    Energy Technology Data Exchange (ETDEWEB)

    Hubert, X.

    2009-12-15

    This work deals with the estimation of the concentration of molecules in arterial blood which are labelled with positron-emitting radioelements. This concentration is called '{beta}{sup +} arterial input function'. This concentration has to be estimated for a large number of pharmacokinetic analyses. Nowadays it is measured through series of arterial sampling, which is an accurate method but requiring a stringent protocol. Complications might occur during arterial blood sampling because this method is invasive (hematomas, nosocomial infections). The objective of this work is to overcome this risk through a non-invasive estimation of {beta}{sup +} input function with an external detector and a collimator. This allows the reconstruction of blood vessels and thus the discrimination of arterial signal from signals in other tissues. Collimators in medical imaging are not adapted to estimate {beta}{sup +} input function because their sensitivity is very low. During this work, they are replaced by coded-aperture collimators, originally developed for astronomy. New methods where coded apertures are used with statistical reconstruction algorithms are presented. Techniques for analytical ray-tracing and for the acceleration of reconstructions are proposed. A new method which decomposes reconstructions on temporal sets and on spatial sets is also developed to efficiently estimate arterial input function from series of temporal acquisitions. This work demonstrates that the trade-off between sensitivity and spatial resolution in PET can be improved thanks to coded aperture collimators and statistical reconstruction algorithm; it also provides new tools to implement such improvements. (author)

  16. Unreliability of aortic size index to predict risk of aortic dissection in a patient with Turner syndrome

    Science.gov (United States)

    Nijs, Jan; Gelsomino, Sandro; Lucà, Fabiana; Parise, Orlando; Maessen, Jos G; Meir, Mark La

    2014-01-01

    Aortic size index (ASI) has been proposed as a reliable criterion to predict risk for aortic dissection in Turner syndrome with significant thresholds of 20-25 mm/m2. We report a case of aortic arch dissection in a patient with Turner syndrome who, from the ASI thresholds proposed, was deemed to be at low risk of aortic dissection or rupture and was not eligible for prophylactic surgery. This case report strongly supports careful monitoring and surgical evaluation even when the ASI is < 20 mm/m2 if other significant risk factors are present. PMID:24944765

  17. Transcatheter aortic valve repair for management of aortic insufficiency in patients supported with left ventricular assist devices.

    Science.gov (United States)

    Pal, Jay D; McCabe, James M; Dardas, Todd; Aldea, Gabriel S; Mokadam, Nahush A

    2016-10-01

    The development of new aortic insufficiency after a period of support with a left ventricular assist device can result in progressive heart failure symptoms. Transcatheter aortic valve repair can be an effective treatment in selected patients, but the lack of aortic valve calcification can result in unstable prostheses or paravalvular leak. We describe a technique of deploying a self-expanding CoreValve (Medtronic, Minneapolis, MN, USA) into the aortic annulus, followed by a balloon-expandable SAPIEN-3 (Edwards, Irvine, CA, USA).

  18. Abdominal aortic aneurysm is associated with a variant in low-density lipoprotein receptor-related protein 1

    DEFF Research Database (Denmark)

    Bown, Matthew J; Jones, Gregory T; Harrison, Seamus C

    2011-01-01

    Abdominal aortic aneurysm (AAA) is a common cause of morbidity and mortality and has a significant heritability. We carried out a genome-wide association discovery study of 1866 patients with AAA and 5435 controls and replication of promising signals (lead SNP with a p value ... demonstrated a trend toward increased LRP1 expression for the rs1466535 CC genotype in arterial tissues; there was a significant (p = 0.029) 1.19-fold (1.04-1.36) increase in LRP1 expression in CC homozygotes compared to TT homozygotes in aortic adventitia. Functional studies demonstrated that rs1466535 might...

  19. Neonate Aortic Stenosis: Importance of Myocardial Perfusion in Prognosis

    Directory of Open Access Journals (Sweden)

    Marco Aurélio Santos

    2002-09-01

    Full Text Available OBJECTIVE: To analyze our experience with percutaneous aortic balloon valvuloplasty in newborn infants with aortic stenosis, emphasizing the extraordinary importance of myocardial perfusion.METHODS: Over a 10-year-period, 21 neonates underwent percutaneous aortic balloon valvuloplasty. Age ranged from 2 to 27 days, weight ranged from 2.2 to 4.1 kg and 19 were males. All patients presented with congestive heart failure that could not be treated clinically. The onset of symptoms in the first week of life occurred in 9 patients considered as having critical aortic stenosis. Severe aortic stenosis occurred in 12 patients with the onset of symptoms in the second week of life.RESULTS: Mortality reached 100% in the patients with critical aortic stenosis. The procedure was considered effective in the 12 patients with severe aortic stenosis. Vascular complications included the loss of pulse in 12 patients and rupture of the femoral artery in 2 patients. Cardiac complications included acute aortic regurgitation in 2 patients and myocardial perforation in one. In an 8.2±1.3-year follow-up, 5 of the 12 patients died (2 patients due to septicemia and 3 patients due to congestive heart failure. Five of the other 7 patients underwent a new procedure and 2 required surgery.CONCLUSION: Percutaneous aortic valvuloplasty in neonates is not an effective procedure in the 1st week of life, because at this age the common presentation is cardiogenic shock. It is possible that, in those patients with critical aortic stenosis, dilation of the aortic valve during fetal life may change the prognosis of its clinical outcome.

  20. Extended Durability of a Cloth-Covered Star-Edwards Caged Ball Prosthesis in Aortic Position

    Directory of Open Access Journals (Sweden)

    Yusuf Ata

    2009-01-01

    Full Text Available The Starr-Edwards caged ball valve is one of the oldest cardiac valve prosthesis and was widely used all around the world in the past decades. Despite the long-term results that have been reported there are only a few cases reported that exceed 30 years of durability. Here in, we report a 53-year-old patient with a well-functioning 35-year-old aortic Starr-Edwards caged ball prosthesis.