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Wainwright John M - - 2012
Surgical reconstruction of congenital heart defects is often limited by the nonresorbable material used to approximate normal anatomy. In contrast, biologic scaffold materials composed of resorbable non-cross-linked extracellular matrix (ECM) have been used for tissue reconstruction of multiple organs and are replaced by host tissue. Preparation of whole organ ECM ...
Lee W-N - - 2011
The assessment of disrupted myocardial fiber arrangement may help to understand and diagnose hypertrophic or ischemic cardiomyopathy. We hereby proposed and developed Shear Wave Imaging (SWI), which is an echocardiographybased, noninvasive, real-time, and easy-to-use technique, to map myofiber orientation. Five in vitro porcine and three in vivo openchest ovine hearts ...
Gaasch William H - - 2011
The changes in left ventricular (LV) structure and geometry that evolve after myocardial injury or overload usually involve chamber dilation and/or hypertrophy. Such architectural remodeling can be classified as eccentric or concentric. Consideration of LV volume, mass, and relative wall thickness (or mass/volume) allows classification of LV remodeling that includes ...
Savinova Olga V - - 2012
Structural remodeling is a major feature of heart failure and typically precedes the development of symptomatic disease. Structural remodeling of the heart reflects changes in myocyte morphology. Disproportional myocyte growth is observed in pathologic concentric hypertrophy (myocyte thickening) and in eccentric dilated hypertrophy (myocyte lengthening). Alterations in myocyte shape lead ...
Salgo Ivan S - - 2011
BACKGROUND: Left ventricular (LV) volumes and ejection fraction derived from two-dimensional echocardiography are two measures of adverse LV remodeling, which predict survival in patients with systolic heart failure. However, the geometric assumptions and image foreshortening that can occur with two-dimensional echocardiography reduces measurement accuracy and thus predictive value. By its ...
Collier P - - 2011
The objective of this study was to investigate the nature and biomechanical properties of collagen fibers within the human myocardium. Targeting cardiac interstitial abnormalities will likely become a major focus of future preventative strategies with regard to the management of cardiac dysfunction. Current knowledge regarding the component structures of myocardial ...
FidziaƄska Anna - - 2011
Ultrastructural analysis was performed in cardiac ceroidlipofuscinosis to confirm the presence and the nature of storage material. Granular osmophilic deposits characteristic of GROD structures coincidented with particularly aberrant mitochondria. Remodeling of mitochondrial interior with the appearance of several form of abnormal inclusions was never observed in cardiac ceroidlipofuscinosis. The presence ...
Argulian Edgar - - 2012
Recent studies have provided new insights into the pathophysiology of congestive heart failure. Organ-specific responses to circulatory disturbances may differ via a hypoperfusion state and a venous congestion state. The liver and the kidneys serve as a good example of a differential injury pattern based on the predominant circulatory insult. ...
Patra Chinmoy - - 2011
The extracellular matrix is crucial for organogenesis. It is a complex and dynamic component that regulates cell behavior by modulating the activity, bioavailability and presentation of growth factors to cell surface receptors. Here, we determined the role of the extracellular matrix protein Nephronectin (Npnt) in heart development using the zebrafish ...
Sachdeva Rajesh - - 2011
Evaluation of ischemia and the extent of viable myocardium is required prior to consideration of revascularizing a lesion after a myocardial infarction in which there is hypo- or akinesis. We present a case in which we utilized FFR of a lesion in a patient whose nuclear study 7 days after ...
Di Martino Elena S - - 2011
Most computational models of the heart have so far concentrated on the study of the left ventricle, mainly using simplified geometries. The same approach cannot be adopted to model the left atrium, whose irregular shape does not allow morphological simplifications. In addition, the deformation of the left atrium during the ...
Constantinides C - - 2011
Catheter-based measurements are extensively used nowadays in animal models to quantify global left ventricular (LV) cardiac function and hemodynamics. Conductance catheter measurements yield estimates of left ventricular volumes. Such estimates, however, are confounded by the catheters non-homogeneous emission field and the contribution to the total conductance of surrounding tissue or ...
Manole C G - - 2011
We used rat experimental myocardial infarction to study the ultrastructural recovery, especially neo-angiogenesis in the infarction border zone. We were interested in the possible role(s) of telocytes (TCs), a novel type of interstitial cell very recently discovered in myocardim (see www.telocytes.com). Indeed, electron microscopy, immunocytochemistry, and analyses of several proangiogenic ...
Przyklenk Karin - - 2011
Remote ischemic preconditioning (RIPC) is the phenomenon whereby brief episodes of ischemia-reperfusion applied in distant tissues or organs render the myocardium resistant to a subsequent sustained episode of ischemia. Reduction of infarct size with RIPC has been documented in response to (i) brief antecedent ischemia in a remote coronary vascular ...
Grapsa Julia - - 2011
Right ventricular function plays an important role in determining cardiac symptoms and exercise capacity in chronic heart failure. It is known that right ventricle has complex anatomy and physiology. The purpose of this review paper is to demonstrate the best assessment of the right ventricle with current echocardiography. Echocardiography can ...
Kai Dan - - 2011
Cardiac tissue engineering (TE) is one of the most promising strategies to reconstruct infarct myocardium and the major challenge is to generate a bioactive substrate with suitable chemical, biological, and conductive properties, thus mimicking the extracellular matrix (ECM) both structurally and functionally. In this study, polypyrrole/poly(ε-caprolactone)/gelatin nanofibrous scaffolds were electrospun ...
Govindan Malini - - 2011
BACKGROUND: The clinical assessment of left atrial function during atrial fibrillation is challenging and often inaccurate because of the beat-to-beat variability in the cycle length. The aim of this study was to validate the use of an index beat, the beat following two preceding cardiac cycles of equal duration, for ...
Kühl J Tobias - - 2011
Measurement of left atrial (LA) maximal volume (LA(max)) using two-dimensional transthoracic echocardiography (TTE) provides prognostic information in several cardiac diseases. However, the relationship between LA(max) and LA function is poorly understood and TTE is less well suited for measuring dynamic LA volume changes. Conversely, cardiac magnetic resonance imaging (CMR) and ...
Palatinus Joseph A JA Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, - - 2012
The precise spatial order of gap junctions at intercalated disks in adult ventricular myocardium is thought vital for maintaining cardiac synchrony. Breakdown or remodeling of this order is a hallmark of arrhythmic disease of the heart. The principal component of gap junction channels between ventricular cardiomyocytes is connexin43 (Cx43). Protein-protein ...
P Prabhakaran Molamma - - 2011
A bioengineered construct that matches the chemical, mechanical, biological properties and extracellular matrix morphology of native tissue could be suitable as a cardiac patch for supporting the heart after myocardial infarction. The potential of utilizing a composite nanofibrous scaffold of poly(dl-lactide-co-glycolide)/gelatin (PLGA/Gel) as a biomimetic cardiac patch is studied by ...
Fontes Magda S C - - 2011
The major gap junction protein expressed in the heart, connexin43 (Cx43), is highly remodeled in the diseased heart. Usually, Cx43 is down-regulated and heterogeneously redistributed to the lateral sides of cardiomyocytes. Reverse remodeling of the impaired Cx43 expression could restore normal cardiac function and normalize electrical stability. In this review, ...
Andersen Garrett Newton GN Levanger Hospital, Nord-Trøndelag Health Trust, Levanger, Norway. - - 2011
To study the reliability and feasibility of point-of-care pocket-sized echocardiography (POCKET) at the bedside in patients admitted to a medical department at a non-university hospital. One hundred and eight patients were randomized to bedside POCKET examination shortly after admission and later high-end echocardiography (HIGH) in the echo-lab. The POCKET examinations ...
Gouveia Veronica - - 2011
The goal of hemodynamic monitoring and management during major surgery is to guarantee adequate organ perfusion, a major prerequisite for adequate tissue oxygenation and thus, end-organ function. Further, hemodynamic monitoring should serve to prevent, detect, and to effectively guide treatment of potentially life-threatening hemodynamic events, such as severe hypovolemia due ...
Buckberg Gerald - - 2011
Ventricular torsion and untwisting are essential for normal ventricular function and their mechanisms are related to the temporal responses of the helical and circular muscle fibers that comprise cardiac architecture. Explanation of the presystolic isovolumic contraction (IVC) period is essential for analysis of these interactions. Structural and imaging studies by ...
Papageorgiou Anna-Pia - - 2011
Viral myocarditis is a life-threatening disease characterized by severe cardiac inflammation that can result in heart failure or sudden cardiac death in previously healthy adults. In a subset of patients, it may result in the development of dilated cardiomyopathy due to the chronic inflammatory process. Despite its clinical need, specific ...
Inaba Shinji - - 2011
'Coronary steal' is frequently observed in the recipient artery supplied from collaterals. Coronary steal during stress may have an adverse effect on myocardial function even in a 'well-collateralized' territory. We experienced one case with functional occlusion in which the coronary steal phenomenon was demonstrated non-invasively using transthoracic Doppler echocardiography. The ...
Güler Ahmet - - 2011
In a dilated heart with impaired systolic functions, functional mitral regurgitation could be seen even in the presence of structurally normal mitral apparatus. A number of mechanisms play role in the development of functional mitral regurgitation. These are increased mitral tethering forces, reduction in closing forces and mechanical and electrical ...
Lampropoulos K K Department of Cardiology, University Hospitals Leuven, Leuven, - - 2011
Myxoma is the most common benign cardiac neoplasm. A 66-year-old woman presented with a large left atrial myxoma, which was detected by a real-time three-dimensional echocardiography (RT3DE) and a real-time three-dimensional transoesophageal echocardiography (RT3D-TEE) approach. RT3DE and RT3D-TEE proved to be techniques that can provide additional contributions to the diagnostic ...
Atkinson Andrew - - 2011
Functioning of the cardiac conduction system depends critically on its structure and its complement of ion channels. Therefore, the aim of this study was to document both the structure and ion channel expression of the left and right ventricular His-Purkinje networks, as we have previously done for the sinoatrial and ...
Seif-Naraghi Sonya B SB University of California, San Diego, La Jolla, CA, - - 2011
The pursuit of alternate therapies for end-stage heart failure post-myocardial infarction has led to the development of a variety of in situ gelling materials to be used as cellular or acellular scaffolds for cardiac repair. Previously, a protocol was established to decellularize human and porcine pericardia and process the extracellular ...
Kai Dan - - 2011
Cardiac tissue engineering (TE) is one of the most promising strategies to reconstruct the infarct myocardium and the major challenge involves producing a bioactive scaffold with anisotropic properties that assist in cell guidance to mimic the heart tissue. In this study, random and aligned poly(ε-caprolactone)/gelatin (PG) composite nanofibrous scaffolds were ...
Li Yinbo Y Department of Biomedical Engineering, University of Virginia, Charlottesville, VA, - - 2011
This study noninvasively evaluated the development of left ventricular (LV) dyssynchrony following reperfused myocardial infarction (MI) in mice using an ultrasonic speckle-tracking method. Eight C57BL/6J mice were assessed by high-resolution echocardiography at baseline and at eight time-points following MI. Images were acquired at 1mm elevational intervals encompassing the entire LV ...
Todiere Giancarlo - - 2011
Consistent evidence shows an impact of systemic haemodynamic overload on the right ventricle, but its functional and structural consequences have received scarce attention for several reasons including the difficult application of conventional imaging techniques due to the complex shape and orientation of that cardiac chamber. To evaluate whether mild to ...
Mukherjee Shayanti - - 2011
In myocardial tissue engineering the use of synthetically bioengineered flexible patches implanted in the infarcted area is considered one of the promising strategy for cardiac repair. In this work the potentialities of a biomimetic electrospun scaffold made of a commercial copolymer of (L: )-lactic acid with trimethylene carbonate (P(L: )LA-co-TMC) ...
Wu Yin - - 2011
PURPOSE: To investigate the transmural heterogeneity of left ventricular myocardium structural remodeling. MATERIALS AND METHODS: Ex vivo diffusion tensor imaging (DTI) was performed in six adult porcine heart samples with apical septum infarction collected 13 weeks after permanent left anterior descending coronary artery ligation and six age-matched intact controls. Alterations ...
Atchley Allen E - - 2011
We hypothesized that the severity of resting perfusion abnormalities assessed by the summed rest score (SRS) would be associated with a higher rate of adverse outcomes in patients with heart failure (HF) and reduced left ventricular (LV) ejection fraction (EF). A subset of 240 subjects from HF-ACTION underwent resting technetium-99m ...
Arias-Godínez José Antonio - - 2011
One of the most common indications in echocardiography is the evaluation of left ventricular function. The traditional measurement of ejection fraction is based upon tracing the left ventricular borders and calculating left ventricular volumes using geometric assumptions. Now, with the introduction of three-dimensional echocardiography, the evaluation of left ventricular function ...
Pandey Anil Kumar - - 2011
Prevalence, determinants, and prognostic value of left ventricular function in subjects with asymptomatic essential hypertension are still incompletely known. The goal of this study was to investigate the effects of asymptomatic untreated essential hypertension on left ventricular structure and function. The left ventricular functions were assessed among 127 hypertensive and ...
Salama Guy - - 2011
Pathophysiological remodeling of cardiac function occurs at multiple levels, spanning the spectrum from molecular and sub-cellular changes to those occurring at the organ-system levels. Of key importance to arrhythmias are changes in electrophysiological and calcium handling properties at the tissue level. In this review, we discuss how high-resolution optical action ...
Dobrilovic Nikola - - 2011
Abstract  Nonmyxomatous tumors of the heart are exceedingly rare in adults. We report a case of symptomatic, massive, right ventricular cardiac fibroma found in an adult. Despite multiple (preoperative) biopsies, diagnosis was made only after surgical excision. (J Card Surg 2011;**:***-***).
Jesty Sophy A - - 2011
Accessory bypass tracts are rarely documented in horses. Here, we present a case of an accessory bypass tract which was initially masked by the presence of atrial fibrillation. Evidence of ventricular pre-excitation was recognized after cardioversion to normal sinus rhythm and the horse was diagnosed with Wolff-Parkinson-White Syndrome. In people, ...
Liu Jiankang - - 2011
Pericardial adipose tissue (PAT), a regional fat depot adjacent to the myocardium, may mediate the complex relation between obesity and cardiac left ventricular (LV) abnormalities. We sought to evaluate the association of PAT with echocardiographic measures of LV abnormalities in the Jackson Heart Study (JHS). A total of 1,414 African ...
Ronchetti A - - 2011
Horses that had been trimmed and shod by apprentice farriers were sourced from the Royal School of Military Engineering, Melton Mowbray (37 horses) and from the Household Cavalry, Knightsbridge (54 horses). The lateral and medial hoof wall angles of both forelimbs were measured using a Ruidoso hoof gauge by the ...
Jiang Lei L Department of Emergency Medicine, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, - - 2011
Although modern cardiopulmonary resuscitation (CPR) substantially decreases the mortality induced by cardiac arrest, cardiac arrest still accounts for over 50% of deaths caused by cardiovascular diseases. In this article, we address the current use of mechanical devices during CPR, and also compare the CPR quality between manual and mechanical chest ...
Vadakkumpadan Fijoy F Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA. - - 2011
Patient-specific simulation of heart (dys)function aimed at personalizing cardiac therapy are hampered by the absence of in vivo imaging technology for clinically acquiring myocardial fiber orientations. In this research, we develop a methodology to predict ventricular fiber orientations of a patient heart, given the geometry of the heart and an ...
Aguilar Gerardo - - 2011
Evaluating the systolic function of the left ventricle (LV) is important in the hemodynamic management of the critically ill patients with circulatory failure. Echocardiography is considered the standard monitor for estimating the LV function at the bedside in the intensive care unit. However, it requires a trained operator and is ...
Alcaraz Raúl R Innovation in Bioengeeniering Research Group, University of Castilla-La Mancha, Campus Universitario, 16071 Cuenca, Spain. - - 2011
Atrial fibrillation (AF) is the most common cardiac arrhythmia in clinical practice. Although its mechanisms are incompletely understood, electrophysiological and structural remodeling of the atria seem to play an important role in the arrhythmia transition from paroxysmal to persistent. However, the time course of the atrial remodeling along onward episodes ...
Castrejón-Castrejón Sergio - - 2011
The efficacy of catheter-based ablation techniques to treat atrial fibrillation is limited not only by recurrences of this arrhythmia but also, and not less importantly, by new-onset organized atrial tachycardias. The incidence of such tachycardias depends on the type and duration of the baseline atrial fibrillation and specially on the ...
Healy Lindsey J - - 2011
Accurate interpretations of cardiac functions require precise structural models of the myocardium, but the latter is not available always and for all species. Although scaling or substitution of myocardial fiber information from alternate species has been used in cardiac functional modeling, the validity of such practice has not been tested. ...
Beltrán-Molina F F Department of Signal Theory and Communications, Universidad Rey Juan Carlos, 28943 Fuenlabrada, Madrid, Spain. - - 2011
Spectral analysis is widely applied to bioelectric cardiac signals for quantifying the spatiotemporal organization of cardiac tissue. Nevertheless, to date it is not well understood how lead characteristics affect the spectrum of recorded cardiac signals and, as a consequence, the interpretation of cardiac spectrum is still controversial. In this paper ...
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