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Hofmann Florian - - 2012
AIMS: Cardiac hypertrophy is accompanied by reprogramming of gene expression, where the altered expression of ion channels decreases electrical stability and increases the risk of life-threatening arrhythmias. However, the underlying mechanisms are not fully understood. Here, we analyze the role of the depolarizing current I(f) which has been hypothesized to ...
Giacopelli Daniele - - 2012
Background: Measuring body surface potentials in the assessment of the electrical activity of the heart is the most commonly used noninvasive method for diagnosing cardiac arrhythmias. Paroxysmal atrial fibrillation (PAF) patients have disturbed cardiac electrophysiology but the detailed characteristics of atrial activation on the body surface are unknown. Methods: P ...
Bhushan Shashi - - 2012
β(2)-adrenoreceptor activation has been shown to protect cardiac myocytes from cell death. We hypothesized that acute β(2)-adrenoreceptor stimulation, using arformoterol (ARF), would attenuate myocardial ischemia/reperfusion (R) injury via NO synthase activation and cause a subsequent increase in NO bioavailability. Male C57BL/6J and endothelial NO synthase (eNOS) knockout mice were subjected ...
Li Jingyuan J Department of Anesthesiology, Division of Molecular Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095-7115, - - 2012
Although the murine late pregnant (LP) heart is speculated to be a better functioning heart during physiological conditions, the susceptibility of LP hearts to I/R injury is still unknown. The aims of this study were to investigate the cardiac vulnerability of LP rodents to ischemia/reperfusion (I/R) injury and to explore ...
Welsh Robert C - - 2012
BACKGROUND: We evaluated the safety, efficacy, and tolerability of elinogrel, a competitive, reversible intravenous and oral P2Y(12) inhibitor that does not require metabolic activation, in patients undergoing nonurgent percutaneous coronary intervention. METHODS AND RESULTS: In a randomized, double-blind, dose-ranging phase 2b trial, 652 patients received either 300 or 600 mg ...
He Weihong - - 2012
Myocardial ischemia is a primary cause for the loss of vital components such as cardiomyocytes in the heart, leading to myocardial infarction and eventual cardiac dysfunction or heart failure. Suppressed angiogenesis plays a determinant role in the pathogenesis of myocardial infarction. In response to myocardial ischemia, hypoxia-inducible factor-1α and 2α ...
Hwan Bae Myung - - 2012
BACKGROUND: The aim of this study was to determine the frequency and nature of errors made by computer electrocardiogram (ECG) analysis of atrial fibrillation (AF), and the clinical consequences. HYPOTHESIS: Computer software for interpreting ECGs has advanced. METHODS: A total of 10279 ECGs were collected, automatically interpreted by the built-in ...
Kukreja Rakesh C RC Pauley Heart Center, Division of Cardiology, Department of Internal Medicine, Virginia Commonwealth University, Richmond, Virginia 23298, USA. - - 2012
Cyclic guanosine monophosphate (cGMP) is an important intracellular second messenger that mediates multiple tissue and cellular responses. The cGMP pathway is a key element in the pathophysiology of the heart and its modulation by drugs such as phosphodiesterase (PDE)-5 inhibitors and guanylate cyclase activators may represent a promising therapeutic approach ...
Batchu Sri N - - 2012
Epoxyeicosatrienoic acids (EETs) are active metabolites of arachidonic acid that are inactivated by soluble epoxide hydrolase enzyme (sEH) to dihydroxyeicosatrienoic acid. EETs are known to render cardioprotection against ischemia reperfusion (IR) injury by maintaining mitochondrial function. We investigated the effect of a novel sEH inhibitor (sEHi) in limiting IR injury. ...
Gheorghiade Mihai - - 2012
The number of annual hospitalizations for heart failure (HF) and the mortality rates among patients hospitalized for HF remains unacceptably high. The search continues for safe and effective agents that improve outcomes when added to standard therapy. The nitric oxide (NO)-soluble guanylate cyclase (sGC)-cyclic guanosine monophosphate (cGMP) pathway serves an ...
Kondoh Haruhiko - - 2012
Abstract  We report a rare case of late left ventricular perforation caused by a migrated pacemaker lead, which had been implanted in the right ventricular septum three months prior. Preoperative computed tomography findings revealed that the tip of the migrated pacemaker lead had perforated the ventricular wall near the intraventricular ...
Ueland Thor - - 2012
BACKGROUND/OBJECTIVES: Heart failure is characterized by disturbed energy metabolism and impaired mitochondrial function. L-carnitine plays a critical role in fatty acid transport into the mitochondria and may thus influence inflammation and myocardial function. The aim of this study was to investigate carnitine metabolism in relation to progression of heart failure ...
Wen Zhuzhi - - 2012
The prognosis of patients with myocardial infarction (MI) and resultant chronic heart failure remains extremely poor despite continuous advancements in optimal medical therapy and interventional procedures. Animal experiments and clinical trials using adult stem cell therapy following MI have shown a global improvement of myocardial function. The emergence of stem ...
Baicu Catalin F - - 2012
Cardiac interstitial fibrillar collagen accumulation, such as that associated with chronic pressure overload (PO), has been shown to impair left ventricular diastolic function. Therefore, insight into cellular mechanisms that mediate excessive collagen deposition in the myocardium is pivotal to this important area of research. Collagen is secreted as a soluble ...
Madonna Rosalinda - - 2012
Several growth factors have been shown to protect the cardiomyocyte from the detrimental effects of acute ischemia-reperfusion injury, through the activation of a variety of cell-surface receptors and the subsequent recruitment of a number of intracellular signal transduction pathways. Among these growth factors, hepatocyte growth factor (HGF), also named as ...
Gao Shan - - 2012
Urotensin II (UII) is a vasoactive peptide which is bound to a G protein-coupled receptor. UII and its receptor are upregulated in ischemic and chronic hypoxic myocardium, but the effect of UII on ischemic reperfusion (I/R) injury is still controversial. The aim of the present study was to investigate whether ...
Yang Hyan Suk - - 2012
OBJECTIVE: The aim of this study is to evaluate the relationship between polarity of left ventricular (LV) pacing and the resultant regional, global, and transmural mechanical sequence of contraction. BACKGROUND: Cardiac resynchronization therapy (CRT) is widely utilized in patients with drug refractory congestive heart failure with systolic dysfunction (EF <35 %) ...
Vo Thang Thanh-Thuy - - 2012
BACKGROUND: Cardiac resynchronization therapy may improve survival and quality of life in patients suffering from heart failure with left ventricular (LV) contraction dyssynchrony. While several studies have investigated electrical or mechanical determinants of synchronous contraction, few have focused on activation contraction coupling at a macroscopic level. OBJECTIVE: The objective of ...
Dworak Melissa - - 2012
Microglia are the immune cells in the central nervous system and can produce cytokines when they are activated by an insult or injury. In the present study, we investigated in detail the time frame of the activation of microglia in the hypothalamic paraventricular nucleus (PVN) following myocardial infarction in rats. ...
Rame J Eduardo - - 2012
Heart Failure is a progressive clinical syndrome marked by venous congestion and maladaptive neurohormonal activation in the setting of left ventricular dysfunction. More recently, another face of this syndrome is beginning to emerge involving metabolic derangements implicating other organs - adipose tissue, skeletal muscle - and the endocrine systems (leptin, ...
Chokshi Aalap - - 2012
Heart failure is associated with impaired myocardial metabolism with a shift from fatty acids to glucose use for ATP generation. We hypothesized that cardiac accumulation of toxic lipid intermediates inhibits insulin signaling in advanced heart failure and that mechanical unloading of the failing myocardium corrects impaired cardiac metabolism. We analyzed ...
Rantner Lukas J LJ Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21218, - - 2012
Defibrillation efficacy is decreased in infarcted hearts, but the mechanisms by which infarcted hearts are more vulnerable to electric shocks than healthy hearts remain poorly understood. The goal of this study was to provide insight into the 3D mechanisms for the increased vulnerability to electric shocks in infarcted hearts. We ...
Song Kunhua - - 2012
The adult mammalian heart possesses little regenerative potential following injury. Fibrosis due to activation of cardiac fibroblasts impedes cardiac regeneration and contributes to loss of contractile function, pathological remodelling and susceptibility to arrhythmias. Cardiac fibroblasts account for a majority of cells in the heart and represent a potential cellular source ...
Huo Y - - 2012
BACKGROUND: Radiofrequency ablation of focal atrial tachycardias (AT) is a validated technique with high success rates. However, electrophysiological (EP) characteristics and ablation strategy of localized reentrant AT originating from the coronary sinus ostium (CSo) have not been reported in detail so far. METHODS: From January 2009 to July 2010, 1,453 ...
Darragh Km - - 2012
AIMS: Most commercially available defibrillators utilise a high tilt waveform. Work in atrial fibrillation has shown improved defibrillation success using low tilt waveforms. We hypothesise that a novel low tilt biphasic waveform will be non-inferior to a standard tilt waveform whilst delivering lower energy for the defibrillation of ventricular arrhythmias ...
McCabe James M - - 2012
BACKGROUND: Rapid activation of the cardiac catheterization laboratory for primary percutaneous coronary intervention (PCI) improves outcomes for ST-segment elevation myocardial infarction (STEMI), but selected emphasis on minimizing time to reperfusion may lead to a greater frequency of false-positive activations. METHODS: We analyzed consecutive patients referred for primary PCI for a ...
Wick Carson A - - 2012
Seismocardiography (SCG), a representation of mechanical heart motion, may more accurately determine periods of cardiac quiescence within a cardiac cycle than the electrically derived electrocardiogram (EKG) and, thus, may have implications for gating in cardiac computed tomography. We designed and implemented a system to synchronously acquire echocardiography, EKG, and SCG ...
Arreguín Francisco - - 2012
Oxidant stress among other effectors, are implicated in the sequel of myocardial reperfusion injury; thereby it is accepted that maintaining the balance between oxidant/antioxidant signaling within the cell will provide protection against reperfusion damage. The cardioprotective strategy of post-conditioning (PC) reduces reperfusion injury through complex mechanisms; however the contribution of ...
Wang Zhi-Hua - - 2012
Intermittent hypobaric hypoxia (IHH) is an effective protective strategy against myocardial ischemia/reperfusion (I/R) injury, but the precise mechanisms are far from clear. To understand the overall effects of IHH on the myocardial proteins during I/R, we analyzed functional performance and protein expression profile in isolated hearts from normoxic and IHH ...
Elliott E B - - 2012
RationaleThe extent to which sarcoplasmic reticulum Ca(2+)ATPase (SERCA) activity alone determines left ventricular (LV) pump function is unknown.ObjectiveTo correlate SERCA activity with hemodynamic function of rabbit LV during thapsigargin perfusion.Methods and ResultsIsolated rabbit hearts were perfused in working heart configuration, and LV pump function was assessed using a pressure-volume catheter. ...
Jousset Florian F Applied Signal Processing Group, Swiss Federal Institute of Technology, Lausanne, - - 2012
Kinetics of Atrial Repolarization Alternans. Repolarization alternans (Re-ALT), a beat-to-beat alternation in action potential repolarization, promotes dispersion of repolarization, wavebreaks, and reentry. Recently, Re-ALT has been shown to play an important role in the transition from rapid pacing to atrial fibrillation (AF) in humans. The detailed kinetics of atrial Re-ALT, ...
Gao Bin - - 2012
Left ventricular assist devices are increasingly used for long-term support in heart failure patients. To promote heart recovery, finding an optimum operating point of the pump that is appropriate for the heart function, and state of the circulatory system is important. Therefore, the baroreflex sensitivity (BRS), which reflect the state ...
Hosseini S Mehran - - 2012
Heart velocity may be influenced by gagging. The medulla oblongata receives the afferents of gag reflex. Neuronal pools of vomiting, salivation and cardiac parasympathetic fibers are very close in this area. So, their activities may be changed by spillover from each other. Using the heart rate variability (HRV) analysis, the ...
Varner Victor D - - 2012
The heart is the first functioning organ to form during development. During gastrulation, the cardiac progenitors reside in the lateral plate mesoderm but maintain close contact with the underlying endoderm. In amniotes, these bilateral heart fields are initially organized as a pair of flat epithelia that move towards the embryonic ...
Wicks April F AF Department of Epidemiology, University of Washington, Seattle, WA 98101, USA. - - 2012
We investigated the risk of sudden cardiac arrest in association with the recent loss of, or separation from, a family member or friend. Our case-crossover study included 490 apparently healthy married residents of King County, Washington, who suffered sudden cardiac arrest between 1988 and 2005. We compared exposure to spouse-reported ...
Aispuru Gualberto Rodrigo - - 2012
Hospitalized acute decompensated heart failure (ADHF) patients have high risk of thromboembolic events (TE). The aim of this study is to determine the short-term prognostic value of TE for different thrombotic biomarkers (fibrinogen; D-dimer; tissue plasminogen activator antigen, t-PA; and plasminogen-activator inhibitor type 1 antigen, PAI-1) and left ventricle echocardiographic ...
Degiovanni Anna - - 2012
The study of left atrial (LA) mechanical function during atrial fibrillation (AFib) can provide valuable information, particularly if such profiling is related to the cavity electrical substrate and conveys prognostic information. To assess if there is any relation between LA mechanical and electrical asynchrony and if such evaluation can be ...
Kato Sara - - 2012
We tested a hypothesis that an enhancement of I(Ks) may play a pivotal role in ventricular proarrhythmia under high sympathetic activity. A 2-dimensional ventricular muscle layer was prepared in rabbit hearts, and action potential signals were analyzed by optical mapping. During constant stimulation, isoproterenol (ISP, 0.1 µM) significantly shortened action ...
Govekar Henry R - - 2012
BACKGROUND: This study aimed to quantify the clinical parameters of mono- and bipolar instruments that inhibit pacemaker function. The specific aims were to quantify pacer inhibition resulting from the monopolar instrument by altering the generator power setting, the generator mode, the distance between the active electrode and the pacemaker, and ...
Jazbutyte Virginija - - 2012
MicroRNAs (miRs) are small non- coding RNA molecules controlling a plethora of biological processes such as development, cellular survival and senescence. We here determined miRs differentially regulated during cardiac postnatal development and aging. Cardiac function, morphology and miR expression profiles were determined in neonatal, 4 weeks, 6 months and 19 months old normotensive ...
van Deursen Caroline J M - - 2012
BACKGROUND: -In cardiac resynchronization therapy (CRT), optimization of left ventricular (LV) stimulation timing is often time consuming. We hypothesized that the QRS vector in the vectorcardiogram (VCG) reflects electrical interventricular dyssynchrony and that the QRS vector amplitude (VA(QRS)) halfway between that during left bundle branch block (LBBB) and LV pacing ...
Lin Fay Y - - 2012
The American College of Cardiology Appropriate Use Criteria (AUC) were developed to guide use of myocardial perfusion single-photon emission computed tomography (MPS), stress echocardiography, and cardiac computed tomographic angiography (CCTA). To date, cardiologist application of AUC from a patient-based multiprocedure perspective has not been evaluated. A Web-based survey of 15 ...
Briasoulis Alexandros - - 2012
Matrix metalloproteinases (MMPs), are proteinases that participate in extracellular matrix remodelling and degradation. Under normal physiological conditions, the activities of MMPs are regulated at the level of transcription, of activation of the pro-MMP precursor zymogens and of inhibition by endogenous inhibitors (tissue inhibitors of metalloproteinases; TIMPs). Alteration in the regulation ...
Cingolani Eugenio - - 2012
BACKGROUND: Pacemaker-dependent patients with device infection require temporary pacing while the infection is treated. External transthoracic pacing is painful and variably effective, while temporary pacing leads are susceptible to superinfection. OBJECTIVE: We sought to create a biological pacemaker delivered via venous catheters in a porcine model of complete heart block, ...
Kannt Aimo - - 2012
ADP-ribosyl cyclases (ADPRCs) catalyse the conversion of nicotinamide adenine dinucleotide to cyclic adenosine diphosphoribose (cADPR) which is a second messenger involved in Ca(2+) mobilisation from intracellular stores. Via its interaction with the ryanodine receptor Ca(2+) channel in the heart, cADPR may exert arrhythmogenic activity. To test this hypothesis, we have ...
Chablais Fabian - - 2012
Mammals respond to a myocardial infarction by irreversible scar formation. By contrast, zebrafish are able to resolve the scar and to regenerate functional cardiac muscle. It is not known how opposing cellular responses of fibrosis and new myocardium formation are spatially and temporally coordinated during heart regeneration in zebrafish. Here, ...
Kambara Takahiro - - 2012
Ischemic heart disease is the major cause of death in Western countries. CTRP9 (C1q/TNF-related protein 9) is a fat-derived plasma protein that has salutary effects on glucose metabolism and vascular function. However, the functional role of CTRP9 in ischemic heart disease has not been clarified. Here, we examined the regulation ...
Das Biswadeep - - 2012
AIMS: Oxytocin (OXT) pretreatment protects the heart during ischemia-reperfusion injury by activating ATP-dependent potassium (K(ATP)) channels. The aim of the current study was to elucidate the roles of nitric oxide synthaseNOS and myocardial biochemistry in the cardioprotective effects of OXT and ischemic preconditioning (IPC). MAIN METHODS: Male New Zealand White ...
Kopec Grzegorz - - 2012
Background: Currently, there are no data on the association between right ventricular (RV) structure and ECG changes specific for idiopathic pulmonary arterial hypertension (IPAH). Therefore, we aimed to assess the accuracy of the recommended ECG criteria for predicting RV hypertrophy (RVH) and dilation in patients with IPAH. Methods and Results: ...
Brines Laia - - 2012
AIM: Myocardial stretching is an arrhythmogenic factor. Optical techniques and mechanical uncouplers are used to study the mechanoelectric feedback. The aim of this study is to determine whether the mechanical uncouplers 2,3-butanedione monoxime and Blebbistatin hinder or modify the electrophysiological effects of acute mechanical stretch. METHODS: The ventricular fibrillation modifications ...
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