Left ventricular hypertrophy : virtuous intentions, malign consequences

NARCIS (Netherlands)

Pokharel, S; Sharma, UC; Pinto, YM

Left ventricular hypertrophy (LVH) is currently the focus of intense cardiovascular research, with the resultant rapid evolution of novel concepts relating to its exceedingly complex pathophysiology. In addition to the alterations in signal transduction and disturbances in Ca2+ homeostasis, there

Left ventricular hypertrophy: virtuous intentions, malign consequences

NARCIS (Netherlands)

Pokharel, Saraswati; Sharma, Umesh C.; Pinto, Yigal M.

2003-01-01

Left ventricular hypertrophy (LVH) is currently the focus of intense cardiovascular research, with the resultant rapid evolution of novel concepts relating to its exceedingly complex pathophysiology. In addition to the alterations in signal transduction and disturbances in Ca(2+) homeostasis, there

Effects of hydroxyl radical induced-Injury in atrial versus ventricular myocardium of dog and rabbit

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Nitisha Hiranandani

2010-09-01

Full Text Available Aim: Despite the widespread use of ventricular tissue in the investigation involving hydroxyl-radical (OH* injury, one of the most potent mediators in ischemia-reperfusion injury, little is known about the impact on atrial myocardium. In this study we thus compared the OH*-induced injury response between atrial and right ventricular muscles from both rabbits and dogs under identical experimental conditions. Methods: Small, contracting ventricular and atrial rabbit and dog trabeculae were directly exposed to OH*, and contractile properties were examined and quantified. Results: A brief OH* exposure led to transient rigor like contracture with marked elevation of diastolic tension and depression of developed force. Although the injury response showed similarities between atrial and ventricular myocardium, there were significant differences as well. In rabbit atrial muscles, the development of the contracture and its peak was much faster as compared to ventricular muscles. Also, at the peak of contracture, both rabbit and dog atrial muscles show a lesser degree of contractile dysfunction. Conclusion: These results indicate that both atrial and ventricular muscles develop a rigor like contracture after acute OH*-induced injury, and atrial muscles showed a lesser degree of contractile dysfunction. Comparison of dog versus rabbit tissue shows that the response was similar in magnitude, but slower to develop in dog tissue.

Pulmonary Hypertension Due to Left Ventricular Cardiomyopathy: Is it the Result or Cause of Disease Progression?

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Adusumalli, Srinath; Mazurek, Jeremy A

2017-12-01

The purpose of this review is to define pulmonary hypertension in the setting of left heart disease (PH-LHD), discuss its epidemiology and pathophysiology, and highlight the cause and effect relationship it has with disease progression in the setting of cardiomyopathy. Both pulmonary hypertension (PH) and heart failure are becoming increasingly common. As such, PH-LHD is now the most common form of PH. The pathophysiology of the condition relates to backward transmission of elevated left ventricular filling pressures into the pulmonary circulation and, ultimately, right ventricular (RV) strain/dysfunction. It is evident that these pathophysiologic processes are both the effect and cause of left heart disease progression. In this review, we describe the complex relationship between disease progression in left ventricular cardiomyopathy and PH-LHD. Clinicians and researchers should take note of the importance of PH-LHD and RV dysfunction to appropriately risk stratify patients and develop therapies for the condition.

Ventricular and myocardial scintiscanning: Methodical fundamentals

International Nuclear Information System (INIS)

Standke, R.; Hoer, G.; Maul, F.D.

1984-01-01

Nuclear cardiology is concerned with non invasive procedures to quantitate global and regional left ventricular function (Radionuclide ventriculography), also the imaging of vitally perfused myocardium (Myocardial scintigraphy) is achieved. A gammacamera and a minicomputer are necessary. Radionuclide ventriculography enables the analysis of global and regional time dependent left ventricular volume curves and hence the evaluation of contraction and contractility of the heart muscle. The basis is a sequence of scans covering an average heartcycle. This sequence may be produced either by first pass or equilibrium technique. Myocardial scintigraphy at rest images vital myocardium, scans immediately after exercise represent the interference of myocardial perfusion and muscle mass. The regional difference (Redistribution) between normalized exercise- and rest scans provide quantitative parameters to detect impairment of exercise-induced myocardial perfusion anomalies. The procedures of sectorial analysis of left ventricular function and myocardial perfusion are presented. (orig.) [de

The pathophysiology of heart failure.

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Kemp, Clinton D; Conte, John V

2012-01-01

Heart failure is a clinical syndrome that results when the heart is unable to provide sufficient blood flow to meet metabolic requirements or accommodate systemic venous return. This common condition affects over 5 million people in the United States at a cost of $10-38 billion per year. Heart failure results from injury to the myocardium from a variety of causes including ischemic heart disease, hypertension, and diabetes. Less common etiologies include cardiomyopathies, valvular disease, myocarditis, infections, systemic toxins, and cardiotoxic drugs. As the heart fails, patients develop symptoms which include dyspnea from pulmonary congestion, and peripheral edema and ascites from impaired venous return. Constitutional symptoms such as nausea, lack of appetite, and fatigue are also common. There are several compensatory mechanisms that occur as the failing heart attempts to maintain adequate function. These include increasing cardiac output via the Frank-Starling mechanism, increasing ventricular volume and wall thickness through ventricular remodeling, and maintaining tissue perfusion with augmented mean arterial pressure through activation of neurohormonal systems. Although initially beneficial in the early stages of heart failure, all of these compensatory mechanisms eventually lead to a vicious cycle of worsening heart failure. Treatment strategies have been developed based upon the understanding of these compensatory mechanisms. Medical therapy includes diuresis, suppression of the overactive neurohormonal systems, and augmentation of contractility. Surgical options include ventricular resynchronization therapy, surgical ventricular remodeling, ventricular assist device implantation, and heart transplantation. Despite significant understanding of the underlying pathophysiological mechanisms in heart failure, this disease causes significant morbidity and carries a 50% 5-year mortality. Copyright © 2012 Elsevier Inc. All rights reserved.

Postoperative respiratory muscle dysfunction: pathophysiology and preventive strategies.

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Sasaki, Nobuo; Meyer, Matthew J; Eikermann, Matthias

2013-04-01

Postoperative pulmonary complications are responsible for significant increases in hospital cost as well as patient morbidity and mortality; respiratory muscle dysfunction represents a contributing factor. Upper airway dilator muscles functionally resist the upper airway collapsing forces created by the respiratory pump muscles. Standard perioperative medications (anesthetics, sedatives, opioids, and neuromuscular blocking agents), interventions (patient positioning, mechanical ventilation, and surgical trauma), and diseases (lung hyperinflation, obesity, and obstructive sleep apnea) have differential effects on the respiratory muscle subgroups. These effects on the upper airway dilators and respiratory pump muscles impair their coordination and function and can result in respiratory failure. Perioperative management strategies can help decrease the incidence of postoperative respiratory muscle dysfunction. Such strategies include minimally invasive procedures rather than open surgery, early and optimal mobilizing of respiratory muscles while on mechanical ventilation, judicious use of respiratory depressant anesthetics and neuromuscular blocking agents, and noninvasive ventilation when possible.

Left ventricular heart failure and pulmonary hypertension†

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Rosenkranz, Stephan; Gibbs, J. Simon R.; Wachter, Rolf; De Marco, Teresa; Vonk-Noordegraaf, Anton; Vachiéry, Jean-Luc

2016-01-01

Abstract In patients with left ventricular heart failure (HF), the development of pulmonary hypertension (PH) and right ventricular (RV) dysfunction are frequent and have important impact on disease progression, morbidity, and mortality, and therefore warrant clinical attention. Pulmonary hypertension related to left heart disease (LHD) by far represents the most common form of PH, accounting for 65–80% of cases. The proper distinction between pulmonary arterial hypertension and PH-LHD may be challenging, yet it has direct therapeutic consequences. Despite recent advances in the pathophysiological understanding and clinical assessment, and adjustments in the haemodynamic definitions and classification of PH-LHD, the haemodynamic interrelations in combined post- and pre-capillary PH are complex, definitions and prognostic significance of haemodynamic variables characterizing the degree of pre-capillary PH in LHD remain suboptimal, and there are currently no evidence-based recommendations for the management of PH-LHD. Here, we highlight the prevalence and significance of PH and RV dysfunction in patients with both HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF), and provide insights into the complex pathophysiology of cardiopulmonary interaction in LHD, which may lead to the evolution from a ‘left ventricular phenotype’ to a ‘right ventricular phenotype’ across the natural history of HF. Furthermore, we propose to better define the individual phenotype of PH by integrating the clinical context, non-invasive assessment, and invasive haemodynamic variables in a structured diagnostic work-up. Finally, we challenge current definitions and diagnostic short falls, and discuss gaps in evidence, therapeutic options and the necessity for future developments in this context. PMID:26508169

Pathophysiologic assessment of left ventricular hypertrophy and strain in asymptomatic patients with essential hypertension

International Nuclear Information System (INIS)

Pringle, S.D.; Macfarlane, P.W.; McKillop, J.H.; Lorimer, A.R.; Dunn, F.G.

1989-01-01

To investigate the significance of the electrocardiographic (ECG) pattern of left ventricular hypertrophy and strain, two groups of asymptomatic patients with essential hypertension were compared. The patients were similar in terms of age, smoking habit, serum cholesterol and blood pressure levels, but differed in the presence (Group I, n = 23) or absence (Group II, n = 23) of the ECG pattern of left ventricular hypertrophy and strain. Group I patients had significantly more episodes of exercise-induced ST segment depression (14 versus 4, p less than 0.05) and reversible thallium perfusion abnormalities (11 of 23 versus 3 of 23, p less than 0.05) despite similar exercise capacity and absence of chest pain. Nonsustained ventricular tachycardia was detected on 24 h ambulatory ECG monitoring in two patients in Group I, but no patient in Group II. Coronary arteriography performed in 20 Group I patients demonstrated significant coronary artery disease in 8 patients. This study has shown that there is a subgroup of hypertensive patients with ECG left ventricular hypertrophy and strain who have covert coronary artery disease. This can be detected by thallium perfusion scintigraphy, and may contribute to the increased risk known to be associated with this ECG abnormality

Significance of left ventricular apical-basal muscle bundle identified by cardiovascular magnetic resonance imaging in patients with hypertrophic cardiomyopathy

OpenAIRE

Gruner, Christiane; Chan, Raymond H.; Crean, Andrew; Rakowski, Harry; Rowin, Ethan J.; Care, Melanie; Deva, Djeven; Williams, Lynne; Appelbaum, Evan; Gibson, C. Michael; Lesser, John R.; Haas, Tammy S.; Udelson, James E.; Manning, Warren J.; Siminovitch, Katherine

2017-01-01

Aims Cardiovascular magnetic resonance (CMR) has improved diagnostic and management strategies in hypertrophic cardiomyopathy (HCM) by expanding our appreciation for the diverse phenotypic expression. We sought to characterize the prevalence and clinical significance of a recently identified accessory left ventricular (LV) muscle bundle extending from the apex to the basal septum or anterior wall (i.e. apical-basal). Methods and results CMR was performed in 230 genotyped HCM patients (48 ± 15...

Left ventricular function assessment using a fast 3D gradient echo pulse sequence: comparison to standard multi-breath hold 2D steady state free precession imaging and accounting for papillary muscles and trabeculations.

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Sievers, Burkhard; Schrader, Sebastian; Rehwald, Wolfgang; Hunold, Peter; Barkhausen, Joerg; Erbel, Raimund

2011-06-01

Papillary muscles and trabeculae for ventricular function analysis are known to significantly contribute to accurate volume and mass measurements. Fast imaging techniques such as three-dimensional steady-state free precession (3D SSFP) are increasingly being used to speed up imaging time, but sacrifice spatial resolution. It is unknown whether 3D SSFP, despite its reduced spatial resolution, allows for exact delineation of papillary muscles and trabeculations. We therefore compared 3D SSFP ventricular function measurements to those measured from standard multi-breath hold two-dimensional steady-state free precession cine images (standard 2D SSFP). 14 healthy subjects and 14 patients with impaired left ventricularfunction underwent 1.5 Tesla cine imaging. A stack of short axis images covering the left ventricle was acquired with 2D SSFP and 3D SSFP. Left ventricular volumes, ejection fraction, and mass were determined. Analysis was performed by substracting papillary muscles and trabeculae from left ventricular volumes. In addition, reproducibility was assessed. EDV, ESV, EF, and mass were not significantly different between 2D SSFP and 3D SSFP (mean difference healthy subjects: -0.06 +/- 3.2 ml, 0.54 +/- 2.2 ml, -0.45 +/- 1.8%, and 1.13 +/- 0.8 g, respectively; patients: 1.36 +/- 2.8 ml, -0.15 3.5 ml, 0.86 +/- 2.5%, and 0.91 +/- 0.9 g, respectively; P > or = 0.095). Intra- and interobserver variability was not different for 2D SSFP (P > or = 0.64 and P > or = 0.397) and 3D SSFP (P > or = 0.53 and P > or = 0.47). Differences in volumes, EF, and mass measurements between 3D SSFP and standard 2D SSFP are very small, and not statistically significant. 3D SSFP may be used for accurate ventricular function assessment when papillary muscles and trabeculations are to be taken into account.

Results of Cryoenergy and Radiofrequency-Based Catheter Ablation for Treating Ventricular Arrhythmias Arising From the Papillary Muscles of the Left Ventricle, Guided by Intracardiac Echocardiography and Image Integration.

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Rivera, Santiago; Ricapito, Maria de la Paz; Tomas, Leandro; Parodi, Josefina; Bardera Molina, Guillermo; Banega, Rodrigo; Bueti, Pablo; Orosco, Agustin; Reinoso, Marcelo; Caro, Milagros; Belardi, Diego; Albina, Gaston; Giniger, Alberto; Scazzuso, Fernando

2016-04-01

Catheter radiofrequency ablation of ventricular arrhythmias (VAs) arising from the left ventricle's papillary muscles has been associated with inconsistent results. The use of cryoenergy versus radiofrequency has not been compared yet. This study compares outcomes and complications of catheter ablation of VA from the papillary muscles of the left ventricle with either cryoenergy or radiofrequency. Twenty-one patients (40±12 years old; 47% males; median ejection fraction 59±7.3%) with drug refractory premature ventricular contractions or ventricular tachycardia underwent catheter cryoablation or radiofrequency ablation. VAs were localized using 3-dimensional mapping, multidetector computed tomography, and intracardiac echocardiography, with arrhythmia foci being mapped at either the anterolateral papillary muscle or posteromedial papillary muscles of the left ventricle. Focal ablation was performed using an 8-mm cryoablation catheter or a 4-mm open-irrigated radiofrequency catheter, via transmitral approach. Acute success rate was 100% for cryoenergy (n=12) and 78% for radiofrequency (n=9; P=0.08). Catheter stability was achieved in all patients (100%) treated with cryoenergy, and only in 2 (25%) patients treated with radiofrequency (P=0.001). Incidence of multiple VA morphologies was observed in 7 patients treated with radiofrequency (77.7%), whereas none was observed in those treated with cryoenergy (P=0.001). VA recurrence at 6 months follow-up was 0% for cryoablation and 44% for radiofrequency (P=0.03). Cryoablation was associated with higher success rates and lower recurrence rates than radiofrequency catheter ablation, better catheter stability, and lesser incidence of polymorphic arrhythmias. © 2016 American Heart Association, Inc.

[Effects of dauricine on action potentials and slow inward currents of guinea pig ventricular papillary muscles].

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Li, S N; Zhang, K Y

1992-11-01

Effects of dauricine (Dau) on the action potentials (AP), the slow action potentials (SAP), and the slow inward currents (Isi) of guinea pig ventricular papillary muscles were observed by means of intracellular microelectrode and single sucrose gap voltage clamp technique. In the early stage, Dau shortened action potential duration 100 (APD100) and effective refractory period (ERP) (ERP/APD ERP, and APD20, significantly decreased action potential amplitude (APA), maximum velocity (Vmax), and overshot (OS) (ERP/APD > 1; P SAP induced by isoprenaline (P < 0.01), and remarkably inhibited Isi (P < 0.01). The results suggested that Dau exerted an inhibitory effect on Na+, Ca2+, and K+ channels.

Pulmonary Arterial Stiffness: Toward a New Paradigm in Pulmonary Arterial Hypertension Pathophysiology and Assessment.

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Schäfer, Michal; Myers, Cynthia; Brown, R Dale; Frid, Maria G; Tan, Wei; Hunter, Kendall; Stenmark, Kurt R

2016-01-01

Stiffening of the pulmonary arterial bed with the subsequent increased load on the right ventricle is a paramount feature of pulmonary hypertension (PH). The pathophysiology of vascular stiffening is a complex and self-reinforcing function of extracellular matrix remodeling, driven by recruitment of circulating inflammatory cells and their interactions with resident vascular cells, and mechanotransduction of altered hemodynamic forces throughout the ventricular-vascular axis. New approaches to understanding the cell and molecular determinants of the pathophysiology combine novel biopolymer substrates, controlled flow conditions, and defined cell types to recapitulate the biomechanical environment in vitro. Simultaneously, advances are occurring to assess novel parameters of stiffness in vivo. In this comprehensive state-of-art review, we describe clinical hemodynamic markers, together with the newest translational echocardiographic and cardiac magnetic resonance imaging methods, to assess vascular stiffness and ventricular-vascular coupling. Finally, fluid-tissue interactions appear to offer a novel route of investigating the mechanotransduction processes and disease progression.

Left ventricular hypertrophy: virtuous intentions, malign consequences.

Science.gov (United States)

Pokharel, Saraswati; Sharma, Umesh C; Pinto, Yigal M

2003-06-01

Left ventricular hypertrophy (LVH) is currently the focus of intense cardiovascular research, with the resultant rapid evolution of novel concepts relating to its exceedingly complex pathophysiology. In addition to the alterations in signal transduction and disturbances in Ca(2+) homeostasis, there are structural changes in myofilaments, disorganization of the cytoskeletal framework and increased collagen synthesis. LVH is associated with progressive left ventricular remodeling that culminates to heart failure. The modern treatment of left ventricular hypertrophy is now largely based on the hypothesis that neuroendocrine activation is important in the progression of the disease and inhibition of neurohormones is likely to have long-term benefit with regard to morbidity and mortality. Drugs specifically designed to unload the left ventricle, such as diuretics and vasodilators, appears to be less effective in reducing LV mass and improving prognosis. Thus, the evolution of treatment for LVH itself has provided much enlightenment for our understanding of the fundamental biology of the disorder.

Role of the Purkinje-Muscle Junction on the Ventricular Repolarization Heterogeneity in the Healthy and Ischemic Ovine Ventricular Myocardium

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Marine E. Martinez

2018-06-01

Full Text Available Alteration of action potential duration (APD heterogeneity contributes to arrhythmogenesis. Purkinje-muscle junctions (PMJs present differential electrophysiological properties including longer APD. The goal of this study was to determine if Purkinje-related or myocardial focal activation modulates ventricular repolarization differentially in healthy and ischemic myocardium. Simultaneous epicardial (EPI and endocardial (ENDO optical mapping was performed on sheep left ventricular (LV wedges with intact free-running Purkinje network (N = 7. Preparations were paced on either ENDO or EPI surfaces, or the free-running Purkinje fibers (PFs, mimicking normal activation. EPI and ENDO APDs were assessed for each pacing configuration, before and after (7 min of the onset of no-flow ischemia. Experiments were supported by simulations. In control conditions, maximal APD was found at endocardial PMJ sites. We observed a significant transmural APD gradient for PF pacing with PMJ APD = 347 ± 41 ms and EPI APD = 273 ± 36 ms (p < 0.001. A similar transmural gradient was observed when pacing ENDO (49 ± 31 ms; p = 0.005. However, the gradient was reduced when pacing EPI (37 ± 20 ms; p = 0.005. Global dispersion of repolarization was the most pronounced for EPI pacing. In ischemia, both ENDO and EPI APD were reduced (p = 0.005 and the transmural APD gradient (109 ± 55 ms was increased when pacing ENDO compared to control condition or when pacing EPI (p < 0.05. APD maxima remained localized at functional PMJs during ischemia. Local repolarization dispersion was significantly higher at the PMJ than at other sites. The results were consistent with simulations. We found that the activation sequence modulates repolarization heterogeneity in the ischemic sheep LV. PMJs remain active following ischemia and exert significant influence on local repolarization patterns.

Exploring energy loss by vector flow mapping in children with ventricular septal defect: Pathophysiologic significance.

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Honda, Takashi; Itatani, Keiichi; Takanashi, Manabu; Kitagawa, Atsushi; Ando, Hisashi; Kimura, Sumito; Oka, Norihiko; Miyaji, Kagami; Ishii, Masahiro

2017-10-01

Vector flow mapping is a novel echocardiographic flow visualization method, and it has enabled us to quantitatively evaluate the energy loss in the left ventricle (intraventricular energy loss). Although intraventricular energy loss is assumed to be a part of left ventricular workload itself, it is unclear what this parameter actually represents. The aim of the present study was to elucidate the characteristics of intraventricular energy loss. We enrolled 26 consecutive children with ventricular septal defect (VSD). On echocardiography vector flow mapping, intraventricular energy loss was measured in the apical 3-chamber view. We measured peak energy loss and averaged energy loss in the diastolic and systolic phases, and subsequently compared these parameters with catheterization parameters and serum brain natrium peptide (BNP) level. Diastolic, peak, and systolic energy loss were strongly and positively correlated with right ventricular systolic pressure (r=0.76, 0.68, and 0.56, p<0.0001, = 0.0001, and 0.0029, respectively) and right ventricular end diastolic pressure (r=0.55, 0.49, and 0.49, p=0.0038, 0.0120, and 0.0111, respectively). In addition, diastolic, peak, and systolic energy loss were significantly correlated with BNP (r=0.75, 0.69 and 0.49, p<0.0001, < 0.0001, and=0.0116, respectively). In children with VSD, elevated right ventricular pressure is one of the factors that increase energy loss in the left ventricle. The results of the present study encourage further studies in other study populations to elucidate the characteristics of intraventricular energy loss for its possible clinical application. Copyright © 2017 Elsevier B.V. All rights reserved.

Arrhythmogenic right ventricular dysplasia: A case report

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Tessa Negrín Valdés

2015-10-01

Full Text Available Arrhythmogenic right ventricular dysplasia is a heart muscle disease that predominantly affects the right ventricle, bringing about the replacement of normal myocardium with fatty or fibrofatty tissue and causing sudden death in young individuals. Ventricular tachycardia is an important clinical manifestation, although there are reports of right or global heart failure. The diagnosis is confirmed by echocardiography and magnetic resonance imaging. The case of a 65-year-old former smoker, with hypertension and ischemic heart disease, a history of effort syncope symptoms and proven non-sustained ventricular tachycardia, with morphology of left bundle branch block, is reported. Relevant diagnostic studies were performed, and echocardiographic elements which were compatible with arrhythmogenic right ventricular dysplasia were found. Therefore, an implantable cardioverter defibrillator was implanted, after which the patient has had a favorable outcome.

Factors related to outcome in heart failure with a preserved (or normal) left ventricular ejection fraction.

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Sanderson, John E

2016-07-01

Heart failure with a preserved ejection faction (HFpEF) is a growing and expensive cause of heart failure (HF) affecting particularly the elderly. It differs in substantial ways in addition to the normal left ventricular ejection fraction, from the more easily recognized form of heart failure with a reduced ejection fraction (HFrEF or 'systolic heart failure') and unlike HFrEF there have been little advances in treatment. In part, this relates to the complexity of the pathophysiology and identifying the correct targets. In HFpEF, there appears to be widespread stiffening of the vasculature and the myocardium affecting ventricular function (both systolic and diastolic), impeding ventricular suction, and thus early diastolic filling leading to breathlessness on exertion and later atrial failure and fibrillation. Left ventricular ejection fraction tends to gradually decline and some evolve into HFrEF. Most patients also have a mixture of several co-morbidities including hypertension, diabetes, obesity, poor renal function, lack of fitness, and often poor social conditions. Therefore, many factors may influence outcome in an individual patient. In this review, the epidemiology, possible causation, pathophysiology, the influence of co-morbidities and some of the many potential predictors of outcome will be considered.

Arrhythmogenic right ventricular dysplasia: MRI findings

International Nuclear Information System (INIS)

Wall, E.E. van der; Bootsma, M.M.; Schalij, M.J.; Kayser, H.W.M.; Roos, A. de

2000-01-01

Arrhythmogenic right ventricular dysplasia (ARVD) is a heart muscle disorder of unknown cause that is characterized pathologically by fibrofatty replacement of the right ventricular myocardium. Clinical manifestations include structural and functional malformations of the right ventricle, electrocardiographic abnormalities, and presentation with ventricular tachycardias with left bundle branch pattern or sudden death. The disease is often familial with an autosomal inheritance. In addition to right ventricular dilatation, right ventricular aneurysms are typical deformities of ARVD and they are distributed in the so-called ''triangle of dysplasia'', i. e., right ventricular outflow tract, apex, and infundibulum. Ventricular aneurysms at these sites can be considered pathognomonic of ARVD. Another typical hallmark of ARVD is fibrofatty infiltration of the right ventricular free wall. These functional and morphologic characteristics are relevant to clinical imaging investigations such as contrast angiography, echocardiography, radionuclide angiography, ultrafast computed tomography, and magnetic resonance imaging (MRI). Among these techniques, MRI allows the clearest visualization of the heart, in particular because the right ventricle is involved, which is usually more difficult to explore with the other imaging modalities. Furthermore, MRI offers the specific advantage of visualizing adipose infiltration as a bright signal of the right ventricular myocardium. MRI provides the most important anatomic, functional, and morphologic criteria for diagnosis of ARVD within one single study. As a result, MRI appears to be the optimal imaging technique for detecting and following patients with clinical suspicion of ARVD. (orig.) [de

Redox signaling in cardiovascular pathophysiology: A focus on hydrogen peroxide and vascular smooth muscle cells

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Chang Hyun Byon

2016-10-01

Full Text Available Oxidative stress represents excessive intracellular levels of reactive oxygen species (ROS, which plays a major role in the pathogenesis of cardiovascular disease. Besides having a critical impact on the development and progression of vascular pathologies including atherosclerosis and diabetic vasculopathy, oxidative stress also regulates physiological signaling processes. As a cell permeable ROS generated by cellular metabolism involved in intracellular signaling, hydrogen peroxide (H2O2 exerts tremendous impact on cardiovascular pathophysiology. Under pathological conditions, increased oxidase activities and/or impaired antioxidant systems results in uncontrolled production of ROS. In a pro-oxidant environment, vascular smooth muscle cells (VSMC undergo phenotypic changes which can lead to the development of vascular dysfunction such as vascular inflammation and calcification. Investigations are ongoing to elucidate the mechanisms for cardiovascular disorders induced by oxidative stress. This review mainly focuses on the role of H2O2 in regulating physiological and pathological signals in VSMC.

Serial Noninvasive Assessment of Apoptosis During Right Ventricular Disease Progression in Rats

NARCIS (Netherlands)

Campian, Maria E.; Verberne, Hein J.; Hardziyenka, Maxim; de Bruin, Kora; Selwaness, Mariana; van den Hoff, Maurice J. B.; Ruijter, Jan M.; van Eck-Smit, Berthe L. F.; de Bakker, Jacques M. T.; Tan, Hanno L.

2009-01-01

Right ventricular (RV) function is the major determinant of survival in patients with pulmonary hypertension. Yet, the pathophysiologic basis of RV disease is unresolved. We aimed to study the role of apoptosis in RV disease by monitoring it serially during disease progression using in vivo

Surgical myocardial revascularization in patients with reduced systolic left ventricular function.

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Bruno, Piergiorgio; Iafrancesco, Mauro; Massetti, Massimo

2018-04-20

Surgical myocardial revascularization in patients with reduced left ventricular function has been a matter of debate for decades. Recently published 10-years extension follow-up of the STICH trial have conclusively demonstrated benefit of surgical myocardial revascularization in patients with significant coronary artery disease and low left ventricular ejection fraction. However, selection of patients for surgery remains challenging as well as decision to perform percutaneous rather than surgical revascularization in this class of patients. New evidence helped to clarify the role of preoperative patients' characteristics as risk factors for surgery and to identify those patients who may benefit the most from surgery. Focus of this review is to review epidemiology, aetiology and pathophysiology of coronary artery disease in patients with reduced left ventricular function, role of viability and results of observational and investigational studies on revascularization in patients with reduced left ventricular function with a particular emphasis on relative indication of coronary artery bypass grafting and percutaneous coronary intervention and the surgical implications of development of ischemic mitral regurgitation or ischemic left ventricular aneurysm.

Impairment of Excitation-Contraction Coupling in Right Ventricular Hypertrophied Muscle with Fibrosis Induced by Pulmonary Artery Banding.

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Yoichiro Kusakari

Full Text Available Interstitial myocardial fibrosis is one of the factors responsible for dysfunction of the heart. However, how interstitial fibrosis affects cardiac function and excitation-contraction coupling (E-C coupling has not yet been clarified. We developed an animal model of right ventricular (RV hypertrophy with fibrosis by pulmonary artery (PA banding in rats. Two, four, and six weeks after the PA-banding operation, the tension and intracellular Ca2+ concentration of RV papillary muscles were simultaneously measured (n = 33. The PA-banding rats were clearly divided into two groups by the presence or absence of apparent interstitial fibrosis in the papillary muscles: F+ or F- group, respectively. The papillary muscle diameter and size of myocytes were almost identical between F+ and F-, although the RV free wall weight was heavier in F+ than in F-. F+ papillary muscles exhibited higher stiffness, lower active tension, and lower Ca2+ responsiveness compared with Sham and F- papillary muscles. In addition, we found that the time to peak Ca2+ had the highest correlation coefficient to percent of fibrosis among other parameters, such as RV weight and active tension of papillary muscles. The phosphorylation level of troponin I in F+ was significantly higher than that in Sham and F-, which supports the idea of lower Ca2+ responsiveness in F+. We also found that connexin 43 in F+ was sparse and disorganized in the intercalated disk area where interstitial fibrosis strongly developed. In the present study, the RV papillary muscles obtained from the PA-banding rats enabled us to directly investigate the relationship between fibrosis and cardiac dysfunction, the impairment of E-C coupling in particular. Our results suggest that interstitial fibrosis worsens cardiac function due to 1 the decrease in Ca2+ responsiveness and 2 the asynchronous activation of each cardiac myocyte in the fibrotic preparation due to sparse cell-to-cell communication.

A case report of arrhythmogenic right ventricular dysplasia

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Henry Anselmo Mayala

2013-01-01

Full Text Available Background Arrhythmogenic right ventricular dysplasia is an autosomal dominant disorder affecting parts of myocardium known as desmosomes, areas on the surface of heart muscle cells which link the cells together. The hallmark feature is fibro-fatty replacement of the right ventricle myocardium characterized by hypokinetic areas with associated arrhythmias originating in the right ventricle. CasePresentation Inthisreporta42yearoldmanwasadmittedatWuhanunion Hospital with the presenting complaints of visual hallucination and difficulty in breathing on exertion, with a family history of sudden death. Clinical and imaging findings are suggestive of Arrhythmogenic right ventricular dysplasia. Conclusion Despitebeingamongtherarecardiacdisease,Arrhythmogenicright ventricular dysplasia is an important cause of ventricular arrhythmias in children and young adults, it is also responsible for sudden cardiac death in the young population, making it necessary for this case report.

Pathophysiological analyses of periventricular nodular heterotopia using gyrencephalic mammals.

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Matsumoto, Naoyuki; Hoshiba, Yoshio; Morita, Kazuya; Uda, Natsu; Hirota, Miwako; Minamikawa, Maki; Ebisu, Haruka; Shinmyo, Yohei; Kawasaki, Hiroshi

2017-03-15

Although periventricular nodular heterotopia (PNH) is often found in the cerebral cortex of people with thanatophoric dysplasia (TD), the pathophysiology of PNH in TD is largely unknown. This is mainly because of difficulties in obtaining brain samples of TD patients and a lack of appropriate animal models for analyzing the pathophysiology of PNH in TD. Here we investigate the pathophysiological mechanisms of PNH in the cerebral cortex of TD by utilizing a ferret TD model which we recently developed. To make TD ferrets, we electroporated fibroblast growth factor 8 (FGF8) into the cerebral cortex of ferrets. Our immunohistochemical analyses showed that PNH nodules in the cerebral cortex of TD ferrets were mostly composed of cortical neurons, including upper layer neurons and GABAergic neurons. We also found disorganizations of radial glial fibers and of the ventricular lining in the TD ferret cortex, indicating that PNH may result from defects in radial migration of cortical neurons along radial glial fibers during development. Our findings provide novel mechanistic insights into the pathogenesis of PNH in TD. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Physiological and pathophysiological reactive oxygen species as probed by EPR spectroscopy: the underutilized research window on muscle ageing.

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A Abdel-Rahman, Engy; Mahmoud, Ali M; Khalifa, Abdulrahman M; Ali, Sameh S

2016-08-15

Reactive oxygen and nitrogen species (ROS and RNS) play crucial roles in triggering, mediating and regulating physiological and pathophysiological signal transduction pathways within the cell. Within the cell, ROS efflux is firmly controlled both spatially and temporally, making the study of ROS dynamics a challenging task. Different approaches have been developed for ROS assessment; however, many of these assays are not capable of direct identification or determination of subcellular localization of different ROS. Here we highlight electron paramagnetic resonance (EPR) spectroscopy as a powerful technique that is uniquely capable of addressing questions on ROS dynamics in different biological specimens and cellular compartments. Due to their critical importance in muscle functions and dysfunction, we discuss in some detail spin trapping of various ROS and focus on EPR detection of nitric oxide before highlighting how EPR can be utilized to probe biophysical characteristics of the environment surrounding a given stable radical. Despite the demonstrated ability of EPR spectroscopy to provide unique information on the identity, quantity, dynamics and environment of radical species, its applications in the field of muscle physiology, fatiguing and ageing are disproportionately infrequent. While reviewing the limited examples of successful EPR applications in muscle biology we conclude that the field would greatly benefit from more studies exploring ROS sources and kinetics by spin trapping, protein dynamics by site-directed spin labelling, and membrane dynamics and global redox changes by spin probing EPR approaches. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

Assessment of (patho)physiologic alterations in equine muscle metabolism

NARCIS (Netherlands)

Westermann, C.M.

2008-01-01

This thesis focussed on the diagnostic use of metabolic products and enzymes found in plasma, urine and muscle of the horse, the identification of which can reveal physiological or pathological changes in muscle metabolism. In this thesis analyses of carbohydrate-, lipid- and protein metabolites

Improved Arterial–Ventricular Coupling in Metabolic Syndrome after Exercise Training

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Fournier, Sara B.; Donley, David A.; Bonner, Daniel E.; DeVallance, Evan; Olfert, I. Mark; Chantler, Paul D.

2014-01-01

Purpose The metabolic syndrome (MetS) is associated with a three-fold increase risk of cardiovascular (CV) morbidity and mortality, which is in part, due to a blunted CV reserve capacity, reflected by a reduced peak exercise left ventricular contractility and aerobic capacity, and a blunted peak arterial-ventricular coupling. To date, no study has examined whether aerobic exercise training in MetS can reverse the peak exercise CV dysfunction. Further, examining how exercise training alters CV function in a group of individuals with MetS prior to the development of diabetes and/or overt CVD, can provide insights into whether some of the pathophysiological changes to the CV can be delayed/reversed, lowering their CV risk. The objective of this study was to examine the effects of 8 weeks of aerobic exercise training in individuals with MetS on resting and peak exercise CV function. Methods Twenty MetS underwent either 8 weeks of aerobic exercise training (MetS-ExT; n=10) or remained sedentary (MetS-NonT; n=10) during this time period. Resting and peak exercise CV function was characterized using Doppler echocardiography and gas exchange. Results Exercise training did not alter resting left ventricular diastolic or systolic function and arterial-ventricular coupling in MetS. In contrast, at peak exercise an increase in LV contractility (40%, p<0.01), cardiac output (28%, p<0.05) and aerobic capacity (20%, p<0.01), while a reduction in vascular resistance (30%, p<0.05) and arterial-ventricular coupling (27%, p<0.01), were noted in the MetS-ExT but not the MetS-NonT group. Further, an improvement in Lifetime Risk Score was also noted in the MetS-ExT group. Conclusions These findings have clinical importance as they provide insight that some of the pathophysiological changes associated with MetS can be improved and lower the risk of CVD. PMID:24870568

Intracardiac echo-facilitated 3D electroanatomical mapping of ventricular arrhythmias from the papillary muscles: assessing the 'fourth dimension' during ablation.

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Proietti, Riccardo; Rivera, Santiago; Dussault, Charles; Essebag, Vidal; Bernier, Martin L; Ayala-Paredes, Felix; Badra-Verdu, Mariano; Roux, Jean-François

2017-01-01

Ventricular arrhythmias (VA) originating from a papillary muscle (PM) have recently been described as a distinct clinical entity with peculiar features that make its treatment with catheter ablation challenging. Here, we report our experience using an intracardiac echo-facilitated 3D electroanatomical mapping approach in a case series of patients undergoing ablation for PM VA. Sixteen patients who underwent catheter ablation for ventricular tachycardia (VT) or symptomatic premature ventricular contractions originating from left ventricular PMs were included in the study. A total of 24 procedures (mean 1.5 per patient) were performed: 15 using a retrograde aortic approach and 9 using a transseptal approach. Integrated intracardiac ultrasound for 3D electroanatomical mapping was used in 15 of the 24 procedures. The posteromedial PM was the most frequent culprit for the clinical arrhythmia, and the body was the part of the PM most likely to be the successful site for ablation. The site of ablation was identified based on the best pace map matching the clinical arrhythmia and the site of earliest the activation. At a mean follow-up of 10.5 ± 7 months, only two patients had recurrent arrhythmias following a repeat ablation procedure. An echo-facilitated 3D electroanatomical mapping allows for real-time creation of precise geometries of cardiac chambers and endocavitary structures. This is useful during procedures such as catheter ablation of VAs originating from PMs, which require detailed representation of anatomical landmarks. Routine adoption of this technique should be considered to improve outcomes of PM VA ablation. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.

Resolving the True Ventricular Mural Architecture

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Robert S. Stephenson

2018-06-01

Full Text Available The precise nature of packing together of the cardiomyocytes within the ventricular walls has still to be determined. The spiraling nature of the chains of interconnected cardiomyocytes has long been recognized. As long ago as the end of the nineteenth century, Pettigrew had emphasized that the ventricular cone was not arranged on the basis of skeletal muscle. Despite this guidance, subsequent anatomists described entities such as “bulbo-spiral muscles”, with this notion of subunits culminating in the suggestion that the ventricular cone could be unwrapped so as to produce a “ventricular myocardial band”. Others, in contrast, had suggested that the ventricular walls were arranged on the basis of “sheets”, or more recently “sheetlets”, with investigators seeking to establishing the angulation of these entities using techniques such as magnetic resonance imaging. Our own investigations, in contrast, have shown that the cardiomyocytes are aggregated together within the supporting fibrous matrix so as to produce a three-dimensional myocardial mesh. In this review, we summarize the previous accounts, and provide the anatomical evidence we have thus far accumulated to support the model of the myocardial mesh. We show how these anatomic findings underscore the concept of the myocardial mesh functioning in antagonistic fashion. They lend evidence to support the notion that the ventricular myocardium works as a muscular hydrostat.

Central voice production and pathophysiology of spasmodic dysphonia.

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Mor, Niv; Simonyan, Kristina; Blitzer, Andrew

2018-01-01

Our ability to speak is complex, and the role of the central nervous system in controlling speech production is often overlooked in the field of otolaryngology. In this brief review, we present an integrated overview of speech production with a focus on the role of central nervous system. The role of central control of voice production is then further discussed in relation to the potential pathophysiology of spasmodic dysphonia (SD). Peer-review articles on central laryngeal control and SD were identified from PUBMED search. Selected articles were augmented with designated relevant publications. Publications that discussed central and peripheral nervous system control of voice production and the central pathophysiology of laryngeal dystonia were chosen. Our ability to speak is regulated by specialized complex mechanisms coordinated by high-level cortical signaling, brainstem reflexes, peripheral nerves, muscles, and mucosal actions. Recent studies suggest that SD results from a primary central disturbance associated with dysfunction at our highest levels of central voice control. The efficacy of botulinum toxin in treating SD may not be limited solely to its local effect on laryngeal muscles and also may modulate the disorder at the level of the central nervous system. Future therapeutic options that target the central nervous system may help modulate the underlying disorder in SD and allow clinicians to better understand the principal pathophysiology. NA.Laryngoscope, 128:177-183, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

Spasmodic Dysphonia: A Review. Part 2: Characterization of Pathophysiology.

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Hintze, Justin M; Ludlow, Christy L; Bansberg, Stephen F; Adler, Charles H; Lott, David G

2017-10-01

Objective The purpose of this review is to describe the recent advances in characterizing spasmodic dysphonia. Spasmodic dysphonia is a task-specific focal laryngeal dystonia characterized by irregular and uncontrolled voice breaks. The pathophysiology is poorly understood, and there are diagnostic difficulties. Data Sources PubMed, Google Scholar, and Cochrane Library. Review Methods The data sources were searched using the following search terms: ( spasmodic dysphonia or laryngeal dystonia) and ( etiology, aetiology, diagnosis, pathogenesis, or pathophysiology). Conclusion The diagnosis of spasmodic dysphonia can be difficult due to the lack of a scientific consensus on diagnostic criteria and the fact that other voice disorders may present similarly. Confusion can arise between spasmodic dysphonia and muscle tension dysphonia. Spasmodic dysphonia symptoms are tied to particular speech sounds, whereas muscle tension dysphonia is not. With the advent of more widespread use of high-speed laryngoscopy and videokymography, measures of the disruptions in phonation and delays in the onset of vocal fold vibration after vocal fold closure can be quantified. Recent technological developments have expanded our understanding of the pathophysiology of spasmodic dysphonia. Implications for Practice A 3-tiered approach, involving a questionnaire, followed by speech assessment and nasolaryngoscopy is the most widely accepted method for making the diagnosis in most cases. More experimental and invasive techniques such as electromyography and neuroimaging have been explored to further characterize spasmodic dysphonia and aid in diagnosing difficult cases.

Longitudinal strain bull's eye plot patterns in patients with cardiomyopathy and concentric left ventricular hypertrophy.

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Liu, Dan; Hu, Kai; Nordbeck, Peter; Ertl, Georg; Störk, Stefan; Weidemann, Frank

2016-05-10

Despite substantial advances in the imaging techniques and pathophysiological understanding over the last decades, identification of the underlying causes of left ventricular hypertrophy by means of echocardiographic examination remains a challenge in current clinical practice. The longitudinal strain bull's eye plot derived from 2D speckle tracking imaging offers an intuitive visual overview of the global and regional left ventricular myocardial function in a single diagram. The bull's eye mapping is clinically feasible and the plot patterns could provide clues to the etiology of cardiomyopathies. The present review summarizes the longitudinal strain, bull's eye plot features in patients with various cardiomyopathies and concentric left ventricular hypertrophy and the bull's eye plot features might serve as one of the cardiac workup steps on evaluating patients with left ventricular hypertrophy.

Muscle Weakness Is Associated With an Increase of Left Ventricular Mass Through Excessive Blood Pressure Elevation During Exercise in Patients With Hypertension.

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Kamada, Yumi; Masuda, Takashi; Tanaka, Shinya; Akiyama, Ayako; Nakamura, Takeshi; Hamazaki, Nobuaki; Okubo, Michihito; Kobayashi, Naoyuki; Ako, Junya

2017-08-03

Autonomic imbalance in hypertension induces excessive blood pressure (BP) elevation during exercise, thereby increasing left ventricular mass (LVM). Although muscle weakness enhances autonomic imbalance by stimulating muscle sympathetic activity during exercise, it is unclear whether muscle weakness is associated with an increase of LVM in patients with hypertension. This study aimed to investigate the relationships between muscle weakness, BP elevation during exercise, and LVM in these patients. Eighty-six hypertensive patients aged 69 ± 8 years with controlled resting BP (ie, exercise test performed at moderate intensity (ΔNORA and ΔPWV, respectively). A difference between baseline and peak systolic BP during the exercise test was defined as BP elevation during exercise (ΔSBP). Relationships between muscle strength, ΔNORA, ΔPWV, ΔSBP, BNP, and LVMI were analyzed, and significant factors increasing LVM were identified using univariate and multivariate regression analyses. Muscle strength was negatively correlated with ΔNORA (r = -0.202, P = 0.048), ΔPWV (r = -0.328, P = 0.002), ΔSBP (r = -0.230, P = 0.033), BNP (r = -0.265, P = 0.014), and LVMI (r = -0.233, P = 0.031). LVMI was positively correlated with ΔPWV (r = 0.246, P = 0.023) and ΔSBP (r = 0.307, P = 0.004). Muscle strength was a significant independent factor associated with LVMI (β = -0.331, P = 0.010). Our findings suggest that muscle weakness is associated with an increase of LVM through excessive BP elevation during exercise in patients with hypertension.

A case report of arrhythmogenic right ventricular dysplasia

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Henry Anselmo Mayala

2013-07-01

Full Text Available Background Arrhythmogenic right ventricular dysplasia is an autosomal dominant disorder affecting parts of myocardium known as desmosomes, areas on the surface of heart muscle cells which link the cells together. The hallmark feature is fibro-fatty replacement of the right ventricle myocardium characterized by hypokinetic areas with associated arrhythmias originating in the right ventricle. Case Presentation In this report a 42 year old man was admitted at Wuhan union Hospital with the presenting complaints of visual hallucination and difficulty in breathing on exertion, with a family history of sudden death. Clinical and imaging findings are suggestive of Arrhythmogenic right ventricular dysplasia. Conclusion Despite being among the rare cardiac disease, Arrhythmogenic right ventricular dysplasia is an important cause of ventricular arrhythmias in children and young adults, it is also responsible for sudden cardiac death in the young population, making it necessary for this case report.

Simulation Methods and Validation Criteria for Modeling Cardiac Ventricular Electrophysiology.

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Shankarjee Krishnamoorthi

Full Text Available We describe a sequence of methods to produce a partial differential equation model of the electrical activation of the ventricles. In our framework, we incorporate the anatomy and cardiac microstructure obtained from magnetic resonance imaging and diffusion tensor imaging of a New Zealand White rabbit, the Purkinje structure and the Purkinje-muscle junctions, and an electrophysiologically accurate model of the ventricular myocytes and tissue, which includes transmural and apex-to-base gradients of action potential characteristics. We solve the electrophysiology governing equations using the finite element method and compute both a 6-lead precordial electrocardiogram (ECG and the activation wavefronts over time. We are particularly concerned with the validation of the various methods used in our model and, in this regard, propose a series of validation criteria that we consider essential. These include producing a physiologically accurate ECG, a correct ventricular activation sequence, and the inducibility of ventricular fibrillation. Among other components, we conclude that a Purkinje geometry with a high density of Purkinje muscle junctions covering the right and left ventricular endocardial surfaces as well as transmural and apex-to-base gradients in action potential characteristics are necessary to produce ECGs and time activation plots that agree with physiological observations.

Simulation Methods and Validation Criteria for Modeling Cardiac Ventricular Electrophysiology.

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

2014-01-01

We describe a sequence of methods to produce a partial differential equation model of the electrical activation of the ventricles. In our framework, we incorporate the anatomy and cardiac microstructure obtained from magnetic resonance imaging and diffusion tensor imaging of a New Zealand White rabbit, the Purkinje structure and the Purkinje-muscle junctions, and an electrophysiologically accurate model of the ventricular myocytes and tissue, which includes transmural and apex-to-base gradients of action potential characteristics. We solve the electrophysiology governing equations using the finite element method and compute both a 6-lead precordial electrocardiogram (ECG) and the activation wavefronts over time. We are particularly concerned with the validation of the various methods used in our model and, in this regard, propose a series of validation criteria that we consider essential. These include producing a physiologically accurate ECG, a correct ventricular activation sequence, and the inducibility of ventricular fibrillation. Among other components, we conclude that a Purkinje geometry with a high density of Purkinje muscle junctions covering the right and left ventricular endocardial surfaces as well as transmural and apex-to-base gradients in action potential characteristics are necessary to produce ECGs and time activation plots that agree with physiological observations.

Cardiac MRI and Transthoracic Echocardiography of Left Ventricular Myocardial Noncompaction in A Patient with Congestive Heart Failure: A Case Report

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Cho, Eui Min; Byun, Joo Nam [Chosun University Hospital College of Medicine, Gwangju (Korea, Republic of); Kim, Dong Hun [Soonchunhyang University Hospital Bucheon College of Medicine, Bucheon (Korea, Republic of)

2010-11-15

We report a case of a 38-year-old male presenting with new-onset dyspnea, that was diagnosed as left ventricular noncompaction by transthoracic echocardiographic and cardiac MR. The tests revealed left ventricular systolic dysfunction with prominent trabeculations associated with deep intertrabecular recesses and an enddiastolic noncompacted to compacted ratio of 2.5 in the whole apical wall and mid-ventricular anterolateral and inferolateral walls. Delayed gadolinium contrast-enhanced MRI revealed subepicardial mid-wall hyperenhancement of the midventricular anteroseptal and inferoseptal walls, which suggested myocardial fibrosis. We review the pathophysiology, clinical characteristics, and diagnostic approach of the left ventricular noncompaction associated with congestive heart failure

Arrhythmogenic right ventricular cardiomyopathy in monozygotic twin sisters, and persistent left superior vena cava in one complicating implantation of ICD.

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Astarcıoğlu, Mehmet Ali; Yaymacı, Mehmet; Şen, Taner; Kilit, Celal; Amasyalı, Basri

2015-10-01

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited cardiomyopathy characterized histologically by fibro-fatty replacement of heart muscle, and clinically by ventricular arrhythmias and right ventricular dysfunction. This report presents monozygotic twins with ARVC, suggesting a genetic abnormality as the most probable cause.

Strength and fatigability of selected muscles in upper limb: assessing muscle imbalance relevant to tennis elbow.

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Alizadehkhaiyat, O; Fisher, A C; Kemp, G J; Frostick, S P

2007-08-01

The aetiology of tennis elbow has remained uncertain for more than a century. To examine muscle imbalance as a possible pathophysiological factor requires a reliable method of assessment. This paper describes the development of such a method and its performance in healthy subjects. We propose a combination of surface and fine-wire EMG of shoulder and forearm muscles and wrist strength measurements as a reliable tool for assessing muscle imbalance relevant to the pathophysiology of tennis elbow. Six healthy volunteers participated. EMG data were acquired at 50% maximal voluntary isometric contraction from five forearm muscles during grip and three shoulder muscles during external rotation and abduction, and analysed using normalized median frequency slope as a fatigue index. Wrist extension/flexion strength was measured using a purpose-built dynamometer. Significant negative slope of median frequency was found for all muscles, with good reproducibility, and no significant difference in slope between the different muscles of the shoulder and the wrist. (Amplitude slope showed high variability and was therefore unsuitable for this purpose.) Wrist flexion was 27+/-8% stronger than extension (mean+/-SEM, p=0.006). This is a reliable method for measuring muscle fatigue in forearm and shoulder. EMG and wrist strength studies together can be used for assessing and identifying the muscle balance in the wrist-forearm-shoulder chain.

Calcium dynamics in vascular smooth muscle

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Amberg, Gregory C.; Navedo, Manuel F.

2013-01-01

Smooth muscle cells are ultimately responsible for determining vascular luminal diameter and blood flow. Dynamic changes in intracellular calcium are a critical mechanism regulating vascular smooth muscle contractility. Processes influencing intracellular calcium are therefore important regulators of vascular function with physiological and pathophysiological consequences. In this review we discuss the major dynamic calcium signals identified and characterized in vascular smooth muscle cells....

Left Ventricular Dysfunction and Dilated Cardiomyopathy in Infants and Children with Wolff-Parkinson-White Syndrome in the Absence of Tachyarrhythmias

Science.gov (United States)

2012-01-01

Left ventricular (LV) dysfunction and dilated cardiomyopathy (DCM) are rarely attributable to sustained or incessant tachyarrhythmias in infants and children with Wolff-Parkinson-White (WPW) syndrome. However, several recent reports suggested that significant LV dysfunction may develop in WPW syndrome in the absence of tachyarrhythmias. It is assumed that an asynchronous ventricular activation over the accessory pathway, especially right-sided, induces septal wall motion abnormalities, ventricular remodeling and ventricular dysfunction. The prognosis of DCM associated with asymptomatic WPW is excellent. Loss of ventricular pre-excitation results in mechanical resynchronization and reverse remodeling where LV function recovers completely. The reversible nature of LV dysfunction after loss of ventricular pre-excitation supports the causal relationship between LV dysfunction and ventricular pre-excitation. This review summarizes recent clinical and electrophysiological evidence for development of LV dysfunction or DCM in asymptomatic WPW syndrome, and discusses the underlying pathophysiological mechanism. PMID:23323117

Mechanisms and Clinical Management of Ventricular Arrhythmias following Blunt Chest Trauma

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Daniel H. Wolbrom

2016-01-01

Full Text Available Nonpenetrating, blunt chest trauma is a serious medical condition with varied clinical presentations and implications. This can be the result of a dense projectile during competitive and recreational sports but may also include other etiologies such as motor vehicle accidents or traumatic falls. In this setting, the manifestation of ventricular arrhythmias has been observed both acutely and chronically. This is based on two entirely separate mechanisms and etiologies requiring different treatments. Ventricular fibrillation can occur immediately after chest wall injury (commotio cordis and requires rapid defibrillation. Monomorphic ventricular tachycardia can develop in the chronic stage due to underlying structural heart disease long after blunt chest injury. The associated arrhythmogenic tissue may be complex and provides the necessary substrate to form a reentrant VT circuit. Ventricular tachycardia in the absence of overt structural heart disease appears to be focal in nature with rapid termination during ablation. Regardless of the VT mechanism, patients with recurrent episodes, despite antiarrhythmic medication in the chronic stage following blunt chest injury, are likely to require ablation to achieve VT control. This review article will describe the mechanisms, pathophysiology, and treatment of ventricular arrhythmias that occur in both the acute and chronic stages following blunt chest trauma.

In-vitro experiments to characterize ventricular electromechanics

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Arnold Robert

2016-09-01

Full Text Available Computer simulation turns out to be beneficial when clinical data lack spatio-temporal resolution or parameters cannot be measured at all. To derive trustworthy results, these in-silico models have to thoroughly parameterized and validated. In this work we present data from a simplified in-vitro setup for characterizing ventricular electromechanics. Right ventricular papillary muscles from New Zealand rabbits were isolated and stretched from slack length to lmax, i.e. the muscle length at maximum active force development. Active stress development showed an almost linear increase for moderate strain (90–100% of lmax and a significant decrease for larger strain (100–105% of lmax. Passive strain development showed a nonlinear increase. Conduction velocity CV showed an increase of ≈10% between low and moderate strain and no significant decrease beyond. Fitting active active stress-strain relationship using a 5th-order polynomial yielded adequate results for moderate and high strain values, whereas fitting using a logistic function yielded more reasonable results for low strain values. Passive stress-strain relationship was satisfactorily fitted using an exponential function.

Correlation of radiological assessment of congestive heart failure with left ventricular end-diastolic pressure

International Nuclear Information System (INIS)

Herman, P.G.; Kahn, A.; Kallman, C.E.; Rojas, K.A.; Bodenheimer, M.M.

1988-01-01

Left ventricular end-diastolic pressure (LVEDP) has been considered a reliable indicator of left ventricular function. The purpose of this study was to correlate the radiologic assessment of congestive heart failure with LVEDP. The population of the study consisted of 85 consecutive cases in four ranges of LVEDP ( 24). The PA chest radiographs obtained 1 day prior to cardiac catherization were assessed for radiological evidence of congestive heart failure and were graded from normal to abnormal (0-3). The results will be summarized in the authors' presentation. The discordance of radiological assessment of congestive heart failure in patients with elevated LVEDP will be discussed in light of recent advances in pathophysiologic understanding of left ventricular function and the impact of new classes of drugs in the management of these patients

Pathophysiology of obstructive sleep apnea-hypopnea syndrome (OSAHS

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Marco Venegas-Mariño

2017-08-01

Full Text Available Obstructive sleep apnea-hypopnea syndrome (OSAHS is a disease characterized by recurrent upper airway obstruction (UAO, with decreased airflow, intermittent hypoxemia, and awakening during sleep. Two essential factors are related to the pathophysiology of OSAHS: anatomical alterations and reduction or absence of neural control. While studying OSAHS, the site or sites of obstruction of the UA should be identified; they may extend from the nasal wings to the hypopharynx. Another important factor in this syndrome is the nervous influence on muscle tone of the hypopharynx, as well as the changes in blood pH, which are secondary to micro-arousals. Body position and sleep stage determine the severity. The pathophysiology of OSAHS should be understood to properly study a patient and provide the best treatment option.

Alternative right ventricular pacing sites.

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Łuciuk, Dariusz; Łuciuk, Marek; Gajek, Jacek

2015-01-01

The main adverse effect of chronic stimulation is stimulation-induced heart failure in case of ventricular contraction dyssynchrony. Because of this fact, new techniques of stimulation should be considered to optimize electrotherapy. One of these methods is pacing from alternative right ventricular sites. The purpose of this article is to review currently accumulated data about alternative sites of cardiac pacing. Medline and PubMed bases were used to search English and Polish reports published recently. Recent studies report a deleterious effect of long term apical pacing. It is suggested that permanent apical stimulation, by omitting physiological conduction pattern with His-Purkinie network, may lead to electrical and mechanical dyssynchrony of heart muscle contraction. In the long term this pathological situation can lead to severe heart failure and death. Because of this, scientists began to search for some alternative sites of cardiac pacing to reduce the deleterious effect of stimulation. Based on current accumulated data, it is suggested that the right ventricular outflow tract, right ventricular septum, direct His-bundle or biventricular pacing are better alternatives due to more physiological electrical impulse propagation within the heart and the reduction of the dyssynchrony effect. These methods should preserve a better left ventricular function and prevent the development of heart failure in permanent paced patients. As there is still not enough, long-term, randomized, prospective, cross-over and multicenter studies, further research is required to validate the benefits of using this kind of therapy. The article should pay attention to new sites of cardiac stimulation as a better and safer method of treatment.

Fourth ventricular ependymoma with a distant intraventricular metastasis: Report of a rare case

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Sudheer Ambekar

2013-01-01

Full Text Available Ependymoma is one of the uncommon tumors of the central nervous system (CNS in the adult age group. These tumors have a distinct propensity for metastasis, both within and outside the CNS. However, dissemination at the time of first presentation and retrograde dissemination of the tumor is rare. We report the case of a patient with fourth ventricular anaplastic ependymoma who presented with left lateral ventricular metastasis which was anatomically different from the primary tumor. We describe the clinic-pathological detail of the patient and discuss the probable pathophysiological basis for this rare presentation and its significance in management of the patient.

Neonatal posthemorrhagic hydrocephalus from prematurity: pathophysiology and current treatment concepts

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Robinson, Shenandoah

2013-01-01

Object Preterm infants are at risk for perinatal complications, including germinal matrix–intraventricular hemorrhage (IVH) and subsequent posthemorrhagic hydrocephalus (PHH). This review summarizes the current understanding of the epidemiology, pathophysiology, management, and outcomes of IVH and PHH in preterm infants. Methods The MEDLINE database was systematically searched using terms related to IVH, PHH, and relevant neurosurgical procedures to identify publications in the English medical literature. To complement information from the systematic search, pertinent articles were selected from the references of articles identifed in the initial search. Results This review summarizes the current knowledge regarding the epidemiology and pathophysiology of IVH and PHH, primarily using evidence-based studies. Advances in obstetrics and neonatology over the past few decades have contributed to a marked improvement in the survival of preterm infants, and neurological morbidity is also starting to decrease. The incidence of IVH is declining, and the incidence of PHH will likely follow. Currently, approximately 15% of preterm infants who suffer severe IVH will require permanent CSF diversion. The clinical presentation and surgical management of symptomatic PHH with temporary ventricular reservoirs (ventricular access devices) and ventriculosubgaleal shunts and permanent ventriculoperitoneal shunts are discussed. Preterm infants who develop PHH that requires surgical treatment remain at high risk for other related neurological problems, including cerebral palsy, epilepsy, and cognitive and behavioral delay. This review highlights numerous opportunities for further study to improve the care of these children. Conclusions A better grasp of the pathophysiology of IVH is beginning to impact the incidence of IVH and PHH. Neonatologists conduct rigorous Class I and II studies to advance the outcomes of preterm infants. The need for well-designed multicenter trials is

Muscle function and origin of pain in fibromyalgia

DEFF Research Database (Denmark)

Bennett, R M; Jacobsen, Søren

1994-01-01

It may be concluded that both peripheral and central mechanisms may operate in the pathophysiology of both impaired muscle function and pain in FM. These mechanisms may in part be attributable to physical deconditioning and disuse of muscle secondary to the characteristic pain and fatigue so ofte...

Potassium Chloride Versus Voltage Clamp Contractures in Ventricular Muscle

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Morad, M.; Reeck, S.; Rao, M.

1981-01-01

In frog ventricle, developed tension was markedly larger in response to depolarization caused by a voltage clamp step than to depolarization induced by high concentrations of potassium chloride. Measurement of extracellular potassium activity at the surface and at the depth of muscle during the development of contractures showed that the diffusion of potassium is much slower than the spread of depolarization through the cross section of muscle. These two observations suggest that competition between the depolarizing and the negative inotropic effects of an increase in the extracellular potassium ion concentration may determine the time course and magnitude of contractile tension in heart muscle.

Skin Sodium Concentration Correlates with Left Ventricular Hypertrophy in CKD.

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Schneider, Markus P; Raff, Ulrike; Kopp, Christoph; Scheppach, Johannes B; Toncar, Sebastian; Wanner, Christoph; Schlieper, Georg; Saritas, Turgay; Floege, Jürgen; Schmid, Matthias; Birukov, Anna; Dahlmann, Anke; Linz, Peter; Janka, Rolf; Uder, Michael; Schmieder, Roland E; Titze, Jens M; Eckardt, Kai-Uwe

2017-06-01

The pathogenesis of left ventricular hypertrophy in patients with CKD is incompletely understood. Sodium intake, which is usually assessed by measuring urinary sodium excretion, has been inconsistently linked with left ventricular hypertrophy. However, tissues such as skin and muscle may store sodium. Using 23 sodium-magnetic resonance imaging, a technique recently developed for the assessment of tissue sodium content in humans, we determined skin sodium content at the level of the calf in 99 patients with mild to moderate CKD (42 women; median [range] age, 65 [23-78] years). We also assessed total body overhydration (bioimpedance spectroscopy), 24-hour BP, and left ventricular mass (cardiac magnetic resonance imaging). Skin sodium content, but not total body overhydration, correlated with systolic BP ( r =0.33, P =0.002). Moreover, skin sodium content correlated more strongly than total body overhydration did with left ventricular mass ( r =0.56, P skin sodium content is a strong explanatory variable for left ventricular mass, unaffected by BP and total body overhydration. In conclusion, we found skin sodium content to be closely linked to left ventricular mass in patients with CKD. Interventions that reduce skin sodium content might improve cardiovascular outcomes in these patients. Copyright © 2017 by the American Society of Nephrology.

Tissue-specific and substrate-specific mitochondrial bioenergetics in feline cardiac and skeletal muscles

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Christiansen, Liselotte Bruun; Dela, Flemming; Koch, Jørgen

2015-01-01

fibers. Biopsies of left ventricular cardiac muscle and soleus muscle, a type I-rich oxidative skeletal muscle, were obtained from 15 healthy domestic cats. Enzymatic activity of citrate synthase (CS), a biomarker of mitochondrial content, was measured. Mitochondrial OXPHOS capacity with various kinds...

Predictors of muscle protein synthesis after severe pediatric burns

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Objectives: Following a major burn, muscle protein synthesis rate increases but in most patients, this response is not sufficient to compensate the also elevated protein breakdown. Given the long-term nature of the pathophysiologic response to burn injury, we hypothesized that skeletal muscle prot...

Hemoglobin A1c and arterial and ventricular stiffness in older adults.

Directory of Open Access Journals (Sweden)

Susan J Zieman

Full Text Available Arterial and ventricular stiffening are characteristics of diabetes and aging which confer significant morbidity and mortality; advanced glycation endproducts (AGE are implicated in this stiffening pathophysiology. We examined the association between HbA(1c, an AGE, with arterial and ventricular stiffness measures in older individuals without diabetes.Baseline HbA(1c was measured in 830 participants free of diabetes defined by fasting glucose or medication use in the Cardiovascular Health Study, a population-based cohort study of adults aged ≥ 65 years. We performed cross-sectional analyses using baseline exam data including echocardiography, ankle and brachial blood pressure measurement, and carotid ultrasonography. We examined the adjusted associations between HbA(1c and multiple arterial and ventricular stiffness measures by linear regression models and compared these results to the association of fasting glucose (FG with like measures.HbA(1c was correlated with fasting and 2-hour postload glucose levels (r = 0.21; p<0.001 for both and positively associated with greater body-mass index and black race. In adjusted models, HbA(1c was not associated with any measure of arterial or ventricular stiffness, including pulse pressure (PP, carotid intima-media thickness, ankle-brachial index, end-arterial elastance, or left ventricular mass (LVM. FG levels were positively associated with systolic, diastolic and PP and LVM.In this sample of older adults without diabetes, HbA(1c was not associated with arterial or ventricular stiffness measures, whereas FG levels were. The role of AGE in arterial and ventricular stiffness in older adults may be better assessed using alternate AGE markers.

Association of Smoking, Sleep Apnea, and Plasma Alkalosis With Nocturnal Ventricular Arrhythmias in Men With Systolic Heart Failure

Science.gov (United States)

Shukla, Rakesh; Wexler, Laura

2012-01-01

Background: Excess sudden death due to ventricular tachyarrhythmias remains a major mode of mortality in patients with systolic heart failure. The aim of this study was to determine the association of nocturnal ventricular arrhythmias in patients with low ejection fraction heart failure. We incorporated a large number of known pathophysiologic triggers to identify potential targets for therapy to reduce the persistently high incidence of sudden death in this population despite contemporary treatment. Methods: Eighty-six ambulatory male patients with stable low (≤ 45%) ejection fraction heart failure underwent full-night attendant polysomnography and simultaneous Holter recordings. Patients were divided into groups according to the presence or absence of couplets (paired premature ventricular excitations) and ventricular tachycardia (VT) (at least three consecutive premature ventricular excitations) during sleep. Results: In multiple regression analysis, four variables (current smoking status, increased number of arousals, plasma alkalinity, and old age) were associated with VT and two variables (apnea-hypopnea index and low right ventricular ejection fraction) were associated with couplets during sleep. Conclusions: We speculate that cessation of smoking, effective treatment of sleep apnea, and plasma alkalosis could collectively decrease the incidence of nocturnal ventricular tachyarrhythmias and the consequent risk of sudden death, which remains high despite the use of β blockades. PMID:22172636

Prospects of X-ray microanalysis in the study of pathophysiology of myocardial contraction

International Nuclear Information System (INIS)

Wendt-Gallitelli, M.F.; Schwegler, M.; Holubarsch, C.; Jacob, R.; Wolburg, H.; Schlote, W.

1980-01-01

X-ray microanalysis was used to compare chemically untreated cryosections of quick-frozen myocardial tissue in 'caffeine contracture' with cryosections of normal muscle. Our goal was to find out if it is possible by this method to detect changes in the calcium compartmentalization of the myocardial cell occurring by changes in its functional state. While it is possible to quantitate calcium in the cisternae of sarcoplasmic reticulum of the control muscle preparation, calcium could never be detected in these compartments of caffeine-contracted muscles. In active microsomal fraction of ventricular myocardium it is possible to quantitate calcium and also to distinguish two components on account of their different ability to accumulate this element. The calcium content is different in the two components of the fraction. (orig.) [de

Improved arterial-ventricular coupling in metabolic syndrome after exercise training: a pilot study.

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Fournier, Sara B; Donley, David A; Bonner, Daniel E; Devallance, Evan; Olfert, I Mark; Chantler, Paul D

2015-01-01

The metabolic syndrome (MetS) is associated with threefold increased risk of cardiovascular (CV) morbidity and mortality, which is partly due to a blunted CV reserve capacity, reflected by a reduced peak exercise left ventricular (LV) contractility and aerobic capacity and a blunted peak arterial-ventricular coupling. To date, no study has examined whether aerobic exercise training in MetS can reverse peak exercise CV dysfunction. Furthermore, examining how exercise training alters CV function in a group of individuals with MetS before the development of diabetes and/or overt CV disease can provide insights into whether some of the pathophysiological CV changes can be delayed/reversed, lowering their CV risk. The objective of this study was to examine the effects of 8 wk of aerobic exercise training in individuals with MetS on resting and peak exercise CV function. Twenty participants with MetS underwent either 8 wk of aerobic exercise training (MetS-ExT, n = 10) or remained sedentary (MetS-NonT, n = 10) during this period. Resting and peak exercise CV function was characterized using Doppler echocardiography and gas exchange. Exercise training did not alter resting LV diastolic or systolic function and arterial-ventricular coupling in MetS. In contrast, at peak exercise, an increase in LV contractility (40%, P < 0.01), cardiac output (28%, P < 0.05), and aerobic capacity (20%, P < 0.01), but a reduction in vascular resistance (30%, P < 0.05) and arterial-ventricular coupling (27%, P < 0.01), were noted in the MetS-ExT but not in the MetS-NonT group. Furthermore, an improvement in lifetime risk score was also noted in the MetS-ExT group. These findings have clinical importance because they provide insight that some of the pathophysiological changes associated with MetS can be improved and can lower the risk of CV disease.

Bloqueo aurículo-ventricular de primer grado en tirotoxicosis aguda First degree atrio-ventricular block in acute thyrotoxicosis

Directory of Open Access Journals (Sweden)

Antonio R. Vilches

2004-02-01

Full Text Available El cuadro clínico de la tirotoxicosis incluye síntomas cardiovasculares variados. La taquicardia sinusal es el trastorno electrocardiográfico más frecuente y los trastornos de conducción son extremadamente raros como modo de presentación. Comunicamos un caso de bloqueo aurículo-ventricular de primer grado en una paciente con hipertiroidismo recién diagnosticado y que comenzó días antes de la consulta con un cuadro general inespecífico. Su evaluación ulterior demostró que se trataba de una tirotoxicosis aguda autoinmune, y su tratamiento con metimazol corrigió el trastorno totalmente. Se discuten los mecanismos fisiopatológicos involucrados y las implicancias clínicas desde el punto de vista del internista.Thyrotoxicosis may present with a variety of cardiovascular symptoms. Sinus tachycardia is the most frequently encountered electrocardiographic abnormality and conduction disturbances are extremely uncommon. We present a case of first degree atrio-ventricular block in a patient with newly diagnosed hyperthyroidism and discuss the underlying pathophysiological mechanisms and the clinical implications from the internist’s standpoint.

Left ventricular remodelling in chronic primary mitral regurgitation: implications for medical therapy.

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McCutcheon, Keir; Manga, Pravin

Surgical repair or replacement of the mitral valve is currently the only recommended therapy for severe primary mitral regurgitation. The chronic elevation of wall stress caused by the resulting volume overload leads to structural remodelling of the muscular, vascular and extracellular matrix components of the myocardium. These changes are initially compensatory but in the long term have detrimental effects, which ultimately result in heart failure. Understanding the changes that occur in the myocardium due to volume overload at the molecular and cellular level may lead to medical interventions, which potentially could delay or prevent the adverse left ventricular remodelling associated with primary mitral regurgitation. The pathophysiological changes involved in left ventricular remodelling in response to chronic primary mitral regurgitation and the evidence for potential medical therapy, in particular beta-adrenergic blockers, are the focus of this review.

Direct optical activation of skeletal muscle fibres efficiently controls muscle contraction and attenuates denervation atrophy.

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Magown, Philippe; Shettar, Basavaraj; Zhang, Ying; Rafuse, Victor F

2015-10-13

Neural prostheses can restore meaningful function to paralysed muscles by electrically stimulating innervating motor axons, but fail when muscles are completely denervated, as seen in amyotrophic lateral sclerosis, or after a peripheral nerve or spinal cord injury. Here we show that channelrhodopsin-2 is expressed within the sarcolemma and T-tubules of skeletal muscle fibres in transgenic mice. This expression pattern allows for optical control of muscle contraction with comparable forces to nerve stimulation. Force can be controlled by varying light pulse intensity, duration or frequency. Light-stimulated muscle fibres depolarize proportionally to light intensity and duration. Denervated triceps surae muscles transcutaneously stimulated optically on a daily basis for 10 days show a significant attenuation in atrophy resulting in significantly greater contractile forces compared with chronically denervated muscles. Together, this study shows that channelrhodopsin-2/H134R can be used to restore function to permanently denervated muscles and reduce pathophysiological changes associated with denervation pathologies.

Longitudinal Muscle Dysfunction in Achalasia Esophagus and Its Relevance

OpenAIRE

Mittal, Ravinder K; Hong, Su Jin; Bhargava, Valmik

2013-01-01

Muscularis propria of the esophagus is organized into circular and longitudinal muscle layers. Goal of this review is to summarize the role of longitudinal muscle in physiology and pathophysiology of esophageal sensory and motor function. Simultaneous manometry and ultrasound imaging that measure circular and longitudinal muscle contraction respectively reveal that during peristalsis 2 layers of the esophagus contract in perfect synchrony. On the other hand, during transient relaxation of the...

Repaired tetralogy of Fallot: the roles of cardiovascular magnetic resonance in evaluating pathophysiology and for pulmonary valve replacement decision support

Science.gov (United States)

2011-01-01

Surgical management of tetralogy of Fallot (TOF) results in anatomic and functional abnormalities in the majority of patients. Although right ventricular volume load due to severe pulmonary regurgitation can be tolerated for many years, there is now evidence that the compensatory mechanisms of the right ventricular myocardium ultimately fail and that if the volume load is not eliminated or reduced by pulmonary valve replacement the dysfunction might be irreversible. Cardiovascular magnetic resonance (CMR) has evolved during the last 2 decades as the reference standard imaging modality to assess the anatomic and functional sequelae in patients with repaired TOF. This article reviews the pathophysiology of chronic right ventricular volume load after TOF repair and the risks and benefits of pulmonary valve replacement. The CMR techniques used to comprehensively evaluate the patient with repaired TOF are reviewed and the role of CMR in supporting clinical decisions regarding pulmonary valve replacement is discussed. PMID:21251297

Na+,K+-ATPase concentration in rodent and human heart and skeletal muscle

DEFF Research Database (Denmark)

Kjeldsen, K; Bjerregaard, P; Richter, Erik

1988-01-01

rats, cardiomyopathic hamsters, and human subjects. These methods have earlier been shown to quantify the Na+,K+-ATPase concentration in muscle tissue with high accuracy. When rats were swim trained for six weeks the heart ventricular muscle Na+,K+-ATPase concentration was increased by 20% (p less than...... was increased by up to 46% (p less than 0.001) and decreased by up to 30% (p less than 0.005) after training and immobilisation respectively. Cardiomyopathic hamsters showed a reduction of 33% (p less than 0.005) in the heart ventricular Na+,K+-ATPase concentration compared with normal hamsters. This decrease...

Pompe disease: from pathophysiology to therapy and back again

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Jeong-A eLim

2014-07-01

Full Text Available Pompe disease is a lysosomal storage disorder in which acid alpha-glucosidase is deficient or absent. Deficiency of this lysosomal enzyme results in progressive expansion of glycogen-filled lysosomes in multiple tissues, with cardiac and skeletal muscle being the most severely affected. The clinical spectrum ranges from fatal hypertrophic cardiomyopathy and skeletal muscle myopathy in infants to relatively attenuated forms, which manifest as a progressive myopathy without cardiac involvement. The currently available enzyme replacement therapy proved to be successful in reversing cardiac but not skeletal muscle abnormalities. Although the overall understanding of the disease has progressed, the pathophysiology of muscle damage remains poorly understood. Lysosomal enlargement/rupture has long been considered a mechanism of relentless muscle damage in Pompe disease. In past years, it became clear that this simple view of the pathology is inadequate; the pathological cascade involves dysfunctional autophagy, a major lysosome-dependent intracellular degradative pathway. The autophagic process in Pompe skeletal muscle is affected at the termination stage - impaired autophagosomal-lysosomal fusion. Yet another abnormality in the diseased muscle is the accelerated production of large, unrelated to ageing, lipofuscin deposits - a marker of cellular oxidative damage and a sign of mitochondrial dysfunction. The massive autophagic buildup and lipofuscin inclusions appear to cause a greater effect on muscle architecture than the enlarged lysosomes outside the autophagic regions. Furthermore, the dysfunctional autophagy affects the trafficking of the replacement enzyme and interferes with its delivery to the lysosomes. Several new therapeutic approaches have been tested in Pompe mouse models: substrate reduction therapy, lysosomal exocytosis following the overexpression of transcription factor EB and a closely related but distinct factor E3, and genetic

Cross-talk between cardiac muscle and coronary vasculature.

Science.gov (United States)

Westerhof, Nico; Boer, Christa; Lamberts, Regis R; Sipkema, Pieter

2006-10-01

The cardiac muscle and the coronary vasculature are in close proximity to each other, and a two-way interaction, called cross-talk, exists. Here we focus on the mechanical aspects of cross-talk including the role of the extracellular matrix. Cardiac muscle affects the coronary vasculature. In diastole, the effect of the cardiac muscle on the coronary vasculature depends on the (changes in) muscle length but appears to be small. In systole, coronary artery inflow is impeded, or even reversed, and venous outflow is augmented. These systolic effects are explained by two mechanisms. The waterfall model and the intramyocardial pump model are based on an intramyocardial pressure, assumed to be proportional to ventricular pressure. They explain the global effects of contraction on coronary flow and the effects of contraction in the layers of the heart wall. The varying elastance model, the muscle shortening and thickening model, and the vascular deformation model are based on direct contact between muscles and vessels. They predict global effects as well as differences on flow in layers and flow heterogeneity due to contraction. The relative contributions of these two mechanisms depend on the wall layer (epi- or endocardial) and type of contraction (isovolumic or shortening). Intramyocardial pressure results from (local) muscle contraction and to what extent the interstitial cavity contracts isovolumically. This explains why small arterioles and venules do not collapse in systole. Coronary vasculature affects the cardiac muscle. In diastole, at physiological ventricular volumes, an increase in coronary perfusion pressure increases ventricular stiffness, but the effect is small. In systole, there are two mechanisms by which coronary perfusion affects cardiac contractility. Increased perfusion pressure increases microvascular volume, thereby opening stretch-activated ion channels, resulting in an increased intracellular Ca2+ transient, which is followed by an increase in Ca

[Diagnosis and therapy of arrhythmogenic right ventricular cardiomyopathy].

Science.gov (United States)

Zorzi, Alessandro; Rigato, Ilaria; Migliore, Federico; Perazzolo Marra, Martina; Basso, Cristina; Thiene, Gaetano; Bauce, Barbara; Corrado, Domenico

2014-11-01

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart muscle disease that predisposes to the occurrence of ventricular arrhythmias and sudden death, particularly in the young and athlete. The classic variant of the disease predominantly affects the right ventricle, but phenotypic variants with early and prevalent left ventricular involvement ("left-dominant" ARVC) have also been described, supporting the concept that arrhythmogenic cardiomyopathy is a disease of both ventricles. The diagnosis is multiparametric and is based on a series of criteria, including ECG abnormalities, arrhythmic manifestations, morpho-functional abnormalities and genetic defects. The main goal of therapy is sudden death prevention. Implant of a cardioverter-defibrillator is the most effective strategy for prevention of sudden death, but it should be reserved to selected patients after accurate risk stratification, in view of the high complication rate over a long-term follow-up, the costs and the significant psychological impact of such therapy, especially in the young individual. The other therapies (either pharmacological or not) are palliative and aimed at relieving symptoms and preventing disease progression. The definitive cure of ARVC will be based on the discovery of the molecular mechanisms that are involved in the etiology and pathogenesis of the disease.

Diaphragm muscle fiber dysfunction in chronic obstructive pulmonary disease: toward a pathophysiological concept.

NARCIS (Netherlands)

Ottenheijm, C.A.C.; Heunks, L.M.A.; Dekhuijzen, P.N.R.

2007-01-01

Inspiratory muscle weakness in patients with chronic obstructive pulmonary disease (COPD) is of major clinical relevance; maximum inspiratory pressure generation is an independent determinant of survival in severe COPD. Traditionally, inspiratory muscle weakness has been ascribed to

Taquicardia ventricular del tracto de salida del ventrículo derecho durante el embarazo Right ventricular outflow tachycardia during pregnancy

Directory of Open Access Journals (Sweden)

Ariel K. Saad

2012-06-01

Full Text Available Durante el embarazo aumentan el metabolismo basal, el consumo de O2, la frecuencia cardíaca, el volumen sistólico, el volumen minuto y la volemia y disminuyen la tensión arterial y la resistencia periférica. Diferentes estudios han demostrado que durante este período la posibilidad de que ocurra una arritmia cardíaca o se produzca la exacerbación de una arritmia preexistente es mayor. No obstante, en su enorme mayoría carecen de importancia pronóstica tanto para la madre como para el feto. La taquicardia ventricular del tracto de salida del ventrículo derecho es una arritmia poco frecuente y su aparición se ha correlacionado con el aumento del tono adrenérgico. Se presentan los casos de dos pacientes que mostraron en el curso de la gestación reiterados episodios de taquicardia ventricular del tracto de salida del ventrículo derecho. Se analiza la asociación del embarazo con la ocurrencia de trastornos del ritmo cardíaco.During pregnancy, there is an increase in metabolism, oxygen consumption, heart rate, stroke volume, cardiac output, blood volume and a decrease in blood pressure and peripheral resistance. Studies have shown that during this period the occurrence of cardiac arrhythmias is not uncommon. Fortunately, malignant arrhythmias are rare. Herein we report two young patients who presented with symptomatic right ventricular outflow tachycardia during pregnancy that required antiarrhythmic therapy. Possible pathophysiologic mechanisms are discussed.

Comparison of stroke work between repaired tetralogy of Fallot and normal right ventricular physiologies.

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Lee, Namheon; Das, Ashish; Banerjee, Rupak K; Gottliebson, William M

2013-01-01

Adult patients who underwent tetralogy of Fallot repair surgery (rTOF) confront life-threatening ailments due to right ventricular (RV) myocardial dysfunction. Pulmonary valve replacement (PVR) needs to be performed to restore the deteriorating RV function. Determination of correct timing to perform PVR in an rTOF patient remains subjective, due to the unavailability of quantifiable clinical diagnostic parameters. The objective of this study is to evaluate the possibility of using RV body surface area (BSA)-indexed stroke work (SW(I)) to quantify RV inefficiency in TOF patients. We hypothesized that RV SW(I) required to push blood to the lungs in rTOF patients is significantly higher than that of normal subjects. Seven patients with rTOF pathophysiology and eight controls with normal RV physiology were registered for this study. Right ventricular volume and pressure were measured using cardiac magnetic resonance imaging and catheterization, respectively. Statistical analysis was performed to quantify the difference in SW(I) between the RV of the rTOF and control groups. Right ventricular SW(I) in rTOF patients (0.176 ± 0.055 J/m(2)) was significantly higher by 93.4% (P = 0.0026) than that of controls (0.091 ± 0.030 J/m(2)). Further, rTOF patients were found to have significantly higher (P < 0.05) BSA normalized RV end-systolic volume, end-systolic pressure, and regurgitation fraction than control subjects. Ejection fraction and peak ejection rate of rTOF patients were significantly lower (P < 0.05) than those of controls. Patients with rTOF pathophysiology had significantly higher RV SW(I) compared with subjects with normal RV physiology. Therefore, RV SW(I) may be useful to quantify RV inefficiency in rTOF patients along with currently used clinical end points such as RV volume, pressure, regurgitation fraction, and ejection fraction.

Physiology and pathophysiology of K(ATP) channels in the pancreas and cardiovascular system: a review.

Science.gov (United States)

Seino, Susumu

2003-01-01

K(ATP) channels are present in pancreatic and extrapancreatic tissues such as heart and smooth muscle, and display diverse molecular composition. They contain two different structural subunits: an inwardly rectifying potassium channel subunit (Kir6.x) and a sulfonylurea receptor (SURX). Recent studies on genetically engineered Kir6.2 knockout mice have provided a better understanding of the physiological and pathophysiological roles of Kir6.2-containing K(ATP) channels. Kir6.2/SUR1 has a pivotal role in pancreatic insulin secretion. Kir6.2/SUR2A mediates the effects of K(ATP) channels openers on cardiac excitability and contractility and contributes to ischemic preconditioning. However, controversy remains on the physiological properties of the K(ATP) channels in vascular smooth muscle cells. Kir6.1 knockout mice exhibit sudden cardiac death due to cardiac ischemia, indicating that Kir6.1 rather than Kir6.2 is critical in the regulation of vascular tone. This article summarizes current understanding of the physiology and pathophysiology of Kir6.1- and Kir6.2-containing K(ATP) channels.

Anterolateral papillary muscle rupture after intervention of the right coronary artery.

Science.gov (United States)

Morris, Liam; Desai, Anand; Akkus, Nuri Ilker

2015-11-01

Rupture of the anterolateral papillary muscle following a right coronary artery occlusion is extremely rare, and when complicated by a right ventricular infarction, can be fatal. The literature on optimal management of this complication is limited. We present an unusual case of anterolateral papillary muscle rupture following intervention of the right coronary artery. Published by Elsevier España.

Animal models of arrhythmogenic right ventricular cardiomyopathy: what have we learned and where do we go? Insight for therapeutics.

Science.gov (United States)

Padrón-Barthe, Laura; Domínguez, Fernando; Garcia-Pavia, Pablo; Lara-Pezzi, Enrique

2017-09-01

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare genetically-determined cardiac heart muscle disorder characterized by fibro-fatty replacement of the myocardium that results in heart failure and sudden cardiac death (SCD), predominantly in young males. The disease is often caused by mutations in genes encoding proteins of the desmosomal complex, with a significant minority caused by mutations in non-desmosomal proteins. Existing treatment options are based on SCD prevention with the implantable cardioverter defibrillator, antiarrhythmic drugs, and anti-heart failure medication. Heart transplantation may also be required and there is currently no cure. Several genetically modified animal models have been developed to characterize the disease, assess its progression, and determine the influence of potential environmental factors. These models have also been very valuable for translational therapeutic approaches, to screen new treatment options that prevent and/or reverse the disease. Here, we review the available ARVC animal models reported to date, highlighting the most important pathophysiological findings and discussing the effect of treatments tested so far in this setting. We also describe gaps in our knowledge of the disease, with the goal of stimulating research and improving patient outcomes.

Examination of mitral regurgitation with a goat heart model for the development of intelligent artificial papillary muscle.

Science.gov (United States)

Shiraishi, Y; Yambe, T; Yoshizawa, M; Hashimoto, H; Yamada, A; Miura, H; Hashem, M; Kitano, T; Shiga, T; Homma, D

2012-01-01

Annuloplasty for functional mitral or tricuspid regurgitation has been made for surgical restoration of valvular diseases. However, these major techniques may sometimes be ineffective because of chamber dilation and valve tethering. We have been developing a sophisticated intelligent artificial papillary muscle (PM) by using an anisotropic shape memory alloy fiber for an alternative surgical reconstruction of the continuity of the mitral structural apparatus and the left ventricular myocardium. This study exhibited the mitral regurgitation with regard to the reduction in the PM tension quantitatively with an originally developed ventricular simulator using isolated goat hearts for the sophisticated artificial PM. Aortic and mitral valves with left ventricular free wall portions of isolated goat hearts (n=9) were secured on the elastic plastic membrane and statically pressurized, which led to valvular leaflet-papillary muscle positional change and central mitral regurgitation. PMs were connected to the load cell, and the relationship between the tension of regurgitation and PM tension were measured. Then we connected the left ventricular specimen model to our hydraulic ventricular simulator and achieved hemodynamic simulation with the controlled tension of PMs.

Evaluation of left ventricular volumes in patients with congenital heart disease and abnormal left ventricular geometry. Comparison of MRI and transthoracic 3-dimensional echocardiography

International Nuclear Information System (INIS)

Gutberlet, M.; Grothoff, M.; Roettgen, R.; Lange, P.; Felix, R.; Abdul-Khaliq, H.; Schroeter, J.; Schmitt, B.; Vogel, M.

2003-01-01

Purpose: To assess the new method of 3-dimensional echocardiography in comparison to the 'gold standard' MRI as to its ability to calculate left ventricular volumes in patients with congenital heart disease. Materials and methods: Eighteen patients between the ages of 3.9 to 37.3 years (mean: 12.8±9.7) with a geometrically abnormal left ventricle were examined using a 1.5 T scanner with a fast gradient-echo sequence (TR=14 ms, TE=2.6-2.9 ms, FOV=300-400 mm, flip angle=20 , matrix=128:256, slice thickness=5 mm, retrospective gating) in multislice-multiphase technique. Transthoracic 3D-echocardiography was performed with a 3.5 MHz transducer and a Tomtec trademark (Munich, Germany) system for 3D reconstruction. Results: Volume calculation was possible in all patients with 3D-echocardiography, but the muscle mass calculation only succeeded in 11 to 18 patients (61%) due to inadequate visualization of the entire myocardium. Comparing MRI and 3D-echocardiography, the correlation was r=0.97 for the end-systolic volumes, r=0.98 for the end-diastolic volumes, r=0.79 for the end-systolic muscle mass and r=0.77 for the end-diastolic muscle mass. The agreement between both methods was considered good for the calculated end-diastolic volumes and sufficient for the calculated end-systolic volumes. The muscle mass calculations showed larger differences especially for the end-systolic mass. Mean intraobserver variability was 18.6% for end-systolic and 8.3% for end-diastolic volumes. Conclusion: In patients with an abnormal left ventricular configuration due to congenital heart disease, the new method of 3D-echocardiography is sufficient for volume calculations in preselected patients. The high intraobserver variability is still a limitation of transthoracic 3D-echocardiography in comparison to MRI. (orig.) [de

Channel sialic acids limit hERG channel activity during the ventricular action potential.

Science.gov (United States)

Norring, Sarah A; Ednie, Andrew R; Schwetz, Tara A; Du, Dongping; Yang, Hui; Bennett, Eric S

2013-02-01

Activity of human ether-a-go-go-related gene (hERG) 1 voltage-gated K(+) channels is responsible for portions of phase 2 and phase 3 repolarization of the human ventricular action potential. Here, we questioned whether and how physiologically and pathophysiologically relevant changes in surface N-glycosylation modified hERG channel function. Voltage-dependent hERG channel gating and activity were evaluated as expressed in a set of Chinese hamster ovary (CHO) cell lines under conditions of full glycosylation, no sialylation, no complex N-glycans, and following enzymatic deglycosylation of surface N-glycans. For each condition of reduced glycosylation, hERG channel steady-state activation and inactivation relationships were shifted linearly by significant depolarizing ∼9 and ∼18 mV, respectively. The hERG window current increased significantly by 50-150%, and the peak shifted by a depolarizing ∼10 mV. There was no significant change in maximum hERG current density. Deglycosylated channels were significantly more active (20-80%) than glycosylated controls during phases 2 and 3 of action potential clamp protocols. Simulations of hERG current and ventricular action potentials corroborated experimental data and predicted reduced sialylation leads to a 50-70-ms decrease in action potential duration. The data describe a novel mechanism by which hERG channel gating is modulated through physiologically and pathophysiologically relevant changes in N-glycosylation; reduced channel sialylation increases hERG channel activity during the action potential, thereby increasing the rate of action potential repolarization.

Human Pathophysiological Adaptations to the Space Environment

Directory of Open Access Journals (Sweden)

Gian C. Demontis

2017-08-01

Full Text Available Space is an extreme environment for the human body, where during long-term missions microgravity and high radiation levels represent major threats to crew health. Intriguingly, space flight (SF imposes on the body of highly selected, well-trained, and healthy individuals (astronauts and cosmonauts pathophysiological adaptive changes akin to an accelerated aging process and to some diseases. Such effects, becoming manifest over a time span of weeks (i.e., cardiovascular deconditioning to months (i.e., loss of bone density and muscle atrophy of exposure to weightlessness, can be reduced through proper countermeasures during SF and in due time are mostly reversible after landing. Based on these considerations, it is increasingly accepted that SF might provide a mechanistic insight into certain pathophysiological processes, a concept of interest to pre-nosological medicine. In this article, we will review the main stress factors encountered in space and their impact on the human body and will also discuss the possible lessons learned with space exploration in reference to human health on Earth. In fact, this is a productive, cross-fertilized, endeavor in which studies performed on Earth yield countermeasures for protection of space crew health, and space research is translated into health measures for Earth-bound population.

Pathophysiology, diagnosis, and treatment of canine hip dysplasia

International Nuclear Information System (INIS)

Cook, J.L.; Tomlinson, J.L.; Constantinescu, G.M.

1996-01-01

Dogs with hip dysplasia are commonly presented to veterinarians for evaluation. Although many causes of the condition have been proposed, a definitive cause has not been established. The multifactorial nature of canine hip dysplasia can confuse client education and management ofthe disease. The basic concept involved is the biomechanical imbalance between the forces on the coxofemoral joint and the associated muscle mass; the result is joint laxity in young, growing dogs. This laxity leads to incongruity; the eventual result is degenerative joint disease. Canine hip dysplasia can affect any breed but is most often reported in large and giant breeds. Understanding the pathophysiology and biomechanics involved with this developmental disease is important in providing clients with diagnostic, therapeutic, and prognostic information. The selection of treatment is influenced by the following factors:the age, health, and intended use of the patient; clinical signs; diagnostic findings; the availability of treatment; and the financial constraints of the owner. This article discusses the current concepts concerning the pathophysiology and biomechanics of canine hip dysplasia and outlines diagnostic and therapeutic options. The objective of the article is to provide practitioners with a reference for decision making and client education

MRI findings of muscle involvement in idiopathic hypereosinophilic syndrome

International Nuclear Information System (INIS)

Hundt, W.; Staebler, A.; Reiser, M.

1999-01-01

A 40-year-old white man presented with fever, muscle pain, skin nodules and persistent hypereosinophilia over a period of 1 year. In addition, he had ventricular arrhythmias with episodes of tachycardia. Besides a lack of response to antiparasitic therapy, laboratory and pathological data excluded the diagnosis of trichinosis or any other parasitic infection. The patient's course of the disease over the previous 1 1 / 2 years was compatible with hypereosinophilic syndrome. In a muscle biopsy several eosinophilic perivascular and leucocytic intravascular infiltrates were found, indicative of muscle involvement by the disease. This is a report on the MRI findings of muscle involvement in idiopathic hypereosinophilic syndrome. (orig.)

Catheter-based intervention for symptomatic patient with severe mitral regurgitation and very poor left ventricular systolic function - Safe but no room for complacency.

Science.gov (United States)

Loh, Poay Huan; Bourantas, Christos V; Chan, Pak Hei; Ihlemann, Nikolaj; Gustafsson, Fin; Clark, Andrew L; Price, Susanna; Mario, Carlo Di; Moat, Neil; Alamgir, Farqad; Estevez-Loureiro, Rodrigo; Søndergaard, Lars; Franzen, Olaf

2015-11-26

Many patients with left ventricular systolic dysfunction have concomitant mitral regurgitation (MR). Their symptoms and prognosis worsen with increasing severity of MR. Percutaneous MitraClip(®) can be used safely to reduce the severity of MR even in patients with advanced heart failure and is associated with improved symptoms, quality of life and exercise tolerance. However, a few patients with very poor left ventricular systolic function may experience significant haemodynamic disturbance in the peri-procedural period. We present three such patients, highlighting some of the potential problems encountered and discuss their possible pathophysiological mechanisms and safety measures.

The importance of obstructive sleep apnoea and hypopnea pathophysiology for customized therapy.

Science.gov (United States)

Bosi, Marcello; De Vito, Andrea; Gobbi, Riccardo; Poletti, Venerino; Vicini, Claudio

2017-03-01

The objective of this study is to highlight the importance of anatomical and not-anatomical factors' identification for customized therapy in OSAHS patients. The data sources are: MEDLINE, The Cochrane Library and EMBASE. A systematic review was performed to identify studies that analyze the role of multiple interacting factors involved in the OSAHS pathophysiology. 85 out of 1242 abstracts were selected for full-text review. A variable combinations pathophysiological factors contribute to realize differentiated OSAHS phenotypes: a small pharyngeal airway with a low resistance to collapse (increased critical closing pressure), an inadequate responses of pharyngeal dilator muscles (wakefulness drive to breathe), an unstable ventilator responsiveness to hypercapnia (high loop gain), and an increased propensity to wake related to upper airway obstruction (low arousal threshold). Identifying if the anatomical or not-anatomical factors are predominant in each OSAHS patient represents the current challenge in clinical practice, moreover for the treatment decision-making. In the future, if a reliable and accurate pathophysiological pattern for each OSAHS patient can be identified, a customized therapy will be feasible, with a significant improvement of surgical success in sleep surgery and a better understanding of surgical failure.

Predictors of muscle protein synthesis after severe pediatric burns.

Science.gov (United States)

Diaz, Eva C; Herndon, David N; Lee, Jinhyung; Porter, Craig; Cotter, Matthew; Suman, Oscar E; Sidossis, Labros S; Børsheim, Elisabet

2015-04-01

Following a major burn, skeletal muscle protein synthesis rate increases but is often insufficient to compensate for massively elevated muscle protein breakdown rates. Given the long-term nature of the pathophysiologic response to burn injury, we hypothesized that muscle protein synthesis rate would be chronically elevated in severely burned children. The objectives of this study were to characterize muscle protein synthesis rate of burned children over a period of 24 months after injury and to identify predictors that influence this response. A total of 87 children with 40% or greater total body surface area (TBSA) burned were included. Patients participated in stable isotope infusion studies at 1, 2, and approximately 4 weeks after burn and at 6, 12, and 24 months after injury to determine skeletal muscle protein fractional synthesis rate. Generalized estimating equations with log link normal distribution were applied to account for clustering of patients and control for patient characteristics. Patients (8 ± 6 years) had large (62, 51-72% TBSA) and deep (47% ± 21% TBSA third degree) burns. Muscle protein fractional synthesis rate was elevated throughout the first 12 months after burn compared with established values from healthy young adults. Muscle protein fractional synthesis rate was lower in boys, in children older than 3 years, and when burns were greater than 80% TBSA. Muscle protein synthesis is elevated for at least 1 year after injury, suggesting that greater muscle protein turnover is a component of the long-term pathophysiologic response to burn trauma. Muscle protein synthesis is highly affected by sex, age, and burn size in severely burned children. These findings may explain the divergence in net protein balance and lean body mass in different populations of burn patients. Prognostic study, level III.

Diffusion tensor imaging of left ventricular remodeling in response to myocardial infarction in the mouse

NARCIS (Netherlands)

Strijkers, Gustav J.; Bouts, Annemiek; Blankesteijn, W. Matthijs; Peeters, Tim H. J. M.; Vilanova, Anna; van Prooijen, Mischa C.; Sanders, Honorius M. H. F.; Heijman, Edwin; Nicolay, Klaas

2009-01-01

The cardiac muscle architecture lies at the basis of the mechanical and electrical properties of the heart, and dynamic alterations in fiber structure are known to be of prime importance in healing and remodeling after myocardial infarction. In this study, left ventricular remodeling was

Angiographic determination of the left-ventricular myocardial volume with the help of digital image processing

International Nuclear Information System (INIS)

Radtke, W.

1981-01-01

In this paper, digital image processing could for the first time be introduced as a new method to screen the myocardium in the left-ventricular angiocardiography. The method makes a reliable quantitative determination of the muscle mass of the left ventricle possible. (orig./MG) [de

Ventricular tachyarrhythmia-related basal cardiomyopathy in rabbits with vagal stimulation--a novel experimental model for inverted Takotsubo-like cardiomyopathy.

Science.gov (United States)

Takato, Tetsuya; Ashida, Terunao; Seko, Yoshinori; Fujii, Jun; Kawai, Sachio

2010-07-01

Electrical stimulation of the intact (unsectioned) cervical vagus in rabbits frequently provokes ventricular tachyarrhythmias that are often accompanied by mitral regurgitation. Unique pathological lesions often arise on the mitral valve, papillary muscles, and mitral annulus (mitral complex), the latter two of which become swollen and stiffened. These lesions are reversible in nature. Previous studies have essentially ignored the basal portion except for the mitral annulus. Therefore, the present study examined pathological lesions on the left ventricular basal portion in rabbits. The intact right vagal nerves of 20 anesthetized rabbits were repeatedly electrically stimulated under electrocardiographic monitoring. Colloidal carbon (lml) was injected intravenously immediately after the end of the stimulation and all animals were killed 1 week later. Pathological lesions were identified as carbon deposits visible at gross examination. Ventricular bigeminy was induced after vagal stimulation in 15 (75%) of the 20 rabbits. Pathological lesions were evident on the basal portion in 16 (80%) and on the mitral valve and papillary muscles of 15 (75%) of the 20 rabbits. Ventricular bigeminy was closely associated with the development of the pathological lesions, which were rarely observed on the ventricular apex. Cardiomyopathic lesions involving the basal portion and mitral complex were frequently induced in rabbits by vagal stimulation. These lesions bear a close similarity in distribution and reversibility to inverted Takotsubo cardiomyopathy. Copyright 2010 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Surgical ablation of ventricular tachycardia secondary to congenital ventricular septal aneurysm.

Science.gov (United States)

Graffigna, A; Minzioni, G; Ressia, L; Vigano, M

1994-04-01

Three patients underwent surgical ablation for ventricular tachycardia resulting from an aneurysm of the membranous portion of the ventricular septum. Two patients had a definite history of cardiac murmur during infancy, and one of them was found at the time of operation to have a left-to-right shunt through the apex of the aneurysm. The earliest ventricular activation sites were located around the neck of the aneurysm and were ablated in 1 patient by encircling the endocardial ventriculotomy and by cryoablation in the remaining 2. After focus resection had been completed, aneurysm resection and ventricular septal reconstruction were performed. All patients were alive and free of ventricular tachycardia and did not need medication as of 61, 66, and 88 months postoperatively. Spontaneous closure of a ventricular septal defect may lead to the formation of an aneurysm in the ventricular septum that may sustain ventricular tachycardias. Such arrhythmias can be effectively treated using electrically guided surgical techniques.

The Pathophysiology of Insomnia

Science.gov (United States)

Levenson, Jessica C.; Kay, Daniel B.

2015-01-01

Insomnia disorder is characterized by chronic dissatisfaction with sleep quantity or quality that is associated with difficulty falling asleep, frequent nighttime awakenings with difficulty returning to sleep, and/or awakening earlier in the morning than desired. Although progress has been made in our understanding of the nature, etiology, and pathophysiology of insomnia, there is still no universally accepted model. Greater understanding of the pathophysiology of insomnia may provide important information regarding how, and under what conditions, the disorder develops and is maintained as well as potential targets for prevention and treatment. The aims of this report are (1) to summarize current knowledge on the pathophysiology of insomnia and (2) to present a model of the pathophysiology of insomnia that considers evidence from various domains of research. Working within several models of insomnia, evidence for the pathophysiology of the disorder is presented across levels of analysis, from genetic to molecular and cellular mechanisms, neural circuitry, physiologic mechanisms, sleep behavior, and self-report. We discuss the role of hyperarousal as an overarching theme that guides our conceptualization of insomnia. Finally, we propose a model of the pathophysiology of insomnia that integrates the various types of evidence presented. PMID:25846534

Contribution of denervated muscle to contractures after neonatal brachial plexus injury: not just muscle fibrosis.

Science.gov (United States)

Nikolaou, Sia; Liangjun, Hu; Tuttle, Lori J; Weekley, Holly; Christopher, Wylie; Lieber, Richard L; Cornwall, Roger

2014-03-01

We investigated the contribution of muscle fibrosis to elbow flexion contractures in a murine model of neonatal brachial plexus injury (NBPI). Four weeks after NBPI, biceps and brachialis fibrosis were assessed histologically and compared with the timing of contracture development and the relative contribution of each muscle to contractures. Modulus of elasticity and hydroxyproline (collagen) content were measured and correlated with contracture severity. The effect of halofuginone antifibrotic therapy on fibrosis and contractures was investigated. Elbow contractures preceded muscle fibrosis development. The brachialis was less fibrotic than the biceps, yet contributed more to contractures. Modulus and hydroxyproline content increased in both elbow flexors, but neither correlated with contracture severity. Halofuginone reduced biceps fibrosis but did not reduce contracture severity. Contractures after NBPI cannot be explained solely by muscle fibrosis, arguing for investigation of alternate pathophysiologic targets for contracture prevention and treatment. Copyright © 2013 Wiley Periodicals, Inc.

MRI findings of muscle involvement in idiopathic hypereosinophilic syndrome

Energy Technology Data Exchange (ETDEWEB)

Hundt, W.; Staebler, A.; Reiser, M. [Department of Diagnostic Radiology, Klinikum Grosshadern, Muenchen (Germany)

1999-04-01

A 40-year-old white man presented with fever, muscle pain, skin nodules and persistent hypereosinophilia over a period of 1 year. In addition, he had ventricular arrhythmias with episodes of tachycardia. Besides a lack of response to antiparasitic therapy, laboratory and pathological data excluded the diagnosis of trichinosis or any other parasitic infection. The patient`s course of the disease over the previous 1{sup 1}/{sub 2} years was compatible with hypereosinophilic syndrome. In a muscle biopsy several eosinophilic perivascular and leucocytic intravascular infiltrates were found, indicative of muscle involvement by the disease. This is a report on the MRI findings of muscle involvement in idiopathic hypereosinophilic syndrome. (orig.) With 3 figs., 25 refs.

Role of renal vascular potassium channels in physiology and pathophysiology

DEFF Research Database (Denmark)

Salomonsson, Max; Brasen, Jens Christian; Sorensen, Charlotte Mehlin

2017-01-01

The control of renal vascular tone is important for the regulation of salt and water balance, blood pressure and the protection against damaging elevated glomerular pressure. The K+ conductance is a major factor in the regulation of the membrane potential (Vm ) in vascular smooth muscle (VSMC...... the ambiguous in vitro and in vivo results. We discuss the role of single types of K+ channels and the integrated function of several classes. We also deal with the possible role of renal vascular K+ channels in the pathophysiology of hypertension, diabetes mellitus and sepsis. This article is protected...

Gait post-stroke: Pathophysiology and rehabilitation strategies.

Science.gov (United States)

Beyaert, C; Vasa, R; Frykberg, G E

2015-11-01

We reviewed neural control and biomechanical description of gait in both non-disabled and post-stroke subjects. In addition, we reviewed most of the gait rehabilitation strategies currently in use or in development and observed their principles in relation to recent pathophysiology of post-stroke gait. In both non-disabled and post-stroke subjects, motor control is organized on a task-oriented basis using a common set of a few muscle modules to simultaneously achieve body support, balance control, and forward progression during gait. Hemiparesis following stroke is due to disruption of descending neural pathways, usually with no direct lesion of the brainstem and cerebellar structures involved in motor automatic processes. Post-stroke, improvements of motor activities including standing and locomotion are variable but are typically characterized by a common postural behaviour which involves the unaffected side more for body support and balance control, likely in response to initial muscle weakness of the affected side. Various rehabilitation strategies are regularly used or in development, targeting muscle activity, postural and gait tasks, using more or less high-technology equipment. Reduced walking speed often improves with time and with various rehabilitation strategies, but asymmetric postural behaviour during standing and walking is often reinforced, maintained, or only transitorily decreased. This asymmetric compensatory postural behaviour appears to be robust, driven by support and balance tasks maintaining the predominant use of the unaffected side over the initially impaired affected side. Based on these elements, stroke rehabilitation including affected muscle strengthening and often stretching would first need to correct the postural asymmetric pattern by exploiting postural automatic processes in various particular motor tasks secondarily beneficial to gait. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Electrophysiological effects of Ro 22-9194, a new antiarrhythmic agent, on guinea-pig ventricular cells.

OpenAIRE

Maruyama, K; Kodama, I; Anno, T; Suzuki, R; Toyama, J

1995-01-01

1. Cardiac effects of Ro 22-9194 were examined in papillary muscles and single ventricular myocytes isolated from guinea-pigs and compared with those of moricizine. 2. In papillary muscles, both Ro 22-9194 (> or = 10 microM) and moricizine (> or = 1 microM) caused a significant dose-dependent decrease in the maximum upstroke velocity (Vmax) and a shortening of the action potential duration. 3. In the presence of either drug, trains of stimuli at rates > or = 0.2 Hz led to an exponential decli...

Evaluation of left ventricular function by invasive and noninvasive methods

Energy Technology Data Exchange (ETDEWEB)

Kusukawa, R [Yamaguchi Univ., Ube (Japan). School of Medicine

1982-06-01

Noninvasive methods in cardiology have progressed very rapidly in recent years. Cardiac catheterization and angiocardiography are the standard methods for evaluating of cardiac performance, however, they need expensive apparatus and are time-consuming, arduous procedures which do not permit to repeat frequently, and sometimes risky. In this article, the indices of pump and muscle function of the heart obtained by invasive methods were compared to those indices obtained by noninvasive methods, and correlation between two groups and usefulness and limitation were discussed. Systolic time intervals are convenient and repeatable measures of left ventricular performance in clinical cardiology. There are significant correlations of PEP/LVET with stroke volume, ejection fraction and mean circumferential shortening velocity. Although some limitations are present in application of this method to certain diseases, these measures are useful in the evaluation of left ventricular performance. Echocardiography has made an era of the noninvasive cardiology. Left ventricular volume, ejection fraction, mean circumferential shortening velocity and PSP/ESVI are accurately calculated by echocardiographic measurement. Nuclear cardiology is also accurate noninvasive method in evaluation of cardiac performance. With this tremendous growth in this field, it will make next era of noninvasive cardiology.

Radiological diagnostics of muscle diseases

International Nuclear Information System (INIS)

Weber, M.A.; Essig, M.; Kauczor, H.U.

2007-01-01

Muscular diseases are a heterogeneous group of diseases with difficult differential diagnosis. This article reviews morphological and functional radiological techniques for assessment of muscular diseases. Morphological techniques can describe edema-like changes, lipomatous and atrophic changes of muscular tissue. However, these imaging signs are often not disease-specific. As a result, clinicians assign radiology a secondary role in the management of muscular diseases. Meanwhile, functional radiological techniques allow the assessment of muscle fiber architecture, skeletal muscle perfusion, myocellular sodium-homoeostasis, lipid- and energy-phosphate metabolism, etc. By detecting and spatially localizing pathophysiological phenomena, these new techniques can increase the role of radiology in muscular diseases. (orig.)

Near-infrared spectroscopy for monitoring muscle oxygenation

DEFF Research Database (Denmark)

Boushel, Robert Christopher; Piantadosi, C A

2000-01-01

Near-infrared spectroscopy (NIRS) is a non-invasive method for monitoring oxygen availability and utilization by the tissues. In intact skeletal muscle, NIRS allows semi-quantitative measurements of haemoglobin plus myoglobin oxygenation (tissue O2 stores) and the haemoglobin volume. Specialized...... algorithms allow assessment of the oxidation-reduction (redox) state of the copper moiety (CuA) of mitochondrial cytochrome c oxidase and, with the use of specific tracers, accurate assessment of regional blood flow. NIRS has demonstrated utility for monitoring changes in muscle oxygenation and blood flow...... during submaximal and maximal exercise and under pathophysiological conditions including cardiovascular disease and sepsis. During work, the extent to which skeletal muscles deoxygenate varies according to the type of muscle, type of exercise and blood flow response. In some instances, a strong...

miRNA targeted signaling pathway in the early stage of denervated fast and slow muscle atrophy

Directory of Open Access Journals (Sweden)

Gang Li

2016-01-01

Full Text Available Denervation often results in skeletal muscle atrophy. Different mechanisms seem to be involved in the determination between denervated slow and fast skeletal muscle atrophy. At the epigenetic level, miRNAs are thought to be highly involved in the pathophysiological progress of denervated muscles. We used miRNA microarrays to determine miRNA expression profiles from a typical slow muscle (soleus muscle and a typical fast muscle (tibialis anterior muscle at an early denervation stage in a rat model. Results showed that miR-206, miR-195, miR-23a, and miR-30e might be key factors in the transformation process from slow to fast muscle in denervated slow muscles. Additionally, certain miRNA molecules (miR-214, miR-221, miR-222, miR-152, miR-320, and Let-7e could be key regulatory factors in the denervated atrophy process involved in fast muscle. Analysis of signaling pathway networks revealed the miRNA molecules that were responsible for regulating certain signaling pathways, which were the final targets (e.g., p38 MAPK pathway; Pax3/Pax7 regulates Utrophin and follistatin by HDAC4; IGF1/PI3K/Akt/mTOR pathway regulates atrogin-1 and MuRF1 expression via FoxO phosphorylation. Our results provide a better understanding of the mechanisms of denervated skeletal muscle pathophysiology.

GLUT11, but not GLUT8 or GLUT12, is expressed in human skeletal muscle in a fibre type-specific pattern

DEFF Research Database (Denmark)

Gaster, M; Handberg, A; Schürmann, A

2004-01-01

or amyotrophic lateral sclerosis (ALS) were studied. GLUT8 and 12 immunoreactivity was below detection level in both developing and adult muscle fibres. GLUT11 immunoreactivity, however, was present in slow-twitch muscle fibres, but not in fast twitch fibres. Since, in contrast, GLUT4 was expressed in all...... exclusively in slow-twitch muscle fibres and is unaffected by physiological and pathophysiological conditions except in primary myopathy. GLUT8 and GLUT12 do not appear to be of importance in human muscle under physiological and pathophysiological conditions....... to induce GLUT8 or -12 expression. Likewise, the fibre type-dependent pattern of GLUT11 immunoreactivity was unaltered. However, some slow muscle fibres lose their GLUT11 immunoreactivity under regeneration. Our results indicate that GLUT11 immunoreactivity, in contrast to that of GLUT4, is expressed...

Systolic left ventricular function according to left ventricular concentricity and dilatation in hypertensive patients

DEFF Research Database (Denmark)

Bang, Casper; Gerdts, Eva; Aurigemma, Gerard P

2013-01-01

Left ventricular hypertrophy [LVH, high left ventricular mass (LVM)] is traditionally classified as concentric or eccentric based on left ventricular relative wall thickness. We evaluated left ventricular systolic function in a new four-group LVH classification based on left ventricular dilatation...... [high left ventricular end-diastolic volume (EDV) index and concentricity (LVM/EDV)] in hypertensive patients....

Left ventricular function in patients with ventricular arrhythmias and aortic valve disease

International Nuclear Information System (INIS)

Santinga, J.T.; Kirsh, M.M.; Brady, T.J.; Thrall, J.; Pitt, B.

1983-01-01

Forty patients having aortic valve replacement were evaluated preoperatively for ventricular arrhythmia and left ventricular ejection fraction. Arrhythmias were classified as complex or simple using the Lown criteria on the 24-hour ambulatory electrocardiogram; ejection fractions were determined by radionuclide gated blood pool analysis and contrast angiography. The ejection fractions determined by radionuclide angiography were 59.1 +/- 13.1% for 26 patients with simple or no ventricular arrhythmias, and 43.9 +/- 20.3% for 14 patients with complex ventricular arrhythmias (p less than 0.01). Ejection fractions determined by angiography, available for 31 patients, were also lower in patients with complex ventricular arrhythmias (61.1 +/- 16.3% versus 51.4 +/- 13.4%; p less than 0.05). Seven of 9 patients showing conduction abnormalities on the electrocardiogram had complex ventricular arrhythmias. Eight of 20 patients with aortic stenosis had complex ventricular arrhythmias, while 2 of 13 patients with aortic insufficiency had such arrhythmias. It is concluded that decreased left ventricular ejection fraction, intraventricular conduction abnormalities, and aortic stenosis are associated with an increased frequency of complex ventricular arrhythmias in patients with aortic valve disease

Rest and exercise ventricular function in adults with congenital ventricular septal defects

International Nuclear Information System (INIS)

Jablonsky, G.; Hilton, J.D.; Liu, P.P.; Morch, J.E.; Druck, M.N.; Bar-Shlomo, B.Z.; McLaughlin, P.R.

1983-01-01

Rest and exercise right and left ventricular function were compared using equilibrium gated radionuclide angiography in 19 normal sedentary control subjects and 34 patients with hemodynamically documented congenital ventricular septal defect (VSD). Gated radionuclide angiography was performed at rest and during each level of graded supine bicycle exercise to fatigue. Heart rate, blood pressure, maximal work load achieved, and right and left ventricular ejection fractions were assessed. The control subjects demonstrated an increase in both the left and right ventricular ejection fractions with exercise. All study groups failed to demonstrate an increase in ejection fraction in either ventricle with exercise. Furthermore, resting left ventricular ejection fraction in Groups 2 and 3 was lower than that in the control subjects and resting right ventricular ejection fraction was lower in Group 3 versus control subjects. Thus left and right ventricular function on exercise were abnormal in patients with residual VSD as compared with control subjects; rest and exercise left ventricular ejection fractions remained abnormal despite surgical closure of VSD in the remote past; resting left and right ventricular function was abnormal in patients with Eisenmenger's complex; lifelong volume overload may be detrimental to myocardial function

A primary reduced TCA flux governs substrate oxidation in T2D skeletal muscle

DEFF Research Database (Denmark)

Gaster, Michael

2012-01-01

Our current knowledge on substrate oxidation in skeletal muscle in relation to insulin resistance and type 2 diabetes (T2D) originate mainly from in vivo studies. The oxidative capacity of skeletal muscle is highly influenced by physical activity, ageing, hormonal status, and fiber type composition...... further regulatory mechanism to our understanding of substrate oxidation in human skeletal muscle during normo- an pathophysiological conditions, focusing especially on the governing influence of a primary reduced TCA flux for the diabetic phenotype in skeletal muscle....

Arrhythmogenic Right Ventricular Cardiomyopathy in an Endurance Athlete Presenting with Ventricular Tachycardia and Normal Right Ventricular Function.

Science.gov (United States)

Hedley, Jeffrey S; Al Mheid, Ibhar; Alikhani, Zoubin; Pernetz, Maria A; Kim, Jonathan H

2017-08-01

Arrhythmogenic right ventricular cardiomyopathy, a genetically inherited disease that results in fibrofatty replacement of normal cardiac myocytes, has been associated with sudden cardiac death in athletes. Long-term participation in endurance exercise hastens the development of both the arrhythmic and structural arrhythmogenic right ventricular cardiomyopathy phenotypes. We describe the unusual case of a 34-year-old, symptomatic, female endurance athlete who had arrhythmogenic right ventricular cardiomyopathy in the presence of a structurally normal right ventricle. Clinicians should be aware of this infrequent presentation when evaluating athletic patients who have ventricular arrhythmias and normal findings on cardiac imaging studies.

Prophylactic implantable defibrillator in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia and no prior ventricular fibrillation or sustained ventricular tachycardia.

LENUS (Irish Health Repository)

Corrado, Domenico

2010-09-21

The role of implantable cardioverter-defibrillator (ICD) in patients with arrhythmogenic right ventricular cardiomyopathy\\/dysplasia and no prior ventricular fibrillation (VF) or sustained ventricular tachycardia is an unsolved issue.

Non-alcoholic fatty liver disease is associated with left ventricular diastolic dysfunction in essential hypertension.

Science.gov (United States)

Fallo, F; Dalla Pozza, A; Sonino, N; Lupia, M; Tona, F; Federspil, G; Ermani, M; Catena, C; Soardo, G; Di Piazza, L; Bernardi, S; Bertolotto, M; Pinamonti, B; Fabris, B; Sechi, L A

2009-11-01

Insulin resistance is recognized as the pathophysiological hallmark of non-alcoholic fatty liver disease (NAFLD). A relation between insulin sensitivity and left ventricular morphology and function has been reported in essential hypertension, where a high prevalence of NAFLD has been recently found. We investigated the inter-relationship between left ventricular morphology/function, metabolic parameters and NAFLD in 86 never-treated essential hypertensive patients subdivided in two subgroups according to the presence (n = 48) or absence (n = 38) of NAFLD at ultrasonography. The two groups were similar as to sex, age and blood pressure levels. No patient had diabetes mellitus, obesity, hyperlipidemia, or other risk factors for liver disease. Body mass index, waist circumference, triglycerides, glucose, insulin, homeostasis model of assessment index for insulin resistance (HOMA-IR), aspartate aminotransferase and alanine aminotransferase were higher and adiponectin levels were lower in patients with NAFLD than in patients without NAFLD, and were associated with NAFLD at univariate analysis. Patients with NAFLD had similar prevalence of left ventricular hypertrophy compared to patients without NAFLD, but a higher prevalence of diastolic dysfunction (62.5 vs 21.1%, P 220 ms. Diastolic dysfunction (P = 0.040) and HOMA-IR (P = 0.012) remained independently associated with NAFLD at backward multivariate analysis. Non-alcoholic fatty liver disease was associated with insulin resistance and abnormalities of left ventricular diastolic function in a cohort of patients with essential hypertension, suggesting a concomitant increase of metabolic and cardiac risk in this condition.

Recruitment pattern of sympathetic muscle neurons during premature ventricular contractions in heart failure patients and controls.

Science.gov (United States)

Maslov, Petra Zubin; Breskovic, Toni; Brewer, Danielle N; Shoemaker, J Kevin; Dujic, Zeljko

2012-12-01

Premature ventricular contractions (PVC) elicit larger bursts of multiunit muscle sympathetic nerve activity (MSNA), reflecting the ability to increase postganglionic axonal recruitment. We tested the hypothesis that chronic heart failure (CHF) limits the ability to recruit postganglionic sympathetic neurons as a response to PVC due to the excessive sympathetic activation in these patients. Sympathetic neurograms of sufficient signal-to-noise ratio were obtained from six CHF patients and from six similarly aged control individuals. Action potentials (APs) were extracted from the multiunit sympathetic neurograms during sinus rhythm bursts and during the post-PVC bursts. These APs were classified on the basis of the frequency per second, the content per burst, and the peak-to-peak amplitude, which formed the basis of binning the APs into active clusters. Compared with controls, CHF had higher APs per burst and higher number of active clusters per sinus rhythm burst (P < 0.05). Compared with sinus rhythm bursts, both groups increased AP frequency and the number of active clusters in the post-PVC burst (P < 0.05). However, compared with controls, the increase in burst integral, AP frequency, and APs per burst during the post-PVC burst was less in CHF patients. Nonetheless, the PVC-induced increase in active clusters per burst was similar between the groups. Thus, these CHF patients retained the ability to recruit larger APs but had a diminished ability to increase overall AP content.

A 13 year old girl with muscle weakness and ventricular tachycardia

International Nuclear Information System (INIS)

Rauf, M.; Zeb, S.; Adil, M.; Gul, A.M.; Hafizullah, M.

2012-01-01

Gitelman's syndrome is characterized by hypokalemia, hypomagnesemia and hypocalciuria. It is an autosomal recessive renal disorder and mostly present with asymptomatic hypokalemia but muscle cramps, dizziness, fatigue, muscle weakness and arrhythmias are the usual presentation. Same is the case with us, young girl presented with multiple symptoms and arrhythmia was worked up for electrolyte imbalance. Long term prognosis in terms of maintaining growth, renal function and life expectancy is excellent. Family screening is important for its early detection and treatment. This needs future genetic studies. (author)

Basal cardiomyopathy develops in rabbits with ventricular tachyarrhythmias induced by a single injection of adrenaline.

Science.gov (United States)

Ashida, Terunao; Takato, Tetsuya; Matsuzaki, Gen; Seko, Yoshinori; Fujii, Jun; Kawai, Sachio

2014-01-01

We have recently demonstrated that basal cardiomyopathy develops in rabbits with ventricular tachyarrhythmias that have been induced by electrical stimulation of the cervical vagus. This study investigated whether similar basal cardiomyopathy would develop in rabbits with ventricular tachyarrhythmias induced by a single injection of adrenaline. Adrenaline was intravenously infused for 10-360 seconds in anesthetized rabbits. Colloidal carbon was injected after adrenaline infusion. Wall movement velocity of the left ventricular base was assessed by tissue Doppler echocardiography. Animals were killed either 1 week or 3-4 weeks later. Pathological lesions were identified by deposits of carbon particles. Animals were divided into two groups according to the infused dose of adrenaline. The small-dose group (group S, n = 15) received 1-10 μg and the large-dose group (group L, n = 23) received 15-60 μg of adrenaline. Adrenaline infusion induced premature ventricular contractions followed by monomorphic ventricular tachycardias in 22 of 23 animals in group L, but in only 1 of 15 animals in group S. Wall movement velocity of the left ventricular base decreased just after adrenaline infusion, remained low after 1 week, and recovered to near-baseline levels after 3-4 weeks in group L. Unique cardiac lesions identified by deposits of carbon particles were frequently observed on the left ventricular basal portion, almost always associated with the mitral valve and papillary muscles, but were never observed in the apical area. Lesions involving all areas of the left ventricular basal portion were observed in 22 of 23 animals in group L, but in only 2 of 15 animals in group S. Basal cardiomyopathy developed in rabbits with ventricular tachycardias induced by a single injection of adrenaline.

Platelet-Derived Growth Factor BB Influences Muscle Regeneration in Duchenne Muscle Dystrophy.

Science.gov (United States)

Piñol-Jurado, Patricia; Gallardo, Eduard; de Luna, Noemi; Suárez-Calvet, Xavier; Sánchez-Riera, Carles; Fernández-Simón, Esther; Gomis, Clara; Illa, Isabel; Díaz-Manera, Jordi

2017-08-01

Duchenne muscular dystrophy (DMD) is characterized by a progressive loss of muscle fibers, and their substitution by fibrotic and adipose tissue. Many factors contribute to this process, but the molecular pathways related to regeneration and degeneration of muscle are not completely known. Platelet-derived growth factor (PDGF)-BB belongs to a family of growth factors that regulate proliferation, migration, and differentiation of mesenchymal cells. The role of PDGF-BB in muscle regeneration in humans has not been studied. We analyzed the expression of PDGF-BB in muscle biopsy samples from controls and patients with DMD. We performed in vitro experiments to understand the effects of PDGF-BB on myoblasts involved in the pathophysiology of muscular dystrophies and confirmed our results in vivo by treating the mdx murine model of DMD with repeated i.m. injections of PDGF-BB. We observed that regenerating and necrotic muscle fibers in muscle biopsy samples from DMD patients expressed PDGF-BB. In vitro, PDGF-BB attracted myoblasts and activated their proliferation. Analysis of muscles from the animals treated with PDGF-BB showed an increased population of satellite cells and an increase in the number of regenerative fibers, with a reduction in inflammatory infiltrates, compared with those in vehicle-treated mice. Based on our results, PDGF-BB may play a protective role in muscular dystrophies by enhancing muscle regeneration through activation of satellite cell proliferation and migration. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Statin-associated muscle symptoms: impact on statin therapy

DEFF Research Database (Denmark)

Stroes, Erik S; Thompson, Paul D; Corsini, Alberto

2015-01-01

degradation, thereby providing a potential link between statins and muscle symptoms; controlled mechanistic and genetic studies in humans are necessary to further understanding. The Panel proposes to identify SAMS by symptoms typical of statin myalgia (i.e. muscle pain or aching) and their temporal......Statin-associated muscle symptoms (SAMS) are one of the principal reasons for statin non-adherence and/or discontinuation, contributing to adverse cardiovascular outcomes. This European Atherosclerosis Society (EAS) Consensus Panel overviews current understanding of the pathophysiology of statin......-associated myopathy, and provides guidance for diagnosis and management of SAMS. Statin-associated myopathy, with significant elevation of serum creatine kinase (CK), is a rare but serious side effect of statins, affecting 1 per 1000 to 1 per 10 000 people on standard statin doses. Statin-associated muscle symptoms...

Genetic bases of arrhythmogenic right ventricular cardiomyopathy

Directory of Open Access Journals (Sweden)

Alessandra Rampazzo

2010-05-01

Full Text Available Arrhythmogenic right ventricular cardiomyopathy (ARVC is a heart muscle disease in which the pathological substrate is a fibro-fatty replacement of the right ventricular myocardium. The major clinical features are different types of arrhythmias with a left branch block pattern. ARVC shows autosomal dominant inheritance with incomplete penetrance. Recessive forms were also described, although in association with skin disorders. Ten genetic loci have been discovered so far and mutations were reported in five different genes. ARVD1 was associated with regulatory mutations of transforming growth factor beta-3 (TGFβ3, whereas ARVD2, characterized by effort-induced polymorphic arrhythmias, was associated with mutations in cardiac ryanodine receptor-2 (RYR2. All other mutations identified to date have been detected in genes encoding desmosomal proteins: plakoglobin (JUP which causes Naxos disease (a recessive form of ARVC associated with palmoplantar keratosis and woolly hair; desmoplakin (DSP which causes the autosomal dominant ARVD8 and plakophilin-2 (PKP2 involved in ARVD9. Desmosomes are important cell-to-cell adhesion junctions predominantly found in epidermis and heart; they are believed to couple cytoskeletal elements to plasma membrane in cell-to-cell or cell-to-substrate adhesions.

Is the epicardial left ventricular lead implantation an alternative approach to percutaneous attempt in patients with Steinert disease? A case report

Science.gov (United States)

PAPA, ANDREA ANTONIO; RAGO, ANNA; PETILLO, ROBERTA; D’AMBROSIO, PAOLA; SCUTIFERO, MARIANNA; FEO, MARISA DE; MAIELLO, CIRO; PALLADINO, ALBERTO

2017-01-01

Steinert’s disease or Myotonic Dystrophy type 1 (DM1) is an autosomal dominant multisystemic disorder characterized by myotonia, muscle and facial weakness, cataracts, cognitive, endocrine and gastrointestinal involvement, and cardiac conduction abnormalities. Although mild myocardial dysfunction may be detected in this syndrome with age, overt myocardial dysfunction with heart failure is not frequent. Cardiac resynchronization therapy is an effective treatment to improve morbidity and reduce mortality in patients with DM1 showing intra-ventricular conduction delay and/or congestive heart failure. We report the case of a patient with Steinert disease showing an early onset ventricular dysfunction due to chronic right ventricular apical pacing, in which an epicardial left ventricular lead implantation was performed following the failure of the percutaneous attempt. As no relief in symptoms of heart failure, nor an improvement of left ventricular ejection fraction and reverse remodelling was observed six months later, the patient was addressed to the heart transplantation.

The role of the IGF-1 Ec in myoskeletal system and osteosarcoma pathophysiology.

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Armakolas, Nikolaos; Armakolas, Athanasios; Antonopoulos, Athanasios; Dimakakos, Andreas; Stathaki, Martha; Koutsilieris, Michael

2016-12-01

Growth hormone (GH) regulated mainly liver-produced insulin-like growth factor 1 (IGF-1) is a key molecule in embryonic & post embryonic development that is also involved in cancer biology. Herein we review new insights of the role of igf-1 gene products and of the IGF-1Ec isoform in muscle and bone development/repair and its role in osteosarcoma pathophysiology, underlying the possible role of the Ec peptide as a future therapeutic target. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Altered pharyngeal muscles in Parkinson disease.

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Mu, Liancai; Sobotka, Stanislaw; Chen, Jingming; Su, Hungxi; Sanders, Ira; Adler, Charles H; Shill, Holly A; Caviness, John N; Samanta, Johan E; Beach, Thomas G

2012-06-01

Dysphagia (impaired swallowing) is common in patients with Parkinson disease (PD) and is related to aspiration pneumonia, the primary cause of death in PD. Therapies that ameliorate the limb motor symptoms of PD are ineffective for dysphagia. This suggests that the pathophysiology of PD dysphagia may differ from that affecting limb muscles, but little is known about potential neuromuscular abnormalities in the swallowing muscles in PD. This study examined the fiber histochemistry of pharyngeal constrictor and cricopharyngeal sphincter muscles in postmortem specimens from 8 subjects with PD and 4 age-matched control subjects. Pharyngeal muscles in subjects with PD exhibited many atrophic fibers, fiber type grouping, and fast-to-slow myosin heavy chain transformation. These alterations indicate that the pharyngeal muscles experienced neural degeneration and regeneration over the course of PD. Notably, subjects with PD with dysphagia had a higher percentage of atrophic myofibers versus with those without dysphagia and controls. The fast-to-slow fiber-type transition is consistent with abnormalities in swallowing, slow movement of food, and increased tone in the cricopharyngeal sphincter in subjects with PD. The alterations in the pharyngeal muscles may play a pathogenic role in the development of dysphagia in subjects with PD.

Stress induced right ventricular dysfunction: An indication of reversible right ventricular ischaemia

International Nuclear Information System (INIS)

Underwood, S.R.; Walton, S.; Emanuel, R.W.; Swanton, R.H.; Campos Costa, D.; Laming, P.J.; Ell, P.J.

1987-01-01

Stress induced changes in left ventricular ejection fraction are widely used in the detection and assessment of coronary artery disease. This study demonstrates that right ventricular dysfunction may also occur, and assesses its significance in terms of coronary artery anatomy. This study involved 14 normal subjects and 26 with coronary artery disease investigated by equilibrium radionuclide ventriculography, at rest and during maximal dynamic exercise. Mean normal resting right ventricular ejection fraction (RVEF) was 0.40 (SD 0.118), and all normal subjects increased RVEF with stress (mean ΔRVEF+0.13 SD 0.099). Mean ΔRVEF in the subjects with coronary artery disease was significantly lower at 0.00 (SD 0.080), but there was overlap between the two groups. The largest falls in RVEF were seen if the right coronary artery was occluded without retrograde filling. In this subgroup with the most severely compromised right ventricular perfusion (nine subjects), RVEF always fell with stress, and mean ΔRVEF was -0.08 (SD 0.050). There was no significant correlation between ΔLVEF and ΔRVEF, implying that the right ventricular dysfunction was due to right ventricular ischaemia, rather than secondary to left ventricular dysfunction. Stress induced right ventricular ischaemia can therefore be detected readily by radionuclide ventriculography. (orig.)

Influence of slice thickness on the determination of left ventricular wall thickness and dimension by magnetic resonance imaging

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Ohnishi, Shusaku; Fukui, Sugao; Atsumi, Chisato and others

1989-02-01

Wall thickness of the ventricular septum and left ventricle, and left ventricular cavity dimension were determined on magnetic resonance (MR) images with slices 5 mm and 10 mm in thickness. Subjects were 3 healthy volunteers and 7 patients with hypertension (4), hypertrophic cardiomyopathy (one) or valvular heart disease (2). In visualizing the cardiac structures such as left ventricular papillary muscle and right and left ventricles, 5 mm-thick images were better than 10 mm-thick images. Edges of ventricular septum and left ventricular wall were more clearly visualized on 5 mm-thick images than 10 mm-thick images. Two mm-thick MR images obtained from 2 patients yielded the most excellent visualization in end-systole, but failed to reveal cardiac structures in detail in end-diastole. Phantom studies revealed no significant differences in image quality of 10 mm and 5 mm in thickness in the axial view 80 degree to the long axis. In the axial view 45 degree to the long axis, 10 mm-thick images were inferior to 5 mm-thick images in detecting the edge of the septum and the left ventricular wall. These results indicate that the selection of slice thickness is one of the most important determinant factors in the measurement of left ventricular wall thickness and cavity dimension. (Namekawa, K).

Influence of slice thickness on the determination of left ventricular wall thickness and dimension by magnetic resonance imaging

International Nuclear Information System (INIS)

Ohnishi, Shusaku; Fukui, Sugao; Atsumi, Chisato

1989-01-01

Wall thickness of the ventricular septum and left ventricle, and left ventricular cavity dimension were determined on magnetic resonance (MR) images with slices 5 mm and 10 mm in thickness. Subjects were 3 healthy volunteers and 7 patients with hypertension (4), hypertrophic cardiomyopathy (one) or valvular heart disease (2). In visualizing the cardiac structures such as left ventricular papillary muscle and right and left ventricles, 5 mm-thick images were better than 10 mm-thick images. Edges of ventricular septum and left ventricular wall were more clearly visualized on 5 mm-thick images than 10 mm-thick images. Two mm-thick MR images obtained from 2 patients yielded the most excellent visualization in end-systole, but failed to reveal cardiac structures in detail in end-diastole. Phantom studies revealed no significant differences in image quality of 10 mm and 5 mm in thickness in the axial view 80 degree to the long axis. In the axial view 45 degree to the long axis, 10 mm-thick images were inferior to 5 mm-thick images in detecting the edge of the septum and the left ventricular wall. These results indicate that the selection of slice thickness is one of the most important determinant factors in the measurement of left ventricular wall thickness and cavity dimension. (Namekawa, K)

Remote Zone Extracellular Volume and Left Ventricular Remodeling in Survivors of ST-Elevation Myocardial Infarction

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Carberry, Jaclyn; Carrick, David; Haig, Caroline; Rauhalammi, Samuli M.; Ahmed, Nadeem; Mordi, Ify; McEntegart, Margaret; Petrie, Mark C.; Eteiba, Hany; Hood, Stuart; Watkins, Stuart; Lindsay, Mitchell; Davie, Andrew; Mahrous, Ahmed; Ford, Ian; Sattar, Naveed; Welsh, Paul; Radjenovic, Aleksandra; Oldroyd, Keith G.

2016-01-01

The natural history and pathophysiological significance of tissue remodeling in the myocardial remote zone after acute ST-elevation myocardial infarction (STEMI) is incompletely understood. Extracellular volume (ECV) in myocardial regions of interest can now be measured with cardiac magnetic resonance imaging. Patients who sustained an acute STEMI were enrolled in a cohort study (BHF MR-MI [British Heart Foundation Magnetic Resonance Imaging in Acute ST-Segment Elevation Myocardial Infarction study]). Cardiac magnetic resonance was performed at 1.5 Tesla at 2 days and 6 months post STEMI. T1 modified Look-Locker inversion recovery mapping was performed before and 15 minutes after contrast (0.15 mmol/kg gadoterate meglumine) in 140 patients at 2 days post STEMI (mean age: 59 years, 76% male) and in 131 patients at 6 months post STEMI. Remote zone ECV was lower than infarct zone ECV (25.6±2.8% versus 51.4±8.9%; Premote zone ECV (Premote zone ECV (P=0.010). No ST-segment resolution (P=0.034) and extent of ischemic area at risk (Premote zone ECV at 6 months (ΔECV). ΔECV was a multivariable associate of the change in left ventricular end-diastolic volume at 6 months (regression coefficient [95% confidence interval]: 1.43 (0.10–2.76); P=0.036). ΔECV is implicated in the pathophysiology of left ventricular remodeling post STEMI, but because the effect size is small, ΔECV has limited use as a clinical biomarker of remodeling. Clinical Trial Registration— URL: https://www.clinicaltrials.gov. Unique identifier: NCT02072850. PMID:27354423

Rat rotator cuff muscle responds differently from hindlimb muscle to a combined tendon-nerve injury.

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Davies, Michael R; Ravishankar, Bharat; Laron, Dominique; Kim, Hubert T; Liu, Xuhui; Feeley, Brian T

2015-07-01

Rotator cuff tears (RCTs) are among the most common musculoskeletal injuries seen by orthopaedic surgeons. Clinically, massive cuff tears lead to unique pathophysiological changes in rotator cuff muscle, including atrophy, and massive fatty infiltration, which are rarely seen in other skeletal muscles. Studies in a rodent model for RCT have demonstrated that these histologic findings are accompanied by activation of the Akt/mammalian target of rapamycin (mTOR) and transforming growth factor-β (TGF-β) pathways following combined tendon-nerve injury. The purpose of this study was to compare the histologic and molecular features of rotator cuff muscle and gastrocnemius muscle--a major hindlimb muscle, following combined tendon-nerve injury. Six weeks after injury, the rat gastrocnemius did not exhibit notable fatty infiltration compared to the rotator cuff. Likewise, the adipogenic markers SREBP-1 and PPARγ as well as the TGF-β canonical pathway were upregulated in the rotator cuff, but not the gastrocnemius. Our study suggests that the rat rotator cuff and hindlimb muscles differ significantly in their response to a combined tendon-nerve injury. Clinically, these findings highlight the unique response of the rotator cuff to injury, and may begin to explain the poor outcomes of massive RCTs compared to other muscle-tendon injuries. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Hemorrhagic Cardioembolic Stroke Secondary to a Left Ventricular Thrombus: a Therapeutic Dilemma

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Khalil Al-Farsi

2013-01-01

Full Text Available Cardiogenic embolism is a major cause of stroke and often leads to significant morbidity and mortality. Despite the recent advances in our understanding of the pathophysiology of stroke and its risk factors, diagnosis and therapy; some case scenarios still present a real challenge for the treating physicians. We report a case of a 50 year old male patient presenting with multi-territory cerebral infarctions due to a left ventricular mobile thrombus complicated with hemorrhagic transformation at the time of presentation. Gradual introduction of anticoagulation coupled with a multidisciplinary team approach advocating careful daily clinical assessment of the patient and regular echocardiographic and neuroimaging studies have resulted in a better management and achievement of therapeutic goals.

Systolic ventricular filling.

Science.gov (United States)

Torrent-Guasp, Francisco; Kocica, Mladen J; Corno, Antonio; Komeda, Masashi; Cox, James; Flotats, A; Ballester-Rodes, Manel; Carreras-Costa, Francesc

2004-03-01

The evidence of the ventricular myocardial band (VMB) has revealed unavoidable coherence and mutual coupling of form and function in the ventricular myocardium, making it possible to understand the principles governing electrical, mechanical and energetical events within the human heart. From the earliest Erasistratus' observations, principal mechanisms responsible for the ventricular filling have still remained obscured. Contemporary experimental and clinical investigations unequivocally support the attitude that only powerful suction force, developed by the normal ventricles, would be able to produce an efficient filling of the ventricular cavities. The true origin and the precise time frame for generating such force are still controversial. Elastic recoil and muscular contraction were the most commonly mentioned, but yet, still not clearly explained mechanisms involved in the ventricular suction. Classical concepts about timing of successive mechanical events during the cardiac cycle, also do not offer understandable insight into the mechanism of the ventricular filling. The net result is the current state of insufficient knowledge of systolic and particularly diastolic function of normal and diseased heart. Here we summarize experimental evidence and theoretical backgrounds, which could be useful in understanding the phenomenon of the ventricular filling. Anatomy of the VMB, and recent proofs for its segmental electrical and mechanical activation, undoubtedly indicates that ventricular filling is the consequence of an active muscular contraction. Contraction of the ascendent segment of the VMB, with simultaneous shortening and rectifying of its fibers, produces the paradoxical increase of the ventricular volume and lengthening of its long axis. Specific spatial arrangement of the ascendent segment fibers, their interaction with adjacent descendent segment fibers, elastic elements and intra-cavitary blood volume (hemoskeleton), explain the physical principles

Possible involvement of mitochondrial energy-producing ability in the development of right ventricular failure in monocrotaline-induced pulmonary hypertensive rats.

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Daicho, Takuya; Yagi, Tatsuya; Abe, Yohei; Ohara, Meiko; Marunouchi, Tetsuro; Takeo, Satoshi; Tanonaka, Kouichi

2009-09-01

The present study was undertaken to explore the possible involvement of alterations in the mitochondrial energy-producing ability in the development of the right ventricular failure in monocrotaline-administered rats. The rats at the 6th week after subcutaneous injection of 60 mg/kg monocrotaline revealed marked myocardial hypertrophy and fibrosis, that is, severe cardiac remodeling. The time-course study on the cardiac hemodynamics of the monocrotaline-administered rat by the cannula and echocardiographic methods showed a reduction in cardiac double product, a decrease in cardiac output index, and an increase in the right ventricular Tei index, suggesting that the right ventricular failure was induced at the 6th week after monocrotaline administration in rats. The mitochondrial oxygen consumption rate of the right ventricular muscle isolated from the monocrotaline-administered animal was decreased, which was associated with a reduction in myocardial high-energy phosphates. Furthermore, the decrease in mitochondrial oxygen consumption rate was inversely related to the increase in the right ventricular Tei index of the monocrotaline-administered rats. These results suggest that impairment of the mitochondrial energy-producing ability is involved in the development of the right ventricular failure in monocrotaline-induced pulmonary hypertensive rats.

Smooth muscle myosin light chain kinase efficiently phosphorylates serine 15 of cardiac myosin regulatory light chain

International Nuclear Information System (INIS)

Josephson, Matthew P.; Sikkink, Laura A.; Penheiter, Alan R.; Burghardt, Thomas P.; Ajtai, Katalin

2011-01-01

Highlights: ► Cardiac myosin regulatory light chain (MYL2) is phosphorylated at S15. ► Smooth muscle myosin light chain kinase (smMLCK) is a ubiquitous kinase. ► It is a widely believed that MYL2 is a poor substrate for smMLCK. ► In fact, smMLCK efficiently and rapidly phosphorylates S15 in MYL2. ► Phosphorylation kinetics measured by novel fluorescence method without radioactivity. -- Abstract: Specific phosphorylation of the human ventricular cardiac myosin regulatory light chain (MYL2) modifies the protein at S15. This modification affects MYL2 secondary structure and modulates the Ca 2+ sensitivity of contraction in cardiac tissue. Smooth muscle myosin light chain kinase (smMLCK) is a ubiquitous kinase prevalent in uterus and present in other contracting tissues including cardiac muscle. The recombinant 130 kDa (short) smMLCK phosphorylated S15 in MYL2 in vitro. Specific modification of S15 was verified using the direct detection of the phospho group on S15 with mass spectrometry. SmMLCK also specifically phosphorylated myosin regulatory light chain S15 in porcine ventricular myosin and chicken gizzard smooth muscle myosin (S20 in smooth muscle) but failed to phosphorylate the myosin regulatory light chain in rabbit skeletal myosin. Phosphorylation kinetics, measured using a novel fluorescence method eliminating the use of radioactive isotopes, indicates similar Michaelis–Menten V max and K M for regulatory light chain S15 phosphorylation rates in MYL2, porcine ventricular myosin, and chicken gizzard myosin. These data demonstrate that smMLCK is a specific and efficient kinase for the in vitro phosphorylation of MYL2, cardiac, and smooth muscle myosin. Whether smMLCK plays a role in cardiac muscle regulation or response to a disease causing stimulus is unclear but it should be considered a potentially significant kinase in cardiac tissue on the basis of its specificity, kinetics, and tissue expression.

Smooth muscle myosin light chain kinase efficiently phosphorylates serine 15 of cardiac myosin regulatory light chain

Energy Technology Data Exchange (ETDEWEB)

Josephson, Matthew P.; Sikkink, Laura A. [Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905 (United States); Penheiter, Alan R. [Molecular Medicine Program, Mayo Clinic, Rochester, MN 55905 (United States); Burghardt, Thomas P., E-mail: burghardt@mayo.edu [Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905 (United States); Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN 55905 (United States); Ajtai, Katalin [Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905 (United States)

2011-12-16

Highlights: Black-Right-Pointing-Pointer Cardiac myosin regulatory light chain (MYL2) is phosphorylated at S15. Black-Right-Pointing-Pointer Smooth muscle myosin light chain kinase (smMLCK) is a ubiquitous kinase. Black-Right-Pointing-Pointer It is a widely believed that MYL2 is a poor substrate for smMLCK. Black-Right-Pointing-Pointer In fact, smMLCK efficiently and rapidly phosphorylates S15 in MYL2. Black-Right-Pointing-Pointer Phosphorylation kinetics measured by novel fluorescence method without radioactivity. -- Abstract: Specific phosphorylation of the human ventricular cardiac myosin regulatory light chain (MYL2) modifies the protein at S15. This modification affects MYL2 secondary structure and modulates the Ca{sup 2+} sensitivity of contraction in cardiac tissue. Smooth muscle myosin light chain kinase (smMLCK) is a ubiquitous kinase prevalent in uterus and present in other contracting tissues including cardiac muscle. The recombinant 130 kDa (short) smMLCK phosphorylated S15 in MYL2 in vitro. Specific modification of S15 was verified using the direct detection of the phospho group on S15 with mass spectrometry. SmMLCK also specifically phosphorylated myosin regulatory light chain S15 in porcine ventricular myosin and chicken gizzard smooth muscle myosin (S20 in smooth muscle) but failed to phosphorylate the myosin regulatory light chain in rabbit skeletal myosin. Phosphorylation kinetics, measured using a novel fluorescence method eliminating the use of radioactive isotopes, indicates similar Michaelis-Menten V{sub max} and K{sub M} for regulatory light chain S15 phosphorylation rates in MYL2, porcine ventricular myosin, and chicken gizzard myosin. These data demonstrate that smMLCK is a specific and efficient kinase for the in vitro phosphorylation of MYL2, cardiac, and smooth muscle myosin. Whether smMLCK plays a role in cardiac muscle regulation or response to a disease causing stimulus is unclear but it should be considered a potentially significant

Serum levels of advanced glycation end products are associated with left ventricular diastolic function in patients with type 1 diabetes

DEFF Research Database (Denmark)

Berg, T J; Snorgaard, O; Faber, J

1999-01-01

Impairment of left ventricular diastolic function, possibly caused by increased collagen cross-linking of the cardiac muscle, is common in patients with type 1 diabetes even without coronary artery disease. Advanced glycation end products (AGEs) cross-link tissue collagen and are found within...

Auricular tachycardia: therapeutic and pathophysiologic news concepts: literature review and casuistic Service presentation

International Nuclear Information System (INIS)

Horta, J. de; Reyes, W.; Calleriza, F.; Pouso, J.; Besada, E.

1998-01-01

The auricular tachycardia are the supraventricular tachycardias whose origin mechanism and maintenance is located at level exclusively auricular. It show diagnostic and therapeutics difficulties.The inadequate handling can cause commitment of the ventricular function and to commit the predict vital.The pharmacological treatment, is more used is few effective.The ablation for catheter with radiofrequency is a new weapon transcendent therapy for the resolution of a significant group of these patients. A review of the concept of auricular tachycardias, it upgrades its classification and the mechanisms pathophysiologic.It describes the techniques of ablation for catheter in these arrhythmias and their results are revised in the literature. In the end it presents the casuistry of the Service in the treatment of the auricular tachycardias focal s,incision ales and atrial flutter by means of ablation for catheter with radiofrequency [es

Differential effects of thioridazine enantiomers on action potential duration in rabbit papillary muscle

DEFF Research Database (Denmark)

Jensen, Ask Schou; Pennisi, Cristian Pablo; Sevcencu, Cristian

2015-01-01

with (+)-thioridazine. In this study we for the first time investigate the cardiotoxicity of the isolated thioridazine enantiomers and show their effects on ventricular repolarization. The effects of (+)-thioridazine, (-)-thioridazine, and racemate on the rabbit ventricular action potential duration (APD) were...... investigated in a randomized controlled blinded experiment. Action potentials were measured in papillary muscles isolated from 21 female rabbits, and the drug effect on 90% APD in comparison with control (DeltaDelta-APD90) was evaluated. Increasing concentrations of (+)-thioridazine and the racemate caused...

Effect of voluntary physical activity initiated at age 7 months on skeletal hindlimb and cardiac muscle function in mdx mice of both genders.

Science.gov (United States)

Ferry, Arnaud; Benchaouir, Rachid; Joanne, Pierre; Peat, Rachel A; Mougenot, Nathalie; Agbulut, Onnik; Butler-Browne, Gillian

2015-11-01

The effects of voluntary activity initiated in adult mdx (C57BL/10ScSc-DMD(mdx) /J) mice on skeletal and cardiac muscle function have not been studied extensively. We studied the effects of 3 months of voluntary wheel running initiated at age 7 months on hindlimb muscle weakness, increased susceptibility to muscle contraction-induced injury, and left ventricular function in mdx mice. We found that voluntary wheel running did not worsen the deficit in force-generating capacity and the force drop after lengthening contractions in either mdx mouse gender. It increased the absolute maximal force of skeletal muscle in female mdx mice. Moreover, it did not affect left ventricular function, structural heart dimensions, cardiac gene expression of inflammation, fibrosis, or remodeling markers. These results indicate that voluntary activity initiated at age 7 months had no detrimental effects on skeletal or cardiac muscles in either mdx mouse gender. © 2015 Wiley Periodicals, Inc.

Borderlines between sarcopenia and mild late-onset muscle disease

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Johanna ePalmio

2014-09-01

Full Text Available Numerous natural or disease-related alterations occur in different tissues of the body with advancing age. Sarcopenia is defined as age-related decrease of muscle mass and strength beginning in mid-adulthood and accelerating in people older than 60 years. Pathophysiology of sarcopenia involves both neural and muscle dependent mechanisms and is enhanced by multiple factors. Aged muscles show loss in fiber number, fiber atrophy and gradual increase in the number of ragged red fibers and cytochrome c oxidase-negative fibers. Generalized loss of muscle tissue and increased amount of intramuscular fat is seen on muscle imaging. However, the degree of these changes vary greatly between individuals and the distinction between normal age-related weakening of muscle strength and clinically significant muscle disease is not always obvious. Because some of the genetic myopathies can present at a very late age and be mild in severity, the correct diagnosis is easily missed. We highlight this difficult borderline zone between sarcopenia and muscle disease by two examples: LGMD1D and myotonic dystrophy type 2. Muscle MRI is a useful tool to help differentiate myopathies from sarcopenia and to reach the correct diagnosis also in the elderly.

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

Science.gov (United States)

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

2016-06-01

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

Decreasing Compensatory Ability of Concentric Ventricular Hypertrophy in Aortic-Banded Rat Hearts

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Alexandre Lewalle

2018-02-01

Full Text Available The cardiac system compensates for variations in physiological and pathophysiological conditions through a dynamic remodeling at the organ, tissue, and intracellular levels in order to maintain function. However, on longer time scales following the onset of ventricular pressure overload, such remodeling may begin to inhibit physiological function and ultimately lead to heart failure. This progression from compensatory to decompensatory behavior is poorly understood, in particular owing to the absence of a unified perspective of the concomitantly remodeling subsystems. To address this issue, the present study investigates the evolution of compensatory mechanisms, in response to overload, by integrating diffusion-tensor MRI, echocardiography, and intracellular and hemodynamic measurements within consistent computational simulations of aortic-banded rat hearts. This approach allows a comparison of the relative leverage of different cardiac properties (geometry, passive mechanical stiffness, fiber configuration, diastolic and peak calcium concentrations, calcium-binding affinity, and aortic impedance to affect cardiac contraction. Measurements indicate that, following aortic banding, an ejection fraction (EF of 75% was maintained, relative to control rats, despite significant remodeling of the left-ventricular wall thickness (increasing by ~90% over 4 weeks. Applying our framework, we identified the left-ventricular wall thickness (concentric hypertrophy and the intracellular calcium dynamics as playing the dominant roles in preserving EF acutely, whereas the significance of hypertrophy decreased subsequently. This trend suggests an increasing reliance on intracellular mechanisms (average increase ~50%, rather than on anatomical features (average decrease ~60%, to achieve compensation of pump function in the early phase of heart failure.

"Popeye muscle" morphology in OBPI elbow flexion contracture.

Science.gov (United States)

Coroneos, Christopher J; Maizlin, Zeev V; DeMatteo, Carol; Gjertsen, Deborah; Bain, James R

2015-01-01

The pathophysiology of elbow flexion contracture (EFC) in obstetrical brachial plexus injury (OBPI) is not established. In basic science models, neonatal denervation leads to impaired muscle growth. In clinical studies, diminished growth is correlated with extent of denervation, and improved with surgical repair. In EFC, the biceps are clinically short and round vs the contralateral size, termed the "Popeye muscle". The objective of this study was to determine if the biceps morphology (muscle belly and tendon length) in arms with EFC secondary to OBPI is different vs the contralateral. This is a retrospective matched-cohort study. Patients with unilateral EFC (>20°) secondary to OBPI were identified (median = 6.6 years, range = 4.7-16.8). A blinded radiologist used computed tomography to measure length of the biceps short head muscle belly, and tendon bilaterally using standardised anatomical landmarks. Twelve patients were analyzed. The biceps muscle belly in the injured arm was shorter in all patients vs contralateral, mean difference = 3.6 cm (80%), p muscle belly and overall length, but longer tendon vs normal. This is termed the "Popeye muscle" for its irregular morphology. Findings are consistent with impaired limb growth in denervation.

Quantification of the relative contribution of the different right ventricular wall motion components to right ventricular ejection fraction: the ReVISION method.

Science.gov (United States)

Lakatos, Bálint; Tősér, Zoltán; Tokodi, Márton; Doronina, Alexandra; Kosztin, Annamária; Muraru, Denisa; Badano, Luigi P; Kovács, Attila; Merkely, Béla

2017-03-27

Three major mechanisms contribute to right ventricular (RV) pump function: (i) shortening of the longitudinal axis with traction of the tricuspid annulus towards the apex; (ii) inward movement of the RV free wall; (iii) bulging of the interventricular septum into the RV and stretching the free wall over the septum. The relative contribution of the aforementioned mechanisms to RV pump function may change in different pathological conditions.Our aim was to develop a custom method to separately assess the extent of longitudinal, radial and anteroposterior displacement of the RV walls and to quantify their relative contribution to global RV ejection fraction using 3D data sets obtained by echocardiography.Accordingly, we decomposed the movement of the exported RV beutel wall in a vertex based manner. The volumes of the beutels accounting for the RV wall motion in only one direction (either longitudinal, radial, or anteroposterior) were calculated at each time frame using the signed tetrahedron method. Then, the relative contribution of the RV wall motion along the three different directions to global RV ejection fraction was calculated either as the ratio of the given direction's ejection fraction to global ejection fraction and as the frame-by-frame RV volume change (∆V/∆t) along the three motion directions.The ReVISION (Right VentrIcular Separate wall motIon quantificatiON) method may contribute to a better understanding of the pathophysiology of RV mechanical adaptations to different loading conditions and diseases.

Troponin and anti-troponin autoantibody levels in patients with ventricular noncompaction.

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Hatice Betül Erer

Full Text Available Ventricular hypertrabeculation/noncompaction is a morphologic and functional anomaly of myocardium characterized by prominent trabeculae accompanied by deep recessus. Dilated cardiomyopathy with left ventricular failure is observed in these patients, while the cause or pathophysiologic nature of this complication is not known. Anti-troponin antibodies are formed against circulating cardiac troponins after an acute coronary event or conditions associated with chronic myocyte necrosis, such as dilated cardiomyopathy. In present study, we aimed to investigate cardiac troponins and anti troponin autoantibodies in ventricular noncompaction/hypertrabeculation patients with/without reduced ejection fraction. A total of 50 patients with ventricular noncompaction and 23 healthy volunteers were included in this study. Noncompaction/hypertrabeculation was diagnosed with two-dimensional echocardiography using appropriate criteria. Depending on ejection fraction, patients were grouped into noncompaction with preserved EF (LVEF >50%, n = 24 and noncompaction with reduced EF (LVEF <35%, n = 26 groups. Troponin I, troponin T, anti-troponin I IgM and anti-troponin T IgM were measured with sandwich immunoassay method using a commercially available kit. Patients with noncompaction had significantly higher troponin I (28.98±9.21 ng/ml in NCNE group and 28.11±10.42 ng/ml in NCLE group, troponin T (22.17±6.97 pg/ml in NCNE group and 22.78±7.76 pg/ml in NCLE group and antitroponin I IgM (1.92±0.43 µg/ml in NCNE group and 1.79±0.36 µg/ml in NCLE group levels compared to control group, while antitroponin T IgM and IgG were only elevated in patients with noncompaction and reduced EF (15.81±6.52 µg/ml for IgM and 16.46±6.25 µg/ml for IgG. Elevated cardiac troponins and anti-troponin I autoantibodies were observed in patients with noncompaction preceding the decline in systolic function and could indicate ongoing myocardial damage in these patients.

Troponin and Anti-Troponin Autoantibody Levels in Patients with Ventricular Noncompaction

Science.gov (United States)

Erer, Hatice Betül; Güvenç, Tolga Sinan; Kemik, Ahu Sarbay; Yılmaz, Hale Yaka; Kul, Şeref; Altay, Servet; Sayar, Nurten; Kaya, Yüksel; Eren, Mehmet

2013-01-01

Ventricular hypertrabeculation/noncompaction is a morphologic and functional anomaly of myocardium characterized by prominent trabeculae accompanied by deep recessus. Dilated cardiomyopathy with left ventricular failure is observed in these patients, while the cause or pathophysiologic nature of this complication is not known. Anti-troponin antibodies are formed against circulating cardiac troponins after an acute coronary event or conditions associated with chronic myocyte necrosis, such as dilated cardiomyopathy. In present study, we aimed to investigate cardiac troponins and anti troponin autoantibodies in ventricular noncompaction/hypertrabeculation patients with/without reduced ejection fraction. A total of 50 patients with ventricular noncompaction and 23 healthy volunteers were included in this study. Noncompaction/hypertrabeculation was diagnosed with two-dimensional echocardiography using appropriate criteria. Depending on ejection fraction, patients were grouped into noncompaction with preserved EF (LVEF >50%, n = 24) and noncompaction with reduced EF (LVEF <35%, n = 26) groups. Troponin I, troponin T, anti-troponin I IgM and anti-troponin T IgM were measured with sandwich immunoassay method using a commercially available kit. Patients with noncompaction had significantly higher troponin I (28.98±9.21 ng/ml in NCNE group and 28.11±10.42 ng/ml in NCLE group), troponin T (22.17±6.97 pg/ml in NCNE group and 22.78±7.76 pg/ml in NCLE group) and antitroponin I IgM (1.92±0.43 µg/ml in NCNE group and 1.79±0.36 µg/ml in NCLE group) levels compared to control group, while antitroponin T IgM and IgG were only elevated in patients with noncompaction and reduced EF (15.81±6.52 µg/ml for IgM and 16.46±6.25 µg/ml for IgG). Elevated cardiac troponins and anti-troponin I autoantibodies were observed in patients with noncompaction preceding the decline in systolic function and could indicate ongoing myocardial damage in these patients. PMID:23469039

Activation patterns of Purkinje fibers during long-duration ventricular fibrillation in an isolated canine heart model.

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Tabereaux, Paul B; Walcott, Greg P; Rogers, Jack M; Kim, Jong; Dosdall, Derek J; Robertson, Peter G; Killingsworth, Cheryl R; Smith, William M; Ideker, Raymond E

2007-09-04

The roles of Purkinje fibers (PFs) and focal wave fronts, if any, in the maintenance of ventricular fibrillation (VF) are unknown. If PFs are involved in VF maintenance, it should be possible to map wave fronts propagating from PFs into the working ventricular myocardium during VF. If wave fronts ever arise focally during VF, it should be possible to map them appearing de novo. Six canine hearts were isolated, and the left main coronary artery was cannulated and perfused. The left ventricular cavity was exposed, which allowed direct endocardial mapping of the anterior papillary muscle insertion. Nonperfused VF was induced, and 6 segments of data, each 5 seconds long, were analyzed during 10 minutes of VF. During 36 segments of data that were analyzed, 1018 PF or focal wave fronts of activation were identified. In 534 wave fronts, activation was mapped propagating from working ventricular myocardium to PF. In 142 wave fronts, activation was mapped propagating from PF to working ventricular myocardium. In 342 wave fronts, activation was mapped arising focally. More than 1 of these 3 patterns could occur in the same wave front. PFs are highly active throughout the first 10 minutes of VF. In addition to retrograde propagation from the working ventricular myocardium to PFs, antegrade propagation occurs from PFs to working ventricular myocardium, which suggests PFs are important in VF maintenance. Prior plunge needle recordings in dogs indicate activation propagates from the endocardium toward the epicardium after 1 minute of VF, which suggests that focal sites on the endocardium may represent foci and not breakthrough. If so, in addition to reentry, abnormal automaticity or triggered activity may also occur during VF.

One-and-a-half ventricular repair for isolated right ventricle metastatic tumor resection after lobectomy for lung cancer.

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Shiose, Akira; Desai, Parag; Criner, Gerard J; Pai, Sheela; Steiner, Robert M; Kaiser, Larry R; Guy, T Sloane; Toyoda, Yoshiya

2014-01-01

A 77-year-old woman presented with shortness of breath 1 year after a right upper lobectomy for lung cancer. She showed a possible intracardiac metastasis on positron emission tomography scan. There was no other evidence of recurrence. The large right ventricular mass was associated with the right ventricle free wall, the apex, the papillary muscle, and the chordae to the tricuspid valve. After mass resection of the right ventricle, a one-and-a-half ventricular repair was performed with tricuspid valve replacement and defect closure. The patient was discharged on postoperative day 14 without complications and has been well for the first 3 months after the surgery.

Relationship between Fibrosis and Ventricular Arrhythmias in Chagas Heart Disease Without Ventricular Dysfunction

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Tassi, Eduardo Marinho, E-mail: etassi@ibest.com.br [Instituto de Cardiologia Edson Saad - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Continentino, Marcelo Abramoff [Hospital Frei Galvão, Guaratinguetá, SP (Brazil); Nascimento, Emília Matos do; Pereira, Basílio de Bragança [Instituto de Cardiologia Edson Saad - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Coppe - Instituto Alberto Luiz Coimbra de Pós-Graduação e Pesquisa de Engenharia - UFRJ, Rio de Janeiro, RJ (Brazil); Pedrosa, Roberto Coury [Instituto de Cardiologia Edson Saad - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil)

2014-05-15

Patients with Chagas disease and segmental wall motion abnormality (SWMA) have worse prognosis independent of left ventricular ejection fraction (LVEF). Cardiac magnetic resonance (CMR) is currently the best method to detect SWMA and to assess fibrosis. To quantify fibrosis by using late gadolinium enhancement CMR in patients with Chagas disease and preserved or minimally impaired ventricular function (> 45%), and to detect patterns of dependence between fibrosis, SWMA and LVEF in the presence of ventricular arrhythmia. Electrocardiogram, treadmill exercise test, Holter and CMR were carried out in 61 patients, who were divided into three groups as follows: (1) normal electrocardiogram and CMR without SWMA; (2) abnormal electrocardiogram and CMR without SWMA; (3) CMR with SWMA independently of electrocardiogram. The number of patients with ventricular arrhythmia in relation to the total of patients, the percentage of fibrosis, and the LVEF were, respectively: Group 1, 4/26, 0.74% and 74.34%; Group 2, 4/16, 3.96% and 68.5%; and Group 3, 11/19, 14.07% and 55.59%. Ventricular arrhythmia was found in 31.1% of the patients. Those with and without ventricular arrhythmia had mean LVEF of 59.87% and 70.18%, respectively, and fibrosis percentage of 11.03% and 3.01%, respectively. Of the variables SWMA, groups, age, LVEF and fibrosis, only the latter was significant for the presence of ventricular arrhythmia, with a cutoff point of 11.78% for fibrosis mass (p < 0.001). Even in patients with Chagas disease and preserved or minimally impaired ventricular function, electrical instability can be present. Regarding the presence of ventricular arrhythmia, fibrosis is the most important variable, its amount being proportional to the complexity of the groups.

Relationship between Fibrosis and Ventricular Arrhythmias in Chagas Heart Disease Without Ventricular Dysfunction

International Nuclear Information System (INIS)

Tassi, Eduardo Marinho; Continentino, Marcelo Abramoff; Nascimento, Emília Matos do; Pereira, Basílio de Bragança; Pedrosa, Roberto Coury

2014-01-01

Patients with Chagas disease and segmental wall motion abnormality (SWMA) have worse prognosis independent of left ventricular ejection fraction (LVEF). Cardiac magnetic resonance (CMR) is currently the best method to detect SWMA and to assess fibrosis. To quantify fibrosis by using late gadolinium enhancement CMR in patients with Chagas disease and preserved or minimally impaired ventricular function (> 45%), and to detect patterns of dependence between fibrosis, SWMA and LVEF in the presence of ventricular arrhythmia. Electrocardiogram, treadmill exercise test, Holter and CMR were carried out in 61 patients, who were divided into three groups as follows: (1) normal electrocardiogram and CMR without SWMA; (2) abnormal electrocardiogram and CMR without SWMA; (3) CMR with SWMA independently of electrocardiogram. The number of patients with ventricular arrhythmia in relation to the total of patients, the percentage of fibrosis, and the LVEF were, respectively: Group 1, 4/26, 0.74% and 74.34%; Group 2, 4/16, 3.96% and 68.5%; and Group 3, 11/19, 14.07% and 55.59%. Ventricular arrhythmia was found in 31.1% of the patients. Those with and without ventricular arrhythmia had mean LVEF of 59.87% and 70.18%, respectively, and fibrosis percentage of 11.03% and 3.01%, respectively. Of the variables SWMA, groups, age, LVEF and fibrosis, only the latter was significant for the presence of ventricular arrhythmia, with a cutoff point of 11.78% for fibrosis mass (p < 0.001). Even in patients with Chagas disease and preserved or minimally impaired ventricular function, electrical instability can be present. Regarding the presence of ventricular arrhythmia, fibrosis is the most important variable, its amount being proportional to the complexity of the groups

Assessment of left ventricular function at different levels of exercise using gold-195m in asymptomatic diabetics

International Nuclear Information System (INIS)

Fazio, F.; Margonato, A.; Gerundini, P.; Vicedomini, G.; Gilardi, M.C.; Fregoso, A.; Bencivelli, W.; Milanesi, L.; Pozza, G.

1985-01-01

Left ventricular ejection fraction (LVEF) was evaluated by gold-195m first pass ventriculography in 10 diabetic patients with microangiopathy, in 10 diabetics without any complications, and in 10 healthy controls during maximum exercise. No differences among groups were present at rest, but at maximal exercise LVEF was significantly lower in microangiopathic patients than in the other two groups. Also muscle blood flow measured by xenon-133 washout was significantly lower during exercise in microangiopathic subjects. Small-vessel involvement of myocardium and muscle could play a role in the development of cardiovascular abnormalities during exercise in diabetics

Transient severe left ventricular dysfunction following percutaneous patent ductus arteriosus closure in an adult with bicuspid aortic valve: A case report.

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Hwang, Hui-Jeong; Yoon, Kyung Lim; Sohn, Il Suk

2016-03-01

The present study reported the case of a 60-year-old female with patent ductus arteriosus (PDA) and a bicuspid aortic valve, who presented with transient severe left ventricular (LV) dysfunction following percutaneous closure of PDA, as identified by speckle tracking analysis. Transient LV dysfunction following PDA closure has previously been reported; however, severe LV dysfunction is rare. In the present case, the combination of a large PDA size, large amount of shunting, LV remodeling and bicuspid aortic valve may have induced serious deterioration of LV function following PDA closure. Furthermore, speckle-tracking echocardiography may be useful in the estimation of functional alterations in the myocardium of the LV following PDA closure. The observations detailed in the present study may improve the understanding of the pathophysiology and myocardial patterns of transient left ventricular dysfunction following PDA closure in adult humans.

Aortopathy in Congenital Heart Disease in Adults: Aortic Dilatation with Decreased Aortic Elasticity that Impacts Negatively on Left Ventricular Function.

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Niwa, Koichiro

2013-04-01

Bicuspid aortic valve and/or coarctation of the aorta are consistently associated with ascending aortic and para-coarctation medial abnormalities. Medial abnormalities in the ascending aorta are prevalent in other types of patients with a variety of forms congenital heart disease (CHD), such as single ventricle, persistent truncus arteriosus, transposition of the great arteries, hypoplastic left heart syndrome, tetralogy of Fallot. These abnormalities encompass a wide age range, and may predispose to dilatation, aneurysm, and rupture that necessitates aortic valve and root surgery. This dilatation can develop in CHD patients without stenotic region. These CHDs exhibit ongoing dilatation of the aortic root and reduced aortic elasticity and increased aortic stiffness that may relate to intrinsic properties of the aortic root. The concept of aortic dilatation is shifting a paradigm of aortic dilatation, as so called post stenotic dilatation, to primary intrinsic aortopahy. These aortic dilatation and increased stiffness can induce aortic aneurysm, rupture of the aorta and aortic regurgitation, but also provoke left ventricular hypertrophy, reduced coronary artery flow and left ventricular failure. We can recognize this association of aortic pathophysiological abnormality, aortic dilation and aorto-left ventricular interaction as a new clinical entity: "aortopathy".

Amiodarone for the treatment and prevention of ventricular fibrillation and ventricular tachycardia

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Hugo Van Herendael

2010-06-01

Full Text Available Hugo Van Herendael, Paul DorianDivision of Cardiology, St. Michael’s Hospital, University of Toronto, Toronto, CanadaAbstract: Amiodarone has emerged as the leading antiarrhythmic therapy for termination and prevention of ventricular arrhythmia in different clinical settings because of its proven efficacy and safety. In patients with shock refractory out-of-hospital cardiac arrest and hemodynamically destabilizing ventricular arrhythmia, amiodarone is the most effective drug available to assist in resuscitation. Although the superiority of the transvenous implantable cardioverter defibrillator (ICD over amiodarone has been well established in the preventive treatment of patients at high risk of life-threatening ventricular arrhythmias, amiodarone (if used with a beta-blocker is the most effective antiarrhythmic drug to prevent ICD shocks and treat electrical storm. Both the pharmacokinetics and the electrophysiologic profile of amiodarone are complex, and its optimal and safe use requires careful patient surveillance with respect to potential adverse effects.Keywords: amiodarone, ventricular fibrillation, unstable ventricular tachycardia

The overloaded right heart and ventricular interdependence.

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Naeije, Robert; Badagliacca, Roberto

2017-10-01

The right and the left ventricle are interdependent as both structures are nested within the pericardium, have the septum in common and are encircled with common myocardial fibres. Therefore, right ventricular volume or pressure overloading affects left ventricular function, and this in turn may affect the right ventricle. In normal subjects at rest, right ventricular function has negligible interaction with left ventricular function. However, the right ventricle contributes significantly to the normal cardiac output response to exercise. In patients with right ventricular volume overload without pulmonary hypertension, left ventricular diastolic compliance is decreased and ejection fraction depressed but without intrinsic alteration in contractility. In patients with right ventricular pressure overload, left ventricular compliance is decreased with initial preservation of left ventricular ejection fraction, but with eventual left ventricular atrophic remodelling and altered systolic function. Breathing affects ventricular interdependence, in healthy subjects during exercise and in patients with lung diseases and altered respiratory system mechanics. Inspiration increases right ventricular volumes and decreases left ventricular volumes. Expiration decreases both right and left ventricular volumes. The presence of an intact pericardium enhances ventricular diastolic interdependence but has negligible effect on ventricular systolic interdependence. On the other hand, systolic interdependence is enhanced by a stiff right ventricular free wall, and decreased by a stiff septum. Recent imaging studies have shown that both diastolic and systolic ventricular interactions are negatively affected by right ventricular regional inhomogeneity and prolongation of contraction, which occur along with an increase in pulmonary artery pressure. The clinical relevance of these observations is being explored. Published on behalf of the European Society of Cardiology. All rights

Surgery for ventricular tachycardia in patients undergoing surgical ventricular restoration: the Karolinska approach.

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Sartipy, Ulrik; Albåge, Anders; Insulander, Per; Lindblom, Dan

2007-09-01

This article presents a review on the efficacy of surgical ventricular restoration and direct surgery for ventricular tachycardia in patients with left ventricular aneurysm or dilated ischemic cardiomyopathy. The procedure includes a non-electrophysiologically guided subtotal endocardiectomy and cryoablation in addition to endoventricular patch plasty of the left ventricle. Coronary artery bypass surgery and mitral valve repair are performed concomitantly as needed. In our experience, this procedure yielded a 90% success rate in terms of freedom from spontaneous ventricular tachycardia, with an early mortality rate of 3.8%. A practical guide to the pre- and postoperative management of these patients is provided.

Insights into Pathophysiology from Medication-induced Tremor

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John C. Morgan

2017-10-01

Full Text Available Background: Medication-induced tremor (MIT is common in clinical practice and there are many medications/drugs that can cause or exacerbate tremors. MIT typically occurs by enhancement of physiological tremor (EPT, but not all drugs cause tremor in this way. In this manuscript, we review how some common examples of MIT have informed us about the pathophysiology of tremor.Methods: We performed a PubMed literature search for published articles dealing with MIT and attempted to identify articles that especially dealt with the medication’s mechanism of inducing tremor.Results: There is a paucity of literature that deals with the mechanisms of MIT, with most manuscripts only describing the frequency and clinical settings where MIT is observed. That being said, MIT emanates from multiple mechanisms depending on the drug and it often takes an individualized approach to manage MIT in a given patient.Discussion: MIT has provided some insight into the mechanisms of tremors we see in clinical practice. The exact mechanism of MIT is unknown for most medications that cause tremor, but it is assumed that in most cases physiological tremor is influenced by these medications. Some medications (epinephrine that cause EPT likely lead to tremor by peripheral mechanisms in the muscle (β-adrenergic agonists, but others may influence the central component (amitriptyline. Other drugs can cause tremor, presumably by blockade of dopamine receptors in the basal ganglia (dopamine-blocking agents, by secondary effects such as causing hyperthyroidism (amiodarone, or by other mechanisms. We will attempt to discuss what is known and unknown about the pathophysiology of the most common MITs.

Cortical Silent Period Reveals Differences Between Adductor Spasmodic Dysphonia and Muscle Tension Dysphonia.

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Samargia, Sharyl; Schmidt, Rebekah; Kimberley, Teresa Jacobson

2016-03-01

The pathophysiology of adductor spasmodic dysphonia (AdSD), like other focal dystonias, is largely unknown. The purposes of this study were to determine (a) cortical excitability differences between AdSD, muscle tension dysphonia (MTD), and healthy controls; (b) distribution of potential differences in cranial or skeletal muscle; and (c) if cortical excitability measures assist in the differential diagnosis of AdSD and MTD. Ten participants with adductor spasmodic dysphonia, 8 with muscle tension dysphonia, and 10 healthy controls received single and paired pulse transcranial magnetic stimulation (TMS) to the primary motor cortex contralateral to tested muscles, first dorsal interosseus (FDI), and masseter. We tested the hypothesis that cortical excitability measures in AdSD would be significantly different from those in MTD and healthy controls. In addition, we hypothesized that there would be a correlation between cortical excitability measures and clinical voice severity in AdSD. Cortical silent period duration in masseter and FDI was significantly shorter in AdSD than MTD and healthy controls. Other measures failed to demonstrate differences. There are differences in cortical excitability between AdSD, MTD, and healthy controls. These differences in the cortical measure of both the FDI and masseter muscles in AdSD suggest widespread dysfunction of the GABAB mechanism may be a pathophysiologic feature of AdSD, similar to other forms of focal dystonia. Further exploration of the use of TMS to assist in the differential diagnosis of AdSD and MTD is warranted. © The Author(s) 2015.

Effect of myocardial viability in the infarct area on regional left ventricular function

International Nuclear Information System (INIS)

Ishii, Toshihiko; Watanabe, Takeshi; Usui, Mikio; Nagai, Yoshikazu

1990-01-01

This study explored the relationship between global left ventricular ejection fraction (LVEF), regional LVEF of infarct myocardium, and the viability of the myocardium due to the development of collaterals in the infarct area. Each was evaluated by exercise thallium-201 myocardial SPECT, multigated blood pool scintigraphy and coronary angiography. A total of 68 patients with old anteroseptal myocardial infarction and 23 normal persons were studied. The patients were found to have septal defect on exercise thallium images. According to the appearance of redistribution (RD) on delayed images, the patients were classified as having positive RD (n=42, 62%) or negative RD (n=26, 38%). The global LVEF was compared with regional LVEF of the basal, middle and apical areas within septum, as calculated by multigated blood pool scintigraphy. There was no significant difference in global LVEF between the groups of positive and negative RD patients. However, regional LVEF of the basal and middle areas was significantly larger in the group of positive RD than the group of negative RD. Collaterals were significantly observed in the group of positive RD, as compared with the group of negative RD (53% vs 25%). It was more frequent in cases of higher degree of stenosis. In the group of negative RD, none of the patients had collaterals when coronary stenosis was 90% or less. Redistribution may reflect myocardial viability. Myocardial viability within the infarct area had favorable influences on the regional left ventricular function. Therefore, not only global but also regional left ventricular function is necessary for better understanding of pathophysiology of myocardial infarction.(N.K.)

[The reasonable use of right ventricular protection strategy in right ventricular outflow tract reconstruction].

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Zhang, Y; Yuan, H Y; Liu, X B; Wen, S S; Xu, G; Cui, H J; Zhuang, J; Chen, J M

2018-06-01

As a result of right ventricular outflow tract reconstruction, which is the important and basic step of complex cardiac surgery, the blood flow of right ventricular outflow tract is unobstructed, while pulmonary valve regurgitation and right heart dysfunction could be happened. These problems are often ignored in early days, more and more cases of right heart dysfunction need clinical intervention, which is quite difficult and less effective. How to protect effectively the right ventricular function is the focus. At present main methods to protect the right ventricular function include trying to avoid or reduce length of right ventricular incision, reserving or rebuilding the function of the pulmonary valve, using growth potential material for surgery. The protection of the right ventricular function is a systemic project, it involves many aspects, single measures is difficult to provide complete protection, only the comprehensive use of various protection strategy, can help to improve the long-term prognosis.

Managing the right ventricular outflow tract for pulmonary regurgitation after tetralogy of Fallot repair

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Hauser, Michael; Eicken, Andreas; Kuehn, Andreas; Hess, John; Fratz, Sohrab; Ewert, Peter; Kaemmerer, Harald

2013-01-01

The long-term outcome of patients with tetralogy of Fallot (TOF) with reconstruction of the right ventricular (RV) outflow tract is often complicated by the sequelae of severe pulmonary regurgitation. Progressive enlargement of the right ventricle, biventricular dysfunction and arrhythmia are apparent in more than 50% of the patients in the fourth decade of life. Pathophysiologic implications, clinical assessment and diagnostic modalities are discussed, whereas CMR imaging seems to be the procedure of choice. Therapeutical options for rereconstruction of the RV outflow tract are mentioned, surgical and interventional procedures are explained in detail. The optimal timing of reoperation for significant pulmonary regurgitation after TOF repair is still a matter of controversy given the limited runtime of the lately implanted prostheses and the risk of further reoperation. Early surgery is recommended in these patients before symptoms develop, or RV function has declined. Today we believe that waiting for the patient to become symptomatic is too late. All in all, pulmonary valve replacement is at least indicated in patients developing symptoms due to severe pulmonary regurgitation, particularly if associated with substantial or progressive RV dilatation, tricuspid regurgitation and/or supraventricular or ventricular arrhythmias. PMID:27326099

Impact of sympathetic innervation on recurrent life-threatening arrhythmias in the follow-up of patients with idiopathic ventricular fibrillation

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Paul, Matthias; Acil, Tayfun; Breithardt, Guenter; Wichter, Thomas [Hospital of the University of Muenster, Department of Cardiology and Angiology, Muenster (Germany); Schaefers, Michael; Kies, Peter; Schaefers, Klaus; Schober, Otmar [Hospital of the University of Muenster, Department of Nuclear Medicine, Muenster (Germany)

2006-08-15

Idiopathic ventricular fibrillation (IVF) is defined as VF in the absence of any identifiable structural or functional cardiac disease. The underlying pathophysiological mechanisms are unknown. This study was performed to investigate the potential impact of sympathetic dysfunction, assessed by {sup 123}I-meta-iodo-benzylguanidine scintigraphy ({sup 123}I-MIBG SPECT), on the long-term prognosis of patients with IVF. {sup 123}I-MIBG SPECT was performed in 20 patients (mean age 37{+-}13 years) with IVF. Mean follow-up of patients after study entry was 7.2{+-}1.5 years (range 4.9-10.5 years). Ten patients (five men, five women; mean age 43{+-}12 years; p=NS versus study group) with medullary carcinoma of the thyroid gland served as an age-matched control group. Abnormal {sup 123}I-MIBG uptake was observed in 13 patients (65%). During follow-up, 18 episodes of VF/fast polymorphic ventricular tachycardias occurred in four IVF patients with abnormal {sup 123}I-MIBG uptake whereas only two episodes of monomorphic ventricular tachycardia (and no VF) occurred in a single IVF patient with normal {sup 123}I-MIBG uptake. Impairment of sympathetic innervation may indicate a higher risk of future recurrent episodes of life-threatening ventricular tachyarrhythmias in patients with IVF. Studies in larger cohorts are required to validate the significance of {sup 123}I-MIBG SPECT during the long-term follow-up of these patients. (orig.)

Influence of glutamate-evoked pain and sustained elevated muscle activity on blood oxygenation in the human masseter muscle.

Science.gov (United States)

Suzuki, Shunichi; Arima, Taro; Kitagawa, Yoshimasa; Svensson, Peter; Castrillon, Eduardo

2017-12-01

This study aimed to investigate the effect of glutamate-evoked masseter muscle pain on intramuscular oxygenation during rest and sustained elevated muscle activity (SEMA). Seventeen healthy individuals participated in two sessions in which they were injected with glutamate and saline in random order. Each session was divided into three, 10-min periods. During the first (period 1) and the last (period 3) 10-min periods, participants performed five intercalated 1-min bouts of masseter SEMA with 1-min periods of 'rest'. At onset of the second 10-min period, glutamate (0.5 ml, 1 M; Ajinomoto, Tokyo, Japan) or isotonic saline (0.5 ml; 0.9%) was injected into the masseter muscle and the participants kept the muscle relaxed in a resting position for 10 min (period 2). The hemodynamic characteristics of the masseter muscle were recorded simultaneously during the experiment by a laser blood-oxygenation monitor. The results demonstrated that glutamate injections caused significant levels of self-reported pain in the masseter muscle; however, this nociceptive input did not have robust effects on intramuscular oxygenation during rest or SEMA tasks. Interestingly, these findings suggest an uncoupling between acute nociceptive activity and hemodynamic parameters in both resting and low-level active jaw muscles. Further studies are needed to explore the pathophysiological significance of blood-flow changes for persistent jaw-muscle pain conditions. © 2017 Eur J Oral Sci.

Update on new muscle glycogenosis

DEFF Research Database (Denmark)

Laforêt, Pascal; Malfatti, Edoardo; Vissing, John

2017-01-01

PURPOSE OF REVIEW: The field of muscle glycogenoses has progressed in recent years by the identification of new disorders, and by reaching a better understanding of pathophysiology of the disorders and the physiology of glycogen metabolism. RECENT FINDINGS: In this review, we describe the clinical...... and pathological features of the three most recently described muscle glycogenoses caused by recessive mutations in GYG1, RBCK1 and PGM1. The three involved enzymes play different roles in glycogen metabolism. Glycogenin-1 (GYG1) is involved in the initial steps of glycogen synthesis, whereas phosphoglucomutase...... with abnormal storage material in the heart, but most cases present with a polyglucosan body myopathy without cardiac involvement. SUMMARY: The recent identification of new glycogenosis not only allows to improve the knowledge of glycogen metabolism, but also builds bridges with protein glycosylation and immune...

THE STUDY OF HEART MUSCLE IN CHRONIC ALCOHOLICS

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Girish M

2016-09-01

Full Text Available BACKGROUND Alcohol affects many organs, especially the liver, pancreas and brain. Although, the beneficial effects of mild or moderate ethanol consumption have been implied with respect to coronary artery disease, excessive ethanol consumption can result in Alcoholic Heart Muscle Disease (AHMD. AIMS Alcohol consumption, mainly arrack, is common social problem in Mangalore. This study has been undertaken to assess the effects of alcohol on cardiovascular system. MATERIALS AND METHODS Thirty patient with history of consumption of about 6 units of alcohol per day for at least 5 days a week for at least 5 years who were admitted to Government Wenlock Hospital, Attavar K.M.C. and University Medical Centre, Mangalore, were selected as case and studied. RESULTS Alcohol intake is predominantly observed in males, majority of alcoholic had high blood pressure, serum levels of CPK-MB and LDH are elevated in chronic alcoholic patients, left ventricular hypertrophy, premature ventricular contraction and sinus tachycardia were common findings in the electrocardiograms of chronic alcoholic patients and development of alcoholic heart muscle disease is directly proportional to the quantity and duration of alcohol intake. CONCLUSION Overall, the present study has found high morbidity from chronic alcohol consumption highlighting the need for preventive measures to tackle this preventable hazard.

Right Ventricular Endomyocardial Fibrosis Presenting With Ventricular Tachycardia And Apical Thrombus - An Interesting Presentation

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Amitesh Aggarwal

2009-11-01

Full Text Available Endomyocardial fibrosis is a progressive disease of unknown origin affecting children and young adults. It involves inflow portion of right and/or left ventricle and apex. It may be associated with thrombus. Literature regarding right ventricular endomyocardial fibrosis with thrombus is scarce. Here we report a rare case of right ventricular endomyocardial fibrosis presenting as ventricular tachycardia and echocardiographic evidence of apical thrombus. Interestingly there was no pulmonary involvement or evidence of deep venous thrombosis. This case also underscores the importance of urgent echocardiography in diagnosis of obscure cases of ventricular tachycardia.

Decreased Muscle Strength and Quality in Diabetes-Related Dementia

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Akito Tsugawa

2017-12-01

Full Text Available Background/Aims: Diabetes-related dementia (DrD, a dementia subgroup associated with specific diabetes mellitus (DM-related metabolic abnormalities, is clinically and pathophysiologically different from Alzheimer disease (AD and vascular dementia. We determined whether skeletal muscle strength, quality, and mass decrease in individuals with DrD. Methods: We evaluated grip and knee extension strength, muscle mass, and gait speed in 106 patients with probable AD and without type 2 DM (AD[–DM] group, 74 patients with probable AD and with DM (AD[+DM] group, and 36 patients with DrD (DrD group. Muscle quality was defined as the ratio of muscle strength to muscle mass. Results: Both female and male subjects with DrD showed significantly decreased muscle strength and quality in the upper extremities compared with the subjects with AD[–DM] or AD[+DM]. Female subjects with DrD showed significantly decreased muscle quality in the lower extremities compared with the subjects with AD[–DM]. Both female and male subjects with DrD had a significantly lower gait speed compared with the subjects with AD[–DM]. However, there were no significant differences in muscle mass and the prevalence of sarcopenia between the groups. Conclusion: Subjects with DrD showed decreased muscle strength and quality, but not muscle mass, and had a low gait speed.

Experimental and clinical study on the digitalis in renal function disturbance

International Nuclear Information System (INIS)

Okubo, Mitsuru

1977-01-01

By using radioimmunoassay, movement of digoxin in the bodies of normal rabbits and dogs was discussed experimentally, and pathophysiology digoxin excretion in renal function disturbance was also discussed experimentally and clinically. The concentration of digoxin in each organ 30 minutes after intravenous administration of digoxin of 0.5 mg/kg to normal rabbits was the highest in the kidney, and it was high in order of skeletal muscles, ventricular muscles, and auricular muscles. A significant positive correlation was recognized between concentration of digoxin in blood and that in ventricular muscles. Digoxin clearance showed high values in normal dogs and dogs whose single kidney were extracted, when the concentration of digoxin in blood was low. A significant correlation between the concentration of digoxin in blood and BUN or creatinine was not recognized in patients with renal diseases, but a significant negative correlation between the concentration of digoxin in blood and creatinine clearance and between urinary excretion of digoxin and creatinine clearance was recognized. Therefore, creatinine clearance was thought to be useful for index to determine the administration dose of digoxin in renal dysfunction. In the patients who received external dialysis, decrease of the concentration of digoxin in blood after intravenous administration of digoxin delayed significantly in contrast to that of normal control group. (Tsunoda, M.)

Right Ventricular Outflow Tract Tachycardia with Structural Abnormalities of the Right Ventricle and Left Ventricular Diverticulum

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Bortolo Martini

2015-01-01

Full Text Available A 43-year-old woman presented to the emergency room with a sustained ventricular tachycardia (VT. ECG showed a QRS in left bundle branch block morphology with inferior axis. Echocardiography, ventricular angiography, and cardiac magnetic resonance imaging (CMRI revealed a normal right ventricle and a left ventricular diverticulum. Electrophysiology studies with epicardial voltage mapping identified a large fibrotic area in the inferolateral layer of the right ventricular wall and a small area of fibrotic tissue at the anterior right ventricular outflow tract. VT ablation was successfully performed with combined epicardial and endocardial approaches.

Radionuclide analysis of right and left ventricular response to exercise in patients with atrial and ventricular septal defects

International Nuclear Information System (INIS)

Peter, C.A.; Bowyer, K.; Jones, R.H.

1983-01-01

In patients with ventricular or atrial septal defect, the ventricle which is chronically volume overloaded might not appropriately respond to increased demand for an augmentation in output and thereby might limit total cardiac function. In this study we simultaneously measured right and left ventricular response to exercise in 10 normal individuals, 10 patients with ventricular septal defect (VSD), and 10 patients with atrial septal defect (ASD). The normal subjects increased both right and left ventricular ejection fraction, end-diastolic volume, and stroke volume to achieve a higher cardiac output during exercise. Patients with VSD failed to increase right ventricular ejection fraction, but increased right ventricular end-diastolic volume and stroke volume. Left ventricular end-diastolic volume did not increase in these patients but ejection fraction, stroke volume, and forward left ventricular output achieved during exercise were comparable to the response observed in healthy subjects. In the patients with ASD, no rest-to-exercise change occurred in either right ventricular ejection fraction, end-diastolic volume, or stroke volume. In addition, left ventricular end-diastolic volume failed to increase, and despite an increase in ejection fraction, left ventricular stroke volume remained unchanged from rest to exercise. Therefore, cardiac output was augmented only by the heart rate increase in these patients. Right ventricular function appeared to be the major determinant of total cardiac output during exercise in patients with cardiac septal defects and left-to-right shunt

Heart Failure with Preserved Ejection Fraction – Concept, Pathophysiology, Diagnosis and Challenges for Treatment

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Lidija Veterovska Miljkovik

2015-07-01

Full Text Available Heart failure (HF with preserved left ventricular (LV ejection fraction (HFpEF occurs in 40 to 60% of the patients with HF, with a prognosis which is similar to HF with reduced ejection fraction (HFrEF. HFpEF pathophysiology is different from that of HFrEF, and has been characterized with diastolic dysfunction. Diastolic dysfunction has been defined with elevated left ventricular stiffness, prolonged iso-volumetric LV relaxation, slow LV filing and elevated LV end-diastolic pressure. Arterial hypertension occurs in majority cases with HFpEF worldwide. Patients are mostly older and obese. Diabetes mellitus and atrial fibrillation appear proportionally in a high frequency of patients with HFpEF. The HFpEF diagnosis is based on existence of symptoms and signs of heart failure, normal or approximately normal ejection and diagnosing of LV diastolic dysfunction by means of heart catheterization or Doppler echocardiography and/or elevated concentration of plasma natriuretic peptide. The present recommendations for HFpEF treatment include blood pressure control, heart chamber frequency control when atrial fibrillation exists, in some situations even coronary revascularization and an attempt for sinus rhythm reestablishment. Up to now, it is considered that no medication or a group of medications improve the survival of HFpEF patients. Due to these causes and the bad prognosis of the disorder, rigorous control is recommended of the previously mentioned precipitating factors for this disorder. This paper presents a universal review of the most important parameters which determine this disorder.

Right ventricular pressure response to exercise in adults with isolated ventricular septal defect closed in early childhood.

Science.gov (United States)

Moller, Thomas; Lindberg, Harald; Lund, May Brit; Holmstrom, Henrik; Dohlen, Gaute; Thaulow, Erik

2018-06-01

We previously demonstrated an abnormally high right ventricular systolic pressure response to exercise in 50% of adolescents operated on for isolated ventricular septal defect. The present study investigated the prevalence of abnormal right ventricular systolic pressure response in 20 adult (age 30-45 years) patients who underwent surgery for early ventricular septal defect closure and its association with impaired ventricular function, pulmonary function, or exercise capacity. The patients underwent cardiopulmonary tests, including exercise stress echocardiography. Five of 19 patients (26%) presented an abnormal right ventricular systolic pressure response to exercise ⩾ 52 mmHg. Right ventricular systolic function was mixed, with normal tricuspid annular plane systolic excursion and fractional area change, but abnormal tricuspid annular systolic motion velocity (median 6.7 cm/second) and isovolumetric acceleration (median 0.8 m/second2). Left ventricular systolic and diastolic function was normal at rest as measured by the peak systolic velocity of the lateral wall and isovolumic acceleration, early diastolic velocity, and ratio of early diastolic flow to tissue velocity, except for ejection fraction (median 53%). The myocardial performance index was abnormal for both the left and right ventricle. Peak oxygen uptake was normal (mean z score -0.4, 95% CI -2.8-0.3). There was no association between an abnormal right ventricular systolic pressure response during exercise and right or left ventricular function, pulmonary function, or exercise capacity. Abnormal right ventricular pressure response is not more frequent in adult patients compared with adolescents. This does not support the theory of progressive pulmonary vascular disease following closure of left-to-right shunts.

Four cases of right ventricular dysplasia

International Nuclear Information System (INIS)

Takamura, Ichiro; Ando, Joji; Miyamoto, Atsushi; Kobayashi, Takeshi; Sakamoto, Sanya; Yasuda, Hisakazu

1985-01-01

Finding of 81 Kr right ventriculography and 201 Tl myocardial perfusion imaging in 4 patients with right ventricular dysplasia (RVD) were compared with those in 28 patients with dilated cardiomyopathy. Remarkably dilated right ventricle was detected on 201 Tl myocardial perfusion imaging in the RVD group. In a patient with RVD who died suddenly, perfusion defect of the left ventricular myocardium, a decreased right ventricular ejection fraction, and an increased right ventricular end diastolic volume were seen. Perfusion defect of the left ventricular myocardium was seen in 10 of the 28 patients with dilated cardiomyopathy, 4 of whom died suddenly. In these 4 patients, a decreased left ventricular ejection fraction and an increased right ventricular end diastolic volume were seen. These findings obtained by the radionuclide techniques suggested that there are differences in cardiac dysfunction of the both ventricles between the groups with RVD and dilated cardiomyopathy. (Namekawa, K.)

Evaluation of normal masseter muscles on ultrasonography

International Nuclear Information System (INIS)

Hwang, Hyoung Zoo; Kim, Gyu Tae; Choi, Yong Suk; Hwang, Eui Hwan

2008-01-01

To assess the internal echo intensity and morphological variability of masseter muscles on ultrasonography and to establish diagnostic criterion of estimation. Participants consisted of 50 young adults (male 25, female 25) without pathologic conditions and with full natural dentitions. Sonographic examinations were done with real time ultrasound equipment as Logiq 500 (GE Medical Systems, Seoul, Korea) at 3 parts according to lines paralleling with ala-tragus line as reference line. The thickness and area of masseter muscles according to reference line in cross-sectional images were measured at rest and at maximum contraction. The visibility and width of the internal echogenic intensity of the masseter muscles were also assessed and the muscle appearance was classified into 4 types. Data were statistically analyzed by paired t-test and x2-test. 1. When comparing the thickness and area of masseter muscles concerning with gender, there was few significant difference between right and left sides, however, there were significant differences between males and females except for the greatest thickness of left side. 2. The changes of the greatest thickness and the area between rest and maximum contraction showed that the part of the least thickness manifested more increase at maximum contraction. 3. Each part the manifestations of the internal echogenic intensity of the masseter muscles were different depending on the locations. But there was no statistically significance. Changes of muscles thickness with contraction and internal echogenic intensity with locations showed great disparity within the masseter muscles, which will be diagnostic criteria for pathophysiologic and anatomic changes of masseter muscles.

Apical ballooning syndrome complicated by acute severe mitral regurgitation with left ventricular outflow obstruction – Case report

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Celermajer David S

2007-02-01

Full Text Available Abstract Background Apical ballooning syndrome (or Takotsubo cardiomyopathy is a syndrome of transient left ventricular apical ballooning. Although first described in Japanese patients, it is now well reported in the Caucasian population. The syndrome mimicks an acute myocardial infarction but is characterised by the absence of obstructive coronary disease. We describe a serious and poorly understood complication of Takotsubo cardiomyopathy. Case Presentation We present the case of a 65 year-old lady referred to us from a rural hospital where she was treated with thrombolytic therapy for a presumed acute anterior myocardial infarction. Four hours after thrombolysis she developed acute pulmonary oedema and a new systolic murmur. It was presumed she had acute mitral regurgitation secondary to a ruptured papillary muscle, ischaemic dysfunction or an acute ventricular septal defect. Echocardiogram revealed severe mitral regurgitation, left ventricular apical ballooning, and systolic anterior motion of the mitral valve with significant left ventricular outflow tract gradient (60–70 mmHg. Coronary angiography revealed no obstructive coronary lesions. She had an intra-aortic balloon pump inserted with no improvement in her parlous haemodynamic state. We elected to replace her mitral valve to correct the outflow tract gradient and mitral regurgitation. Intra-operatively the mitral valve was mildly myxomatous but there were no structural abnormalities. She had a mechanical mitral valve replacement with a 29 mm St Jude valve. Post-operatively, her left ventricular outflow obstruction resolved and ventricular function returned to normal over the subsequent 10 days. She recovered well. Conclusion This case represents a serious and poorly understood association of Takotsubo cardiomyopathy with acute pulmonary oedema, severe mitral regurgitaton and systolic anterior motion of the mitral valve with significant left ventricular outflow tract obstruction. The

Large right ventricular sinusoids in an infant with aorta-left ventricular tunnel and proximal right coronary artery atresia.

Science.gov (United States)

Chen, Peter C; Spinner, Joseph A; Heinle, Jeffrey S

2018-07-01

We report a 1-month-old infant diagnosed with an aorta-left ventricular tunnel, ventricular septal defect, and right coronary atresia with right ventricular sinusoids. The patient's anatomy and physiology did not indicate right-ventricular-dependent coronary circulation, and therefore right ventricular decompression could be performed without compromising coronary perfusion during surgical correction. A detailed understanding of the coronary anatomy is critical in managing this defect when coronary anomalies are present.

Efeitos da estimulação ventricular convencional em pacientes com função ventricular normal Efectos de la estimulación ventricular convencional en pacientes con función ventricular normal Conventional ventricular stimulation effects on patients with normal ventricular function

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Luiz Antonio Batista de Sá

2009-08-01

Full Text Available FUNDAMENTO: A estimulação de ventrículo direito pode ser deletéria em pacientes com disfunção ventricular, entretanto há poucas evidências sobre o impacto dessa estimulação em pacientes com função normal. OBJETIVO: Avaliar a evolução clínica e laboratorial de pacientes com função ventricular normal submetidos a implante de marcapasso cardíaco artificial. MÉTODOS: Foram estudados de forma prospectiva 16 pacientes com os seguintes critérios de inclusão: função ventricular normal definida pelo ecocardiograma e presença de estimulação ventricular superior 90% (avaliação por telemetria do gerador. Parâmetros analisados: classe funcional (CF, teste de caminhada, dosagem de BNP, ecocardiograma (convencional e parâmetros de dessincronia intraventricular e teste de qualidade de vida (SF36. Essas medidas fora feitas com 10 dias(d (t1, 120d(t2 e 240 d(t3. Os dados foram comparados ao longo do tempo segundo método ANOVA. Comparações múltiplas de médias foram efetuadas utilizando-se o método de Tukey. RESULTADOS: Dos dados avaliados os seguintes não apresentaram variação estatística significante (p>0,05: classe funcional, dosagem de BNP, parâmetros ecocardiográficos convencionais, dessincronia intraventricular (Doppler tecidual. Apresentaram piora (pFUNDAMENTO: La estimulación del ventrículo derecho puede ser dañosa a pacientes con disfunción ventricular. Sin embargo, hay pocas evidencias sobre el impacto de esa estimulación en pacientes con función normal. OBJETIVO: Evaluar la evolución clínica y laboratorial de pacientes con función ventricular normal sometidos a implante de marcapaso cardíaco artificial. MÉTODOS: Se estudiaron de forma prospectiva a 16 pacientes con los siguientes criterios de inclusión: función ventricular normal definida por el ecocardiograma y presencia de estimulación ventricular superior a 90% (evaluación por telemetría del generador. Parámetros analizados: clase funcional

Cervico-mandibular muscle activity in females with chronic cervical pain

OpenAIRE

T. Lang; R. Parker; T. Burgess

2013-01-01

Pathophysiological mechanisms behind pain in chroniccervical musculoskeletal conditions (MSC) in office workers remainunclear. Chronic cervical pain has established links with temporomandibular(TM) disorders. Yet there is no current published evidence to reportwhether individuals with cervical dysfunction exhibit altered masseterand cervical extensor (CE) muscle activity. Objective: To explore CE andmasseter surface electromyographic (sEMG) activity and teeth clenchinghabits in females with c...

Clinical manifestations and pathophysiology of lissencephaly

International Nuclear Information System (INIS)

Oi, Shizuo; Sasaki, Koji; Yamada, Hiroshi; Ando, Shoko; Tamura, Yasunori; Fukuda, Kuniaki; Furukawa, Seikyo; Matsumoto, Satoshi.

1985-01-01

Four cases of lissencephaly were analyzed in light of clinical manifestations, CT findings and the state of hydrocephalus. Lissencephaly had been diagnosed mainly by autopsy until CT scan was introduced in the early 1970's. Since then, diagnosis of lissencephaly early in life is possible. Presently the major interest in this congenital CNS anomaly, which is caused by a neuronal migration disorder in the relatively late stages of fetal development, is to learn the dynamic pathophysiological state and management. The purpose of this paper is to analyze those points of lissencephaly in diagnosis during life and possible treatment in the hydrocephalic state. The common findings in CT in all four cases are as follows: No. 1. smooth cortical surface (agyria--pachygyria), No. 2. wide sylvian fissure (complete or incomplete lack of opercularization, No. 3. ventricular dilatation (remarkable bilateral enlargement of lateral ventricle and third ventricle--colpocephaly), No. 4. wide subdural or subarachnoid space in supratentorial region, No. 5. periventricular low density, No. 6. midline cavum, No. 7. normal CT findings in posterior fossa structure. Three out of four patients demonstrated full or bulged and tense anterior fontanella. Because of this suggestion of increased intracranial pressure and enlarged ventricles with periventricular lucency in CT findings, one patient underwent CT cisternography for dynamic analysis of the CSF circulation and continuous ICP monitoring for dynamic evaluation of the ICP pattern. The results revealed very much delayed CSF circulation and intermittently increased. ICP, with pressure waves appearing in 35.7 % of all recordings. (J.P.N.)

Single sodium channels from human skeletal muscle in planar lipid bilayers: characterization and response to pentobarbital

NARCIS (Netherlands)

Wartenberg, Hans C.; Urban, Bernd W.

2004-01-01

PURPOSE: To investigate the response to general anesthetics of different sodium-channel subtypes, we examined the effects of pentobarbital, a close thiopental analogue, on single sodium channels from human skeletal muscle and compared them to existing data from human brain and human ventricular

Stroke MRI: pathophysiology, potential and perspectives

International Nuclear Information System (INIS)

Fiehler, J.; Kucinski, T.; Zeumer, H.

2004-01-01

Magnetic resonance imaging (MRT) is increasingly utilized as the primary imaging modality in major stroke centers. The ability to depict several aspects of individual pathophysiology makes the use of MRI in stroke both attractive and complex. Profound knowledge of the pathophysiology of the imaging findings is crucial for a rational diagnostic workup. The pathophysiology of MRI in stroke will be reviewed considering recent experiences in clinical application, and the potential of stroke MRI will be assessed. Further perspectives like application of 'blood oxygen level dependent' (BOLD) and the use of multiparametric prediction maps will be discussed. (orig.) [de

Role of ventricular tachycardia ablation in arrhythmogenic right ventricular cardiomyopathy

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Alberto Cipriani

2017-11-01

Full Text Available Arrhythmogenic right ventricular cardiomyopathy (ARVC is characterized by progressive fibro-fatty replacement of the myocardium that represents the substrate for recurrent sustained ventricular tachycardia (VT. These arrhythmias characterize the clinical course of a sizeable proportion of patients and have significant implications for their quality of life and long-term prognosis. Antiarrhythmic drugs are often poorly tolerated and usually provide incomplete control of arrhythmia relapses. Catheter ablation is a potentially effective strategy to treat frequent VT episodes and ICD shocks in ARVC patients. The aims of this review are to discuss the electrophysiological and electroanatomic substrates of ventricular tachycardia in patients with ARVC and to analyze the role of catheter ablation in their management with particular reference to selection of patients, technical issues, potential complications and outcomes.

Understanding Muscle Dysfunction in Chronic Fatigue Syndrome

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Gina Rutherford

2016-01-01

Full Text Available Introduction. Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME is a debilitating disorder of unknown aetiology, characterised by severe disabling fatigue in the absence of alternative diagnosis. Historically, there has been a tendency to draw psychological explanations for the origin of fatigue; however, this model is at odds with findings that fatigue and accompanying symptoms may be explained by central and peripheral pathophysiological mechanisms, including effects of the immune, oxidative, mitochondrial, and neuronal pathways. For example, patient descriptions of their fatigue regularly cite difficulty in maintaining muscle activity due to perceived lack of energy. This narrative review examined the literature for evidence of biochemical dysfunction in CFS/ME at the skeletal muscle level. Methods. Literature was examined following searches of PUB MED, MEDLINE, and Google Scholar, using key words such as CFS/ME, immune, autoimmune, mitochondria, muscle, and acidosis. Results. Studies show evidence for skeletal muscle biochemical abnormality in CFS/ME patients, particularly in relation to bioenergetic dysfunction. Discussion. Bioenergetic muscle dysfunction is evident in CFS/ME, with a tendency towards an overutilisation of the lactate dehydrogenase pathway following low-level exercise, in addition to slowed acid clearance after exercise. Potentially, these abnormalities may lead to the perception of severe fatigue in CFS/ME.

Dynamic Changes of QRS Morphology of Premature Ventricular Contractions During Ablation in the Right Ventricular Outflow Tract: A Case Report.

Science.gov (United States)

Yue-Chun, Li; Jia-Feng, Lin; Jia-Xuan, Lin

2015-10-01

Electrocardiographic characteristics can be useful in differentiating between right ventricular outflow tract (RVOT) and aortic sinus cusp (ASC) ventricular arrhythmias. Ventricular arrhythmias originating from ASC, however, show preferential conduction to RVOT that may render the algorithms of electrocardiographic characteristics less reliable. Even though there are few reports describing ventricular arrhythmias with ASC origins and endocardial breakout sites of RVOT, progressive dynamic changes in QRS morphology of the ventricular arrhythmias during ablation obtained were rare.This case report describes a patient with symptomatic premature ventricular contractions of left ASC origin presenting an electrocardiogram (ECG) characteristic of right ventricular outflow tract before ablation. Pacing at right ventricular outflow tract reproduced an excellent pace map. When radiofrequency catheter ablation was applied to the right ventricular outflow tract, the QRS morphology of premature ventricular contractions progressively changed from ECG characteristics of right ventricular outflow tract origin to ECG characteristics of left ASC origin.Successful radiofrequency catheter ablation was achieved at the site of the earliest ventricular activation in the left ASC. The distance between the successful ablation site of the left ASC and the site with an excellent pace map of the RVOT was 20 mm.The ndings could be strong evidence for a preferential conduction via the myocardial bers from the ASC origin to the breakout site in the right ventricular outflow tract. This case demonstrates that ventricular arrhythmias with a single origin and exit shift may exhibit QRS morphology changes.

Near-infrared spectroscopy and skeletal muscle oxidative function in vivo in health and disease: a review from an exercise physiology perspective

Science.gov (United States)

Grassi, Bruno; Quaresima, Valentina

2016-09-01

In most daily activities related to work or leisure, the energy for muscle work substantially comes from oxidative metabolism. Functional limitations or impairments of this metabolism can significantly affect exercise tolerance and performance. As a method for the functional evaluation of skeletal muscle oxidative metabolism, near-infrared spectroscopy (NIRS) has important strengths but also several limitations, some of which have been overcome by recent technological developments. Skeletal muscle fractional O2 extraction, the main variable which can be noninvasively evaluated by NIRS, is the result of the dynamic balance between O2 utilization and O2 delivery; it can yield relevant information on key physiological and pathophysiological mechanisms, relevant in the evaluation of exercise performance and exercise tolerance in healthy subjects (in normal and in altered environmental conditions) and in patients. In the right hands, NIRS can offer insights into the physiological and pathophysiological adaptations to conditions of increased O2 needs that involve, in an integrated manner, different organs and systems of the body. In terms of patient evaluation, NIRS allows determination of the evolution of the functional impairments, to identify their correlations with clinical symptoms, to evaluate the effects of therapeutic or rehabilitative interventions, and to gain pathophysiological and diagnostic insights.

Near-infrared spectroscopy and skeletal muscle oxidative function in vivo in health and disease: a review from an exercise physiology perspective.

Science.gov (United States)

Grassi, Bruno; Quaresima, Valentina

2016-09-01

In most daily activities related to work or leisure, the energy for muscle work substantially comes from oxidative metabolism. Functional limitations or impairments of this metabolism can significantly affect exercise tolerance and performance. As a method for the functional evaluation of skeletal muscle oxidative metabolism, near-infrared spectroscopy (NIRS) has important strengths but also several limitations, some of which have been overcome by recent technological developments. Skeletal muscle fractional O2 extraction, the main variable which can be noninvasively evaluated by NIRS, is the result of the dynamic balance between O2 utilization and O2 delivery; it can yield relevant information on key physiological and pathophysiological mechanisms, relevant in the evaluation of exercise performance and exercise tolerance in healthy subjects (in normal and in altered environmental conditions) and in patients. In the right hands, NIRS can offer insights into the physiological and pathophysiological adaptations to conditions of increased O2 needs that involve, in an integrated manner, different organs and systems of the body. In terms of patient evaluation, NIRS allows determination of the evolution of the functional impairments, to identify their correlations with clinical symptoms, to evaluate the effects of therapeutic or rehabilitative interventions, and to gain pathophysiological and diagnostic insights.

Left Ventricular Function and Physiological Performance in Female Ironman Athletes and Female Police Officers.

Science.gov (United States)

Leischik, Roman; Foshag, Peter; Strauss, Markus; Spelsberg, Norman

2016-06-01

Data about physiological performance of female ironman triathletes are rare. However, some studies have reported this endurance sport may cause damage to the right or left ventricles, even in females. The goal of this study was to assess prospectively the right/left ventricular function and physiological performance in female athletes (middle- and long ironman distance) and to compare the findings to female federal police officers. A total of 33 female triathletes and 37 female police officers were examined using spiro-ergometry and echocardiography. Female triathletes achieved VO2max 52.8 ± 5.7 ml/kg(-1)·min(-1), and police officers 35.3 ± 6.5 ml/kg(-1)·min(-1) In athletes, left ventricular end-diastolic diameter was 4.4 ± 0.3 cm and in police officers 4.5 ± 0.4 cm, and the left ventricular muscle mass index was 85.8 g/m(2 )± 18.7 in athletes and in police officers 72.0 g/m(2 )± 9.1. Right ventricular area change among athletes was 49.4 ± 8.5%, and in police officers 46.0 ± 6.9%. The performance date of female triathletes can be used as training prescription for leisure female triathletes, when middle or long distances in triathlon competitions are planned. No right or left ventricular dysfunction was found despite long training and finishing of long distance competitions: non-elite athletes, 5.4 ± 2.8 years of triathlon competitions; elite athletes, 7.6 ± 5.8 years. © The Author(s) 2016.

Quantitative evaluation of muscle perfusion with CEUS and with MR

International Nuclear Information System (INIS)

Weber, Marc-Andre; Delorme, Stefan; Krix, Martin

2007-01-01

Functional imaging might increase the role of imaging in muscular diseases, since alterations of muscle morphology alone are not specific for a particular disease. Perfusion, i.e., the blood flow per tissue and time unit including capillary flow, is an important functional parameter. Pathological changes of skeletal muscle perfusion can be found in various clinical conditions, such as degenerative or inflammatory myopathies or peripheral arterial occlusive disease. This article reviews the theoretical basics of functional radiological techniques for assessing skeletal muscle perfusion and focuses on contrast-enhanced ultrasound (CEUS) and magnetic resonance imaging (MRI) techniques. Also, the applications of microvascular imaging, such as in detection of myositis and for discriminating myositis from other myopathies or evaluating peripheral arterial occlusive disease, are presented, and possible clinical indications are discussed. In conclusion, dedicated MR and CEUS methods are now available that visualize and quantify (patho-)physiologic information about microcirculation within skeletal muscles in vivo and hence establish a useful diagnostic tool for muscular diseases. (orig.)

Quantitative evaluation of muscle perfusion with CEUS and with MR

Energy Technology Data Exchange (ETDEWEB)

Weber, Marc-Andre; Delorme, Stefan [German Cancer Research Centre, Department of Radiology, Heidelberg (Germany); Krix, Martin [German Cancer Research Centre, Department of Radiology, Heidelberg (Germany); Bracco ALTANA Pharma GmbH, Konstanz (Germany)

2007-10-15

Functional imaging might increase the role of imaging in muscular diseases, since alterations of muscle morphology alone are not specific for a particular disease. Perfusion, i.e., the blood flow per tissue and time unit including capillary flow, is an important functional parameter. Pathological changes of skeletal muscle perfusion can be found in various clinical conditions, such as degenerative or inflammatory myopathies or peripheral arterial occlusive disease. This article reviews the theoretical basics of functional radiological techniques for assessing skeletal muscle perfusion and focuses on contrast-enhanced ultrasound (CEUS) and magnetic resonance imaging (MRI) techniques. Also, the applications of microvascular imaging, such as in detection of myositis and for discriminating myositis from other myopathies or evaluating peripheral arterial occlusive disease, are presented, and possible clinical indications are discussed. In conclusion, dedicated MR and CEUS methods are now available that visualize and quantify (patho-)physiologic information about microcirculation within skeletal muscles in vivo and hence establish a useful diagnostic tool for muscular diseases. (orig.)

Left ventricular function in right ventricular overload

International Nuclear Information System (INIS)

Iwanaga, Shiro; Handa, Shunnosuke; Abe, Sumihisa; Onishi, Shohei; Nakamura, Yoshiro; Kunieda, Etsuo; Ogawa, Koichi; Kubo, Atsushi

1989-01-01

This study clarified regional and global functions of the distorted left ventricle due to right ventricular overload by gated radionuclide ventriculography (RNV). Cardiac catheterization and RNV were performed in 13 cases of atrial septal defect (ASD), 13 of pure mitral stenosis (MS), 10 of primary pulmonary hypertension (PPH), and 10 of normal subjects (NL). Right ventricular systolic pressure (RVSP) was 32.9±13.9, 45.0±12.2, 88.3±17.1, and 21.2±4.5 mmHg, respectively. The end-systolic LAO view of the left ventricle was halved into septal and free-wall sides. The end-diastolic halves were determined in the same plane. Ejection fractions of the global left ventricle (LVEF), global right ventricle (RVEF), the septal half of the left ventricle (SEPEF), and the free-wall half of the left ventricle (FWEF) were obtained. LVEF was 56.8±9.8% in NL, 52.8±10.5% in ASD, and 49.5±12.9% in PPH. In MS, LVEF (47.0±13.0%) was smaller than those in the other groups. RVEF was 37.0±5.2% in NL, 43.7±15.5% in ASD, and 32.8±11.5% in MS. In PPH, RVEF (25.0±10.6%) was smaller than those in the other groups. SEPEF was smaller in ASD (42.5±13.2%), MS (40.4±13.1%), PPH (40.5±12.5%) than in NL (53.5±8.5%). Systolic function of the septal half of the left ventricle was disturbed by right ventricular overload. RVEF (r=-0.35, p<0.05) and SEPEF (r=-0.51, p<0.01) had negative correlations with RVSP. As RVSP rose, systolic function of the septal half of the left ventricle was more severely disturbed. FWEF was the same among the four groups; NL (57.0±12.6%), ASD (48.6±15.2%), MS (50.5±12.0%), and PPH (51.1±12.3%). There was a good correlation between SEPEF and LVEF in NL (r=0.81), although in PPH this correlation was poor (r=0.64). These data showed that the distorted left ventricular due to right ventricular overload maintains its global function with preserved function of the free-wall side. (J.P.N.)

Measurement of ventricular function using Doppler ultrasound

International Nuclear Information System (INIS)

Teague, S.M.

1986-01-01

Doppler has wide application in the evaluation of valvular heart disease. The need to know ventricular function is a much more common reason for an echocardiographic evaluation. Interestingly, Doppler examinations can assess ventricular function from many perspectives. Description of ventricular function entails measurement of the timing, rate and volume of ventricular filling and ejection. Doppler ultrasound examination reveals all of these aspects of ventricular function noninvasively, simply, and without great expense or radiation exposure, as described in this chapter

Right ventricular function in patients with ischemic heart disease

International Nuclear Information System (INIS)

Araki, Haruo; Hisano, Ryuichi; Nagata, Yoshiyuki; Caglar, N.; Nakamura, Motoomi

1985-01-01

Thirty-five patients with ischemic heart disease (IHD) and 10 normal subjects were studied. Right and left ventricular ejecction fractions (EF) were determined using equilibrium radionuclide ventriculography with technetium-99m. Furthermore, abnormal motion of the right ventricular septal wall was obtained by cardiac cathetelization, and its relation to the right ventricular EF was examined. In IHD patients with anterior myocardial infarction, left ventricular EF decreased, but right ventricular EF was normal. This suggested that left ventricular dysfunction does not always have an effect on right ventricular function. Right ventricular EF was normal even when akinesis or dyskinesis was present in the ventricular septul, suggesting that abnormal motion of the ventricular septal wall has no significantly stimulant effect on right ventricular function. A decreased right ventricular EF was likely to occur only when the right ventricular free wall became ischemic or necrotic simultaneously with occurrence of posterior myocardial infarction. (Namekawa, K.)

Coronary oscillatory flow amplitude is more affected by perfusion pressure than ventricular pressure.

Science.gov (United States)

Krams, R; Sipkema, P; Westerhof, N

1990-06-01

In this study on the isolated, maximally vasodilated, blood-perfused cat heart we investigated the relation between left ventricular developed pressure (delta Piv) and coronary oscillatory flow amplitude (diastolic minus systolic flow, delta F) at different levels of constant perfusion pressure (Pp). We hypothesized that the effect of cardiac contraction on the phasic flow results from the changing elastic properties of cardiac muscle. The coronary vessel compartment can, as can the left ventricular lumen compartment, be described by a time-varying elastance. This concept predicts that the effect of left ventricular pressure on delta F is small, whereas the effect of Pp is considerable. Both the waterfall model and the intramyocardial pump model predict the inverse. The relation between delta Piv and delta F at a Pp of 10 kPa is delta F = (4.71 +/- 3.08).delta Piv + 337 +/- 75 (slope in ml.min-1.100 g-1.kPa-1 and intercept in ml.min-1.100 g-1; n = 7); the relation between (constant levels of) Pp and delta F at a constant delta Piv of 10 kPa is delta F = 51.Pp + 211 (slope in ml.min-1.100 g-1.kPa-1 and intercept in ml.min-1.100 g-1; n = 6). The differences in slope are best predicted by the time-varying elastance concept.

The Prognostic Value of Left Atrial Peak Reservoir Strain in Acute Myocardial Infarction Is Dependent on Left Ventricular Longitudinal Function and Left Atrial Size

DEFF Research Database (Denmark)

Ersbøll, Mads; Andersen, Mads J; Valeur, Nana

2013-01-01

of PALS and left ventricular longitudinal strain (global longitudinal strain) in large-scale populations in regard to prognosis. METHODS AND RESULTS: We prospectively included 843 patients (mean age 62.1+/-11.8; 74% male) with acute myocardial infarction and measured global longitudinal strain, left......BACKGROUND: Peak atrial longitudinal strain (PALS) during the reservoir phase has been proposed as a measure of left atrium function in a range of cardiac conditions, with the potential for added pathophysiological insight and prognostic value. However, no studies have assessed the interrelation...

Right ventricular failure after implantation of a continuous-flow left ventricular assist device

DEFF Research Database (Denmark)

Cordtz, Johan Joakim; Nilsson, Jens C; Hansen, Peter B

2014-01-01

Right ventricular failure (RVF) is a significant complication after implantation of a left ventricular assist device. We aimed to identify haemodynamic changes in the early postoperative phase that predicted subsequent development of RVF in a cohort of HeartMate II (HMII) implanted patients....

Longitudinal muscle dysfunction in achalasia esophagus and its relevance.

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Mittal, Ravinder K; Hong, Su Jin; Bhargava, Valmik

2013-04-01

Muscularis propria of the esophagus is organized into circular and longitudinal muscle layers. Goal of this review is to summarize the role of longitudinal muscle in physiology and pathophysiology of esophageal sensory and motor function. Simultaneous manometry and ultrasound imaging that measure circular and longitudinal muscle contraction respectively reveal that during peristalsis 2 layers of the esophagus contract in perfect synchrony. On the other hand, during transient relaxation of the lower esophageal sphincter (LES), longitudinal muscle contracts independently of circular muscle. Recent studies provide novel insights, i.e., longitudinal muscle contraction of the esophagus induces LES relaxation and possibly descending relaxation of the esophagus. In achalasia esophagus and other motility disorders there is discoordination between the 2 muscle layers. Longitudinal muscle contraction patterns are different in the recently described three types of achalasia identified by high-resolution manometry. Robust contraction of the longitudinal muscle in type II achalasia causes pan-esophageal pressurization and is the mechanism of whatever little esophageal emptying that take place in the absence of peristalsis and impaired LES relaxation. It may be that preserved longitudinal muscle contraction is also the reason for superior outcome to medical/surgical therapy in type II achalasia esophagus. Prolonged contractions of longitudinal muscles of the esophagus is a possible mechanism of heartburn and "angina like" pain seen in esophageal motility disorders and possibly achalasia esophagus. Novel techniques to record longitudinal muscle contraction are on the horizon. Neuro-pharmacologic control of circular and longitudinal muscles is different, which provides an important opportunity for the development of novel pharmacological therapies to treat sensory and motor disorders of the esophagus.

Ventricular fibrillation in an ambulatory patient supported by a left ventricular assist device: highlighting the ICD controversy.

Science.gov (United States)

Boilson, Barry A; Durham, Lucian A; Park, Soon J

2012-01-01

Left ventricular assist devices (LVADs) provide an effective means of managing advanced pump failure as a means of bridging to cardiac transplantation or as permanent therapy. Although ventricular arrhythmias remain common post-LVAD implantation, such therapy may allow malignant arrhythmias to be tolerated hemodynamically. This report describes the clinical findings in a patient who had likely been in a ventricular tachyarrhythmia for several days and presented in ventricular fibrillation, ambulatory, and mentating normally. This report, with previous similar reports, is additive to the body of evidence that LVADs alter the physiologic impact of ventricular arrhythmias in advanced heart failure and highlights the need for thoughtful programming of implantable cardioverter defibrillator therapies in these patients.

Action potential conduction between a ventricular cell model and an isolated ventricular cell

NARCIS (Netherlands)

Wilders, R.; Kumar, R.; Joyner, R. W.; Jongsma, H. J.; Verheijck, E. E.; Golod, D.; van Ginneken, A. C.; Goolsby, W. N.

1996-01-01

We used the Luo and Rudy (LR) mathematical model of the guinea pig ventricular cell coupled to experimentally recorded guinea pig ventricular cells to investigate the effects of geometrical asymmetry on action potential propagation. The overall correspondence of the LR cell model with the recorded

Upper airway muscles awake and asleep.

Science.gov (United States)

Sériès, Frédéric

2002-06-01

Upper airway (UA) structures are involved in different respiratory and non-respiratory tasks. The coordination of agonist and antagonist UA dilators is responsible for their mechanical function and their ability to maintain UA patency throughout the respiratory cycle. The activity of these muscles is linked with central respiratory activity but also depends on UA pressure changes and is greatly influenced by sleep. UA muscles are involved in determining UA resistance and stability (i.e. closing pressure), and the effect of sleep on these variables may be accounted for by its effect on tonic and phasic skeletal muscle activities. The mechanical effects of UA dilator contraction also depend on their physiological properties (capacity to generate tension in vitro, activity of the anaerobic enzymatic pathway, histo-chemical characteristics that may differ between subjects who may or may not have sleep-related obstructive breathing disorders). These characteristics may represent an adaptive process to an increased resistive loading of these muscles. The apparent discrepancy between the occurrence of UA closure and an increased capacity to generate tension in sleep apnea patients may be due to a reduction in the effectiveness of UA muscle contraction in these patients; such an increase in tissue stiffness could be accounted for by peri-muscular tissue characteristics. Therefore, understanding of UA muscle physiological characteristics should take into account its capacity for force production and its mechanical coupling with other UA tissues. Important research goals for the future will be to integrate these issues with other physiological features of the disease, such as UA size and dimension, histological characteristics of UA tissues and the effect of sleep on muscle function. Such integration will better inform understanding of the role of pharyngeal UA muscles in the pathophysiology of the sleep apnea/hypopnea syndrome.

Non-uniform muscle fat replacement along the proximodistal axis in Duchenne muscular dystrophy.

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Hooijmans, M T; Niks, E H; Burakiewicz, J; Anastasopoulos, C; van den Berg, S I; van Zwet, E; Webb, A G; Verschuuren, J J G M; Kan, H E

2017-05-01

The progressive replacement of muscle tissue by fat in Duchenne muscular dystrophy (DMD) has been studied using quantitative MRI between, but not within, individual muscles. We studied fat replacement along the proximodistal muscle axis using the Dixon technique on a 3T MR scanner in 22 DMD patients and 12 healthy controls. Mean fat fractions per muscle per slice for seven lower and upper leg muscles were compared between and within groups assuming a parabolic distribution. Average fat fraction for a small central slice stack and a large coverage slice stack were compared to the value when the stack was shifted one slice (15 mm) up or down. Higher fat fractions were observed in distal and proximal muscle segments compared to the muscle belly in all muscles of the DMD subjects (p muscle end regions are exposed to higher mechanical strain, which points towards mechanical disruption of the sarcolemma as one of the key factors in the pathophysiology. Overall, this non-uniformity in fat replacement needs to be taken into account to prevent sample bias when applying quantitative MRI as biomarker in clinical trials for DMD. Copyright © 2017 Elsevier B.V. All rights reserved.

A novel dynamic cardiac simulator utilizing pneumatic artificial muscle.

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Liu, Hao; Yan, Jie; Zhou, Yuanyuan; Li, Hongyi; Li, Changji

2013-01-01

With the development of methods and skills of minimally invasive surgeries, equipments for doctors' training and practicing are in high demands. Especially for the cardiovascular surgeries, operators are requested to be familiar with the surgical environment of a beating heart. In this paper, we present a new dynamic cardiac simulator utilizing pneumatic artificial muscle to realize heartbeat. It's an artificial left ventricular of which the inner chamber is made of thermoplastic elastomers (TPE) with an anatomical structure of the real human heart. It is covered by another layer of material forming the artificial muscle which actuates the systole and diastole uniformly and omnidirectionally as the cardiac muscle does. Preliminary experiments were conducted to evaluate the performance of the simulator. The results indicated that the pressure at the terminal of the aorta could be controlled within the range of normal human systolic pressure, which quantitatively validated the new actuating mode of the heart-beating is effective.

Anti-myostatin antibody increases muscle mass and strength and improves insulin sensitivity in old mice.

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Camporez, João-Paulo G; Petersen, Max C; Abudukadier, Abulizi; Moreira, Gabriela V; Jurczak, Michael J; Friedman, Glenn; Haqq, Christopher M; Petersen, Kitt Falk; Shulman, Gerald I

2016-02-23

Sarcopenia, or skeletal muscle atrophy, is a debilitating comorbidity of many physiological and pathophysiological processes, including normal aging. There are no approved therapies for sarcopenia, but the antihypertrophic myokine myostatin is a potential therapeutic target. Here, we show that treatment of young and old mice with an anti-myostatin antibody (ATA 842) for 4 wk increased muscle mass and muscle strength in both groups. Furthermore, ATA 842 treatment also increased insulin-stimulated whole body glucose metabolism in old mice, which could be attributed to increased insulin-stimulated skeletal muscle glucose uptake as measured by a hyperinsulinemic-euglycemic clamp. Taken together, these studies provide support for pharmacological inhibition of myostatin as a potential therapeutic approach for age-related sarcopenia and metabolic disease.

Skeletal Muscle-specific G Protein-coupled Receptor Kinase 2 Ablation Alters Isolated Skeletal Muscle Mechanics and Enhances Clenbuterol-stimulated Hypertrophy.

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Woodall, Benjamin P; Woodall, Meryl C; Luongo, Timothy S; Grisanti, Laurel A; Tilley, Douglas G; Elrod, John W; Koch, Walter J

2016-10-14

GRK2, a G protein-coupled receptor kinase, plays a critical role in cardiac physiology. Adrenergic receptors are the primary target for GRK2 activity in the heart; phosphorylation by GRK2 leads to desensitization of these receptors. As such, levels of GRK2 activity in the heart directly correlate with cardiac contractile function. Furthermore, increased expression of GRK2 after cardiac insult exacerbates injury and speeds progression to heart failure. Despite the importance of this kinase in both the physiology and pathophysiology of the heart, relatively little is known about the role of GRK2 in skeletal muscle function and disease. In this study we generated a novel skeletal muscle-specific GRK2 knock-out (KO) mouse (MLC-Cre:GRK2 fl/fl ) to gain a better understanding of the role of GRK2 in skeletal muscle physiology. In isolated muscle mechanics testing, GRK2 ablation caused a significant decrease in the specific force of contraction of the fast-twitch extensor digitorum longus muscle yet had no effect on the slow-twitch soleus muscle. Despite these effects in isolated muscle, exercise capacity was not altered in MLC-Cre:GRK2 fl/fl mice compared with wild-type controls. Skeletal muscle hypertrophy stimulated by clenbuterol, a β 2 -adrenergic receptor (β 2 AR) agonist, was significantly enhanced in MLC-Cre:GRK2 fl/fl mice; mechanistically, this seems to be due to increased clenbuterol-stimulated pro-hypertrophic Akt signaling in the GRK2 KO skeletal muscle. In summary, our study provides the first insights into the role of GRK2 in skeletal muscle physiology and points to a role for GRK2 as a modulator of contractile properties in skeletal muscle as well as β 2 AR-induced hypertrophy. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Skeletal Muscle-specific G Protein-coupled Receptor Kinase 2 Ablation Alters Isolated Skeletal Muscle Mechanics and Enhances Clenbuterol-stimulated Hypertrophy*

Science.gov (United States)

Woodall, Benjamin P.; Woodall, Meryl C.; Luongo, Timothy S.; Grisanti, Laurel A.; Tilley, Douglas G.; Elrod, John W.; Koch, Walter J.

2016-01-01

GRK2, a G protein-coupled receptor kinase, plays a critical role in cardiac physiology. Adrenergic receptors are the primary target for GRK2 activity in the heart; phosphorylation by GRK2 leads to desensitization of these receptors. As such, levels of GRK2 activity in the heart directly correlate with cardiac contractile function. Furthermore, increased expression of GRK2 after cardiac insult exacerbates injury and speeds progression to heart failure. Despite the importance of this kinase in both the physiology and pathophysiology of the heart, relatively little is known about the role of GRK2 in skeletal muscle function and disease. In this study we generated a novel skeletal muscle-specific GRK2 knock-out (KO) mouse (MLC-Cre:GRK2fl/fl) to gain a better understanding of the role of GRK2 in skeletal muscle physiology. In isolated muscle mechanics testing, GRK2 ablation caused a significant decrease in the specific force of contraction of the fast-twitch extensor digitorum longus muscle yet had no effect on the slow-twitch soleus muscle. Despite these effects in isolated muscle, exercise capacity was not altered in MLC-Cre:GRK2fl/fl mice compared with wild-type controls. Skeletal muscle hypertrophy stimulated by clenbuterol, a β2-adrenergic receptor (β2AR) agonist, was significantly enhanced in MLC-Cre:GRK2fl/fl mice; mechanistically, this seems to be due to increased clenbuterol-stimulated pro-hypertrophic Akt signaling in the GRK2 KO skeletal muscle. In summary, our study provides the first insights into the role of GRK2 in skeletal muscle physiology and points to a role for GRK2 as a modulator of contractile properties in skeletal muscle as well as β2AR-induced hypertrophy. PMID:27566547

Structural defects in cilia of the choroid plexus, subfornical organ and ventricular ependyma are associated with ventriculomegaly

Directory of Open Access Journals (Sweden)

Swiderski Ruth E

2012-10-01

Full Text Available Abstract Background Hydrocephalus is a heterogeneous disorder with multiple etiologies that are not yet fully understood. Animal models have implicated dysfunctional cilia of the ependyma and choroid plexus in the development of the disorder. In this report, we sought to determine the origin of the ventriculomegaly in four Bardet Biedl syndrome (BBS mutant mouse strains as models of a ciliopathy. Methods Evans Blue dye was injected into the lateral ventricle of wild- type and BBS mutant mice to determine whether obstruction of intra- or extra-ventricular CSF flow contributed to ventriculomegaly. Transmission electron microscopy (TEM was used to examine the ultrastructure of the choroid plexus, subfornical organ (SFO, subcommisural organ (SCO, and ventricular ependyma to evaluate their ultrastructure and the morphology of their primary and motile cilia. Results and discussion No obstruction of intra- or extra-ventricular CSF flow was observed, implying a communicating form of hydrocephalus in BBS mutant mice. TEM analyses of the mutants showed no evidence of choroidal papillomas or breakdown of the blood:CSF barrier. In contrast, structural defects were observed in a subpopulation of cilia lining the choroid plexus, SFO, and ventricular ependyma. These included disruptions of the microtubular structure of the axoneme and the presence of electron-dense vesicular-like material along the ciliary shaft and at the tips of cilia. Conclusions Abnormalities in cilia structure and function have the potential to influence ciliary intraflagellar transport (IFT, cilia maintenance, protein trafficking, and regulation of CSF production. Ciliary structural defects are the only consistent pathological features associated with CSF-related structures in BBS mutant mice. These defects are observed from an early age, and may contribute to the underlying pathophysiology of ventriculomegaly.

Epicardial mapping of ventricular fibrillation over the posterior descending artery and left posterior papillary muscle of the swine heart.

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Nielsen, Thomas D; Huang, Jian; Rogers, Jack M; Killingsworth, Cheryl R; Ideker, Raymond E

2009-01-01

Recent studies suggest that during ventricular fibrillation (VF) epicardial vessels may be a site of conduction block and the posterior papillary muscle (PPM) in the left ventricle (LV) may be the location of a "mother rotor." The goal of this study was to obtain evidence to support or refute these possibilities. Epicardial activation over the posterior LV and right ventricle (RV) was mapped during the first 20 s of electrically induced VF in six open-chest pigs with a 504 electrode plaque covering a 20 cm(2) area centered over the posterior descending artery (PDA). The locations of epicardial breakthrough as well as reentry clustered in time and space during VF. Spatially, reentry occurred significantly more frequently over the LV than the RV in all 48 episodes, and breakthrough clustered near the PPM (p < 0.001). Significant temporal clustering occurred in 79% of breakthrough episodes and 100% of reentry episodes. These temporal clusters occurred at different times so that there was significantly less breakthrough when reentry was present (p < 0.0001). Conduction block occurred significantly more frequently near the PDA than elsewhere. The PDA is a site of epicardial block which may contribute to VF maintenance. Epicardial breakthrough clusters near the PPM. Reentry also clusters in space but at a separate site. The fact that breakthrough and reentry cluster at different locations and at different times supports the possibility of a drifting filament at the PPM so that at times reentry is present on the surface but at other times the reentrant wavefront breaks through to the epicardium.

Sarcopenia in hiding: The risk and consequence of underestimating muscle dysfunction in nonalcoholic steatohepatitis.

Science.gov (United States)

Bhanji, Rahima A; Narayanan, Praveena; Allen, Alina M; Malhi, Harmeet; Watt, Kymberly D

2017-12-01

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. Up to one third of individuals with NAFLD will develop nonalcoholic steatohepatitis (NASH), which is associated with progression to cirrhosis and is rapidly becoming the leading indication for liver transplantation. Sarcopenia is defined as a progressive and generalized loss of skeletal muscle mass, strength, and function. It is observed in up to 60% of patients with end-stage liver disease and portends a poor prognosis. Recent studies have shown that sarcopenia is a novel risk factor for developing NAFLD. Pathophysiological mechanisms relating sarcopenia and NASH may include insulin resistance (IR) and increased inflammation. IR leads to accumulation of triglycerides in both muscle tissue and the liver. It also exacerbates proteolysis and leads to muscle depletion. Chronic inflammation leads to liver injury and progression of fibrosis. The inflammatory milieu also stimulates protein catabolism. Viewing skeletal muscle as an endocrine organ that secretes various salutary myokines may help us understand its role in the development of steatosis. A better understanding of the pathophysiology will aid in developing physical and pharmacological therapeutic interventions. In this review, we will explore the complex inter-relationships between sarcopenia and NASH. We will discuss the impact of sarcopenia in patients with NASH and therapeutic options for the management of sarcopenia. (Hepatology 2017;66:2055-2065). © 2017 by the American Association for the Study of Liver Diseases.

NO-sGC Pathway Modulates Ca2+ Release and Muscle Contraction in Zebrafish Skeletal Muscle.

Science.gov (United States)

Xiyuan, Zhou; Fink, Rainer H A; Mosqueira, Matias

2017-01-01

Vertebrate skeletal muscle contraction and relaxation is a complex process that depends on Ca 2+ ions to promote the interaction of actin and myosin. This process can be modulated by nitric oxide (NO), a gas molecule synthesized endogenously by (nitric oxide synthase) NOS isoforms. At nanomolar concentrations NO activates soluble guanylate cyclase (sGC), which in turn activates protein kinase G via conversion of GTP into cyclic GMP. Alternatively, NO post-translationally modifies proteins via S-nitrosylation of the thiol group of cysteine. However, the mechanisms of action of NO on Ca 2+ homeostasis during muscle contraction are not fully understood and we hypothesize that NO exerts its effects on Ca 2+ homeostasis in skeletal muscles mainly through negative modulation of Ca 2+ release and Ca 2+ uptake via the NO-sGC-PKG pathway. To address this, we used 5-7 days-post fecundation-larvae of zebrafish, a well-established animal model for physiological and pathophysiological muscle activity. We evaluated the response of muscle contraction and Ca 2+ transients in presence of SNAP, a NO-donor, or L-NAME, an unspecific NOS blocker in combination with specific blockers of key proteins of Ca 2+ homeostasis. We also evaluate the expression of NOS in combination with dihydropteridine receptor, ryanodine receptor and sarco/endoplasmic reticulum Ca 2+ ATPase. We concluded that endogenous NO reduced force production through negative modulation of Ca 2+ transients via the NO-sGC pathway. This effect could be reversed using an unspecific NOS blocker or sGC blocker.

Imaging Alzheimer's disease pathophysiology with PET

Directory of Open Access Journals (Sweden)

Lucas Porcello Schilling

Full Text Available ABSTRACT Alzheimer's disease (AD has been reconceptualised as a dynamic pathophysiological process characterized by preclinical, mild cognitive impairment (MCI, and dementia stages. Positron emission tomography (PET associated with various molecular imaging agents reveals numerous aspects of dementia pathophysiology, such as brain amyloidosis, tau accumulation, neuroreceptor changes, metabolism abnormalities and neuroinflammation in dementia patients. In the context of a growing shift toward presymptomatic early diagnosis and disease-modifying interventions, PET molecular imaging agents provide an unprecedented means of quantifying the AD pathophysiological process, monitoring disease progression, ascertaining whether therapies engage their respective brain molecular targets, as well as quantifying pharmacological responses. In the present study, we highlight the most important contributions of PET in describing brain molecular abnormalities in AD.

The helical ventricular myocardial band: global, three-dimensional, functional architecture of the ventricular myocardium.

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Kocica, Mladen J; Corno, Antonio F; Carreras-Costa, Francesc; Ballester-Rodes, Manel; Moghbel, Mark C; Cueva, Clotario N C; Lackovic, Vesna; Kanjuh, Vladimir I; Torrent-Guasp, Francisco

2006-04-01

We are currently witnessing the advent of new diagnostic tools and therapies for heart diseases, but, without serious scientific consensus on fundamental questions about normal and diseased heart structure and function. During the last decade, three successive, international, multidisciplinary symposia were organized in order to setup fundamental research principles, which would allow us to make a significant step forward in understanding heart structure and function. Helical ventricular myocardial band of Torrent-Guasp is the revolutionary new concept in understanding global, three-dimensional, functional architecture of the ventricular myocardium. This concept defines the principal, cumulative vectors, integrating the tissue architecture (i.e. form) and net forces developed (i.e. function) within the ventricular mass. Here we expose the compendium of Torrent-Guasp's half-century long functional anatomical investigations in the light of ongoing efforts to define the integrative approach, which would lead to new understanding of the ventricular form and function by linking across multiple scales of biological organization, as defined in ongoing Physiome project. Helical ventricular myocardial band of Torrent-Guasp may also, hopefully, allow overcoming some difficulties encountered in contemporary efforts to create a comprehensive mathematical model of the heart.

New and emerging biomarkers in left ventricular systolic dysfunction--insight into dilated cardiomyopathy.

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Gopal, Deepa M; Sam, Flora

2013-08-01

Dilated cardiomyopathy (DCM) is characterized by deteriorating cardiac performance, impaired contraction and dilation of the left ventricle (or both ventricles). Blood markers--known as "biomarkers"--allow insight into underlying pathophysiologic mechanisms and biologic pathways while predicting outcomes and guiding heart failure management and/or therapies. In this review, we provide an alternative approach to conceptualize heart failure biomarkers: the cardiomyocyte, its surrounding microenvironment, and the macroenvironment, integrating these entities which may impact cellular processes involved in the pathogenesis and/or propagation of DCM. Newer biomarkers of left ventricular systolic dysfunction can be categorized under: (a) myocyte stress and stretch, (b) myocyte apoptosis, (c) cardiac interstitium, (d) inflammation, (e) oxidative stress, (f) cardiac energetics, (g) neurohormones, and (h) renal biomarkers. Biomarkers provide insight into the pathogenesis of DCM while predicting and potentially providing prognostic information in these patients with heart failure.

Application of radionuclide ventriculography phase analysis in patients with atrial or ventricular pacing for detecting ventricular abnormal excitation

International Nuclear Information System (INIS)

Shi Rongfang; Wang Zhonggan; Li Shengting

1996-01-01

The aim of the study was to increase the accuracy of detecting ventricular abnormal excitation. During atrial or ventricular pacing, radionuclide ventriculography phase analysis (RNV-PA) was performed in 17 patients with Wolff-Parkinson-White (W-P-W) syndrome and paroxysmal supra ventricular tachycardia (PSVT) and ventricular tachycardia (PVT). During pacing, detection rate of abnormal excitation by RNV-PA was 95.5%, compared with 68.2% during basic conduction. Atrial or ventricular pacing can significantly increase the detection rate of abnormal excitation by RNV-PA in patients with W-P-W syndrome. It may be a valuable method for identifying the abnormal excitation and estimating the therapeutic effect of ablation

Discrete Pathophysiology is Uncommon in Patients with Nonspecific Arm Pain.

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Kortlever, Joost T P; Janssen, Stein J; Molleman, Jeroen; Hageman, Michiel G J S; Ring, David

2016-06-01

Nonspecific symptoms are common in all areas of medicine. Patients and caregivers can be frustrated when an illness cannot be reduced to a discrete pathophysiological process that corresponds with the symptoms. We therefore asked the following questions: 1) Which demographic factors and psychological comorbidities are associated with change from an initial diagnosis of nonspecific arm pain to eventual identification of discrete pathophysiology that corresponds with symptoms? 2) What is the percentage of patients eventually diagnosed with discrete pathophysiology, what are those pathologies, and do they account for the symptoms? We evaluated 634 patients with an isolated diagnosis of nonspecific upper extremity pain to see if discrete pathophysiology was diagnosed on subsequent visits to the same hand surgeon, a different hand surgeon, or any physician within our health system for the same pain. There were too few patients with discrete pathophysiology at follow-up to address the primary study question. Definite discrete pathophysiology that corresponded with the symptoms was identified in subsequent evaluations by the index surgeon in one patient (0.16% of all patients) and cured with surgery (nodular fasciitis). Subsequent doctors identified possible discrete pathophysiology in one patient and speculative pathophysiology in four patients and the index surgeon identified possible discrete pathophysiology in four patients, but the five discrete diagnoses accounted for only a fraction of the symptoms. Nonspecific diagnoses are not harmful. Prospective randomized research is merited to determine if nonspecific, descriptive diagnoses are better for patients than specific diagnoses that imply pathophysiology in the absence of discrete verifiable pathophysiology.

Tuberculosis 2: Pathophysiology and microbiology of pulmonary ...

African Journals Online (AJOL)

2005-08-01

Aug 1, 2005 ... February 2013 Downloaded from www.southsudanmedicaljournal.com. MaIN arTIClES. 10. Tuberculosis 2: Pathophysiology and microbiology of pulmonary tuberculosis. Robert L. Serafino Wania MBBS, MrCP, MSc (Trop Med). Pathophysiology. Inhalation of Mycobacterium tuberculosis leads to one of.

Pathophysiology of cervical myelopathy.

Science.gov (United States)

Baptiste, Darryl C; Fehlings, Michael G

2006-01-01

Cervical myelopathy is a group of closely related disorders usually caused by spondylosis or by ossification of the posterior longitudinal ligament and is characterized by compression of the cervical spinal cord or nerve roots by varying degrees and number of levels. The decrease in diameter of the vertebral canal secondary to disc degeneration and osteophytic spurs compresses the spinal cord and nerve roots at one or several levels, producing direct damage and often secondary ischemic changes. Clinicians who treat cervical myelopathy cord injuries should have a basic understanding of the pathophysiology and the processes that are initiated after the spinal cord has been injured. Literature review. Literature review of human cervical myelopathy and clinically relevant animal models to further our understanding of the pathological mechanisms involved. The pathophysiology of cervical myelopathy involves static factors, which result in acquired or developmental stenosis of the cervical canal and dynamic factors, which involve repetitive injury to the cervical cord. These mechanical factors in turn result in direct injury to neurons and glia as well as a secondary cascade of events including ischemia, excitotoxicity, and apoptosis; a pathobiology similar to that occurring in traumatic spinal cord injury. This review summarizes some of the significant pathophysiological processes involved in cervical myelopathy.

Primary skeletal muscle myoblasts from chronic heart failure patients exhibit loss of anti-inflammatory and proliferative activity

NARCIS (Netherlands)

Sente, T.; Berendoncks, A.M. Van; Jonckheere, A.I.; Rodenburg, R.J.T.; Lauwers, P.; Hoof, V. Van; Wouters, A.; Lardon, F.; Hoymans, V.Y.; Vrints, C.J.

2016-01-01

BACKGROUND: Peripheral skeletal muscle wasting is a common finding with adverse effects in chronic heart failure (HF). Whereas its clinical relevance is beyond doubt, the underlying pathophysiological mechanisms are not yet fully elucidated. We aimed to introduce and characterize the primary culture

Effect of right ventricular electrode location (outflow tract vs. apex) on mechanical Ventricular synchrony in patients that underwent pacemaker implant therapy

International Nuclear Information System (INIS)

Rincon, Oscar S; Saenz, Luis C; Salazar, Gabriel; Hernandez, Edgar

2008-01-01

Objective: to assess in depth the effect of ventricular stimulation from the right ventricular outflow tract and the apex on mechanical ventricular synchrony. Materials And Methods: cohort analytical study. 20 patients with indication of definitive pacemaker indication underwent trans thoracic echocardiogram before and after pacemaker implant with electrode implantation in the right ventricular outflow tract and in the apex (10 patients in each group). There was no structural cardiopathy, ejection fraction was ? 50%, QRS and AV conduction were normal. Mechanical ventricular asynchrony (M mode and tissue doppler) and implant and device parameters were evaluated. Statistical Analysis: results are given as mean values, standard deviation or percentages.Continuous variables were compared using Chi-square test and ANOVA. A p <0.05 value was considered statistically significant. Results: in five patients (25%) a pre-implant ventricular asynchrony was found; in seven (70%) ventricular asynchrony post-implant in the right ventricle outflow tract and in 5 (50%) in the apex. Mean interventricular pot-implant delay was 21,6 ms in the right ventricular outflow tract and 11,5 ms in the apex (p = 0,8); mean septal to lateral wall delay was 73 ms in the right ventricular outflow tract and 26 ms in the apex (p = 0,8). QRS post-implant delay was 134 ms in the right ventricular outflow tract and 140 ms in the apex (p = 0,1). No differences between implant parameters and device programming were found. Conclusions: presence of ventricular asynchrony was evidenced in patients with normal QRS and structurally healthy heart. Ventricular stimulation with pacemaker from the apex or the right ventricular outflow tract suggests acute ventricular asynchrony at least in 60% of the cases, without statistically significant difference between both groups.

Statin-associated muscle symptoms: impact on statin therapy-European Atherosclerosis Society Consensus Panel Statement on Assessment, Aetiology and Management

NARCIS (Netherlands)

Stroes, Erik S.; Thompson, Paul D.; Corsini, Alberto; Vladutiu, Georgirene D.; Raal, Frederick J.; Ray, Kausik K.; Roden, Michael; Stein, Evan; Tokgözoğlu, Lale; Nordestgaard, Børge G.; Bruckert, Eric; de Backer, Guy; Krauss, Ronald M.; Laufs, Ulrich; Santos, Raul D.; Hegele, Robert A.; Hovingh, G. Kees; Leiter, Lawrence A.; Mach, Francois; März, Winfried; Newman, Connie B.; Wiklund, Olov; Jacobson, Terry A.; Catapano, Alberico L.; Chapman, M. John; Ginsberg, Henry N.; Leiter, Lawrence

2015-01-01

Statin-associated muscle symptoms (SAMS) are one of the principal reasons for statin non-adherence and/or discontinuation, contributing to adverse cardiovascular outcomes. This European Atherosclerosis Society (EAS) Consensus Panel overviews current understanding of the pathophysiology of

Self-organization of muscle cell structure and function.

Directory of Open Access Journals (Sweden)

Anna Grosberg

2011-02-01

Full Text Available The organization of muscle is the product of functional adaptation over several length scales spanning from the sarcomere to the muscle bundle. One possible strategy for solving this multiscale coupling problem is to physically constrain the muscle cells in microenvironments that potentiate the organization of their intracellular space. We hypothesized that boundary conditions in the extracellular space potentiate the organization of cytoskeletal scaffolds for directed sarcomeregenesis. We developed a quantitative model of how the cytoskeleton of neonatal rat ventricular myocytes organizes with respect to geometric cues in the extracellular matrix. Numerical results and in vitro assays to control myocyte shape indicated that distinct cytoskeletal architectures arise from two temporally-ordered, organizational processes: the interaction between actin fibers, premyofibrils and focal adhesions, as well as cooperative alignment and parallel bundling of nascent myofibrils. Our results suggest that a hierarchy of mechanisms regulate the self-organization of the contractile cytoskeleton and that a positive feedback loop is responsible for initiating the break in symmetry, potentiated by extracellular boundary conditions, is required to polarize the contractile cytoskeleton.

Self-organization of muscle cell structure and function.

Science.gov (United States)

Grosberg, Anna; Kuo, Po-Ling; Guo, Chin-Lin; Geisse, Nicholas A; Bray, Mark-Anthony; Adams, William J; Sheehy, Sean P; Parker, Kevin Kit

2011-02-01

The organization of muscle is the product of functional adaptation over several length scales spanning from the sarcomere to the muscle bundle. One possible strategy for solving this multiscale coupling problem is to physically constrain the muscle cells in microenvironments that potentiate the organization of their intracellular space. We hypothesized that boundary conditions in the extracellular space potentiate the organization of cytoskeletal scaffolds for directed sarcomeregenesis. We developed a quantitative model of how the cytoskeleton of neonatal rat ventricular myocytes organizes with respect to geometric cues in the extracellular matrix. Numerical results and in vitro assays to control myocyte shape indicated that distinct cytoskeletal architectures arise from two temporally-ordered, organizational processes: the interaction between actin fibers, premyofibrils and focal adhesions, as well as cooperative alignment and parallel bundling of nascent myofibrils. Our results suggest that a hierarchy of mechanisms regulate the self-organization of the contractile cytoskeleton and that a positive feedback loop is responsible for initiating the break in symmetry, potentiated by extracellular boundary conditions, is required to polarize the contractile cytoskeleton.

Transforming pathophysiology instruction through narrative pedagogy and Socratic questioning.

Science.gov (United States)

Rogge, M M

2001-01-01

Pathophysiology, heavily content driven, has typically been taught through the use of traditional behavioral pedagogy and a reliance on the formal lecture. The author describes the limitations of this approach to teaching pathophysiology and describes the use of narrative pedagogy and Socratic questioning as alternative methods of instruction to augment lecture methods. Specific strategies for transforming traditional classroom teaching by using Socratic questions in a pathophysiology course for nurse practitioners are described. Student and faculty reactions to the initial efforts to transform pathophysiology instruction are also described.

Myostatin from the heart: local and systemic actions in cardiac failure and muscle wasting

Science.gov (United States)

Breitbart, Astrid; Auger-Messier, Mannix; Molkentin, Jeffery D.

2011-01-01

A significant proportion of heart failure patients develop skeletal muscle wasting and cardiac cachexia, which is associated with a very poor prognosis. Recently, myostatin, a cytokine from the transforming growth factor-β (TGF-β) family and a known strong inhibitor of skeletal muscle growth, has been identified as a direct mediator of skeletal muscle atrophy in mice with heart failure. Myostatin is mainly expressed in skeletal muscle, although basal expression is also detectable in heart and adipose tissue. During pathological loading of the heart, the myocardium produces and secretes myostatin into the circulation where it inhibits skeletal muscle growth. Thus, genetic elimination of myostatin from the heart reduces skeletal muscle atrophy in mice with heart failure, whereas transgenic overexpression of myostatin in the heart is capable of inducing muscle wasting. In addition to its endocrine action on skeletal muscle, cardiac myostatin production also modestly inhibits cardiomyocyte growth under certain circumstances, as well as induces cardiac fibrosis and alterations in ventricular function. Interestingly, heart failure patients show elevated myostatin levels in their serum. To therapeutically influence skeletal muscle wasting, direct inhibition of myostatin was shown to positively impact skeletal muscle mass in heart failure, suggesting a promising strategy for the treatment of cardiac cachexia in the future. PMID:21421824

Ventricular Effective Refraction Period and Ventricular Repolarization Analysis in Experimental Tachycardiomyopathy in Swine.

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Noszczyk-Nowak, Agnieszka; Pasławska, Urszula; Gajek, Jacek; Janiszewski, Adrian; Pasławski, Robert; Zyśko, Dorota; Nicpoń, Józef

2016-01-01

Swine are recognized animal models of human cardiovascular diseases. However, little is known on the CHF-associated changes in the electrophysiological ventricular parameters of humans and animals. The aim of this study was to analyze changes in the durations of ventricular effective refraction period (VERP), QT and QTc intervals of pigs with chronic tachycardia-induced tachycardiomyopathy (TIC). The study was comprised of 28 adult pigs (8 females and 20 males) of the Polish Large White breed. A one-chamber pacemaker was implanted in each of the 28 pigs. Electrocardiographic, echocardiographic and electrophysiological studies were carried out prior to the pacemaker implantation and at subsequent 4-week intervals. All electrocardiographic, echocardiographic and short electrophysiological study measurements in all swine were done under general anesthesia (propofol) after premedication with midazolam, medetomidine, and ketamine. No significant changes in the duration of QT interval and corrected QT interval (QTc) were observed during consecutive weeks of the experiment. The duration of the QTc interval of female pigs was shown to be significantly longer than that of the males throughout the whole study period. Beginning from the 12th week of rapid ventricular pacing, a significant increase in duration of VERP was observed in both male and female pigs. Males and females did not differ significantly in terms of VERP duration determined throughout the whole study period. Ventricular pacing, stimulation with 2 and 3 premature impulses at progressively shorter coupling intervals and an imposed rhythm of 130 bpm or 150 bpm induced transient ventricular tachycardia in one female pig and four male pigs. One episode of permanent ventricular tachycardia was observed. The number of induced arrhythmias increased proportionally to the severity of heart failure and duration of the experiment. However, relatively aggressive protocols of stimulation were required in order to induce

Ventricular arrhythmias in Chagas disease

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Marco Paulo Tomaz Barbosa

2015-02-01

Full Text Available Sudden death is one of the most characteristic phenomena of Chagas disease, and approximately one-third of infected patients develop life-threatening heart disease, including malignant ventricular arrhythmias. Fibrotic lesions secondary to chronic cardiomyopathy produce arrhythmogenic substrates that lead to the appearance and maintenance of ventricular arrhythmias. The objective of this study is to discuss the main clinical and epidemiological aspects of ventricular arrhythmias in Chagas disease, the specific workups and treatments for these abnormalities, and the breakthroughs needed to determine a more effective approach to these arrhythmias. A literature review was performed via a search of the PubMed database from 1965 to May 31, 2014 for studies of patients with Chagas disease. Clinical management of patients with chronic Chagas disease begins with proper clinical stratification and the identification of individuals at a higher risk of sudden cardiac death. Once a patient develops malignant ventricular arrhythmia, the therapeutic approach aims to prevent the recurrence of arrhythmias and sudden cardiac death by the use of implantable cardioverter defibrillators, antiarrhythmic drugs, or both. In select cases, invasive ablation of the reentrant circuit causing tachycardia may be useful. Ventricular arrhythmias are important manifestations of Chagas cardiomyopathy. This review highlights the absence of high-quality evidence regarding the treatment of ventricular arrhythmias in Chagas disease. Recognizing high-risk patients who require specific therapies, especially invasive procedures such as the implantation of cardioverter defibrillators and ablative approaches, is a major challenge in clinical practice.

The Histological Effects of L-arginine on Ventricular Myocardium in Iron Treated Male Rats

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M Sofiabadi

2012-05-01

Full Text Available

Background and Objectives: Iron overload is detrimental for the body and can create damage to different body tissues, such as myocardium by producing oxidative stress. Therefore, the antioxidant factors can neutralize iron induced damages. According to available reports, L-arginine as a precursor nitric oxide production has antioxidant effects. This study was carried out to evaluate the histological effects of iron overload on ventricular muscle and preventive role of L-arginine in male rats.

Methods: In this experiment, 40 male rats with weight range of 300-250g were divided at random into five equal groups including:1- Control, 2- Iron (10mg/kg, ip, 3- Iron(10mg/kg, ip+L-arginine (1mg/ml, po, 4- Iron (50mg/kg, ip and 5- Iron (50mg/kg,ip+L-arginine(1mg/ml,po. After treatment (6 weeks, the animals were anesthetized and the samples of left apical ventricular myocardium were taken out and morphological studies were done following fixation with 10% formalin and H&E staining. Microscopic parameters under study were cell swelling, vessel dilatation and hypercongestion, cell necrosis and tissue deformity. The type and severity of damage to the tissue were also noted. Data were analyzed using chi-square statistical procedure, and Pvalue≤0.05 were considered to be significant. 

Results: The data showed moderate changes in the ventricular myocardium of group 2 that was significant in comparison to the control group (P<0.05. The ventricular myocardium of group 3 showed low changes and wasn't significant in comparison to control group (P=0.84. The ventricular myocardium of the group 4 showed severe changes in comparison to the control group (P<0.01. The low change showed in the ventricular myocardium of group 5 that wasn't significant in comparison to the control group.

Conclusion: This study showed

Evaluation of Right Ventricular Function with Radionuclide Cardiac Angiography - Right Ventricular Ejection Fraction in Chronic Obstructive Lung Disease

International Nuclear Information System (INIS)

Sohn, In; Shin, Sung Hae; Chung, June Key; Lee, Myung Chul; Cho, Bo Youn; Lee, Young Woo; Han, Yong Cheol; Koh, Chang Soon

1982-01-01

To evaluate the usefulness of radionuclide cardiac angiography in the assessment of the right ventricular function, we measured right ventricular ejection fraction (RVEF) using single pass method. In 12 normal persons, RVEF averaged 52.7±5.9% (mean±S.D.). In 25 patients with chronic obstructive lung disease, RVEF was 37.2±10.6% and significantly lower than that of normal person (p<0.01). All 10 patients with right ventricular failure had abnormal RVEF, which was significantly lower than that of 14 persons without right ventricular failure (27.6±5.7%, 43.9±8.5%, respectively, p<0.01). It concluded that RVEF measured by single pass radionuclide cardiac angiography was a useful, noninvasive method to assess right ventricular function.

Evaluating the roles of detailed endocardial structures on right ventricular haemodynamics by means of CFD simulations.

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Sacco, Federica; Paun, Bruno; Lehmkuhl, Oriol; Iles, Tinen L; Iaizzo, Paul A; Houzeaux, Guillaume; Vázquez, Mariano; Butakoff, Constantine; Aguado-Sierra, Jazmin

2018-06-11

Computational modelling plays an important role in right ventricular (RV) haemodynamic analysis. However, current approaches employ smoothed ventricular anatomies. The aim of this study is to characterise RV haemodynamics including detailed endocardial structures like trabeculae, moderator band and papillary muscles (PMs). Four paired detailed and smoothed RV endocardium models (two male and two female) were reconstructed from ex-vivo human hearts high-resolution magnetic resonance images (MRI). Detailed models include structures with ≥1 mm 2 cross-sectional area. Haemodynamic characterisation was done by computational fluid dynamics (CFD) simulations with steady and transient inflows, using high performance computing (HPC). The differences between the flows in smoothed and detailed models were assessed using Q-criterion for vorticity quantification, the pressure drop between inlet and outlet, and the wall shear stress (WSS). Results demonstrated that detailed endocardial structures increase the degree of intra-ventricular pressure drop, decrease the WSS and disrupt the dominant vortex creating secondary small vortices. Increasingly turbulent blood flow was observed in the detailed RVs. Female RVs were less trabeculated and presented lower pressure drops than the males. In conclusion, neglecting endocardial structures in RV haemodynamic models may lead to inaccurate conclusions about the pressures, stresses, and blood flow behaviour in the cavity. This article is protected by copyright. All rights reserved.

Detection of left ventricular thrombi by computerised tomography

International Nuclear Information System (INIS)

Nair, C.K.; Sketch, M.H.; Mahoney, P.D.; Lynch, J.D.; Mooss, A.N.; Kenney, N.P.

1981-01-01

Sixteen patients suspected of having left ventricular mural thrombi were studied. All had suffered transmural myocardial infarction. Fifteen patients had a ventricular aneurysm. One had had systemic emboli. The mean length of time between the myocardial infarction and the study was 14.8 months, with a range of one month to 79 months. All patients underwent computerised tomography of the heart, M-mode echocardiography (M-mode), and two-dimensional echocardiography (2-D). Eight patients underwent left ventricular cineangiography. Five patients had surgical confirmation. Computerised tomography, two-dimensional, and M-mode echocardiography predicted left ventricular mural thrombi in 10, eight, and one of the 16 patients, respectively. Left ventricular cineangiography predicted left ventricular mural thrombi in four out of eight patients. Computerised tomography and left ventricular cineangiography correctly predicted the presence or absence of left ventricular thrombi in all five patients who underwent operation. In the same group, however, two-dimensional and M-mode echocardiography failed to predict the presence of thrombi in one and three patients, respectively. Among the 11 patients without surgical confirmation, one, in whom no left ventricular thrombi were shown by M-mode and two-dimensional echocardiography, was found to have thrombi on computerised tomography. In another, two-dimensional echocardiography was positive but this finding was not confirmed either by computerised tomography or by left ventricular angiography. (author)

Ventricular septal necrosis after blunt chest trauma

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Alireza Ahmadi

2012-07-01

Full Text Available Ventricular Septal Defect (VSD after blunt chest trauma is a very rare traumatic affection.We report here a case of blunt chest injury-related VSD and pseudoaneurysm.A 30-year old male truck driver was referred from a trauma center to our hospital seven days after a blunt chest trauma and rib fracture. The patient had severe pulmonary edemaand echocardiography showed large VSD. Several mechanisms are involved in the pathogenesis of this affection including an acute compression of the heart muscle between the sternum and the spine, leading to excessive changes in the intrathoracic and most likely theintracardiac pressure after blunt chest injury. Traumatical patients with the same symptoms may be at risk of sudden death. Therefore, a high grade of suspicion is mandatory even without solid evidence of myocardial damage on the initial evaluation. In continue somehidden angles of this case was discussed. Given the prognostic implications of traumatic VSD with associated pseudoaneurysm, its detection has critical value for preventing its clinicalsequelae.

Arrhythmogenic right ventricular dysplasia

International Nuclear Information System (INIS)

Vignolo Puglia, W.; Freire Colla, D.; Rivara Urrutia, D.; Lujambio Grene, M.; Arbiza Bruno, T.; Oliveira, G.; Cobas Rodriguez, J.

1997-01-01

The arrhythmogenic right ventricular dysplasia is a condition predominantly well defined with arrhythmic events. We analyze three cases diagnosed by the group. These cases were presented as ventricular tachycardia with a morphology of left bundle branch block, presenting one of them aborted sudden death in evolution. The baseline electrocardiogram and signal averaging were abnormal in two of the three cases, like the echocardiogram. The electrophysiological study was able to induce in the three patients with sustained monomorphic ventricular tachycardia morphology of left bundle branch block. The definitive diagnosis was made by right ventriculography in two cases and magnetic resonance imaging in the other. Treatment included antiarrhythmic drugs in the three cases and the placement of an automatic defibrillator which survived a sudden death (Author)

Longitudinal muscle of the esophagus: its role in esophageal health and disease.

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Mittal, Ravinder K

2013-07-01

The muscularis propria of the esophagus is organized into circular and longitudinal muscle layers. The function of the longitudinal muscle and its role in bolus propulsion are not clear. The goal of this review is to summarize what is known of the role of the longitudinal muscle in health, as well as in sensory and motor disorders of the esophagus. Simultaneous manometry and ultrasound imaging reveal that, during peristalsis, the two muscle layers of the esophagus contract in perfect synchrony. On the contrary, during transient lower esophageal sphincter (LES) relaxation, longitudinal muscle contracts independent of the circular muscle. Recent studies have provided novel insights into the role of the longitudinal muscle in LES relaxation and descending relaxation of the esophagus. In certain diseases (e.g. some motility disorders of the esophagus), there is discoordination between the two muscle layers, which likely plays an important role in the genesis of dysphagia and delayed esophageal emptying. There is close temporal correlation between prolonged contractions of the longitudinal muscles of the esophagus and esophageal 'angina-like' pain. Novel techniques to record longitudinal muscle contraction are reviewed. Longitudinal muscles of the esophagus play a key role in the physiology and pathophysiology of esophageal sensory and motor function. Neuro-pharmacologic controls of circular and longitudinal muscle are different, which provides an opportunity for the development of novel pharmacological therapies in the treatment of esophageal sensory and motor disorders.

Muscle mitochondrial metabolism and calcium signaling impairment in patients treated with statins

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Sirvent, P., E-mail: pascal.sirvent@univ-bpclermont.fr [U1046, INSERM, Université Montpellier 1 and Université Montpellier 2, 34295 Montpellier (France); CHRU Montpellier, 34295 Montpellier (France); Clermont Université, Université Blaise Pascal, EA 3533, Laboratoire des Adaptations Métaboliques à l' Exercice en conditions Physiologiques et Pathologiques (AME2P), BP 80026, F-63171 Aubière cedex (France); Fabre, O.; Bordenave, S. [U1046, INSERM, Université Montpellier 1 and Université Montpellier 2, 34295 Montpellier (France); CHRU Montpellier, 34295 Montpellier (France); Hillaire-Buys, D. [CHRU Montpellier, 34295 Montpellier (France); Raynaud De Mauverger, E.; Lacampagne, A.; Mercier, J. [U1046, INSERM, Université Montpellier 1 and Université Montpellier 2, 34295 Montpellier (France); CHRU Montpellier, 34295 Montpellier (France)

2012-03-01

The most common and problematic side effect of statins is myopathy. To date, the patho-physiological mechanisms of statin myotoxicity are still not clearly understood. In previous studies, we showed that acute application in vitro of simvastatin caused impairment of mitochondrial function and dysfunction of calcium homeostasis in human and rat healthy muscle samples. We thus evaluated in the present study, mitochondrial function and calcium signaling in muscles of patients treated with statins, who present or not muscle symptoms, by oxygraphy and recording of calcium sparks, respectively. Patients treated with statins showed impairment of mitochondrial respiration that involved mainly the complex I of the respiratory chain and altered frequency and amplitude of calcium sparks. The muscle problems observed in statin-treated patients appear thus to be related to impairment of mitochondrial function and muscle calcium homeostasis, confirming the results we previously reported in vitro. -- Highlights: ► The most common and problematic side effect of statins is myopathy. ► Patients treated with statins showed impairment of mitochondrial respiration. ► Statins-treated patients showed altered frequency and amplitude of calcium sparks.

Muscle mitochondrial metabolism and calcium signaling impairment in patients treated with statins

International Nuclear Information System (INIS)

Sirvent, P.; Fabre, O.; Bordenave, S.; Hillaire-Buys, D.; Raynaud De Mauverger, E.; Lacampagne, A.; Mercier, J.

2012-01-01

The most common and problematic side effect of statins is myopathy. To date, the patho-physiological mechanisms of statin myotoxicity are still not clearly understood. In previous studies, we showed that acute application in vitro of simvastatin caused impairment of mitochondrial function and dysfunction of calcium homeostasis in human and rat healthy muscle samples. We thus evaluated in the present study, mitochondrial function and calcium signaling in muscles of patients treated with statins, who present or not muscle symptoms, by oxygraphy and recording of calcium sparks, respectively. Patients treated with statins showed impairment of mitochondrial respiration that involved mainly the complex I of the respiratory chain and altered frequency and amplitude of calcium sparks. The muscle problems observed in statin-treated patients appear thus to be related to impairment of mitochondrial function and muscle calcium homeostasis, confirming the results we previously reported in vitro. -- Highlights: ► The most common and problematic side effect of statins is myopathy. ► Patients treated with statins showed impairment of mitochondrial respiration. ► Statins-treated patients showed altered frequency and amplitude of calcium sparks.

An update on pancreatic pathophysiology (do we have to rewrite pancreatic pathophysiology?).

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Hammer, Heinz F

2014-02-01

This review focuses on seven aspects of physiology and pathophysiology of the exocrine pancreas that have been intensively discussed and studied within the past few years: (1) the role of neurohormonal mechanisms like melatonin, leptin, or ghrelin in the stimulation of pancreatic enzyme secretion; (2) the initiation processes of acute pancreatitis, like fusion of zymogen granules with lysosomes leading to intracellular activation of trypsinogen by the lysosomal enzyme cathepsin B, or autoactivation of trypsinogen; (3) the role of genes in the pathogenesis of acute pancreatitis; (4) the role of alcohol and constituents of alcoholic beverages in the pathogenesis of acute pancreatitis; (5) the role of pancreatic hypertension, neuropathy, and central mechanisms for the pathogenesis of pain in chronic pancreatitis; (6) the relation between exocrine pancreatic function and diabetes mellitus; and (7) pathophysiology, diagnosis and treatment of pancreatic steatorrhea.

Isolated left ventricular non-compaction cardiomyopathy associated with polymorphous ventricular tachycardia mimicking torsades de pointes

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Oana Dickinson

2013-02-01

Full Text Available Left ventricular non-compaction (LVNC cardiomyopathy is a rare congenital disorder, classified by the American Heart Association as a primary genetic cardiomyopathy and characterized by multiple trabeculations within the left ventricle. LVNC cardiomyopathy has been associated with 3 major clinical manifestations: heart failure, atrial and ventricular arrhythmias and thromboembolic events, including stroke. In this case report, we describe a female patient with apparently isolated LVNC in whom pause-dependent polymorphic ventricular tachycardia suggesting torsades de pointes occurred in the presence of a normal QT interval.

Two-dimensional echocardiographic features of right ventricular infarction

International Nuclear Information System (INIS)

D'Arcy, B.; Nanda, N.C.

1982-01-01

Real-time, two-dimensional echocardiographic studies were performed in 10 patients with acute myocardial infarction who had clinical features suggestive of right ventricular involvement. All patients showed right ventricular wall motion abnormalities. In the four-chamber view, seven patients showed akinesis of the entire right ventricular diaphragmatic wall and three showed akinesis of segments of the diaphragmatic wall. Segmental dyskinetic areas involving the right ventricular free wall were identified in four patients. One patient showed a large right ventricular apical aneurysm. Other echocardiographic features included enlargement of the right ventricle in eight cases, paradoxical ventricular septal motion in seven cases, tricuspid incompetence in eight cases, dilation of the stomach in four cases and localized pericardial effusion in two cases. Right ventricular infarction was confirmed by radionuclide methods in seven patients, at surgery in one patient and at autopsy in two patients

Major vault protein in cardiac and smooth muscle.

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Shults, Nataliia V; Das, Dividutta; Suzuki, Yuichiro J

Major vault protein (MVP) is the major component of the vault particle whose functions are not well understood. One proposed function of the vault is to serve as a mechanism of drug transport, which confers drug resistance in cancer cells. We show that MVP can be found in cardiac and smooth muscle. In human airway smooth muscle cells, knocking down MVP was found to cause cell death, suggesting that MVP serves as a cell survival factor. Further, our laboratory found that MVP is S-glutathionylated in response to ligand/receptor-mediated cell signaling. The S-glutathionylation of MVP appears to regulate protein-protein interactions between MVP and a protein called myosin heavy chain 9 (MYH9). Through MYH9 and Vsp34, MVP may form a complex with Beclin-1 that regulates autophagic cell death. In pulmonary vascular smooth muscle, proteasome inhibition promotes the ubiquitination of MVP, which may function as a mechanism of proteasome inhibition-mediated cell death. Investigating the functions and the regulatory mechanisms of MVP and vault particles is an exciting new area of research in cardiovascular/pulmonary pathophysiology.

The Role of Levosimendan in Patients with Decreased Left Ventricular Function Undergoing Cardiac Surgery

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Marija Bozhinovska

2016-06-01

Full Text Available The postoperative low cardiac output is one of the most important complications following cardiac surgery and is associated with increased morbidity and mortality. The condition requires inotropic support to achieve adequate hemodynamic status and tissue perfusion. While catecholamines are utilised as a standard therapy in cardiac surgery, their use is limited due to increased oxygen consumption. Levosimendan is calcium sensitising inodilatator expressing positive inotropic effect by binding with cardiac troponin C without increasing oxygen demand. Furthermore, the drug opens potassium ATP (KATP channels in cardiac mitochondria and in the vascular muscle cells, showing cardioprotective and vasodilator properties, respectively. In the past decade, levosimendan demonstrated promising results in treating patients with reduced left ventricular function when administered in peri- or post- operative settings. In addition, pre-operative use of levosimendan in patients with severely reduced left ventricular ejection fraction may reduce the requirements for postoperative inotropic support, mechanical support, duration of intensive care unit stay as well as hospital stay and a decrease in post-operative mortality. However, larger studies are needed to clarify clinical advantages of levosimendan versus conventional inotropes.

Atrial and ventricular function after cardioversion of atrial fibrillation.

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Xiong, C.; Sonnhag, C.; Nylander, E.; Wranne, B.

1995-01-01

OBJECTIVE--Previous studies on atrial recovery after cardioversion of atrial fibrillation have not taken into account new knowledge about the pathophysiology of transmitral and transtricuspid flow velocity patterns. It is possible to shed further light on this problem if atrioventricular inflow velocity, venous filling pattern, and atrioventricular annulus motion are recorded and interpreted together. DESIGN--Prospective examinations of mitral and tricuspid transvalvar flow velocities, superior caval and pulmonary venous filling, and mitral and tricuspid annulus motion were recorded using Doppler echocardiography. Examinations were performed before and 24 hours, 1 month, and 20 months after cardioversion. SETTING--Tertiary referral centre for cardiac disease with facilities for invasive and non-invasive investigation. PATIENTS--16 patients undergoing cardioversion of atrial fibrillation in whom sinus rhythm had persisted for 24 hours or more. RESULTS--Before conversion there was no identifiable A wave in transvalvar flow recordings. The total motion of the tricuspid and mitral annulus was subnormal and there was no identifiable atrial component. Venous flow patterns in general showed a low systolic velocity. After conversion, A waves and atrial components were seen in all patients and increased significantly (P atrial components, an increased systolic component of venous inflow, an increased A wave velocity, and a decreased E/A ratio of the transvalvar velocity curves. The ventricular component of annulus motion was unchanged. Changes in general occurred earlier on the right side than the left. CONCLUSIONS--This study indicates that, in addition to the previously known electromechanical dissociation of atrial recovery that exists after cardioversion of atrial fibrillation, there may also be a transient deterioration of ventricular function modulating the transvalvar inflow velocity recordings. Function on the right side generally becomes normal earlier than on the

Pattern Differences of Small Hand Muscle Atrophy in Amyotrophic Lateral Sclerosis and Mimic Disorders.

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Fang, Jia; Liu, Ming-Sheng; Guan, Yu-Zhou; Du, Hua; Li, Ben-Hong; Cui, Bo; Ding, Qing-Yun; Cui, Li-Ying

2016-04-05

Amyotrophic lateral sclerosis (ALS) and some mimic disorders, such as distal-type cervical spondylotic amyotrophy (CSA), Hirayama disease (HD), and spinobulbar muscular atrophy (SBMA) may present with intrinsic hand muscle atrophy. This study aimed to investigate different patterns of small hand muscle involvement in ALS and some mimic disorders. We compared the abductor digiti minimi/abductor pollicis brevis (ADM/APB) compound muscle action potential (CMAP) ratios between 200 ALS patients, 95 patients with distal-type CSA, 88 HD patients, 43 SBMA patients, and 150 normal controls. The ADM/APB CMAP amplitude ratio was significantly higher in the ALS patients (P mimic disorders presumably reflect distinct pathophysiological mechanisms underlying different disorders, and may aid in distinguishing between ALS and mimic disorders.

New and Emerging Biomarkers in Left Ventricular Systolic Dysfunction - Insight into Dilated Cardiomyopathy

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Gopal, Deepa M.; Sam, Flora

2013-01-01

Background Dilated cardiomyopathy (DCM) is characterized by deteriorating cardiac performance and impaired contraction and dilation of the left (or both) ventricles. Blood markers – known as “biomarkers” allow insight into underlying pathophysiologic mechanisms and biologic pathways, while predicting outcomes and guiding heart failure management and/or therapies. Content In this review, we provide an alternative approach to conceptualize heart failure biomarkers: the cardiomyocyte, its surrounding microenvironment, and the macroenvironment with clear interaction between these entities which may impact cellular processes involved in the pathogenesis and/or propagation of DCM. Newer biomarkers of left ventricular systolic dysfunction can be categorized under: (a) myocyte stress and stretch, (b) myocyte apoptosis, (c) cardiac interstitium, (d) inflammation, (e) oxidative stress, (f) cardiac energetics, (g) neurohormones and (h) renal biomarkers. Summary Biomarkers provide insight into the pathogenesis of DCM while predicting and potentially providing prognostic information in these patients with heart failure. PMID:23609585

Papillary muscles of right ventricle-morphological variations and its clinical relevance.

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Saha, Anubha; Roy, Sanchita

2018-02-09

Papillary muscle plays an important role in stabilizing the position of the tricuspid valve. Several pathologies can result in anatomical and functional abnormalities of the papillary muscles. The aim of the study is to deliberate the morphometry of papillary muscles in tricuspid valve and to analyze with the eminent research works previously done. The study was carried out in 52 formalin-fixed adult apparently normal cadaveric hearts belonging to either sex obtained from the Department of Anatomy. These hearts were dissected carefully to open the right ventricle and to expose the papillary muscles. Different morphological features of papillary muscles were noted, and measurements were taken. The classical picture of three papillary muscles existed in 23.07% of the specimens. Anterior papillary muscle was in all hearts, but posterior and septal muscle was off in 15.38% and 55.76%, respectively. Double and triple papillary muscles were seen too. Anterior and posterior muscle appeared predominantly flat-top and arose from the middle third (mostly), while septal muscle was chiefly conical and originated basically from the upper third of the ventricular wall. Chordopapillary relationship with tricuspid valve leaflets was beyond conventional. Mean length and breadth of anterior muscle were 2.19±0.59 cm and 0.76±0.26 cm, those of posterior muscle were 1.39±0.63 cm and 0.67±0.43 cm, and those of septal papillary muscle were 0.95±0.38 cm and 0.59±0.09 cm. Detailed knowledge of normal and variable anatomy of papillary muscles is not only necessary for better understanding of tricuspid pathologies but also valuable for successful newer surgical approaches in cardiac treatment. Copyright © 2018. Published by Elsevier Inc.

Cardiogenic shock as a complication of acute mitral valve regurgitation following posteromedial papillary muscle infarction in the absence of coronary artery disease

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Frati Giacomo

2008-11-01

Full Text Available Abstract A 48 year old man was transferred to our department with cardiogenic shock, pyrexia, a high white cell count and significant serum troponin T level. Clinical evaluation revealed severe mitral regurgitation secondary to a flail of both mitral valve leaflets. An emergency cardiac catheterisation did not reveal any significant coronary artery disease. Left ventricular angiogram and echocardiography demonstrated a good left ventricular function and massive mitral regurgitation. Blood cultures were negative for aerobics, anaerobics and fungi. The patient underwent emergency mitral valve replacement with a mechanical valve. Intraoperatively, the posteromedial papillary muscle was found to be ruptured. Histology of the papillary muscle revealed myocardial necrosis with no signs of infection. Cultures obtained from a mitral valve specimen were negative. The patient's recovery was uneventful and he was discharged on the 6th postoperative day.

Length dependence of force generation exhibit similarities between rat cardiac myocytes and skeletal muscle fibres.

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Hanft, Laurin M; McDonald, Kerry S

2010-08-01

According to the Frank-Starling relationship, increased ventricular volume increases cardiac output, which helps match cardiac output to peripheral circulatory demand. The cellular basis for this relationship is in large part the myofilament length-tension relationship. Length-tension relationships in maximally calcium activated preparations are relatively shallow and similar between cardiac myocytes and skeletal muscle fibres. During twitch activations length-tension relationships become steeper in both cardiac and skeletal muscle; however, it remains unclear whether length dependence of tension differs between striated muscle cell types during submaximal activations. The purpose of this study was to compare sarcomere length-tension relationships and the sarcomere length dependence of force development between rat skinned left ventricular cardiac myocytes and fast-twitch and slow-twitch skeletal muscle fibres. Muscle cell preparations were calcium activated to yield 50% maximal force, after which isometric force and rate constants (k(tr)) of force development were measured over a range of sarcomere lengths. Myofilament length-tension relationships were considerably steeper in fast-twitch fibres compared to slow-twitch fibres. Interestingly, cardiac myocyte preparations exhibited two populations of length-tension relationships, one steeper than fast-twitch fibres and the other similar to slow-twitch fibres. Moreover, myocytes with shallow length-tension relationships were converted to steeper length-tension relationships by protein kinase A (PKA)-induced myofilament phosphorylation. Sarcomere length-k(tr) relationships were distinct between all three cell types and exhibited patterns markedly different from Ca(2+) activation-dependent k(tr) relationships. Overall, these findings indicate cardiac myocytes exhibit varied length-tension relationships and sarcomere length appears a dominant modulator of force development rates. Importantly, cardiac myocyte length

Exercise thallium testing in ventricular preexcitation

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Archer, S.; Gornick, C.; Grund, F.; Shafer, R.; Weir, E.K.

1987-05-01

Ventricular preexcitation, as seen in Wolff-Parkinson-White syndrome, results in a high frequency of positive exercise electrocardiographic responses. Why this occurs is unknown but is not believed to reflect myocardial ischemia. Exercise thallium testing is often used for noninvasive assessment of coronary artery disease in patients with conditions known to result in false-positive electrocardiographic responses. To assess the effects of ventricular preexcitation on exercise thallium testing, 8 men (aged 42 +/- 4 years) with this finding were studied. No subject had signs or symptoms of coronary artery disease. Subjects exercised on a bicycle ergometer to a double product of 26,000 +/- 2,000 (+/- standard error of mean). All but one of the subjects had at least 1 mm of ST-segment depression. Tests were terminated because of fatigue or dyspnea and no patient had chest pain. Thallium test results were abnormal in 5 patients, 2 of whom had stress defects as well as abnormally delayed thallium washout. One of these subjects had normal coronary arteries on angiography with a negative ergonovine challenge, and both had normal exercise radionuclide ventriculographic studies. Delayed thallium washout was noted in 3 of the subjects with ventricular preexcitation and normal stress images. This study suggests that exercise thallium testing is frequently abnormal in subjects with ventricular preexcitation. Ventricular preexcitation may cause dyssynergy of ventricular activation, which could alter myocardial thallium handling, much as occurs with left bundle branch block. Exercise radionuclide ventriculography may be a better test for noninvasive assessment of coronary artery disease in patients with ventricular preexcitation.

Exercise thallium testing in ventricular preexcitation

International Nuclear Information System (INIS)

Archer, S.; Gornick, C.; Grund, F.; Shafer, R.; Weir, E.K.

1987-01-01

Ventricular preexcitation, as seen in Wolff-Parkinson-White syndrome, results in a high frequency of positive exercise electrocardiographic responses. Why this occurs is unknown but is not believed to reflect myocardial ischemia. Exercise thallium testing is often used for noninvasive assessment of coronary artery disease in patients with conditions known to result in false-positive electrocardiographic responses. To assess the effects of ventricular preexcitation on exercise thallium testing, 8 men (aged 42 +/- 4 years) with this finding were studied. No subject had signs or symptoms of coronary artery disease. Subjects exercised on a bicycle ergometer to a double product of 26,000 +/- 2,000 (+/- standard error of mean). All but one of the subjects had at least 1 mm of ST-segment depression. Tests were terminated because of fatigue or dyspnea and no patient had chest pain. Thallium test results were abnormal in 5 patients, 2 of whom had stress defects as well as abnormally delayed thallium washout. One of these subjects had normal coronary arteries on angiography with a negative ergonovine challenge, and both had normal exercise radionuclide ventriculographic studies. Delayed thallium washout was noted in 3 of the subjects with ventricular preexcitation and normal stress images. This study suggests that exercise thallium testing is frequently abnormal in subjects with ventricular preexcitation. Ventricular preexcitation may cause dyssynergy of ventricular activation, which could alter myocardial thallium handling, much as occurs with left bundle branch block. Exercise radionuclide ventriculography may be a better test for noninvasive assessment of coronary artery disease in patients with ventricular preexcitation

Exercise reveals impairments in left ventricular systolic function in patients with metabolic syndrome.

Science.gov (United States)

Fournier, Sara B; Reger, Brian L; Donley, David A; Bonner, Daniel E; Warden, Bradford E; Gharib, Wissam; Failinger, Conard F; Olfert, Melissa D; Frisbee, Jefferson C; Olfert, I Mark; Chantler, Paul D

2014-01-01

Metabolic syndrome (MetS) is the manifestation of a cluster of cardiovascular risk factors and is associated with a threefold increase in the risk of cardiovascular morbidity and mortality, which is suggested to be mediated, in part, by resting left ventricular (LV) systolic dysfunction. However, to what extent resting LV systolic function is impaired in MetS is controversial, and there are no data indicating whether LV systolic function is impaired during exercise. Accordingly, the objective of this study was to examine comprehensively the LV and arterial responses to exercise in individuals with MetS without diabetes and/or overt cardiovascular disease in comparison to a healthy control population. Cardiovascular function was characterized using Doppler echocardiography and gas exchange in individuals with MetS (n = 27) versus healthy control subjects (n = 20) at rest and during peak exercise. At rest, individuals with MetS displayed normal LV systolic function but reduced LV diastolic function compared with healthy control subjects. During peak exercise, individuals with MetS had impaired contractility, pump performance and vasodilator reserve capacity versus control subjects. A blunted contractile reserve response resulted in diminished arterial-ventricular coupling reserve and limited aerobic capacity in individuals with MetS versus control subjects. These findings are of clinical importance, because they provide insight into the pathophysiological changes in MetS that may predispose this population of individuals to an increased risk of cardiovascular morbidity and mortality.

Idiopathic ventricular tachycardia and fibrillation.

Science.gov (United States)

Belhassen, B; Viskin, S

1993-06-01

Important data have recently been added to our understanding of sustained ventricular tachyarrhythmias occurring in the absence of demonstrable heart disease. Idiopathic ventricular tachycardia (VT) is usually of monomorphic configuration and can be classified according to its site of origin as either right monomorphic (70% of all idiopathic VTs) or left monomorphic VT. Several physiopathological types of monomorphic VT can be presently individualized, according to their mode of presentation, their relationship to adrenergic stress, or their response to various drugs. The long-term prognosis is usually good. Idiopathic polymorphic VT is a much rarer type of arrhythmia with a less favorable prognosis. Idiopathic ventricular fibrillation may represent an underestimated cause of sudden cardiac death in ostensibly healty patients. A high incidence of inducibility of sustained polymorphic VT with programmed ventricular stimulation has been found by our group, but not by others. Long-term prognosis on Class IA antiarrhythmic medications that are highly effective at electrophysiologic study appears excellent.

Left Ventricular Function Improves after Pulmonary Valve Replacement in Patients with Previous Right Ventricular Outflow Tract Reconstruction and Biventricular Dysfunction

Science.gov (United States)

Kane, Colin; Kogon, Brian; Pernetz, Maria; McConnell, Michael; Kirshbom, Paul; Rodby, Katherine; Book, Wendy M.

2011-01-01

Congenital heart defects that have a component of right ventricular outflow tract obstruction, such as tetralogy of Fallot, are frequently palliated in childhood by disruption of the pulmonary valve. Although this can provide an initial improvement in quality of life, these patients are often left with severe pulmonary valve insufficiency. Over time, this insufficiency can lead to enlargement of the right ventricle and to the deterioration of right ventricular systolic and diastolic function. Pulmonary valve replacement in these patients decreases right ventricular volume overload and improves right ventricular performance. To date, few studies have examined the effects of pulmonary valve replacement on left ventricular function in patients with biventricular dysfunction. We sought to perform such an evaluation. Records of adult patients who had undergone pulmonary valve replacement from January 2003 through November 2006 were analyzed retrospectively. We reviewed preoperative and postoperative echocardiograms and calculated left ventricular function in 38 patients. In the entire cohort, the mean left ventricular ejection fraction increased by a mean of 0.07 after pulmonary valve replacement, which was a statistically significant change (P < 0.01). In patients with preoperative ejection fractions of less than 0.50, mean ejection fractions increased by 0.10. We conclude that pulmonary valve replacement in patients with biventricular dysfunction arising from severe pulmonary insufficiency and right ventricular enlargement can improve left ventricular function. Prospective studies are needed to verify this finding. PMID:21720459

Nonmotor fluctuations: phenotypes, pathophysiology, management, and open issues.

Science.gov (United States)

Classen, Joseph; Koschel, Jiri; Oehlwein, Christian; Seppi, Klaus; Urban, Peter; Winkler, Christian; Wüllner, Ullrich; Storch, Alexander

2017-08-01

Parkinson's disease (PD) is a neurodegenerative multisystem disorder characterized by progressive motor symptoms such as bradykinesia, tremor and muscle rigidity. Over the course of the disease, numerous non-motor symptoms, sometimes preceding the onset of motor symptoms, significantly impair patients' quality of life. The significance of non-motor symptoms may outweigh the burden through progressive motor incapacity, especially in later stages of the disease. The advanced stage of the disease is characterized by motor complications such as fluctuations and dyskinesias induced by the long-term application of levodopa therapy. In recent years, it became evident that various non-motor symptoms such as psychiatric symptoms, fatigue and pain also show fluctuations after chronic levodopa therapy (named non-motor fluctuations or NMFs). Although NMFs have moved into the focus of interest, current national guidelines on the treatment of PD may refer to non-motor symptoms and their management, but do not mention NMF, and do not contain recommendations on their management. The present article summarizes major issues related to NMF including clinical phenomenology and pathophysiology, and outlines a number of open issues and topics for future research.

Effects of (-)-desmethoxyverapamil on heart and vascular smooth muscle

International Nuclear Information System (INIS)

Nawrath, H.; Raschack, M.

1987-01-01

(-)-Desmethoxyverapamil [also known as (-)-devapamil or (-)-D888] has been developed as a verapamil type radioligand for the study of calcium channels. In the present investigation, the effects of (-)-desmethoxyverapamil on action potential (AP) and force of contraction in heart muscle preparations and on tension and 45 Ca influx in vascular smooth muscle are described. In part, the effects were compared with the (+)-isomer of desmethoxyverapamil and the isomers of both verapamil and methoxyverapamil. In atrial and/or ventricular heart muscle preparations from guinea pigs, cats and man, (-)-desmethoxyverapamil decreased the force of contraction and shortened the AP duration. Slow response APs were depressed, whereas dV/dtmax of phase 0 of the AP remained unchanged. The rank order of potency of the (-)-isomers was as follows: desmethoxyverapamil greater than methoxyverapamil greater than verapamil. Potassium-induced contractures and 45 Ca influx were depressed by the (-)-isomers of desmethoxyverapamil, methoxyverapamil and verapamil in the same potency rank order as observed in heart muscle. The (+)-isomers exerted qualitatively similar effects at about 10 to 200 times higher concentrations. Correspondingly, the increase in potency of the racemic mixtures of the drugs was accompanied by increases in stereoselectivity. It is concluded that (-)-desmethoxyverapamil is the most potent stereoselective calcium antagonist of the verapamil type with respect to its effects on heart and vascular smooth muscle

Effects of (-)-desmethoxyverapamil on heart and vascular smooth muscle

Energy Technology Data Exchange (ETDEWEB)

Nawrath, H.; Raschack, M.

1987-09-01

(-)-Desmethoxyverapamil (also known as (-)-devapamil or (-)-D888) has been developed as a verapamil type radioligand for the study of calcium channels. In the present investigation, the effects of (-)-desmethoxyverapamil on action potential (AP) and force of contraction in heart muscle preparations and on tension and /sup 45/Ca influx in vascular smooth muscle are described. In part, the effects were compared with the (+)-isomer of desmethoxyverapamil and the isomers of both verapamil and methoxyverapamil. In atrial and/or ventricular heart muscle preparations from guinea pigs, cats and man, (-)-desmethoxyverapamil decreased the force of contraction and shortened the AP duration. Slow response APs were depressed, whereas dV/dtmax of phase 0 of the AP remained unchanged. The rank order of potency of the (-)-isomers was as follows: desmethoxyverapamil greater than methoxyverapamil greater than verapamil. Potassium-induced contractures and /sup 45/Ca influx were depressed by the (-)-isomers of desmethoxyverapamil, methoxyverapamil and verapamil in the same potency rank order as observed in heart muscle. The (+)-isomers exerted qualitatively similar effects at about 10 to 200 times higher concentrations. Correspondingly, the increase in potency of the racemic mixtures of the drugs was accompanied by increases in stereoselectivity. It is concluded that (-)-desmethoxyverapamil is the most potent stereoselective calcium antagonist of the verapamil type with respect to its effects on heart and vascular smooth muscle.

Multivariable Dynamic Ankle Mechanical Impedance With Active Muscles

Science.gov (United States)

Lee, Hyunglae; Krebs, Hermano Igo; Hogan, Neville

2015-01-01

Multivariable dynamic ankle mechanical impedance in two coupled degrees-of-freedom (DOFs) was quantified when muscles were active. Measurements were performed at five different target activation levels of tibialis anterior and soleus, from 10% to 30% of maximum voluntary contraction (MVC) with increments of 5% MVC. Interestingly, several ankle behaviors characterized in our previous study of the relaxed ankle were observed with muscles active: ankle mechanical impedance in joint coordinates showed responses largely consistent with a second-order system consisting of inertia, viscosity, and stiffness; stiffness was greater in the sagittal plane than in the frontal plane at all activation conditions for all subjects; and the coupling between dorsiflexion–plantarflexion and inversion–eversion was small—the two DOF measurements were well explained by a strictly diagonal impedance matrix. In general, ankle stiffness increased linearly with muscle activation in all directions in the 2-D space formed by the sagittal and frontal planes, but more in the sagittal than in the frontal plane, resulting in an accentuated “peanut shape.” This characterization of young healthy subjects’ ankle mechanical impedance with active muscles will serve as a baseline to investigate pathophysiological ankle behaviors of biomechanically and/or neurologically impaired patients. PMID:25203497

The right ventricular response to ventricular hypofunction in anteroseptal infarction

International Nuclear Information System (INIS)

Kanayama, Sugako

1992-01-01

Thirty-seven patients with acute anteroseptal infarction but not significant right coronary artery stenosis were examined by using thallium-201 (Tl-201) myocardial perfusion SPECT to determine how the right ventricular (RV) free wall responded to a severely impaired ventricular septum. The patients were divided into the group in which RV free wall was visualized on Tl-201 myocardial SPECT (n=19, RV(+) Group) and the group in which it was not visualized (n=18, RV(-) Group). The relationship between visualization of RV free wall and both RV and left ventricular (LV) function was evaluated. RV(+) Group had larger extent of anteroseptal necrosis and severer impairment of RV free wall, as compared with RV(-) Group. LV ejection fraction (LVEF) was significantly lower in RV(+) Group than RV(-) Group in both acute and chronic phases. Although RV ejection fraction (RVEF) in acute phase was significantly lower in RV(+) Group than RV(-) Group, it did not differ in chronic phase between the two groups. In RV(+) Group, RV stroke work index (RVSWI), pulmonary artery end diastolic pressure (PAEDP), and mean pulmonary artery pressure (MPA) in chronic phase showed a statistically significant increase compared with those in acute phase; these hemodynamic variables in chronic phase were also significantly higher than those in RV(-) Group. RV/LV ratio inversely correlated with LVEF, and both necrotic extent and impairment severity positively correlated with both PAEDP and MPA. RV free wall could be visualized more clearly, corresponding to extremely decreased LV function. These findings suggest that RV free wall may play an important role in maintaining LV and RV function when ventricular septum is severely impaired by anteroseptal infarction. (N.K.)

β1-Adrenoceptor blocker aggravated ventricular arrhythmia.

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Wang, Yan; Patel, Dimpi; Wang, Dao Wu; Yan, Jiang Tao; Hsia, Henry H; Liu, Hao; Zhao, Chun Xia; Zuo, Hou Juan; Wang, Dao Wen

2013-11-01

To assess the impact of β1 -adrenoceptor blockers (β1 -blocker) and isoprenaline on the incidence of idiopathic repetitive ventricular arrhythmia that apparently decreases with preprocedural anxiety. From January 2010 to July 2012, six patients were identified who had idiopathic ventricular arrhythmias that apparently decreased (by greater than 90%) with preprocedural anxiety. The number of ectopic ventricular beats per hour (VPH) was calculated from Holter or telemetry monitoring to assess the ectopic burden. The mean VPH of 24 hours from Holter before admission (VPH-m) was used as baseline (100%) for normalization. β1 -Blockers, isoprenaline, and/or aminophylline were administrated successively on the ward and catheter lab to evaluate their effects on the ventricular arrhythmias. Among 97 consecutive patients with idiopathic ventricular arrhythmias, six had reduction in normalized VPHs in the hour before the scheduled procedure time from (104.6 ± 4.6%) to (2.8 ± 1.6%) possibly due to preprocedural anxiety (P < 0.05), then increased to (97.9 ± 9.7%) during β1 -blocker administration (P < 0.05), then quickly reduced to (1.6 ± 1.0%) during subsequent isoprenaline infusion. Repeated β1 -blocker quickly counteracted the inhibitory effect of isoprenaline, and VPHs increased to (120.9 ± 2.4%) from (1.6 ± 1.0%; P < 0.05). Isoprenaline and β1 -blocker showed similar effects on the arrhythmias in catheter lab. In some patients with structurally normal heart and ventricular arrhythmias there is a marked reduction of arrhythmias associated with preprocedural anxiety. These patients exhibit a reproducible sequence of β1 -blocker aggravation and catecholamine inhibition of ventricular arrhythmias, including both repetitive ventricular premature beats and monomorphic ventricular tachycardia. ©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc.

Left Ventricular Myocardial Function in Children With Pulmonary Hypertension: Relation to Right Ventricular Performance and Hemodynamics.

Science.gov (United States)

Burkett, Dale A; Slorach, Cameron; Patel, Sonali S; Redington, Andrew N; Ivy, D Dunbar; Mertens, Luc; Younoszai, Adel K; Friedberg, Mark K

2015-08-01

Through ventricular interdependence, pulmonary hypertension (PH) induces left ventricular (LV) dysfunction. We hypothesized that LV strain/strain rate, surrogate measures of myocardial contractility, are reduced in pediatric PH and relate to invasive hemodynamics, right ventricular strain, and functional measures of PH. At 2 institutions, echocardiography was prospectively performed in 54 pediatric PH patients during cardiac catheterization, and in 54 matched controls. Patients with PH had reduced LV global longitudinal strain (LS; -18.8 [-17.3 to -20.4]% versus -20.2 [-19.0 to -20.9]%; P=0.0046) predominantly because of reduced basal (-12.9 [-10.8 to -16.3]% versus -17.9 [-14.5 to -20.7]%; Pright ventricular free-wall LS (r=0.64; PBrain natriuretic peptide levels correlated moderately with septal LS (r=0.48; P=0.0038). PH functional class correlated moderately with LV free-wall LS (r=-0.48; P=0.0051). The septum, shared between ventricles and affected by septal shift, was the most affected LV region in PH. Pediatric PH patients demonstrate reduced LV strain/strain rate, predominantly within the septum, with relationships to invasive hemodynamics, right ventricular strain, and functional PH measures. © 2015 American Heart Association, Inc.

Transient Ischemic Attack and Ischemic Stroke in Danon Disease with Formation of Left Ventricular Apical Thrombus despite Normal Systolic Function

OpenAIRE

Tsuda, Takeshi; Shillingford, Amanda J.; Vetter, Jane; Kandula, Vinay; Jain, Badal; Temple, Joel

2017-01-01

Danon disease is a rare X-linked dominant skeletal and cardiac muscle disorder presenting with hypertrophic cardiomyopathy, Wolf-Parkinson-White syndrome, skeletal myopathy, and mild intellectual disability. Early morbidity and mortality due to heart failure or sudden death are known in Danon disease, more in males than in females. Here, we present a 17-year-old female adolescent with Danon disease and severe concentric hypertrophy with normal left ventricular (LV) systolic function, who has ...

Right ventricular involvement in cardiac sarcoidosis demonstrated with cardiac magnetic resonance.

Science.gov (United States)

Smedema, Jan-Peter; van Geuns, Robert-Jan; Ainslie, Gillian; Ector, Joris; Heidbuchel, Hein; Crijns, Harry J G M

2017-11-01

Cardiac involvement in sarcoidosis is reported in up to 30% of patients. Left ventricular involvement demonstrated by contrast-enhanced cardiac magnetic resonance has been well validated. We sought to determine the prevalence and distribution of right ventricular late gadolinium enhancement in patients diagnosed with pulmonary sarcoidosis. We prospectively evaluated 87 patients diagnosed with pulmonary sarcoidosis with contrast-enhanced cardiac magnetic resonance for right ventricular involvement. Pulmonary artery pressures were non-invasively evaluated with Doppler echocardiography. Patient characteristics were compared between the groups with and without right ventricular involvement, and right ventricular enhancement was correlated with pulmonary hypertension, ventricular mass, volume, and systolic function. Left ventricular late gadolinium enhancement was demonstrated in 30 patients (34%). Fourteen patients (16%) had right ventricular late gadolinium enhancement, with sole right ventricular enhancement in only two patients. The pattern of right ventricular enhancement consisted of right ventricular outflow tract enhancement in 1 patient, free wall enhancement in 8 patients, ventricular insertion point enhancement in 10 patients, and enhancement of the right side of the interventricular septum in 11 patients. Pulmonary arterial hypertension correlated with the presence of right ventricular enhancement (P Right ventricular enhancement correlated with systolic ventricular dysfunction (P Right ventricular enhancement was present in 16% of patients diagnosed with pulmonary sarcoidosis and in 48% of patients with left ventricular enhancement. The presence of right ventricular enhancement correlated with pulmonary arterial hypertension, right ventricular systolic dysfunction, hypertrophy, and dilation. © 2017 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of the European Society of Cardiology.

Impact of the right ventricular lead position on clinical outcome and on the incidence of ventricular tachyarrhythmias in patients with CRT-D

DEFF Research Database (Denmark)

Kutyifa, Valentina; Bloch Thomsen, Poul Erik; Huang, David T.

2013-01-01

Data on the impact of right ventricular (RV) lead location on clinical outcome and ventricular tachyarrhythmias in cardiac resynchronization therapy with defibrillator (CRT-D) patients are limited.......Data on the impact of right ventricular (RV) lead location on clinical outcome and ventricular tachyarrhythmias in cardiac resynchronization therapy with defibrillator (CRT-D) patients are limited....

Immunohistochemical analysis of laryngeal muscles in normal horses and horses with subclinical recurrent laryngeal neuropathy.

Science.gov (United States)

Rhee, Hannah S; Steel, Catherine M; Derksen, Frederik J; Robinson, N Edward; Hoh, Joseph F Y

2009-08-01

We used immunohistochemistry to examine myosin heavy-chain (MyHC)-based fiber-type profiles of the right and left cricoarytenoideus dorsalis (CAD) and arytenoideus transversus (TrA) muscles of six horses without laryngoscopic evidence of recurrent laryngeal neuropathy (RLN). Results showed that CAD and TrA muscles have the same slow, 2a, and 2x fibers as equine limb muscles, but not the faster contracting fibers expressing extraocular and 2B MyHCs found in laryngeal muscles of small mammals. Muscles from three horses showed fiber-type grouping bilaterally in the TrA muscles, but only in the left CAD. Fiber-type grouping suggests that denervation and reinnervation of fibers had occurred, and that these horses had subclinical RLN. There was a virtual elimination of 2x fibers in these muscles, accompanied by a significant increase in the percentage of 2a and slow fibers, and hypertrophy of these fiber types. The results suggest that multiple pathophysiological mechanisms are at work in early RLN, including selective denervation and reinnervation of 2x muscle fibers, corruption of neural impulse traffic that regulates 2x and slow muscle fiber types, and compensatory hypertrophy of remaining fibers. We conclude that horses afflicted with mild RLN are able to remain subclinical by compensatory hypertrophy of surviving muscle fibers.

Right ventricular strain in heart failure: Clinical perspective.

Science.gov (United States)

Tadic, Marijana; Pieske-Kraigher, Elisabeth; Cuspidi, Cesare; Morris, Daniel A; Burkhardt, Franziska; Baudisch, Ana; Haßfeld, Sabine; Tschöpe, Carsten; Pieske, Burket

2017-10-01

The number of studies demonstrating the importance of right ventricular remodelling in a wide range of cardiovascular diseases has increased in the past two decades. Speckle-tracking imaging provides new variables that give comprehensive information about right ventricular function and mechanics. In this review, we summarize current knowledge of right ventricular mechanics in heart failure with reduced ejection fraction and preserved ejection fraction. We searched PubMed, MEDLINE, Ovid and Embase databases for studies published from January 2000 to December 2016 in the English language using the following keywords: "right ventricle"; "strain"; "speckle tracking"; "heart failure with reduced ejection fraction"; and "heart failure with preserved ejection fraction". Investigations showed that right ventricular dysfunction is associated with higher cardiovascular and overall mortality in patients with heart failure, irrespective of ejection fraction. The number of studies investigating right ventricular strain in patients with heart failure with reduced ejection fraction is constantly increasing, whereas data on right ventricular mechanics in patients with heart failure with preserved ejection fraction are limited. Given the high feasibility, accuracy and clinical implications of right ventricular strain in the population with heart failure, it is of great importance to try to include the evaluation of right ventricular strain as a regular part of each echocardiographic examination in patients with heart failure. However, further investigations are necessary to establish right ventricular strain as a standard variable for decision-making. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Right ventricular function in patients with dilated cardiomyopathy

International Nuclear Information System (INIS)

Kubota, Shuhei; Kubota, Sachio; Iwase, Takashi; Iizuka, Toshio; Imai, Susumu; Murata, Kazuhiko; Inoue, Tomio; Suzuki, Tadashi; Sasaki, Yasuhito.

1993-01-01

The characteristics and pathogenesis of right ventricular dysfunction in 14 patients with dilated cardiomyopathy (DCM) were investigated by equilibrium right ventricular blood pool scintigraphy using ultrashort-lifetime 81m Kr. Thirteen patients with severe left ventricular dysfunction due to old anterior myocardial infarction (OMI) and nine normal subjects were used as controls. The right ventricular end-diastolic pressure and volume index, mean pulmonary arterial pressure, and total pulmonary vascular resistance index were almost the same in the DCM and OMI patients. The right ventricular ejection fraction was 44.2±6.0% (mean±SD) in DCM patients and 47.1±7.9% in OMI patients, both significantly lower than those in the normal subjects (54.5±5.3%), but with no difference between the two case groups. The right ventricular peak filling rate was significantly reduced in both case groups as compared with the normal subjects (2.46±0.81 EDV/sec). The reduction was significantly greater (p 81m Kr blood pool scintigraphy is useful in the study of the right ventricular systolic and diastolic function. The diastolic parameters are more sensitive indicators for evaluation of right ventricular function in DCM than the systolic parameters. (author)

Arrhythmogenic right ventricular cardiomyopathy in a dog : case report

Directory of Open Access Journals (Sweden)

A.J. Möhr

2000-07-01

Full Text Available An 8-month-old Labrador retriever bitch was evaluated for sudden-onset, progressive abdominal distension. Physical examination revealed an exaggerated inspiratory effort, severe ascites, bilateral jugular vein distension, and hypokinetic femoral arterial pulses. Thoracic auscultation detected tachycardia with muffled heart sounds, without audible cardiac murmurs. Thoracic radiographs identified severe right ventricular enlargement and pleural effusion. The electrocardiogram was consistent with incomplete right bundle branch block or right ventricular enlargement. Echocardiography demonstrated severe right ventricular and atrial dilation, secondary tricuspid regurgitation, and thinning and hypocontractility of the right ventricular myocardium. Left heart chamber sizes were slightly decreased, with normal left ventricular contractility. Adiagnosis of arrhythmogenic right ventricular cardiomyopathy was reached, based on the characteristic clinical, electrocardiographic, radiographic and echocardiographic findings, and the exclusion of other causes of isolated right ventricular failure. Treatment effected good control of clinical signs, until acutely decompensated congestive right heart failure led to euthanasia after 4 months. Arrhythmogenic right ventricular cardiomyopathy is a well-described clinical entity in humans, and has previously been documented in 3 male dogs. The condition is characterised by progressive fibro-adipose replacement of right ventricular myocardium, while the left ventricle usually remains unaffected. It should be considered a differential diagnosis in any young dog presented with isolated right heart failure, syncope, or unexplained ventricular tachyarrhythmias. This article reports the 1st case of arrhythmogenic right ventricular cardiomyopathy in a female dog, and highlights its echocardiographic features.

The influence of type 2 diabetes and gender on ventricular repolarization dispersion in patients with sub-clinic left ventricular diastolic dysfunction

OpenAIRE

Jani, Ylber; Kamberi, Ahmet; Xhunga, Sotir; Pocesta, Bekim; Ferati, Fatmir; Lala, Dali; Zeqiri, Agim; Rexhepi, Atila

2015-01-01

Objective: To assess the influence of type 2 DM and gender, on the QT dispersion, Tpeak-Tend dispersion of ventricular repolarization, in patients with sub-clinic left ventricular diastolic dysfunction of the heart. Background: QT dispersion, that reflects spatial inhomogeneity in ventricular repolarization, Tpeak-Tend dispersion, this on the other hand reflects transmural inhomogeneity in ventricular repolarization, that is increased in an early stage of cardiomyopathy, and in patients with ...

Skeletal muscle-specific overexpression of IGFBP-2 promotes a slower muscle phenotype in healthy but not dystrophic mdx mice and does not affect the dystrophic pathology.

Science.gov (United States)

Swiderski, Kristy; Martins, Karen Janet Bernice; Chee, Annabel; Trieu, Jennifer; Naim, Timur; Gehrig, Stefan Martin; Baum, Dale Michael; Brenmoehl, Julia; Chau, Luong; Koopman, René; Gregorevic, Paul; Metzger, Friedrich; Hoeflich, Andreas; Lynch, Gordon Stuart

The insulin-like growth factor binding proteins (IGFBPs) are thought to modulate cell size and homeostasis via IGF-I-dependent and -independent pathways. There is a considerable dearth of information regarding the function of IGFBPs in skeletal muscle, particularly their role in the pathophysiology of Duchenne muscular dystrophy (DMD). In this study we tested the hypothesis that intramuscular IGFBP-2 overexpression would ameliorate the pathology in mdx dystrophic mice. 4week old male C57Bl/10 and mdx mice received a single intramuscular injection of AAV6-empty or AAV6-IGFBP-2 vector into the tibialis anterior muscle. At 8weeks post-injection the effect of IGFBP-2 overexpression on the structure and function of the injected muscle was assessed. AAV6-mediated IGFBP-2 overexpression in the tibialis anterior (TA) muscles of 4-week-old C57BL/10 and mdx mice reduced the mass of injected muscle after 8weeks, inducing a slower muscle phenotype in C57BL/10 but not mdx mice. Analysis of inflammatory and fibrotic gene expression revealed no changes between control and IGFBP-2 injected muscles in dystrophic (mdx) mice. Together these results indicate that the IGFBP-2-induced promotion of a slower muscle phenotype is impaired in muscles of dystrophin-deficient mdx mice, which contributes to the inability of IGFBP-2 to ameliorate the dystrophic pathology. The findings implicate the dystrophin-glycoprotein complex (DGC) in the signaling required for this adaptation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Active and Passive Components of Pelvic Floor Muscle Tone in Women with Provoked Vestibulodynia: A Perspective Based on a Review of the Literature.

Science.gov (United States)

Thibault-Gagnon, Stéphanie; Morin, Mélanie

2015-11-01

Pelvic floor muscle (PFM) dysfunctions, especially elevated tone or tension, are suggested to play an important role in the pathophysiology of provoked vestibulodynia (PVD). However, the involvement of the PFMs remains misunderstood as the assessment of muscle tone is complex and requires a thorough understanding of muscle physiology in relation to the characteristics and limitations of current PFM assessment tools. The aim of this review was to describe the structures and mechanisms involved in muscle tone in normally innervated muscle, and to discuss and relate these concepts to the PFM findings in women with PVD. A narrative overview of the literature retrieved from searches of electronic databases and hand searches. Muscle tone in a normally innervated muscle comprises both active (contractile) and passive (viscoelastic) components. Current methods for evaluating PFM tone such as digital palpation, ultrasound imaging, pressure perineometry, dynamometry, and electromyography may evaluate different components. Research findings suggestive of PFM hypertonicity in women with PVD include elevated general PFM tone, changes in viscoelastic properties, and at least in some women, abnormal increases in electrogenic activity. There is a growing body of evidence to support the involvement of PFM hypertonicity in the pathophysiology of PVD. Limitations of the instruments as well as their properties should be considered when evaluating PFM tone in order to obtain better insight into which component of PFM tone is assessed. Future research is required for further investigating the underlying mechanisms of PFM hypertonicity, and studying the specific effects of physiotherapeutic interventions on PFM tone in women with PVD. © 2015 International Society for Sexual Medicine.

Is right ventricular mid-septal pacing superior to apical pacing in patients with high degree atrio-ventricular block and moderately depressed left ventricular function?

Science.gov (United States)

Chen, Kang; Mao, Ye; Liu, Shao-hua; Wu, Qiong; Luo, Qing-zhi; Pan, Wen-qi; Jin, Qi; Zhang, Ning; Ling, Tian-you; Chen, Ying; Gu, Gang; Shen, Wei-feng; Wu, Li-qun

2014-06-01

We are aimed to investigate whether right ventricular mid-septal pacing (RVMSP) is superior to conventional right ventricular apical pacing (RVAP) in improving clinical functional capacity and left ventricular ejection fraction (LVEF) for patients with high-degree atrio-ventricular block and moderately depressed left ventricle (LV) function. Ninety-two patients with high-degree atrio-ventricular block and moderately reduced LVEF (ranging from 35% to 50%) were randomly allocated to RVMSP (n=45) and RVAP (n=47). New York Heart Association (NYHA) functional class, echocardiographic LVEF, and distance during a 6-min walk test (6MWT) were determined at 18 months after pacemaker implantation. Serum levels of N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured using an enzyme-linked immunosorbent assay (ELISA) kit. Compared with baseline, NYHA functional class remained unchanged at 18 months, distance during 6MWT (485 m vs. 517 m) and LVEF (36.7% vs. 41.8%) were increased, but BNP levels were reduced (2352 pg/ml vs. 710 pg/ml) in the RVMSP group compared with those in the RVAP group, especially in patients with LVEF 35%-40% (for all comparisons, Pfunction capacity and LV function measurements were not significantly changed in patients with RVAP, despite the pacing measurements being similar in both groups, such as R-wave amplitude and capture threshold. RVMSP provides a better clinical utility, compared with RVAP, in patients with high-degree atrioventricular block and moderately depressed LV function whose LVEF levels ranged from 35% to 40%.

Current concepts in the pathophysiology of glaucoma

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Agarwal Renu

2009-01-01

Full Text Available Glaucoma, the second leading cause of blindness, is characterized by changes in the optic disc and visual field defects. The elevated intraocular pressure was considered the prime factor responsible for the glaucomatous optic neuropathy involving death of retinal ganglion cells and their axons. Extensive investigations into the pathophysiology of glaucoma now reveal the role of multiple factors in the development of retinal ganglion cell death. A better understanding of the pathophysiological mechanisms involved in the onset and progression of glaucomatous optic neuropathy is crucial in the development of better therapeutic options. This review is an effort to summarize the current concepts in the pathophysiology of glaucoma so that newer therapeutic targets can be recognized. The literature available in the National Medical Library and online Pubmed search engine was used for literature review.

Progressive Muscle Atrophy and Weakness After Treatment by Mantle Field Radiotherapy in Hodgkin Lymphoma Survivors

International Nuclear Information System (INIS)

Leeuwen-Segarceanu, Elena M. van; Dorresteijn, Lucille D.A.; Pillen, Sigrid; Biesma, Douwe H.; Vogels, Oscar J.M.; Alfen, Nens van

2012-01-01

Purpose: To describe the damage to the muscles and propose a pathophysiologic mechanism for muscle atrophy and weakness after mantle field radiotherapy in Hodgkin lymphoma (HL) survivors. Methods and Materials: We examined 12 patients treated by mantle field radiotherapy between 1969 and 1998. Besides evaluation of their symptoms, the following tests were performed: dynamometry; ultrasound of the sternocleidomastoid, biceps, and antebrachial flexor muscles; and needle electromyography of the neck, deltoid, and ultrasonographically affected arm muscles. Results: Ten patients (83%) experienced neck complaints, mostly pain and muscle weakness. On clinical examination, neck flexors were more often affected than neck extensors. On ultrasound, the sternocleidomastoid was severely atrophic in 8 patients, but abnormal echo intensity was seen in only 3 patients. Electromyography of the neck muscles showed mostly myogenic changes, whereas the deltoid, biceps, and antebrachial flexor muscles seemed to have mostly neurogenic damage. Conclusions: Many patients previously treated by mantle field radiotherapy develop severe atrophy and weakness of the neck muscles. Neck muscles within the radiation field show mostly myogenic damage, and muscles outside the mantle field show mostly neurogenic damage. The discrepancy between echo intensity and atrophy suggests that muscle damage is most likely caused by an extrinsic factor such as progressive microvascular fibrosis. This is also presumed to cause damage to nerves within the radiated field, resulting in neurogenic damage of the deltoid and arm muscles.

The pathophysiology of Peyronie's disease.

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El-Sakka, Ahmed I; Salabas, Emre; Dinçer, Murat; Kadioglu, Ates

2013-09-01

To review the contemporary knowledge of the pathophysiology of Peyronie's disease (PD). Medline was searched for papers published in English from 2000 to March 2013, using the keywords 'Peyronie's disease' and 'pathophysiology'. More than 300 relevant articles were identified for the purpose of this review. Unfortunately only a few studies had a high level of evidence, and the remaining studies were not controlled in their design. Many theories have been proposed to explain the cause of PD, but the true pathogenesis of PD remains an enigma. Identifying particular growth factors and the specific genes responsible for the induction of PD have been the ultimate goal of research over the past several decades. This would provide the means to devise a possible gene therapy for this devastating condition. We discuss present controversies and new discoveries related to the pathophysiology of this condition. PD is one of the most puzzling diseases in urology. The pathogenesis remains uncertain and there is still controversy about the best management. The pathogenesis of PD has been explored in animal models, cell cultures and clinical trials, but the results have led to further questions. New research on the aetiology and pathogenesis of PD is needed, and which will hopefully improve the understanding and management for patients with this frustrating disease.

Noninvasive reconstruction of the three-dimensional ventricular activation sequence during pacing and ventricular tachycardia in the rabbit heart.

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Han, Chengzong; Pogwizd, Steven M; Killingsworth, Cheryl R; He, Bin

2011-01-01

Ventricular arrhythmias represent one of leading causes for sudden cardiac death, a significant problem in public health. Noninvasive imaging of cardiac electric activities associated with ventricular arrhythmias plays an important role in better our understanding of the mechanisms and optimizing the treatment options. The present study aims to rigorously validate a novel three-dimensional (3-D) cardiac electrical imaging (3-DCEI) technique with the aid of 3-D intra-cardiac mapping during paced rhythm and ventricular tachycardia (VT) in the rabbit heart. Body surface potentials and intramural bipolar electrical recordings were simultaneously measured in a closed-chest condition in thirteen healthy rabbits. Single-site pacing and dual-site pacing were performed from ventricular walls and septum. VTs and premature ventricular complexes (PVCs) were induced by intravenous norepinephrine (NE). The non-invasively imaged activation sequence correlated well with invasively measured counterparts, with a correlation coefficient of 0.72 and a relative error of 0.30 averaged over all paced beats and NE-induced PVCs and VT beats. The averaged distance from imaged site of initial activation to measured site determined from intra-cardiac mapping was ∼5mm. These promising results suggest that 3-DCEI is feasible to non-invasively localize the origins and image activation sequence of focal ventricular arrhythmias.

Role of Protein Carbonylation in Skeletal Muscle Mass Loss Associated with Chronic Conditions

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Esther Barreiro

2016-05-01

Full Text Available Muscle dysfunction, characterized by a reductive remodeling of muscle fibers, is a common systemic manifestation in highly prevalent conditions such as chronic heart failure (CHF, chronic obstructive pulmonary disease (COPD, cancer cachexia, and critically ill patients. Skeletal muscle dysfunction and impaired muscle mass may predict morbidity and mortality in patients with chronic diseases, regardless of the underlying condition. High levels of oxidants may alter function and structure of key cellular molecules such as proteins, DNA, and lipids, leading to cellular injury and death. Protein oxidation including protein carbonylation was demonstrated to modify enzyme activity and DNA binding of transcription factors, while also rendering proteins more prone to proteolytic degradation. Given the relevance of protein oxidation in the pathophysiology of many chronic conditions and their comorbidities, the current review focuses on the analysis of different studies in which the biological and clinical significance of the modifications induced by reactive carbonyls on proteins have been explored so far in skeletal muscles of patients and animal models of chronic conditions such as COPD, disuse muscle atrophy, cancer cachexia, sepsis, and physiological aging. Future research will elucidate the specific impact and sites of reactive carbonyls on muscle protein content and function in human conditions.

Activation of UCPs gene expression in skeletal muscle can be independent on both circulating fatty acids and food intake. Involvement of ROS in a model of mouse cancer cachexia.

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Busquets, Sílvia; Almendro, Vanessa; Barreiro, Esther; Figueras, Maite; Argilés, Josep M; López-Soriano, Francisco J

2005-01-31

Implantation of a fast growing tumour to mice (Lewis lung carcinoma) resulted in a clear cachectic state characterized by a profound muscle wasting. This was accompanied by a significant increase in both UCP2 and UCP3 gene expression in skeletal muscle and heart. Interestingly, this increase in gene expression was not linked to a rise in circulating fatty acids or in a decrease in food intake, as previously reported in other pathophysiological states. These results question the concept that hyperlipaemia is the only factor controlling UCP gene expression in different pathophysiological conditions. In addition, the present work suggests that UCPs might participate in a counter-regulatory mechanism to lower the production of ROS.

A vicious circle in chronic lymphoedema pathophysiology?

DEFF Research Database (Denmark)

Cucchi, F; Rossmeislova, L; Simonsen, L

2017-01-01

Chronic lymphoedema is a disease caused by a congenital or acquired damage to the lymphatic system and characterized by complex chains of pathophysiologic events such as lymphatic fluid stasis, chronic inflammation, lymphatic vessels impairment, adipose tissue deposition and fibrosis. These event....... Together, these observations indicate strong reciprocal relationship between lymphatics and adipose tissue and suggest a possible key role of the adipocyte in the pathophysiology of chronic lymphoedema's vicious circle....

Delayed recovery of right ventricular systolic function after repair of long-standing tricuspid regurgitation associated with severe right ventricular failure.

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Kim, Jong Hun; Kim, Kyung Hwa; Choi, Jong Bum; Kuh, Ja Hong

2016-03-01

After tricuspid valve surgery for long-standing tricuspid regurgitation associated with right ventricular failure, reverse remodelling of the enlarged right ventricle, including recovery of right ventricular systolic function, is unpredictable. We present the case of a 31-year old man with early reduction of dilated right ventricular dimensions and delayed recovery of impaired right ventricular systolic function after valve repair for traumatic tricuspid regurgitation lasting 16 years. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Correlation of trabeculae and papillary muscles with clinical and cardiac characteristics and impact on CMR measures of LV anatomy and function

NARCIS (Netherlands)

Chuang, Michael L.; Gona, Philimon; Hautvast, Gilion L T F; Salton, Carol J.; Blease, Susan J.; Yeon, Susan B.; Breeuwer, Marcel; O'Donnell, Christopher J.; Manning, Warren J.

2012-01-01

Objectives: The goal of this study was to assess the relationship of left ventricular (LV) trabeculae and papillary muscles (TPM) with clinical characteristics in a community-based, free-living adult cohort and to determine the effect of TPM on quantitative measures of LV volume, mass, and ejection

Angiotensin II Infusion Induces Marked Diaphragmatic Skeletal Muscle Atrophy

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Rezk, Bashir M.; Yoshida, Tadashi; Semprun-Prieto, Laura; Higashi, Yusuke; Sukhanov, Sergiy; Delafontaine, Patrice

2012-01-01

Advanced congestive heart failure (CHF) and chronic kidney disease (CKD) are characterized by increased angiotensin II (Ang II) levels and are often accompanied by significant skeletal muscle wasting that negatively impacts mortality and morbidity. Both CHF and CKD patients have respiratory muscle dysfunction, however the potential effects of Ang II on respiratory muscles are unknown. We investigated the effects of Ang II on diaphragm muscle in FVB mice. Ang II induced significant diaphragm muscle wasting (18.7±1.6% decrease in weight at one week) and reduction in fiber cross-sectional area. Expression of the E3 ubiquitin ligases atrogin-1 and muscle ring finger-1 (MuRF-1) and of the pro-apoptotic factor BAX was increased after 24 h of Ang II infusion (4.4±0.3 fold, 3.1±0.5 fold and 1.6±0.2 fold, respectively, compared to sham infused control) suggesting increased muscle protein degradation and apoptosis. In Ang II infused animals, there was significant regeneration of injured diaphragm muscles at 7 days as indicated by an increase in the number of myofibers with centralized nuclei and high expression of embryonic myosin heavy chain (E-MyHC, 11.2±3.3 fold increase) and of the satellite cell marker M-cadherin (59.2±22.2% increase). Furthermore, there was an increase in expression of insulin-like growth factor-1 (IGF-1, 1.8±0.3 fold increase) in Ang II infused diaphragm, suggesting the involvement of IGF-1 in diaphragm muscle regeneration. Bone-marrow transplantation experiments indicated that although there was recruitment of bone-marrow derived cells to the injured diaphragm in Ang II infused mice (267.0±74.6% increase), those cells did not express markers of muscle stem cells or regenerating myofibers. In conclusion, Ang II causes marked diaphragm muscle wasting, which may be important for the pathophysiology of respiratory muscle dysfunction and cachexia in conditions such as CHF and CKD. PMID:22276172

Angiotensin II infusion induces marked diaphragmatic skeletal muscle atrophy.

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Bashir M Rezk

Full Text Available Advanced congestive heart failure (CHF and chronic kidney disease (CKD are characterized by increased angiotensin II (Ang II levels and are often accompanied by significant skeletal muscle wasting that negatively impacts mortality and morbidity. Both CHF and CKD patients have respiratory muscle dysfunction, however the potential effects of Ang II on respiratory muscles are unknown. We investigated the effects of Ang II on diaphragm muscle in FVB mice. Ang II induced significant diaphragm muscle wasting (18.7±1.6% decrease in weight at one week and reduction in fiber cross-sectional area. Expression of the E3 ubiquitin ligases atrogin-1 and muscle ring finger-1 (MuRF-1 and of the pro-apoptotic factor BAX was increased after 24 h of Ang II infusion (4.4±0.3 fold, 3.1±0.5 fold and 1.6±0.2 fold, respectively, compared to sham infused control suggesting increased muscle protein degradation and apoptosis. In Ang II infused animals, there was significant regeneration of injured diaphragm muscles at 7 days as indicated by an increase in the number of myofibers with centralized nuclei and high expression of embryonic myosin heavy chain (E-MyHC, 11.2±3.3 fold increase and of the satellite cell marker M-cadherin (59.2±22.2% increase. Furthermore, there was an increase in expression of insulin-like growth factor-1 (IGF-1, 1.8±0.3 fold increase in Ang II infused diaphragm, suggesting the involvement of IGF-1 in diaphragm muscle regeneration. Bone-marrow transplantation experiments indicated that although there was recruitment of bone-marrow derived cells to the injured diaphragm in Ang II infused mice (267.0±74.6% increase, those cells did not express markers of muscle stem cells or regenerating myofibers. In conclusion, Ang II causes marked diaphragm muscle wasting, which may be important for the pathophysiology of respiratory muscle dysfunction and cachexia in conditions such as CHF and CKD.

Right Ventricular Pseudoaneurysm Following Endomyocardial Biopsy.

Science.gov (United States)

Pita; Santos; Manteiga; Rodriguez; Beiras

1996-03-01

Ventricular perforation is an unusual complication after endomyocardial biopsy in heart transplanted patients. We report a case of asymptomatic right ventricular perforation and pseudoaneurysm formation, secondary to endomyocardial biopsy, diagnosed by angiography. The spontaneous obliteration of the pseudoaneurysm was observed.

Evaluation of right ventricular volumes measured by magnetic resonance imaging

DEFF Research Database (Denmark)

Møgelvang, J; Stubgaard, M; Thomsen, C

1988-01-01

stroke volume was calculated as the difference between end-diastolic and end-systolic volume and compared to left ventricular stroke volume and to stroke volume determined simultaneously by a classical indicator dilution technique. There was good agreement between right ventricular stroke volume......Right ventricular volumes were determined in 12 patients with different levels of right and left ventricular function by magnetic resonance imaging (MRI) using an ECG gated multisection technique in planes perpendicular to the diastolic position of the interventricular septum. Right ventricular...... determined by MRI and by the indicator dilution method and between right and left ventricular stroke volume determined by MRI. Thus, MRI gives reliable values not only for left ventricular volumes, but also for right ventricular volumes. By MRI it is possible to obtain volumes from both ventricles...

Adeno-Associated Virus Serotype 9–Driven Expression of BAG3 Improves Left Ventricular Function in Murine Hearts With Left Ventricular Dysfunction Secondary to a Myocardial Infarction

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Tijana Knezevic, PhD

2016-12-01

Full Text Available Mutations in Bcl-2–associated athanogene 3 (BAG3 were associated with skeletal muscle dysfunction and dilated cardiomyopathy. Retro-orbital injection of an adeno-associated virus serotype 9 expressing BAG3 (rAAV9-BAG3 significantly (p < 0.0001 improved left ventricular ejection fraction, fractional shortening, and stroke volume 9 days post-injection in mice with cardiac dysfunction secondary to a myocardial infarction. Furthermore, myocytes isolated from mice 3 weeks after injection showed improved cell shortening, enhanced systolic [Ca2+]i and increased [Ca2+]i transient amplitudes, and increased maximal L-type Ca2+ current amplitude. These results suggest that BAG3 gene therapy may provide a novel therapeutic option for the treatment of heart failure.

Statin-associated muscle symptoms: impact on statin therapy—European Atherosclerosis Society Consensus Panel Statement on Assessment, Aetiology and Management

Science.gov (United States)

Stroes, Erik S.; Thompson, Paul D.; Corsini, Alberto; Vladutiu, Georgirene D.; Raal, Frederick J.; Ray, Kausik K.; Roden, Michael; Stein, Evan; Tokgözoğlu, Lale; Nordestgaard, Børge G.; Bruckert, Eric; De Backer, Guy; Krauss, Ronald M.; Laufs, Ulrich; Santos, Raul D.; Hegele, Robert A.; Hovingh, G. Kees; Leiter, Lawrence A.; Mach, Francois; März, Winfried; Newman, Connie B.; Wiklund, Olov; Jacobson, Terry A.; Catapano, Alberico L.; Chapman, M. John; Ginsberg, Henry N.; Stroes, Erik; Thompson, Paul D.; Corsini, Alberto; Vladutiu, Georgirene D.; Raal, Frederick J.; Ray, Kausik K.; Roden, Michael; Stein, Evan; Tokgözoğlu, Lale; Nordestgaard, Børge G.; Bruckert, Eric; Krauss, Ronald M.; Laufs, Ulrich; Santos, Raul D.; März, Winfried; Newman, Connie B.; John Chapman, M.; Ginsberg, Henry N.; John Chapman, M.; Ginsberg, Henry N.; de Backer, Guy; Catapano, Alberico L.; Hegele, Robert A.; Kees Hovingh, G.; Jacobson, Terry A.; Leiter, Lawrence; Mach, Francois; Wiklund, Olov

2015-01-01

Statin-associated muscle symptoms (SAMS) are one of the principal reasons for statin non-adherence and/or discontinuation, contributing to adverse cardiovascular outcomes. This European Atherosclerosis Society (EAS) Consensus Panel overviews current understanding of the pathophysiology of statin-associated myopathy, and provides guidance for diagnosis and management of SAMS. Statin-associated myopathy, with significant elevation of serum creatine kinase (CK), is a rare but serious side effect of statins, affecting 1 per 1000 to 1 per 10 000 people on standard statin doses. Statin-associated muscle symptoms cover a broader range of clinical presentations, usually with normal or minimally elevated CK levels, with a prevalence of 7–29% in registries and observational studies. Preclinical studies show that statins decrease mitochondrial function, attenuate energy production, and alter muscle protein degradation, thereby providing a potential link between statins and muscle symptoms; controlled mechanistic and genetic studies in humans are necessary to further understanding. The Panel proposes to identify SAMS by symptoms typical of statin myalgia (i.e. muscle pain or aching) and their temporal association with discontinuation and response to repetitive statin re-challenge. In people with SAMS, the Panel recommends the use of a maximally tolerated statin dose combined with non-statin lipid-lowering therapies to attain recommended low-density lipoprotein cholesterol targets. The Panel recommends a structured work-up to identify individuals with clinically relevant SAMS generally to at least three different statins, so that they can be offered therapeutic regimens to satisfactorily address their cardiovascular risk. Further research into the underlying pathophysiological mechanisms may offer future therapeutic potential. PMID:25694464

2D NMR studies on muscle and cerebral metabolism in vivo

Energy Technology Data Exchange (ETDEWEB)

Gillet, B.; Doan, B.T.; Verre-Sebrie, C.; Fedeli, O.; Beloeil, J.C. (Centre National de la Recherche Scientifique (CNRS), 91 - Gif-sur-Yvette (France). Inst. de Chimie des Substances Naturelles); Peres, M. (CERMA-CEV, 91 - Bretigny-sur-Orge (France)); Barrere, B.; Seylaz, J. (Paris-7 Univ., 75 (France)); Morin, S.; Koenig, J. (Bordeaux-1 Univ., 33 - Talence (France)); Sebille, A. (Faculte de Medecine Saint-Antoine, 75 - Paris (France))

1994-06-01

New developments in in vivo 2D[sup 1]H NMR spectroscopy now allow several metabolites, which are not resolved by 1D NMR to be assigned. This report describes the use of this technique to follow the time courses of changes in the concentration of metabolites in the rat brain during physiological and pathophysiological processes (hyperglycemia and hypoxia) and to compare the fatty acid components of normal and dystrophic mouse gastrocnemius muscle. (authors). 15 refs., 5 figs.

Intermittent pneumatic compression regulates expression of nitric oxide synthases in skeletal muscles.

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Tan, Xiangling; Qi, Wen-Ning; Gu, Xiaosong; Urbaniak, James R; Chen, Long-En

2006-01-01

This study investigated the effects of intermittent pneumatic compression (IPC) on expression of nitric oxide synthase (NOS) isoforms in compressed (anterior tibialis, AT) and uncompressed (cremaster muscles, CM) skeletal muscles. Following IPC application of 0.5, 1, and 5h on both legs of rats, the endothelial NOS (eNOS) mRNA expression was significantly up-regulated to 1.2-, 1.8, and 2.7-fold from normal, respectively, in both AT and CM, and protein expression increased more than 1.5-fold of normal at each time point. Similarly, neuronal NOS expression was up-regulated, but to a lesser degree. In contrast, inducible NOS expression was significantly and time-dependently down-regulated in both muscles. After IPC cessation, eNOS levels returned to normal in both AT and CM. The results confirm our hypothesis that IPC-induced vasodilation is mediated by regulating expression of NOS isoforms, in particular eNOS, in both compressed and uncompressed skeletal muscles. The results also suggest the importance of precisely characterizing expression of each NOS isoform in tissue pathophysiology.

Contribution of TMS and rTMS in the Understanding of the Pathophysiology and in the Treatment of Dystonia.

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Lozeron, Pierre; Poujois, Aurélia; Richard, Alexandra; Masmoudi, Sana; Meppiel, Elodie; Woimant, France; Kubis, Nathalie

2016-01-01

Dystonias represent a heterogeneous group of movement disorders responsible for sustained muscle contraction, abnormal postures, and muscle twists. It can affect focal or segmental body parts or be generalized. Primary dystonia is the most common form of dystonia but it can also be secondary to metabolic or structural dysfunction, the consequence of a drug's side-effect or of genetic origin. The pathophysiology is still not elucidated. Based on lesion studies, dystonia has been regarded as a pure motor dysfunction of the basal ganglia loop. However, basal ganglia lesions do not consistently produce dystonia and lesions outside basal ganglia can lead to dystonia; mild sensory abnormalities have been reported in the dystonic limb and imaging studies have shown involvement of multiple other brain regions including the cerebellum and the cerebral motor, premotor and sensorimotor cortices. Transcranial magnetic stimulation (TMS) is a non-invasive technique of brain stimulation with a magnetic field applied over the cortex allowing investigation of cortical excitability. Hyperexcitability of contralateral motor cortex has been suggested to be the trigger of focal dystonia. High or low frequency repetitive TMS (rTMS) can induce excitatory or inhibitory lasting effects beyond the time of stimulation and protocols have been developed having either a positive or a negative effect on cortical excitability and associated with prevention of cell death, γ-aminobutyric acid (GABA) interneurons mediated inhibition and brain-derived neurotrophic factor modulation. rTMS studies as a therapeutic strategy of dystonia have been conducted to modulate the cerebral areas involved in the disease. Especially, when applied on the contralateral (pre)-motor cortex or supplementary motor area of brains of small cohorts of dystonic patients, rTMS has shown a beneficial transient clinical effect in association with restrained motor cortex excitability. TMS is currently a valuable tool to improve

Contribution of TMS and rTMS in the understanding of the pathophysiology and in the treatment of dystonia.

Directory of Open Access Journals (Sweden)

Pierre Lozeron

2016-11-01

Full Text Available Dystonias represent a heterogeneous group of movement disorders responsible for sustained muscle contraction, abnormal postures and muscle twists. It can affect focal or segmental body parts or be generalized. Primary dystonia is the most common form of dystonia but it can also be secondary to metabolic or structural dysfunction, the consequence of a drug’s side-effect or of genetic origin. The pathophysiology is still not elucidated. Based on lesion studies, dystonia has been regarded as a pure motor dysfunction of the basal ganglia loop. However, basal ganglia lesions do not consistently produce dystonia and lesions outside basal ganglia can lead to dystonia; mild sensory abnormalities have been reported in the dystonic limb and imaging studies have shown involvement of multiple other brain regions including the cerebellum and the cerebral motor, premotor and sensorimotor cortices. Transcranial magnetic stimulation (TMS is a non-invasive technique of brain stimulation with a magnetic field applied over the cortex allowing investigation of cortical excitability. Hyperexcitability of contralateral motor cortex has been suggested to be the trigger of focal dystonia. High or low frequency repetitive TMS (rTMS can induce excitatory or inhibitory lasting effects beyond the time of stimulation and protocols have been developed having either a positive or a negative effect on cortical excitability and associated with prevention of cell death, γ-aminobutyric acid (GABA interneurons mediated inhibition and brain-derived neurotrophic factor (BDNF modulation. rTMS studies as a therapeutic strategy of dystonia have been conducted to modulate the cerebral areas involved in the disease. Especially, when applied on the contralateral (pre-motor cortex or supplementary motor area of brains of small cohorts of dystonic patients, rTMS has shown a beneficial transient clinical effect in association with restrained motor cortex excitability. TMS is currently a

Myocardial fibrosis burden predicts left ventricular ejection fraction and is associated with age and steroid treatment duration in duchenne muscular dystrophy.

Science.gov (United States)

Tandon, Animesh; Villa, Chet R; Hor, Kan N; Jefferies, John L; Gao, Zhiqian; Towbin, Jeffrey A; Wong, Brenda L; Mazur, Wojciech; Fleck, Robert J; Sticka, Joshua J; Benson, D Woodrow; Taylor, Michael D

2015-03-26

Patients with Duchenne muscular dystrophy exhibit progressive cardiac and skeletal muscle dysfunction. Based on prior data, cardiac dysfunction in Duchenne muscular dystrophy patients may be influenced by myocardial fibrosis and steroid therapy. We examined the longitudinal relationship of myocardial fibrosis and ventricular dysfunction using cardiac magnetic resonance in a large Duchenne muscular dystrophy cohort. We reviewed 465 serial cardiac magnetic resonance studies (98 Duchenne muscular dystrophy patients with ≥4 cardiac magnetic resonance studies) for left ventricular ejection fraction (LVEF) and presence of late gadolinium enhancement (LGE), a marker for myocardial fibrosis. LVEF was modeled by examining LGE status, myocardial fibrosis burden (as assessed by the number of LGE-positive left ventricular segments), patient age, and steroid treatment duration. An age-only model demonstrated that LVEF declined 0.58 ± 0.10% per year. In patients with both LGE-negative and LGE-positive studies (n=51), LVEF did not decline significantly over time if LGE was absent but declined 2.2 ± 0.31% per year when LGE was present. Univariate modeling showed significant associations between LVEF and steroid treatment duration, presence of LGE, and number of LGE-positive left ventricular segments; multivariate modeling showed that LVEF declined by 0.93 ± 0.09% for each LGE-positive left ventricular segment, whereas age and steroid treatment duration were not significant. The number of LGE-positive left ventricular segments increased with age, and longer steroid treatment duration was associated with lower age-related increases. Progressive myocardial fibrosis, as detected by LGE, was strongly correlated with the LVEF decline in Duchenne muscular dystrophy patients. Longer steroid treatment duration was associated with a lower age-related increase in myocardial fibrosis burden. © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley

Genetics Home Reference: arrhythmogenic right ventricular cardiomyopathy

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... cardiomyopathy Merck Manual Consumer Version: Cardiomyopathy Merck Manual Consumer Version: Overview of Abnormal Heart Rhythms Orphanet: Arrhythmogenic right ventricular cardiomyopathy Orphanet: Familial isolated arrhythmogenic right ventricular ...

Left Ventricular Assist Devices

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Khuansiri Narajeenron

2017-04-01

Full Text Available Audience: The audience for this classic team-based learning (cTBL session is emergency medicine residents, faculty, and students; although this topic is applicable to internal medicine and family medicine residents. Introduction: A left ventricular assist device (LVAD is a mechanical circulatory support device that can be placed in critically-ill patients who have poor left ventricular function. After LVAD implantation, patients have improved quality of life.1 The number of LVAD patients worldwide continues to rise. Left-ventricular assist device patients may present to the emergency department (ED with severe, life-threatening conditions. It is essential that emergency physicians have a good understanding of LVADs and their complications. Objectives: Upon completion of this cTBL module, the learner will be able to: 1 Properly assess LVAD patients’ circulatory status; 2 appropriately resuscitate LVAD patients; 3 identify common LVAD complications; 4 evaluate and appropriately manage patients with LVAD malfunctions. Method: The method for this didactic session is cTBL.

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

International Nuclear Information System (INIS)

Narita, Michihiro; Kurihara, Tadashi

2000-01-01

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

Obesity: Pathophysiology and Intervention

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Yi Zhang

2014-11-01

Full Text Available Obesity presents a major health hazard of the 21st century. It promotes co-morbid diseases such as heart disease, type 2 diabetes, obstructive sleep apnea, certain types of cancer, and osteoarthritis. Excessive energy intake, physical inactivity, and genetic susceptibility are main causal factors for obesity, while gene mutations, endocrine disorders, medication, or psychiatric illnesses may be underlying causes in some cases. The development and maintenance of obesity may involve central pathophysiological mechanisms such as impaired brain circuit regulation and neuroendocrine hormone dysfunction. Dieting and physical exercise offer the mainstays of obesity treatment, and anti-obesity drugs may be taken in conjunction to reduce appetite or fat absorption. Bariatric surgeries may be performed in overtly obese patients to lessen stomach volume and nutrient absorption, and induce faster satiety. This review provides a summary of literature on the pathophysiological studies of obesity and discusses relevant therapeutic strategies for managing obesity.

The influence of type 2 diabetes and gender on ventricular repolarization dispersion in patients with sub-clinic left ventricular diastolic dysfunction.

Science.gov (United States)

Jani, Ylber; Kamberi, Ahmet; Xhunga, Sotir; Pocesta, Bekim; Ferati, Fatmir; Lala, Dali; Zeqiri, Agim; Rexhepi, Atila

2015-01-01

To assess the influence of type 2 DM and gender, on the QT dispersion, Tpeak-Tend dispersion of ventricular repolarization, in patients with sub-clinic left ventricular diastolic dysfunction of the heart. QT dispersion, that reflects spatial inhomogeneity in ventricular repolarization, Tpeak-Tend dispersion, this on the other hand reflects transmural inhomogeneity in ventricular repolarization, that is increased in an early stage of cardiomyopathy, and in patients with left ventricular diastolic dysfunction, as well. The left ventricular diastolic dysfunction, a basic characteristic of diabetic heart disease (diabetic cardiomyopathy), that developes earlier than systolic dysfunction, suggests that diastolic markers might be sensitive for early cardiac injury. It is also demonstrated that gender has complex influence on indices of myocardial repolarization abnormalities such as QT interval and QT dispersion. We performed an observational study including 300 diabetic patients with similar epidemiological-demographic characteristics recruited in our institution from May 2009 to July 2014, divided into two groups. Demographic and laboratory echocardiographic data were obtained, twelve lead resting electrocardiography, QT, QTc, Tpeak-Tend-intervals and dispersion, were determined manually, and were compared between various groups. For statistical analysis a t-test, X(2) test, and logistic regression are used according to the type of variables. A p value <0.05 was considered statistically significant for a confidence interval of 95%. QTc max. interval, QTc dispersion and Tpeak-Tend dispersion, were significantly higher in diabetic group with subclinical LV (left ventricular) diastolic dysfunction, than in diabetic group with normal left ventricular diastolic function (445.24±14.7 ms vs. 433.55±14.4 ms, P<0.000; 44.98±18.78 ms vs. 32.05±17.9 ms, P<0.000; 32.60±1.6 ms vs. 17.46±2.0 ms, P<0.02. Prolonged QTc max. interval was found in 33% of patients, indiabetic group

Biochemical and muscle studies in patients with acute onset post-viral fatigue syndrome.

OpenAIRE

Preedy, V R; Smith, D G; Salisbury, J R; Peters, T J

1993-01-01

AIMS--To investigate in detail various biochemical and pathophysiological indices of muscle pathology in acute onset post-viral fatigue syndrome (PVFS). METHODS--Twenty three patients with PVFS (of mean duration 4.6 years) were subjected to needle biopsy for histomorphometry and total RNA contents. Plasma analysis included serology and creatine kinase activities. Indices of whole body mass were also measured--namely, whole body potassium content and plasma carnosinase activities. RESULTS--Abo...

A Prospective Study of Ripple Mapping the Post-Infarct Ventricular Scar to Guide Substrate Ablation for Ventricular Tachycardia.

Science.gov (United States)

Luther, Vishal; Linton, Nick W F; Jamil-Copley, Shahnaz; Koa-Wing, Michael; Lim, Phang Boon; Qureshi, Norman; Ng, Fu Siong; Hayat, Sajad; Whinnett, Zachary; Davies, D Wyn; Peters, Nicholas S; Kanagaratnam, Prapa

2016-06-01

Post-infarct ventricular tachycardia is associated with channels of surviving myocardium within scar characterized by fractionated and low-amplitude signals usually occurring late during sinus rhythm. Conventional automated algorithms for 3-dimensional electro-anatomic mapping cannot differentiate the delayed local signal of conduction within the scar from the initial far-field signal generated by surrounding healthy tissue. Ripple mapping displays every deflection of an electrogram, thereby providing fully informative activation sequences. We prospectively used CARTO-based ripple maps to identify conducting channels as a target for ablation. High-density bipolar left ventricular endocardial electrograms were collected using CARTO3v4 in sinus rhythm or ventricular pacing and reviewed for ripple mapping conducting channel identification. Fifteen consecutive patients (median age 68 years, left ventricular ejection fraction 30%) were studied (6 month preprocedural implantable cardioverter defibrillator therapies: median 19 ATP events [Q1-Q3=4-93] and 1 shock [Q1-Q3=0-3]). Scar (ripple mapping conducting channels were seen within each scar (length 60 mm; initial component 0.44 mV; delayed component 0.20 mV; conduction 55 cm/s). Ablation was performed along all identified ripple mapping conducting channels (median 18 lesions) and any presumed interconnected late-activating sites (median 6 lesions; Q1-Q3=2-12). The diastolic isthmus in ventricular tachycardia was mapped in 3 patients and colocated within the ripple mapping conducting channels identified. Ventricular tachycardia was noninducible in 85% of patients post ablation, and 71% remain free of ventricular tachycardia recurrence at 6-month median follow-up. Ripple mapping can be used to identify conduction channels within scar to guide functional substrate ablation. © 2016 American Heart Association, Inc.

Pathophysiology, Evaluation, and Treatment of Bloating

Science.gov (United States)

Gabbard, Scott L.; Crowell, Michael D.

2011-01-01

Abdominal bloating is commonly reported by men and women of all ages. Bloating occurs in nearly all patients with irritable bowel syndrome, and it also occurs in patients with other functional and organic disorders. Bloating is frequently disturbing to patients and frustrating to clinicians, as effective treatments are limited and are not universally successful. Although the terms bloating and abdominal distention are often used interchangeably, these symptoms likely involve different pathophysiologic processes, both of which are still not completely understood. The goal of this paper is to review the pathophysiology, evaluation, and treatment of bloating and abdominal distention. PMID:22298969

follow-up of patients with arrhythmogenic right ventricular

African Journals Online (AJOL)

was sudden, 1 patient died due to left ventricular failure, and ... Arrhythmogenic right ventricular cardiomyopathy/ dysplasia .... hypertension and from atrial fibrillation that developed 2.4 .... of left ventricular function was global without regional ..... 99mTc he brain si before a acid (G minute his sem next 3 - his sem showed.

Modeling Cerebrovascular Pathophysiology in Amyloid-β Metabolism using Neural-Crest-Derived Smooth Muscle Cells

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Christine Cheung

2014-10-01

Full Text Available Summary: There is growing recognition of cerebrovascular contributions to neurodegenerative diseases. In the walls of cerebral arteries, amyloid-beta (Aβ accumulation is evident in a majority of aged people and patients with cerebral amyloid angiopathy. Here, we leverage human pluripotent stem cells to generate vascular smooth muscle cells (SMCs from neural crest progenitors, recapitulating brain-vasculature-specific attributes of Aβ metabolism. We confirm that the lipoprotein receptor, LRP1, functions in our neural-crest-derived SMCs to mediate Aβ uptake and intracellular lysosomal degradation. Hypoxia significantly compromises the contribution of SMCs to Aβ clearance by suppressing LRP1 expression. This enabled us to develop an assay of Aβ uptake by using the neural crest-derived SMCs with hypoxia as a stress paradigm. We then tested several vascular protective compounds in a high-throughput format, demonstrating the value of stem-cell-based phenotypic screening for novel therapeutics and drug repurposing, aimed at alleviating amyloid burden. : The contribution of blood vessel pathologies to neurodegenerative disorders is relatively neglected, partly due to inadequate human tissues for research. By using human stem cells, Cheung et al. establish a method of generating vascular smooth muscle cells (SMCs from neural crest progenitors, the primary precursors that give rise to brain blood vessels. These stem-cell-derived SMCs display defective amyloid processing under chronic hypoxia, a phenomenon well documented in the cerebral vasculatures of aged people and patients with Alzheimer’s disease.

Remodelado ventricular y cirugía

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Ignacio Moriones

2008-01-01

Se han diseñado anillos mitrales como el de Carpentier- McCarthy-Adams (IMR ETlogix™ para pacientes isquémicos, o el Edwards-Geoform™ en miocardiopatías. La asistencia ventricular puede conseguir en determinados casos recuperación permanente del volumen de la cavidad y función ventricular, particularmente en miocarditis y determinadas miocardiopatías. Paralelamente, se han iniciado experiencias con el sistema de contención CorCap o el sistema Myosplint. Finalmente, la actuación sobre las valvulopatías y la revascularización favorecen la restauración ventricular.

Relationship of left ventricular systolic function to persistence or development of electrocardiographic left ventricular hypertrophy in hypertensive patients

DEFF Research Database (Denmark)

Okin, Peter M; Wachtell, Kristian; Gerdts, Eva

2014-01-01

left ventricular systolic function in patients with new or persistent ECG LVH. METHODS: Baseline and year-3 ECG LVH and left ventricular midwall shortening (MWS) were examined in 725 hypertensive patients in the Losartan Intervention For Endpoint reduction in hypertension (LIFE) echocardiographic...... 1.03-3.50, P = 0.040) at year 3. CONCLUSION: Persistence or development of new ECG LVH during antihypertensive therapy is associated with an increased risk of left ventricular systolic dysfunction after 3 years' follow-up. These findings provide insight into a possible mechanism by which changes......BACKGROUND: Persistence or development of ECG left ventricular hypertrophy (LVH) by Cornell product criteria is associated with an increased risk of developing heart failure compared with regression or continued absence of LVH. We postulated that this association might be in part mediated via worse...

Fibroblasts and the extracellular matrix in right ventricular disease.

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Frangogiannis, Nikolaos G

2017-10-01

Right ventricular failure predicts adverse outcome in patients with pulmonary hypertension (PH), and in subjects with left ventricular heart failure and is associated with interstitial fibrosis. This review manuscript discusses the cellular effectors and molecular mechanisms implicated in right ventricular fibrosis. The right ventricular interstitium contains vascular cells, fibroblasts, and immune cells, enmeshed in a collagen-based matrix. Right ventricular pressure overload in PH is associated with the expansion of the fibroblast population, myofibroblast activation, and secretion of extracellular matrix proteins. Mechanosensitive transduction of adrenergic signalling and stimulation of the renin-angiotensin-aldosterone cascade trigger the activation of right ventricular fibroblasts. Inflammatory cytokines and chemokines may contribute to expansion and activation of macrophages that may serve as a source of fibrogenic growth factors, such as transforming growth factor (TGF)-β. Endothelin-1, TGF-βs, and matricellular proteins co-operate to activate cardiac myofibroblasts, and promote synthesis of matrix proteins. In comparison with the left ventricle, the RV tolerates well volume overload and ischemia; whether the right ventricular interstitial cells and matrix are implicated in these favourable responses remains unknown. Expansion of fibroblasts and extracellular matrix protein deposition are prominent features of arrhythmogenic right ventricular cardiomyopathies and may be implicated in the pathogenesis of arrhythmic events. Prevailing conceptual paradigms on right ventricular remodelling are based on extrapolation of findings in models of left ventricular injury. Considering the unique embryologic, morphological, and physiologic properties of the RV and the clinical significance of right ventricular failure, there is a need further to dissect RV-specific mechanisms of fibrosis and interstitial remodelling. Published on behalf of the European Society of

Free and conjugated dopamine in human ventricular fluid

International Nuclear Information System (INIS)

Sharpless, N.S.; Thal, L.J.; Wolfson, L.I.; Tabaddor, K.; Tyce, G.M.; Waltz, J.M.

1981-01-01

Free dopamine and an acid hydrolyzable conjugate of dopamine were measured in human ventricular fluid specimens with a radioenzymatic assay and by high performance liquid chromatography (HPLC) with electrochemical detection. Only trace amounts of free norepinephrine and dopamine were detected in ventricular fluid from patients with movement disorders. When the ventricular fluid was hydrolyzed by heating in HClO 4 or by lyophilization in dilute HClO 4 , however, a substantial amount of free dopamine was released. Values for free plus conjugated dopamine in ventricular fluid from patients who had never taken L-DOPA ranged from 139 to 340 pg/ml when determined by HPLC and from 223 to 428 pg/ml when measured radioenzymatically. The correlation coefficient for values obtained by the two methods in the same sample of CSF was 0.94 (P<0.001). Patients who had been treated with L-DOPA had higher levels of conjugated dopamine in their ventricular CSF which correlated inversely with the time between the last dose of L-DOPA and withdrawal of the ventricular fluid. Additionally, one patient with acute cerebral trauma had elevated levels of free norepinephrine and both free and conjugated dopamine in his ventricular fluid. Conjugation may be an important inactivation pathway for released dopamine in man. (Auth.)

Left ventricular apical ballooning syndrome

International Nuclear Information System (INIS)

Rahman, N.; Tai, J.; Soofi, A.

2007-01-01

The transient left ventricular apical ballooning syndrome, also known as Takotsubo cardiomyopathy, is characterized by transient left ventricular dysfunction in the absence of obstructive epicardial coronary disease. Although the syndrome has been reported in Japan since 1990, it is rare in other regions. Rapid recognition of the syndrome can modify the diagnostic and therapeutic attitude i.e. avoiding thrombolysis and performing catheterization in the acute phase. (author)

Parasympathetic neurons in the cranial medial ventricular fat pad on the dog heart selectively decrease ventricular contractility.

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Dickerson, L W; Rodak, D J; Fleming, T J; Gatti, P J; Massari, V J; McKenzie, J C; Gillis, R A

1998-05-28

We hypothesized that selective control of ventricular contractility might be mediated by postganglionic parasympathetic neurons in the cranial medial ventricular (CMV) ganglion plexus located in a fat pad at the base of the aorta. Sinus rate, atrioventricular (AV) conduction (ventricular rate during atrial pacing), and left ventricular contractile force (LV dP/dt during right ventricular pacing) were measured in eight chloralose-anesthetized dogs both before and during bilateral cervical vagus stimulation (20-30 V, 0.5 ms pulses, 15-20 Hz). Seven of these dogs were tested under beta-adrenergic blockade (propranolol, 0.8 mg kg(-1) i.v.). Control responses included sinus node bradycardia or arrest during spontaneous rhythm, high grade AV block or complete heart block, and a 30% decrease in contractility from 2118 +/- 186 to 1526 +/- 187 mm Hg s(-1) (P 0.05) decrease in contractility but still elicited the same degree of sinus bradycardia and AV block (N = 8, P < 0.05). Five dogs were re-tested 3 h after trimethaphan fat pad injection, at which time blockade of vagally-induced negative inotropy was partially reversed, as vagal stimulation decreased LV dP/dt by 19%. The same dose of trimethaphan given either locally into other fat pads (PVFP or IVC-ILA) or systemically (i.v.) had no effect on vagally-induced negative inotropy. Thus, parasympathetic ganglia located in the CMV fat pad mediated a decrease in ventricular contractility during vagal stimulation. Blockade of the CMV fat pad had no effect on vagally-mediated slowing of sinus rate or AV conduction.

More than a bystander: the contributions of intrinsic skeletal muscle defects in motor neuron diseases.

Science.gov (United States)

Boyer, Justin G; Ferrier, Andrew; Kothary, Rashmi

2013-12-18

Spinal muscular atrophy (SMA), amyotrophic lateral sclerosis (ALS), and spinal-bulbar muscular atrophy (SBMA) are devastating diseases characterized by the degeneration of motor neurons. Although the molecular causes underlying these diseases differ, recent findings have highlighted the contribution of intrinsic skeletal muscle defects in motor neuron diseases. The use of cell culture and animal models has led to the important finding that muscle defects occur prior to and independently of motor neuron degeneration in motor neuron diseases. In SMA for instance, the muscle specific requirements of the SMA disease-causing gene have been demonstrated by a series of genetic rescue experiments in SMA models. Conditional ALS mouse models expressing a muscle specific mutant SOD1 gene develop atrophy and muscle degeneration in the absence of motor neuron pathology. Treating SBMA mice by over-expressing IGF-1 in a skeletal muscle-specific manner attenuates disease severity and improves motor neuron pathology. In the present review, we provide an in depth description of muscle intrinsic defects, and discuss how they impact muscle function in these diseases. Furthermore, we discuss muscle-specific therapeutic strategies used to treat animal models of SMA, ALS, and SBMA. The study of intrinsic skeletal muscle defects is crucial for the understanding of the pathophysiology of these diseases and will open new therapeutic options for the treatment of motor neuron diseases.

Skeletal muscle injury induced by a pneumatic tourniquet: an enzyme- and immunohistochemical study in rabbits.

Science.gov (United States)

Pedowitz, R A; Fridén, J; Thornell, L E

1992-03-01

The pathophysiology of skeletal muscle injury induced by compression beneath pneumatic tourniquets is poorly understood. Tourniquet hemostasis was induced in rabbit hindlimbs for 2 hr with a cuff inflation pressure of either 125 mm Hg (n = 5) or 350 mm Hg (n = 5). Skeletal muscle biopsies, taken 2 days later from tissue beneath and distal to the tourniquet, were frozen and analyzed using enzyme- and immunohistochemical techniques. In the 350 mm Hg tourniquet group, four of 10 thigh muscle samples demonstrated significant regional necrosis (mean 37.3% of the total cross-sectional area). Regional necrosis was not observed in thigh muscles of the 125 mm Hg tourniquet group or in any of the ischemic leg muscles. A topographic pattern of necrosis consistent with the arterial distribution of skeletal muscle suggested pathogenic events during the reperfusion period, such as granulocyte-mediated superoxide radical formation. Extremely large and rounded fibers (histochemically identified as Type IIB fibers) were observed in compressed thigh muscles, indicating differential fiber sensitivity to tourniquet compression and ischemia. The present study demonstrated significant skeletal muscle necrosis after a 2 hr tourniquet applied at a clinically relevant cuff inflation pressure. Recent studies of systemic changes associated with limb "ischemia" should be reassessed in consideration of the confounding effects of tissue compression induced beneath pneumatic tourniquets.

Targeting deregulated AMPK/mTORC1 pathways improves muscle function in myotonic dystrophy type I.

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Brockhoff, Marielle; Rion, Nathalie; Chojnowska, Kathrin; Wiktorowicz, Tatiana; Eickhorst, Christopher; Erne, Beat; Frank, Stephan; Angelini, Corrado; Furling, Denis; Rüegg, Markus A; Sinnreich, Michael; Castets, Perrine

2017-02-01

Myotonic dystrophy type I (DM1) is a disabling multisystemic disease that predominantly affects skeletal muscle. It is caused by expanded CTG repeats in the 3'-UTR of the dystrophia myotonica protein kinase (DMPK) gene. RNA hairpins formed by elongated DMPK transcripts sequester RNA-binding proteins, leading to mis-splicing of numerous pre-mRNAs. Here, we have investigated whether DM1-associated muscle pathology is related to deregulation of central metabolic pathways, which may identify potential therapeutic targets for the disease. In a well-characterized mouse model for DM1 (HSALR mice), activation of AMPK signaling in muscle was impaired under starved conditions, while mTORC1 signaling remained active. In parallel, autophagic flux was perturbed in HSALR muscle and in cultured human DM1 myotubes. Pharmacological approaches targeting AMPK/mTORC1 signaling greatly ameliorated muscle function in HSALR mice. AICAR, an AMPK activator, led to a strong reduction of myotonia, which was accompanied by partial correction of misregulated alternative splicing. Rapamycin, an mTORC1 inhibitor, improved muscle relaxation and increased muscle force in HSALR mice without affecting splicing. These findings highlight the involvement of AMPK/mTORC1 deregulation in DM1 muscle pathophysiology and may open potential avenues for the treatment of this disease.

Value of the Electrocardiogram as a Predictor of Right Ventricular Dysfunction in Patients With Chronic Right Ventricular Volume Overload.

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Alonso, Pau; Andrés, Ana; Rueda, Joaquín; Buendía, Francisco; Igual, Begoña; Rodríguez, María; Osa, Ana; Arnau, Miguel A; Salvador, Antonio

2015-05-01

Pulmonary regurgitation is a common complication in patients with repaired tetralogy of Fallot or congenital pulmonary stenosis. Electrocardiographic variables have been correlated with parameters used to evaluate right ventricular function. We aimed to analyze the diagnostic value of the width and fragmentation of the electrocardiogram in the identification of patients with right ventricular dysfunction and/or dilation. We selected 107 consecutive patients diagnosed with severe pulmonary insufficiency after repair of pulmonary stenosis or tetralogy of Fallot. The tests included electrocardiography, echocardiography, and magnetic resonance. Each electrocardiogram was analyzed manually to measure QRS duration. We defined QRS fragmentation as the presence of low-voltage waves in the terminal portion of the QRS complex in at least 2 contiguous leads. We found a significant negative correlation between QRS width and right ventricular function, as well as a positive correlation with right ventricular volume. The receiver operating characteristic curve indicated a cut-off point for QRS width of 140ms, which showed good sensitivity for a diagnosis of right ventricular dilation (> 80%) and dysfunction (> 95%). In logistic regression models, a QRS duration > 140ms was found to be the only independent predictor of right ventricular dilation and dysfunction. Electrocardiography is a rapid, widely available, and reproducible tool. QRS width constitutes an independent predictor of the presence of right ventricular dilation and dysfunction. This study is the first to provide a cutoff value for QRS width to screen for right ventricle involvement. Copyright © 2014 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Lone ventricular cardiomyopathy,

African Journals Online (AJOL)

... (I) cardiac catheterisation, including coronary arteriography and pulmonary ... described existence of lone ventricular idiopathic ... spectrum of classic idiopathic dilated cardiomyopathy. ... endomyocardial fibrosis, and from discussions at an.

Ventricular filling slows epicardial conduction and increases action potential duration in an optical mapping study of the isolated rabbit heart

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Sung, Derrick; Mills, Robert W.; Schettler, Jan; Narayan, Sanjiv M.; Omens, Jeffrey H.; McCulloch, Andrew D.; McCullough, A. D. (Principal Investigator)

2003-01-01

INTRODUCTION: Mechanical stimulation can induce electrophysiologic changes in cardiac myocytes, but how mechanoelectric feedback in the intact heart affects action potential propagation remains unclear. METHODS AND RESULTS: Changes in action potential propagation and repolarization with increased left ventricular end-diastolic pressure from 0 to 30 mmHg were investigated using optical mapping in isolated perfused rabbit hearts. With respect to 0 mmHg, epicardial strain at 30 mmHg in the anterior left ventricle averaged 0.040 +/- 0.004 in the muscle fiber direction and 0.032 +/- 0.006 in the cross-fiber direction. An increase in ventricular loading increased average epicardial activation time by 25%+/- 3% (P action potential duration at 20% repolarization (APD20) but did at 80% repolarization (APD80), from 179 +/- 7 msec to 207 +/- 5 msec (P action potential duration by a load-dependent mechanism that may not involve stretch-activated channels.

Relação entre Fibrose e Arritmias Ventriculares na Cardiopatia Chagásica sem Disfunção Ventricular

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Eduardo Marinho Tassi

2014-06-01

Full Text Available Fundamento: Pacientes com doença de Chagas com alteração segmentar apresentam pior prognóstico independentemente da fração de ejeção ventricular esquerda. A ressonância magnética cardíaca é atualmente o melhor método para detecção de alteração segmentar e para avaliação de fibrose miocárdica. Objetivo: Quantificar a fibrose, por meio do realce tardio, pela ressonância magnética cardíaca, em pacientes com doença de Chagas com fração de ejeção ventricular esquerda preservada ou minimamente comprometida (> 45% e detectar padrões de dependência entre fibrose, alteração segmentar e fração de ejeção ventricular esquerda na presença de arritmia ventricular. Métodos: Foram realizados eletrocardiograma, teste ergométrico, Holter e ressonância magnética cardíaca em 61 pacientes, separados em três grupos: (1 eletrocardiograma normal e ressonância magnética cardíaca sem alteração segmentar; (2 eletrocardiograma alterado e ressonância magnética cardíaca sem alteração segmentar; e (3 ressonância magnética cardíaca com alteração segmentar independentemente de alteração no eletrocardiograma. Resultados: O número de pacientes com arritmia ventricular em relação ao número total de pacientes em cada grupo, a porcentagem de fibrose e a fração de ejeção ventricular esquerda foram, respectivamente: no primeiro grupo, 4/26, 0,74% e 74,34%; no segundo grupo, 4/16, 3,96% e 68,5%; e no terceiro grupo, 11/19, 14,07% e 55,59%. Arritmia ventricular foi encontrada em 31,1% dos pacientes. Aqueles com e sem arritmia ventricular apresentaram fração de ejeção ventricular esquerda média de 59,87% e 70,18%, respectivamente, e fibrose de 11,03% e 3,01%, respectivamente. Das variáveis alteração segmentar, grupos, idade, fração de ejeção ventricular esquerda e fibrose, a última foi a única significativa para a presença de arritmia ventricular, com ponto de corte de 11,78% para massa fibrosada (p < 0

Three dimensional endo-cardiovascular volume-rendered cine computed tomography of isolated left ventricular apical hypoplasia; A case report and literature review

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Hong, Sun Hwa; Kim, Yang Min; Lee, Hyun Jong [Sejong General Hospital, Bucheon (Korea, Republic of)

2016-02-15

We report multidetector computed tomography (MDCT) and cardiac magnetic resonance (CMR) findings of a 34-year-old female with isolated left ventricular apical hypoplasia. The MDCT and CMR scans displayed a spherical left ventricle (LV) with extensive fatty infiltration within the myocardium at the apex, interventricular septum and inferior wall, anteroapical origin of the papillary muscle, right ventricle wrapping around the deficient LV apex, and impaired systolic function. MDCT visualized morphologic and also functional findings of this unique cardiomyopathy.

The effect of heart failure and left ventricular assist device treatment on right ventricular mechanics: a computational study.

Science.gov (United States)

Park, Jun I K; Heikhmakhtiar, Aulia Khamas; Kim, Chang Hyun; Kim, Yoo Seok; Choi, Seong Wook; Song, Kwang Soup; Lim, Ki Moo

2018-05-22

Although it is important to analyze the hemodynamic factors related to the right ventricle (RV) after left ventricular assist device (LVAD) implantation, previous studies have focused only on the alteration of the ventricular shape and lack quantitative analysis of the various hemodynamic parameters. Therefore, we quantitatively analyzed various hemodynamic parameters related to the RV under normal, heart failure (HF), and HF incorporated with continuous flow LVAD therapy by using a computational model. In this study, we combined a three-dimensional finite element electromechanical model of ventricles, which is based on human ventricular morphology captured by magnetic resonance imaging (MRI) with a lumped model of the circulatory system and continuous flow LVAD function in order to construct an integrated model of an LVAD implanted-cardiovascular system. To induce systolic dysfunction, the magnitude of the calcium transient function under HF condition was reduced to 70% of the normal value, and the time constant was reduced by 30% of the normal value. Under the HF condition, the left ventricular end systolic pressure decreased, the left ventricular end diastolic pressure increased, and the pressure in the right atrium (RA), RV, and pulmonary artery (PA) increased compared with the normal condition. The LVAD therapy decreased the end-systolic pressure of the LV by 41%, RA by 29%, RV by 53%, and PA by 71%, but increased the right ventricular ejection fraction by 52% and cardiac output by 40%, while the stroke work was reduced by 67% compared with the HF condition without LVAD. The end-systolic ventricular tension and strain decreased with the LVAD treatment. LVAD enhances CO and mechanical unloading of the LV as well as those of the RV and prevents pulmonary hypertension which can be induced by HF.

Echocardiographic left ventricular masses in distance runners and weight lifters

Science.gov (United States)

Longhurst, J. C.; Gonyea, W. J.; Mitchell, J. H.; Kelly, A. R.

1980-01-01

The relationships of different forms of exercise training to left ventricular mass and body mass are investigated by echocardiographic studies of weight lifters, long-distance runners, and comparatively sized untrained control subjects. Left ventricular mass determinations by the Penn convention reveal increased absolute left ventricular masses in long-distance runners and competitive weight lifters with respect to controls matched for age, body weight, and body surface area, and a significant correlation between ventricular mass and lean body mass. When normalized to lean body mass, the ventricular masses of distance runners are found to be significantly higher than those of the other groups, suggesting that dynamic training elevates left ventricular mass compared to static training and no training, while static training increases ventricular mass only to the extent that lean body mass is increased.

THE CLINICAL-SIGNIFICANCE OF CORONARY ANATOMY IN POST-INFARCT PATIENTS WITH LATE SUSTAINED VENTRICULAR-TACHYCARDIA OR VENTRICULAR-FIBRILLATION

NARCIS (Netherlands)

WIESFELD, ACP; CRIJNS, HJGM; HILLEGE, HL; TUININGA, YS; LIE, KI

The role of ischaemia in post-infarct patients with ventricular tachyarrhythmias is not firmly established Using coronary angiography, 82 post-infarct patients with sustained ventricular tachycardia or fibrillation were subclassified into three groups. Fourteen patients (17%) had significant

Malignant ventricular tachycardia in acromegaly: a case report

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Zhe An

Full Text Available CONTEXT: In patients with acromegaly, cardiovascular complications are the main cause of death; sudden death has been associated with ventricular tachyarrhythmias. In other patients with life-threatening malignant ventricular tachyarrhythmias, surgical placement of an implantable cardioverter-defibrillator (ICD has proved highly effective in reducing sudden death rates. CASE REPORT: The present article reports the case of a 50-year-old male acromegalic patient who presented symptoms of syncope induced by ventricular tachycardia. An ICD was surgically implanted and a pituitary adenoma, which was responsible for the acromegaly, was completely removed in the same procedure. The surgery was successful and the ventricular arrhythmias were effectively terminated. During six months of follow-up, no documented arrhythmic episodes occurred. CONCLUSION: In patients with acromegaly, malignant ventricular tachyarrhythmia might be effectively controlled by implantation of an ICD and surgical removal of the pituitary adenoma.

Right ventricular function assessed by 2D strain analysis predicts ventricular arrhythmias and sudden cardiac death in patients after acute myocardial infarction

DEFF Research Database (Denmark)

Risum, Niels; Valeur, Nana; Søgaard, Peter

2017-01-01

Aims: Left ventricular function is a well-established predictor of malignant ventricular arrhythmias, but little is known about the importance of right ventricular (RV) function. The aim of this study was to investigate the importance of RV function for prediction of sudden cardiac death (SCD) or...

Serum miRNAs miR-23a, 206, and 499 as Potential Biomarkers for Skeletal Muscle Atrophy

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Fei Wang

2017-01-01

Full Text Available Muscle biopsy has long been expected to be replaced by noninvasive biomarkers with diagnostic value and prognostic applications for muscle atrophy. Growing evidence suggests that circulating microRNAs (miRNAs could act as biomarkers for numerous pathophysiological statuses. In the present study, our results showed that the serum levels of six muscle-specific miRNAs (miR-1/23a/133/206/208b/499 were all elevated in unloading induced mice. The medium levels of these six muscle-specific miRNAs were all elevated in starvation induced atrophic C2C12 myotubes. Moreover, the serum levels of miR-23a/206/499 were induced in participants after 45 days of head-down bed rest (HDBR. The levels of miR-23a/206/499 were positively correlated with the ratio of soleus volume loss in HDBR participants, indicating that they might represent the process of muscle loss. In conclusion, our results demonstrated that circulating miRNAs could serve as useful biochemical and molecular indicators for muscle atrophy diagnosis and disease progression.

Pathophysiology of Pulmonary Hypertension in Chronic Parenchymal Lung Disease.

Science.gov (United States)

Singh, Inderjit; Ma, Kevin Cong; Berlin, David Adam

2016-04-01

Pulmonary hypertension commonly complicates chronic obstructive pulmonary disease and interstitial lung disease. The association of chronic lung disease and pulmonary hypertension portends a worse prognosis. The pathophysiology of pulmonary hypertension differs in the presence or absence of lung disease. We describe the physiological determinants of the normal pulmonary circulation to better understand the pathophysiological factors implicated in chronic parenchymal lung disease-associated pulmonary hypertension. This review will focus on the pathophysiology of 3 forms of chronic lung disease-associated pulmonary hypertension: idiopathic pulmonary fibrosis, chronic obstructive pulmonary disease, and sarcoidosis. Copyright © 2016 Elsevier Inc. All rights reserved.

Ventricular repolarization measures for arrhythmic risk stratification

Institute of Scientific and Technical Information of China (English)

Francesco Monitillo; Marta Leone; Caterina Rizzo; Andrea Passantino; Massimo Iacoviello

2016-01-01

Ventricular repolarization is a complex electrical phenomenon which represents a crucial stage in electrical cardiac activity. It is expressed on the surface electrocardiogram by the interval between the start of the QRS complex and the end of the T wave or U wave(QT). Several physiological, pathological and iatrogenic factors can influence ventricular repolarization. It has been demonstrated that small perturbations in this process can be a potential trigger of malignant arrhythmias, therefore the analysis of ventricular repolarization represents an interesting tool to implement risk stratification of arrhythmic events in different clinical settings. The aim of this review is to critically revise the traditional methods of static analysis of ventricular repolarization as well as those for dynamic evaluation, their prognostic significance and the possible application in daily clinical practice.

The influence of type 2 diabetes and gender on ventricular repolarization dispersion in patients with sub-clinic left ventricular diastolic dysfunction

Science.gov (United States)

Jani, Ylber; Kamberi, Ahmet; Xhunga, Sotir; Pocesta, Bekim; Ferati, Fatmir; Lala, Dali; Zeqiri, Agim; Rexhepi, Atila

2015-01-01

Objective: To assess the influence of type 2 DM and gender, on the QT dispersion, Tpeak-Tend dispersion of ventricular repolarization, in patients with sub-clinic left ventricular diastolic dysfunction of the heart. Background: QT dispersion, that reflects spatial inhomogeneity in ventricular repolarization, Tpeak-Tend dispersion, this on the other hand reflects transmural inhomogeneity in ventricular repolarization, that is increased in an early stage of cardiomyopathy, and in patients with left ventricular diastolic dysfunction, as well. The left ventricular diastolic dysfunction, a basic characteristic of diabetic heart disease (diabetic cardiomyopathy), that developes earlier than systolic dysfunction, suggests that diastolic markers might be sensitive for early cardiac injury. It is also demonstrated that gender has complex influence on indices of myocardial repolarization abnormalities such as QT interval and QT dispersion. Material and methods: We performed an observational study including 300 diabetic patients with similar epidemiological-demographic characteristics recruited in our institution from May 2009 to July 2014, divided into two groups. Demographic and laboratory echocardiographic data were obtained, twelve lead resting electrocardiography, QT, QTc, Tpeak-Tend-intervals and dispersion, were determined manually, and were compared between various groups. For statistical analysis a t-test, X2 test, and logistic regression are used according to the type of variables. A p value <0.05 was considered statistically significant for a confidence interval of 95%. Results: QTc max. interval, QTc dispersion and Tpeak-Tend dispersion, were significantly higher in diabetic group with subclinical LV (left ventricular) diastolic dysfunction, than in diabetic group with normal left ventricular diastolic function (445.24±14.7 ms vs. 433.55±14.4 ms, P<0.000; 44.98±18.78 ms vs. 32.05±17.9 ms, P<0.000; 32.60±1.6 ms vs. 17.46±2.0 ms, P<0.02. Prolonged QTc max

An update on oxidative stress-mediated organ pathophysiology.

Science.gov (United States)

Rashid, Kahkashan; Sinha, Krishnendu; Sil, Parames C

2013-12-01

Exposure to environmental pollutants and drugs can result in pathophysiological situations in the body. Research in this area is essential as the knowledge on cellular survival and death would help in designing effective therapeutic strategies that are needed for the maintenance of the normal physiological functions of the body. In this regard, naturally occurring bio-molecules can be considered as potential therapeutic targets as they are normally available in commonly consumed foodstuffs and are thought to have minimum side effects. This review article describes the detailed mechanisms of oxidative stress-mediated organ pathophysiology and the ultimate fate of the cells either to survive or to undergo necrotic or apoptotic death. The mechanisms underlying the beneficial role of a number of naturally occurring bioactive molecules in oxidative stress-mediated organ pathophysiology have also been included in the review. The review provides useful information about the recent progress in understanding the mechanism(s) of various types of organ pathophysiology, the complex cross-talk between these pathways, as well as their modulation in stressed conditions. Additionally, it suggests possible therapeutic applications of a number of naturally occurring bioactive molecules in conditions involving oxidative stress. Copyright © 2013 Elsevier Ltd. All rights reserved.

Left ventricular mass in male adolescent athletes and non-athletes

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Erling David Kaunang

2014-10-01

Full Text Available Background Systematic exercise leads to increased left ventricular mass, which may be misleading in a differential diagnosis of heart disease in athletes (physiologic hypertrophy versus pathologic hypertrophy. T he cause of left ventricular hypertrophy is an important risk factor in the morbidity and mortality of cardiovascular diseases. Objective To compare left ventricular mass and left ventricular hypertrophy in male adolescent athletes and non-athletes. Methods We conducted a cross-sectional, analytic study, from September to December 2012 in male adolescents aged 15-18 years. The case group included athletes from the Bina Taruna Football Club Manado, while the control group included non-athlete adolescents. All subjects underwent history-taking, physical examinations and further supporting examinations. Left ventricular mass was measured by cardiovascular echocardiography (Esaote Mylab 4.0 and calculated based on a formula. Left ventricular hypertrophy was defined as left ventricular mass of > 134 g/m2 body surface area. Results Subjects' mean left ventricular masses were 359.69 (SD 188.4; 95%CI 283.58 to 435.81 grams in the athlete group and 173.04 (SD 50.69; 95%CI 152.56 to 103.51 grams in the non· athlete group, a statistically significant difference (P=0.0001. Ventricular hypertrophy was found 76.9% compared to 11.5% in  the non-athlete group (P= 0.0001. Conclusion Left ventricular mass in athletes is bigger than in non-athletes. In addition, left ventricular hypertrophy is more cornmon in male adolescent athletes than in non-athletes.

Detection of premature ventricular contractions on a ventricular electrocardiogram for patients with left ventricular assist devices.

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Park, Sung Min; Lee, Jin Hong; Choi, Seong Wook

2014-12-01

The ventricular electrocardiogram (v-ECG) was developed for long-term monitoring of heartbeats in patients with a left ventricular assist device (LVAD) and does not normally have the functionality necessary to detect additional heart irregularities that can progress to critical arrhythmias. Although the v-ECG has the benefits of physiological optimization and counterpulsation control, when abnormal heartbeats occur, the v-ECG does not show the distinct abnormal waveform that enables easy detection of an abnormal heartbeat among normal heartbeats on the conventional ECG. In this study, the v-ECGs of normal and abnormal heartbeats are compared with each other with respect to peak-to-peak voltage, area, and maximal slopes, and a new method to detect abnormal heartbeats is suggested. In a series of animal experiments with three porcine models (Yorkshire pigs weighing 30-40 kg), a v-ECG and conventional ECG were taken simultaneously during LVAD perfusion. Clinical experts found 104 abnormal heartbeats from the saved conventional ECG data and confirmed that the other 3159 heartbeats were normal. Almost all of the abnormal heartbeats were premature ventricular contractions (PVCs), and there was short-term tachycardia for 3 s. A personal computer was used to automatically detect abnormal heartbeats with the v-ECG according to the new method, and its results were compared with the clinicians' results. The new method found abnormal heartbeats with 90% accuracy, and less than 15% of the total PVCs were missed. Copyright © 2014 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Statin-associated muscle symptoms: impact on statin therapy-European Atherosclerosis Society Consensus Panel Statement on Assessment, Aetiology and Management.

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Stroes, Erik S; Thompson, Paul D; Corsini, Alberto; Vladutiu, Georgirene D; Raal, Frederick J; Ray, Kausik K; Roden, Michael; Stein, Evan; Tokgözoğlu, Lale; Nordestgaard, Børge G; Bruckert, Eric; De Backer, Guy; Krauss, Ronald M; Laufs, Ulrich; Santos, Raul D; Hegele, Robert A; Hovingh, G Kees; Leiter, Lawrence A; Mach, Francois; März, Winfried; Newman, Connie B; Wiklund, Olov; Jacobson, Terry A; Catapano, Alberico L; Chapman, M John; Ginsberg, Henry N

2015-05-01

Statin-associated muscle symptoms (SAMS) are one of the principal reasons for statin non-adherence and/or discontinuation, contributing to adverse cardiovascular outcomes. This European Atherosclerosis Society (EAS) Consensus Panel overviews current understanding of the pathophysiology of statin-associated myopathy, and provides guidance for diagnosis and management of SAMS. Statin-associated myopathy, with significant elevation of serum creatine kinase (CK), is a rare but serious side effect of statins, affecting 1 per 1000 to 1 per 10 000 people on standard statin doses. Statin-associated muscle symptoms cover a broader range of clinical presentations, usually with normal or minimally elevated CK levels, with a prevalence of 7-29% in registries and observational studies. Preclinical studies show that statins decrease mitochondrial function, attenuate energy production, and alter muscle protein degradation, thereby providing a potential link between statins and muscle symptoms; controlled mechanistic and genetic studies in humans are necessary to further understanding. The Panel proposes to identify SAMS by symptoms typical of statin myalgia (i.e. muscle pain or aching) and their temporal association with discontinuation and response to repetitive statin re-challenge. In people with SAMS, the Panel recommends the use of a maximally tolerated statin dose combined with non-statin lipid-lowering therapies to attain recommended low-density lipoprotein cholesterol targets. The Panel recommends a structured work-up to identify individuals with clinically relevant SAMS generally to at least three different statins, so that they can be offered therapeutic regimens to satisfactorily address their cardiovascular risk. Further research into the underlying pathophysiological mechanisms may offer future therapeutic potential. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Cardiology.

Dry eye disease: pathophysiology, classification, and diagnosis.

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Perry, Henry D

2008-04-01

Dry eye disease (DED) is a multifactorial disorder of the tear film and ocular surface that results in eye discomfort, visual disturbance, and often ocular surface damage. Although recent research has made progress in elucidating DED pathophysiology, currently there are no uniform diagnostic criteria. This article discusses the normal anatomy and physiology of the lacrimal functional unit and the tear film; the pathophysiology of DED; DED etiology, classification, and risk factors; and DED diagnosis, including symptom assessment and the roles of selected diagnostic tests.

Hsp72 preserves muscle function and slows progression of severe muscular dystrophy.

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Gehrig, Stefan M; van der Poel, Chris; Sayer, Timothy A; Schertzer, Jonathan D; Henstridge, Darren C; Church, Jarrod E; Lamon, Severine; Russell, Aaron P; Davies, Kay E; Febbraio, Mark A; Lynch, Gordon S

2012-04-04

Duchenne muscular dystrophy (DMD) is a severe and progressive muscle wasting disorder caused by mutations in the dystrophin gene that result in the absence of the membrane-stabilizing protein dystrophin. Dystrophin-deficient muscle fibres are fragile and susceptible to an influx of Ca(2+), which activates inflammatory and muscle degenerative pathways. At present there is no cure for DMD, and existing therapies are ineffective. Here we show that increasing the expression of intramuscular heat shock protein 72 (Hsp72) preserves muscle strength and ameliorates the dystrophic pathology in two mouse models of muscular dystrophy. Treatment with BGP-15 (a pharmacological inducer of Hsp72 currently in clinical trials for diabetes) improved muscle architecture, strength and contractile function in severely affected diaphragm muscles in mdx dystrophic mice. In dko mice, a phenocopy of DMD that results in severe spinal curvature (kyphosis), muscle weakness and premature death, BGP-15 decreased kyphosis, improved the dystrophic pathophysiology in limb and diaphragm muscles and extended lifespan. We found that the sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase (SERCA, the main protein responsible for the removal of intracellular Ca(2+)) is dysfunctional in severely affected muscles of mdx and dko mice, and that Hsp72 interacts with SERCA to preserve its function under conditions of stress, ultimately contributing to the decreased muscle degeneration seen with Hsp72 upregulation. Treatment with BGP-15 similarly increased SERCA activity in dystrophic skeletal muscles. Our results provide evidence that increasing the expression of Hsp72 in muscle (through the administration of BGP-15) has significant therapeutic potential for DMD and related conditions, either as a self-contained therapy or as an adjuvant with other potential treatments, including gene, cell and pharmacological therapies.

Evaluation of left ventricular function by cardiac CT

International Nuclear Information System (INIS)

Naito, Hiroaki; Kozuka, Takahiro

1982-01-01

Left ventricular function was evaluated by CT, which was compared with the data of left ventriculography for various cardiac diseases. The end diastolic volume of the left ventricle can be readily computed from CT, with a satisfactory correlation with that of left ventriculography (r = 0.95). The left ventricular ejection fraction, calculated from the areal ratio of the left ventricular lumen in end-diastolic imaging to that in end-sytolic imaging, also roughly reflects left ventricular contractile function, but shows correlation with left ventriculography by only r = 0.79. Although the cardiac output is not sensitive for functional evaluation, it can be directly calculated by means of dynamic scanning and shows a satisfactory correlation with the ear piece pigment dilution (r = 0.85). Evaluation of left ventricular function by CT shows a high precision in comparison with left ventriculography, but still lacks temporal resolving power. (Chiba, N.)

[Ventricular tachycardia in a patient with rate-responsive cardiac pacemaker].

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Himbert, C; Lascault, G; Tonet, J; Coutte, R; Busquet, P; Frank, R; Grosgogeat, Y

1992-11-01

The authors report a case of syncopal ventricular tachycardia in a patient with a respiratory-dependent rate responsive pacemaker, followed-up for valvular heart disease with severe left ventricular dysfunction and sustained atrial and ventricular arrhythmias. The introduction of low dose betablocker therapy with reinforcement of the treatment of cardiac failure controlled the ventricular arrhythmia, after suppression of the data responsive function had been shown to be ineffective. The authors discuss the role of the rate responsive function in the triggering of the ventricular tachycardias.

Hypertrophic cardiomyopathy with mid-ventricular obstruction and apical aneurysm

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N.D. Oryshchyn

2016-11-01

Full Text Available A case report of apical left ventricular aneurysm in patient with hypertrophic cardiomyopathy with mid-ventricular obstruction (diagnosis and surgical treatment is presented. We revealed apical aneurysm and mid-ventricular obstruction during echocardiography and specified anatomical characteristics of aneurysm during computer tomography. There was no evidence of obstructive coronary artery disease during coronary angiography. Taking into consideration multiple cerebral infarcts, aneurysm resection and left ventricular plastics was performed. Electronic microscopy of myocardium confirmed the diagnosis of hypertrophic cardiomyopathy.

Translating golden retriever muscular dystrophy microarray findings to novel biomarkers for cardiac/skeletal muscle function in Duchenne muscular dystrophy.

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Galindo, Cristi L; Soslow, Jonathan H; Brinkmeyer-Langford, Candice L; Gupte, Manisha; Smith, Holly M; Sengsayadeth, Seng; Sawyer, Douglas B; Benson, D Woodrow; Kornegay, Joe N; Markham, Larry W

2016-04-01

In Duchenne muscular dystrophy (DMD), abnormal cardiac function is typically preceded by a decade of skeletal muscle disease. Molecular reasons for differences in onset and progression of these muscle groups are unknown. Human biomarkers are lacking. We analyzed cardiac and skeletal muscle microarrays from normal and golden retriever muscular dystrophy (GRMD) dogs (ages 6, 12, or 47+ mo) to gain insight into muscle dysfunction and to identify putative DMD biomarkers. These biomarkers were then measured using human DMD blood samples. We identified GRMD candidate genes that might contribute to the disparity between cardiac and skeletal muscle disease, focusing on brain-derived neurotropic factor (BDNF) and osteopontin (OPN/SPP1, hereafter indicated as SPP1). BDNF was elevated in cardiac muscle of younger GRMD but was unaltered in skeletal muscle, while SPP1 was increased only in GRMD skeletal muscle. In human DMD, circulating levels of BDNF were inversely correlated with ventricular function and fibrosis, while SPP1 levels correlated with skeletal muscle function. These results highlight gene expression patterns that could account for differences in cardiac and skeletal disease in GRMD. Most notably, animal model-derived data were translated to DMD and support use of BDNF and SPP1 as biomarkers for cardiac and skeletal muscle involvement, respectively.

95th Anniversary of Pathophysiology in Croatia.

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Kovač, Zdenko

2017-12-01

University level of Pathophysiology research and teaching in Croatia had started with the third year of Medical School of Zagreb in academic year 1919./20. Ever since, despite historical changes of the main university stake holder, the state of Croatia, Department of Pathophysiology development progressed and has made visible academic achievements, with a broader effect in medical community. The first 95 years of academic tradition and major achievements are shortly described in this paper. Professor Miroslav Mikuličić envisioned Pathophysiology in close relations with Pharmacology and made the pioneering steps of establishing the "double" department at Šalata. His group was academically very pro-active, with strong international scientific participation and recruitment of professionals. The group published the first voluminous textbook of Pharmacology and Pathophysiology, in Croatian. In fifties, professor Pavao Sokolić established clinical pathophysiology within the Hospital Centre at Rebro. Out of "double" department two new departments were founded, the Pathophysiology one was completed with the clinical ward. That institutional move from Šalata hill to the Rebro hill was a necessary gigantic step and a prerequisite for the proper further development. It was in accordance with the concept of the Mikuličić's program of Pathophysiology from 1917. Pavao Sokolić has been remembered for his visions, deep insights into etiopathogenesis, ability to transfer knowledge and friendly relations to students. Sharp intellectual power, emanating charisma, academic erudition and unique clinical competencies made the legendary image of the "Teacher" - as students used to refer to him with admiration. He was second to no one when complex patient issues were to be resolved. Clinical Hospital Centre Zagreb and his Department at Rebro have become a referral point to whom to go to despair. Students recognized in their Teacher the landmark of Croatian medicine, which made a

Up-regulation of mRNA ventricular PRNP prion protein gene expression in air pollution highly exposed young urbanites: endoplasmic reticulum stress, glucose regulated protein 78, and nanosized particles.

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Villarreal-Calderon, Rodolfo; Franco-Lira, Maricela; González-Maciel, Angélica; Reynoso-Robles, Rafael; Harritt, Lou; Pérez-Guillé, Beatriz; Ferreira-Azevedo, Lara; Drecktrah, Dan; Zhu, Hongtu; Sun, Qiang; Torres-Jardón, Ricardo; Aragón-Flores, Mariana; Calderón-Garcidueñas, Ana; Diaz, Philippe; Calderón-Garcidueñas, Lilian

2013-11-28

Mexico City Metropolitan Area children and young adults exposed to high concentrations of air pollutants including fine and ultrafine particulate matter (PM) vs. clean air controls, exhibit myocardial inflammation and inflammasome activation with a differential right and left ventricular expression of key inflammatory genes and inflammasomes. We investigated the mRNA expression levels of the prion protein gene PRNP, which plays an important role in the protection against oxidative stress and metal toxicity, and the glucose regulated protein 78, a key protein in endoplasmic reticulum (ER) stress signaling, in ventricular autopsy samples from 30 children and young adults age 19.97 ± 6.8 years with a lifetime of low (n:4) vs. high (n:26) air pollution exposures. Light microscopy and transmission electron microscopy studies were carried out in human ventricles, and electron microscopy studies were also done in 5 young, highly exposed Mexico City dogs. There was significant left ventricular PRNP and bi-ventricular GRP78 mRNA up-regulation in Mexico City young urbanites vs. controls. PRNP up-regulation in the left ventricle was significantly different from the right, p < 0.0001, and there was a strong left ventricular PRNP and GRP78 correlation (p = 0.0005). Marked abnormalities in capillary endothelial cells, numerous nanosized particles in myocardial ER and in abnormal mitochondria characterized the highly exposed ventricles. Early and sustained cardiac ER stress could result in detrimental irreversible consequences in urban children, and while highly complex systems maintain myocardial homeostasis, failure to compensate for chronic myocardial inflammation, oxidative and ER stress, and particles damaging myocardial organelles may prime the development of pathophysiological cardiovascular states in young urbanites. Nanosized PM could play a key cardiac myocyte toxicity role.

Up-Regulation of mRNA Ventricular PRNP Prion Protein Gene Expression in Air Pollution Highly Exposed Young Urbanites: Endoplasmic Reticulum Stress, Glucose Regulated Protein 78, and Nanosized Particles

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Rodolfo Villarreal-Calderon

2013-11-01

Full Text Available Mexico City Metropolitan Area children and young adults exposed to high concentrations of air pollutants including fine and ultrafine particulate matter (PM vs. clean air controls, exhibit myocardial inflammation and inflammasome activation with a differential right and left ventricular expression of key inflammatory genes and inflammasomes. We investigated the mRNA expression levels of the prion protein gene PRNP, which plays an important role in the protection against oxidative stress and metal toxicity, and the glucose regulated protein 78, a key protein in endoplasmic reticulum (ER stress signaling, in ventricular autopsy samples from 30 children and young adults age 19.97 ± 6.8 years with a lifetime of low (n:4 vs. high (n:26 air pollution exposures. Light microscopy and transmission electron microscopy studies were carried out in human ventricles, and electron microscopy studies were also done in 5 young, highly exposed Mexico City dogs. There was significant left ventricular PRNP and bi-ventricular GRP78 mRNA up-regulation in Mexico City young urbanites vs. controls. PRNP up-regulation in the left ventricle was significantly different from the right, p < 0.0001, and there was a strong left ventricular PRNP and GRP78 correlation (p = 0.0005. Marked abnormalities in capillary endothelial cells, numerous nanosized particles in myocardial ER and in abnormal mitochondria characterized the highly exposed ventricles. Early and sustained cardiac ER stress could result in detrimental irreversible consequences in urban children, and while highly complex systems maintain myocardial homeostasis, failure to compensate for chronic myocardial inflammation, oxidative and ER stress, and particles damaging myocardial organelles may prime the development of pathophysiological cardiovascular states in young urbanites. Nanosized PM could play a key cardiac myocyte toxicity role.

Bidirectional ventricular tachycardia of unusual etiology

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Praloy Chakraborty

2015-11-01

Full Text Available Bidirectional ventricular tachycardia (BDVT is a rare form of ventricular arrhythmia, characterized by changing QRS axis of 180 degrees. Digitalis toxicity is considered as commonest cause of BDVT; other causes include aconite toxicity, myocarditis, myocardial infarction, metastatic cardiac tumour and cardiac channelopathies. We describe a case of BDVT in a patient with Anderson-Tawil syndrome.

Evaluation of ventricular function in patients with coronary artery disease

International Nuclear Information System (INIS)

Rocco, T.P.; Dilsizian, V.; Fischman, A.J.; Strauss, H.W.

1989-01-01

The recent expansion of interventional cardiovascular technologies has stimulated a concomitant expansion of noninvasive cardiac studies, both to assist in diagnosis and to evaluate treatment outcomes. Radionuclide ventricular function studies provide a reliable, reproducible means to quantify global left ventricular systolic performance, a critical determinant of prognosis in patients with cardiovascular disease. In addition, the ability to evaluate regional left ventricular wall motion and to assess ventricular performance during exercise have secured a fundamental role for such studies in the screening and treatment of patients with coronary artery disease. Radionuclide techniques have been extended to the evaluation of left ventricular relaxation/filling events, left ventricular systolic/diastolic function in the ambulatory setting, and with appropriate technical modifications, to the assessment of right ventricular performance at rest and with exercise. As a complement to radionuclide perfusion studies, cardiac blood-pool imaging allows for thorough noninvasive description of cardiac physiology and function in both normal subjects and in patients with a broad range of cardiovascular diseases. 122 references

Ventricular Septal Dissection Complicating Inferior Wall Myocardial Infarction

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Lindsey Kalvin

2017-01-01

Full Text Available Postmyocardial infarction ventricular septal defect is an increasingly rare mechanical complication of acute myocardial infarction. We present a case of acute myocardial infarction from right coronary artery occlusion that developed hypotension and systolic murmur 12 hours after successful percutaneous coronary intervention. Although preoperative imaging suggested a large ventricular septal defect and a pseudoaneurysm, intraoperative findings concluded a serpiginous dissection of the ventricular septum. The imaging technicalities are discussed.

Voltage-Gated Sodium Channel β1/β1B Subunits Regulate Cardiac Physiology and Pathophysiology

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Nnamdi Edokobi

2018-04-01

Full Text Available Cardiac myocyte contraction is initiated by a set of intricately orchestrated electrical impulses, collectively known as action potentials (APs. Voltage-gated sodium channels (NaVs are responsible for the upstroke and propagation of APs in excitable cells, including cardiomyocytes. NaVs consist of a single, pore-forming α subunit and two different β subunits. The β subunits are multifunctional cell adhesion molecules and channel modulators that have cell type and subcellular domain specific functional effects. Variants in SCN1B, the gene encoding the Nav-β1 and -β1B subunits, are linked to atrial and ventricular arrhythmias, e.g., Brugada syndrome, as well as to the early infantile epileptic encephalopathy Dravet syndrome, all of which put patients at risk for sudden death. Evidence over the past two decades has demonstrated that Nav-β1/β1B subunits play critical roles in cardiac myocyte physiology, in which they regulate tetrodotoxin-resistant and -sensitive sodium currents, potassium currents, and calcium handling, and that Nav-β1/β1B subunit dysfunction generates substrates for arrhythmias. This review will highlight the role of Nav-β1/β1B subunits in cardiac physiology and pathophysiology.

Effect of chronic right ventricular apical pacing on left ventricular function.

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O'Keefe, James H; Abuissa, Hussam; Jones, Philip G; Thompson, Randall C; Bateman, Timothy M; McGhie, A Iain; Ramza, Brian M; Steinhaus, David M

2005-03-15

The determinants of change in left ventricular (LV) ejection fraction (EF) over time in patients with impaired LV function at baseline have not been clearly established. Using a nuclear database to assess changes in LV function over time, we included patients with a baseline LVEF of 25% to 40% on a gated single-photon emission computed tomographic study at rest and only if second-gated photon emission computed tomography performed approximately 18 months after the initial study showed an improvement in LVEF at rest of > or =10 points or a decrease in LVEF at rest of > or =7 points. In all, 148 patients qualified for the EF increase group and 59 patients for the EF decrease group. LVEF on average increased from 33 +/- 4% to 51 +/- 8% in the EF increase group and decreased from 35 +/- 4% to 25 +/- 5% in the EF decrease group. The strongest multivariable predictor of improvement of LVEF was beta-blocker therapy (odds ratio 3.9, p = 0.002). The strongest independent predictor of LVEF decrease was the presence of a permanent right ventricular apical pacemaker (odds ratio 6.6, p = 0.002). Thus, this study identified beta-blocker therapy as the major independent predictor for improvement in LVEF of > or =10 points, whereas a permanent pacemaker (right ventricular apical pacing) was the strongest predictor of a LVEF decrease of > or =7 points.

Pathophysiology of gastroesophageal reflux disease

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Boeckxstaens, Guy E.; Rohof, Wout O.

2014-01-01

Gastroesophageal reflux disease (GERD) is one of the most common digestive diseases in the Western world, with typical symptoms, such as heartburn, regurgitation, or retrosternal pain, reported by 15% to 20% of the general population. The pathophysiology of GERD is multifactorial. Our understanding

Pathophysiological mechanisms of insulin resistance

NARCIS (Netherlands)

Brands, M.

2013-01-01

In this thesis we studied pathophysiological mechanisms of insulin resistance in different conditions in humans, i.e. in obesity, during lipid infusions, after hypercaloric feeding, and glucocorticoid treatment. We focused on 3 important hypotheses that are suggested to be implicated in the

The helical ventricular myocardial band of Torrent-Guasp.

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Kocica, Mladen J; Corno, Antonio F; Lackovic, Vesna; Kanjuh, Vladimir I

2007-01-01

We live in an era of substantial progress in understanding myocardial structure and function at genetic, molecular, and microscopic levels. Yet, ventricular myocardium has proven remarkably resistant to macroscopic analyses of functional anatomy. Pronounced and practically indefinite global and local structural anisotropy of its fibers and other ventricular wall constituents produces electrical and mechanical properties that are nonlinear, anisotropic, time varying, and spatially inhomogeneous. The helical ventricular myocardial band of Torrent-Guasp is a revolutionary new concept in understanding global, 3-dimensional, functional architecture of the ventricular myocardium. This concept defines the principal, cumulative vectors, integrating the tissue architecture (ie, form) and net forces developed (ie, function) within the ventricular mass. The primary purpose of this review is to emphasize the importance of this concept, in the light of collaborative efforts to establish an integrative approach, defining ventricular form and function by linking across multiple scales of biological organization, as explained in the ongoing Physiome project. Because one of the most important scientific missions in this century is integration of basic research with clinical medicine, we believe that this knowledge is not of merely academic importance, but is also the essential prerequisite in clinical evaluation and treatment of different heart diseases.

Clinical studies on myocardial perfusion imaging in patients with right ventricular overload

International Nuclear Information System (INIS)

Abo, Kenji; Yamagata, Takashi; Nakajima, Masao; Fujita, Kimiaki; Morita, Nobuo

1979-01-01

Patients with heart disease which had been clinically diagnosed underwent 201 Tl myocardial perfusion imaging. The thickness of right ventricular wall measured from original images was directly proportional to systolic pressure of the right ventricle measured by cardiac catheterization, and 201 Tl activity in the right ventricle was more directly proportional to systolic pressure of the right ventricle. Imaging patterns of various diseases were also described. Images of patients with hypertrophic cardiomyopathy revealed that right ventricular wall was thin and right ventricular cavity was small, but the thickness of septal wall and left ventricular wall were maximal. Images of patients with mitral insufficiency revealed that the thickness of right ventricular wall, septal wall, and left ventricular wall was medium, and the right ventricular cavity was smaller than the left ventricular cavity. Images of patients with congestive cardiomyopathy and congestive cardiac failure showed that enlargement of both ventricular cavities was disproportionate to the thickness of each wall. Images of patients with arterial septal defect revealed that the thickness of each wall was comparatively normal, the right ventricular cavity was maximal, and the left ventricular cavity was minimal. Images of patients with primary pulmonary hypertention, pulmonary stenosis and tetralogy of Fallot in whom pressure overload was recognized revealed severe thickenings of right ventricular wall, moderate enlargement of the right ventricle, small left ventricle, and thin left ventricular wall. (Tsunoda, M.)

Assessing pathophysiology of cancer anorexia.

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Laviano, Alessandro; Koverech, Angela; Seelaender, Marilia

2017-09-01

Cancer anorexia is a negative prognostic factor and is broadly defined as the loss of the interest in food. However, multiple clinical domains contribute to the phenotype of cancer anorexia. The characterization of the clinical and molecular pathophysiology of cancer anorexia may enhance the efficacy of preventive and therapeutic strategies. Clinical trials showed that cancer anorexia should be considered as an umbrella encompassing different signs and symptoms contributing to appetite disruption in cancer patients. Loss of appetite, early satiety, changes in taste and smell are determinants of cancer anorexia, whose presence should be assessed in cancer patients. Interestingly, neuronal correlates of cancer anorexia-related symptoms have been revealed by brain imaging techniques. The pathophysiology of cancer anorexia is complex and involves different domains influencing eating behavior. Limiting the assessment of cancer anorexia to questions investigating changes in appetite may impede correct identification of the targets to address.

Procollagen type III amino terminal peptide and myocardial fibrosis: A study in hypertensive patients with and without left ventricular hypertrophy.

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dos Santos Moreira, Carlos; Serejo, Fátima; Alcântara, Paula; Ramalhinho, Vítor; Braz Nogueira, J

2015-05-01

An exaggerated accumulation of type I and type III fibrillar collagens occurs throughout the free wall and interventricular septum of patients with primary hypertension and left ventricular hypertrophy (LVH). In the present study the serum concentration of procollagen type III amino terminal peptide (PIIIP) was measured to determine the value of this peptide as a potential marker of ventricular fibrosis in hypertensive patients, particularly those with LVH. The study population consisted of patients with never-treated mild to moderate essential hypertension and 30 normotensive control subjects. Clinical, echocardiographic, electrocardiographic and biochemical parameters were assessed in all patients. Heart rate, body mass index and levels of blood pressure were increased in hypertensives, particularly those with LVH, compared to normotensive controls. Posterior wall thickness, left ventricular (LV) mass and LV mass index, and serum PIIIP concentration were also increased in hypertensives, with significant differences between the two hypertensive groups. The ratio between maximal early and late transmitral flow velocity measured during diastole was lower in hypertensives, particularly those with LVH, than in normotensive controls. The increase in PIIIP indicates that type III collagen synthesis increases in hypertensives, particularly those with LVH, implying that alterations in the heart in hypertension are the result not solely of hypertrophied LV muscle, but also of increased collagen deposition within the ventricular wall and around the coronary vessels. Thus, measurement of serum PIIIP could be a practical and useful tool in the non-invasive assessment of myocardial remodeling in hypertension. Copyright © 2014 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Bundle of measures for external cerebral ventricular drainage-associated ventriculitis.

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Chatzi, Maria; Karvouniaris, Marios; Makris, Demosthenes; Tsimitrea, Eleni; Gatos, Charalampos; Tasiou, Anastasia; Mantzarlis, Kostas; Fountas, Kostas N; Zakynthinos, Epaminondas

2014-01-01

To assess the prevalence and outcome of external cerebral ventricular drainage-associated ventriculitis in neurocritical patients before and after the implementation of a bundle of external cerebral ventricular drainage-associated ventriculitis control measures. Clinical prospective case series. University Hospital of Larissa, Greece. Consecutive patients were recruited from the ICU of the hospital. Patient inclusion criteria included presence of external ventricular drainage and ICU stay more than 48 hours. The bundle of external cerebral ventricular drainage-associated ventriculitis control measures included 1) reeducation of ICU personnel on issues of infection control related to external cerebral ventricular drainage, 2) meticulous intraventricular catheter handling, 3) cerebrospinal fluid sampling only when clinically necessary, and 4) routine replacement of the drainage catheter on the seventh drainage day if the catheter was still necessary. The bundle was applied after an initial period (preintervention) where standard policy for external cerebral ventricular drainage-associated ventriculitis was established. External cerebral ventricular drainage-associated ventriculitis prevalence, external cerebral ventricular drainage-associated ventriculitis events per 1,000 drainage days (drain-associated infection rate), length of ICU stay, Glasgow Outcome Scale at 6 months, and risk factors for external cerebral ventricular drainage-associated ventriculitis. Eighty-two patients entered the study in the preintervention period and 57 patients during the intervention period. During the preintervention and intervention period, external cerebral ventricular drainage-associated ventriculitis prevalence was 28% and 10.5% (p = 0.02) and drain-associated infection rate was 18 and 7.1, respectively (p = 0.0001); mean (95% CI) length of ICU stay in patients who presented external cerebral ventricular drainage-associated ventriculitis was 44.4 days (36.4-52.4 d), whereas mean

SERUM IGF-I AND HORMONAL RESPONSES TO INCREMENTAL EXERCISE IN ATHLETES WITH AND WITHOUT LEFT VENTRICULAR HYPERTROPHY

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Aleksandra Zebrowska

2009-03-01

Full Text Available We investigated the response of insulin-like growth factor (IGF- I, insulin-like growth factor binding protein-3 (IGFBP-3 and some hormones, i.e., testosterone (T, growth hormone (GH, cortisol (C, and insulin (I, to maximal exercise in road cyclists with and without diagnosed left ventricular hypertrophy. M-mode and two-dimensional Doppler echocardiography was performed in 30 professional male endurance athletes and a group of 14 healthy untrained subjects using a Hewlett-Packard Image Point HX ultrasound system with standard imaging transducers. Echocardiography and an incremental physical exercise test were performed during the competitive season. Venous blood samples were drawn before and immediately after the maximal cycling exercise test for determination of somatomedin and hormonal concentrations. The basal concentration of IGF-I was statistically higher (p < 0.05 in athletes with left ventricular muscle hypertrophy (LVH when compared to athletes with a normal upper limit of the left ventricular wall (LVN (p < 0.05 and to the control group (CG (p < 0.01. The IGF-I level increased significantly at maximal intensity of incremental exercise in CG (p < 0.01, LVN (p < 0.05 and LVH (p < 0.05 compared to respective values at rest. Long-term endurance training induced an increase in resting (p < 0.01 and post-exercise (p < 0.05 IGF-I/IGFBP-3 ratio in athletes with LVH compared to LVN. The testosterone (T level was lower in LVH at rest compared to LVN and CG groups (p < 0.05. These results indicate that resting serum IGF-I concentration were higher in trained subjects with LVH compared to athletes without LVH. Serum IGF- I/IGFBP-3 elevation at rest and after exercise might suggest that IGF-I act as a potent stimulant of left ventricular hypertrophy in chronically trained endurance athletes

Skeletal muscle beta-receptors and isoproterenol-stimulated vasodilation in canine heart failure

International Nuclear Information System (INIS)

Frey, M.J.; Lanoce, V.; Molinoff, P.B.; Wilson, J.R.

1989-01-01

To investigate whether heart failure alters beta-adrenergic receptors on skeletal muscle and its associated vasculature, the density of beta-adrenergic receptors, isoproterenol-stimulated adenylate cyclase activity, and coupling of the guanine nucleotide-binding regulatory protein were compared in 18 control dogs and 16 dogs with heart failure induced by 5-8 wk of ventricular pacing at 260 beats/min. Hindlimb vascular responses to isoproterenol were compared in eight controls and eight of the dogs with heart failure. In dogs with heart failure, the density of beta-receptors on skeletal muscle was reduced in both gastrocnemius (control: 50 +/- 5; heart failure: 33 +/- 8 fmol/mg of protein) and semitendinosus muscle (control: 43 +/- 9; heart failure: 27 +/- 9 fmol/mg of protein, both P less than 0.05). Receptor coupling to the ternary complex, as determined by isoproterenol competition curves with and without guanosine 5'-triphosphate (GTP), was unchanged. Isoproterenol-stimulated adenylate cyclase activity was significantly decreased in semitendinosus muscle (control: 52.4 +/- 4.6; heart failure: 36.5 +/- 9.5 pmol.mg-1.min-1; P less than 0.05) and tended to be decreased in gastrocnemius muscle (control: 40.1 +/- 8.5; heart failure: 33.5 +/- 4.5 pmol.mg-1.min-1; P = NS). Isoproterenol-induced hindlimb vasodilation was not significantly different in controls and in dogs with heart failure. These findings suggest that heart failure causes downregulation of skeletal muscle beta-adrenergic receptors, probably due to receptor exposure to elevated catecholamine levels, but does not reduce beta-receptor-mediated vasodilation in muscle

Does in-hospital ventricular fibrillation affect prognosis after myocardial infarction?

DEFF Research Database (Denmark)

Jensen, G V; Torp-Pedersen, C; Hildebrandt, P

1997-01-01

with ventricular fibrillation in time intervals, indicated that the importance of ventricular fibrillation for risk of death was exhausted during the initial 60 days after infarction. CONCLUSION: Ventricular fibrillation is associated with an independent increased risk of death within 0-60 days after infarction......AIM: The aim of this study was to estimate the prognostic information to be gained from ventricular fibrillation in patients with myocardial infarction. METHODS AND RESULTS: We studied 4259 consecutive patients with myocardial infarction admitted to one centre in 1977-1988. Five hundred and twenty......-eight (12.4%) of the patients had ventricular fibrillation in hospital. The following risk factors were included in multivariate models to estimate their importance for 30-day and long-term (median 7 year) prognosis: age, gender, ventricular fibrillation, congestive heart failure, pulmonary oedema...

Evaluation of left ventricular function using digital subtraction ventriculography

International Nuclear Information System (INIS)

Yiannikas, J.; Detrano, R.

1986-01-01

Digital subtraction ventriculography following injections of contrast via peripheral veins provides excellent images to assess left ventricular function. The images are essentially identical to those following DCV, but allow more uniform mixing of contrast in the left ventricular chamber. Furthermore, few, if any, cardiac arrhythmias occur, hence obviating difficulties that arise from DCV. The spatial resolution of the method is such that regional wall motion assessment of ventricular function is more accurate than that of other noninvasive imaging methods. The use of video-densitometry allows accurate assessment of left ventricular function even when the left ventricular cavity is nonsymmetrically deformed and aneurysmal. In the setting of the cardiac catheterization laboratory, digital ventriculography may provide a safer means of assessing left ventricular function when critical coronary or myocardial disease is present and allows multiple assessments of ventricular function during the same study. Although excellent correlations with standard ventriculography have been noted by all workers, significant discrepancies still exist in individual patients, particularly in the calculations of end diastolic volumes. In the authors experience and in those of most workers, the largest discrepancies existed in patients in whom suboptimal studies are included for analysis. The most frequent reason for the occasional suboptimal study as with all digital subtraction work is the misregistration that results from motion

Arrhythmogenic right ventricular cardiomyopathy: contribution of different electrocardiographic techniques.

Science.gov (United States)

Moreira, Davide; Delgado, Anne; Marmelo, Bruno; Correia, Emanuel; Gama, Pedro; Pipa, João; Nunes, Luís; Santos, Oliveira

2014-04-01

Arrhythmogenic right ventricular cardiomyopathy, also known as arrhythmogenic right ventricular dysplasia, is a condition in which myocardium is replaced by fibrous or fibrofatty tissue, predominantly in the right ventricle. It is clinically characterized by potentially lethal ventricular arrhythmias, and is a leading cause of sudden cardiac death. Its prevalence is not known exactly but is estimated at approximately 1:5000 in the adult population. Diagnosis can be on the basis of structural and functional alterations of the right ventricle, electrocardiographic abnormalities (including depolarization and repolarization alterations and ventricular arrhythmias) and family history. Diagnostic criteria facilitate the recognition and interpretation of non-specific clinical features of this disease. The authors present a case in which the diagnosis of arrhythmogenic right ventricular cardiomyopathy was prompted by the suspicion of right ventricular disease on transthoracic echocardiography. This was confirmed by detection of epsilon waves on analysis of the ECG, which generally go unnoticed but in this case were the key to the diagnosis. Their presence was also shown by non-conventional ECG techniques such as modified Fontaine ECG. The course of the disease culminated in the occurrence of ventricular tachycardia, which prompted placement of an implantable cardioverter-defibrillator. Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

The effects of denervation, reinnervation, and muscle imbalance on functional muscle length and elbow flexion contracture following neonatal brachial plexus injury.

Science.gov (United States)

Weekley, Holly; Nikolaou, Sia; Hu, Liangjun; Eismann, Emily; Wylie, Christopher; Cornwall, Roger

2012-08-01

The pathophysiology of paradoxical elbow flexion contractures following neonatal brachial plexus injury (NBPI) is incompletely understood. The current study tests the hypothesis that this contracture occurs by denervation-induced impairment of elbow flexor muscle growth. Unilateral forelimb paralysis was created in mice in four neonatal (5-day-old) BPI groups (C5-6 excision, C5-6 neurotomy, C5-6 neurotomy/repair, and C5-T1 global excision), one non-neonatal BPI group (28-day-old C5-6 excision), and two neonatal muscle imbalance groups (triceps tenotomy ± C5-6 excision). Four weeks post-operatively, motor function, elbow range of motion, and biceps/brachialis functional lengths were assessed. Musculocutaneous nerve (MCN) denervation and reinnervation were assessed immunohistochemically. Elbow flexion motor recovery and elbow flexion contractures varied inversely among the neonatal BPI groups. Contracture severity correlated with biceps/brachialis shortening and MCN denervation (relative axon loss), with no contractures occurring in mice with MCN reinnervation (presence of growth cones). No contractures or biceps/brachialis shortening occurred following non-neonatal BPI, regardless of denervation or reinnervation. Neonatal triceps tenotomy did not cause contractures or biceps/brachialis shortening, nor did it worsen those following neonatal C5-6 excision. Denervation-induced functional shortening of elbow flexor muscles leads to variable elbow flexion contractures depending on the degree, permanence, and timing of denervation, independent of muscle imbalance. Copyright © 2012 Orthopaedic Research Society.

Epigenetic regulation of vascular smooth muscle cell function in atherosclerosis.

Science.gov (United States)

Findeisen, Hannes M; Kahles, Florian K; Bruemmer, Dennis

2013-04-01

Epigenetics involve heritable and acquired changes in gene transcription that occur independently of the DNA sequence. Epigenetic mechanisms constitute a hierarchic upper-level of transcriptional control through complex modifications of chromosomal components and nuclear structures. These modifications include, for example, DNA methylation or post-translational modifications of core histones; they are mediated by various chromatin-modifying enzymes; and ultimately they define the accessibility of a transcriptional complex to its target DNA. Integrating epigenetic mechanisms into the pathophysiologic concept of complex and multifactorial diseases such as atherosclerosis may significantly enhance our understanding of related mechanisms and provide promising therapeutic approaches. Although still in its infancy, intriguing scientific progress has begun to elucidate the role of epigenetic mechanisms in vascular biology, particularly in the control of smooth muscle cell phenotypes. In this review, we will summarize epigenetic pathways in smooth muscle cells, focusing on mechanisms involved in the regulation of vascular remodeling.

Co-contraction behaviour of masticatory and neck muscles during tooth grinding.

Science.gov (United States)

Giannakopoulos, N N; Schindler, H J; Hellmann, D

2018-07-01

The objective of this study was to analyse the co-contraction behaviour of jaw and neck muscles during force-controlled experimental grinding in the supine position. Twelve symptom-free subjects were enrolled in the experimental study. Electromyographic (EMG) activity of semispinalis capitis, splenius capitis and levator scapulae muscles was recorded bilaterally with intramuscular fine-wire electrodes, whereas that of sternocleidomastoideus, infrahyoidal, suprahyoidal, masseter and anterior temporalis muscles were registered with surface electrodes. EMG and force measurements were performed during tasks simulating tooth grinding on custom-made intraoral metal splints. The mean EMG activity normalised by maximum voluntary contraction (% MVC) of each of the neck muscles studied during grinding was analysed and compared with previous data from jaw clenching at identical force (100 N) and (supine) position. The occurrence of low-level, long-lasting tonic activation (LLTA) of motor units was also documented. The mean three-dimensional force vector of the grinding forces was 106 ± 74 N. In the frontal plane, the incline to the midsagittal plane ranged between 10° and 15°. In the midsagittal plane, the incline to the frontal plane was negligibly small. Posterior neck muscle activity during grinding ranged between 4.5% and 12% MVC and during clenching with 100 N between 1.8% and 9.9% MVC. Masticatory muscle activity during grinding ranged between 17% and 21% MVC for contralateral masseter and ipsilateral temporalis and between 4% and 6.5% for ipsilateral masseter and contralateral temporalis. LLTA had an average duration of 195 ± 10 seconds. The findings from this study do not support pathophysiological muscle chain theories postulating simple biomechanical coupling of neck and jaw muscles. Co-contractions of neck and masticatory muscles may instead occur as a result of complex neurophysiological interactions. © 2018 John Wiley & Sons Ltd.

A case of short-coupled premature ventricular beat-induced ventricular fibrillation with early repolarization in the inferolateral leads

Directory of Open Access Journals (Sweden)

Hidekazu Kondo, MD

2015-02-01

Full Text Available This case report describes a 19-year-old man with early repolarization (ER in the inferolateral leads and a normal QT interval who survived a cardiac arrest that was likely related to polymorphic ventricular tachycardia (VT. Electrocardiograms (ECGs also showed unifocal premature ventricular beats (PVBs with a relatively narrow QRS duration. A Holter ECG documented occasional short-coupled PVBs following non-sustained VTs. Pharmacological stress testing was also performed to assess the effects of anti-arrhythmic drugs on ER (the J wave and PVBs. We performed successful radiofrequency catheter ablation to prevent the recurrence of ventricular fibrillation after cardioverter-defibrillator implantation.

The management of ventricular dysrhythmia in aconite poisoning.

Science.gov (United States)

Coulson, James M; Caparrotta, Thomas M; Thompson, John P

2017-06-01

Aconite poisoning is relatively rare but is frequently complicated by ventricular dysrhythmias, which may be fatal. Molecular basis of aconite alkaloid ventricular arrhythmogenicity: Aconite exerts its toxic effects due to the presence of an admixture of alkaloids present in all parts of the plant. The major target of these aconite alkaloids is the fast voltage-gates sodium channel, where they cause persistent activation. This blockade of the channel in the activated state promotes automaticity within the ventricular myocardium and the generation of ventricular arrhythmias. Aconitine-induced arrhythmias: Aconite alkaloids are known to cause many different types of disturbance of heart rhythm. However, this focused review specifically looks at ventricular rhythm disturbances, namely ventricular ectopy, ventricular tachycardia, torsades des pointes and ventricular fibrillation. The objective of this review was to identify the outcome of anti-dysrhythmic strategies from animal studies and case reports in humans in order to guide the management of ventricular dysrhythmias in aconite poisoning in humans. A review of the literature in English was conducted in PubMed and Google Scholar from 1966 to July 2016 using the search terms "aconite/aconitine"; "aconite/aconitine + poisoning" and "aconite/aconitine + dysrhythmia". 168 human case-reports and case-series were identified by these searches, of which 103 were rejected if exposure to aconite did not result in ventricular dysrhythmias, if it was uncertain as to whether aconite had been ingested, if other agents were co-ingested, if there was insufficient information to determine the type of treatments administered or if there was insufficient information to determine outcome. Thus, 65 case reports of probable aconite poisoning that resulted in ventricular dysrhythmias were identified. Toxicokinetic data in aconite poisoning: Data were only available in three papers; the presence of ventricular rhythm disturbances

Effect of fluid loading on left ventricular volume and stroke volume variability in patients with end-stage renal disease: a pilot study

Science.gov (United States)

Kanda, Hirotsugu; Hirasaki, Yuji; Iida, Takafumi; Kanao-Kanda, Megumi; Toyama, Yuki; Kunisawa, Takayuki; Iwasaki, Hiroshi

2015-01-01

Purpose The aim of this study was to investigate fluid loading-induced changes in left ventricular end-diastolic volume (LVEDV) and stroke volume variability (SVV) in patients with end-stage renal disease (ESRD) using real-time three-dimensional transesophageal echocardiography and the Vigileo-FloTrac system. Patients and methods After obtaining ethics committee approval and informed consent, 28 patients undergoing peripheral vascular procedures were studied. Fourteen patients with ESRD on hemodialysis (HD) were assigned to the HD group and 14 patients without ESRD were assigned to the control group. Institutional standardized general anesthesia was provided in both groups. SVV was measured using the Vigileo-FloTrac system. Simultaneously, a full-volume three-dimensional transesophageal echocardiography dataset was acquired to measure LVEDV, left ventricular end-systolic volume, and left ventricular ejection fraction. Measurements were obtained before and after loading 500 mL hydroxyethyl starch over 30 minutes in both groups. Results In the control group, intravenous colloid infusion was associated with a significant decrease in SVV (13.8%±2.6% to 6.5%±2.6%, P<0.001) and a significant increase in LVEDV (83.6±23.4 mL to 96.1±28.8 mL, P<0.001). While SVV significantly decreased after infusion in the HD group (16.2%±6.0% to 6.2%±2.8%, P<0.001), there was no significant change in LVEDV. Conclusion Our preliminary data suggest that fluid responsiveness can be assessed not by LVEDV but also by SVV due to underlying cardiovascular pathophysiology in patients with ESRD. PMID:26527879

Efecto de la localización del electrodo ventricular derecho (tracto de salida vs. ápex sobre la sincronía ventricular mecánica, en pacientes sometidos a terapia de implante de marcapaso cardiaco Effect of right ventricular electrode location (outflow tract vs. apex on mechanical ventricular synchrony in patients that underwent pacemaker implant therapy

Directory of Open Access Journals (Sweden)

Oscar S Rincón

2008-12-01

Full Text Available Objetivo: evaluar a profundidad el efecto de la estimulación ventricular desde el tracto de salida del ventrículo derecho y el ápex, sobre la sincronía ventricular mecánica. Materiales y métodos: estudio analítico de cohorte, en el que se realizó ecocardiograma transtorácico pre y post implante de marcapaso a 20 pacientes (diez por cada grupo con indicación de marcapaso definitivo, con implante del electrodo en el tracto de salida del ventrículo derecho y el ápex, sin cardiopatía estructural, fracción de eyección > 50%; QRS y conducción aurículo-ventricular normal, con el fin de evaluar la asincronía ventricular mecánica (modo M y Doppler tisular y los parámetros de implante y programación del dispositivo. Análisis estadístico: los resultados se presentan como promedios, desviación estándar o porcentajes. Las variables continuas se compararon utilizando prueba Chi cuadrado y ANOVA. Se consideró como estadísticamente significativa una p Objective: to assess in depth the effect of ventricular stimulation from the right ventricular outflow tract and the apex on mechanical ventricular synchrony. Materials and Methods: cohort analytical study. 20 patients with indication of definitive pacemaker indication underwent transthoracic echocardiogram before and after pacemaker implant with electrode implantation in the right ventricular outflow tract and in the apex (10 patients in each group. There was no structural cardiopathy, ejection fraction was > 50%, QRS and AV conduction were normal. Mechanical ventricular asynchrony (M mode and tissue doppler and implant and device parameters were evaluated. Statistical Analysis: results are given as mean values, standard deviation or percentages. Continuous variables were compared using Chi-square test and ANOVA. A p <0.05 value was considered statistically significant. Results: in five patients (25% a pre-implant ventricular asynchrony was found; in seven (70% ventricular asynchrony

Pathophysiology and Biomarkers in Acute Ischemic Stroke – A Review

African Journals Online (AJOL)

The pathophysiology of ischemic stroke is complex, and majorly involves excitotoxicity, oxidative stress, inflammation, blood-brain barrier dysfunction, apoptosis, etc. Several of the biomarkers are related to these pathophysiologic mechanisms and they may have applications in stroke prediction, diagnosis, assessment, ...

Automatic segmentation of 4D cardiac MR images for extraction of ventricular chambers using a spatio-temporal approach

Science.gov (United States)

Atehortúa, Angélica; Zuluaga, Maria A.; Ourselin, Sébastien; Giraldo, Diana; Romero, Eduardo

2016-03-01

An accurate ventricular function quantification is important to support evaluation, diagnosis and prognosis of several cardiac pathologies. However, expert heart delineation, specifically for the right ventricle, is a time consuming task with high inter-and-intra observer variability. A fully automatic 3D+time heart segmentation framework is herein proposed for short-axis-cardiac MRI sequences. This approach estimates the heart using exclusively information from the sequence itself without tuning any parameters. The proposed framework uses a coarse-to-fine approach, which starts by localizing the heart via spatio-temporal analysis, followed by a segmentation of the basal heart that is then propagated to the apex by using a non-rigid-registration strategy. The obtained volume is then refined by estimating the ventricular muscle by locally searching a prior endocardium- pericardium intensity pattern. The proposed framework was applied to 48 patients datasets supplied by the organizers of the MICCAI 2012 Right Ventricle segmentation challenge. Results show the robustness, efficiency and competitiveness of the proposed method both in terms of accuracy and computational load.

Haemodynamic effects of dual-chamber pacing versus ventricular pacing during a walk test in patients with depressed or normal left ventricular function

Energy Technology Data Exchange (ETDEWEB)

Ferro, Adele; Salvatore, Marco; Cuocolo, Alberto [University Federico II, Department of Biomorphological and Functional Sciences, Institute of Biostructure and Bioimages of the National Council of Research, Naples (Italy); Duilio, Carlo; Santomauro, Maurizio [University Federico II, Department of Clinical Medicine, Cardiovascular and Immunological Sciences, Naples (Italy)

2005-09-01

Dual-chamber rate-modulated pacing provides haemodynamic benefits compared with ventricular pacing at rest, but it is unclear whether this also holds true during physical exercise in patients with heart failure. This study assessed the haemodynamic response to a walk test during dual-chamber pacing and ventricular pacing in patients with depressed or normal left ventricular (LV) function. Twelve patients with an LV ejection fraction <50% and 11 patients with an LV ejection fraction {>=}50% underwent two randomised 6-min walk tests under dual-chamber rate-modulated pacing and ventricular pacing at a fixed rate of 70 beats/min. All patients had a dual-chamber pacemaker implanted for complete heart block. LV function was monitored by a radionuclide ambulatory system. In patients with depressed LV function, the change from dual-chamber pacing to ventricular pacing induced a decrease in end-systolic volume at the peak of the walk test (P<0.05), with no difference in end-diastolic volume. As a consequence, higher increases in LV ejection fraction (P<0.0001) and stroke volume (P<0.01) were observed during ventricular pacing. No difference in cardiac output was found between the two pacing modes. In patients with normal LV function, the change from dual-chamber pacing to ventricular pacing induced a significant decrease in cardiac output (P<0.005 at rest and P<0.05 at the peak of the walk test). Compared with dual-chamber rate-modulated pacing, ventricular pacing improves cardiac function and does not affect cardiac output during physical activity in patients with depressed LV function, whereas it impairs cardiac output in those with normal function. (orig.)

Haemodynamic effects of dual-chamber pacing versus ventricular pacing during a walk test in patients with depressed or normal left ventricular function

International Nuclear Information System (INIS)

Ferro, Adele; Salvatore, Marco; Cuocolo, Alberto; Duilio, Carlo; Santomauro, Maurizio

2005-01-01

Dual-chamber rate-modulated pacing provides haemodynamic benefits compared with ventricular pacing at rest, but it is unclear whether this also holds true during physical exercise in patients with heart failure. This study assessed the haemodynamic response to a walk test during dual-chamber pacing and ventricular pacing in patients with depressed or normal left ventricular (LV) function. Twelve patients with an LV ejection fraction <50% and 11 patients with an LV ejection fraction ≥50% underwent two randomised 6-min walk tests under dual-chamber rate-modulated pacing and ventricular pacing at a fixed rate of 70 beats/min. All patients had a dual-chamber pacemaker implanted for complete heart block. LV function was monitored by a radionuclide ambulatory system. In patients with depressed LV function, the change from dual-chamber pacing to ventricular pacing induced a decrease in end-systolic volume at the peak of the walk test (P<0.05), with no difference in end-diastolic volume. As a consequence, higher increases in LV ejection fraction (P<0.0001) and stroke volume (P<0.01) were observed during ventricular pacing. No difference in cardiac output was found between the two pacing modes. In patients with normal LV function, the change from dual-chamber pacing to ventricular pacing induced a significant decrease in cardiac output (P<0.005 at rest and P<0.05 at the peak of the walk test). Compared with dual-chamber rate-modulated pacing, ventricular pacing improves cardiac function and does not affect cardiac output during physical activity in patients with depressed LV function, whereas it impairs cardiac output in those with normal function. (orig.)

Left ventricular mass in borderline hypertension assessed by echo cardiography

International Nuclear Information System (INIS)

Mezzasalma, L.; Ghione, S.; Palonebo, C.

1989-01-01

The relationship between clinical measurement of blood pressure (BP) and left ventricular hypertrophy in arterial hypertension appears to be weak in most studies. On the contrary, stronger correlations with target organ damage in general, and left ventricular hypertrophy in particular, have been reported for blood pressure measurements obtained by ambulatory monitoring; this finding may indicate a possible role for blood pressure response to naturally occurring stresses in determining left ventricular hypertrophy. Aim of this study was to investigate, in 18 patients with borderline arterial hypertension, the relationships between echocardiographically assessed left ventricular mass and, respectively, casual BP and BP responses to some standardized stress tests. Only three patients had a diastolic wall thickness of the interventricular septum and of the posterior wall ≥1.2 cm and none had a pathologically increased left ventricular mass index. The following statistically significant correlations were found: casual diastolic BP vs. left ventricular mass index (r=0.53, p<0.02), systolic BP response to bicycle exercise test vs. left ventricular mass index (r=0.55, p<0.05). Multiple regression analysis showed that almost fifty percent of the variability of left ventricular mass index could be predicted by these two BP measurements. These findings suggest that besides the chronically increased afterload, also the transient hypertensive responses to naturally occuring physical stresses may have a role in determining the extent of cardiac structural changes in borderline hypertensive patients. In addition, they indicate a direct relation between left ventricular mass and blood pressure levels also in borderline hypertension, as previously shown for established hypertension, despite the fact that left ventricular hypertrophy represents only an occasional finding in early stages of hypertension

[Dysphagia in Parkinson's Disease: Pathophysiology, Diagnosis and Therapy].

Science.gov (United States)

Suttrup, I; Warnecke, T

2016-07-01

Oropharyngeal and esophageal dysphagia are a frequent, but seldom diagnosed symptom of Parkinson's disease (PD). More than 80 % of patients with PD develop dysphagia during the course of their disease leading to a reduced quality of life, complicated medication intake, malnutrition and aspiration pneumonia, which is a major cause of death in PD. The underlying pathophysiology is poorly understood. Impaired dopaminergic and non-dopaminergic mechanisms of the cortical swallowing network as well as peripheral neuromuscular involvement have been suggested to contribute to its multifactorial genesis. Diagnostic screening methods include PD-specific questionnaires and a modified water test. Fiber optic endoscopic evaluation of swallowing (FEES) and videofluoroscopic swallowing study (VFSS), which complement each other, are the gold standard for evaluation of PD-related dysphagia. For evaluation of esophageal dysphagia, the high-resolution manometry (HRM) may be a helpful tool. In addition to dysphagia-specific treatment by speech and language therapists (SLTs), optimized dopaminergic medication is a meaningful therapeutic option. A promising novel method is intensive training of expiratory muscle strength (EMST). Deep brain stimulation does not seem to have a clinically relevant effect on swallowing function in PD. © Georg Thieme Verlag KG Stuttgart · New York.

Risk factors and predictors of Torsade de pointes ventricular tachycardia in patients with left ventricular systolic dysfunction receiving Dofetilide

DEFF Research Database (Denmark)

Pedersen, Henriette Sloth; Elming, Hanne; Seibaek, Marie

2007-01-01

The purpose of this study was to identify risk factors of Torsade de pointes (TdP) ventricular tachycardia in patients medicated with a class III antiarrhythmic drug (dofetilide) and left ventricular systolic dysfunction with heart failure (HF) or recent myocardial infarction (MI). The 2 Danish...

Administration of soluble activin receptor 2B increases bone and muscle mass in a mouse model of osteogenesis imperfecta

Science.gov (United States)

DiGirolamo, Douglas J.; Singhal, Vandana; Chang, Xiaoli; Lee, Se-Jin; Germain-Lee, Emily L.

2015-01-01

Osteogenesis imperfecta (OI) comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications of OI, many patients also report intolerance to physical activity, fatigue and muscle weakness. Indeed, recent studies have demonstrated that skeletal muscle is also negatively affected by OI, both directly and indirectly. Given the well-established interdependence of bone and skeletal muscle in both physiology and pathophysiology and the observations of skeletal muscle pathology in patients with OI, we investigated the therapeutic potential of simultaneous anabolic targeting of both bone and skeletal muscle using a soluble activin receptor 2B (ACVR2B) in a mouse model of type III OI (oim). Treatment of 12-week-old oim mice with ACVR2B for 4 weeks resulted in significant increases in both bone and muscle that were similar to those observed in healthy, wild-type littermates. This proof of concept study provides encouraging evidence for a holistic approach to treating the deleterious consequences of OI in the musculoskeletal system. PMID:26161291

Left ventricular systolic and diastolic function in hyperthyroidism

International Nuclear Information System (INIS)

Friedman, M.J.; Okada, R.D.; Ewy, G.A.; Hellman, D.J.

1982-01-01

In order to assess the effect of hyperthyroidism on systolic and diastolic function of the left ventricle, M-mode echocardiograms and systolic time intervals were obtained in 13 patients while they were clinically hyperthyroid and again when they were euthyroid following radioactive iodine therapy. Echocardiographic tracings of the septum and left ventricular posterior wall were digitized and analyzed to provide the maximum velocity of shortening and maximum velocity of lengthening. These velocities were normalized for left ventricular diastolic dimension. The left ventricular minor axis fractional shortening and the normalized maximum velocity of shortening were both increased during the hyperthyroid state. The normalized maximum velocity of lengthening, a measure of diastolic left ventricular function, was also increased during the hyperthyroid state when compared to the euthyroid state. The preejection period index and the preejection period/left ventricular ejection time ratio were lower when the patients were hyperthyroid than when they were euthyroid. These data confirm the increased inotropic state and demonstrated increased diastolic relaxation velocities of the hyperthyroid left ventricle

Gas embolism: pathophysiology and treatment

NARCIS (Netherlands)

van Hulst, Robert A.; Klein, Jan; Lachmann, Burkhard

2003-01-01

Based on a literature search, an overview is presented of the pathophysiology of venous and arterial gas embolism in the experimental and clinical environment, as well as the relevance and aims of diagnostics and treatment of gas embolism. The review starts with a few historical observations and

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

International Nuclear Information System (INIS)

Mishiro, Yuichiro; Oki, Takashi; Iuchi, Arata

1999-01-01

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

Cervico-mandibular muscle activity in females with chronic cervical pain

Directory of Open Access Journals (Sweden)

T. Lang

2013-12-01

Full Text Available Pathophysiological mechanisms behind pain in chroniccervical musculoskeletal conditions (MSC in office workers remainunclear. Chronic cervical pain has established links with temporomandibular(TM disorders. Yet there is no current published evidence to reportwhether individuals with cervical dysfunction exhibit altered masseterand cervical extensor (CE muscle activity. Objective: To explore CE andmasseter surface electromyographic (sEMG activity and teeth clenchinghabits in females with chronic cervical dysfunction and no TM disorder.Design: Descriptive cross-sectional correlational study with singleblinding.Participants: University students and staff with or without chroniccervical pain and no TM involvement. Methods: Descriptive and paindata captured from Research Diagnostic Criteria for TM disorders, NeckDisability Index, Computer Usage, Brief Pain Inventory, and EuroQoL-5Dquestionnaires. Female participants allocated to a chronic cervical (n = 20 and a control group (n = 22. Investigator blindedto the study groups recorded sEMG of bilateral masseter and CE muscles (C4/5 level at rest and during light teeth clenching.Results: No differences in socio-demographic profile; or in masseter or CE sEMG activity at rest or during light clench betweengroups. The pain group had higher scores for pain, reported a daytime teeth clenching habit, and had worse scores for the healthrelatedquality of life (HRQoL sub-sections for pain, anxiety/depression, and lower scores for perceived health status. Conclusion:No relationship established between cervico-mandibular sEMG activity and reported disability in females with chronic cervicaldysfunction and no TM disorder. Association between biopsychosocial factors of teeth clenching and anxiety/depression highlightscomplex pathophysiological mechanisms in chronic recurrent cervical pain.

Follow-up findings in regional cerebral blood flow (r-CBF)-SPECT in a case of idiopathic childhood hemidystonia. Functional neuroimaging and pathophysiological implications

International Nuclear Information System (INIS)

Fiedler, A.; Aderbauer, J.; Segerer, H.; Marienhagen, J.; Bock, E.; Eilles, C.

1999-01-01

A 9 1/2-year-old girl suffered from intermitting tremor and jitteriness of her left hand and oral muscles every 4 to 6 weeks with long lasting episodes. Clinically myoclonias and dystonic positioning of the left arm, hand and facial muscles were seen. No evidence of trauma, infection or inborn errors of metabolism was found. Successful therapy with carbamazepine was initiated while L-DOPA failed. An ictal 99m-Tc-HMPAO-SPECT showed severe asymmetry with focal hyperperfusion of the contralateral right thalamus and basal ganglia as well as of the bifrontal cortex, whereas no anatomical lesions were found by MRI. In contrast, an interictally performed 99m-Tc-HMPAO SPECT showed hypoperfusion or the right thalamus and normalisation of the frontal perfusion under medical treatment. These 99m-Tc-HMPAO-SPECT findings may provide new insights into the localisation and pathophysiological pathways of idiopathic childhood dystonia. (orig.) [de

E2F transcription factor-1 deficiency reduces pathophysiology in the mouse model of Duchenne muscular dystrophy through increased muscle oxidative metabolism.

Science.gov (United States)

Blanchet, Emilie; Annicotte, Jean-Sébastien; Pradelli, Ludivine A; Hugon, Gérald; Matecki, Stéfan; Mornet, Dominique; Rivier, François; Fajas, Lluis

2012-09-01

E2F1 deletion leads to increased mitochondrial number and function, increased body temperature in response to cold and increased resistance to fatigue with exercise. Since E2f1-/- mice show increased muscle performance, we examined the effect of E2f1 genetic inactivation in the mdx background, a mouse model of Duchenne muscular dystrophy (DMD). E2f1-/-;mdx mice demonstrated a strong reduction of physiopathological signs of DMD, including preservation of muscle structure, decreased inflammatory profile, increased utrophin expression, resulting in better endurance and muscle contractile parameters, comparable to normal mdx mice. E2f1 deficiency in the mdx genetic background increased the oxidative metabolic gene program, mitochondrial activity and improved muscle functions. Interestingly, we observed increased E2F1 protein levels in DMD patients, suggesting that E2F1 might represent a promising target for the treatment of DMD.

Pathophysiological study of experimental hydrocephalus with computed tomography (CT) scan

International Nuclear Information System (INIS)

Murata, Takaho

1980-01-01

In order to investigate the pathophysiological changes during a development of hydrocephalus, the observations employing computed tomography (CT) scans and monitorings of intracranial epidural pressure (EDP) were performed in a series of kaolin-induced canine hydrocephalus. According to ''volume index'' of ventricles which was calculated from printed-out CT numbers, great individual variations were recognized in the degree of a ventricular enlargement as well as the rate of EDP. They are thought to be due to the difference in types of hydrocephalus, which have been induced by a discrepancy in the site and degree of an obstruction caused by kaolin. Periventricular lucency (PVL) of various degrees were also detected on CT scans of experimental hydrocephalus. It was always marked in the superolateral angle of frontal horn of the lateral ventricles, and differed in degree from severe to mild. PVLs were distinct in the acute stage with high EDP, and gradually became indistinct and had a tendency to disappear thereafter along with decreased EDP. They immediately disappeared after shunting operation. The pathogenesis of PVL was investigated with histological examinations, as well as by using contrast enhancement, Metrizamide ventriculography, the analysis of linear density profiles, and the measurement of regional cerebral blood flow (rCBF). Consequently, PVLs in hydrocephalus are considered to represent an acute edema or a chronic CSF retention in the periventricular white matter caused by increase of water content. In other words, they are regarded as a sign of present or preceding intraventricular hypertension on CT scan, and may become a clinical indication for shunting operation. (author)

Left Ventricular Geometry In Nigerians With Type II Diabetes Mellitus ...

African Journals Online (AJOL)

Background: Left ventricular hypertrophy is independently associated with increased incidence of cardiovascular disease, cardiovascular and all cause mortality. In a relatively healthy hypertensive adult population, type II diabetes is associated with higher left ventricular mass, concentric left ventricular geometry and lower ...

Assessment of right ventricular function using gated blood pool single photon emission computed tomography in inferior myocardial infarction with or without hemodynamically significant right ventricular infarction

International Nuclear Information System (INIS)

Takahashi, Masaharu

1992-01-01

Right ventricular function was assessed using gated blood pool single photon emission computed tomography (GSPECT) in 10 normal subjects and 14 patients with inferior myocardial infarction. Three-dimensional backbround subtraction was achieved by applying an optimal cut off level. The patient group consisted of 6 patients with definite hemodynamic abnormalities indicative of right ventricular infarction (RVI) and 8 other patients with significant obstructive lesion at the proximal portion of right coronary artery without obvious hemodynamic signs of RVI. Right ventricular regional wall motion abnormalities were demonstrated on GSPECT functional images and the indices of right ventricular function (i.e the right ventricular ejection fraction (RVEF), the right ventricular peak ejection rate (RVPER) and the right ventricular peak filling rate (RVPFR)) were significantly reduced in the patient group, not only in the patients with definite RVI but also in those without hemodynamic signs of RVI, even in the absence of definite hemodynamic signs, when the proximal portion of right coronary artery is obstructed. It is concluded that GSPECT is reliable for the assessment of right ventricular function and regional wall motion, and is also useful for the diagnosis of RVI. (author)

Creating Interactions between Tissue-Engineered Skeletal Muscle and the Peripheral Nervous System.

Science.gov (United States)

Smith, Alec S T; Passey, Samantha L; Martin, Neil R W; Player, Darren J; Mudera, Vivek; Greensmith, Linda; Lewis, Mark P

2016-01-01

Effective models of mammalian tissues must allow and encourage physiologically (mimetic) correct interactions between co-cultured cell types in order to produce culture microenvironments as similar as possible to those that would normally occur in vivo. In the case of skeletal muscle, the development of such a culture model, integrating multiple relevant cell types within a biomimetic scaffold, would be of significant benefit for investigations into the development, functional performance, and pathophysiology of skeletal muscle tissue. Although some work has been published regarding the behaviour of in vitro muscle models co-cultured with organotypic slices of CNS tissue or with stem cell-derived neurospheres, little investigation has so far been made regarding the potential to maintain isolated motor neurons within a 3D biomimetic skeletal muscle culture platform. Here, we review the current state of the art for engineering neuromuscular contacts in vitro and provide original data detailing the development of a 3D collagen-based model for the co-culture of primary muscle cells and motor neurons. The devised culture system promotes increased myoblast differentiation, forming arrays of parallel, aligned myotubes on which areas of nerve-muscle contact can be detected by immunostaining for pre- and post-synaptic proteins. Quantitative RT-PCR results indicate that motor neuron presence has a positive effect on myotube maturation, suggesting neural incorporation influences muscle development and maturation in vitro. The importance of this work is discussed in relation to other published neuromuscular co-culture platforms along with possible future directions for the field. © 2016 S. Karger AG, Basel.

LEFT VENTRICULAR ROTATION, TWIST AND UNTWIST: PHYSIOLOGICAL ROLE AND CLINICAL RELEVANCE

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E. N. Pavlyukova

2015-09-01

Full Text Available The helical ventricular myocardial band of Torrent-Guasp is a new concept, which provides strong grounds for reconciliation of some important aspects in cardiovascular medicine. Oblique fiber orientation provides left ventricular rotation, which in addition to radial thickening and longitudinal shortening, is predicted as an essential component of the effective left ventricular pumping. Left ventricular rotation can be measured in clinical practice noninvasively using echocardiography and this provides new opportunities for the assessment of different aspects of left ventricular mechanical function.

Diagnostic electrocardiographic dyad criteria of emphysema in left ventricular hypertrophy.

Science.gov (United States)

Lanjewar, Swapnil S; Chhabra, Lovely; Chaubey, Vinod K; Joshi, Saurabh; Kulkarni, Ganesh; Kothagundla, Chandrasekhar; Kaul, Sudesh; Spodick, David H

2013-01-01

The electrocardiographic diagnostic dyad of emphysema, namely a combination of the frontal vertical P-vector and a narrow QRS duration, can serve as a quasidiagnostic marker for emphysema, with specificity close to 100%. We postulated that the presence of left ventricular hypertrophy in emphysema may affect the sensitivity of this electrocardiographic criterion given that left ventricular hypertrophy generates prominent left ventricular forces and may increase the QRS duration. We reviewed the electrocardiograms and echocardiograms for 73 patients with emphysema. The patients were divided into two groups based on the presence or absence of echocardiographic evidence of left ventricular hypertrophy. The P-vector, QRS duration, and forced expiratory volume in one second (FEV1) were computed and compared between the two subgroups. There was no statistically significant difference in qualitative lung function (FEV1) between the subgroups. There was no statistically significant difference in mean P-vector between the subgroups. The mean QRS duration was significantly longer in patients with left ventricular hypertrophy as compared with those without left ventricular hypertrophy. The presence of left ventricular hypertrophy may not affect the sensitivity of the P-vector verticalization when used as a lone criterion for diagnosing emphysema. However, the presence of left ventricular hypertrophy may significantly reduce the sensitivity of the electrocardiographic diagnostic dyad in emphysema, as it causes a widening of the QRS duration.

Evaluation of the accuracy of ventricular volume measurement by ultrafast CT

International Nuclear Information System (INIS)

Cui Wei; Dai Ruping; Guo Yuyin

1997-01-01

The authors evaluated the accuracy of ventricular volume measured by ultrafast CT (UFCT); and (2) compared the value of ventricular volume derived from long- and short-axis view. Fourteen human left ventricular casts and 15 right ventricular casts were scanned by Imatron C-150 scanner along both the long- and short-axis. The scan protocol was similar to that used in vivo. Eight 7 mm-thick slices were obtained from each cast for both long- and short-axis views. Ventricular volume was determined by the modified Simpson's rule provided by Inamtron Inc. The actual volumes of the ventricular casts were determined by the amount of water displacement by the cast. The actual volumes for left and right ventricles were 55.57 +- 28.91 ml and 64.23 +- 24.51 ml, respectively, the left and right ventricular volumes determined by UFCT were 66.50 +- 33.04 ml and 76.47 +-28.70 ml from long-axis view, and 60.36 +- 29.90 ml and 75.36 +- 28.73 ml from short-axis view, respectively. The measurements by UFCT were significantly greater than the actual volumes of the casts, both for the left and right ventricles (P 0.990). Both left and right ventricular volumes can be determined by UFCT with identical accuracy for both long- and short-axis views in calculating ventricular volume; however, overestimation of ventricular volume by UFCT should be noted

Thalassemia: Pathophysiology and management. Part A

International Nuclear Information System (INIS)

Fucharoen, S.; Rowley, P.T.; Paul, N.W.

1988-01-01

This book contains papers divided among the following sections: molecular biology and pathogenesis; pathophysiology - molecular and cellular; clinical manifestations and hematologic changes; cardiopulmonary defects and platelet function; hormones and minerals; and infection and immunology

Influence of left ventricular hypertrophy on infarct size and left ventricular ejection fraction in ST-elevation myocardial infarction

International Nuclear Information System (INIS)

Małek, Łukasz A.; Śpiewak, Mateusz; Kłopotowski, Mariusz; Petryka, Joanna; Mazurkiewicz, Łukasz; Kruk, Mariusz; Kępka, Cezary; Miśko, Jolanta; Rużyłło, Witold; Witkowski, Adam

2012-01-01

Background: Left ventricular hypertrophy (LVH) predisposes to larger infarct size, which may be underestimated by the left ventricular ejection fraction (LVEF) due to supranormal systolic performance often present in patients with LVH. The aim of the study was to compare infarct size and LVEF in patients with ST-segment elevation myocardial infarction (STEMI) and increased left ventricular mass on cardiac magnetic resonance (CMR). Methods: The study included unselected group of 52 patients (61 ± 11 years, 69% male) with first STEMI who had CMR after median 5 days from the onset of the event. Left ventricular hypertrophy (LVH) was defined as left ventricular mass index exceeding 95th percentile of references values for age and gender. Infarct size was assessed with means of late gadolinium enhancement (LGE). Results: LVH was found in 16 patients (31%). In comparison to the rest of the group, patients with LVH had higher absolute and relative infarct mass (p = 0.002 and p = 0.02, respectively). LVH was related to higher prevalence of microvascular obstruction and myocardial haemorrhage and higher number of LV segments with transmural necrosis (p = 0.02, p = 0.01 and p = 0.01, respectively). Despite marked difference in the infarct size between both studied subgroups there was no difference in LVEF and mean number of dysfunctional LV segments. Conclusions: Patients with LVH undergoing STEMI have larger infarct size underestimated by the LV systolic performance in comparison to patients without LVH.

Oracle, a novel PDZ-LIM domain protein expressed in heart and skeletal muscle.

Science.gov (United States)

Passier, R; Richardson, J A; Olson, E N

2000-04-01

In order to identify novel genes enriched in adult heart, we performed a subtractive hybridization for genes expressed in mouse heart but not in skeletal muscle. We identified two alternative splicing variants of a novel PDZ-LIM domain protein, which we named Oracle. Both variants contain a PDZ domain at the amino-terminus and three LIM domains at the carboxy-terminus. Highest homology of Oracle was found with the human and rat enigma proteins in the PDZ domain (62 and 61%, respectively) and in the LIM domains (60 and 69%, respectively). By Northern hybridization analysis, we showed that expression is highest in adult mouse heart, low in skeletal muscle and undetectable in other adult mouse tissues. In situ hybridization in mouse embryos confirmed and extended these data by showing high expression of Oracle mRNA in atrial and ventricular myocardial cells from E8.5. From E9.5 low expression of Oracle mRNA was detectable in myotomes. These data suggest a role for Oracle in the early development and function of heart and skeletal muscle.

Ventricular kinetic energy may provide a novel noninvasive way to assess ventricular performance in patients with repaired tetralogy of Fallot.

Science.gov (United States)

Jeong, Daniel; Anagnostopoulos, Petros V; Roldan-Alzate, Alejandro; Srinivasan, Shardha; Schiebler, Mark L; Wieben, Oliver; François, Christopher J

2015-05-01

Ventricular kinetic energy measurements may provide a novel imaging biomarker of declining ventricular efficiency in patients with repaired tetralogy of Fallot. Our purpose was to assess differences in ventricular kinetic energy with 4-dimensional flow magnetic resonance imaging between patients with repaired tetralogy of Fallot and healthy volunteers. Cardiac magnetic resonance, including 4-dimensional flow magnetic resonance imaging, was performed at rest in 10 subjects with repaired tetralogy of Fallot and 9 healthy volunteers using clinical 1.5T and 3T magnetic resonance imaging scanners. Right and left ventricular kinetic energy (KERV and KELV), main pulmonary artery flow (QMPA), and aortic flow (QAO) were quantified using 4-dimensional flow magnetic resonance imaging data. Right and left ventricular size and function were measured using standard cardiac magnetic resonance techniques. Differences in peak systolic KERV and KELV in addition to the QMPA/KERV and QAO/KELV ratios between groups were assessed. Kinetic energy indices were compared with conventional cardiac magnetic resonance parameters. Peak systolic KERV and KELV were higher in patients with repaired tetralogy of Fallot (6.06 ± 2.27 mJ and 3.55 ± 2.12 mJ, respectively) than in healthy volunteers (5.47 ± 2.52 mJ and 2.48 ± 0.75 mJ, respectively), but were not statistically significant (P = .65 and P = .47, respectively). The QMPA/KERV and QAO/KELV ratios were lower in patients with repaired tetralogy of Fallot (7.53 ± 5.37 mL/[cycle mJ] and 9.65 ± 6.61 mL/[cycle mJ], respectively) than in healthy volunteers (19.33 ± 18.52 mL/[cycle mJ] and 35.98 ± 7.66 mL/[cycle mJ], respectively; P tetralogy of Fallot. Quantification of ventricular kinetic energy in patients with repaired tetralogy of Fallot is a new observation. Future studies are needed to determine whether changes in ventricular kinetic energy can provide earlier evidence of ventricular dysfunction and guide future medical and

Right ventricular function: methodologic and clinical considerations in noninvasive scintigraphic assessment

International Nuclear Information System (INIS)

Manno, B.V.; Iskandrian, A.S.; Hakki, A.H.

1984-01-01

Right ventricular function plays an important role in many cardiac disorders. Changes in left ventricular function, right ventricular afterload and preload, cardiac medications and ischemia may affect right ventricular function. Radionuclide ventriculography permits quantitative assessment of regional and global function of the right ventricle. This assessment can be made at rest, during exercise or after pharmacologic interventions. The overlap between right ventricle and right atrium is a major limitation for gated scintigraphic techniques. The use of imaging with newer short-lived radionuclides may permit more accurate and reproducible assessment of right ventricular function by means of the first pass method. Further work in areas related to improvement of techniques and the impact of right ventricular function on prognosis is needed

Race differences in ventricular remodeling and function among college football players.

Science.gov (United States)

Haddad, Francois; Peter, Shanon; Hulme, Olivia; Liang, David; Schnittger, Ingela; Puryear, Josephine; Gomari, Fatemeh A; Finocchiaro, Gherardo; Myers, Jonathan; Froelicher, Victor; Garza, Daniel; Ashley, Euan A

2013-07-01

Athletic training is associated with increases in ventricular mass and volume. Recent studies have shown that left ventricular mass increases proportionally in white athletes with a mass/volume ratio approaching unity. The objective of this study was to compare the proportionality in ventricular remodeling and ventricular function in black versus white National Collegiate Athletic Association Division I football players. From 2008 to 2011, football players at Stanford University underwent cardiovascular screening with a 12-point history and physical examination, electrocardiography, and focused echocardiography. Compared with white players, black players had on average higher left ventricular mass indexes (77 ± 11 vs 71 ± 11 g/m(2), p = 0.009), higher mass/volume ratios (1.18 ± 0.16 vs 1.06 ± 0.09 g/ml, p 1.2. Mass/volume ratio was inversely related to early diastolic tissue Doppler velocity e' (r = -0.50, p football players exhibit more concentric ventricular remodeling, lower early diastolic annular velocities, and increased ventricular voltage compared with white players. Ventricular mass increases proportionally to volume in white players but not in black players. Copyright © 2013 Elsevier Inc. All rights reserved.

A Unified Pathophysiological Construct of Diabetes and its Complications.

Science.gov (United States)

Schwartz, Stanley S; Epstein, Solomon; Corkey, Barbara E; Grant, Struan F A; Gavin Iii, James R; Aguilar, Richard B; Herman, Mary E

2017-09-01

Advances in understanding diabetes mellitus (DM) through basic and clinical research have helped clarify and reunify a disease state fragmented into numerous etiologies and subtypes. It is now understood that a common pathophysiology drives the diabetic state throughout its natural history and across its varied clinical presentations, a pathophysiology involving metabolic insults, oxidative damage, and vicious cycles that aggravate and intensify organ dysfunction and damage. This new understanding of the disease requires that we revisit existing diagnostics and treatment approaches, which were built upon outmoded assumptions. 'The Common Pathophysiologic Origins of Diabetes Mellitus and its Complications Construct' is presented as a more accurate, foundational, and translatable construct of DM that helps make sense of the hitherto ambiguous findings of long-term outcome studies. Copyright © 2017 Elsevier Ltd. All rights reserved.

Myogenin regulates exercise capacity but is dispensable for skeletal muscle regeneration in adult mdx mice.

Directory of Open Access Journals (Sweden)

Eric Meadows

Full Text Available Duchenne muscular dystrophy (DMD is the most prevalent inherited childhood muscle disorder in humans. mdx mice exhibit a similar pathophysiology to the human disorder allowing for an in-depth investigation of DMD. Myogenin, a myogenic regulatory factor, is best known for its role in embryonic myogenesis, but its role in adult muscle maintenance and regeneration is still poorly understood. Here, we generated an mdx:Myog(flox/flox mouse harboring a tamoxifen-inducible Cre recombinase transgene, which was used to conditionally delete Myog during adult life. After tamoxifen treatment, three groups of mice were created to study the effects of Myog deletion: mdx:Myog(flox/flox mice (mdx, Myog(flox/flox mice (wild-type, and mdx:Myog(floxΔ/floxΔ:Cre-ER mice (mdx:Myog-deleted. mdx:Myog-deleted mice exhibited no adverse phenotype and behaved normally. When run to exhaustion, mdx:Myog-deleted mice demonstrated an enhanced capacity for exercise compared to mdx mice, running nearly as far as wild-type mice. Moreover, these mice showed the same signature characteristics of muscle regeneration as mdx mice. Unexpectedly, we found that myogenin was dispensable for muscle regeneration. Factors associated with muscle fatigue, metabolism, and proteolysis were significantly altered in mdx:Myog-deleted mice, and this might contribute to their increased exercise capacity. Our results reveal novel functions for myogenin in adult muscle and suggest that reducing Myog expression in other muscle disease models may partially restore muscle function.

Annular subvalvular left ventricular aneurysm in Bahia, Brazil.

Science.gov (United States)

Guimarães, A C; Filho, A S; Esteves, J P; Abreu, W N; Vinhaes, L A; de Almeida Souza, J A; Machado, A

1976-10-01

Two cases of left ventricular aneurysm, a 16-year-old black boy and a 23-year-old white girl, from Bahia, Brazil, are presented. In both patients there was enlargement of the cardiac silhouette and a prominent bulge of the left inferior border. On the right oblique view a ring of calcium at the ventricular opening of the aneurysms was visualized. A left ventriculogram showed a huge aneurysm in the first case and a bulge on the lateral wall of the left ventricle in the other. Cardiac catheterization showed a rise in left and right ventricular end-diastolic pressures and in the mean pulmonary artery pressure. In the first case the contour of the right ventricular pressure curve showed a restrictive pattern. The similarities of these aneurysms with the annular submitral type described in young black Africans are stressed.

Central-Approach Surgical Repair of Coarctation of the Aorta with a Back-up Left Ventricular Assist Device for an Infant Presenting with Severe Left Ventricular Dysfunction

Directory of Open Access Journals (Sweden)

Tae Hoon Kim

2015-12-01

Full Text Available A two-month-old infant presented with coarctation of the aorta, severe left ventricular dysfunction, and moderate to severe mitral regurgitation. Through median sternotomy, the aortic arch was repaired under cardiopulmonary bypass and regional cerebral perfusion. The patient was postoperatively supported with a left ventricular assist device for five days. Left ventricular function gradually improved, eventually recovering with the concomitant regression of mitral regurgitation. Prompt surgical repair of coarctation of the aorta is indicated for patients with severe left ventricular dysfunction. A central approach for surgical repair with a back-up left ventricular assist device is a safe and effective treatment strategy for these patients.

Central-Approach Surgical Repair of Coarctation of the Aorta with a Back-up Left Ventricular Assist Device for an Infant Presenting with Severe Left Ventricular Dysfunction.

Science.gov (United States)

Kim, Tae Hoon; Shin, Yu Rim; Kim, Young Sam; Kim, Do Jung; Kim, Hyohyun; Shin, Hong Ju; Htut, Aung Thein; Park, Han Ki

2015-12-01

A two-month-old infant presented with coarctation of the aorta, severe left ventricular dysfunction, and moderate to severe mitral regurgitation. Through median sternotomy, the aortic arch was repaired under cardiopulmonary bypass and regional cerebral perfusion. The patient was postoperatively supported with a left ventricular assist device for five days. Left ventricular function gradually improved, eventually recovering with the concomitant regression of mitral regurgitation. Prompt surgical repair of coarctation of the aorta is indicated for patients with severe left ventricular dysfunction. A central approach for surgical repair with a back-up left ventricular assist device is a safe and effective treatment strategy for these patients.

Advanced quantitative echocardiography in arrhythmogenic right ventricular cardiomyopathy

DEFF Research Database (Denmark)

Kjaergaard, Jesper; Hastrup Svendsen, Jesper; Sogaard, Peter

2007-01-01

BACKGROUND: Arrhythmogenic right ventricular (RV) cardiomyopathy (ARVC) is a regional disease of the RV myocardium with variable degrees of left ventricular involvement. Three-dimensional echocardiography and Doppler tissue imaging (DTI) are new echocardiographic modalities for the evaluation......, patients with ARVC had a decreased RV ejection fraction (0.47 +/- 0.08 vs 0.53 +/- 0.05, P vs 15.1 +/- 3.7 cm/s, P left ventricle (7.0 +/- 2.6 vs 9.5 +/- 1.9 cm/s, P ... of the longitudinal motility appears to be a sensitive marker of preclinical left ventricular involvement....

Reversibility of ventricular dysfunction: clinical experience in a medical office

Directory of Open Access Journals (Sweden)

Antonio Carlos Pereira Barretto

2001-12-01

Full Text Available OBJECTIVE - To describe clinical observations of marked improvement in ventricular dysfunction in a medical office environment under circumstances differing from those in study protocols and multicenter studies performed in hospital or with outpatient cohorts. METHODS - Eleven cardiac failure patients with marked ventricular dysfunction receiving treatment at a doctors office between 1994 and 1999 were studied. Their ages ranged from 20 and 66 years (mean 39.42±14.05 years; 7 patients were men, 4 were women. Cardiopathic etiologies were arterial hypertension in 5 patients, peripartum cardiomyopathy in 2, nondefined myocarditis in 2, and alcoholic cardiomyopathy in 4. Initial echocardiograms revealed left ventricular dilatation (average diastolic diameter, 69.45±8.15mm, reduced left ventricular ejection fraction (0.38±0.08 and left atrial dilatation (43.36±5.16mm. The therapeutic approach followed consisted of patient orientation, elimination of etiological or causal factors of cardiac failure, and prescription of digitalis, diuretics, and angiotensinconverting enzyme inhibitors. RESULTS - Following treatment, left ventricular ejection fraction changed to 0.63±0.09; left ventricular diameters changed to 57.18±8.13mm, and left atrium diameters changed to 37.27±8.05mm. Maximum improvement was noted after 16.9±8.63 (6 to 36 months. CONCLUSION - Patients with serious cardiac failure and ventricular dysfunction caused by hypertension, alcoholism, or myocarditis can experience marked improvement in ventricular dysfunction after undergoing appropriate therapy within the venue of the doctor's office.

The measurement of reversible redox dependent post-translational modifications and their regulation of mitochondrial and skeletal muscle function

Directory of Open Access Journals (Sweden)

Philip A Kramer

2015-11-01

Full Text Available Mitochondrial oxidative stress is a common feature of skeletal myopathies across multiple conditions; however, the mechanism by which it contributes to skeletal muscle dysfunction remains controversial. Oxidative damage to proteins, lipids, and DNA has received the most attention, yet an important role for reversible redox post-translational modifications (PTMs in pathophysiology is emerging. The possibility that these PTMs can exert dynamic control of muscle function implicates them as a mechanism contributing to skeletal muscle dysfunction in chronic disease. Herein, we discuss the significance of thiol-based redox dependent modifications to mitochondrial, myofibrillar and excitation-contraction (EC coupling proteins with an emphasis on how these changes could alter skeletal muscle performance under chronically stressed conditions. A major barrier to a better mechanistic understanding of the role of reversible redox PTMs in muscle function is the technical challenges associated with accurately measuring the changes of site-specific redox PTMs. Here we will critically review current approaches with an emphasis on sample preparation artifacts, quantitation, and specificity. Despite these challenges, the ability to accurately quantify reversible redox PTMs is critical to understanding the mechanisms by which mitochondrial oxidative stress contributes to skeletal muscle dysfunction in chronic diseases.

The Measurement of Reversible Redox Dependent Post-translational Modifications and Their Regulation of Mitochondrial and Skeletal Muscle Function

Energy Technology Data Exchange (ETDEWEB)

Kramer, Philip A.; Duan, Jicheng; Qian, Wei-Jun; Marcinek, David J.

2015-11-25

Mitochondrial oxidative stress is a common feature of skeletal myopathies across multiple conditions; however, the mechanism by which it contributes to skeletal muscle dysfunction remains controversial. Oxidative damage to proteins, lipids, and DNA has received the most attention, yet an important role for reversible redox post-translational modifications (PTMs) in pathophysiology is emerging. The possibility that these PTMs can exert dynamic control of muscle function implicates them as a mechanism contributing to skeletal muscle dysfunction in chronic disease. Herein, we discuss the significance of thiol-based redox dependent modifications to mitochondrial, myofibrillar and excitation-contraction (EC) coupling proteins with an emphasis on how these changes could alter skeletal muscle performance under chronically stressed conditions. A major barrier to a better mechanistic understanding of the role of reversible redox PTMs in muscle function is the technical challenges associated with accurately measuring the changes of site-specific redox PTMs. Here we will critically review current approaches with an emphasis on sample preparation artifacts, quantitation, and specificity. Despite these challenges, the ability to accurately quantify reversible redox PTMs is critical to understanding the mechanisms by which mitochondrial oxidative stress contributes to skeletal muscle dysfunction in chronic diseases.

[A case of rupture of the left ventricle free wall with papillary muscle dysfunction following acute myocardial infarction, operated on successfully].

Science.gov (United States)

de Lima, R; Perdigão, C; Neves, L; Cravino, J; Dantas, M; Bordalo, A; Pais, F; Diogo, A N; Ferreira, R; Ribeiro, C

1990-09-01

The authors present a case of left ventricular free wall rupture post acute myocardial infarction, associated with mitral papillary posterior muscle necrosis, operated by infartectomy and mitral valvular protesis replacement. They refer the various complications occurred during the hospital staying, and discuss its medical and surgical approach. The patient was discharged alive and six months after the infarction keeps a moderate activity.

Fatigue as Presenting Symptom and a High Burden of Premature Ventricular Contractions Are Independently Associated With Increased Ventricular Wall Stress in Patients With Normal Left Ventricular Function.

Science.gov (United States)

van Huls van Taxis, Carine F B; Piers, Sebastiaan R D; de Riva Silva, Marta; Dekkers, Olaf M; Pijnappels, Daniël A; Schalij, Martin J; Wijnmaalen, Adrianus P; Zeppenfeld, Katja

2015-12-01

High idiopathic premature ventricular contractions (PVC) burden has been associated with PVC-induced cardiomyopathy. Patients may be symptomatic before left ventricular (LV) dysfunction develops. N-terminal pro-B-type natriuretic peptide (NT-proBNP) and circumferential end-systolic wall stress (cESS) on echocardiography are markers for increased ventricular wall stress. This study aimed to evaluate the relation between presenting symptoms, PVC burden, and increased ventricular wall stress in patients with frequent PVCs and preserved LV function. Eighty-three patients (41 men; 49±15 years) with idiopathic PVCs and normal LV function referred for PVC ablation were included. Type of symptoms (palpitations, fatigue, and [near-]syncope), PVC burden on 24-hour Holter, NT-proBNP levels, and cESS on echocardiography were assessed before and 3 months after ablation. Sustained successful ablation was defined as ≥80% PVC burden reduction during follow-up. Patients were symptomatic for 24 months (Q1-Q3, 16-60); 73% reported palpitations, 47% fatigue, and 30% (near-)syncope. Baseline PVC burden was 23±13%, median NT-proBNP 92 pg/mL (Q1-Q3 50-156), and cESS 143±35 kdyne/cm(2). Fatigue was associated with higher baseline NT-proBNP and cESS (PFatigue was independently associated with a significantly larger reduction in NT-proBNP. In patients with nonsuccessful ablation, NT-proBNP and cESS remained unchanged. In patients with frequent PVCs and preserved LV function, fatigue was associated with higher baseline NT-proBNP and cESS, and with a significantly larger reduction in NT-proBNP after sustained successful ablation. These findings support a link between fatigue and PVC-induced increased ventricular wall stress, despite preserved LV function. © 2015 American Heart Association, Inc.

Clinical use of ultrashort-lived radionuclide krypton-81m for noninvasive analysis of right ventricular performance in normal subjects and patients with right ventricular dysfunction

International Nuclear Information System (INIS)

Nienaber, C.A.; Spielmann, R.P.; Wasmus, G.; Mathey, D.G.; Montz, R.; Bleifeld, W.H.

1985-01-01

The ultrashort-lived radionuclide krypton-81m, eluted in 5% dextrose from a bedside rubidium-81m generator, was intravenously infused for rapid imaging of the right-sided heart chambers in the right anterior oblique projection adjusted for optimal right atrioventricular separation. Left-sided heart and lung background was minimized by rapid decay and efficient exhalation of krypton-81m, requiring no algorithm for background correction. A double region of interest method decreased the variability in the assessment of ejection fraction to 5%. In 10 normal subjects, 11 patients with pulmonary hypertension, 4 patients with right ventricular outflow tract obstruction and 4 patients with right ventricular infarction, right ventricular ejection fraction determined by krypton-81m equilibrium blood pool imaging ranged from 14 to 76%. The correlation between these values and those determined by cineangiography according to Simpson's rule was close: r . 0.93 for all data points, r . 0.92 for studies at rest and r . 0.93 for exercise studies. Exercise-related changes in right ventricular function revealed a disturbed functional reserve with pulmonary hypertension and right ventricular infarction, whereas in compensated right ventricular outflow tract obstruction there was a physiologic increase in ejection fraction with exercise. Thus, equilibrium-gated right ventricular imaging using ultrashort-lived krypton-81m is a simple, accurate and reproducible method with potential for serial assessment of right ventricular ejection fraction in a variety of right ventricular anatomic and functional abnormalities, both at rest and during exercise. Advantages of this method include an extremely low radiation dose to patients and clear right atrioventricular separation without the need to correct for background activity

Videodensitometric assessment of right and left ventricular functions by digital subtraction angiography

International Nuclear Information System (INIS)

Ikeda, Hisao; Yoshiga, Osamu; Shibao, Keigo

1987-01-01

Intravenous digital subtraction (DS) ventriculography was performed in a series of 50 patients with heart diseases to determine right and left ventricular volumes and systolic indices. Right ventricular volume and right ventricular ejection fraction obtained by DS ventriculography were well correlated with those by geometric methods. In 43 patients with left ventricular ejection fraction of 55 % or greater, end-diastolic volume, stroke volume, and ejection fraction in the right ventricle did not differ from those in the left ventricle ; however, both the 1/3 ejection fraction and the peak ejection rate of the right ventricle were significantly lower than those of the left ventricle, suggesting the different modes of left and right ventricular contraction. In the other seven patients with chronic left ventricular failure, right ventricular systolic function may be preserved, even when left ventricular function is severely impaired. Digital subtraction ventriculography has proved to be a simple, useful method in the quanlitative and quantitative assessments of the right and left ventricles. (Namekawa, K.)

Electrical Signs predictors of malignant ventricular arrhythmias

International Nuclear Information System (INIS)

Aleman Fernandez, Ailema Amelia; Dorantes Sanchez, Margarita

2012-01-01

Recurrence of malignant ventricular arrhythmia is frequent in cardioverter-defibrillators related patients. The risk stratification is difficult, there are numerous electrocardiographic predictors but his sensibility and specificity are not absolute. The limit between normal and pathological is not defined, besides the complexity of ventricular arrhythmias. We expose different electrocardiographic predictors that can help to better individual risk stratification

Nonischemic Left Ventricular Scar as a Substrate of Life-Threatening Ventricular Arrhythmias and Sudden Cardiac Death in Competitive Athletes.

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Zorzi, Alessandro; Perazzolo Marra, Martina; Rigato, Ilaria; De Lazzari, Manuel; Susana, Angela; Niero, Alice; Pilichou, Kalliopi; Migliore, Federico; Rizzo, Stefania; Giorgi, Benedetta; De Conti, Giorgio; Sarto, Patrizio; Serratosa, Luis; Patrizi, Giampiero; De Maria, Elia; Pelliccia, Antonio; Basso, Cristina; Schiavon, Maurizio; Bauce, Barbara; Iliceto, Sabino; Thiene, Gaetano; Corrado, Domenico

2016-07-01

The clinical profile and arrhythmic outcome of competitive athletes with isolated nonischemic left ventricular (LV) scar as evidenced by contrast-enhanced cardiac magnetic resonance remain to be elucidated. We compared 35 athletes (80% men, age: 14-48 years) with ventricular arrhythmias and isolated LV subepicardial/midmyocardial late gadolinium enhancement (LGE) on contrast-enhanced cardiac magnetic resonance (group A) with 38 athletes with ventricular arrhythmias and no LGE (group B) and 40 healthy control athletes (group C). A stria LGE pattern with subepicardial/midmyocardial distribution, mostly involving the lateral LV wall, was found in 27 (77%) of group A versus 0 controls (group C; P<0.001), whereas a spotty pattern of LGE localized at the junction of the right ventricle to the septum was respectively observed in 11 (31%) versus 10 (25%; P=0.52). All athletes with stria pattern showed ventricular arrhythmias with a predominant right bundle branch block morphology, 13 of 27 (48%) showed ECG repolarization abnormalities, and 5 of 27 (19%) showed echocardiographic hypokinesis of the lateral LV wall. The majority of athletes with no or spotty LGE pattern had ventricular arrhythmias with a predominant left bundle branch block morphology and no ECG or echocardiographic abnormalities. During a follow-up of 38±25 months, 6 of 27 (22%) athletes with stria pattern experienced malignant arrhythmic events such as appropriate implantable cardiac defibrillator shock (n=4), sustained ventricular tachycardia (n=1), or sudden death (n=1), compared with none of athletes with no or LGE spotty pattern and controls. Isolated nonischemic LV LGE with a stria pattern may be associated with life-threatening arrhythmias and sudden death in the athlete. Because of its subepicardial/midmyocardial location, LV scar is often not detected by echocardiography. © 2016 The Authors.

Adjustable, physiological ventricular restraint improves left ventricular mechanics and reduces dilatation in an ovine model of chronic heart failure.

Science.gov (United States)

Ghanta, Ravi K; Rangaraj, Aravind; Umakanthan, Ramanan; Lee, Lawrence; Laurence, Rita G; Fox, John A; Bolman, R Morton; Cohn, Lawrence H; Chen, Frederick Y

2007-03-13

Ventricular restraint is a nontransplantation surgical treatment for heart failure. The effect of varying restraint level on left ventricular (LV) mechanics and remodeling is not known. We hypothesized that restraint level may affect therapy efficacy. We studied the immediate effect of varying restraint levels in an ovine heart failure model. We then studied the long-term effect of restraint applied over a 2-month period. Restraint level was quantified by use of fluid-filled epicardial balloons placed around the ventricles and measurement of balloon luminal pressure at end diastole. At 4 different restraint levels (0, 3, 5, and 8 mm Hg), transmural myocardial pressure (P(tm)) and indices of myocardial oxygen consumption (MVO2) were determined in control (n=5) and ovine heart failure (n=5). Ventricular restraint therapy decreased P(tm) and MVO2, and improved mechanical efficiency. An optimal physiological restraint level of 3 mm Hg was identified to maximize improvement without an adverse affect on systemic hemodynamics. At this optimal level, end-diastolic P(tm) and MVO2 indices decreased by 27% and 20%, respectively. The serial longitudinal effects of optimized ventricular restraint were then evaluated in ovine heart failure with (n=3) and without (n=3) restraint over 2 months. Optimized ventricular restraint prevented and reversed pathological LV dilatation (130+/-22 mL to 91+/-18 mL) and improved LV ejection fraction (27+/-3% to 43+/-5%). Measured restraint level decreased over time as the LV became smaller, and reverse remodeling slowed. Ventricular restraint level affects the degree of decrease in P(tm), the degree of decrease in MVO2, and the rate of LV reverse remodeling. Periodic physiological adjustments of restraint level may be required for optimal restraint therapy efficacy.

Double stranded viral RNA induces inflammation and insulin resistance in skeletal muscle from pregnant women in vitro.

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Lappas, Martha

2015-05-01

Maternal peripheral insulin resistance and increased inflammation are two features of pregnancies complicated by pre-existing maternal obesity and gestational diabetes mellitus (GDM). There is now increasing evidence that activation of Toll-like receptor (TLR) signalling pathways by viral products may play a role in the pathophysiology of diabetes. Thus, the aim of this study was to assess the effect of the TLR3 ligand and viral dsRNA analogue polyinosinic polycytidilic acid (poly(I:C)) on inflammation and the insulin signalling pathway in skeletal muscle from pregnant women. Human skeletal muscle tissue explants were performed to determine the effect of poly(I:C) on the expression and secretion of markers of inflammation, and the insulin signalling pathway and glucose uptake. Poly(I:C) significantly increased the expression of a number of inflammatory markers in skeletal muscle from pregnant women. Specifically, there was an increase in the expression and/or secretion of the pro-inflammatory cytokines TNF-α, and IL-6 and the pro-inflammatory chemokines IL-8 and MCP-1. These effect of poly(I:C) appear to mediated via a number of signalling molecules including the pro-inflammatory transcription factor NF-κB, and the serine threonine kinases GSK3 and AMPKα. Additionally, poly(I:C) decreased insulin stimulated GLUT-4 expression and glucose uptake in skeletal muscle from pregnant women. The in vitro data presented in this study suggests that viral infection may contribute to the pathophysiology of pregnancies complicated by pre-existing maternal obesity and/or GDM. It should be noted that the in vitro studies cannot be directly used to infer the same outcomes in the intact subject. Copyright © 2015 Elsevier Inc. All rights reserved.

Radionuclide evaluation of left ventricular function with nonimaging probes.

Science.gov (United States)

Wexler, J P; Blaufox, M D

1979-10-01

Portable nonimaging probes have been developed that can evaluate left ventricular function using radionuclide techniques. Two modes of data acquisition are possible with these probe systems, first-pass and gated. Precordial radiocardiograms obtained after a bolus injection can be used to determine cardiac output, pulmonary transit time, pulmonary blood volume, left ventricle ejection fraction, and left-to-right shunts. Gated techniques can be used to determine left ventricular ejection fraction and sytolic time intervals. Probe-determined indices of left ventricular function agree excellently with comparable measurements determined by conventional camera-computer methods as well as by invasive techniques. These have begun to be used in a preliminary manner in a variety of clinical problems associated with left ventricular dysfunction. This review discusses the types of probe systems available, the methods used in positioning them, and details the specifics of their data acquisition and processing capacity. The major criticisms of probe methods are that they are nonimaging and that they measure global rather than regional left ventricular function. In spite of these criticisms, probe systems, because of their portability, high sensitivity, and relatively low cost are useful supplements to conventional camera-computer systems for the measurement of parameters of left ventricular performance using radionuclide techniques.

Ventricular Arrhythmic Storm after Initiating Sacubitril/Valsartan.

Science.gov (United States)

Vicent, Lourdes; Juárez, Miriam; Martín, Irene; García, Jorge; González-Saldívar, Hugo; Bruña, Vanesa; Devesa, Carolina; Sousa-Casasnovas, Iago; Fernández-Avilés, Francisco; Martínez-Sellés, Manuel

Sacubitril/valsartan was approved recently for the treatment of patients with heart failure and reduced ejection fraction. We present 6 cases of ventricular arrhythmia, that occurred shortly after sacubitril/valsartan initiation, that required drug withdrawal. Other potential triggering factors of electrical storm were ruled out and, from the arrhythmic perspective, all of the patients were stable in the previous year. Our aim is to describe the possible association of sacubitril/valsartan with arrhythmic storm. This was an observational monocentric study performed in the first 7 months of sacubitril/valsartan commercialization in Spain (October 2016). All patients were included in the SUMA (Sacubitril/Varsartan Usado Ambulatoriamente en Madrid [Sacubitril/Valsartan Used in Outpatients in Madrid]) registry. Patients were consecutively enrolled on the day they started the drug. Ventricular arrhythmic storm was defined as ≥2 episodes of sustained ventricular arrhythmia or defibrillator therapy application in 24 h. From 108 patients who received the drug, 6 presented with ventricular arrhythmic storm (5.6%). Baseline characteristics were similar in the patients with and without ventricular arrhythmic storm. The total number of days that sacubitril/valsartan was administered to each patient was 5, 6, 44 (8 since titration), 84, 93, and 136 (105 since titration), respectively. Our data are not enough to infer a cause-and-effect relationship. Further investigations regarding a potential proarrhythmic effect of sacubitril/valsartan are probably needed. © 2018 S. Karger AG, Basel.

Isometric exercise: cardiovascular responses in normal and cardiac populations.

Science.gov (United States)

Hanson, P; Nagle, F

1987-05-01

Isometric exercise produces a characteristic pressor increase in blood pressure which may be important in maintaining perfusion of muscle during sustained contraction. This response is mediated by combined central and peripheral afferent input to medullary cardiovascular centers. In normal individuals the increase in blood pressure is mediated by a rise in cardiac output with little or no change in systemic vascular resistance. However, the pressor response is also maintained during pharmacologic blockade or surgical denervation by increasing systemic vascular resistance. Left ventricular function is normally maintained or improves in normal subjects and cardiac patients with mild impairment of left ventricular contractility. Patients with poor left ventricular function may show deterioration during isometric exercise, although this pattern of response is difficult to predict from resting studies. Recent studies have shown that patients with uncomplicated myocardial infarction can perform submaximum isometric exercise such as carrying weights in the range of 30 to 50 lb without difficulty or adverse responses. In addition, many patients who show ischemic ST depression or angina during dynamic exercise may have a reduced ischemic response during isometric or combined isometric and dynamic exercise. Isometric exercises are frequently encountered in activities of daily living and many occupational tasks. Cardiac patients should be gradually exposed to submaximum isometric training in supervised cardiac rehabilitation programs. Specific job tasks that require isometric or combined isometric and dynamic activities may be evaluated by work simulation studies. This approach to cardiac rehabilitation may facilitate patients who wish to return to a job requiring frequent isometric muscle contraction. Finally, there is a need for additional research on the long-term effects of isometric exercise training on left ventricular hypertrophy and performance. The vigorous training

Assessment of inter-atrial, inter-ventricular, and atrio-ventricular interactions in tetralogy of Fallot patients after surgical correction. Insights from two-dimensional speckle tracking and three-dimensional echocardiography.

Science.gov (United States)

Abd El Rahman, Mohamed; Raedle-Hurst, Tanja; Rentzsch, Axel; Schäfers, Hans-Joachim; Abdul-Khaliq, Hashim

2015-10-01

We aimed to assess biatrial size and function, interactions on atrial and ventricular levels, and atrio-ventricular coupling in patients after tetralogy of Fallot repair. A total of 34 patients with a mean age of 20.9±9 years, and 35 healthy controls, underwent two-dimensional speckle tracking echocardiography for ventricular and atrial strain measurements and real-time three-dimensional echocardiography to assess ventricular and atrial volumes. When compared with controls, tetralogy of Fallot patients had significantly reduced right atrial peak atrial longitudinal strain (ptetralogy of Fallot group, left ventricular ejection fraction was negatively related to the right ventricular end-systolic volume normalised to body surface area (r=-0.62, ptetralogy of Fallot patients, biatrial dysfunction exists and can be quantified via two-dimensional speckle tracking echocardiography as well as real-time three-dimensional echocardiography. Different forms of interactions on atrial and ventricular levels are evident among such cohorts.

Lumbar paraspinal muscle transverse area and symmetry in dogs with and without degenerative lumbosacral stenosis.

Science.gov (United States)

Henderson, A L; Hecht, S; Millis, D L

2015-10-01

To investigate whether dogs with degenerative lumbosacral stenosis have decreased lumbar paraspinal muscle transverse area and symmetry compared with control dogs. Retrospective cross-sectional study comparing muscles in transverse T2-weighted magnetic resonance images for nine dogs with and nine dogs without degenerative -lumbosacral stenosis. Mean transverse area was measured for the lumbar multifidus and sacrocaudalis dorsalis lateralis muscles bilaterally and the L7 vertebral body at the level of the caudal endplate. Transverse areas of both muscle groups relative to L7 and asymmetry indices were compared between study populations using independent t tests. Mean muscle-to-L7 transverse area ratios were significantly smaller in the degenerative lumbosacral stenosis group compared with those in the control group in both lumbar multifidus (0·84 ±0·26 versus 1·09 ±0·25; P=0·027) and sacrocaudalis dorsalis lateralis (0·5 ±0·15 versus 0·68 ±0·12; P=0·005) muscles. Mean asymmetry indices were higher for both muscles in the group with degenerative lumbosacral stenosis than in the control group, but highly variable and the difference was not statistically significant. These findings suggest that dogs with degenerative lumbosacral stenosis have decreased lumbar paraspinal muscle mass that may be a cause or consequence of the -syndrome. Understanding altered paraspinal muscle characteristics may improve understanding of the -pathophysiology and management options for degenerative lumbosacral stenosis. © 2015 British Small Animal Veterinary Association.

Diagnostic electrocardiographic dyad criteria of emphysema in left ventricular hypertrophy

Directory of Open Access Journals (Sweden)

Lanjewar SS

2013-11-01

Full Text Available Swapnil S Lanjewar,1 Lovely Chhabra,1 Vinod K Chaubey,1 Saurabh Joshi,1 Ganesh Kulkarni,1 Chandrasekhar Kothagundla,1 Sudesh Kaul,1 David H Spodick21Department of Internal Medicine, 2Department of Cardiovascular Medicine, Saint Vincent Hospital, University of Massachusetts Medical School, Worcester, MA, USABackground: The electrocardiographic diagnostic dyad of emphysema, namely a combination of the frontal vertical P-vector and a narrow QRS duration, can serve as a quasidiagnostic marker for emphysema, with specificity close to 100%. We postulated that the presence of left ventricular hypertrophy in emphysema may affect the sensitivity of this electrocardiographic criterion given that left ventricular hypertrophy generates prominent left ventricular forces and may increase the QRS duration.Methods: We reviewed the electrocardiograms and echocardiograms for 73 patients with emphysema. The patients were divided into two groups based on the presence or absence of echocardiographic evidence of left ventricular hypertrophy. The P-vector, QRS duration, and forced expiratory volume in one second (FEV1 were computed and compared between the two subgroups.Results: There was no statistically significant difference in qualitative lung function (FEV1 between the subgroups. There was no statistically significant difference in mean P-vector between the subgroups. The mean QRS duration was significantly longer in patients with left ventricular hypertrophy as compared with those without left ventricular hypertrophy.Conclusion: The presence of left ventricular hypertrophy may not affect the sensitivity of the P-vector verticalization when used as a lone criterion for diagnosing emphysema. However, the presence of left ventricular hypertrophy may significantly reduce the sensitivity of the electrocardiographic diagnostic dyad in emphysema, as it causes a widening of the QRS duration.Keywords: emphysema, electrocardiogram, left ventricular hypertrophy, chronic

[Idiopathic ventricular arrhythmia in children. Apropos of 24 cases].

Science.gov (United States)

Coeurderoy, A; Almange, C; Laurent, M; Biron, Y; Leborgne, P

1985-12-01

The severity and prognosis of idiopathic ventricular arrhythmias in childhood were studied in 24 patients (12 boys, 12 girls) with an average age of 8 years at the time of diagnosis of the arrhythmia. Investigations included clinical assessment and analysis of basal ECG (morphology of the arrhythmias) and dynamic recordings (Holter and exercise stress testing). The clinical course was followed for an average of 3.8 years. The patients were classified in two groups: monomorphic arrhythmias (Group I) and polymorphic arrhythmias (Group II). Group I was divided into 4 subgroups: isolated ventricular extrasystoles (IA), 11 patients; ventricular extrasystoles with bursts of ventricular tachycardia (IB), 6 patients; sustained ventricular tachycardia without intercritical extrasystoles (IC), 1 patient; accelerated idioventricular rhythm (ID), 2 patients. Subgroups IA, IB and ID were characterised by the absence of symptoms, the disappearance of the arrhythmia on exercise, the decreased efficacy of antiarrhythmic drugs and an excellent prognosis. Therapeutic abstention was the rule in these patients. Patients in Group IC were characterised by the variability of their symptoms, the absence of exercise induced arrhythmias, the need for treatment in most cases and a good long-term prognosis. Group II was divided into 2 subgroups: adrenergic polymorphic ventricular tachycardia (IIA), 2 patients, and non-adrenergic polymorphic ventricular tachycardia (IIB), 2 patients. Patients in Subgroup IIA were characterised by syncope on exercise or emotion, the need for betablocker therapy which considerably improved the patients symptoms but which did not usually prevent sudden death.(ABSTRACT TRUNCATED AT 250 WORDS)

Left ventricular dysfunction after closure of large patent ductus arteriosus.

Science.gov (United States)

Galal, M Omar; Amin, Mohamed; Hussein, Arif; Kouatli, Amjad; Al-Ata, Jameel; Jamjoom, Ahmed

2005-03-01

Changes in left ventricular dimensions and performance were studied in 43 patients after transcatheter occlusion or surgical ligation of patent ductus arteriosus. The patients were assigned to 2 groups based on their ductal diameter: >/= 3.1 mm to group A (n = 27) and ventricular end-diastolic diameter than group B, while all patients had normal shortening fraction and ejection fraction. Within 1 month after intervention, left ventricular end-diastolic diameter showed a trend towards regression while shortening fraction and ejection fraction decreased significantly in group A. There were no significant changes in these parameters in group B. Between 1 and 6 months after intervention, left ventricular performance improved in most of the group A patients who were followed up. We conclude that closure of large ductus arteriosus in children leads to significant immediate deterioration of left ventricular performance, which appears to recover within a few months. Echocardiographic study before hospital discharge is recommended in these patients. Serious deterioration of ventricular performance after closure may warrant the use of angiotensin converting enzyme inhibitors.

Hypertension in women--pathophysiological and clinical aspects.

Science.gov (United States)

Erdine, Serap; Arslan, Eren; Olszanecka, Agnieszka

2012-01-01

Hypertension is the most important risk factor, responsible for cardiovascular morbidity and mortality worldwide, both in men and women. Cardiovascular disorders in women are still underestimated, due to lower absolute risk calculations and the underdetection of classical risk factors. In recent years the differences in pathophysiology and the clinical presentation and treatment of cardiac diseases in women have become fields of interest and research. Several studies have examined gender-related differences in the pathophysiology of hypertension, its prevalence and control. The influence of menopause, obesity and salt-sensitivity on the pathogenesis of hypertension in women has been widely investigated. This article presents current data on differences in prevalence, control and mechanisms of hypertension in women.

Polycystic Ovary Syndrome, Insulin Resistance, and Obesity: Navigating the Pathophysiologic Labyrinth

Science.gov (United States)

Rojas, Joselyn; Chávez, Mervin; Olivar, Luis; Rojas, Milagros; Morillo, Jessenia; Mejías, José; Calvo, María; Bermúdez, Valmore

2014-01-01

Polycystic ovary syndrome (PCOS) is a highly prevalent endocrine-metabolic disorder that implies various severe consequences to female health, including alarming rates of infertility. Although its exact etiology remains elusive, it is known to feature several hormonal disturbances, including hyperandrogenemia, insulin resistance (IR), and hyperinsulinemia. Insulin appears to disrupt all components of the hypothalamus-hypophysis-ovary axis, and ovarian tissue insulin resistance results in impaired metabolic signaling but intact mitogenic and steroidogenic activity, favoring hyperandrogenemia, which appears to be the main culprit of the clinical picture in PCOS. In turn, androgens may lead back to IR by increasing levels of free fatty acids and modifying muscle tissue composition and functionality, perpetuating this IR-hyperinsulinemia-hyperandrogenemia cycle. Nonobese women with PCOS showcase several differential features, with unique biochemical and hormonal profiles. Nevertheless, lean and obese patients have chronic inflammation mediating the long term cardiometabolic complications and comorbidities observed in women with PCOS, including dyslipidemia, metabolic syndrome, type 2 diabetes mellitus, and cardiovascular disease. Given these severe implications, it is important to thoroughly understand the pathophysiologic interconnections underlying PCOS, in order to provide superior therapeutic strategies and warrant improved quality of life to women with this syndrome. PMID:25763405

Polycystic Ovary Syndrome, Insulin Resistance, and Obesity: Navigating the Pathophysiologic Labyrinth

Directory of Open Access Journals (Sweden)

Joselyn Rojas

2014-01-01

Full Text Available Polycystic ovary syndrome (PCOS is a highly prevalent endocrine-metabolic disorder that implies various severe consequences to female health, including alarming rates of infertility. Although its exact etiology remains elusive, it is known to feature several hormonal disturbances, including hyperandrogenemia, insulin resistance (IR, and hyperinsulinemia. Insulin appears to disrupt all components of the hypothalamus-hypophysis-ovary axis, and ovarian tissue insulin resistance results in impaired metabolic signaling but intact mitogenic and steroidogenic activity, favoring hyperandrogenemia, which appears to be the main culprit of the clinical picture in PCOS. In turn, androgens may lead back to IR by increasing levels of free fatty acids and modifying muscle tissue composition and functionality, perpetuating this IR-hyperinsulinemia-hyperandrogenemia cycle. Nonobese women with PCOS showcase several differential features, with unique biochemical and hormonal profiles. Nevertheless, lean and obese patients have chronic inflammation mediating the long term cardiometabolic complications and comorbidities observed in women with PCOS, including dyslipidemia, metabolic syndrome, type 2 diabetes mellitus, and cardiovascular disease. Given these severe implications, it is important to thoroughly understand the pathophysiologic interconnections underlying PCOS, in order to provide superior therapeutic strategies and warrant improved quality of life to women with this syndrome.

Polycystic ovary syndrome, insulin resistance, and obesity: navigating the pathophysiologic labyrinth.

Science.gov (United States)

Rojas, Joselyn; Chávez, Mervin; Olivar, Luis; Rojas, Milagros; Morillo, Jessenia; Mejías, José; Calvo, María; Bermúdez, Valmore

2014-01-01

Polycystic ovary syndrome (PCOS) is a highly prevalent endocrine-metabolic disorder that implies various severe consequences to female health, including alarming rates of infertility. Although its exact etiology remains elusive, it is known to feature several hormonal disturbances, including hyperandrogenemia, insulin resistance (IR), and hyperinsulinemia. Insulin appears to disrupt all components of the hypothalamus-hypophysis-ovary axis, and ovarian tissue insulin resistance results in impaired metabolic signaling but intact mitogenic and steroidogenic activity, favoring hyperandrogenemia, which appears to be the main culprit of the clinical picture in PCOS. In turn, androgens may lead back to IR by increasing levels of free fatty acids and modifying muscle tissue composition and functionality, perpetuating this IR-hyperinsulinemia-hyperandrogenemia cycle. Nonobese women with PCOS showcase several differential features, with unique biochemical and hormonal profiles. Nevertheless, lean and obese patients have chronic inflammation mediating the long term cardiometabolic complications and comorbidities observed in women with PCOS, including dyslipidemia, metabolic syndrome, type 2 diabetes mellitus, and cardiovascular disease. Given these severe implications, it is important to thoroughly understand the pathophysiologic interconnections underlying PCOS, in order to provide superior therapeutic strategies and warrant improved quality of life to women with this syndrome.

Pharmacogenetics and pathophysiology of CACNA1S mutations in malignant hyperthermia.

Science.gov (United States)

Beam, Teresa A; Loudermilk, Emily F; Kisor, David F

2017-02-01

A review of the pharmacogenetics (PGt) and pathophysiology of calcium voltage-gated channel subunit alpha1 S (CACNA1S) mutations in malignant hyperthermia susceptibility type 5 (MHS5; MIM #60188) is presented. Malignant hyperthermia (MH) is a life-threatening hypermetabolic state of skeletal muscle usually induced by volatile, halogenated anesthetics and/or the depolarizing neuromuscular blocker succinylcholine. In addition to ryanodine receptor 1 (RYR1) mutations, several CACNA1S mutations are known to be risk factors for increased susceptibility to MH (MHS). However, the presence of these pathogenic CACNA1S gene variations cannot be used to positively predict MH since the condition is genetically heterogeneous with variable expression and incomplete penetrance. At present, one or at most six CACNA1S mutations display significant linkage or association either to clinically diagnosed MH or to MHS as determined by contracture testing. Additional pathogenic variants in CACNA1S, either alone or in combination with genes affecting Ca 2+ homeostasis, are likely to be discovered in association to MH as whole exome sequencing becomes more commonplace. Copyright © 2017 the American Physiological Society.

A case of appropriate inappropriate device therapy: Hyperkalemia-induced ventricular oversensing

Science.gov (United States)

Oudit, Gavin Y; Cameron, Doug; Harris, Louise

2008-01-01

The present case describes a patient who received inappropriate, but potentially life-saving, therapy from her implantable cardioverter defibrillator (ICD) in the setting of acute hyperkalemia (plasma potassium concentration = 8 mM). Hyperkalemia was associated with the development of a slow sinusoidal ventricular tachycardia, at a rate of 100 beats/min to 125 beats/min (610 ms to 480 ms) in a patient who is pacemaker-dependent. There was associated fractionation of the ICD electrogram and T wave oversensing, leading to ventricular oversensing with resultant detection in the ventricular fibrillation rate zone. This was followed by shock therapy, even though the ventricular tachycardia rate was below the programmed detection rate of the ICD. The subsequent emergency treatment of the hyperkalemia normalized the electrogram, corrected the ventricular oversensing and arrhythmia, and restored rate-adaptive single-chamber ventricular pacing. PMID:18340383

Differential diagnosis of the 4th ventricular tumors

International Nuclear Information System (INIS)

Lee, Sang Woo; Lee, Jong Min; Kang, Moo Song; Kim, Chul Min; Kim, Chang Soo

1997-01-01

To determine by analysis of MR and CT findings the points of differentiation among 4th ventricular tumors, especially the change of shape of the 4th ventricle caused by the site at which 4th ventricular tumors originate. The authors retrospectively analyzed and compared the CT(n=5) and MRI(n=12) findings of 13 pathologically proven 4th ventricular tumors comprising six medulloblastomas three ependymomas(4 cases) and three choroids plexus papillomas. On axial MRI medulloblastomas showed anterior and anterolateral CSF-clefts between the tumor mass and the 4th ventricular wall in one and five cases, respectively; on sagittal MRI, anterior beaking of the upper 4th ventricle was seen. Two ependymomas showed posterolateral CSF-cleft on axial MRI and posterior beaking of the upper 4th ventricle on sagittal MRI. Two ependymomas and all choroids plexus papillomas showed anterior, posterior and lateral CSF-clefts on axial MRI, and anterior and posterior beakings of the upper 4th ventricle on sagittal MRI. On Gd-DTPA enhanced T1WI, all medulloblastomas and ependymomas showed inhomogeneous enhancement, and all choroids plexus papillomas showed homogeneous enhancement. On CT, tow choroids plexus papillomas showed dense calcifications. The differential diagnosis of 4th ventricular tumors can be preoperatively suggested by analysis of findings such as a CSF-cleft between the tumor mass and the 4th ventricular wall on axial MR and CT images, the shape of the upper 4th ventricle on sagittal MRI, contrast enhancement pattern, necrosis and cyst, and CSF seeding

Relation between N-terminal pro-brain natriuretic peptide and cardiac remodeling and function assessed by cardiovascular magnetic resonance imaging in patients with arrhythmogenic right ventricular cardiomyopathy.

Science.gov (United States)

Cheng, Huaibing; Lu, Minjie; Hou, Cuihong; Chen, Xuhua; Wang, Jing; Yin, Gang; Chu, Jianmin; Zhang, Shu; Prasad, Sanjay K; Pu, Jielin; Zhao, Shihua

2015-02-01

Although N-terminal pro-brain natriuretic peptide (NT-proBNP) is a useful screening test of impaired right ventricular (RV) function in conditions affecting the right-sided cardiac muscle, the role of NT-proBNP remains unclear in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). This study was designed to clarify the relation between the plasma NT-proBNP level and the RV function evaluated by cardiovascular magnetic resonance (CMR) imaging. We selected 56 patients with confirmed ARVC only when their blood specimens for NT-proBNP measurements were collected within 48 hours of a CMR scan. The NT-proBNP level was significantly higher in patients with RV dysfunction than in patients without RV dysfunction (median of 655.3 [interquartile range 556.4 to 870.0] vs 347.0 [interquartile range 308.0 to 456.2] pmol/L, p rights reserved.

Usefulness of ventricular endocardial electric reconstruction from body surface potential maps to noninvasively localize ventricular ectopic activity in patients

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Lai, Dakun; Sun, Jian; Li, Yigang; He, Bin

2013-06-01

As radio frequency (RF) catheter ablation becomes increasingly prevalent in the management of ventricular arrhythmia in patients, an accurate and rapid determination of the arrhythmogenic site is of important clinical interest. The aim of this study was to test the hypothesis that the inversely reconstructed ventricular endocardial current density distribution from body surface potential maps (BSPMs) can localize the regions critical for maintenance of a ventricular ectopic activity. Patients with isolated and monomorphic premature ventricular contractions (PVCs) were investigated by noninvasive BSPMs and subsequent invasive catheter mapping and ablation. Equivalent current density (CD) reconstruction (CDR) during symptomatic PVCs was obtained on the endocardial ventricular surface in six patients (four men, two women, years 23-77), and the origin of the spontaneous ectopic activity was localized at the location of the maximum CD value. Compared with the last (successful) ablation site (LAS), the mean and standard deviation of localization error of the CDR approach were 13.8 and 1.3 mm, respectively. In comparison, the distance between the LASs and the estimated locations of an equivalent single moving dipole in the heart was 25.5 ± 5.5 mm. The obtained CD distribution of activated sources extending from the catheter ablation site also showed a high consistency with the invasively recorded electroanatomical maps. The noninvasively reconstructed endocardial CD distribution is suitable to predict a region of interest containing or close to arrhythmia source, which may have the potential to guide RF catheter ablation.

Does a Better Perfusion of Deconditioned Muscle Tissue Release Chronic Low Back Pain?

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Paola Valdivieso

2018-03-01

Full Text Available Non-specific chronic low back pain (nsCLBP is a multifactorial condition of unknown etiology and pathogenesis. Physical and genetic factors may influence the predisposition of individuals to CLBP, which in many instances share a musculoskeletal origin. A reduced pain level in low back pain patients that participate in exercise therapy highlights that disuse-related muscle deconditioning may predispose individuals to nsCLBP. In this context, musculoskeletal pain may be the consequence of capillary rarefaction in inactive muscle as this would lower local tissue drainage and washing out of toxic waste. Muscle activity is translated into an angio-adaptative process, which implicates angiogenic-gene expression and individual response differences due to heritable modifications of such genes (gene polymorphisms. The pathophysiologic mechanism underlying nsCLBP is still largely unaddressed. We hypothesize that capillary rarefaction due to a deconditioning of dorsal muscle groups exacerbates nsCLBP by increasing noxious sensation, reducing muscle strength and fatigue resistance by initiating a downward spiral of local deconditioning of back muscles which diminishes their load-bearing capacity. We address the idea that specific factors such as angiotensin-converting enzyme and Tenascin-C might play an important role in altering susceptibility to nsCLBP via their effects on microvascular perfusion and vascular remodeling of skeletal muscle, inflammation, and pain sensation. The genetic profile may help to explain the individual predisposition to nsCLBP, thus identifying subgroups of patients, which could benefit from ad hoc treatment types. Future therapeutic approaches aimed at relieving the pain associated with nsCLBP should be based on the verification of mechanistic processes of activity-induced angio-adaptation and muscle-perfusion.

Two-chambered right ventricle resulting from aberrant muscle bundles: a case report

International Nuclear Information System (INIS)

Lim, T. H.; Ko, K. H.; Im, C. K.; Han, M. C.; Chi, J. G

1979-01-01

The 'Two-chambered right ventricle' is a rare, but unique congenital cardiac anomaly characterized by subdivision of the right ventricle into proximal high pressure chamber and distal low pressure chamber by hypertrophied aberrant muscle bundles. The aberrant muscle bundles traverse the right ventricle from the region of crista supraventricular is to the lower part of the anterior wall of the right ventricle. The ' Two-chambered right ventricle' is usually associated with other congenital cardiac anomalies such as ventricular septal defect, pulmonary valvular stenosis, etc. Therefore this anomaly could be mistakenly diagnosed as Tetralogy of Fallot or isolated interventricular septal defect. The need to separate this entity from other types of infundibular stenosis is emphasized because of the important surgical implications. Authors recently experienced a case of the T wo-chambered right ventricle' resulting from aberrant muscle bundles, that are associated with other cardiac anomalies i.e., pulmonary valvular stenosis, aysplastic tricuspid valve with regurgitation and partial anomalous pulmonary venous return to the right atrium. Here we present the findings of E.K.G., cardiac catheterization, simple chest pa, cine-right ventriculography, and autopsy together with a review of related articles.

Two-chambered right ventricle resulting from aberrant muscle bundles: a case report

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Lim, T. H.; Ko, K. H.; Im, C. K.; Han, M. C.; Chi, J. G [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1979-12-15

The 'Two-chambered right ventricle' is a rare, but unique congenital cardiac anomaly characterized by subdivision of the right ventricle into proximal high pressure chamber and distal low pressure chamber by hypertrophied aberrant muscle bundles. The aberrant muscle bundles traverse the right ventricle from the region of crista supraventricular is to the lower part of the anterior wall of the right ventricle. The ' Two-chambered right ventricle' is usually associated with other congenital cardiac anomalies such as ventricular septal defect, pulmonary valvular stenosis, etc. Therefore this anomaly could be mistakenly diagnosed as Tetralogy of Fallot or isolated interventricular septal defect. The need to separate this entity from other types of infundibular stenosis is emphasized because of the important surgical implications. Authors recently experienced a case of the {sup T}wo-chambered right ventricle' resulting from aberrant muscle bundles, that are associated with other cardiac anomalies i.e., pulmonary valvular stenosis, aysplastic tricuspid valve with regurgitation and partial anomalous pulmonary venous return to the right atrium. Here we present the findings of E.K.G., cardiac catheterization, simple chest pa, cine-right ventriculography, and autopsy together with a review of related articles.

Dynamic changes in the mouse skeletal muscle proteome during denervation-induced atrophy

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Franziska Lang

2017-07-01

Full Text Available Loss of neuronal stimulation enhances protein breakdown and reduces protein synthesis, causing rapid loss of muscle mass. To elucidate the pathophysiological adaptations that occur in atrophying muscles, we used stable isotope labelling and mass spectrometry to quantify protein expression changes accurately during denervation-induced atrophy after sciatic nerve section in the mouse gastrocnemius muscle. Additionally, mice were fed a stable isotope labelling of amino acids in cell culture (SILAC diet containing 13C6-lysine for 4, 7 or 11 days to calculate relative levels of protein synthesis in denervated and control muscles. Ubiquitin remnant peptides (K-ε-GG were profiled by immunoaffinity enrichment to identify potential substrates of the ubiquitin-proteasomal pathway. Of the 4279 skeletal muscle proteins quantified, 850 were differentially expressed significantly within 2 weeks after denervation compared with control muscles. Moreover, pulse labelling identified Lys6 incorporation in 4786 proteins, of which 43 had differential Lys6 incorporation between control and denervated muscle. Enrichment of diglycine remnants identified 2100 endogenous ubiquitination sites and revealed a metabolic and myofibrillar protein diglycine signature, including myosin heavy chains, myomesins and titin, during denervation. Comparative analysis of these proteomic data sets with known atrogenes using a random forest approach identified 92 proteins subject to atrogene-like regulation that have not previously been associated directly with denervation-induced atrophy. Comparison of protein synthesis and proteomic data indicated that upregulation of specific proteins in response to denervation is mainly achieved by protein stabilization. This study provides the first integrated analysis of protein expression, synthesis and ubiquitin signatures during muscular atrophy in a living animal.

Acute Kidney Injury: Definition, Pathophysiology and Clinical Phenotypes.

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Makris, Konstantinos; Spanou, Loukia

2016-05-01

Acute kidney injury (AKI) is a clinical syndrome that complicates the course and worsens the outcome in a significant number of hospitalised patients. Recent advances in clinical and basic research will help with a more accurate definition of this syndrome and in the elucidation of its pathogenesis. With this knowledge we will be able to conduct more accurate epidemiologic studies in an effort to gain a better understanding of the impact of this syndrome. AKI is a syndrome that rarely has a sole and distinct pathophysiology. Recent evidence, in both basic science and clinical research, is beginning to change our view for AKI from a single organ failure syndrome to a syndrome where the kidney plays an active role in the progress of multi-organ dysfunction. Accurate and prompt recognition of AKI and better understanding of the pathophysiologic mechanisms underlying the various clinical phenotypes are of great importance to research for effective therapeutic interventions. In this review we provide the most recent updates in the definition, epidemiology and pathophysiology of AKI.

Pancreatitis in dogs and cats: definitions and pathophysiology.

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Watson, P

2015-01-01

Pancreatitis, or inflammation of the pancreas, is commonly seen in dogs and cats and presents a spectrum of disease severities from acute to chronic and mild to severe. It is usually sterile, but the causes and pathophysiology remain poorly understood. The acute end of the disease spectrum is associated with a high mortality but the potential for complete recovery of organ structure and function if the animal survives. At the other end of the spectrum, chronic pancreatitis in either species can cause refractory pain and reduce quality of life. It may also result in progressive exocrine and endocrine functional impairment. There is confusion in the veterinary literature about definitions of acute and chronic pancreatitis and there are very few studies on the pathophysiology of naturally occurring pancreatitis in dogs and cats. This article reviews histological and clinical definitions and current understanding of the pathophysiology and causes in small animals by comparison with the much more extensive literature in humans, and suggests many areas that need further study in dogs and cats. © 2015 British Small Animal Veterinary Association.

chronic sleep deprevation and ventricular arrhythmias: effect of symphatic nervous system

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Samira Choopani

2016-04-01

Full Text Available Introduction: We assessed the effect of chronic sleep deprivation on incidence of ischemia/reperfusion-induced ventricular arrhythmias (ventricular tachycardia and ventricular fibrillation and the role of the sympathetic nervous system in this respect. Material and methods: Rats were randomly divided into four groups; 1 ischemia/reperfusion group (IR: 30 minutes ischemia followed by 60 minutes reperfusion was induced, 2 control group (CON: rats has been placed in large multiple platforms for 72h prior to ischemia and reperfusion, 3 Chronic sleep deprivation group( SD: 72h sleep deprivation was induced by using small  multiple platform prior to ischemia and reperfusion, 4 Sympathectomy group (SYM: chemical sympathectomy was done 24h before to chronic sleep deprivation and then underwent ischemia and reperfusion. The heart isolated and perfused by langendorff apparatus. After thoracotomy and aorta cannulation, the hearts perfused in the langendorff apparatus using krebs-Henseleit buffer. Hearts were allowed to recovery for 15 min. After recovery period, 15 minutes was considered as baseline prior to 30 minutes ischemia followed by 60 minutes reperfusion.Tow thin stainless stell electrodes fixed on the ventricular apex and right atrium for recording the lead II of electrocardiogram (ECG.Results: There were no significant differences between heart rates between groups, and ventricular tachycardia significantly increased in chronic sleep deprivation group As compared with IR group in ischemia period. Sympathectomy significantly reduced ventricular tachycardia incidence when compared with SD. There is no difference in incidence of ventricular tachycardia between control group and IR group. The incidence of ventricular fibrillation during early reperfusion was significantly augmented (P<0.05 in sleep deprivation group as compared with IR group and Sympathectomy significantly could reverse ventricular fibrillation incidence to IR group level as

Patterns of left ventricular remodeling among patients with essential and secondary hypertension.

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Radulescu, Dan; Stoicescu, Laurentiu; Buzdugan, Elena; Donca, Valer

2013-12-01

High blood pressure causes left ventricular hypertrophy, which is a negative prognostic factor among hypertensive patients. To assess left ventricular geometric remodeling patterns in patients with essential hypertension or with hypertension secondary to parenchymal renal disease. We analyzed data from echocardiograms performed in 250 patients with essential hypertension (150 females) and 100 patients with secondary hypertension (60 females). The interventricular septum and the left ventricular posterior wall thickness were measured in the parasternal long-axis. Left ventricular mass was calculated using the Devereaux formula. The most common remodeling type in females and males with essential hypertension were eccentric and concentric left ventricular hypertrophy (cLVH), respectively. Among patients with secondary arterial hypertension, cLVH was most commonly observed in both genders. The prevalence of left ventricular hypertrophy was higher among patients with secondary hypertension. The left ventricular mass index and the relative left ventricular wall thickness were higher in males and also in the secondary hypertension group. Age, blood pressure values and the duration of hypertension, influenced remodeling patterns. We documented a higher prevalence of LVH among patients with secondary hypertension. The type of ventricular remodeling depends on gender, age, type of hypertension, blood pressure values and the duration of hypertension.

Ventricular Septal Defect (VSD)

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... Call your doctor if your baby or child: Tires easily when eating or playing Is not gaining ... heart procedures. Risk factors Ventricular septal defects may run in families and sometimes may occur with other ...

Epicardial deployment of right ventricular disk during perventricular device closure in a child with apical muscular ventricular septal defect

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Nageswara Rao Koneti

2013-01-01

Full Text Available We report a successful perventricular closure of an apical muscular ventricular septal defect (mVSD by a modified technique. An eight-month-old infant, weighing 6.5 kilograms, presented with refractory heart failure. The transthoracic echocardiogram showed multiple apical mVSDs with the largest one measuring 10 mm. perventricular device closure using a 12 mm Amplatzer mVSD occluder was planned. The left ventricular disk was positioned approximating the interventricular septum; however, the right ventricular (RV disk was deployed on the free wall of the RV due to an absent apical muscular septum and a small cavity at the apex. The RV disk of the device was covered using an autologous pericardium. His heart failure improved during follow-up.

Pathophysiologic insights into motor axonal function in Kennedy disease.

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Vucic, Steve; Kiernan, Matthew C

2007-11-06

Kennedy disease (KD), or spinobulbomuscular atrophy, is a slowly progressive inherited neurodegenerative disorder, marked by prominent fasciculations that typically precede the development of other symptoms. Although the genetic basis of KD relates to triplet (CAG) repeat expansion in the androgen receptor (AR) gene on the X chromosome, the mechanisms underlying the clinical presentation in KD have yet to be established. Consequently, the present study applied axonal excitability techniques to investigate the pathophysiologic mechanisms associated with KD. Peripheral nerve excitability studies were undertaken in 7 patients with KD with compound muscle action potentials (CMAP) recorded from the right abductor pollicis brevis. Strength-duration time constant (KD 0.54 +/- 0.03 msec; controls, 0.41 +/- 0.02 msec, p TEd [90 to 100 msec], 50.75 +/- 1.98%; controls TEd [90 to 100 msec], 45.67 +/- 0.67%, p < 0.01) and hyperpolarizing (KD TEh [90 to 100 msec], 128.5 +/- 6.9%; controls TEh [90 to 100 msec], 120.5 +/- 2.4%) conditioning pulses. Measurements of refractoriness, superexcitability, and late subexcitability changed appropriately for axonal hyperpolarization, perhaps reflecting the effects of increased ectopic activity. In total, the increase in the strength-duration time constant may be the primary event, occurring early in course of the disease, contributing to the development of axonal hyperexcitability in Kennedy disease, and thereby to the generation of fasciculations, a characteristic hallmark of the disease.

Pathophysiology of acute small bowel disease with CT correlation

International Nuclear Information System (INIS)

Sarwani, N.; Tappouni, R.; Tice, J.

2011-01-01

The objective of this article is to review the pathophysiology of acute small bowel diseases, and to correlate the mechanisms of disease with computed tomography (CT) findings. Disease entities will be classified into the following: immune mediated and infectious causes, vascular causes, mechanical causes, trauma, and others. Having an understanding of acute small bowel pathophysiology is a useful teaching tool, and can lead to imaging clues to the most likely diagnosis of acute small bowel disorders.

Right ventricular functional analysis utilizing first pass radionuclide angiography for pre-operative ventricular assist device planning: a multi-modality comparison.

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Avery, Ryan; Day, Kevin; Jokerst, Clinton; Kazui, Toshinobu; Krupinski, Elizabeth; Khalpey, Zain

2017-10-10

Advanced heart failure treated with a left ventricular assist device is associated with a higher risk of right heart failure. Many advanced heart failures patients are treated with an ICD, a relative contraindication to MRI, prior to assist device placement. Given this limitation, left and right ventricular function for patients with an ICD is calculated using radionuclide angiography utilizing planar multigated acquisition (MUGA) and first pass radionuclide angiography (FPRNA), respectively. Given the availability of MRI protocols that can accommodate patients with ICDs, we have correlated the findings of ventricular functional analysis using radionuclide angiography to cardiac MRI, the reference standard for ventricle function calculation, to directly correlate calculated ejection fractions between these modalities, and to also assess agreement between available echocardiographic and hemodynamic parameters of right ventricular function. A retrospective review from January 2012 through May 2014 was performed to identify advanced heart failure patients who underwent both cardiac MRI and radionuclide angiography for ventricular functional analysis. Nine heart failure patients (8 men, 1 woman; mean age of 57.0 years) were identified. The average time between the cardiac MRI and radionuclide angiography exams was 38.9 days (range: 1 - 119 days). All patients undergoing cardiac MRI were scanned using an institutionally approved protocol for ICD with no device-related complications identified. A retrospective chart review of each patient for cardiomyopathy diagnosis, clinical follow-up, and echocardiogram and right heart catheterization performed during evaluation was also performed. The 9 patients demonstrated a mean left ventricular ejection fraction (LVEF) using cardiac MRI of 20.7% (12 - 40%). Mean LVEF using MUGA was 22.6% (12 - 49%). The mean right ventricular ejection fraction (RVEF) utilizing cardiac MRI was 28.3% (16 - 43%), and the mean RVEF calculated by

Estudo da função ventricular na técnica de plicatura da parede livre do ventrículo esquerdo em cães Left ventricular function after plication of the left ventricular free wall in dogs

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James Newton Bizetto Meira de Andrade

2004-06-01

Full Text Available OBJETIVO: Avaliar os efeitos da técnica na função ventricular esquerda em cães hígidos e com cardiomiopatia dilatada induzida pela doxorrubicina. MÉTODO: De 13 cães, oito receberam doxorrubicina até que a fração de encurtamento (FE fosse menor que 20%. Destes, quatro animais e os cinco não induzidos foram submetidos à plicatura da parede livre do ventrículo esquerdo (PPLVE. Os demais cães não foram operados. Foram avaliados débito cardíaco (DC, pressão arterial, exame físico, eletrocardiografia, sistema "Holter" e ecocardiografia, por 180 dias. RESULTADOS: Houve redução do volume ventricular esquerdo. Os cães induzidos melhoraram após a operação e a fração de ejeção (FEj retornou aos valores normais para a espécie. O DC e a FE aumentaram após a operação. Um cão foi a óbito. Nos cães não operados, a FE diminuiu e foram a óbito em torno de 40 dias após a indução; nos cães não induzidos, esta não se alterou. Houve extra-sístoles ventriculares, que se resolveram espontaneamente. CONCLUSÕES: A PPLVE sem circulação extracorpórea reduz o volume ventricular esquerdo e melhora a função cardíaca dos cães com cardiomiopatia dilatada induzida pela doxorrubicina, demonstrando baixa morbidade e mortalidade tardia.OBJECTIVE: We tested a new surgical technique, the plication of the left ventricular free wall, to reduce left ventricular area and volume and improve left ventricular systolic function, without using a cardiopulmonary bypass. METHODS: Dilated cardiomyopathy was induced in eight dogs by the injection of doxorubicin. Plication of the left ventricular free wall was performed in four dogs with induced cardiomyopathy and in five control dogs. Two dogs not submitted to surgery. The other two dogs died during the induction phase. Cardiac output, 2-dimensional and M-mode echocardiography, arterial blood pressure and electrocardiography were recorded over a 180 days period. Ambulatory electrocardiography

Associations of Blood Pressure Dipping Patterns With Left Ventricular Mass and Left Ventricular Hypertrophy in Blacks: The Jackson Heart Study.

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Abdalla, Marwah; Caughey, Melissa C; Tanner, Rikki M; Booth, John N; Diaz, Keith M; Anstey, D Edmund; Sims, Mario; Ravenell, Joseph; Muntner, Paul; Viera, Anthony J; Shimbo, Daichi

2017-04-05

Abnormal diurnal blood pressure (BP), including nondipping patterns, assessed using ambulatory BP monitoring, have been associated with increased cardiovascular risk among white and Asian adults. We examined the associations of BP dipping patterns (dipping, nondipping, and reverse dipping) with cardiovascular target organ damage (left ventricular mass index and left ventricular hypertrophy), among participants from the Jackson Heart Study, an exclusively black population-based cohort. Analyses included 1015 participants who completed ambulatory BP monitoring and had echocardiography data from the baseline visit. Participants were categorized based on the nighttime to daytime systolic BP ratio into 3 patterns: dipping pattern (≤0.90), nondipping pattern (>0.90 to ≤1.00), and reverse dipping pattern (>1.00). The prevalence of dipping, nondipping, and reverse dipping patterns was 33.6%, 48.2%, and 18.2%, respectively. In a fully adjusted model, which included antihypertensive medication use and clinic and daytime systolic BP, the mean differences in left ventricular mass index between reverse dipping pattern versus dipping pattern was 8.3±2.1 g/m 2 ( P pattern versus dipping pattern was -1.0±1.6 g/m 2 ( P =0.536). Compared with participants with a dipping pattern, the prevalence ratio for having left ventricular hypertrophy was 1.65 (95% CI, 1.05-2.58) and 0.96 (95% CI, 0.63-1.97) for those with a reverse dipping pattern and nondipping pattern, respectively. In this population-based study of blacks, a reverse dipping pattern was associated with increased left ventricular mass index and a higher prevalence of left ventricular hypertrophy. Identification of a reverse dipping pattern on ambulatory BP monitoring may help identify black at increased risk for cardiovascular target organ damage. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Stress urinary incontinence in pregnant women: a review of prevalence, pathophysiology, and treatment.

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Sangsawang, Bussara; Sangsawang, Nucharee

2013-06-01

Stress urinary incontinence (SUI) is the most common type of urinary incontinence (UI) in pregnant women and is known to have detrimental effects on the quality of life in approximately 54.3 %. Pregnancy is the main risk factor for the development of SUI. This review provides details of the pathophysiology leading to SUI in pregnant women and SUI prevalence and treatment during pregnancy. We conducted a PubMed search for English-language and human-study articles registered from January 1990 to September 2012. This search was performed for articles dealing with prevalence and treatment of SUI during pregnancy. In the intervention studies, we included studies that used a randomized controlled trial (RCT) design or studies comparing a treatment intervention to no treatment. A total of 534 articles were identified; 174 full-text articles were reviewed, and 28 of them met eligibility criteria and are reported on here. The mean prevalence of SUI during pregnancy was 41 % (18.6-60 %) and increased with gestational age. The increasing pressure of the growing uterus and fetal weight on pelvic-floor muscles (PFM) throughout pregnancy, together with pregnancy-related hormonal changes, may lead to reduced PFM strength as well as their supportive and sphincteric function. These cause mobility of the bladder neck and urethra, leading to urethral sphincter incompetence. Pelvic floor muscle exercise (PFME) is a safe and effective treatment for SUI during pregnancy, without significant adverse effects. Understanding these issues can be useful for health-care professionals when informing and counseling pregnant women to help prevent SUI during pregnancy and the postpartum period.

Right Ventricular Ejection Fraction using ECG-Gated First Pass Cardioangiography

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Moon, Young Hee; Lee, Hae Giu; Lee, Sung Yong; Park, Suk Min; Chung, Soo Kyo; Yim, Jeong Ik; Bahk, Yong Whee; Shinn, Kyung Sub; Kim, Young Gyun; Kwon, Soon Seog [Catholic University College of Medicine, Seoul (Korea, Republic of)

1993-03-15

Radionuclide cardioangiography has been widely applied and has played major roles in moninvasive assessment of cardiac function. Three techniques, first-pass gated first and gated equilibrium methods have commonly been used to evaluate right ventricular ejection fraction which usually abnormal in the patients with cardiopulmonary disease. It has been known that the gated first pass method is most accurate method among the three techniques in assessment of fight ventricular ejection fraction. The radionuclide right ventricular ejection fraction values were determined in 13 normal subjects and in 15 patients with chronic obstructive pulmonary disease by the gated first pass method and compared with those of the first pass method because there has been no published data of fight ejection fraction by the gated first pass method were compared with the defects from the pulmonary function test performed in the patients with chronic obstructive pulmomary disease. The results were as follows; 1) The values of fight ventricular ejection fraction by the gated first pass method were 50.1 +- 6.1% in normal subjects and 38.5 +- 8.5 in the patients with chronic obstructive pulmonary disease. There was statistically significant difference between the right ventricular ejection fraction of each of the two groups (p<0.05) 2) The right ventricular ejection fraction by the gated first pass method was not linearly correlated ith FEV{sub 1}, VC. DLCO. and FVC as well as P{sub a}O2 and P{sub a}CO2 of the patients with chronic obstructive pulmonary disease. We concluded that right ventricular ejection fraction by the gated first pass method using radionuclide cardioangiography may be useful in clinical assessment of the right ventricular function.

Quantitative measurement of ventricular dilatation on CT scan

International Nuclear Information System (INIS)

Okita, Naoshi; Mochizuki, Hiroshi; Takase, Sadao

1985-01-01

Cerebral atrophy might be judged from the ventricular dilatation with some indices, calculated from various ventricular width. But, there is no general agreement on what index is the most reliable. In this paper, we attempted to establish the index, easy to measure and most reliable. Our method is as follow. 1) We carried out the CT scan (EMI 1010) on 89 neurologically intact patients. Scans were parallel to orbito-meatal line (OML), and were 10 mm in thickness. On CT scan films, various width, area of anterior horns and area of bodies of lateral ventricles were measured. Measurement about the anterior horns of lateral ventricles were carried out on image the most clearly showed the foramen of Monro. And measurements about the bodies of lateral ventricles were on image, 20 mm above the image of anterior horn. Correlations of various width and areas were calculated. Then we proposed new indices with high correlations (over 0.9) with ventricular area; Anterior horn CVI (Cerebro-Ventricular Index) and Body CVI. 2) Patients with myotonic dystrophy show cerebral atrophy. We carried out the CT scan (GECT/T 8800) on 17 myotonic dystrophy patients and 30 controls. Between the two groups, age and sex were almost matched. In the two groups, we calculated our new indices as well as various indices which have been reported; Huckman number, Bifrontal CVI, Bicaudal CVI, Anterior horn index, Hirajima's index, and Cella-media index. The data were analyzed statistically. The ventricular dilatation of myotonic dystrophy patients is more definite with Anterior horn CVI, Bicaudal CVI and Body CVI (p<0.01). These indices have higher correlations with the ventricular area (about 0.9). (J.P.N.)

Assessment of ventricular function by radionuclide ventriculography in hyperthyroidism

International Nuclear Information System (INIS)

Dong Weiyu; He Pinyu; Zhuang Weite

1996-01-01

Left ventricular(LV) and right ventricular(RV) function were determined using radionuclide ventriculography in 50 patients with hyperthyroidism. LVEF, LVPFR, SV of the hyperthyroidism group were decreased in comparison with the normal group (P<0.01), whereas CO of the hyperthyroidism patients were higher than that of normal (P<0.01). Except LVPER, the LVEF, SV had significant difference between two groups. Compared to normal group, RVEF, RVPER, RVPFR were also decreased (P<0.01). Besides 30 cases of the hyperthyroidism were examined by impedance cardiogram (ICG) and impedance pulmonary rheogram (IPR), all showed closely correlation with the parameters determined by ventriculography. There was the involvement of right ventricular function insufficiency, especially in ejection phase. When compared with pre-therapy, pos-therapy cases showed significant improvement in EF, PER, PFR of left and right ventricular

Noninvasive assessment of right ventricular wall motion by radionuclide cardioangiography

International Nuclear Information System (INIS)

Nishimura, Tsunehiko; Uehara, Toshiisa; Naito, Hiroaki; Hayashida, Kohei; Kozuka, Takahiro

1981-01-01

Radionuclide cardioangiography is a useful method to evaluate the left ventricular wall motion in various heart diseases. It has been also attempted to assess the right ventricular wall motion simultaneously by radionuclide method. In this study, using the combination of first-pass (RAO 30 0 ) and multi-gate (LAO 40 0 ) method, the site of right vetricle was classified in five. (1 inflow, 2 sinus, 3 outflow, 4 septal, 5 lateral) and the degree of wall motion was classified in four stages (dyskinesis, akinesis, hypokinesis, normal) according to the AHA committee report. These methods were applied clinically to forty-eight patients with various heart diseases. In the cases with right ventricular pressure or volume overload such as COLD, pulmonary infarction, the right ventricle was dilated and the wall motion was reduced in all portions. Especially, in the cases with right ventricular infarction, the right ventricular wall motion was reduced in the infarcted area. The findings of radionuclide method were in good agreement with those of contrast right ventriculography or echocardiography. In conclusion, radionuclide cardioangiography is a useful and noninvasive method to assess not only the left but also the right ventricular wall motion. (author)

Interdependence of right ventricular systolic function and left ventricular filling and its association with outcome for patients with pulmonary hypertension.