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Hori Yasutomo - - 2007
Tissue Doppler imaging (TDI) is effective in assessing right ventricular (RV) function, but the relationship between invasive measurements and RV-TDI remains unclear. We investigated the RV systolic function by using the TDI-derived systolic myocardial (Sa) velocity and myocardial performance index (MPI). Beagles (n = 7) were anesthetized in the right ...
Carlsson Marcus - - 2007
The total heart volume variation (THVV) during systole has been proposed to be caused by radial function of the ventricles, but definitive data for both ventricles have not been presented. Furthermore, the right ventricle (RV) has been suggested to have a greater longitudinal pumping component than the left ventricle (LV). ...
Saricam Ersin - - 2007
AIM: The right ventricular (RV) systolic function is an important determinant of clinical symptoms and exercise capacity in patients with mitral stenosis. No sufficient data are available concerning the effect of RV diastolic function on symptoms of patients with mitral stenosis. In the presence of normal RV systolic function, RV ...
van Wolferen Serge A - - 2007
AIMS: This study investigated the relationship between right ventricular (RV) structure and function and survival in idiopathic pulmonary arterial hypertension (IPAH). METHODS AND RESULTS: In 64 patients, cardiac magnetic resonance, right heart catheterization, and the six-minute walk test (6MWT) were performed at baseline and after 1-year follow-up. RV structure and ...
Umar Soban - - 2007
Pulmonary hypertension induces right ventricular (RV) overload, which is transmitted to cardiomyocytes via integrins that activate intracellular messengers, including focal adhesion kinase (FAK) and neuronal nitric oxide synthase (NOS1). We investigated whether RV hypertrophy (RVH) and RV failure (RVF) were associated with activation of FAK, NOS1, and matrix metalloproteinases (MMPs). ...
Clements Ian P - - 2007
BACKGROUND: Successful thromboendarterectomy for chronic thromboembolic pulmonary hypertension promptly improves right ventricular (RV) function by decreasing RV volume and increasing ejection fraction (EF). Single photon emission computed tomography (SPECT) equilibrium radionuclide angiocardiography (ERNA) has been validated as a measure of RV and left ventricular (LV) volume and EF. METHODS AND ...
Frydrychowicz A - - 2007
Precise and noninvasive characterization of the development of the cardiac phenotype in murine models of heart failure has been widely demanded in modern cardiovascular research. High-resolution cardiovascular magnetic resonance (CMR) has been proven to be a powerful tool for the accurate and reproducible assessment of LV and RV parameters in ...
Djelmami-Hani M - - 2007
We compared three methods: arteriovenous anastomosis, doxorubicin administration, and combination of anastomosis and doxorubicin, with the intention of designing a simple, stable model of chronic heart failure. Twelve dogs were divided into three groups of four. One group received carotid-jugular anastomosis (Ana series), another group received anastomosis and doxorubicin injection ...
Akgül Ferit - - 2007
The purpose of this investigation was to assess the effects of acute hypoxia on left (LV) and right ventricular (RV) contractility in clinically stable chronic obstructive pulmonary disease (COPD) patients. Eleven male patients (mean age 52.4 +/- 12.6 years) who were diagnosed to have COPD were included into the study. ...
Law Yuk - - 2006
Clinical recognition of allograft coronary artery disease (ACAD) is challenging. We examined whether right heart hemodynamics can aid its diagnosis in pediatric recipients. We retrospective analyzed hemodynamic data of recipients with ACAD versus age and date-of-transplant matched controls. From 1982-2001, 18 cases fulfilled study entry criteria. Median age at transplant ...
Laviolle Bruno - - 2006
BACKGROUND: In congestive heart failure, enalapril (E), metoprolol (M), and spironolactone (S) improve survival. Their direct effects on cardiac remodeling, when administered in combination, remain to be assessed. METHODS AND RESULTS: One hundred and five cardiomyopathic hamsters were divided into 5 groups (control, E, E-M, E-S, E-M-S) and treated from ...
Uehara Masae - - 2007
A 60 year-old male presented with abnormal systolic heart murmur. Transthoracic echocardiogram revealed right ventricular (RV) hypertrophy and mosaic jet in the RV outflow tract. RV catheterization revealed significantly pressure gradient between the RV and the pulmonary artery. Enhance ECG-gated multislice CT was performed and an axial source image in ...
Maceira Alicia M - - 2006
AIMS: Recent advances in cardiovascular magnetic resonance (CMR) include improved image quality with steady-state free precession (SSFP) sequences and advanced post-processing of high temporal resolution ventricular function. We used these techniques to establish the reference values for right ventricular (RV) volumes and function. METHODS AND RESULTS: We studied 120 healthy ...
Ghanayem Nancy S - - 2006
BACKGROUND: A comprehensive assessment of 48 hour postoperative hemodynamics in neonates randomized to the right ventricle-to-pulmonary artery (RV-PA) conduit or modified Blalock-Taussig (BT) shunt for stage 1 palliation of hypoplastic left heart syndrome was performed to determine the potential benefits of the modified technique. METHODS: Randomization to either RV-PA conduit ...
Kerbaul François - - 2006
OBJECTIVE: A transient increase in pulmonary arterial (PA) pressure can persistently depress right ventricular (RV) contractility. We investigated the effects of dobutamine and levosimendan on RV-PA coupling in this model of RV failure. DESIGN: Prospective, controlled, randomized animal study. SETTING: University research laboratory. SUBJECTS: Fifteen anesthetized dogs. INTERVENTIONS: Transient (90-min) ...
Joung Boyoung - - 2006
This study was performed to assess the influence of the cryoinjury on the dynamics of wavefronts and to determine whether they can convert ventricular fibrillation (VF) to ventricular tachycardia (VT) in fibrillating right ventricular (RV) of swines using an optical mapping system. A cryoinjury with a diameter of 12 mm ...
Liu Li - - 2006
Pulmonary hypertension (PH) is a life-threatening disorder with high mortality rates and limited treatment options. Gene therapy is an alternative treatment strategy, yet viral vectors have inherent disadvantages including immune activation. The Sleeping Beauty (SB) transposon is a nonviral method of gene delivery that overcomes some of these drawbacks. A ...
Morita Hiroshi - - 2007
BACKGROUND: Fever promotes ventricular arrhythmias in Brugada syndrome (BrS). Hypothermia can induce BrS electrocardiogram (ECG) and arrhythmia. However, the mechanisms are unclear. OBJECTIVE: We evaluated the hypothesis that pathological temperatures promoted arrhythmogenesis by modulating the spatial heterogeneity and functional dynamics of right ventricular electrophysiological activity. METHODS: We mapped action potentials ...
Parissis John T - - 2006
Right ventricular (RV) dysfunction frequently complicates advanced left ventricular heart failure and contributes to an unfavorable prognosis. Levosimendan is a novel inodilator that beneficially affects hemodynamics and left ventricular systolic and diastolic function in patients with advanced heart failure. However, its effects on RV function have not yet been properly ...
Saxena Neil - - 2006
Assessment of right ventricular (RV) systolic function can be somewhat difficult, particularly in pulmonary hypertension (PH). RV fractional area change (FAC) and tricuspid valve annular motion (TAPSE) although useful in the assessment of RV performance, their use can be sometimes limited and tedious. Thus, a quicker but yet reliable alternative ...
Her Charles - - 2006
BACKGROUND: The increased pulmonary blood volume associated with the increased total blood volume in morbidly obese patients increases pulmonary artery pressure and pulmonary vascular resistance, resulting in increased right ventricular (RV) afterload. Thus, the morbidly obese may develop RV dysfunction owing to the increased RV afterload. We examined this possibility ...
Kaye Gerry - - 2006
AIMS: To determine the feasibility of discriminating haemodynamically stable from unstable arrhythmias using right ventricular (RV) unipolar intracardiac impedance (Z). METHODS AND RESULTS: A quadrapolar temporary pacing electrode was positioned at the RV apex and unipolar impedance was measured between the tip electrode and a surface patch electrode. Changes in ...
Sathaye Alok - - 2006
Previous studies have demonstrated the relationship between the functional electrophysiological properties of cultured neonatal rat ventricular myocytes (NRVMs) and the ability of the substrate to induce and sustain arrhythmia. The goal of this study was to examine the effects of chronic pacing at a constant rate akin to that in ...
Lamberts Regis R - - 2007
Right ventricular (RV) pressure overload causes right ventricular hypertrophy in several types of pulmonary and congenital heart diseases. The associated cardiac dysfunction has generally been attributed to alterations in RV function. However, due to global neurohormonal adaptations and mechanical ventricular interaction left ventricular (LV) function could be affected as well.Therefore,LV ...
Mahapatra Srijoy - - 2006
OBJECTIVES: We sought to determine if a novel measurement of pulmonary vascular (PV) capacitance (PVCAP) by Doppler echocardiography predicts all-cause mortality in patients with primary pulmonary arterial (PA) hypertension (PPAH). BACKGROUND: The prognosis of patients with PPAH is variable and has been difficult to predict using clinical or hemodynamic parameters. ...
Sun Yichun - - 2006
Wave speed (c) must be known to separate forward- and backward-going waves during wave-intensity analysis, which measures the energy transported by the waves in the circulation. c is related to elastance; the present study was performed to measure right ventricular (RV) c during the cardiac cycle and to compare c ...
Cioffi Giovanni - - 2007
BACKGROUND AND AIM: Pulmonary hypertension (PH) determines various adaptive changes in right ventricular (RV) geometry which may progressively lead to hypertrophy, mechanical dysfunction and dilatation with pump failure. Right atrium (RA) is theoretically involved in this physiopathological process, but its role has never been investigated. We hypothesized that RA increases ...
Wu Tsu-Juey - - 2006
INTRODUCTION: The dominant frequency (DF) during ventricular fibrillation (VF) in Langendorff-perfused guinea pig hearts is higher in left ventricle (LV) than in right ventricle (RV). However, the onset of VF invariably leads to global ischemia. Whether or not a high DF source exists in LV during global ischemia is unknown. ...
Pirat Bahar - - 2006
This study sought to demonstrate that a novel speckle-tracking method can be used to assess right ventricular (RV) global and regional systolic function. Fifty-eight patients with pulmonary arterial hypertension (11 men; mean age 53 +/- 14 years) and 19 age-matched controls were studied. Echocardiographic images in apical planes were analyzed ...
Vonk M C - - 2007
OBJECTIVE: To assess the accuracy of echocardiography for predicting pulmonary arterial hypertension (PAH) in a cohort of patients with systemic sclerosis and other connective tissue diseases, and to evaluate whether addition of the right ventricular (RV) Tei-index contributes to the non-invasive diagnosis of PAH in this patient group. PATIENTS AND ...
Sun Yichun - - 2006
Diastolic suction (DS) can be defined as that property of the ventricle by means of which it tends to refill itself during early diastole, independent of any force from the atrium. Although thought to be significant in the left ventricle (LV), DS in the right ventricle (RV) has received little ...
Qureshi Naveen - - 2006
OBJECTIVE: To assess the effects of sickle cell anemia (SCA) on the right ventricle (RV). STUDY DESIGN: Echocardiograms of 32 children with SCA were compared with age-matched healthy controls. RV measurements included diastolic area index, fractional area change, free-wall mass index, ejection time corrected for heart rate (ET(c)), and tricuspid ...
Hsiao Shih-Hung - - 2006
OBJECTIVES: Peak systolic mitral annular velocities correlate with left ventricular ejection fraction (EF) regardless of mitral regurgitation severity. Peak systolic tricuspid annular velocity (RV-Sm) and tricuspid annular plane systolic excursion (TAPSE) are used to assess right ventricular (RV) EF (RVEF). We investigated whether tricuspid regurgitation (TR) affects the relationship among ...
Kosar Feridun - - 2006
Clinical hypothyroidism (HT) is often associated with cardiovascular disorders, such as endothelial and myocardial dysfunction. Previous studies have explored left ventricular (LV) function using pulsed-wave tissue Doppler echocardiography (TDE) in HT. However, no study has utilized this technique in the assessment of right ventricular (RV) function in HT. Accordingly, we ...
Watts John A - - 2006
Acute right ventricular (RV) failure following pulmonary embolism (PE) is a strong predictor of poor clinical outcome. Present studies test for an association between RV failure from experimental PE, inflammation, and upregulated chemokine expression. Additional experiments test if neutrophil influx contributes to RV dysfunction. PE was induced in male rats ...
Gibbons Kroeker Carol A - - 2006
During pulmonary artery constriction (PAC), an experimental model of acute right ventricular (RV) pressure overload, the interventricular septum flattens and inverts. Finite element (FE) analysis has shown that the septum is subject to axial compression and bending when so deformed. This study examines the effects of acute PAC on the ...
Quinn T Alexander - - 2006
Temporary sequential biventricular pacing (BiVP) is a promising treatment for postoperative cardiac dysfunction, but the mechanism for improvement in right ventricular (RV) dysfunction is not understood. In the present study, cardiac output (CO) was optimized by sequential BiVP in six anesthetized, open-chest pigs during control and acute RV pressure overload ...
Yamagishi Shigeki - - 2006
PURPOSE: This prospective study was conducted to assess the influences of hemodynamics and right ventricular (RV) performance after lobectomy by video-assisted thoracic surgery (VATS) and that by muscle-sparing thoracotomy (MST) using a continuous cardiac output (CCO) monitoring system. SUBJECTS AND METHODS: Between October 2002 and April 2004, 16 patients (VATS, ...
Do─čan Halil - - 2006
The objective of our study was to validate using MDCT for the assessment of right ventricular (RV) function. MDCT with retrospective ECG gating was performed in 15 patients being evaluated for suspected cardiovascular disease. Echocardiography was performed for comparison. The MDCT images were reconstructed at 20 phase points over the ...
Kim Hyung-Kwan - - 2006
We performed a prospective study of patients with chronic right ventricular (RV) dilation to determine the factors associated with the degree of functional tricuspid regurgitation (FTR). We prospectively enrolled 64 patients with chronic RV dilation and measured right atrial (RA) area, RV area and its fractional area change (RVFAC), tricuspid ...
Hessel Marleen H M - - 2006
We characterized hemodynamics and systolic and diastolic right ventricular (RV) function in relation to structural changes in the rat model of monocrotaline (MCT)-induced pulmonary hypertension. Rats were treated with MCT at 30 mg/kg body wt (MCT30, n = 15) and 80 mg/kg body wt (MCT80, n = 16) to induce ...
Faber Matthijs J - - 2006
In many patients with congenital heart disease, the right ventricle (RV) is subjected to abnormal loading conditions. To better understand the state of compensated RV hypertrophy, which could eventually progress to decompensation, we studied the effects of RV pressure overload in rats. In the present study, we report the biventricular ...
McLean Anthony S - - 2007
AIMS: Detecting the presence of pulmonary hypertension (PH) is important especially with unexplained dyspnoea and suspected thromboembolism. Although PH can be detected invasively by right ventricular (RV) catheterisation, accurate non-invasive assessment by echocardiography has many advantages. This however relies on the presence of tricuspid regurgitation (TR). We examined if the ...
Otsuka Masaya - - 2006
Noonan syndrome presents with dysmorphic facial features, short stature, and cardiac abnormalities (most commonly pulmonic stenosis and hypertrophic cardiomyopathy). This report describes a rare case accompanied by a secundum atrial septal defect (ASD) and a ventricular septal aneurysm causing right ventricular (RV) pressure gradient. A 29-year-old mentally retarded man was ...
Kjaergaard Jesper - - 2006
BACKGROUND: Several quantitative echocardiographic measures of global and regional right ventricular (RV) function have been proposed, but knowledge of the impact of increases in preload and afterload is limited. METHODS: Seventeen healthy participants were exposed to increased preload by rapid infusion of 30 mL/kg of saline over 15 minutes, and ...
Fossa Anthony A - - 2007
INTRODUCTION: The arrhythmogenic risk of fluoxetine, citalopram, and venlafaxine were evaluated through preclinical assays measuring hERG, blood pressure and electrical alternans over their respective clinical unbound concentration ranges. METHODS: Anesthetized guinea pigs were instrumented with jugular and carotid cannulae for drug infusion and blood pressure monitoring respectively; a thoracotomy was ...
Tedrow Usha B - - 2006
The degree to which increased right-sided heart pressures influence outcome in cardiac resynchronization therapy (CRT) is unclear. High right ventricular (RV) pressures may contribute to septal malpositioning, thus hindering effective resynchronization. We hypothesized that patients with high RV systolic pressures before CRT implantation would have poorer outcome. We evaluated echocardiograms, ...
Gencer Mehmet - - 2006
Diffuse systemic-pulmonary anastomoses and chronic hypoxemia may result in increase in ventricular work in bronchiectasis. We aimed to assess right ventricular (RV) and left ventricular (LV) functions in patients with bronchiectasis by using tissue Doppler-derived myocardial performance index (MPI), which is a novel and more sensitive parameter than conventional ventricular ...
Larsen Karl-Otto - - 2006
Chronic obstructive pulmonary disease (COPD) may lead to pulmonary hypertension (PH) and reduced function of the right ventricle (RV). However, COPD patients may also develop left ventricular (LV) diastolic dysfunction. We hypothesized that alveolar hypoxia induces LV diastolic dysfunction and changes in proteins governing Ca(2+) removal from cytosol during diastole. ...
Clark T J - - 2006
We present normative data on cardiac volume, geometry and shape derived using three-dimensional echocardiography (3-DE). Three-dimensional reconstructions were created using the piecewise smooth surface subdivision (PSSS) reconstruction technique of the left and right ventricular (LV and RV) endocardium and the mitral and tricuspid annuli (MA and TA) of 67 normal ...
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