Search Results
Results 651 - 700 of 2339
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Kutty Shelby - - 2008
BACKGROUND: This study evaluated regional right ventricular (RV) mechanics before and after pulmonary valve replacement (PVR) by ultrasonic speckle tracking technology using velocity vector imaging (VVI). METHODS: Fifty-eight patients who underwent PVR (May 1999 to August 2007) were included. Two-dimensional Doppler indices included qualitative pulmonary incompetence, RV outflow tract peak ...
Nishio Mayu - - 2008
Clinical characteristics were compared between hypertensive patients with and without heart failure in the absence of reduced ejection fraction (EF) to gain insights into the effects of renal insufficiency on the prevalence of diastolic heart failure. Study subjects consisted of 691 hypertensive patients with an EF>40%. Patients with serum creatinine ...
Toiviainen-Salo Sanna - - 2008
BACKGROUND: Early studies have suggested increased risk of fatal cardiac complications in infants with Shwachman-Diamond syndrome (SDS), an inherited bone marrow failure syndrome. Patients undergoing stem cell transplantation (STC) have appeared susceptible to organ toxicity, including cardiac involvement. PROCEDURE: This study assessed anatomical and functional features of the heart in ...
Zhang Wen W Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford, - - 2008
Patients with muscular dystrophy have abnormal cardiac function and decreased high-energy phosphate metabolism. Here, we have determined whether the 8 month old mdx mouse, an animal model of muscular dystrophy, also has abnormal cardiac function and energetics. In vivo cardiac MRI revealed 33% and 104% larger right ventricular end-diastolic and ...
Westholm Carl - - 2009
BACKGROUND: The use of two-dimensional echocardiography (2D echo) for detection of ischaemia is limited due to high user dependency. Longitudinal motion is sensitive for ischaemia and usable for quantitative measurement of longitudinal myocardial function but time consuming. Velocity tracking (VeT) is a new method that gives an easy three-dimensional understanding ...
Saito M - - 2009
Left ventricular (LV) untwisting velocity has emerged as a novel index of LV diastolic function since it is thought to be related to LV diastolic suction. However, the pathophysiology of LV untwisting behavior has not been fully investigated. The aim of this study was to investigate the determinants of LV ...
Marsan Nina Ajmone - - 2008
Velocity-encoded magnetic resonance imaging (VE-MRI), commonly used to perform flow measurements, can be applied for myocardial velocity analysis, similar to tissue Doppler imaging (TDI). In this study, a comparison between VE-MRI and TDI was performed for the assessment of left ventricular dyssynchrony and left ventricular filling pressures. Ten healthy volunteers ...
Bayram Nihal Akar - - 2008
OBJECTIVES: The effects of continuous positive airway pressure (CPAP) therapy on right ventricular (RV) function in patients with obstructive sleep apnea syndrome (OSAS) has not been previously studied by tissue Doppler imaging (TDI). The aim of this study was to assess RV function using TDI in patients with OSAS before ...
Soylu Ozer - - 2008
BACKGROUND: Conventional noninvasive methods have well-known limitations for the detection of coronary artery disease (CAD) in patients with left bundle branch block (LBBB). However, advancements in Doppler echocardiography permit transthoracic imaging of coronary flow velocities (CFV) and measurement of coronary flow reserve (CFR). Our aim was to evaluate the diagnostic ...
Tashiro Hideki - - 2008
The aim of this study was to evaluate the left ventricular (LV) diastolic function parameter calculated using three-dimensional (3D) echocardiography. METHOD: Using 3D echocardiography and an analysis software program, the left ventricular volume through the cardiac cycle was measured automatically. We therefore calculated 25%, 50%, and 75% of the subtraction ...
Karakurt Cem┼čit - - 2008
Although the anthracyclines have gained widespread use in the treatment of childhood hematological malignancies and solid tumors, cardiotoxicity is the major limiting factor in the use of anthracyclines. The aim of this study was to assess the mitral annular displacement by tissue tracking in pediatric malignancy survivors who had been ...
Pauliks Linda B - - 2008
The noninvasive assessment of cardiac function during mechanical circulatory support is challenging because conventional markers (like ejection fraction) are significantly load-dependent. Yet loading conditions are abnormal and change during support and weaning process. Tissue Doppler and strain rate imaging are echocardiographic techniques that permit quantitation of regional wall motion. Peak ...
Leonardi Benedetta - - 2008
OBJECTIVES: We sought to evaluate whether echocardiographic diastolic function indices correlate with myocardial iron and systolic function in patients with transfusion-dependent thalassemia (TDT) who are at risk for cardiomyopathy. BACKGROUND: In thalassemia syndromes, there is an important clinical need to risk stratify patients for the development of iron-overload cardiomyopathy so ...
Kittipovanonth Maytinee - - 2008
BACKGROUND: In pulmonary hypertension (PHT), right ventricular (RV) function affects treatment strategy and prognosis. Doppler myocardial imaging (DMI) has the potential to detect early RV dysfunction. METHODS: Regional RV function was prospectively assessed in 110 patients without primary structural heart disease, including patients with known PHT (group I; n = ...
Schumacher A - - 2008
Most patients with cardiac disease have diastolic dysfunction which is characterized by impaired diastolic filling and/or abnormal diastolic relaxation. The trans-esophageal echocardiography (TEE) used routinely during open-heart surgical procedures has exceptional resolution that may permit the identification and grading of diastolic dysfunction. The goal of this study was to determine ...
Tsioufis Costas - - 2008
BACKGROUND: Primary aldosteronism (PA) has been experimentally and clinically linked to myocardial and vascular fibrosis, and it has been further associated with left ventricular (LV) structural adaptations. HYPOTHESIS: Functional cardiovascular adaptations in hypertensive patients with PA precede structural alterations in the early stages of the disease. METHODS: We studied 17 ...
Tayyareci Yelda - - 2008
OBJECTIVES: Although right ventricular (RV) systolic dysfunction is an important indicator for the severity of mitral stenosis (MS), its diagnosis is difficult before systemic signs of venous congestion occur. We assessed the association between tissue Doppler (TDI)-derived isovolumic myocardial acceleration (IVA) and the severity of MS. STUDY DESIGN: The study ...
Haraldsson Henrik - - 2008
PURPOSE: To estimate regional myocardial strain rate, with reduced sensitivity to noise and velocities outside the region of interest, and provide a visualization of the spatial variation of the obtained tensor field within the myocardium. MATERIALS AND METHODS: Myocardial velocities were measured using two-dimensional phase contrast velocity mapping. Velocity gradients ...
Dogan Abdullah - - 2009
OBJECTIVE: Atrial and/or appendage stunning (AS) usually occur after successful cardioversion of atrial fibrillation (AF). Several parameters except mitral annular velocity were previously evaluated to determine AS. We investigated whether mitral annular velocity was useful for determining of AS. METHODS: This study consisted of 52 consecutive patients with AF <3 ...
Ishizu Tomoko - - 2008
We evaluated diastolic functional reserve in 108 patients with normal left ventricular ejection fraction (LVEF)> or =50% but abnormal relaxation (ratio of transmitral peak velocity of early and late diastolic flow (E/A)<1) using passive leg lifting. We calculated the pulmonary venous systolic to diastolic flow ratio (S/D) as a marker ...
Wu Weichun - - 2008
BACKGROUND: The authors assessed the capability of quantitative tissue velocity imaging (QTVI) to detect left ventricular (LV) early diastolic dysfunction (LVEDDY) in a canine model. METHODS: Rapid ventricular pacing (RVP) at 240 beats/min was maintained in 14 dogs for 2 weeks. Echocardiography, cardiac catheterization, and endomyocardial biopsies were performed at ...
Ramzy Ihab S - - 2009
AIM: To assess right ventricular (RV) function in patients with inferior myocardial infarction (IMI) and to observe changes following thrombolysis. BACKGROUND: RV dysfunction occurs in 30% of patients with IMI. The extent of such involvement and its potential, recovery has not been determined. METHODS: We studied 30 patients with acute ...
Fayssoil Abdallah - - 2009
Mice allow biologists to study various genes playing a role in cardiac function and pathophysiological situations. Echocardiography is a non-invasive tool for assessing cardiac phenotype. Because of load dependence of conventional parameters (left ventricular shortening fraction, left ventricular ejection fraction and mitral pulsed Doppler), we have to perform Doppler tissular ...
Loureiro J - - 2008
OBJECTIVE: The aims of this study were (i) to evaluate echocardiographic findings and myocardial function including pulsed wave tissue Doppler imaging in dogs with naturally occurring dynamic left ventricular outflow tract obstruction and (ii) to investigate the clinical outcome and response to therapy in these dogs. METHODS: Two cases were ...
Choi Jin-Oh - - 2008
BACKGROUND: In this study, we evaluated the feasibility and clinical usefulness of TS(E-E(') ), the time interval between the onsets of early diastolic mitral inflow velocity (E) and mitral annular velocity (E'), obtained by simultaneously tracing E and E', in terms of evaluating diastolic function. METHODS: By the diastolic functional ...
Ballo Piercarlo - - 2008
BACKGROUND: To explore the prognostic value of left ventricular (LV) longitudinal systolic dysfunction in patients with hypertension. METHODS: In 156 hypertensive subjects, LV longitudinal systolic function was assessed by echocardiographic measurement of M-mode left atrioventricular plane displacement (AVPD) and Tissue Doppler (TD)-derived mitral annulus peak systolic velocity (Sm). Patients were ...
Ng Arnold C T - - 2008
Myocardial velocities have prognostic implications, and transmitral E wave to mitral annular early diastolic tissue velocity ratio (E/Em) is utilized to estimate left ventricular (LV) end-diastolic pressure (EDP). There are no reference values for 2-dimensional (2D) speckle tracking myocardial velocities (S2D, E2D, A2D), and it is unknown if they are ...
Kim Woo-Shik - - 2008
To evaluate intramyocardial coronary flow velocity pattern by transthoracic Doppler echocardiography and its clinical significance in patients with hypertrophic cardiomyopathy (HCM). In 48 patients with HCM who had angiographically normal coronary artery, coronary flow velocity in the left anterior descending coronary artery (LAD) and intramyocardial coronary artery (IMCA) derived from ...
Gulel Okan - - 2008
BACKGROUND: Cardiovascular diseases are responsible for about half of deaths and are the major cause of mortality in hemodialysis patients. The aim of this study is to assess left ventricular (LV) longitudinal myocardial functions by color tissue Doppler imaging (TDI) in patients with chronic renal failure on a regular hemodialysis ...
Almeida Ana G - - 2008
BACKGROUND: Sickle cell disease (SCD) is characterized by obstruction of microvessels leading to ischemia and necrosis. We have aimed to demonstrate whether myocardial contrast echocardiography (MCE) is able to detect myocardial perfusion abnormalities in SCD patients and to assess their relationship with left ventricle (LV) perfusion and systolic function. METHODS: ...
Friedberg Mark K - - 2008
BACKGROUND: We investigated diastolic mechanical dyssynchrony and its relation to clinical status in pediatric dilated cardiomyopathy (DCM). METHODS AND RESULTS: We calculated a diastolic and systolic dyssynchrony index (standard deviation of time to peak tissue early diastolic/systolic velocity in 12 left ventricular segments) in 33 children with DCM and 46 ...
Koffas H - - 2008
OBJECTIVES: To determine whether decreased diastolic and systolic myocardial velocity gradient between the endocardium and the epicardium exist in the left ventricle of cats with hypertrophic cardiomyopathy. METHODS: Myocardial velocity gradient and mean myocardial velocities were measured by colour M-mode tissue Doppler imaging in the left ventricular free wall of ...
Hubbert Laila - - 2008
The aim of this study was to investigate flow characteristics and myocardial function after implantation of an axial pump left ventricular assist device while varying afterload and during progressive myocardial depression. Ten calves were included, seven of which fulfilled the protocol. Invasive hemodynamic monitoring and echocardiography with color-coded systolic tissue ...
Amoozgar Hamid - - 2008
Doppler tissue imaging (DTI) has been proposed as a tool for evaluation of diastolic function. Controversy exists regarding whether DTI measurements are influenced by preload. To determine the influence of preload reduction on DTI, we studied 17 patients (mean age 17 +/- 1.82 years) with end-stage renal disease and without ...
Esmaeilzadeh Maryam - - 2009
AIMS: Enhanced external counter pulsation (EECP) is a non-invasive and non-pharmacological therapy for patients with symptomatic coronary artery disease (CAD). There are, however, insufficient data to support the effectiveness of EECP in improving the myocardial mechanical properties of patients with refractory stable angina. We aimed to assess the effects of ...
Hirsch Alexander - - 2008
OBJECTIVES: We studied the relation between presence and severity of microvascular obstruction (MO), measured by cardiovascular magnetic resonance (CMR) and intracoronary Doppler flow measurements, for assessment of myocardial reperfusion in patients with acute anterior myocardial infarction (MI) treated by primary percutaneous coronary intervention (PCI). BACKGROUND: Cardiovascular magnetic resonance has been ...
Bahtiyar Mert Ozan - - 2008
Intrauterine growth restriction (IUGR), which complicates approximately 3% to 10% of all pregnancies leads to preferential hemodynamic changes in affected fetuses. Advanced ultrasound modalities allow reliable and reproducible assessment of the intrauterine fetal cardiac function. Among other methods, combined cardiac output, individual ventricular ejection forces, E/A ratio, and Tei index ...
Nelson O Lynne - - 2008
The hibernation phenomenon captures biological as well as clinical interests to understand how organs adapt. Here we studied how hibernating grizzly bears (Ursus arctos horribilis) tolerate extremely low heart rates without developing cardiac chamber dilation. We evaluated cardiac filling function in unanesthetized grizzly bears by echocardiography during the active and ...
van der Meer Rutger W - - 2008
AIMS: In animal models of obesity and diabetes mellitus, myocardial TG accumulation is associated with decreased myocardial function. In the physiologically ageing heart, myocardial triglyceride (TG) accumulation may also occur due to reduced myocardial fatty acid oxidation. The role of myocardial TG in the ageing human heart is unknown. Therefore, ...
Miyazaki Chinami - - 2008
BACKGROUND: Several echocardiographic dyssynchrony indexes have been proposed to identify responders to cardiac resynchronization therapy using tissue velocity and strain. The present study aimed to compare tissue velocity-derived and strain-derived dyssynchrony indexes in patients with or without systolic dysfunction and left bundle-branch block. METHODS AND RESULTS: Tissue Doppler imaging was ...
King G J - - 2008
BACKGROUND: In elite athletes left ventricular (LV) morphological changes are predicted to alter passive pressure/volume characteristics by reducing myocardial stiffness and increasing compliance. OBJECTIVE: To investigate the utility of a new Doppler tissue index based on the pressure volume relation ((E/Ea)/LVEDD), which provides a measure of myocardial stiffness, and to ...
Tousignant Claude P - - 2008
OBJECTIVES: Tricuspid annular isovolumic acceleration is a load-independent measure of contractility, but its relationship to heart rate is unknown in humans. The authors investigated the effect of heart rate on measurements of isovolumic acceleration and systolic wave velocities in postoperative cardiac surgical patients with atrial fibrillation. DESIGN: This was a ...
Simpson Kerry E - - 2008
The identification and assessment of myocardial failure in canine idiopathic dilated cardiomyopathy (DCM) is achieved using a variety of two-dimensional and Doppler echocardiographic techniques. More recently, the availability of tissue Doppler imaging (TDI) has raised the potential for development of new ways of more accurately identifying a disease phenotype. Nevertheless, ...
Duan Yuqing - - 2008
The aim was to compare the right ventricular (RV) Tei index obtained by the tissue Doppler imaging (TDI) method with that obtained by the pulsed Doppler method in 29 fetuses aged 24-39 weeks (29.9 +/- 4.0 weeks). From pulsed Doppler recordings, the tricuspid closing-to-opening time (a) and RV ejection time ...
Fontes-Sousa Ana Patrícia - - 2009
Limited data are available on the use of more recent echocardiographic parameters in the rabbit. Echocardiographic examination, including conventional echocardiography and tissue Doppler imaging (TDI), was performed on 26 male New Zealand white rabbits under ketamine-midazolam sedation. Particular emphasis was placed on the more recent systolic and diastolic parameters, such ...
Arnold Raoul - - 2008
BACKGROUND: Ventricular dysfunction represents one of the major problems in the long-term follow-up of patients after atrial repair for dextrotransposition of the great arteries. We aimed to study the role of tissue Doppler derived isovolumic acceleration (IVA) to detect early myocardial dysfunction in these patients. METHODS: Twenty-four patients with dextrotransposition ...
Rajagopalan Navin - - 2008
OBJECTIVES: The objective of this study was to correlate tissue Doppler imaging of the right ventricle (RV) with pulmonary hemodynamics in patients referred for right heart catheterization. METHODS: Seventy subjects (mean age 54 +/- 13; 35 males) prospectively underwent tissue Doppler imaging of the RV and right heart catheterization within ...
Ganame Javier - - 2008
AIMS: Hypertrophic cardiomyopathy (HCM) is a disease with a heterogeneous clinical and morphological presentation. It can be secondary to mutations in genes encoding for sarcomeric and non-sarcomeric proteins. The pattern of ventricular hypertrophy can vary from isolated basal septal to concentric hypertrophy. We investigated if there are differences in regional ...
Zywica K - - 2008
AIMS: In patients without hypertrophic obstructive cardiomyopathy (HOCM), dynamic left ventricular outflow tract obstruction (DLVOTO) can cause ischaemia. Little is known about incidence and predictors of DLVOTO in patients without HOCM. METHODS AND RESULTS: In 300 patients referred for exercise echocardiography, assessment of DLVOTO at rest and with Valsalva and ...
Dobbe J G G - - 2008
This study describes a new method for analyzing microcirculatory videos. It introduces algorithms for quantitative assessment of vessel length, diameter, the functional microcirculatory density distribution and red blood-cell (RBC) velocity in individual vessels as well as its distribution. The technique was validated and compared to commercial software. The method was ...
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