Search Results
Results 351 - 400 of 2734
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Johnson Lauren - - 2007
The goal of the present study was to assess the effects of left ventricular (LV) pacing sites (apex vs. free wall) on radial synchrony and global LV performance in a canine model of contraction dyssynchrony. Ultrasound tissue Doppler imaging and hemodynamic (LV pressure-volume) data were collected in seven anesthetized, opened-chest ...
Marsan Nina Ajmone - - 2008
PURPOSE: To compare left ventricular (LV) dyssynchrony assessment by phase analysis from gated myocardial perfusion SPECT (GMPS) with LV dyssynchrony assessment by tri-plane tissue Doppler imaging (TDI). Baseline LV dyssynchrony assessed with standard deviation (SD) of time-to-peak systolic velocity of 12 LV segments (Ts-SD) with TDI has proven to be ...
Hung Judy - - 2007
BACKGROUND: Recurrent ischemic mitral regurgitation (IMR) is frequent despite initial reduction by annuloplasty because continued LV remodeling increases tethering to the infarcted papillary muscle (PM). We have previously shown that PM repositioning by an external patch device can acutely reduce IMR. In this study, we tested the hypothesis that IMR ...
Fox Ervin R - - 2007
BACKGROUND: There are limited data on the prevalence and the clinical and echocardiographic correlates of pure valvular regurgitation in African Americans despite the higher rates of cardiovascular disease in this group. PURPOSE: The Jackson, Mississippi, site of the Atherosclerosis Risk in Communities study provides a unique opportunity to study mitral ...
Mitoff Peter R - - 2007
BACKGROUND: Women with systolic heart failure (HF) demonstrate better survival than men. Whether sex differences occur in hemodynamics or measures of left ventricular (LV) function is not well understood. METHODS: We retrospectively analyzed a cohort who underwent evaluation by right heart catheterization +/- micromanometer-tipped catheterization of the LV. Two groups, ...
Nakao Shinji - - 2007
BACKGROUND: Although Doppler left ventricular (LV) filling abnormalities have been extensively analyzed in patients with systolic heart failure (SHF), they have not yet been well characterized in patients with acute to chronic diastolic heart failure (DHF) in the light of plasma brain natriuretic peptide (BNP) levels. METHODS AND RESULTS: In ...
Boussuges Alain - - 2007
The present study was designed to assess the cardiac changes induced by cold water immersion compared with dry conditions during a prolonged hyperbaric and hyperoxic exposure (ambient pressure between 1.6 and 3 ATA and PiO(2) between 1.2 and 2.8 ATA). Ten healthy volunteers were studied during a 6 h compression ...
Nishijima Yoshinori - - 2007
While cardiac resynchronization therapy (CRT) has been shown to reduce morbidity and mortality in heart failure (HF) patients, the fundamental mechanisms for the efficacy of CRT are poorly understood. The lack of understanding of these basic mechanisms represents a significant barrier to our understanding of the pathogenesis of HF and ...
Alter P - - 2008
In experimental animals, cardiac work is derived from pressure-volume area and analyzed further using stress-length relations. Lack of methods for determining accurately myocardial mass has until now prevented the use of stress-length relations in patients. We hypothesized, therefore, that not only pressure-volume loops but also stress-length diagrams can be derived ...
Lionetti Vincenzo - - 2007
Increased glucose utilization and regional differences in contractile function are well-known alterations of the failing heart and play an important pathophysiological role. We tested whether, similar to functional derangement, changes in glucose uptake develop following a regional pattern. Heart failure was induced in 13 chronically instrumented minipigs by pacing the ...
Ceyhan Ceyhun - - 2008
The utility of N-Terminal pro Brain Natriuretic Peptide (NT-proBNP) and Brain Natriuretic Peptide (BNP) for detecting left ventricular (LV) diastolic dysfunction in hypertensive patients without heart failure symptoms is unclear. In this study, we investigated the relation between NT-proBNP plasma levels and LV diastolic dysfunction in hypertensive patients without systolic ...
Tsai Chia-Ti - - 2008
BACKGROUND: To evaluate the left atrial (LA) volume, and LA systolic (contractile) and diastolic (expansion) functions in different stages of hypertension with or without atrial fibrillation (AF), as well as the effects of good blood pressure control. METHODS: A prospective observational study. Individuals including 22 normotensive controls, 23 patients with ...
Mansouri Vafa - - 2007
BACKGROUND: With left ventricular (LV) dysfunction, it is not clear how alterations in external constraint influence the index of myocardial performance (IMP). We have previously demonstrated that pericardial constraint is a factor in the production of the restrictive filling pattern. We hypothesized that altering pericardial constraint by changing intracardiac volume ...
Ballo Piercarlo - - 2007
OBJECTIVE: Previous studies evaluated the effect of obesity on left ventricular (LV) mass and systolic function in healthy subjects and in patients with coexistent chronic LV pressure overload due to hypertension, but no data exist regarding subjects with underlying volume overload. This study assessed the impact of overweight-obesity on LV ...
Fei Hongwen - - 2007
The volume-time curve change in patients with normal left ventricular (LV) diastolic function and diastolic dysfunction was evaluated by real-time three-dimensional echocardiography (RT3DE). LV diastolic dysfunction was defined by E'<A' in pulse-wave tissue Doppler for inter-ventricular septal (IVS) of mitral annulus. In 24 patients with LV diastolic dysfunction, including 12 ...
Kasner Mario - - 2007
BACKGROUND: Various conventional and tissue Doppler echocardiographic indexes were compared with pressure-volume loop analysis to assess their accuracy in detecting left ventricular (LV) diastolic dysfunction in patients with heart failure with normal ejection fraction (HFNEF). METHODS AND RESULTS: Diastolic dysfunction was confirmed by pressure-volume loop analysis obtained by conductance catheter ...
Neuman Yoram - - 2008
BACKGROUND: Pulmonary arterial hypertension is a well-established sequel of LV systolic dysfunction; however its association with diastolic dysfunction in subjects with normal LV systolic function has not been thoroughly studied. The aim of this study was to evaluate the correlation between diastolic dysfunction and pulmonary arterial hypertension in patients with ...
Duda Monika K - - 2007
Epidemiological studies suggest that consumption of omega-3 polyunsaturated fatty acids (omega-3 PUFA) decreases the risk of heart failure. We assessed the effects of dietary supplementation with omega-3 PUFA from fish oil on the response of the left ventricle (LV) to arterial pressure overload. Male Wistar rats were fed a standard ...
Shah Sanjiv J - - 2008
BACKGROUND: The third heart sound (S(3)) is thought to be caused by the abrupt deceleration of left ventricular (LV) inflow during early diastole, increased LV filling pressures, and decreased LV compliance. We sought to determine whether the ratio of early mitral inflow velocity to diastolic velocity of the mitral annulus ...
Malmqvist K - - 2007
Hypertensive left ventricular (LV) hypertrophy is associated with a substantial risk for malignant arrhythmias and sudden death. According to recent results, antihypertensive therapy with the angiotensin II type 1 receptor blocker irbesartan reverses both structural and electrical remodelling. However, the relation between the LV geometric pattern (concentric vs eccentric) and ...
Dokainish Hisham - - 2007
Noninvasive left ventricular (LV) pressure estimation in obese patients has not been well described. Simultaneous B-type natriuretic peptide (BNP) and echocardiographic Doppler examinations were performed in patients with dyspnea undergoing cardiac catheterization. Patients were divided into body mass index (BMI) >35 (markedly obese), 31 to 35 (obese), and < or ...
Lalande Sophie - - 2007
The existence of resistance training-induced left ventricular (LV) concentric hypertrophy is equivocal. Although some have described significant LV hypertrophy, others have suggested that training-induced LV hypertrophy is proportional to increased fat free mass (FFM) and thus a normal physiologic response to training. Method limitations, steroid use, and type of training ...
Frielingsdorf Jürgen - - 2008
BACKGROUND: The short-term effect of acute biventricular pacing on cardiac function in patients with chronic heart failure undergoing heart surgery is widely unknown. The present study was designed to determine whether mitral annular tissue Doppler imaging (TDI) is useful to predict acute changes in global systolic function determined by the ...
Shapiro Brian P - - 2007
Aging and hypertension lead to arterial remodeling and tandem increases in arterial (Ea) and ventricular (LV) systolic stiffness (ventricular-arterial [VA] coupling). Age and hypertension also predispose to heart failure with normal ejection fraction (HFnlEF), where symptoms during hypertensive urgencies or exercise are common. We hypothesized that: (1) chronic VA coupling ...
Vernooy Kevin - - 2007
AIMS: We investigated to what extent biventricular pacing (BVP) can normalize LV function and remodeling, induced by isolated left bundle branch block (LBBB). METHODS AND RESULTS: In 16 dogs LBBB was induced. Eight animals were followed for 16 weeks and in 8 animals BVP was started after 8 weeks. LV ...
Sedova Ksenia - - 2007
OBJECTIVE: We have investigated the local durations and sequence of repolarization in the ventricular epicardium in the rabbit under the increase of the left ventricular (LV) afterload. METHODS: The LV overload was produced by the 1-minute aortic stenosis up to systolic blood pressure of 140 mm Hg. The experiments were ...
Okumura Yasuo - - 2007
A 35-year-old man was referred to Nihon University Hospital because of repetitive ventricular tachycardia (VT) at 180-200 beats/min. QRS morphology of the VT was right bundle branch block with a northwest axis. Transthoracic echocardiography showed hypertrophic cardiomyopathy. Coronary angiography was normal and left ventriculography showed neither obstruction in the left ...
Dalsgaard Morten - - 2007
BACKGROUND: Isovolumic acceleration (IVA) as assessed by Tissue Doppler Imaging (TDI) has been proposed as a measure of left ventricular (LV) contractility. IVA is believed to be less dependent on preload than previously proposed estimates. IVA has been measured at different locations, and studies have shown conflicting results. OBJECTIVES: We ...
Schober Karsten E - - 2007
BACKGROUND: Left atrial (LA) enlargement (LAE) is a morphologic expression of the severity and chronicity of left ventricular (LV) diastolic dysfunction, volume overload, and increased atrial pressure and has diagnostic, therapeutic, and prognostic importance in cats. The noninvasive gold standard for assessing LA size is 2-dimensional echocardiography (2DE). HYPOTHESIS: ECG ...
Mizuguchi Yukio - - 2007
It is well known that arterial stiffness affects the morbidity and mortality associated with cardiovascular disease. However, there are limited data addressing the relationship between arterial stiffness and left ventricular (LV) diastolic function in patients with cardiovascular risk factors. Subclinical atherosclerosis was determined by measuring the intima-media thickness and stiffness ...
Goetze Stephan - - 2007
BACKGROUND: This acute feasibility study compared two different automatic capture detection methodologies, the reduced coupling capacitor (RCC) and the independent pace/sense (IPS) methods, for the left ventricle (LV). METHODS: LV threshold tests were performed in DDD mode, with LV-only and bi-ventricular (BiV) pacing using an external cardiac resynchronization therapy (CRT) ...
Zhong L - - 2007
We have investigated the effect of left ventricular (LV) shape on contractility and ejection function. In this study, a new contractility index is developed in terms of the wall stress (sigma*, normalized with respect to LV pressure) by means of an LV ellipsoidal model. Using cine-ventriculography data, the LV ellipsoidal ...
Masugata Hisashi - - 2007
The aim of this study was to elucidate the cardiac function in bed-bound patients following cerebrovascular accidents. In accord with the criteria for activities of daily living (ADL) of the Japanese Ministry of Health, Labour and Welfare, 51 age-matched poststroke patients without heart disease were classified into 3 groups: rank ...
Vandsburger Moriel H - - 2007
AIMS: The role of neuronal nitric oxide synthase (nNOS) in regulating contractile function remains controversial, and in regulating myocardial perfusion is uninvestigated. We used magnetic resonance imaging (MRI) to phenotype nNOS(-/-) and wild-type (WT) mice regarding left ventricular (LV) structure, baseline function, beta-adrenergic responsiveness, and perfusion reserve. METHODS AND RESULTS: ...
O'Rourke Michael F - - 2007
The human arterial system in youth is beautifully designed for its role of receiving spurts of blood from the left ventricle and distributing this as steady flow through peripheral capillaries. Central to such design is "tuning" of the heart to arterial tree; this minimizes aortic pressure fluctuations and confines flow ...
Bernheim Alain M - - 2007
BACKGROUND: Altitude-induced pulmonary hypertension has been suggested to cause left ventricular (LV) diastolic dysfunction due to ventricular interaction. In this study, we evaluate the effects of exercise- and altitude-induced increase in pulmonary artery pressures on LV diastolic function in an interventional setting investigating high-altitude pulmonary edema (HAPE) prophylaxis. METHODS: Among ...
Kim Yong Jin - - 2007
OBJECTIVE: We performed this study to validate the single-beat estimation of end-systolic elastance (E(es)) in an animal model of chronic mitral regurgitation (MR) and to use E(es) to predict postoperative left ventricular (LV) systolic function with the noninvasively derived single-beat E(es) (E(es-s)) in patients with MR. METHODS: Eight sheep with ...
Stahl Carsten - - 2007
INTRODUCTION: A large number of heart failure (HF) patients benefit from cardiac resynchronization therapy. Measurements of intrathoracic impedance (ITZ) by implantable devices correlate with intrathoracic fluid content and are used for monitoring lung edema formation in HF patients. However, intrathoracic fluid is only an indirect parameter of cardiac function. We ...
Cohn Jay N - - 2007
BACKGROUND: Isosorbide dinitrate combined with hydralazine therapy compared with placebo in patients with heart failure resulted in a sustained increase in left ventricular (LV) ejection fraction (EF) indicative of regression of LV remodeling in the first Vasodilator-Heart Failure Trial (V-HeFT-I) in patients receiving only digoxin and diuretic. In the African-American ...
Kleinman Charles S - - 2007
OBJECTIVES: To test the hypothesis that left ventricular (LV) dilation associated with pressure-restrictive ventricular septal defect (VSD) often remains stable or regresses spontaneously, calling into question the role of interventional management for such defects. STUDY DESIGN: We analyzed 96 serial echocardiograms from 33 unoperated patients with a moderate-to-large VSD with ...
Kitagawa Yutaka - - 2007
The aim of the present study was performed to determine whether a novel histone deacetylase (HDAC) inhibitor, N-(2-aminophenyl)-4-{[benzyl(2-hydroxyethyl)amino]methyl} benzamide (K-183), prevents a reversible cardiac hypertrophy induced by isoproterenol and improves left ventricular (LV) dysfunction in rats. Either isoproterenol or vehicle was infused for 3 days by osmotic minipump. One hour ...
Ozer Necla - - 2008
AIM: The present study was designed to determine the reliability of the analysis of the time difference between onset of mitral inflow and onset of early diastolic mitral annulus velocity and mean systolic strain index, and comparing them with E/E' in the detection of increased left ventricular end-diastolic pressure (LVEDP) ...
Kitahara Tatsuro - - 2007
BACKGROUND: Clinical markers to predict adverse outcome have not yet been established for patients with preserved left ventricular (LV) systolic function. The present study was designed to examine whether carboxy-terminal telopeptide of type I collagen (ICTP), a marker of collagen degradation, is useful for determining the prognosis of such patients. ...
Tozzi Rossana - - 2007
BACKGROUND: During the transition of pressure overload hypertrophy (POH) to heart failure (HF) there is intense interstitial cardiac remodeling, characterized by a complex balance between collagen deposition and degradation by matrix metalloproteases (MMPs). This study was aimed at investigating the process of cardiac remodeling during the different phases of the ...
Mulè G - - 2007
Some reports have suggested that white-coat hypertension (WCH) is associated with some features of the metabolic syndrome (MetS). These metabolic disturbances, instead of WCH per se, may potentially explain the greater extent of end-organ damage sometimes observed in WCH subjects (WCHs) when compared to normotensive individuals (NTs). The aim of ...
Donker Dirk W - - 2007
Myocardial biopsies are an increasingly important tool to unravel the molecular mechanisms of cardiac disease. We evaluate a novel minimally invasive trans-thoracic approach for left-ventricular (LV) intra-mural biopsies, which enables repetitive individual sampling in adult dogs. Forty three generally anaesthesised dogs were studied during sinus rhythm (SR, control) and multiple ...
Soliman Osama I I - - 2007
To assess mechanisms of myocardial perfusion impairment in patients with hypertrophic cardiomyopathy (HCM). Fourteen patients with obstructive HCM (mean (SD) age 53 (10) years, 11 men) underwent intravenous adenosine myocardial contrast echocardiography (MCE), positron emission tomography (PET) and cardiac catheterisation. Fourteen healthy volunteers (mean age 31 (4) years, 11 men) ...
Maceira Alicia M - - 2008
BACKGROUND: Hypertension causes cardiac morbidity and premature mortality. Accurate evaluation to exclude potentially curable causes is important. Cardiovascular Magnetic Resonance and Magnetic Resonance Angiography (CMR/CE-MRA) provide an integrated approach to the assessment of hypertensive patients - a single study can identify certain secondary causes and assess left ventricular (LV) mass ...
Strand Arne H - - 2007
Left ventricular (LV) hypertrophy is related to blood pressure level and neurohormonal factors. The authors previously demonstrated that arterial norepinephrine levels predict LV mass in middle-aged men who developed hypertension through 20 years. The aim of this 20-year prospective study was to investigate arterial vasopressin, aldosterone, and renin as long-term ...
Dwivedi Sk - - 2007
BACKGROUND: Biventricular pacing is beneficial in refractory systolic heart failure having QRS duration more than 130 msec by improving regional dysynchrony and decreasing diastolic mitral regurgitation. Current data show significant systolic dysynchrony in symptomatic systolic heart failure patients out of which nearly 40% have a QRS duration of less than ...
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