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Ventricular Volume (ventricular + volume)
Kinds of Ventricular Volume Selected AbstractsLive/Real Time Three-Dimensional Transthoracic Echocardiographic Assessment of Left Ventricular Volumes, Ejection Fraction, and Mass Compared with Magnetic Resonance ImagingECHOCARDIOGRAPHY, Issue 2 2007Xin Qi M.D. Due to reliance upon geometric assumptions and foreshortening issues, the traditionally utilized transthoracic two-dimensional echocardiography (2DTTE) has shown limitations in assessing left ventricular (LV) volume, mass, and function. Cardiac magnetic resonance imaging (MRI) has shown potential in accurately defining these LV characteristics. Recently, the emergence of live/real time three-dimensional (3D) TTE has demonstrated incremental value over 2DTTE and comparable value with MRI in assessing LV parameters. Here we report 58 consecutive patients with diverse cardiac disorders and clinical characteristics, referred for clinical MRI studies, who were evaluated by cardiac MRI and 3DTTE. Our results show good correlation between the two modalities. [source] Myocardial growth before and after birth: clinical implications,ACTA PAEDIATRICA, Issue 2 2000AM Rudolph Perinatal changes in myocardial growth have recently evoked considerable interest with regard to cardiac chamber development with congenital cardiac lesions and to myocardial development in preterm infants. It is suggested that cardiac chamber development is influenced by blood flow. Experimental pulmonary stenosis in fetal lambs may induce either greatly reduced or markedly increased right ventricular volume. Ventricular enlargement appears to be associated with a large ventricular volume load resulting from tricuspid valve regurgitation. A small competent tricuspid valve is associated with reduced flow through the ventricle due to outflow obstruction and a small right ventricle. Postnatal growth of the ventricles in congenital heart disease is discussed. Increase in myocardial mass prenatally is achieved by hyperplasia, both during normal development and when myocardial mass is increased by right ventricular outflow obstruction. Postnatally, increases in myocardial mass with normal growth, as well as with ventricular outflow obstruction, are largely due to hypertrophy of myocytes. Myocardial capillary numbers do not increase in proportion with myocyte numbers in ventricular myocardium in association with outflow obstruction. The postnatal effects of these changes in congenital heart lesions are considered. Studies in fetal lambs suggest that the late gestational increase in blood cortisol concentrations is responsible for the change in the pattern of myocardial growth after birth. The concern is raised that prenatal exposure of the premature infant to glucocorticoids, administered to the mother to attempt to prevent hyaline membrane disease in the infant, may inhibit myocyte proliferation and result in a heart with fewer than normal myocytes. This would necessitate that each myocyte would have to hypertrophy abnormally to achieve a normal cardiac mass postnatally. [source] A New Echocardiographic Index for Assessing Left Ventricular Function and Mechanism of Mitral Regurgitation and Its Relation to Other Echocardiographic IndicesECHOCARDIOGRAPHY, Issue 6 2007Cemal Sag M.D. Objective: Mitral regurgitation (MR) is a progressive disease of the mitral valve, which can be primary or functional. The assessment of left ventricular function in MR is still troublesome. In this study, we evaluated the validity of a new parameter, total dt, in patients with MR. Methods: Forty patients with severe MR constituted the study group. According to the transesophageal echocardiographic evaluation, the patients were dichotomized into two groups: (1) Primary MR; n = 21, (2) Functional MR; n = 19. The total dt was defined as the sum of time intervals from 1 msto 3 ms (positive dt) and from 3 ms to 1 ms (negative dt) on the CW Doppler recording of MR jet. It was compared to other indices of left ventricular function and left ventricular geometry, including ejection fraction, fractional shortening, myocardial performance index, coaptation distance, left ventricular volume and diameter, sphericity index, and parameters of diastolic function. Result: The total dt correlated with myocardial performance index, coaptation distance, and sphericity index. It could differentiate between primary and functional MR with an area under curve of 0.878, followed by myocardial performance index with 0.860. The total dt > 104 ms was 79% sensitive and 81% specific for discrimination. Conclusion: The total dt is useful for assessing left ventricular function and also for differentiating primary MR from functional MR. [source] Elongation Index as a New Index Determining the Severity of Left Ventricular Systolic Dysfunction and Mitral Regurgitation in Patients with Congestive Heart FailureECHOCARDIOGRAPHY, Issue 7 2005Mehmet Yokusoglu M.D. The shape of the left ventricle is an important echocardiographic feature of left ventricular dysfunction. Progression of the mitral regurgitation and consequent left ventricular remodeling is unpredictable in heart failure. Elongation index is an index of left ventricular sphericity. The surface area of the elongated ventricle is larger than that of a spherical one. The objective of this study was to assess the relation between elongation index and the degree of mitral regurgitation along with noninvasive indices of left ventricular function. Thirty-two patients (21 male, 11 female, mean age: 57 ± 6 yrs) with congestive heart failure and mitral regurgitation were included. Patients were stratified into three groups according to vena contracta width as having mild (n = 11), moderate (n = 11) and severe mitral regurgitation (n = 10). The elongation index (EI) was considered as equal to {[(left ventricular internal area-measured) , (theoretical area of the sphere with measured left ventricular volume)]/(theoretical area of the sphere with measured left ventricular volume)}. Ejection fractions by the modified Simpson rule, dP/dt and sphericity index (SI) were also recorded. The relationship between (EI), ejection fraction, dP/dt and SI reached modest statistical significance (p < 0.05). When the EI and SI were compared, the correlation was also significant (p < 0.01). The areas under the receiver operator curve of EI and SI for discriminating dP/dt < 1000 mm Hg/s were 0.833 and 0.733, respectively. In conclusion, the elongation, which defines the shape of the left ventricle, might be related to the systolic function of the left ventricle and the degree of the mitral regurgitation. Further studies are needed to demonstrate its use in other clinical entities. [source] Quantitation of Ventricular Size and Function:ECHOCARDIOGRAPHY, Issue 8 2000Accuracy of Transthoracic Rotational Scanning, Principles Two-dimensional echocardiography is a readily applicable method for the quantification of ventricular volumes. However, it is limited by assumptions regarding ventricular shape. Three-dimensional echocardiography has emerged as a more accurate and reproducible approach to ventricular volume and functional assessment compared with two-dimensional echocardiography. We review the principles of transthoracic rotational scanning and its clinical application for quantitative assessment of ventricular volume and function. [source] Asymmetrical lateral ventricular enlargement in Parkinson's diseaseEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2009M. M. Lewis Background:, A recent case report suggested the presence of asymmetrical lateral ventricular enlargement associated with motor asymmetry in Parkinson's disease (PD). The current study explored these associations further. Methods:, Magnetic resonance imaging (3T) scans were obtained on 17 PD and 15 healthy control subjects at baseline and 12,43 months later. Baseline and longitudinal lateral ventricular volumetric changes were compared between contralateral and ipsilateral ventricles in PD subjects relative to symptom onset side and in controls relative to their dominant hand. Correlations between changes in ventricular volume and United Parkinson's disease rating scale motor scores (UPDRS-III) whilst on medication were determined. Results:, The lateral ventricle contralateral to symptom onset side displayed a faster rate of enlargement compared to the ipsilateral (P = 0.004) in PD subjects, with no such asymmetry detected (P = 0.312) in controls. There was a positive correlation between ventricular enlargement and worsening motor function assessed by UPDRS-III scores (r = 0.96, P < 0.001). Discussion:, There is asymmetrical lateral ventricular enlargement that is associated with PD motor asymmetry and progression. Further studies are warranted to investigate the underlying mechanism(s), as well as the potential of using volumetric measurements as a marker for PD progression. [source] Ketamine reduce left ventricular systolic and diastolic function in patients with ischaemic heart diseaseACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2010C.-J. JAKOBSEN Objective: Ketamine may be followed by a general increase in haemodynamics and oxygen consumption, which may be of concern in patients with ischaemic heart disease. The purpose of this study was to evaluate the effect of ketamine on left ventricular (LV) systolic and diastolic function by different modalities of echocardiography and tissue Doppler imaging in patients with ischaemic heart disease. Methods and Results: Prospective observational study of 11 patients acting as own control based on echocardiographic imaging before and after bolus ketamine 0.5 mg/kg. Simpson's 2 D-volumetric method was used to quantify left ventricular volume and ejection fraction. General global LV deformation was assessed by Speckle tracking ultrasound, systolic LV longitudinal displacement was assessed by Tissue Tracking score index and the diastolic function was evaluated from changes in early-(E') and atrial (A') peak velocities during diastole. Average heart rate (34%) and blood pressure (35%) increased significantly after ketamine (P<0.0001). Mean tissue tracking score index decreased from 11.2±2.3 to 8.3±2.6 (P=0.005) and Global Speckle tracking 2D strain from 17.7±2.7 to 13.7±3.6 (P=0.0014) indicating a decrease in LV global systolic function. The E'/A' ratio decreased from 1.11±0.43 to 0.81±0.46 (P=0.044) indicating impaired relaxation. Conclusion: Different modalities of echocardiography in combination with tissue Doppler indicate both diminished systolic and diastolic function after ketamine administration in patients with ischaemic heart disease. [source] Caudate volume measurement in older adults with bipolar disorderINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 2 2004John L. Beyer Abstract Background Decreased caudate volumes have been noted in unipolar depressed subjects, especially in the elderly and those with cognitive impairment. No differences have been noted in initial studies of multi-aged bipolar subjects; however, this region has not been examined in older bipolar subjects. Methods We examined the caudate nuclei volumes of 36 older bipolar subjects (mean age 58) and 35 older controls (mean age 62) using logistic regression analyses to control for age and gender differences. Differences between late- and early-onset (age-of-onset before age 45) bipolar subjects were also examined, as well as the effect of length of illness. Results The right caudate was noted to be smaller in older bipolar subjects compared with older controls when controlled for sex and age (p,=,0.0448). No differences were noted in overall brain volume nor lateral ventricular volume between the bipolar and control subjects. Late-onset bipolar subjects had a decrease in brain volume (p,=,0.035) compared with early-onset bipolar subjects. Late-onset bipolar subjects had a decrease in the right (p,=,0.044) and total (p,=,0.04) caudate size compared with older controls. Conclusions Right caudate volume is decreased in older bipolar subjects compared to controls. Bipolar subjects with late-onset illness have significantly decreased right and total caudate volumes compared to controls. This is affected by neither the length of illness nor the age of onset. Late-onset bipolar subjects have decreased total brain volume compared with early-onset bipolar subjects. Copyright © 2004 John Wiley & Sons, Ltd. [source] Temporal Changes in Brain Volume and Cognition in a Randomized Treatment Trial of Vascular DementiaJOURNAL OF NEUROIMAGING, Issue 1 2001Joseph P. Broderick MD ABSTRACT Objective. To measure changes in brain and ischemic volume over time by magnetic resonance imaging (MRI) as part of a randomized treatment trial of vascular dementia. Methods. Participants who met criteria for vascular dementia underwent comprehensive neurological and neuropsychological testing on entrance, during, and at completion of the 1-year study. For those centers who had easily available MRI, MRI of the brain was to be performed on entry and completion of the study. Image analysis was performed on all balanced and T2-weighted MR films to determine ventricular, sulcal, ischemic, and hemispheric brain volumes. Results. Of the 105 patients who met the criteria for vascular dementia, 40 had a baseline MRI study that met protocol requirements and was of excellent image quality. The baseline ventricular volume in these 40 patients with high-quality MR correlated with most measures of cognitive and behavioral function, including the total Alzheimer's Disease Assessment Score (ADAS) (r= 0.51, P= .0024), as well as activities of daily living (r= 0.61, P= .0002). The baseline ischemic brain volume correlated well only with the gait and postural stability scale (r= 0.74, P= .009). Of the 40 participants, 25 had MRI studies at baseline and at completion of the study that were comparable and of excellent image quality. For these 25 patients, the mean ventricular volumes increased by 9% over the study year (P= .001) and the mean ischemic brain volume increased by 18% (P= .01). Temporal changes in the sulcal and nonischemic brain volume did not reach significance. None of the 14 clinical score measures changed significantly between baseline and completion of the study in these 25 patients. Conclusion. In summary, ventricular volume correlated well with cognitive measures in patients with vascular dementia and was a more sensitive marker for change during the study year than the clinical scales used in this study. This study also points out the practical limitations of brain imaging as a surrogate measure of clinical outcome in multicenter randomized treatment trials of brain disease. [source] Ventricular cerebrospinal fluid lactate is increased in chronic fatigue syndrome compared with generalized anxiety disorder: an in vivo 3.0 T 1H MRS imaging study,NMR IN BIOMEDICINE, Issue 3 2009Sanjay J. Mathew Abstract Chronic fatigue syndrome (CFS) is a controversial diagnosis because of the lack of biomarkers for the illness and its symptom overlap with neuropsychiatric, infectious, and rheumatological disorders. We compared lateral ventricular volumes derived from tissue-segmented T1 -weighted volumetric MRI data and cerebrospinal fluid (CSF) lactate concentrations measured by proton MRS imaging (1H MRSI) in 16 subjects with CFS (modified US Centers for Disease Control and Prevention criteria) with those in 14 patients with generalized anxiety disorder (GAD) and in 15 healthy volunteers, matched group-wise for age, sex, body mass index, handedness, and IQ. Mean lateral ventricular lactate concentrations measured by 1H MRSI in CFS were increased by 297% compared with those in GAD (P,<,0.001) and by 348% compared with those in healthy volunteers (P,<,0.001), even after controlling for ventricular volume, which did not differ significantly between the groups. Regression analysis revealed that diagnosis accounted for 43% of the variance in ventricular lactate. CFS is associated with significantly raised concentrations of ventricular lactate, potentially consistent with recent evidence of decreased cortical blood flow, secondary mitochondrial dysfunction, and/or oxidative stress abnormalities in the disorder. Copyright © 2008 John Wiley & Sons, Ltd. [source] Ventricular dilation: Association with gait and cognition,ANNALS OF NEUROLOGY, Issue 4 2009Walter M. Palm MD Objective Normal pressure hydrocephalus is characterized by gait impairment, cognitive impairment, and urinary incontinence, and is associated with disproportionate ventricular dilation. Here we report the distribution of ventricular volume relative to sulcal cerebrospinal fluid (CSF) volume, and the association of increasing ventricular volume relative to sulcal CSF volume with a cluster of gait impairment, cognitive impairment, and urinary incontinence in a stroke-free cohort of elderly persons from the general population. Methods Data are based on 858 persons (35.4% men; age range, 66,92 years) who participated in the Age, Gene/Environment Susceptibility,Reykjavik Study. Gait was evaluated with an assessment of gait speed. Composite scores representing speed of processing, memory, and executive function were constructed from a neuropsychological battery. Bladder function was assessed with a questionnaire. Magnetic resonance brain imaging was followed by semiautomated segmentation of intracranial CSF volume. White matter hyperintensity (WMH) volume was assessed with a semiquantitative scale. For the analysis of ventricular dilation relative to the sulcal spaces, ventricular volume was divided by sulcal CSF volume (VV/SV). Results Disproportion between ventricular and sulcal CSF volume, defined as the highest quartile of the VV/SV z score, was associated with gait impairment (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.1,3.3) and cognitive impairment (OR, 1.8; 95% CI, 1.1,3.0). We did not find an association between the VV/SV z score and bladder dysfunction. Interpretation The prevalence and severity of gait impairment and cognitive impairment increases with ventricular dilation in persons without stroke from the general population, independent of WMH volume. Ann Neurol 2009;66:485,493 [source] Prediction of the External Work of the Native Heart From the Dynamic H-Q Curves of the Rotary Blood Pumps During Left Heart BypassARTIFICIAL ORGANS, Issue 9 2010Yoshimasa Yokoyama Abstract The ventricular performance is dependent on the drainage effect of rotary blood pumps (RBPs) and the performance of RBPs is affected by the ventricular pulsation. In this study, the interaction between the ventricle and RBPs was examined using the pressure-volume (P-V) diagram of the ventricle and dynamic head pressure-bypass flow (H-Q) curves (H, head pressure: arterial pressure minus ventricular pressure vs. Q, bypass flow) of the RBPs. We first investigated the relationships in a mock loop with a passive fill ventricle, followed by validation in ex vivo animal experiments. An apical drainage cannula with a micro-pressure sensor was especially fabricated to obtain ventricular pressure, while three pairs of ultrasonic crystals placed on the heart wall were used to derive ventricular volume. The mock loop-configured ventricular apical,descending aorta bypass revealed that the external work of the ventricle expressed by the area inside the P-V diagrams (EWHeart) correlated strongly with the area inside dynamic H-Q curves (EWVAD), with the coefficients of correlation being R2 = 0.869 , 0.961. The results in the mock loop were verified in the ex vivo studies using three Shiba goats (10,25 kg in body weight), showing the correlation coefficients of R2 = 0.802 , 0.817. The linear regression analysis indicated that the increase in the bypass flow reduced pulsatility in the ventricle expressed in EWHeart as well as in EWVAD. Experimental results, both mock loop and animal studies, showed that the interaction between cardiac external work and H-Q performance of RBPs can be expressed by the relationships "EWHeart versus EWVAD." The pulsatile nature of the native heart can be expressed in the area underneath the H-Q curves of RBPs EWVAD during left heart bypass indicating the status of the level of assistance by RBPs and the native heart function. [source] Effects of Formaldehyde on Cardiovascular System in In Situ Rat HeartsBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 4 2009Daisuke Takeshita After 20,30 min. of intravenous infusion of 3.7% formaldehyde solution (FA) at 10 ,l (3.7 mg)/kg/min, normal and hypertrophic hearts showed significant decreases in left ventricle end-systolic pressure (ESP), heart rate and cardiac output per minute, indicating an acute pumping failure. Hypertrophic hearts showed significantly smaller ESP, stroke volumes and cardiac output than those in normal hearts. Systolic pressure,volume area at midrange left ventricular volume (PVAmLVV: a mechanical work capability index) was significantly smaller than that in normal hearts and per cent of mean PVAmLVVversus pre-infusion mean value in hypertrophic hearts was significantly decreased compared to normal hearts 30 min. after FA infusion. The marked decrease in pH, base excess and no changes in PaO2 and PaCO2 suggest metabolic acidosis. The correction of metabolic acidosis with 9% NaHCO3 did not influence on the acute pumping failure, indicating that metabolic acidosis did not cause it. Ultrastructural observations revealed marked dilation of the sarcoplasmic reticulum with intact sarcolemmal membranes and no disintegration of muscle myofibrils. Ryanodine receptors and calcium (Ca2+) pumps (SERCA2A) located in the sarcoplasmic reticulum have major roles in the cytosolic Ca2+ handling. Taken together, acute pumping failure by FA may derive from the impairment of Ca2+ handling in the cardiac excitation,contraction coupling. [source] Increased plasma levels of natriuretic peptide type B and A in children with congenital heart defects with left compared with right ventricular volume overload or pressure overloadCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 5 2005Daniel Holmgren Summary Aim:, Natriuretic peptide levels B (BNP) and A (ANP) have been described in children with congenital heart defects (CHD) with pressure and volume overload. However, the impact of ventricular morphology per se on natriuretic peptide levels has not been reported. The aim of the present study was to evaluate plasma BNP and ANP in children with CHD with left or right ventricular volume or pressure overload. Methods and results:, Plasma BNP and ANP were analysed in 61 children, median age 3·1 (0·3,16·2) years. Haemodynamic load was evaluated by echo-Doppler and/or catheterization measurements and classified as: pressure overload of the right (RV pressure) or left (LV pressure) ventricle, or volume overload of the right (RV volume) or left (LV volume) ventricle, of a sufficient degree to indicate surgery/catheter intervention. Twenty-three children, with a median age of 1·1 (0·1,8·3) years, without heart disease, served as controls for the natriuretic peptide measurements. Children in the LV volume group had significantly higher BNP and ANP values, 55·4 ng l,1 (10·7,352) and 164 (31·8,346), than children in the RV volume, 15·6 (0·0,105·1) and 57·2 (11·3,234·1), LV pressure, 6·8 (0·7,170) and 40·8 (12·6,210), and RV pressure, 18·0 (5·0,29·1) and 69·3 (8·7,182), groups respectively (P<0·0001). The values in the LV pressure group were close to the values in the Control group, 4·7 (0·0,17·7) and 32·9 (11·7,212·1), respectively (P = 0·051 and P = 0·378, respectively). Conclusions:, Plasma concentrations of BNP and ANP were higher in children with CHD with left ventricular volume overload compared with right ventricular volume overload or pressure overload. [source] Right Ventricular Function in Congenital Heart Defects Assessed by Regional Wall MotionCONGENITAL HEART DISEASE, Issue 3 2010FSCAI, Michael R. Nihill MB ABSTRACT Objectives., To develop a simple method to assess right ventricular function by angiography. Background., Conventional methods of evaluating right ventricular function are inaccurate, cumbersome, and expensive. Methods., We analyzed biplane right ventricular angiograms taken in the posterior,anterior and lateral projections using software to measure right ventricular volumes and regional wall motion in 78 patients with normal hearts (n = 29), atrial septal defects (ASD n = 13), pulmonary valve stenosis (PVS n = 21), and postoperative atrial switch patients (n = 15). We also measured the shortening fraction (SF) from the midtricuspid annulus to the septum and correlated various angiographic measurements with the right ventricular (RV) ejection fraction. Results., The volume-overloaded patients (ASD) had larger end diastolic volumes and increased SF compared with normal patients, while the pressure-loaded patients (PVS) had normal volumes and SF. The postoperative atrial switch patients had decreased systolic function and increased end diastolic volume. The SF for all of the patients correlated with the ejection fraction (r= 0.785, P, .0001). Conclusions., A simple measurement of the end diastolic and end systolic distance from the midtricuspid annulus to the septum (SF) provides a good index of RV function by angiography and correlates well with RV ejection fraction. [source] Effect of reduced total blood volume on left ventricular volumes and kinetics in type 2 diabetesACTA PHYSIOLOGICA, Issue 1 2010S. Lalande Abstract Aim:, Although impaired left ventricular (LV) diastolic function is commonly observed in patients with type 2 diabetes, it remains unclear whether the impairment is caused by altered LV relaxation or changes in LV preload. The purpose of this study was to examine the influence of LV function and LV loading conditions on stroke volume in men with type 2 diabetes. Methods:, Cardiac magnetic resonance imaging scans were performed in eight men with type 2 diabetes and 11 non-diabetic men matched for age, weight and physical activity level. Total blood volume was determined with the Evans blue dye dilution technique. Results:, End-diastolic volume (EDV), the ratio of peak early to late mitral inflow velocity (E/A) and stroke volume were lower in men with type 2 diabetes than in non-diabetic individuals. Peak filling rate and peak ejection rate were not different between diabetic and non-diabetic individuals; however, men with type 2 diabetes had proportionally longer systolic duration than non-diabetic individuals. Heart rate was higher and total blood volume was lower in men with type 2 diabetes. The lower total blood volume was correlated with a lower EDV in men with type 2 diabetes. Conclusions:, Men with type 2 diabetes have an altered cardiac cycle and lower end-diastolic and stroke volume. A lower total blood volume and higher heart rate in men with type 2 diabetes suggest that changes in LV preload, independent of changes in LV relaxation or contractility, influence LV diastolic filling and stroke volume in this population. [source] Quantitation of Ventricular Size and Function:ECHOCARDIOGRAPHY, Issue 8 2000Accuracy of Transthoracic Rotational Scanning, Principles Two-dimensional echocardiography is a readily applicable method for the quantification of ventricular volumes. However, it is limited by assumptions regarding ventricular shape. Three-dimensional echocardiography has emerged as a more accurate and reproducible approach to ventricular volume and functional assessment compared with two-dimensional echocardiography. We review the principles of transthoracic rotational scanning and its clinical application for quantitative assessment of ventricular volume and function. [source] Humoral and cardiac effects of TIPS in cirrhotic patients with different "effective" blood volumeHEPATOLOGY, Issue 6 2003Francesco Salerno M.D. The aim of this study was to evaluate the cardiac effects of transjugular intrahepatic portosystemic shunts (TIPS) in cirrhotic patients with different effective blood volume. Two-dimensional echocardiography was performed before and 7 and 28 days after TIPS insertion in 7 cirrhotic patients with PRA <4 ng/mL/h (group A, normal effective blood volume) and 15 with PRA >4 ng/mL/h (group B, reduced effective blood volume). Before TIPS, most cirrhotic patients showed diastolic dysfunction as indicated by reduced early maximal ventricular filling velocity (E)/late filling velocity (A) ratio. Patients of group B differed from patients of group A because of smaller left ventricular volumes and stroke volume, indicating central underfilling. After TIPS insertion, portal decompression was associated with a significant increase of cardiac output (CO) and a decrease of peripheral resistances. The most important changes were recorded in patients of group B, who showed a significant increase of both the end-diastolic left ventricular volumes and the E/A ratio and a significant decrease of PRA. In conclusion, these results show that the hemodynamic effects of TIPS differ according to the pre-TIPS effective blood volume. Furthermore, TIPS improves the diastolic cardiac function of cirrhotic patients with effective hypovolemia. This result is likely due to a TIPS-related improvement of the fullness of central blood volume. [source] Temporal Changes in Brain Volume and Cognition in a Randomized Treatment Trial of Vascular DementiaJOURNAL OF NEUROIMAGING, Issue 1 2001Joseph P. Broderick MD ABSTRACT Objective. To measure changes in brain and ischemic volume over time by magnetic resonance imaging (MRI) as part of a randomized treatment trial of vascular dementia. Methods. Participants who met criteria for vascular dementia underwent comprehensive neurological and neuropsychological testing on entrance, during, and at completion of the 1-year study. For those centers who had easily available MRI, MRI of the brain was to be performed on entry and completion of the study. Image analysis was performed on all balanced and T2-weighted MR films to determine ventricular, sulcal, ischemic, and hemispheric brain volumes. Results. Of the 105 patients who met the criteria for vascular dementia, 40 had a baseline MRI study that met protocol requirements and was of excellent image quality. The baseline ventricular volume in these 40 patients with high-quality MR correlated with most measures of cognitive and behavioral function, including the total Alzheimer's Disease Assessment Score (ADAS) (r= 0.51, P= .0024), as well as activities of daily living (r= 0.61, P= .0002). The baseline ischemic brain volume correlated well only with the gait and postural stability scale (r= 0.74, P= .009). Of the 40 participants, 25 had MRI studies at baseline and at completion of the study that were comparable and of excellent image quality. For these 25 patients, the mean ventricular volumes increased by 9% over the study year (P= .001) and the mean ischemic brain volume increased by 18% (P= .01). Temporal changes in the sulcal and nonischemic brain volume did not reach significance. None of the 14 clinical score measures changed significantly between baseline and completion of the study in these 25 patients. Conclusion. In summary, ventricular volume correlated well with cognitive measures in patients with vascular dementia and was a more sensitive marker for change during the study year than the clinical scales used in this study. This study also points out the practical limitations of brain imaging as a surrogate measure of clinical outcome in multicenter randomized treatment trials of brain disease. [source] Magnetic Resonance Microscopy Defines Ethanol-Induced Brain Abnormalities in Prenatal Mice: Effects of Acute Insult on Gestational Day 8ALCOHOLISM, Issue 6 2009Scott E. Parnell Background:, Magnetic resonance microscopy (MRM), magnetic resonance imaging (MRI) at microscopic levels, provides unprecedented opportunities to aid in defining the full spectrum of ethanol's insult to the developing brain. This is the first in a series of reports that, collectively, will provide an MRM-based atlas of developmental stage-dependent structural brain abnormalities in a Fetal Alcohol Spectrum Disorders (FASD) mouse model. The ethanol exposure time and developmental stage examined for this report is gestational day (GD) 8 in mice, when the embryos are at early neurulation stages; stages present in humans early in the fourth week postfertilization. Methods:, For this study, pregnant C57Bl/6J mice were administered an ethanol dosage of 2.8 g/kg intraperitoneally at 8 days, 0 hour and again at 8 days, 4 hours postfertilization. On GD 17, fetuses that were selected for MRM analyses were immersion fixed in a Bouin's/Prohance® solution. Control fetuses from vehicle-treated dams were stage-matched to those that were ethanol-exposed. The fetal mice were scanned ex vivo at 7.0 T and 512 × 512 × 1024 image arrays were acquired using 3-D spin warp encoding. The resulting 29 ,m (isotropic) resolution images were processed using ITK-SNAP, a 3-D segmentation/visualization tool. Linear and volume measurements were determined for selected brain, head, and body regions of each specimen. Comparisons were made between control and treated fetuses, with an emphasis on determining (dis)proportionate changes in specific brain regions. Results:, As compared with controls, the crown-rump lengths of stage-matched ethanol-exposed GD 17 fetuses were significantly reduced, as were brain and whole body volumes. Volume reductions were notable in every brain region examined, with the exception of the pituitary and septal region, and were accompanied by increased ventricular volumes. Disproportionate regional brain volume reductions were most marked on the right side and were significant for the olfactory bulb, hippocampus, and cerebellum; the latter being the most severely affected. Additionally, the septal region and the pituitary were disproportionately large. Linear measures were consistent with those of volume. Other dysmorphologic features noted in the MR scans were choanal stenosis and optic nerve coloboma. Conclusions:, This study demonstrates that exposure to ethanol occurring in mice at stages corresponding to the human fourth week postfertilization results in structural brain abnormalities that are readily identifiable at fetal stages of development. In addition to illustrating the utility of MR microscopy for analysis of an FASD mouse model, this work provides new information that confirms and extends human clinical observations. It also provides a framework for comparison of structural brain abnormalities resulting from ethanol exposure at other developmental stages and dosages. [source] Global,Local Interference is Related to Callosal Compromise in Alcoholism: A Behavior-DTI Association StudyALCOHOLISM, Issue 3 2009Eva M. Müller-Oehring Background:, Visuospatial ability is a multifactorial process commonly impaired in chronic alcoholism. Identification of which features of visuospatial processing are affected and which are spared in alcoholism, however, has not been clearly determined. We used a global,local paradigm to assess component processes of visuospatial ability and MR diffusion tensor imaging (DTI) to examine whether alcoholism-related microstructural degradation of the corpus callosum contributes to disruption of selective lateralized visuospatial and attention processes. Methods:, A hierarchical letter paradigm was devised, where large global letters were composed of small local letters. The task required identification of target letters among distractors presented at global, local, both, or neither level. Attention was either selectively directed to global or local levels or divided between levels. Participants were 18 detoxified chronic alcoholics and 22 age-matched healthy controls. DTI provided quantitative assessment of the integrity of corpus callosal white matter microstructure. Results:, Alcoholics generally had longer reaction times than controls but obtained similar accuracy scores. Both groups processed local targets faster than global targets and showed interference from targets at the unattended level. Alcoholics exhibited moderate compromise in selectively attending to the global level when the global stimuli were composed of local targets. Such local interference was less with longer abstinence. Callosal microstructural integrity compromise predicted degree of interference from stimulus incongruency in the alcoholic group. This relationship was not observed for lateral or third ventricular volumes, which are measures of nonspecific cortical volume deficits. Conclusion:, Global,local feature perception was generally spared in abstinent chronic alcoholics, but impairments were observed when directing attention to global features and when global and local information interfered at stimulus or response levels. Furthermore, the interference-callosal integrity relationship in alcoholics indicates that compromised visuospatial functions include those requiring bilateral integration of information. [source] Ventricular cerebrospinal fluid lactate is increased in chronic fatigue syndrome compared with generalized anxiety disorder: an in vivo 3.0 T 1H MRS imaging study,NMR IN BIOMEDICINE, Issue 3 2009Sanjay J. Mathew Abstract Chronic fatigue syndrome (CFS) is a controversial diagnosis because of the lack of biomarkers for the illness and its symptom overlap with neuropsychiatric, infectious, and rheumatological disorders. We compared lateral ventricular volumes derived from tissue-segmented T1 -weighted volumetric MRI data and cerebrospinal fluid (CSF) lactate concentrations measured by proton MRS imaging (1H MRSI) in 16 subjects with CFS (modified US Centers for Disease Control and Prevention criteria) with those in 14 patients with generalized anxiety disorder (GAD) and in 15 healthy volunteers, matched group-wise for age, sex, body mass index, handedness, and IQ. Mean lateral ventricular lactate concentrations measured by 1H MRSI in CFS were increased by 297% compared with those in GAD (P,<,0.001) and by 348% compared with those in healthy volunteers (P,<,0.001), even after controlling for ventricular volume, which did not differ significantly between the groups. Regression analysis revealed that diagnosis accounted for 43% of the variance in ventricular lactate. CFS is associated with significantly raised concentrations of ventricular lactate, potentially consistent with recent evidence of decreased cortical blood flow, secondary mitochondrial dysfunction, and/or oxidative stress abnormalities in the disorder. Copyright © 2008 John Wiley & Sons, Ltd. [source] Quantification of left ventricular volumes and ejection fraction from gated 99mTc-MIBI SPECT: MRI validation of the exini heart software packageCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 2 2009Oliver H. Winz Summary The aim of the study was to validate the accuracy of the exini heart software (exini) package in assessing left ventricular end-diastolic/systolic volumes (EDV, ESV) and ejection fraction (LVEF) from gated 99mTc-MIBI single-photon emission tomography (SPECT). Cardiac magnetic resonance imaging (cMRI) was used as reference. Furthermore, effects of perfusion defects and image quality in SPECT on correlation between gated SPECT and magnetic resonance imaging were investigated. Methods:, Seventy patients were examined using gated SPECT (rest study, eight gates per cardiac cycle). EDV, ESV and LVEF were calculated from gated SPECT using exini. Directly before or after SPECT, cMRI (20 gates cardiac per cycle) was performed. EDV, ESV and LVEF were calculated using Simpson's rule. Perfusion defects were quantified using the summed-rest-score (SRS). Total number of myocardial counts were used to rate image quality. Results:, Correlation between results of gated SPECT and cMRI was high for EDV (R = 0·89) and ESV (R = 0·94) and good for LVEF (R = 0·78). ESV (exini 54 ± 31 ml versus cMRI 57 ± 34 ml) and LVEF (exini 62·9 ± 11·7% versus cMRI 60·6 ± 13·9%) did not differ significantly whereas exini overestimated EDV significantly compared with cMRI (exini 144 ± 41 ml versus cMRI 137 ± 36 ml; P<0·005). No correlation was found between absolute differences of the results given by gated SPECT and cMRI and SRS or total myocardial counts (R < 0·18). Conclusion:, End-diastolic volume, ESV and LVEF calculated from gated SPECT using exini agree with cMRI over a wide range of values. Correlation between both the methods was good for EDV and ESV, and acceptable for LVEF. No relevant influence of image quality or SRS on the accuracy of exini results was found. [source] Validation of a new automated method for analysis of gated-SPECT imagesCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 3 2006Milan Lomsky Summary We recently presented a new method for quantification of CArdiac FUnction , denoted CAFU , as the first step in the development of an automated method for integrated interpretation of gated myocardial perfusion single photon emission computed tomography (SPECT) images. The aim of this study was to validate CAFU in the assessment of global and regional function of the left ventricle. Quantitative gated-SPECT (QGS), the most widely used software package for quantification of gated-SPECT images, was used as reference method for the measurements of ejection fraction (EF) and ventricular volumes, and visual analysis by an experienced physician was used as reference method for the measurements of regional wall motion and thickening. Two different groups of consecutive patients referred for myocardial perfusion scintigraphy were studied. Global function was evaluated in 316 patients and regional function in 49 other patients. The studies were performed using a 2-day stress/rest 99 m-Tc-sestamibi protocol. A good correlation was found between EF values from QGS and CAFU (EF CAFU = 0·84 EF QGS + 13, r = 0·94), but CAFU values were on average 4 EF points higher than QGS values. With CAFU the segments with normal thickening according to the physician showed significantly higher thickening values (in all parts of the myocardium) compared to the segments classified as having abnormal thickening. In conclusion, this study demonstrates that CAFU can be used to quantify global and regional function in gated-SPECT images. This is an important step in our development of an automated method for integrated interpretation of gated-SPECT myocardial perfusion scintigraphy studies. [source] Evaluation of left ventricular volumes and ejection fraction by automated gated myocardial SPECT versus cardiovascular magnetic resonanceCLINICAL PHYSIOLOGY AND FUNCTIONAL IMAGING, Issue 3 2005Eva Persson Summary Background:, Electrocardiogram-gated myocardial single-photon emission computed tomography (SPECT) with 99mTc-tetrofosmin allows simultaneous evaluation of myocardial perfusion and function. In this study, left ventricular volumes, ejection fraction (LVEF), and left ventricular wall volume (LVWV) derived from gated SPECT were compared with measurements from cardiovascular magnetic resonance (CMR), performed within a few hours. Methods:, The study population included 55 patients with known or suspected coronary artery disease, including 13 patients with recent acute myocardial infarction. End-diastolic (EDV) and end-systolic (ESV) volumes, LVEF and LVWV were derived automatically from gated SPECT using commercially available software (QGS). In the CMR studies, manually delineated endocardial and epicardial borders on short-axis slices were used to calculate the volumes. Results:, Gated SPECT underestimated EDV by 35 ± 14 ml (mean ± SD) (P<0·001), ESV by 10 ± 13 ml (P<0·001), and LVEF by 4 ± 7 percentage points (P<0·001). There were no systematic difference in EDV, ESV or LVEF between the methods. SPECT underestimated LVWV by 49 ± 30 ml (P<0·001), with a trend towards increasing underestimation by SPECT for larger wall volumes. Conclusion:, These findings show that gated SPECT slightly underestimates EDV, ESV and LVEF compared with CMR. This underestimation is systematic, however, indicating that ventricular volumes derived from gated SPECT are robust enough to guide clinical management. Estimates of LVWV in patients with large wall volumes are less accurate. [source] | ||||||||||||||||||||||