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LV Volume (lv + volume)
Selected AbstractsFeasibility of Biventricular Pacing in Patients With Recent Myocardial Infarction: Impact on Ventricular RemodelingCONGESTIVE HEART FAILURE, Issue 1 2007Eugene S. Chung MD To test the hypothesis that biventricular pacing after a myocardial infarction with reduced ejection fraction can attenuate left ventricular (LV) remodeling, the authors studied 18 patients (myocardial infarction within 30,45 days, ejection fraction ,30%, narrow QRS) randomized to biventricular therapy (biventricular therapy + defibrillator) (biventricular group) or implantable cardioverter-defibrillator alone (control group). At 1, 6, and 12 months, there were no differences in functional or clinical parameters (New York Heart Association, quality of life, 6-minute walk). Twelve-month LV volume remained stable in the biventricular group, but increased in the control group (median LV end-diastolic volume increase, 6.5 mL in biventricular vs 35 mL in control; P=.03; median LV end-diastolic volume decrease, 5.5 mL in biventricular vs 30.5-mL increase in control; P=.11). Biventricular therapy also prevented an increase in sphericity index at 12 months (median, ,2% in biventricular vs 37% in control; P=.06). Delivery of biventricular therapy early after myocardial infarction appears safe and feasible and may attenuate subsequent LV dilation. [source] An Echocardiographic Analysis of the Long-Term Effects of Carvedilol on Left Ventricular Remodeling, Systolic Performance, and Ventricular Filling Patterns in Dilated CardiomyopathyECHOCARDIOGRAPHY, Issue 7 2005Peter S. Rahko M.D. Background: The long-term clinical benefit of beta blockade is well recognized, but data quantifying long-term effects of beta blockade on remodeling of the left ventricle (LV) is limited. Methods: This consecutive series evaluates the long-term response of the LV to the addition of carvedilol to conventional therapy for dilated cardiomyopathy. There were 33 patients who had a LV ejection fraction <45%, LV enlargement and symptomatic heart failure. Quantitative Doppler echocardiography was performed at baseline 6, 12, 24, and 36 months after initiation of carvedilol to evaluate LV ejection fraction, LV volume, wall stress, mass, regional function, and diastolic performance. Results: Compared to baseline there was a significant and sustained reduction in end-systolic volume and end-systolic wall stress with a corresponding improvement in LV ejection fraction. The LV mass did not decline but relative wall thickness increased toward normal. An analysis of regional wall motion responses showed an improvement in all areas, particularly the apical, septal, and lateral walls that was significantly more frequent in patients with a nonischemic etiology. Filling patterns of the LV remained abnormal throughout the study but changed with therapy suggesting a decline in filling pressures. These changes were sustained for 3 years. Conclusion: (1) The addition of carvedilol to conventional therapy for a dilated cardiomyopathy significantly improves LV ejection fraction and reduces LV end-systolic volume and wall stress for at least 3 years, (2) the response to 6 months of treatment predicts the long-term response, (3) the typical response is partial improvement of the LV, complete return to normal size, and function is uncommon, and (4) abnormalities of LV filling persist in virtually all patients throughout the course of treatment. [source] High thoracic epidural analgesia improves left ventricular function in patients with ischemic heartACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 5 2009C.-J. JAKOBSEN Background: In patients with ischemic heart disease, high thoracic epidural analgesia (HTEA) has been proposed to improve myocardial function. Tissue Doppler Imaging (TDI) is a tool for quantitative determination of myocardial systolic and diastolic velocities and a derivative of TDI is tissue tracking (TT), which allows quantitative assessment of myocardial systolic longitudinal displacement during systole. The purpose of this study was to evaluate the effect of thoracic epidural analgesia on left ventricular (LV) systolic and diastolic function by means of two-dimensional (2D) echocardiography and TDI in patients with ischemic heart disease. Methods: The effect of a high epidural block (at least Th1,Th5) on myocardial function in patients (N=15) with ischemic heart disease was evaluated. Simpson's 2D volumetric method was used to quantify LV volume and ejection fraction. Systolic longitudinal displacement was assessed by the TT score index and the diastolic function was evaluated from changes in early (E,) and atrial (A,) peak velocities during diastole. Results: After HTEA, 2D measures of left ventricle function improved significantly together with the mean TT score index [from 5.87 ± 1.53 to 6.86 ± 1.38 (P<0.0003)], reflecting an increase in LV global systolic function and longitudinal systolic displacement. The E,/A, ratio increased from 0.75 ± 0.27 to 1.09 ± 0.32 (P=0.0026), indicating improved relaxation. Conclusion: A 2D-echocardiography in combination with TDI indicates both improved systolic and diastolic function after HTEA in patients with ischemic heart disease. [source] Design of an Artificial Left Ventricular Muscle: An Innovative Way to Actuate Blood Pumps?ARTIFICIAL ORGANS, Issue 6 2009Benjamin Van Der Smissen Abstract Blood pumps assist or take over the pump function of a failing heart. They are essentially activated by a pusher plate, a pneumatic compression of collapsible sacs, or they are driven by centrifugal pumps. Blood pumps relying upon one of these actuator mechanisms do not account for realistic wall deformation. In this study, we propose an innovative design of a blood pump actuator device which should be able to mimic fairly well global left ventricular (LV) wall deformation patterns in terms of circumferential and longitudinal contraction, as well as torsion. In order to reproduce these basic wall deformation patterns in our actuator device, we designed a novel kind of artificial LV "muscle" composed of multiple actively contracting cells. Its contraction is based on a mechanism by which pressurized air, inside such a cell, causes contraction in one direction and expansion perpendicular to this direction. The organization and geometry of the contractile cells within one artificial LV muscle, the applied pressure in the cells, and the governing LV loading conditions (preload and afterload) together determine the global deformation of the LV wall. Starting from a simple plastic bag, an experimental model based on the abovementioned principle was built and connected to a lumped hydraulic model of the vascular system (including compliance and resistance). The wall deformation pattern of this device was validated visually and its pump performance was studied in terms of LV volume and pressure and heart rate. Our experimental results revealed (i) a global LV motion resembling a real LV, and (ii) a close correlation between our model and a real LV in terms of end-systolic volume and pressure, end-diastolic volume and pressure, stroke volume, ejection fraction and pressure-volume relationship. Our proposed model appears promising and it can be considered as a step forward when compared to currently applied actuator mechanisms, as it will likely result in more physiological intracavity blood flow patterns. [source] Acute left ventricular failure after large volume pericardiocentesisCLINICAL CARDIOLOGY, Issue 12 2003A. Chamoun M.D. Abstract This paper reports on two cases of large volume pericardiocentesis followed by transient severe acute left ventricular (LV) systolic failure in the absence of any prior history of LV dysfunction. Acute LV volume overload due to inter-ventricular volume mismatch is believed by most authors to be the cause for this phenomenon. Another plausible physiopathologic explanation is the acute increase in "wall stress" (Laplace's law) due to acute distention of the cardiac chambers secondary to a sudden increase in venous return at high filling pressures, combined with a "vacuum" effect of the evacuated pericardial space. [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] Mitral Regurgitation Associated with Mitral Annular Dilation in Patients with Lone Atrial Fibrillation: An Echocardiographic StudyECHOCARDIOGRAPHY, Issue 8 2009Takashi Kihara M.D. Background: Whether and how lone atrial fibrillation (AF) is associated with functional mitral regurgitation (MR) remain unclear. Method: We studied 12 lone AF patients without left ventricular (LV) dysfunction and/or dilatation, who underwent mitral valve annuloplasty for functional mitral regurgitation (MR). Ten lone AF patients without MR served as controls. Results: Lone AF Patients with MR had a greater mitral valve annular area and left atrial area than those without MR. There were no differences in LV volumes or LV ejection fraction. Conclusions: Therefore, we concluded that left atrial dilation and corresponding mitral annular dilation may cause MR in lone AF patients without LV dysfunction and/or dilatation. [source] Volume Reduction Surgery for End-Stage Ischemic Heart DiseaseECHOCARDIOGRAPHY, Issue 7 2002Takahiro Shiota M.D. The Dor procedure, or infarction excision surgery, was first used in 1984. It is a surgical treatment option for patients with end-stage ischemic heart failure. In a recently published multicenter study that included a total of 439 patients, average ejection fraction increased from 29 ± 10% to 39 ± 12% after surgery. In our experience, the overall survival rate 18 months after surgery is 89%, and the preoperative mortality rate is 6.6%. These results are similar to the previous reports from Dor,s group, which confirmed the certain value of the surgery. Echocardiography, including intraoperative transesophageal echocardiography, plays an important role in clarifying cardiac anatomies, absolute left ventricular (LV) volumes, ejection fraction, and mitral regurgitation in patients with ischemic heart failure undergoing this surgery. With the development of ultrasound and computer technology, three-dimensional echocardiography may be preferred when evaluating the surgical results, including determination of absolute LV volumes. Communication between experienced cardiac surgeons and echocardiographers in the operating room is essential for successful outcomes and reliable evaluation of the surgery. [source] Endurance Exercise Training in Older Patients with Heart Failure: Results from a Randomized, Controlled, Single-Blind TrialJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 11 2009Peter H. Brubaker PhD OBJECTIVES: To test the hypothesis that exercise training (ET) improves exercise capacity and other clinical outcomes in older persons with heart failure with reduced ejection fraction (HfrEF). DESIGN: Randomized, controlled, single-blind trial. SETTING: Outpatient cardiac rehabilitation program. PARTICIPANTS: Fifty-nine patients aged 60 and older with HFrEF recruited from hospital records and referring physicians were randomly assigned to a 16-week supervised ET program (n=30) or an attention-control, nonexercise, usual care control group (n=29). INTERVENTION: Sixteen-week supervised ET program of endurance exercise (walking and stationary cycling) three times per week for 30 to 40 minutes at moderate intensity regulated according to heart rate and perceived exertion. MEASUREMENTS: Individuals blinded to group assignment assessed four domains pivotal to HFrEF pathophysiology: exercise performance, left ventricular (LV) function, neuroendocrine activation, and health-related quality of life (QOL). RESULTS: At follow-up, the ET group had significantly greater exercise time and workload than the control group, but there were no significant differences between the groups for the primary outcomes: peak exercise oxygen consumption (VO2 peak), ventilatory anaerobic threshold (VAT), 6-minute walk distance, QOL, LV volumes, EF, or diastolic filling. Other than serum aldosterone, there were no significant differences after ET in other neuroendocrine measurements. Despite a lack of a group "training" effect, a subset (26%) of individuals increased VO2 peak by 10% or more and improved other clinical variables as well. CONCLUSION: In older patients with HFrEF, ET failed to produce consistent benefits in any of the four pivotal domains of HF that were examined, although the heterogeneous response of older patients with HFrEF to ET requires further investigation to better determine which patients with HFrEF will respond favorably to ET. [source] Effect of Left Ventricular Lead Concordance to the Delayed Contraction Segment on Echocardiographic and Clinical Outcomes after Cardiac Resynchronization TherapyJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2009JEFFREY W.H. FUNG M.D. Introduction: The optimal left ventricular (LV) pacing site for cardiac resynchronization therapy (CRT) is unclear. The current study aims to explore the clinical significance of LV lead concordance to delayed contraction segment in CRT. Methods and Results: Concordant LV lead position was defined as the lead tip located by fluoroscopy at or immediately adjacent to the LV segment with latest contraction determined by tissue Doppler imaging. Echocardiographic and clinical outcomes among 101 consecutive patients with or without concordant LV lead positions were compared. There was no significant difference in changes in LV volumes and clinical parameters between patients with concordant (n = 46) or nonconcordant (n = 55) LV lead positions at 3 and 6 months. In multivariate analysis, the baseline asynchrony index (,= 1.092, 95% CI: 1.050,1.114; P < 0.001), but not LV lead concordance, was the only independent predictor of LV reverse remodeling. By Cox regression analysis, ischemic etiology, and LV reverse remodeling, but not LV lead concordance, were independent predictors of mortality (,= 2.475, 95% CI: 1.183,5.178; P = 0.016, and ,= 0.272, 95% CI: 0.130,0.567; P < 0.001, respectively), cardiovascular hospitalization (,= 1.551, 95% CI: 1.032,2.333; P = 0.035, and ,= 0.460, 95% CI: 0.298,0.708; P < 0.001, respectively), and heart failure hospitalization (,= 0.486, 95% CI: 0.320,0.738; P = 0.001 for LV reverse remodeling). Conclusion: LV lead concordance to the delayed contraction segment may not be a major determining factor for favorable echocardiographic and clinical outcomes after CRT. [source] Myocardial iron clearance during reversal of siderotic cardiomyopathy with intravenous desferrioxamine: a prospective study using T2* cardiovascular magnetic resonanceBRITISH JOURNAL OF HAEMATOLOGY, Issue 3 2004Lisa J. Anderson Summary Heart failure from iron overload causes 71% of deaths in thalassaemia major, yet reversal of siderotic cardiomyopathy has been reported. In order to determine the changes in myocardial iron during treatment, we prospectively followed thalassaemia patients commencing intravenous desferrioxamine for iron-induced cardiomyopathy during a 12-month period. Cardiovascular magnetic resonance assessments were performed at baseline, 3, 6 and 12 months of treatment, and included left ventricular (LV) function and myocardial and liver T2*, which is inversely related to iron concentration. One patient died. The six survivors showed progressive improvements in myocardial T2* (5·1 ± 1·9 to 8·1 ± 2·8 ms, P = 0·003), liver iron (9·6 ± 4·3 to 2·1 ± 1·5 mg/g, P = 0·001), LV ejection fraction (52 ± 7·1% to 63 ± 6·4%, P = 0·03), LV volumes (end diastolic volume index 115 ± 17 to 96 ± 3 ml, P = 0·03; end systolic volume index 55 ± 16 to 36 ± 6 ml, P = 0·01) and LV mass index (106 ± 14 to 95 ± 13, P = 0·01). Iron cleared more slowly from myocardium than liver (5·0 ± 3·3% vs. 39 ± 23% per month, P = 0·02). These prospective data confirm that siderotic heart failure is often reversible with intravenous iron chelation with desferrioxamine. Myocardial T2* improves in concert with LV volumes and function during recovery, but iron clearance from the heart is considerably slower than from the liver. [source] | ||||||||||