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Search Results: 1 - 10 of 1711 matches for " Majid Kiavar "
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Echocardiographic Findings in Thalassemia Major: A Case Report and Literature Review
Anita Sadeghpour,Majid Kiavar,Azin Alizadehasl,Rasoul Azarfarin
Journal of Cardiovascular and Thoracic Research , 2012,
Abstract: We introduce a 28-year-old woman with Thalassemia major whose clinical assessment, including two-dimensional Doppler echocardiography demonstrated severe left ventricular hypertrophy with severe biventricular enlargement and systolic dysfunction as well as severe diastolic dysfunction. We hereby address these issues from an echocardiographic point of view.
Timely Diagnosis of Left Ventricular Posterior Wall Rupture by Echocardiography: A Case Report
Maryam Esmaeilzadeh,Ahmad Mirdamadi,Majid Kiavar,Gholamreza Omrani
Journal of Tehran University Heart Center , 2010,
Abstract: Left ventricular free wall rupture is responsible for up to 10% of in-hospital deaths following myocardial infarction. It is mainly associated with posterolateral myocardial infarction, and its antemortem diagnosis is rarely made.One of the medical complications of myocardial infarction is the rupture of the free wall, which occurs more frequently in the anterolateral wall in hypertensives, women, and those with relatively large transmural myocardial infarction usually 1-4 days after myocardial infarction.We herein present the case of a 66-year-old man suffering inferior wall myocardial infarction with abrupt hemodynamicdecompensation 9 days after myocardial infarction. Emergent transthoracic echocardiography revealed massive pericardialeffusion with tamponade, containing a large elongated mass measuring 1 × 8cm suggestive of hematoma secondary to cardiac rupture. In urgent cardiac surgery, the posterior wall between the left coronary artery branches was ruptured.
Echocardiographic evaluation of mitral geometry in functional mitral regurgitation
Anita Sadeghpour, Firoozeh Abtahi, Majid Kiavar, Maryam Esmaeilzadeh, Niloofar Samiei, Seyedeh Ojaghi, Hooman Bakhshandeh, Majid Maleki, Feridoun Noohi, Ahmad Mohebbi
Journal of Cardiothoracic Surgery , 2008, DOI: 10.1186/1749-8090-3-54
Abstract: Functional mitral regurgitation (FMR) occurs as a consequence of systolic left ventricular (LV) dysfunction caused by ischemic or nonischemic cardiomyopathy. Mitral valve repair in ischemic MR is one of the most controversial topic in surgery and proper repairing requires an understanding of its mechanisms, as the exact mechanism of FMR are not well defined.136 consecutive patients mean age of 55 with systolic LV dysfunction and FMR underwent complete echocardiography and after assessing MR severity, LV volumes, Ejection Fraction, LV sphericity index, C-Septal distance, Mitral valve annulus, Interpapillary distance, Tenting distance and Tenting area were obtained.There was significant association between MR severity and echocardiogarphic indices (all p values < 0.001). Severe MR occurred more frequently in dilated cardiomyopathy (DCM) patients compared to ischemic patients, (p < 0.001). Based on the model, only Mitral valve tenting distance (TnD) (OR = 22.11, CI 95%: 14.18 – 36.86, p < 0.001) and Interpapillary muscle distance (IPMD), (OR = 6.53, CI 95%: 2.10 – 10.23, p = 0.001) had significant associations with MR severity.Mitral annular dimensions and area, C-septal distance and sphericity index, although greater in patients with severe regurgitation, did not significantly contribute to FMR severity.Degree of LV enlargement and dysfunction were not primary determinants of FMR severity, therefore local LV remodeling and mitral valve apparatus deformation are the strongest predictors of functional MR severity.Functional Mitral Regurgitation (FMR) defined as a regurgitation that seen with structurally normal valve leaflets. It occurs as a consequence of systolic LV dysfunction caused by ischemic or nonischemic cardiomyopathy. Functional MR occurs in roughly 20–25% of patients following MI and 50% of those with CHF [1,2]. Any degree of FMR in patients with LV dysfunction conveys adverse prognosis, [2-8], with a graded relationship between severity of regurgitation and
Analysis of the Magnetic Flux Density, the Magnetic Force and the Torque in a 3D Brushless DC Motor  [PDF]
Majid Pakdel
Journal of Electromagnetic Analysis and Applications (JEMAA) , 2009, DOI: 10.4236/jemaa.2009.11001
Abstract: As permanent magnet motors and generators produce torque, vibration occurs through the small air gap due to the alternating magnetic forces created by the rotating permanent magnets and the current switching of the coils. The magnetic force can be calculated from the flux density by finite element methods and the Maxwell stress tensor in cy-lindrical coordinates. In this paper the magnetic flux density, the magnetic force and the torque of a real three dimen-sional brushless DC motor are simulated using Maxwell 3 D V 11.1.
Numerical Study of Fluid Flow over Bundle Tubes  [PDF]
Majid Almas
Journal of Electronics Cooling and Thermal Control (JECTC) , 2016, DOI: 10.4236/jectc.2016.63010
Abstract: In this paper, a bank of tubes containing a flowing fluid which is immersed in a cross flow second medium of fluid with different temperature has been studied numerically using computational fluid dynamics. Laminar steady flow with a low Reynolds number has been studied in this work. Inlet mass flow rate and the bulk temperature are known and numerical method has been implemented to study the convective heat transfer to investigate the temperature and flow fields. Effects of different inlet bulk temperatures and mass flow rates have been investigated on temperature and pressure variations.
Clinical and Echocardiographic Evaluation of Regional Systolic Function Detected by Tissue Doppler Imaging in Hypertrophic Cardiomyopathy
A Sadeghpour,M Kiavar,N Behzadnia,Sh Maddadi
Iranian Cardiovascular Research Journal , 2009,
Abstract: Background: Hypertrophic cardiomyopathy (HCM) is the most common type of the genetic cardiovasculardiseases. Regarding to tremendous heterogeneity in the phenotypic expression of HCM, which is generally unrelatedto genotype, we aimed to study, clinical and echocardiographic parameters such as Tissue Doppler Imaging(TDI) in various subtypes of HCM patients and evaluate the influence of race and gender in Iranian patients.Methods: Patients with HCM underwent a complete clinical and echocardiographic study including TDI toassess regional systolic contraction( in the 12 segments ) and early diastolic annular velocity (Em) from theseptal mitral annulus.Results: The study comprised 41 patients (20 women, mean age = 41 ± 15 years) with mean LVEF 55%±4.8%and mean maximal septal thickness 2.07cm. Considering LVOT gradient>30mmHg, hypertrophic obstructivecardiomyopathy (HOCM) was found in 18 (45%). Asymmetric septal hypertrophy (ASH) existed in 27 patients(67%), systolic anterior motion of anterior mitral leaflet (SAM) in 25 persons (64%). Nineteen patients (46.3%)were included in NYHA function class (FC) II and 6 (14.7%) in FC III or higher. We found syncope in 10(24.4%), chest pain in 4 (9.8%), atrial fibrilation in 14.6 % and ventricular arrhythmias in (17.1%) of patients.History of ICD was seen in 7 (17.1%) and PPM in 9 cases. Mean E’ velocity was 5.44± 1.65 cm/sec and S velocity5.70± 1.49 cm/sec with significant lower S velocity and E’ in syncope patients. Overall, HOCM patients hadgrade II diastolic dysfunction with E/é >15(17.54±7.46). Majority (25) of cases (61%) were categorized in typeIII of HCM. RV involvement was observed in 11 patients (28.2%).No significant differences existed betweenprevalence of syncope and dysrhythmia among HCM and HOCM patients.Conclusion: In our study, we found lower detection of latent HOCM, compared to other studies, suggestive ofinadequate use of appropriate provocative maneuvers such as exercise stress echocardiography and amyl nitrate.We detected remarkably lower S velocity (5.70± 1.49 cm/sec) and E’ velocity (5.44± 1.65 cm/sec) in HCM patientscompared to normal subjects, with more significant reductions in patients with syncope.
Non-Invasive Assessment of Left Ventricular End-Diastolic Pressure in Patients with Chronic Aortic Regurgitation, Comparison of the Sensitivity and Specificity of CW Doppler Echocardiography with Angiography
M Esmaeilzadeh,M Hamidzad,M Kiavar,H Bakhshandeh
Iranian Cardiovascular Research Journal , 2009,
Abstract: Background: Left ventricular end diastolic pressure could be estimated collectively using various measures of mitral valve and pulmonary venous flow velocities. In patients with aortic regurgitation, the AR velocity reflects the diastolic pressure difference between the aorta and the left ventricle. We sought to predict the left ventricular end diastolic pressure by a new Doppler index as aortic regurgitation peak early to late diastolic pressure gradient ratio.Patients and Methods: Fifty three patients with at least moderate aortic regurgitation were enrolled in this study. Physical examination, electrocardiography and echocardiography were performed one day before cardiac catheterization. The severity of AR was graded according to the recommendations of American society for echocardiography. The pressure half time, aortic regurgitation early diastolic velocity , aortic regurgitation early diastolic pressure gradient , aortic regurgitation end diastolic velocity, aortic regurgitation end diastolic pressure gradient, and early diastolic to end diastolic pressure gradient ratio of averaged three beats were measured and recorded. The results from cardiac catheterization and echocardiography were compared.Result: The early diastolic to end diastolic pressure gradient ratio was very accurate (80%) for determining the left ventricular end diastolic pressure (P =0.01). An early diastolic to end diastolic pressure gradient ratio of 1.5 has a sensitivity of 96% and a specificity of 32% for left ventricular end diastolic pressure ≤12 mmHg. The best cutoff value of early diastolic to end diastolic pressure gradient ratio for the prediction of left ventricular end diastolic pressure >12 mmHg was higher than 2.0, with a sensitivity of 71% and specificity of 96% We found no significant correlation between the left ventricular end diastolic pressure with either left ventricular ejection fraction or aortic regurgitation severity in cardiac catheterization (P =0.5).Conclusion: Doppler echocardiography is a viable alternative of cardiac catheterization for determination of the left ventricular end diastolic pressure. The early diastolic to end diastolic pressure gradient ratio is a simple, easy and new method for assessment of the LVEDP in patients with severe chronic aortic regurgitation.
Myocardial Viability Assessment: Comparison between Resting Two Dimensional Visual Assessment of Dobutamine Stress Echocardiography and Strain Rate Imaging
A Sadeghpour,M Kiavar,M Hajiaghaie,M Esmaielzadeh
Iranian Cardiovascular Research Journal , 2008,
Abstract: Background: Patients with ischemic left ventricular dysfunction are increasingly referred for the assessmentof myocardial viability. The issue of identifying dysfunctional but viable myocardium has crucial clinical importance,since revascularization increases survival only in patients with viable myocardial tissue. The aim ofthis study was to compare resting two-dimensional visual assessment of myocardial viability with dobutaminestress echocardiography and strain rate imaging.Patients and Methods: In this cross-sectional study , thirty-two consecutive patients (age: 55.3 ± 22.7, 4 females)with ischemic left ventricular dysfunction were referred for myocardial viability assessment. Viabilitywas evaluated using resting two-dimensional echocardiograms, dobutamine stress echocardiography and strainrate imaging. Viability was defined by the absence of brightness and thinning (<6 mm thickness) in akineticsegments, improvement by at least one grade or a biphasic response during dobutamine stress echocardiographyor an increase in the peak systolic strain rate (more than –0.23 1/s).Results: A total of 254 segments were studied. Seventy- nine segments by dobutamine stress echocardiography,70 segments by two-dimensional visual assessment, and 63 segments by strain rate were classified as non-viable(P< 0.001). There was an almost perfect agreement among these diagnostic methods.Conclusions: Two-dimensional visual assessment with measurement of wall thickness is simple and practicalmethods for viability assessment, with almost perfect agreement with dobutamine stress echocardiography andstrain rate imaging.
Correlation of Right Ventricular dP/dt with Functional Capacity and RV Function in Patients with Mitral Stenosis
Anita Sadeghpour,H Harati, M Kiavar,M Esmaeizadeh,M Maleki
Iranian Cardiovascular Research Journal , 2008,
Abstract: Background: Evaluation of right ventricular (RV) contractility and systolic function in patients with right sided heart disease is an essential component of clinical management. The aim of this study was to assess RV systolic function by qualitative and quantitative methods and compare it to rate of ventricular pressure change during the isovolumic contraction period (dP/dt) as RV contractility index in patients with rheumatic mitral stenosis.Patients and Methods: In 56 consecutive patients with moderate to severe mitral stenosis, RV systolic function, RV dP/dt and dP/dt/Pmax, were calculated and compared. Results: There was significant correlation between RV dP/dt and RV function (P<0.001) and between RV dP/dt and New York Heart Association (NYHA) functional capacity (P<.001). The mean of dP/dt was decreased with increasing severity of RV dysfunction (mean dP/dt was 648±159 for normal RV function, 592± 126 for mild RV dysfunction, 319±146 for moderate RV dysfunction and 166±150 for severe RV dysfunction) Severity of tricuspid regurgitation and pulmonary hypertension had no significant effect on RV dP/dt and RV function.RV dP/dt/Pmax had also significant relationship with RV function and functional capacity (P <0.001). Conclusion: Measurements of dP/dt and dP/dt/Pmax, are practical methods for estimating RV contractility and results have a good correlation with RV systolic function and functional capacity.
Analytical Solution of Two Extended Model Equations for Shallow Water Waves by He’s Variational Iteration Method  [PDF]
Mehdi Safari, Majid Safari
American Journal of Computational Mathematics (AJCM) , 2011, DOI: 10.4236/ajcm.2011.14027
Abstract: In this paper, we consider two extended model equations for shallow water waves. We use He’s variational iteration method (VIM) to solve them. It is proved that this method is a very good tool for shallow water wave equations and the obtained solutions are shown graphically.
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