期刊文献+
共找到40篇文章
< 1 2 >
每页显示 20 50 100
Double-chambered left ventricle with a thrombus in an asymptomatic patient:A case report
1
作者 Narae Kim In-Ho Yang +1 位作者 Hui-Jeong Hwang Il-Suk Sohn 《World Journal of Clinical Cases》 SCIE 2024年第2期460-465,共6页
BACKGROUND Double-chambered left ventricle(DCLV)is an extremely rare congenital disease in which the left ventricle(LV)is divided by abnormal muscle tissue.Due to its rarity,there is a lack of data on the disease,incl... BACKGROUND Double-chambered left ventricle(DCLV)is an extremely rare congenital disease in which the left ventricle(LV)is divided by abnormal muscle tissue.Due to its rarity,there is a lack of data on the disease,including its diagnosis,treatment,and prognosis.Accordingly,we report a case in which DCLV was diagnosed and followed up.CASE SUMMARY A 45-year-old man presented to our hospital due to abnormal findings on an electrocardiogram recorded during a health check.He had no specific cardiac symptoms,comorbidities or relevant past medical history.Echocardiography revealed that the LV was divided into two by muscle fibers.There were no findings of ischemia on coronary angiography and coronary computed tomography angiography performed to exclude differential diagnoses.After comprehensive analysis of the images,DCLV was diagnosed.As it seemed to be asymptomatic DCLV,we decided the patient was to be observed without administering any medication.However,follow-up echocardiography revealed a thrombus in the accessory chamber(AC).Anticoagulant medication was initiated,the thrombus resolved,and the patient is currently undergoing follow-up without any specific symptoms.CONCLUSION Asymptomatic,uncomplicated DCLV was diagnosed through multimodal imaging;however,a thrombus in the AC occurred during the follow-up.The findings highlight that multimodal imaging is essential in diagnosing DCLV,and that anticoagulation is important in its management. 展开更多
关键词 Double-chambered left ventricle Congenital heart disease left ventricular aneurysm Echocardiography Coronary computed tomography angiography Contrast echocardiography Case report
下载PDF
An Interpretable CNN for the Segmentation of the Left Ventricle in Cardiac MRI by Real-Time Visualization 被引量:1
2
作者 Jun Liu Geng Yuan +2 位作者 Changdi Yang Houbing Song Liang Luo 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第5期1571-1587,共17页
The interpretability of deep learning models has emerged as a compelling area in artificial intelligence research.The safety criteria for medical imaging are highly stringent,and models are required for an explanation... The interpretability of deep learning models has emerged as a compelling area in artificial intelligence research.The safety criteria for medical imaging are highly stringent,and models are required for an explanation.However,existing convolutional neural network solutions for left ventricular segmentation are viewed in terms of inputs and outputs.Thus,the interpretability of CNNs has come into the spotlight.Since medical imaging data are limited,many methods to fine-tune medical imaging models that are popular in transfer models have been built using massive public Image Net datasets by the transfer learning method.Unfortunately,this generates many unreliable parameters and makes it difficult to generate plausible explanations from these models.In this study,we trained from scratch rather than relying on transfer learning,creating a novel interpretable approach for autonomously segmenting the left ventricle with a cardiac MRI.Our enhanced GPU training system implemented interpretable global average pooling for graphics using deep learning.The deep learning tasks were simplified.Simplification included data management,neural network architecture,and training.Our system monitored and analyzed the gradient changes of different layers with dynamic visualizations in real-time and selected the optimal deployment model.Our results demonstrated that the proposed method was feasible and efficient:the Dice coefficient reached 94.48%,and the accuracy reached 99.7%.It was found that no current transfer learning models could perform comparably to the ImageNet transfer learning architectures.This model is lightweight and more convenient to deploy on mobile devices than transfer learning models. 展开更多
关键词 Interpretable graphics training VISUALIZATION image segmentation left ventricle CNNS global average pooling
下载PDF
Value of clinical applications of differential pressure and relative pressure imaging in the left ventricle
3
作者 An-Sheng Zheng Hong-Xia Yu 《World Journal of Clinical Cases》 SCIE 2023年第17期3967-3975,共9页
Regional pressure differences between sites within the left ventricular cavity have long been identified,and the potential clinical value of diastolic and systolic intraventricular pressure differences(IVPDs)is of inc... Regional pressure differences between sites within the left ventricular cavity have long been identified,and the potential clinical value of diastolic and systolic intraventricular pressure differences(IVPDs)is of increasing interest.This study concluded that the IVPD plays an important role in ventricular filling and emptying and is a reliable indicator of ventricular relaxation,elastic recoil,diastolic pumping,and effective left ventricular filling.Relative pressure imaging,as a novel and potentially clinically applicable measure of left IVPDs,enables early and more comprehensive identification of the temporal and spatial characteristics of IVPD.In the future,as research related to relative pressure imaging continues,this measurement method has the possibility to become more refined and serve as an additional clinical aid that can replace the gold standard cardiac catheterization technique for the diagnosis of diastolic dysfunction. 展开更多
关键词 Cardiac imaging techniques ECHOCARDIOGRAPHY Ventricular dysfunction left ventricle Cardiovascular physiological phenomena HEMODYNAMICS Ventricular pressure
下载PDF
Inadvertent Lead Malposition in the Left Ventricle during Permanent Ventricular Pacing about One Case
4
作者 Khadidiatou Dia Waly Niang Mboup +5 位作者 Serigne Cheikh Tidiane Ndao Mame Madjiguene Ka Rabab Yassine Djibril Marie Ba Demba Ware Balde Mouhamed Cherif Mboup 《World Journal of Cardiovascular Diseases》 2023年第11期756-763,共8页
Inadvertent Lead Malposition in Left Ventricle is a rare and underdiagnosed incident, which may occur during implantation of cardiac electronic devices and may remain asymptomatic. We reported the case of a 71-year-ol... Inadvertent Lead Malposition in Left Ventricle is a rare and underdiagnosed incident, which may occur during implantation of cardiac electronic devices and may remain asymptomatic. We reported the case of a 71-year-old man who was implanted with a ventricular single-chamber pacemaker for a slow atrial fibrillation with syncope and whose routine transthoracic echocardiography 23 months after implantation displayed a malposition of the pacemaker lead into the Left Ventricle through a patent foramen oval. The patient was asymptomatic. The electrocardiogram showed right bundle branch block QRS-paced morphology with a positive QRS pattern in V1, a median paced QRS axis on the frontal plane at -120°, a Precordial transition on V5. At the lateral Chest X-ray the lead curved backwards to the spine. Given the age of this old patient who already received oral anticoagulant for Atrial Fibrillation and the Lead malposition discovered 23 months after pacemaker’s implantation, we decided to maintain the lead in LV and continue anticoagulation. 展开更多
关键词 Lead Malposition left ventricle Lead Right Bundle Branch Block Ventricu-lar Pacing Transthoracic Echocardiography
下载PDF
Left to Right Extracardial Shunt to Control Hemorrhage of Ascending Aorta and Left Ventricle: A Report of 3 Cases 被引量:4
5
作者 刘成硅 杨辰垣 +3 位作者 张凯伦 孙宗权 肖诗亮 蓝鸿钧 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 1998年第3期177-179,共3页
Presented in this paper are 3 cases of hemorrhage of ascending aorta and left ventricle after open heart surgery treated by extracardial bypass in our hospital from Oct. 1994 to Dec. 1995. Remained aneurysmal wall enc... Presented in this paper are 3 cases of hemorrhage of ascending aorta and left ventricle after open heart surgery treated by extracardial bypass in our hospital from Oct. 1994 to Dec. 1995. Remained aneurysmal wall enclosing conduit graft was used as a sac bypassed to right atrium to form a extracardial left-toright shunt in order to control bleeding and the results turned out to be satisfactory. The bypass and hemodynamically ignorable shunt can close spontaneously without complications with recovery of coagulation system. The technique may find wide application in clinical practice. 展开更多
关键词 left-to-right extracardial shunt HEMORRHAGE ascending aorta left ventricle
下载PDF
NONLINEAR DYNAMICS MODFLING OF MECHANICAL PERIODICITY OF END DIASTOLIC VOLUME OF LEFT VENTRICLE 被引量:1
6
作者 XU Shi-xiong(许世雄) +1 位作者 MAO Xiao-chun(毛晓春) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第10期1183-1191,共9页
The cardiovascular system with a lumped parameter model is treated, in which the Starling model is used to simulate left ventricle and the four-element Burattini & Gnudi model is used in the description of... The cardiovascular system with a lumped parameter model is treated, in which the Starling model is used to simulate left ventricle and the four-element Burattini & Gnudi model is used in the description of arterial system. Moreover, the feedback action of arterial pressure on cardiac cycle is taken into account. The phenomenon of mechanical periodicity (MP) of end diastolic volume (EDV) of left ventricle is successfully simulated by solving a series of one-dimensional discrete nonlinear dynamical equations. The effects of cardiovascular parameters on MP is also discussed. 展开更多
关键词 left ventricle end diastolic volume mechanical periodicity nonlinear dynamics
下载PDF
A NUMERICAL MODEL OF LEFT VENTRICLE AND AORTIC VALVE FUNCTION OF ITS AFTERLOAD(Ⅰ) 被引量:1
7
作者 柳兆荣 尹永义 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第2期153-162,共10页
Due to the study of the function of heart and aoritic valve, we set up a physicalmodel of left ventricle, aortic valve and afterload and derive theoretical equation of each part from the model. Then we calculate the h... Due to the study of the function of heart and aoritic valve, we set up a physicalmodel of left ventricle, aortic valve and afterload and derive theoretical equation of each part from the model. Then we calculate the hasic equations within phystology and impair parameters. Bwsed on this, we will discus fully in the next paper the effectofleyt ventricular afterloadon valve opining, ejection and valve Jumction .etc 展开更多
关键词 A NUMERICAL MODEL OF left ventricle AND AORTIC VALVE FUNCTION OF ITS AFTERLOAD
下载PDF
Effect of gestational protein restriction on left ventricle hypertrophy and heart angiotensin II signaling pathway in adult offspring rats 被引量:1
8
作者 Renan Brisolla da Silva Flavia Fernandes Mesquita +3 位作者 Marilia Andreo Heloisa Balan Assalin Jose Antonio Rocha Gontijo Patricia Aline Boer 《Health》 2013年第4期78-84,共7页
Maternal protein restriction may be a risk factor for cardiovascular disorders in adulthood. The RAS (renin-angiotensin-system) plays a pivotal role in cardiac remodeling. Components of the RAS, including angiotensin ... Maternal protein restriction may be a risk factor for cardiovascular disorders in adulthood. The RAS (renin-angiotensin-system) plays a pivotal role in cardiac remodeling. Components of the RAS, including angiotensin II (AngII) and its receptors type 1 (AT1R) and 2 (AT2R) are expressed in the heart. This study investigates whether gestational protein restriction alters the expression and localization of AT1R and AT2R and RAS signaling pathway proteins in parallel with left ventricle hypertrophy and systemic hypertension in male offspring. Dams were kept on normal (NP, 17% protein) or low (LP, 6% protein) protein diet during pregnancy. Systolic blood pressure (SBP) of male offspring was measured from the 8th to 16th week and left ventricles of 16-wk-old rats were processed for histology, morphometric, immunoblotting and immunohistochemistry. LP offspring showed a significant reduction in birth body weight and SBP increased significantly from the 8th week. Left ventricle mass and cardiomyocytes area were also significantly higher in LP animals. Widespread perivascular fibrosis was not detected in the heart tissue. Analysis by immunoblotting and immunohistochemistry demonstrated a significant enhance in cardiomyocyte expression of AT1R and ERK1 in LP offspring. Expression of PI3K in LP was significantly reduced in cardiomyocytes and in the intramural coronary wall, while AT2R expression was unchanged in the NP group. We also found reduced LP expression of JAK2 and STAT3. In conclusion, our data also suggest that changes in the RAS may play a role in the ventricular growth through upregulation of the AT1-mediated ERK1/2 response, despite unchanged AT2R expression. 展开更多
关键词 Low Birth Weight Arterial Hypertension Fetal Programming Protein Restriction Angiotensin II left ventricle Hypertrophy Cardiovascular Disease
下载PDF
Clinical Study on Preventing and Treating Left Ventricle Remodeling after Acute Myocardial Infarction with Integrative Chinese and Western Medicine
9
作者 唐耀平 刘鹰 梁萍 《Chinese Journal of Integrated Traditional and Western Medicine》 2004年第1期25-28,共4页
Objective: To explore the clinical efficacy of Xuefu Zhuyu (血府逐瘀, XFZY) oral liquid combined with western medicine (WM) in reversing left ventricle remodeling (LVR) after acute myocardial infarction (AMI) in patie... Objective: To explore the clinical efficacy of Xuefu Zhuyu (血府逐瘀, XFZY) oral liquid combined with western medicine (WM) in reversing left ventricle remodeling (LVR) after acute myocardial infarction (AMI) in patients and its therapeutic mechanism. Methods: Sixty patients conforming to criteria were divided into the treated group and WM control group with randomly stratified method. Thirty cases were assigned to each group, they were given XFZY + WM + general treatment and WM + general treatment respectively. Color Doppler ultrasonography was used to study the changes of LVR before and after treatment. Results: In both groups, before and after treatment the P value of such parameters as the changes of their left diastolic volume (LDV), left systolic volume (LSV), left ventricle ejection fraction (EF) was <0.05, suggesting that the difference of various parameters was significantly different; but when compared with the results of the 12th week after medications, the change of LDV, LSV, EF showed that the LDV, LSV of the treated group were lower than that of the control group, the EF of the treated group was higher than that of the control group, and the P value of various groups was all <0.05, suggesting that the different data of various groups showed significant difference. Conclusion: Conventional WM treatment and XFZY combined with WM could both, in treating AMI, effectively reverse the patients' LVR; yet the use of integrative Chinese and western medicine on reversing patients LVR showed even better results than that of simple WM treatment. 展开更多
关键词 Xuefu Zhuyu oral liquid left ventricle remodeling ULTRASONOGRAPHY
下载PDF
Diagnostic Accuracy of Strain Imaging of the Left Ventricle in Detection of Obstructive Coronary Artery Disease
10
作者 Mohamed Fahmy Elnoamany Waleed Abdou Ibrahim Ahmed Mahmoud Hamza 《World Journal of Cardiovascular Diseases》 2020年第8期572-586,共15页
<strong>Background: </strong><span style="font-family:Verdana;">Speckle tracking echocardiography using average global strain and strain</span><b><span style="font-famil... <strong>Background: </strong><span style="font-family:Verdana;">Speckle tracking echocardiography using average global strain and strain</span><b><span style="font-family:Verdana;"> </span></b><span style="font-family:Verdana;">rate (SR) parameters for early detection of high risk patients with coronary artery disease (CAD) has gained a substantial clinical interest. </span><b><span style="font-family:Verdana;">Objective:</span></b><span style="font-family:Verdana;"> Assessment of the diagnostic accuracy of strain imaging of the left ventricle in detection of obstructive coronary artery disease. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> One hundred patients were enrolled</span><span style="font-family:Verdana;">. </span><span style="font-family:Verdana;">They were divided into 3 groups</span><span style="font-family:Verdana;">: </span><span style="font-family:Verdana;">Group I (n = 40 patients) presented with ST segment elevation myocardial infarction (STEMI), Group II (n = 40 patients) presented with non-ST segment elevation myocardial infarction (NSTEMI) or unstable angina (UA) and Group</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">III </span><span style="font-family:Verdana;">(n = 20 patients) with normal coronary angiography served as a control group. All patients were subjected to 2D speckle tracking echocardiography (2D STE) to assess LV longitudinal strain and strain rate (SR). Sensitivity, specificity and diagnostic accuracy of 2D STE in prediction of CAD and its severity using Gensini score were assessed. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> The mean age for Group I, II and III was 52.20 ± 11.83, 51.97 ± 14.53 and 52.75 ± 10.75 respectively. LV average global systolic strain (AGS) was significantly lower in group I and II when compared to group III. AGS and average global systolic SR showed significant direct correlation with Gensini score. The diagnostic accuracy of 2D STE in prediction of significant LAD stenosis was 92.5%, and it was 89.5% in prediction of 3 vessels CAD. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> Strain imaging using 2D STE can predict the territory and severity of CAD with high diagnostic accuracy</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">and can be used as a simple noninvasive diagnostic tool to identify high risk CAD patients.</span> 展开更多
关键词 Coronary Artery Disease left ventricle Strain Imaging
下载PDF
The Effects of Axial-Flow Pump in Supporting of Regional Ischemic Left Ventricle: A Simulation Study
11
作者 Bing Zhao and Jing Bai(Department of Electrical Engineering, The School of Life Science and Engineering,Tsinghua University, Beijing 100084, China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1999年第3期46-47,共2页
关键词 Simulation A Simulation Study The Effects of Axial-Flow Pump in Supporting of Regional Ischemic left ventricle FLOW
下载PDF
Fluid-structure interaction simulation of pathological mitral valve dynamics in a coupled mitral valve-left ventricle model
12
作者 Li Cai Tong Zhao +2 位作者 Yongheng Wang Xiaoyu Luo Hao Gao 《Intelligent Medicine》 CSCD 2023年第2期104-114,共11页
Background Understanding the interaction between the mitral valve(MV)and the left ventricle(LV)is very important in assessing cardiac pump function,especially when the MV is dysfunctional.Such dysfunction is a major m... Background Understanding the interaction between the mitral valve(MV)and the left ventricle(LV)is very important in assessing cardiac pump function,especially when the MV is dysfunctional.Such dysfunction is a major medical problem owing to the essential role of the MV in cardiac pump function.Computational modelling can provide new approaches to gain insight into the functions of the MV and LV.Methods In this study,a previously developed LV-MV model was used to study cardiac dynamics of MV leaflets under normal and pathological conditions,including hypertrophic cardiomyopathy(HOCM)and calcification of the valve.The coupled LV-MV model was implemented using a hybrid immersed boundary/finite element method to enable assessment of MV haemodynamic performance.Constitutive parameters of the HOCM and calcified valves were inversely determined from published experimental data.The LV compensation mechanism was further studied in the case of the calcified MV.Results Our results showed that MV dynamics and LV pump function could be greatly affected by MV pathology.For example,the HOCM case showed bulged MV leaflets at the systole owing to low stiffness,and the calcified MV was associated with impaired diastolic filling and much-reduced stroke volume.We further demonstrated that either increasing the LV filling pressure or increasing myocardial contractility could enable a calcified valve to achieve near-normal pump function.Conclusion The modelling approach developed in this study may deepen our understanding of the interactions between the MV and the LV and help in risk stratification of heart valve disease and in silico treatment planning by exploring intrinsic compensation mechanisms. 展开更多
关键词 Mitral valve left ventricle Valve disease Hybrid immersed boundary/finite element method CALCIFICATION Hypertrophic cardiomyopathy
原文传递
Prenatal Diagnosis of an Apically Located Congenital Left Ventricular Aneurysm: A Rare Case
13
作者 Yücel Kaya And Yavuz +3 位作者 Hasan Berkan Sayal Büşra Tsakir Gökalp Kabacaoğlu Kadriye NilayÖzcan 《Congenital Heart Disease》 SCIE 2024年第1期123-129,共7页
Congenital ventricular aneurysm is a very rare cardiac anomaly.A diagnosis can be made during the prenatal period using fetal echocardiography.This study presents a very rare apically located left ventricular aneurysm... Congenital ventricular aneurysm is a very rare cardiac anomaly.A diagnosis can be made during the prenatal period using fetal echocardiography.This study presents a very rare apically located left ventricular aneurysm case,and the relevant literature was reviewed and discussed.In this case,a 35-year-old,gravida 2,parity 1 preg-nant woman at 24 weeks of gestation,displayed a wide aneurysmal image in the left ventricular apical wall on fetal echocardiography.There was a 1.79 mm muscular ventricular septal defect at the apical region of the interven-tricular septum.In the course of the color Doppler ultrasonography examination,an aberrantfibrous band within the left ventricle and consequent turbulentflow during systole were observed.The baby,born via cesarean section at 37 weeks of gestation,is now in its postnatal seventh month.However,during echocardiographic follow-ups,changes have been observed,including mild to moderate mitral insufficiency and a decrease in systolic function.Despite thesefindings,the clinical condition remains asymptomatic.It is of great importance to use a multidis-ciplinary approach in managing these rare cases that could lead to potential adverse outcomes during the antena-tal or postnatal periods. 展开更多
关键词 Heart aneurysm prenatal diagnosis ECHOCARDIOGRAPHY congenital heart defects left ventricle
下载PDF
Seg-CapNet:A Capsule-Based Neural Network for the Segmentation of Left Ventricle from Cardiac Magnetic Resonance Imaging 被引量:3
14
作者 Yang-Jie Cao Shuang Wu +4 位作者 Chang Liu Nan Lin Yuan Wang Cong Yang Jie Li 《Journal of Computer Science & Technology》 SCIE EI CSCD 2021年第2期323-333,共11页
Deep neural networks(DNNs)have been extensively studied in medical image segmentation.However,existing DNNs often need to train shape models for each object to be segmented,which may yield results that violate cardiac... Deep neural networks(DNNs)have been extensively studied in medical image segmentation.However,existing DNNs often need to train shape models for each object to be segmented,which may yield results that violate cardiac anatomical structure when segmenting cardiac magnetic resonance imaging(MRI).In this paper,we propose a capsulebased neural network,named Seg-CapNet,to model multiple regions simultaneously within a single training process.The Seg-CapNet model consists of the encoder and the decoder.The encoder transforms the input image into feature vectors that represent objects to be segmented by convolutional layers,capsule layers,and fully-connected layers.And the decoder transforms the feature vectors into segmentation masks by up-sampling.Feature maps of each down-sampling layer in the encoder are connected to the corresponding up-sampling layers,which are conducive to the backpropagation of the model.The output vectors of Seg-CapNet contain low-level image features such as grayscale and texture,as well as semantic features including the position and size of the objects,which is beneficial for improving the segmentation accuracy.The proposed model is validated on the open dataset of the Automated Cardiac Diagnosis Challenge 2017(ACDC 2017)and the Sunnybrook Cardiac Magnetic Resonance Imaging(MRI)segmentation challenge.Experimental results show that the mean Dice coefficient of Seg-CapNet is increased by 4.7%and the average Hausdorff distance is reduced by 22%.The proposed model also reduces the model parameters and improves the training speed while obtaining the accurate segmentation of multiple regions. 展开更多
关键词 capsule neural network image segmentation left ventricle segmentation cardiac magnetic resonance imaging
原文传递
Automated Segmentation of Left Ventricle Using Local and Global Intensity Based Active Contour and Dynamic Programming 被引量:2
15
作者 G.Dharanibai Anupama Chandrasekharan Zachariah C.Alex 《International Journal of Automation and computing》 EI CSCD 2018年第6期673-688,共16页
The aim of this work is to develop an improved region based active contour and dynamic programming based method for accurate segmentation of left ventricle (LV) from multi-slice cine short axis cardiac magnetic reso... The aim of this work is to develop an improved region based active contour and dynamic programming based method for accurate segmentation of left ventricle (LV) from multi-slice cine short axis cardiac magnetic resonance (MR) images. Intensity inhomogeneity and weak object boundaries present in MR images hinder the segmentation accuracy. The proposed active contour model driven by a local Gaussian distribution fitting (LGDF) energy and an auxiliary global intensity fitting energy improves the accuracy of endocardial boundary detection. The weightage of the global energy fitting term is dynamically adjusted using a spatially varying weight function. Dynamic programming scheme proposed for the segmentation of epicardium considers the myocardium probability map and a distance weighted edge map in the cost matrix. Radial distance weighted technique and conical geometry are employed for segmenting the basal slices with left ventricle outflow tract (LVOT) and most apical slices. The proposed method is validated on a public dataset comprising 45 subjects from medical image computing and computer assisted interventions (MICCAI) 2009 segmentation challenge. The average percentage of good endocardial and epicardial contours detected is about 99%, average perpendicular distance of the detected good contours from the manual reference contours is 1.95 mm, and the dice similarity coefficient between the detected contours and the reference contours is 0.91. Correlation coefficient and the coefficient of determination between the ejection fraction measurements from manual segmentation and the automated method are respectively 0.9781 and 0.9567, for LV mass these values are 0.9249 and 0.8554. Statistical analysis of the results reveals a good agreement between the clinical parameters determined manually and those estimated using the automated method. 展开更多
关键词 Cardiovascular magnetic resonance left ventricle ENDOCARDIUM EPICARDIUM MYOCARDIUM segmentation active contour dynamic programming.
原文传递
Detection of Left Ventricular Cavity from Cardiac MRI Images Using Faster R-CNN
16
作者 Zakarya Farea Shaaf Muhammad Mahadi Abdul Jamil +3 位作者 Radzi Ambar Ahmed Abdu Alattab Anwar Ali Yahya Yousef Asiri 《Computers, Materials & Continua》 SCIE EI 2023年第1期1819-1835,共17页
The automatic localization of the left ventricle(LV)in short-axis magnetic resonance(MR)images is a required step to process cardiac images using convolutional neural networks for the extraction of a region of interes... The automatic localization of the left ventricle(LV)in short-axis magnetic resonance(MR)images is a required step to process cardiac images using convolutional neural networks for the extraction of a region of interest(ROI).The precise extraction of the LV’s ROI from cardiac MRI images is crucial for detecting heart disorders via cardiac segmentation or registration.Nevertheless,this task appears to be intricate due to the diversities in the size and shape of the LV and the scattering of surrounding tissues across different slices.Thus,this study proposed a region-based convolutional network(Faster R-CNN)for the LV localization from short-axis cardiac MRI images using a region proposal network(RPN)integrated with deep feature classification and regression.Themodel was trained using images with corresponding bounding boxes(labels)around the LV,and various experiments were applied to select the appropriate layers and set the suitable hyper-parameters.The experimental findings showthat the proposed modelwas adequate,with accuracy,precision,recall,and F1 score values of 0.91,0.94,0.95,and 0.95,respectively.This model also allows the cropping of the detected area of LV,which is vital in reducing the computational cost and time during segmentation and classification procedures.Therefore,itwould be an ideal model and clinically applicable for diagnosing cardiac diseases. 展开更多
关键词 Cardiac short-axis MRI images automatic left ventricle localization deep learning models faster R-CNN
下载PDF
Isolated left ventricular apical hypoplasia:Systematic review and analysis of the 37 cases reported so far
17
作者 Pier Paolo Bassareo Sophie Duignan +3 位作者 Adam James Esme Dunne Colin J McMahon Kevin P Walsh 《World Journal of Clinical Cases》 SCIE 2023年第23期5494-5503,共10页
BACKGROUND Isolated left ventricular apical hypoplasia(ILVAH),also known as truncated left ventricle(LV),is a very unusual cardiomyopathy.It is characterised by a truncated,spherical,and non-apex forming LV.The true a... BACKGROUND Isolated left ventricular apical hypoplasia(ILVAH),also known as truncated left ventricle(LV),is a very unusual cardiomyopathy.It is characterised by a truncated,spherical,and non-apex forming LV.The true apex is occupied by the right ventricle.Due to the rarity of the disease,just a few case reports and limited case series have been published in the field.AIM To analysing the so far 37 reported ILVAH cases worldwide.METHODS The electronic databases PubMed and Scopus were investigated from their establishment up to December 13,2022.RESULTS The majority of cases reported occurred in males(52.7%).Mean age at diagnosis was 26.1±19.6 years.More than a third of the patients were asymptomatic(35.1%).The most usual clinical presentation was breathlessness(40.5%).The most commonly detected electrocardiogram changes were T wave abnormalities(29.7%)and right axis deviation with poor R wave progression(24.3%).Atrial fibrillation/flutter was detected in 24.3%.Echocardiography was performed in 97.3%of cases and cardiac MRI in 91.9%of cases.Ejection fraction was reduced in more than a half of patients(56.7%).An associated congenital heart disease was found in 16.2%.Heart failure therapy was administered in 35.1%of patients.The outcome was favorable in the vast majority of patients,with just one death.CONCLUSION ILVAH is a multifaceted entity with a so far unpredictable course,ranging from benign until the elderly to sudden death during adolescence. 展开更多
关键词 Isolated left ventricular apical hypoplasia Truncated left ventricle ELECTROCARDIOGRAPHY Echocardiography Cardiac magnetic resonance imaging Heart failure
下载PDF
Left Ventricular Systolic Intraventricular Flow Field Assessment in Hyperthyroidism Patients Using Vector Flow Mapping 被引量:9
18
作者 周滨瑜 王静 +2 位作者 谢明星 刘曼薇 吕清 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2015年第4期574-578,共5页
Summary: Intraventricular hydrodynamics is considered an important component of cardiac function assessment. Vector flow mapping (VFM) is a novel flow visualization method to describe cardiac pathophysiological con... Summary: Intraventricular hydrodynamics is considered an important component of cardiac function assessment. Vector flow mapping (VFM) is a novel flow visualization method to describe cardiac pathophysiological condition. This study examined use of new VFM and flow field for assessment of left ventricular (LV) systolic hemodynamics in patients with simple hyperthyroidism (HT). Thirty-seven simple HT patients were enrolled as HT group, and 38 gender- and age-matched healthy volunteers as control group. VFM model was used to analyze LV flow field at LV apical long-axis view. The follow- ing flow parameters were measured, including peak systolic velocity (Vs), peak systolic flow (Fs), total systolic negative flow (SQ) in LV basal, middle and apical level, velocity gradient from the apex to the aortic valve (AV), and velocity according to half distance (V1/2). The velocity vector in the LV cavity, stream line and vortex distribution in the two groups were observed. The results showed that there were no significant differences in the conventional parameters such as left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD) and left atrium diameter (LAD) between HT group and control group (P〉0.05). Compared with the control group, a brighter flow and more vortexes were detected in HT group. Non-uniform distribution occurred in the LV flow field, and the stream lines were discontinuous in HT group. The values of Vs and Fs in three levels, SQ in middle and basal levels, AV and V1/2 were higher in HT group than in control group (P〈0.01). AV was positively correlated with serum free thyroxin (FT4) (r=0.48, P〈0.01). Stepwise multiple regression analysis showed that LVEDD, FT4, and body surface area (BSA) were the influence factors of △V. The unstable left ventricular sys- tolic hydrodynamics increased in a compensatory manner in simple PIT patients. The present study in- dicated that VFM may be used for early detection of abnormal ventricle contraction in clinical settings. 展开更多
关键词 HYPERTHYROIDISM vector flow mapping left ventricle HYDRODYNAMICS flow field
下载PDF
Evaluation of Left Ventricular Function by Three-Dimensional Speckle-Tracking Echocardiography in Patients with Chronic Kidney Failure 被引量:1
19
作者 Yu-bo WANG Hui HUANG +4 位作者 Shan LIN Mei-jia HAO Lu-jiao HE Kun LIU Xiao-jun BI 《Current Medical Science》 SCIE CAS 2022年第4期895-901,共7页
Objective:To establish a quantitative evaluation of the left ventricle's systolic function in patients with chronic kidney failure(CKF)by three-dimensional speckle-tracking echocardiography.Methods:Two-dimensional... Objective:To establish a quantitative evaluation of the left ventricle's systolic function in patients with chronic kidney failure(CKF)by three-dimensional speckle-tracking echocardiography.Methods:Two-dimensional and three-dimensional transthoracic echocardiography was performed on 30 patients with CKF.The ejection fraction,mass and global peak longitudinal strain,global circumferential strain,global area strain,and global radial strain of the left ventricle were calculated.Results:The ejection fraction,mass and global peak longitudinal strain(GLS),global circumferential strain(GCS),global area strain(GAS),and global radial strain(GRS)in the CKF group were significantly lower than those in the control group.Simultaneously,the GLS,GCS,GAS and GRS were well correlated with the ejection fraction.For patients with normal ejection fraction in the CKF group,the GLS,GCS,GAS and GRS were lower than those in the control group,while the left ventricular mass was significantly higher in CKF patients than in the control group.For patients with hypertension in the CKF group,ejection fraction,GLS,GCS,GAS and GRS calculated using three-dimensional echocardiography were significantly lower than those in patients with normal blood pressure;however,the myocardial mass was higher.Conclusions:The parameters(GLS,GCS,GAS and GRS)calculated using three-dimensional speckle-tracking software were lower in the CKF group.Simultaneously,the left ventricular mass was higher in CFK patients than in the control group,thus showing that the myocardial contraction function was impaired and that myocardial remodeling had occurred. 展开更多
关键词 three-dimensional speckle-tracking echocardiography left ventricle ejection fraction STRAIN chronic kidney failure
下载PDF
Apical Left Ventricular Hypertrophic Cardiomyopathy: A Case Report
20
作者 Ramachandran Muthiah 《Case Reports in Clinical Medicine》 2016年第9期308-329,共23页
Apical hypertrophic cardiomyopathy (apical HCM) is a rare variant of hypertrophic cardiomyopathy with a prevalence of 1% - 2% in Asian population and carries a benign prognosis. It is usually silent in early stages an... Apical hypertrophic cardiomyopathy (apical HCM) is a rare variant of hypertrophic cardiomyopathy with a prevalence of 1% - 2% in Asian population and carries a benign prognosis. It is usually silent in early stages and manifests in adults with a suspicion of typical ECG changes of giant T wave inversion in left precordial leads. Transthoracic echocardiography is the mainstay of non-invasive diagnosis and provides a heterogeneous appearance of its morphological features with a spade-shaped LV (left ventricular) cavity. Background of this case study describes the apical HCM in an asymptomatic male at the age of 54 years old and also predicts the mixed and mid-ventricular forms of left ventricular HCM at this region of Thoothukudi in India. 展开更多
关键词 Apical Hypertrophy left ventricle Spade-Shaped LV Cavity ECHOCARDIOGRAPHY Yamaguchi Syndrome Apical Ballooning Syndrome
下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部