3.The technical principle and clinical application of intravascular ultrasound elastogram.
Journal of Biomedical Engineering 2005;22(1):163-166
The development of intravascular ultrasound (IVUS) techniques makes it possible to analyze the sectional information of the arteries and plaques. However, it can not precisely provide the biomechanical characterization of atheromas. The IVUS elastogram demonstrates tissue elasticity via estimating the axial stress-strain information of artery walls. With the help of such method, unstable lesions can be distinguished, the rupture inclination can be predicted, and the components of plaques are able to be classified. Compared with IVUS, elastogram is more objective. The constructing procedure and relative techniques as well as the preliminary clinical application, are reviewed in this article. The limitation at present and the probable future research direction are also mentioned.
Arteries
;
diagnostic imaging
;
Carotid Arteries
;
diagnostic imaging
;
Coronary Vessels
;
diagnostic imaging
;
Elasticity Imaging Techniques
;
methods
;
Femoral Artery
;
diagnostic imaging
4.Progress of quantitative intravascular optical coherence tomography.
Journal of Biomedical Engineering 2020;37(2):358-364
Intravascular optical coherence tomography (IVOCT) has emerged as a high-resolution and minimal-invasive imaging technique that provides high-speed visualization of coronary arterial vessel walls and clearly displays the vessel lumen and lesions under the intima. However, morphological gray-scale images cannot provide enough information about the tissue components to accurately characterize the plaque tissues including calcified, fibrous, lipidic and mixed plaques. Quantitative IVOCT ( IVOCT) is necessary to provide the physiological contrast mechanisms and obtain the characteristic parameters of tissues with clinical diagnostic value. In this paper, the progress of IVOCT is reviewed. The current methods for quantitatively measuring optical, elastic and hemodynamic parameters of vessel wall and plaque tissues using IVOCT gray-scale images and raw backscattered signals are introduced and potential development is forecast.
Coronary Artery Disease
;
diagnostic imaging
;
Coronary Vessels
;
diagnostic imaging
;
Humans
;
Tomography, Optical Coherence
;
trends
5.Research progress on image-based calculation of coronary artery fractional flow reserve.
Journal of Biomedical Engineering 2023;40(1):171-179
Coronary artery fractional flow reserve (FFR) is a critical physiological indicator for assessment of impaired blood flow caused by coronary artery stenosis. The wire-based invasive measurement of blood flow pressure gradient across stenosis is the gold standard for clinical measurement of FFR. However, it has the risk of vascular injury and requires the use of vasodilators, increasing the time and overall cost of interventional examination. Coronary imaging is playing an important role in clinical diagnosis of stenotic lesions, evaluation of severity of lesions, and planning of therapies. In recent years, the computation of FFR based on the physiological information of blood flow obtained from routinely collected coronary image data has become a research focus in this field. This technique reduces the cost of physiological assessment of coronary lesions and the use of pressure wires. It is beneficial to strengthen the physiological guidance in interventional therapy. In order to better understand this emerging technique, this paper highlights its implementation principle and diagnostic performance, analyzes practical problems and current challenges in clinical applications, and discusses possible future development.
Humans
;
Coronary Vessels/diagnostic imaging*
;
Fractional Flow Reserve, Myocardial
;
Heart
;
Constriction, Pathologic
;
Coronary Stenosis/diagnostic imaging*
6.Coronary Angiography in Isolated Hearts and Its Forensic Application.
Yong Bo WU ; Heng Jun GUO ; Wei Jian CHEN ; Qi Jun LI
Journal of Forensic Medicine 2016;32(5):329-331
OBJECTIVES:
To check the isolated heart by coronary angiography to discover the location, nature and degree of the coronary artery lesions more accurately and increase the comprehensive evaluation ability of cardiovascular disease.
METHODS:
Ten fresh isolated hearts with different causes of death were extracted and injected with barium sulphate as contrast substance by ring injector, then developed under Xper FD20 angiography equipment. The obtained pictures and image data were handled by three-dimensional angiography images with the software attached to the angiography equipment. The coronary artery tissues were HE stained and observed by microscope. The HE staining results were compared with the angiographic results.
RESULTS:
The imaging data obtained from the 10 cases for examination showed 8 cases without coronary artery stenosis and 2 cases with Ⅲ, Ⅳ coronary artery stenosis, which were consistent with HE staining results of coronary artery organization and the both results were confirmed.
CONCLUSIONS
Isolated coronary angiography has an unique advantage for accurate grading of classification of coronary artery stenosis, examination of vascular malformation and tiny lesions, which can provide reference for the localization of small lesions and basis during the autopsy for identification conclusion.
Autopsy
;
Coronary Angiography
;
Coronary Stenosis/diagnostic imaging*
;
Coronary Vessels/pathology*
;
Heart/diagnostic imaging*
;
Humans
;
Imaging, Three-Dimensional
;
In Vitro Techniques
7.Feasibility of Non-contrast-enhanced Coronary Magnetic Resonance Angiography at 3.0T.
Jing-Wen DAI ; Jian CAO ; Lu LIN ; Xiao LI ; Yi-Ning WANG ; Zheng-Yu JIN
Acta Academiae Medicinae Sinicae 2020;42(2):216-221
To evaluate the feasibility of non-contrast-enhanced magnetic resonance angiography (NCE-MRA) on a 3.0T scanner. Totally 36 volunteers and 24 patients with clinically suspected coronary artery disease underwent NCE-MRA. The quality of the NCE-MRA images was graded for each segment on a four-point scale. The subjects were divided into two groups according to image quality. The age,body mass index (BMI),heart rate,end-expiratory diaphragm displacement,and respiratory diaphragm motion amplitude were evaluated and compared. The average image quality score of every segment was above 2 points. The proximal and middle segments of left anterior descending artery had significantly higher quality scores than the distal segments (=0.000) and the proximal segment of left circumflex coronary artery had significantly higher quality scores than the distal segments (=0.000),the proximal segment of right coronary artery also had a significant higher quality score than its distal segment (=0.001). The image quality was good in 38 subjects (64.4%). The heart rate [(66.35±9.39) beat/min (75.32±11.67) beat/min] (=0.002) and the body mass index [(24.72±3.33) kg/m (27.82±3.61) kg/m ] (=0.002) were significantly different between the good image quality group and the poor image quality group. The end-expiratory diaphragm displacement in good image quality group was (4.43±2.07)mm,which was significantly lower than that in poor image quality group [(9.26±7.62)mm](=0.013). The respiratory diaphragm motion amplitude [(21.35±6.02) mm] in good image quality group was significantly lower than that in poor image quality group [(30.68±14.20)mm](=0.012). NCE-MRA on 3.0T is a feasible tool for visualization of the proximal and middle segments of coronary arteries,and the image quality can be optimized by controlling heart rate and respiration in the future.
Contrast Media
;
Coronary Angiography
;
Coronary Artery Disease
;
diagnostic imaging
;
Coronary Vessels
;
diagnostic imaging
;
Feasibility Studies
;
Humans
;
Magnetic Resonance Angiography
8.The Use of Cardiac Magnetic Resonance in Patients with Suspected Coronary Artery Disease: A Clinical Practice Perspective.
Journal of Cardiovascular Ultrasound 2016;24(2):96-103
Cardiac magnetic resonance imaging (CMR) is a useful diagnostic imaging modality in patients with known or suspected coronary artery disease (CAD). It provides unique information not available from other modalities, however, it is complex. CMR is not a single technique. Instead, it consists of multiple distinct techniques and a lack of understanding of which techniques to perform and how to interpret the findings in combination limits its efficacy and widespread use. Conversely, its multiparametric nature can provide a comprehensive assessment with the potential for higher accuracy than is achievable by other modalities. Moreover, its ability to directly assess myopathic processes often contributes insights that change patient management. In this article we provide a brief technical overview and focus on specific clinical scenarios in patients with known or suspected CAD. We highlight the multiparametric nature of CMR and discuss cases which illustrate the unique information that CMR can contribute.
Coronary Artery Disease*
;
Coronary Vessels*
;
Diagnostic Imaging
;
Humans
;
Magnetic Resonance Imaging
9.Optimized quantitative angiographic and intravascular ultrasound parameters predicting the functional significance of single de novo lesions in the left anterior descending artery.
Tak W KWAN ; Song YANG ; Bo XU ; Jack CHEN ; Tian XU ; Fei YE ; Jun-Jie ZHANG ; Nai-Liang TIAN ; Zhi-Zhong LIU ; Shao-Liang CHEN
Chinese Medical Journal 2012;125(23):4249-4253
BACKGROUNDThe correlation between angiographic or intravascular ultrasound (IVUS) variables and fractional flow reserve (FFR) in patients with single left anterior descending artery (LAD) lesion has not been studied. The current study aimed at determining the best cutoff value of angiographic and IVUS parameters for defining FFR < 0.80 in patients with LAD lesion.
METHODSQuantitative coronary analysis, IVUS and FFR measurements were undergone in 169 patients with single LAD lesion. The best angiographic and IVUS cutoff value and their predictive value for FFR < 0.80 were compared using area under the receiver-operator characteristic curve (AUC) in overall patients or in subgroups stratified by lesion sites.
RESULTSFFR < 0.80 was found in 99 lesions (58.6%). Minimal lumen area (MLA), and plaque burden (PB) were two predictors of FFR < 0.80. Lesion length had less value in predicting FFR < 0.80. The cutoff value of PB and MLA for FFR < 0.80 was 75.4% and 3.03 mm(2). MLA and PB had similar high diagnostic value for proximal (cutoff value 3.04 mm(2) and 76.5%) and distal LAD lesion (2.82 mm(2) and 80.6%). Combination of MLA (2.82 mm(2)) and PB (80.6%) had increased diagnostic value for distal LAD lesion.
CONCLUSIONSMLA and plaque burden had equivalent diagnostic value for FFR < 0.80 when lesion localized in LAD. The predictive value of combination of MLA and plaque burden for distal LAD lesion was strengthened.
Coronary Angiography ; methods ; Coronary Artery Disease ; diagnostic imaging ; Coronary Vessels ; diagnostic imaging ; Female ; Humans ; Male ; Middle Aged ; Plaque, Atherosclerotic ; diagnostic imaging ; Ultrasonography, Interventional ; methods
10.Relationship between coronary arterial remodeling and plaque composition assessed by intravascular ultrasound imaging.
Hong-yi WU ; Ju-ying QIAN ; Feng ZHANG ; Bing FAN ; Xue-bo LIU ; Lei GE ; Yan LU ; Qi-bing WANG ; Jun-bo GE
Chinese Journal of Cardiology 2005;33(10):894-898
OBJECTIVEDuring progression of atherosclerosis, the vessel may develop either positive or negative remodeling. The pathophysiology of vascular remodeling is not fully understood. This study investigated the relationship between plaque characteristics and arterial remodeling using intravascular ultrasound imaging (IVUS).
METHODSA total of 77 patients (male 53, mean age 58 +/- 10 years) who underwent IVUS imaging (ClearView or Galaxy2, Boston Scientific, USA) of culprit vessel were enrolled in this study. Among the 77 patients, 31 presented with stable angina pectoris and 46 presented with acute coronary syndrome. Qualitative assessment of the lesion and quantitative measurement were performed in both stenotic and reference segments. The lesions were classified into soft plaque and hard plaque (including fibrous plaque, calcified plaque and mixed plaque) according to different ultrasound patterns of tissue reflection. The remodeling index (RI) was defined as the ratio of vessel cross sectional area (EEMcsa) of lesion segment to the mean reference EEMcsa. Positive remodeling was defined as RI > 1.0 and negative remodeling as RI < 1.0.
RESULTSOf 77 lesions, 45 (58%) had undergone positive remodeling, and 32 (42%) had negative remodeling. In comparison to the patients with negative remodeling, patients with positive remodeling presented with more acute coronary syndrome (74% vs. 43%, P = 0.006). Both the plaque area and the vessel area were significantly larger in the lesion with positive remodeling than in lesion with negative remodeling. The lesions with positive remodeling were predominantly soft (71% vs. 34%, P = 0.001) and had less calcification [21% vs. 54%, P = 0.003 and (18 +/- 37) degrees vs. (40 +/- 50) degrees, P = 0.027] compared with lesions with negative remodeling. The difference of clinical presentation and plaque characteristics between the patients with different patterns of remodeling is still significant with binary logistic analysis.
CONCLUSIONSCoronary arterial remodeling pattern is related to the clinical manifestation and the composition of plaque. Lesions presented with positive remodeling have a higher prevalence of soft plaque and less calcification.
Aged ; Coronary Disease ; diagnostic imaging ; physiopathology ; Coronary Vessels ; diagnostic imaging ; physiopathology ; Female ; Humans ; Male ; Middle Aged ; Ultrasonography, Interventional