Diagnostic Imaging ; trends ; Humans ; Plaque, Atherosclerotic ; diagnosis

BACKGROUNDNo clinical study has systematically analyzed and compared circumferential neointimal and plaque distribution of stent neointimal proliferation and in native atherosclerotic plaques. This study aimed to investigate and compare the pattern of instent neointimal formation and native atherosclerosis in the coronary bifurcation lesions by volumetric analysis using systematic intravascular ultrasound (IVUS).

METHODSWe examined bifurcation lesions in native coronary artery (plaque group, n = 102) and stented bifurcations at 9-month follow-up (neointima group, n = 51) using volumetric IVUS analysis of both the main vessel (MV) and side branch (SB). Three 5-mm segments were analyzed; the proximal MV (MVp), distal MV (MVd) and SB ostium (SBo). For each segment, volumetric analysis was performed in each of four quadrants (divided according to the branch takeoff and the geometric center of the lumen); carinal, epicardial, abcarinal, and myocardial. The eccentricity index was defined as the ratio of the abcarinal plaque (or neointimal) volume to the carinal plaque (or neointimal) volume.

RESULTSThe plaque distribution differed significantly between the four quadrants, with the largest in the abcarinal quadrant, followed by the myocardial, epicardial, and carinal quadrants. The distribution of neointima was similar in the MV, but the four quadrants in the SB did not differ significantly. The eccentricity indices of both the MVd (P < 0.001) and SBo (P = 0.001) were significantly higher for the plaque group than the neointima group.

CONCLUSIONSThe distribution of neointimal proliferation seems to have a similar pattern to that of atherosclerotic plaque in native coronary arteries, particularly in the main vessel, but the trend is less prominent.

Aged ; Coronary Artery Disease ; diagnostic imaging ; Female ; Humans ; Male ; Middle Aged ; Neointima ; diagnostic imaging ; Plaque, Atherosclerotic ; diagnostic imaging ; Ultrasonography

BACKGROUNDAtherosclerotic plaque rupture is the primary mechanism of thrombosis which plays a key role in the onset of acute coronary syndromes. Detection of these plaques prone to rupture (vulnerable plaque) could be clinically significant for prevention of cardiac events. It has been shown that high metabolism cells have a high uptake of fluorine-18 fluorodeoxyglucose ((18)F-FDG). The objective of this study was to investigate the correlation of FDG uptake and the immuno-histochemistry parameters of plaques, and the effect of atorvastatin on vulnerable atherosclerotic plaque in a rabbit model.

METHODSTen male New Zealand White rabbits were divided into three groups as follows: (1) normal control group (n = 2, C group): the animals were fed a standard diet at 120 g/d and were given water ad labium; (2) atherosclerosis group (n = 4, As group): animals were fed with high fat diet for 5 months after aortic endothelia damage; (3) treatment group (atherosclerosis + atorvastatin, n = 4, Statin group): animals were fed with high fat diet for 5 months and then changed into normal chow plus atorvastatin (2.5 mg·d(-1)·kg(-1)) treatment for another 4 months. Then these four rabbits were imaged with fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) and sacrificed for pathohistologic studies. FDG uptake by the aorta was expressed as target-to-background ratio (TBR). Maximal standardized uptake value (SUV) was measured over the thoracic and abdominal aortas. The aortic smooth muscle cell (SMC) number, CD-14 antibody positive cell (macrophage) number and the ratio of the thickness of fibrous cap to the thickness of lipid core (cap-to-core ratio) in atherosclerotic plaques were analyzed.

RESULTSAs group showed significantly higher uptake of FDG than C group (SUVs: 0.746 ± 0.172 vs. 0.286 ± 0.073, P < 0.001). After 4 months of atorvastatin treatment and the modification of diet, SUVs decreased significantly (Statin group: 0.550 ± 0.134, compared to As group, P < 0.001). However, no marked difference was found in TBR, the number of macrophages, the number of SMC and the cap-to-core ratio in the aortic segments between Statin group and As group. The correlation of aortic FDG uptake with SMC assessed by histopathology was negatively significant (r = -0.57, P < 0.001). When aortic FDG uptake was expressed as TBR, it correlated significantly (r = 0.69, P < 0.001) with the macrophage number, and also correlated significantly (r = -0.78, P < 0.001) with the cap-to-core ratio.

CONCLUSION(18)F-FDG PET/CT might serve as a useful non-invasive imaging technique for detection of atherosclerotic plaque and potentially permit monitoring of relative changes in inflammation within the atherosclerotic lesion.

Animals ; Aorta ; diagnostic imaging ; pathology ; Atherosclerosis ; diagnostic imaging ; Fluorodeoxyglucose F18 ; Male ; Plaque, Atherosclerotic ; diagnostic imaging ; Positron-Emission Tomography ; methods ; Rabbits

Intravascular ultrasound (IVUS) is widely used in coronary artery examination. Ultrasonic elastography combined with IVUS is very conspicuous in identifying plaque component and in detecting plaque vulnerability degree. In this study, a simulation model of the blood vessel based on finite element analysis (FEA) was established. The vessel walls generally have radial changes caused by different intravascular pressure. The signals at lower pressures were used as the pre-deformation data and the signals at higher pressure were used as the post-deformation data. Displacement distribution was constructed using the time-domain cross-correlation method, and then strain images. By comparison of elastograms under different pressures, we obtained the optimal pressure step. Furthermore, on the basis of the obtained optimize pressure step, the simulation results showed that this method could effectively distinguish characteristics between different component plaques, and could guide the later experiments and clinical applications.
Angiography ; Arteries ; diagnostic imaging ; pathology ; Elasticity Imaging Techniques ; Finite Element Analysis ; Humans ; Plaque, Atherosclerotic ; diagnostic imaging ; Pressure

OBJECTIVEApoptosis contributes to the instability of the atherosclerotic (AS) lesions. The vulnerable plaque was identified in vivo by detecting the apoptosis with radiolabeled annexin V in an atherosclerotic rabbit model.

METHODSEight male New Zealand white rabbits on 2% cholesterol diet for 2 weeks had abdominal aortic balloon injury and fed a 2% cholesterol diet for another 15 weeks (AS group), 3 rabbits fed a normal rabbit chow for 17 weeks without balloon injury served as controls. Annexin V labeled with (99)Tc(m) was then intravenously administered and planar whole-body images were captured using a gamma camera in the left lateral position. The entire length of the abdominal aorta was explanted for ex vivo imaging with gamma camera. The aorta then was divided into several segments according to the severity of AS. The segments were separated weighted and counted in an gamma counter for the absorptive dose of annexin per gram of tissue. Histology examinations were made on specimens.

RESULTSAt 2 hours post annexin V injection, clear delineation of radiolabel within the abdominal aorta could be evidenced in vivo gamma imaging. After explanation of the aorta, ex vivo imaging showed a robust uptake of radiotracer in the infradiaphragmatic aorta corresponding to the in vivo images and conforming to the macroscopic distribution of atherosclerotic lesions. The uptake of radiolabel was absent in areas without grossly visible atherosclerotic lesions. The in vivo and ex vivo images identified plaque areas were identical and corresponded histological results on the explanted specimen. The aortic specimen was divided into 18 segments on lesions. The magority of the lesions (14/18) manifested as type IV or type V lesions of AHA classification (vulnerable lesions), except segments 1 - 4, which manifested as type I or type II lesions. The thickness of fibrous cap (TFC) and the ratio of cap and lipid nuclear (RCN) were significantly reversely correlated to the unit radioactivity counts, and the correlation between RCN and the unit radioactivity counts was more significant than that between TFC and the unit radioactivity counts (r = -0.904, P < 0.01, and r = -0.8, P < 0.01). Apoptosis detection (TUNEL): annexin V intake in plaques was positively correlated to apoptotic index(r = 0.651, P = 0.012).

CONCLUSIONNoninvasive Annexin V imaging could be used to detect vulnerable atherosclerotic plaques in vivo.

Animals ; Annexin A5 ; Aorta, Abdominal ; Atherosclerosis ; Cholesterol, Dietary ; Diagnostic Imaging ; Plaque, Atherosclerotic ; Rabbits

Atherosclerosis is a complex and multi-factorial pathophysiological process. Researches over the past decades have shown that the development of atherosclerotic vulnerable plaque is closely related to its components, morphology, and stress status. Biomechanical models have been developed by combining with medical imaging, biological experiments, and mechanical analysis, to study and analyze the biomechanical factors related to plaque vulnerability. Numerical simulation could quantify the dynamic changes of the microenvironment within the plaque, providing a method to represent the distribution of cellular and acellular components within the plaque microenvironment and to explore the interaction of lipid deposition, inflammation, angiogenesis, and other processes. Studying the pathological mechanism of plaque development would improve our understanding of cardiovascular disease and assist non-invasive inspection and early diagnosis of vulnerable plaques. The biomechanical models and numerical methods may serve as a theoretical support for designing and optimizing treatment strategies for vulnerable atherosclerosis.
Atherosclerosis ; Biomechanical Phenomena ; Computer Simulation ; Humans ; Inflammation ; Models, Cardiovascular ; Plaque, Atherosclerotic/diagnostic imaging*

OBJECTIVETo investigate the difference in the vulnerability of carotid atherosclerotic plaques in patients with unilateral and bilateral intraplaque hemorrhage (IPH).

METHODSA retrospective analysis was conducted among 44 patients with unilateral IPH (30 cases) or bilateral IPH (14 cases) in the carotid plaques detected by magnetic resonance imaging (MRI) in our hospital between December, 2009 and December, 2012. The age, maximum wall thickness and incidence of fibrous cap rupture were compared between the two groups.

RESULTSCompared with those with unilateral IPH, the patients with bilateral IPHs had a significantly younger age (66.6∓9.4 years vs 73.7∓9.0 years, P=0.027), a significantly greater maximum plaque thickness (6.3∓1.9 mm vs 5.0∓1.3 mm, P=0.035) and a higher incidence of ulcers (50% vs 13.3%, P=0.025). Logistic regression analysis revealed a significant association between bilateral IPHs and the occurrence of ulcer with an odd ratio (OR) of 6.5 (95% confidence interval [CI]: 1.5-28.7, P=0.014). After adjustment for gender in Model 1, bilateral IPHs were still significantly associated with presence of ulcer (OR=5.7, 95%CI: 1.1-29.2, P=0.036). But after adjustment for age (P=0.131) or maximum plaque thickness (P=0.139) in model 2, no significant correlation was found between bilateral IPHs and the presence of ulcer.

CONCLUSIONCompared with patients with unilateral IPH, those with bilateral IPHs are at a younger age and have a greater plaque burden and a higher incidence of fibrous cap rupture, suggesting a greater vulnerability of the carotid plaques in patients with bilateral IPHs.

Aged ; Carotid Arteries ; diagnostic imaging ; Carotid Stenosis ; diagnostic imaging ; physiopathology ; Fibrosis ; Hemorrhage ; diagnostic imaging ; Humans ; Magnetic Resonance Imaging ; Middle Aged ; Odds Ratio ; Plaque, Atherosclerotic ; diagnostic imaging ; Retrospective Studies

OBJECTIVE: To evaluate the differences of plaquecomposition and volume between symptomatic and asymptomatic patients with carotid artery stenosis by multi-detector computed tomography angiography (MDCTA). METHODS: The consecutive patients with internal carotid artery stenosis≥70% diagnosed by digital subtraction angiography (DSA) were retrospectively analyzed from July 2011 to December 2015 in Peking University China-Japan Friendship School of Clinical Medicine. The symptomatic patients were defined as those who experienced nondisabling ischemic stroke or transient cerebralis chemic symptoms, including hemispheric events oramaurosis fugaxin the last 6 months. Otherwise, the patients were considered as a symptomatic. A total of 78 patients were enrolled in the study. Of these patients, there were 35 asymptomatic patients (44.9%) and 43 symptomatic patients (55.1%). All the patients received MDCTA before DSA. According to the plaque analysis of post processing work station, carotid plaques were divided into lipid-rich necrotic coreplaques (HU≤60), fibrous plaques (60 to 130 HU) and calcified plaques (HU≥130) through the different value sthreshold of HU. The plaque volume and proportion were all calculated. The differences between the two groups were compared by statistical methods. RESULTS: The proportion of calcified plaques in asymptomatic patients was significantly higher than in symptomatic patients (t=2.760, P=0.007).And the proportion of LRNC plaqueswas lower than that in symptomatic patients (Z=2.009, P=0.044). There was statistical significance between the asymptomatic and symptomatic patients. Multivariate analysis showed that there was a positive correlation between the proportion of calcified plaques and asymptomatic carotid artery stenosis (OR=0.949; 95%CI: 0.915 to 0.985; P=0.005). The proportion of LRNC plaques showed a negative correlation with asymptomatic carotid artery stenosis (OR=1.068; 95%CI: 1.021 to 1.117; P=0.004). For the symptomatic patients, when the LRNC plaque proportion was greater than 30.3%, the specificity was 94.3%, and the sensitivity was 37.2%. There was no significant difference in plaque volume and fibrous plaque proportion in both groups. CONCLUSION Compared with symptomatic carotid plaques, the proportion of asymptomatic calcified plaques increased but the proportion of LRNC plaques decreased. Plaque LRNC 30.3% of the total volume may represent a clinically useful cutoff. For the patients with carotid artery stenosis, MDCTA may help noninvasively risk-stratify patients.
Carotid Arteries ; Carotid Stenosis/diagnostic imaging* ; China ; Computed Tomography Angiography ; Humans ; Plaque, Atherosclerotic/diagnostic imaging* ; Retrospective Studies

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

OBJECTIVETo investigate the effect of qingre quyu granule (QQG) for treatment of carotid vulnerable atherosclerotic plaque (CVAP) in patients with coronary heart disease (CHD).

METHODSEighty-two CHD patients with stable exertional angina, complicated with CVAP and differentiated to phlegm-heat and blood-stasis syndrome type were randomly assigned to two groups equally, the test group treated by Western medical routine therapy combined with QQG, and the control group treated with Western medical routine therapy with placebo. Using high frequency ultrasonography, the number (complex and simple) and Crouse integral of CVAP and the intima-media membranous thickness of carotid artery were measured, and changes in serum levels of CD40L and high-sensitivity C-reactive protein (hs-CRP), liver and renal functions were observed.

RESULTSAfter treatment, significant improvement were shown in the test group in terms of complex plaques' number, Crouse integral, intima-media thickness and serum levels of CD40L and hs-CRP as compared with that before treatment, also with those in the control group after treatment (P < 0.05 or P < 0.01). No adverse reaction was found in the treatment course.

CONCLUSIONQQG has certain stabilizing action on CVAP in patients with CHD.

Adult ; Carotid Arteries ; diagnostic imaging ; Coronary Disease ; diagnostic imaging ; drug therapy ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Female ; Humans ; Male ; Middle Aged ; Phytotherapy ; Plaque, Atherosclerotic ; diagnostic imaging ; Ultrasonography