血管内超声和光学相干断层成像对冠状动脉粥样硬化斑块的诊治价值

冠状动脉性心脏病(CHD)亦称缺血性心脏病,其发病率和死亡率长期居世界首位。冠状动脉造影术(CAG)仍是目前诊断CHD的金标准,并广泛应用于CHD的诊疗中,但CAG的分辨率较低,对冠状动脉病变的内膜、外膜和详细病理变化的观察不够精确。血管内超声(IVUS)和光学相干断层成像(OCT)是两种分辨率较高的血管内成像技术,对CHD的诊断和介入治疗起到了很好的补充作用,目前临床上应用也日趋广泛。本文从IVUS和OCT识别冠状动脉粥样硬化斑块、指导和评价经皮冠状动脉介入术的研究现状进行综述。     

Assessment of coronary intima--media thickness by optical coherence tomography: comparison with intravascular ultrasound.

BACKGROUND: Optical coherence tomography (OCT) is a new imaging method. With a resolution of approximately 10-20 Em, which is approximately 10-fold higher than that of intravascular ultrasound (IVUS). METHODS AND RESULTS: This study compared the coronary intima - media thickness (IMT) and the intimal thickness of 54 coronary arterial segments evaluated by histological examination with the results of OCT and IVUS. There was better agreement in IMT between OCT and histological examination than between IVUS and histological examination (r = 0.95, p < 0.001, mean difference = -0.01+/-0.07 mm for OCT; r = 0.88, p < 0.001, mean difference = -0.03+/-0.10 mm for IVUS). There was good agreement in the intimal thickness between OCT and histological examination (r = 0.98, p < 0.001, mean difference = 0.01+/-0.04 mm). CONCLUSIONS: IMT could be measured more accurately by OCT than IVUS. In addition, the intimal thickness could be evaluated by OCT and correlated well with the histological examination.     

Assessing atherosclerotic plaque morphology: comparison of optical coherence tomography and high frequency intravascular ultrasound.

BACKGROUND: OCT can image plaque microstructure at a level of resolution not previously demonstrated with other imaging techniques because it uses infrared light rather than acoustic waves. OBJECTIVES: To compare optical coherence tomography (OCT) and intravascular ultrasound (IVUS) imaging of in vitro atherosclerotic plaques. METHODS: Segments of abdominal aorta were obtained immediately before postmortem examination. Images of 20 sites from five patients were acquired with OCT (operating at an optical wavelength of 1300 nm which was delivered to the sample through an optical fibre) and a 30 MHz ultrasonic transducer. After imaging, the microstructure of the tissue was assessed by routine histological processing. RESULTS: OCT yielded superior structural information in all plaques examined. The mean (SEM) axial resolution of OCT and IVUS imaging was 16 (1) and 110 (7), respectively, as determined by the point spread function from a mirror. Furthermore, the dynamic range of OCT was 109 dB compared with 43 dB for IVUS imaging. CONCLUSIONS: OCT represents a promising new technology for intracoronary imaging because of its high resolution, broad dynamic range, and ability to be delivered through intravascular catheters.     

The comparison between optical coherence tomography and intravascular ultrasound

Coronary angiography, despite its long history, has well recognized limitations, arising in part from the inability to image a three dimensional structure in a single plane. Furthermore the angiographic image of the arterial lumen conceals atherosclerotic processes that occur within the arterial wall. Alternative imaging techniques have evolved as an adjunct to angiography in an attempt to overcome these limitations. Two such invasive techniques are intravascular ultrasound and optical coherence tomography. Intravascular ultrasound allows tomographic imaging of long segments of the coronary tree, highlighting the arterial lumen as well as the arterial wall. Over the last 13 years intravascular ultrasound has enhanced our understanding of the pathophysiology of atherosclerosis, and the mechanisms involved in coronary intervention. Optical coherence tomography is an optical analogue of intravascular ultrasound that has recently reached coronary application. Its superior resolution results in improved diagnostic potential, particularly for vulnerable plaque in which the thin fibrous cap often measures 10-50 mm. The similarities, contrasts and applications of these two imaging techniques in terms of design, image interpretation, and future directions forms the subject of this review.     

糖尿病患者冠状动脉粥样硬化病变的虚拟组织学血管内超声研究

目的 使用虚拟组织学血管内超声(virtual histology intravascular ultrasound,VH-IVUS)评价2型糖尿病患者冠状动脉粥样硬化斑块的组织成分和形态特征.方法 在2008年9月至2009年3月,前瞻性连续收集冠状动脉造影提示的、三支主要血管中直径狭窄≥50%的原位粥样斑块病变,进行灰阶血管内超声以及二维和体积法VH-IVUS分析.根据患者临床资料分为糖尿病(DM)组22例(39个病变)和非DM组46例(69个病变).结果 在最小管腔面积处,DM组斑块的坏死核心(19.4%±1.2%比15.1%±1.1%,P=0.015)和钙化成分(15.2%±1.6%比10.7%±1.1%,P=0.016)较非DM组更多,而纤维组织(56.7%±2.3%比64.8%±1.8%,P=0.007)更少;同样,体积法VH-IVUS发现DM组的坏死核心体积(21.3%±1.3%比16.5%±1.1%,P=0.008)和钙化组织体积(16.6%±1.4%比11.3%±1.1%,P=0.003)更大,而纤维组织体积(55.1%±2.1%比63.9%±1.8%,P=0.003)更小.此外,DM组薄帽纤维粥样硬化斑块的发生率(69.2%)较非DM组(42.O%)更高(P=0.009).然而,斑块重构系数和正性重构发生率在两组差异均无统计学意义.结论 相对于非DM患者,DM患者冠状动脉狭窄性粥样斑块的坏死和钙化组织含量更多,易损斑块也更多见.     

糖尿病患者冠状动脉粥样硬化病变的虚拟组织学血管内超声研究

Objective To evaluate the components and characteristics of coronary atherosclerotic plaques in type 2 diabetic patients using virtual histology intravascular ultrasound (VH-IVUS). Methods In vivo atherosclerotic plaques ( over 50% angiographic diameter stenosis ) of the three main coronary arteries were analyzed by gray-scaled IVUS with planar and volumetric VH-IVUS in consecutive patients examined between September 2008 and March 2009. Patients were divided into two groups: diabetic mellitus (DM) group with 22 patients (39 lesions) and non-DM group with 46 patients (69 lesions). Results At the minimal lumen area (MLA) site, the percentage of NC (necrotic core) area (19.4% ± 1.2% vs.15.1% ± 1.1%, P =0. 015) and dense calcium (DC) area (15.2% ± 1.6% vs. 10. 7% ± 1.1%, P =0. 016) were significantly larger while fibrotic tissue (FT) area (56. 7% ±2. 3% vs. 64. 8% ± 1.8%, P =0. 007) was smaller in DM group than in non-DM group. Likewise, volumetric VH-IVUS analysis showedthat the percentage of NC volume (21.3% ± 1.3% vs. 16. 5% ± 1.1%, P = 0. 008) and DC volume (16.6% ±1.4% vs. 11.3% ±1.1%, P=0.003) were significantly larger while FT volume (55. 1% ±2. 1% vs. 63.9% ± 1.8%, P =0.003) was significantly smaller in DM group than in non-DM group.Moreover, significantly higher incidence of VH-TCFA (thin-cap fibroatheromas) was evidenced in the DM group than in the non-DM group (69. 2% vs. 42. 0%, P =0. 009). However, the remodeling index and the positive remodeling frequency were similar between the 2 groups. Conclusion Incidence of necrotic core, dense calcium plaque and vulnerable plaques in stenotic lesions was higher in DM patients than in non-DM patients.     

糖尿病患者冠状动脉粥样硬化病变的虚拟组织学血管内超声研究

Objective To evaluate the components and characteristics of coronary atherosclerotic plaques in type 2 diabetic patients using virtual histology intravascular ultrasound (VH-IVUS). Methods In vivo atherosclerotic plaques ( over 50% angiographic diameter stenosis ) of the three main coronary arteries were analyzed by gray-scaled IVUS with planar and volumetric VH-IVUS in consecutive patients examined between September 2008 and March 2009. Patients were divided into two groups: diabetic mellitus (DM) group with 22 patients (39 lesions) and non-DM group with 46 patients (69 lesions). Results At the minimal lumen area (MLA) site, the percentage of NC (necrotic core) area (19.4% ± 1.2% vs.15.1% ± 1.1%, P =0. 015) and dense calcium (DC) area (15.2% ± 1.6% vs. 10. 7% ± 1.1%, P =0. 016) were significantly larger while fibrotic tissue (FT) area (56. 7% ±2. 3% vs. 64. 8% ± 1.8%, P =0. 007) was smaller in DM group than in non-DM group. Likewise, volumetric VH-IVUS analysis showedthat the percentage of NC volume (21.3% ± 1.3% vs. 16. 5% ± 1.1%, P = 0. 008) and DC volume (16.6% ±1.4% vs. 11.3% ±1.1%, P=0.003) were significantly larger while FT volume (55. 1% ±2. 1% vs. 63.9% ± 1.8%, P =0.003) was significantly smaller in DM group than in non-DM group.Moreover, significantly higher incidence of VH-TCFA (thin-cap fibroatheromas) was evidenced in the DM group than in the non-DM group (69. 2% vs. 42. 0%, P =0. 009). However, the remodeling index and the positive remodeling frequency were similar between the 2 groups. Conclusion Incidence of necrotic core, dense calcium plaque and vulnerable plaques in stenotic lesions was higher in DM patients than in non-DM patients.     

光学相干断层成像和血管内超声在冠状动脉介入手术中的应用

目的 应用光学相干断层成像(OCT)及血管内超声(IVUS)检测技术评价冠状动脉内粥样硬化斑块的稳定性,并指导支架置入,检测血管对置入支架后即刻和中远期的反应.方法 选择2008年2-7月间的27例患者,进行冠状动脉造影、OCT及IVUS检查,共检查了30支血管,其中8处为药物支架植入术后血管,并对19处病变进行了支架置入.结果 除外支架置入的8例(置入6个月～4年)外,其余22例病变行OCT及IVUS检查,发现稳定性斑块5例,不稳定斑块17例,其中OCT检出内膜小撕裂4例(IVUS未检出,P＞0.05),冠状动脉撕裂伴夹层病变5例(IVUS检出1例,P＞0.05),血栓形成5例(IVUS检出1例,P＞0.05),偏心斑块伴薄纤维帽12例(IVUS检出2例,P＜0.01).8例曾经进行支架治疗的患者,造影、OCT和IVUS发现2例再狭窄;OCT显示支架内膜覆盖良好,IVUS小能精确看到内膜;OCT检测出1例患者有支架后瘤样扩张.对17例不稳定性斑块及2例支架再狭窄病例行支架置入术,术后支架膨胀不良发生率26.0%,OCT及IVUS检出率相同;支架贴壁不良发生率63.2%,IVUS榆出率低于OCT(10.5%比63.2%,P＜0.01);支架近远端撕裂10.5%,IVUS均不能检出;内膜脱垂发生率52.6%,IVUS检出率低于OCT(10.5%比52.6%,P＜0.05).结论 OCT与IVUS相比,在不稳定性斑块检测准确度方面明显优于IVUS,更能精确指导冠状动脉支架置人.IVUS在操作简便性及反映斑块负荷方面要优于OCT.     

Diagnostic accuracy of optical coherence tomography and intravascular ultrasound for the detection and characterization of atherosclerotic plaque composition in ex-vivo coronary specimens: a comparison with histology

BACKGROUND: Both intravascular ultrasound and optical coherence tomography have been purported to accurately detect and characterize coronary atherosclerotic plaque composition. The aim of our study was to directly compare the reproducibility and diagnostic accuracy of optical coherence tomography and intravascular ultrasound for the detection and characterization of coronary plaque composition ex vivo as compared with histology. METHODS AND RESULTS: Intravascular ultrasound (20 MHz) and optical coherence tomography imaging was performed in eight heart specimens using motorized pullback. Standard histology using hematoxylin-eosin and van Gieson staining was performed on 4 mum thick slices. Each slice was divided into quadrants and accurately matched cross-sections were analyzed for the presence of fibrous, lipid-rich, and calcified coronary plaque using standard definitions for both intravascular ultrasound and optical coherence tomography and correlated with histology. After exclusion of 145/468 quadrants, we analyzed the remaining 323 quadrants with excellent image quality in each procedure. Optical coherence tomography demonstrated a sensitivity and specificity of 91/88% for normal wall, 64/88% for fibrous plaque, 77/94% for lipid-rich plaque, and 67/97% for calcified plaque as compared with histology. Intravascular ultrasound demonstrated a sensitivity and specificity of 55/79% for normal wall, 63/59% for fibrous plaque, 10/96% for lipid-rich plaque, and 76/98% for calcified plaque. Both intravascular ultrasound and optical coherence tomography demonstrated excellent intraobserver and interobserver agreement (optical coherence tomography: kappa=0.90, kappa=0.82; intravascular ultrasound: kappa=0.87, kappa=0.86). CONCLUSION: Optical coherence tomography is superior to intravascular ultrasound for the detection and characterization of coronary atherosclerotic plaque composition, specifically for the differentiation of noncalcified, lipid-rich, or fibrous plaque.     

Diagnostic accuracy of optical coherence tomography and integrated backscatter intravascular ultrasound images for tissue characterization of human coronary plaques.

OBJECTIVES: The purpose of the present study was to validate the diagnostic accuracy of optical coherence tomography (OCT), integrated backscatter intravascular ultrasound (IB-IVUS), and conventional intravascular ultrasound (C-IVUS) for tissue characterization of coronary plaques and to evaluate the advantages and limitations of each of these modalities. BACKGROUND: The diagnostic accuracy of OCT for characterizing tissue types is well established. However, comparisons among OCT, C-IVUS, and IB-IVUS have not been done. METHODS: We examined 128 coronary arterial sites (42 coronary arteries) from 17 cadavers; IVUS and OCT images were acquired on the same slice as histology. Ultrasound signals were obtained using an IVUS system with a 40-MHz catheter and digitized at 1 GHz with 8-bit resolution. The IB values of the ultrasound signals were calculated with a fast Fourier transform. RESULTS: Using histological images as a gold standard, the sensitivity of OCT for characterizing calcification, fibrosis, and lipid pool was 100%, 98%, and 95%, respectively. The specificity of OCT was 100%, 94%, and 98%, respectively (Cohen's kappa = 0.92). The sensitivity of IB-IVUS was 100%, 94%, and 84%, respectively. The specificity of IB-IVUS was 99%, 84%, and 97%, respectively (Cohen's kappa = 0.80). The sensitivity of C-IVUS was 100%, 93%, and 67%, respectively. The specificity of C-IVUS was 99%, 61%, and 95%, respectively (Cohen's kappa = 0.59). CONCLUSIONS: Within the penetration depth of OCT, OCT has a best potential for tissue characterization of coronary plaques. Integrated backscatter IVUS has a better potential for characterizing fibrous lesions and lipid pools than C-IVUS.     

血管内超声与光学相干断层扫描在冠状动脉临界病变中的长期随访对比研究

目的:研究血管内超声(intravenous ultrasound,IVUS)与光学相干断层扫描(optical coher-ence tomography,OCT)在冠状动脉临界病变中的长期随访研究。方法:共入选经过冠状动脉造影(至少4体位造影)证实病变狭窄处于临界病变的患者90例。将入选者按照2∶1随机分为:血管内超声组(IVUS)60例,光学相干断层成像(OCT)组30例。通过血管内超声定量分析最小管腔直径、参考血管直径、最小管腔面积等参数指标;通过光学相干断层扫描分析最小管腔直径、最小管腔面积。同时依据两组检查方法不同特征确定斑块的性质进行定性亚组分析:纤维性斑块、钙化斑块及脂质斑块等,对于高危易损斑块进行冠状动脉介入治疗,术后规律服用药物,观察两组术后住院期间、30d、3个月、9个月、1年和2年的主要心血管事件。采用COX回归模型分析两组2年内免于心血管事件的差异。结果:IVUS和OCT进行亚组软斑块分析,两组测得最小管腔直径分别为[(1.84±0.06)vs.(1.84±0.13)mm,P=0.947]。另外,在最小管腔面积方面两组分别为[(4.7±0.98)vs.(4.8±1.17)mm2,P=0.853]。OCT组通过分析软斑块纤维帽厚度为(94±24.72)μm。通过COX回归模型显示,两组在免于心血管事件的差异无统计学意义(P=0.826)。结论:对于临界病变的患者,采用IVUS或OCT成像系统能够更好的分辨血管内斑块性质,尤其易识别易损斑块。对于临界病变的患者,采用介入影像学方法进行测量分析是安全的、可靠的,能更好指导临床治疗。     

64层CT与血管内超声对冠状动脉粥样斑块的定性和定量评估的对照研究

目的 对照血管内超声（intravascular ultrasound,IVUS）评价64层CT对冠状动脉粥样斑块的定性检测和定量分析。方法 2005年7月至10月连续纳入12例拟行PCI的稳定性心绞痛患者进行研究。所有患者术前接受64层CT的冠状动脉成像,术中行三支冠状动脉（左前降支、回旋支和右冠状动脉）的IVUS检查。结果 共对31支血管（左前降支12支,回旋支10支,右冠状动脉9支）,88个节段进行了64层CT和IVUS的对比检查,其中64层CT可评价节段为68个。在IVUS检测到的51个有斑块节段中,64层CT检测出47个（敏感性92％）,在17个IVUS判断为无斑块的节段中,64层CT判断16个为无斑块（特异性94％）。64层CT测量的斑块面积和IVUS测量的斑块面积相关（r=0．53,P〈0．01）,但是高估了斑块面积[（9．09±3．89）mm。比（6．80±2．81）mm^2,P〈0．01]。64层CT在43个IVUS测定的低回声成分中检出30个为低密度成分,平均CT值67．39HU。结论 冠状动脉无严重钙化时,64层CT可准确检测冠状动脉近中段粥样斑块。64层CT测量的斑块面积虽然和IVUS测量结果相关,但准确测量受限。     

Treatment of a giant coronary artery aneurysm: intravascular ultrasound and optical coherence tomography findings

A giant coronary aneurysm (GCA) partially thrombosed was demonstrated in a 77-year-old patient evaluated for an inferior myocardial infarction. Primary angioplasty (balloon only) with suboptimal result was initially obtained. After triple antiplatelet and anticoagulation therapy (4 days), a new angiography was performed and a fusiform GCA was clearly delineated. A second percutaneous intervention was performed using a "scaffolding technique" with conventional stent and subsequent implantation of 2 polytetrafluoroethylene-covered stents to successfully exclude the aneurysm. This case demonstrates a novel technique to treat long GCA.