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Optical Coherence Tomography Imaging in Acute Coronary Syndromes
Takashi Kubo,Yasushi Ino,Takashi Tanimoto,Hironori Kitabata,Atsushi Tanaka,Takashi Akasaka
Cardiology Research and Practice , 2011, DOI: 10.4061/2011/312978
Abstract: Optical coherence tomography (OCT) is a high-resolution imaging technique that offers microscopic visualization of coronary plaques. The clear and detailed images of OCT generate an intense interest in adopting this technique for both clinical and research purposes. Recent studies have shown that OCT is useful for the assessment of coronary atherosclerotic plaques, in particular the assessment of plaque rupture, erosion, and intracoronary thrombus in patients with acute coronary syndrome. In addition, OCT may enable identifying thin-cap fibroatheroma, the proliferation of vasa vasorum, and the distribution of macrophages surrounding vulnerable plaques. With its ability to view atherosclerotic lesions in vivo with such high resolution, OCT provides cardiologists with the tool they need to better understand the thrombosis-prone vulnerable plaques and acute coronary syndromes. This paper reviews the possibility of OCT for identification of vulnerable plaques in vivo.
Optical Coherence Tomography Analysis of Attenuated Plaques Detected by Intravascular Ultrasound in Patients with Acute Coronary Syndromes
Takashi Kubo,Yoshiki Matsuo,Yasushi Ino,Takashi Tanimoto,Kohei Ishibashi,Kenichi Komukai,Hironori Kitabata,Atsushi Tanaka,Keizo Kimura,Toshio Imanishi,Takashi Akasaka
Cardiology Research and Practice , 2011, DOI: 10.4061/2011/687515
Abstract: Background. Recent intravascular ultrasound (IVUS) studies have demonstrated that hypoechoic plaque with deep ultrasound attenuation despite absence of bright calcium is common in acute coronary syndrome. Such “attenuated plaque” may be an IVUS characteristic of unstable lesion. Methods. We used optical coherence tomography (OCT) in 104 patients with unstable angina to compare lesion characteristics between IVUS-detected attenuated plaque and nonattenuated plaque. Results. IVUS-detected attenuated plaque was observed in 41 (39%) patients. OCT-detected lipidic plaque (88% versus 49%, <0.001), thin-cap fibroatheroma (48% versus 16%, <0.001), plaque rupture (44% versus 11%, <0.001), and intracoronary thrombus (54% versus 17%, <0.001) were more often seen in IVUS-detected attenuated plaques compared with nonattenuated plaques. Conclusions. IVUS-detected attenuated plaque has many characteristics of unstable coronary lesion. The presence of attended plaque might be an important marker of lesion instability.
TOMOGRAFíA DE COHERENCIA óPTICA Y ANGIOGRAFíA CORONARIA COMO COMPLEMENTO EN DECISIONES TERAPéUTICAS / Optical coherence tomography and coronary angiography as complement in therapeutic decisions  [PDF]
Iguer F. Aladro Miranda,Rosa Lázaro García,Manuel Gómez Recio,Francisco L. Moreno?Martínez
CorSalud , 2012,
Abstract: ResumenLa tomografía de coherencia óptica es una técnica de diagnóstico intracoronario con una alta resolución, su advenimiento ha permitido llevar a cabo un mejor diagnóstico para el tratamiento de las afecciones vasculares. El desarrollo de nuevos sistemas de esta tomografía, que evitan la oclusión de la arteria, favorece que esta técnica tenga mayor utilidad y se convierta en práctica habitual en los laboratorios de hemodinámica, para la caracterización de la placa aterosclerótica coronaria y la evaluación del stent implantado. Se presenta un paciente que en el curso de un síndrome coronario agudo con elevación del segmento ST, fue tratado con trombolíticos y no se lograron signos de reperfusión. La coronariografía realizada no demostró estenosis significativa en relación con la topografía del infarto, por lo que se realizó tomografía de coherencia óptica y se diagnosticó una imagen compatible con proliferación neointimal y presencia de trombo dentro del stent previamente implantado en la arteria circunfleja, que se correspondía con los cambios del electrocardiograma. Se decidió aplicar tratamiento percutáneo con implantación de stent fármaco-activo. La tomografía de coherencia óptica permitió diagnosticar y tratar una imagen angiográfica dudosa. / AbstractOptical coherence tomography is an intracoronary diagnostic technique of high resolution, and its arrival has allowed a better diagnosis for the treatment of vascular diseases. The development of new systems for this tomography, which prevent artery occlusion, allows this technique to have greater utility and become standard practice in the hemodynamic laboratories for the characterization of coronary atherosclerotic plaque and for evaluating the inserted stent. The case of a patient that during an acute coronary syndrome with ST segment elevation was treated with thrombolytics and no signs of reperfusion were achieved is presented. Coronary angiography showed no significant stenosis regarding infarct topography, so an optical coherence tomography was performed and an image compatible with neointimal proliferation and thrombus within the previously inserted stent in the circumflex artery was diagnosed, which corresponded with ECG changes. It was decided to apply percutaneous treatment with drug-eluting stent implantation. Optical coherence tomography allowed diagnosing and treating a dubious angiographic image.
Morphologic Characterization and Quantification of Superficial Calcifications of the Coronary Artery —In Vivo Assessment Using Optical Coherence Tomography—  [PDF]
Nagoya Journal of Medical Science , 2012,
Abstract: Coronary calcification is proportional to the extent and severity of atherosclerotic disease, and is a predictor of cardiac events. Furthermore, coronary calcification protruding into the lumen is considered as one type of vulnerable plaque. Optical coherence tomography (OCT) can provide in vivo imaging of the detailed vessel wall structure of the coronary artery with high resolution, as in the histological approach. We analyzed coronary calcification in that fashion using OCT in vivo. This study consisted of 70 superficial coronary calcifications of 39 consecutive patients who underwent percutaneous coronary intervention. After revascularization, OCT was performed in the treated vessel. We analyzed morphologic characteristics and the quantification of OCT-determined coronary calcification. Superficial coronary calcifications were classified into two groups depending on whether they did not intrude the lumen (type I) or did (type II). The distance from the lumen and the volume of each calcification were then measured. Superficial coronary calcifications were classified into two groups; type I, n = 39 (56%) and type II, n = 31 (44%). Type II calcifications were located significantly closer to the lumen [80 μm (60–130) vs.130 μm (90–260), p = 0.015], and tended to be smaller, but did not show a significant difference [0.65 (0.26–1.3) mm3 vs. 1.2 (0.47–1.9) mm3, p = 0.153] compared to those of type I. In conclusion, OCT could visualize superficial coronary calcifications in detail and enable us to evaluate in vivo morphologic characterizations and quantify them.
Characterization of coronary plaques with combined use of intravascular ultrasound, virtual histology and optical coherence tomography
Guillermo Sánchez-Elvira,Isabel Coma-Canella,Miguel Artaiz,José Antonio Páramo
Heart International , 2010, DOI: 10.4081/hi.2010.e12
Abstract: According to post-mortem studies, luminal thrombosis occurs from plaque rupture, erosion and calcified nodules. In vivo studies have found thin cap fibroatheroma (TCFA) as the main vulnerable lesion, prone to rupture. Few data about other post-mortem lesions have been reported in vivo. Our main objective is to characterize in vivo the coronary plaques with intravascular ultrasound-virtual histology (IVUS-VH) and optical coherence tomography (OCT), in order to detect not only thin cap fibroatheroma (TCFA), but also other possible vulnerable lesions. The secondary objective is to correlate these findings with clinical and analytical data. Twenty-five patients (18 stable) submitted to coronary angiography were included in this pilot study. After angiography, the three vessels were studied (when possible) with IVUS-VH and OCT. Plaque characteristics were correlated with clinical and analytical data. Forty-six lesions were analyzed. IVUS-VH detected significant necrotic core in 15 (3 were definite TCFA). OCT detected TCFA in 10 lesions, erosion in 6, thrombus in 5 and calcified nodule in 8. Possible vulnerable lesion was found in 61% of stable and 57% of unstable patients. Erosions and calcified nodules were only found in stable patients. Those with significant necrotic core had higher body mass index (P=0.016), higher levels of hs-CRP (P=0.019) and triglycerides (P=0.040). The higher the levels of hs-CRP, the larger the size of the necrotic core (r=0.69, P=0.003). Lesions with characteristics of vulnerability were detected by IVUS-VH and OCT in more than 50% of stable and unstable coronary patients. A significant necrotic core was mainly correlated with
Evaluation of coronary plaque and stent deployment by intravascular optical coherence tomography in elderly patients with unstable angina and non-ST-elevation myocardial infarction
Caiyi LU,Shiwen WANG,Wei YAN,Xingli WU,Yuxiao ZHANG,Qiao XUE,Muyang YAN,Peng LIU,Rui CHEN,Jinyue ZHAI,
Caiyi LU
,Shiwen WANG,Wei YAN,Xingli WU,Yuxiao ZHANG,Qiao XUE,Muyang YAN,Peng LIU,Rui CHEN,Jinyue ZHAI

老年心脏病学杂志(英文版) , 2007,
Abstract: Objective To evaluate the feasibility and efficacy of intravascular optical coherence tomography (OCT) in the assessment of plaque characteristics and drug eluting stent deployment quality in the elderly patients with unstable angina (UA) and non-ST segment elevation myocardial infarction (NSTEMI). Methods OCT was used in elderly patients undergoing percutaneous coronary interventions. Fifteen patients, 9 males and 6 females with mean age of 72.6±5.3 years (range 67-92 years) were enrolled in the study. Images were obtained before initial balloon dilatation and following stent deployment. The plaque characteristics before dilation, vessel dissection, tissue prolapse, stent apposition and strut distribution after stent implantation were evaluated. Results Fifteen lesions were selected from 32 angiographic lesions as study lesions for OCT imaging after diagnostic coronary angiography. There were 7 lesions in the left anterior descending artery, 5 lesions in the right coronary artery and 3 lesions in the left circumflex coronary artery. Among them, 12 (80.0%) were lipid-rich plaques, and 10 (66.7%) were vulnerable plaques with fibrous cap thickness 54.2±7.3 |im. Seven ruptured culprit plaques (46.7%) were found; 4 in UA patients and 3 in NSTEMI patients. Tissue prolapse was observed in 11 lesions (73.3%). Irregular stent strut distribution was detected in 8 lesions (53.3%). Vessel dissections were found in 5 lesions (33.3%). Incomplete stent apposition was observed in 3 stents (20%) with mean spacing between the struts and the vessel wall I72±96 mm (range 117-436 mm). Conclusions 1) It is safe and feasible to perform intravascular OCT to differentiate vulnerable coronary plaque and monitor stent deployment in elderly patients with UA and USTEMI. 2) Coronary plaques in elderly patients with UA and USTEMI could be divided into acute ruptured plaque, vulnerable plaque, lipid-rich plaque, and stable plaque. 3) Minor or critical plaque rupture is one of the mechanisms of UA in elderly patients. 4) Present drug eluting stent implantation is complicated with multiple tissue prolapses which are associated with irregular strut distributions. 5) The action and significance of tissue prolapse on acute vessel flow and in-stent thrombus and restenosis need to be further studied.
Coronary vessel intimal sequence extraction based on prior boundary constraints in optical coherence tomography image

- , 2018, DOI: 10.7507/1001-5515.201712058
Abstract: 光学相干断层影像(OCT)是一种应用于血管的影像新技术,其高分辨率和可量化分析等特点,使其能够检测血管内膜和斑块表面的特殊结构并发现微小病变。特别是随着其在识别冠状动脉粥样硬化斑块、优化经皮冠状动脉介入(PCI)治疗、辅助医生制定相关诊断和治疗策略以及支架术后评估等方面的应用相继展开,OCT 已经成为心血管疾病诊断的有效工具。本文提出了一种基于先验边界条件的冠脉 OCT 内膜轮廓序列提取算法,在 Chan-Vese 模型基础上通过改进演化权函数把轮廓曲线的局部信息引入模型,控制曲线边界演化速度,并在模型中加入梯度能量项和基于先验边界条件的内膜轮廓形状限制项,进一步约束曲线演化轮廓的形状,最终实现冠脉血管内膜轮廓的序列提取。与作为金标准的专业医生手动分割结果进行实验对比,结果表明本算法在冠脉 OCT 内膜轮廓模糊、失真、有导丝阴影及有斑块干扰等情况下均能准确提取冠脉血管内膜轮廓,提示本研究成果或可应用于临床辅助诊断和精确诊疗之中。
Optical coherence tomography (OCT) is a new technique applied in cardiovascular system. It can detect vessel intimal, small structure of plaque surface and discover small lesions with its high axial resolution and quantification character. Especially with the application of OCT in characterization of coronary atherosclerotic plaque, diagnosis and treatment strategy making, optimizing percutaneous coronary intervention therapy and assessment after stent planting make the OCT become an efficient tool for cardiovascular disease diagnosis and treatment. This paper presents a novel coronary vessel intimal sequence extraction method based on prior boundary constraints in OCT image. On the basis of conventional Chan-Vese model, we modified the evolutionary weight function to control the evolutionary rate of boundary by adding local information of boundary curve. At the same time, we added the gradient energy term and intimal boundary constraint term based on priori boundary condition to further control the evolutionary of boundary curve. At last, coronary vessel intimal is extracted in a sequence way. The comparison with vessel intimal, manual segmented by clinical scientists (golden standard), indicates that our coronary vessel intimal extraction method is robust to intimal boundary blur, distortion, guide wire shadow and plaque disturbs. The results of this study can be applied to clinical aid diagnosis and precise diagnosis and treatment.
Spontaneous coronary artery dissection in a young man - Case report
Julia Schmid, Johann Auer
Journal of Cardiothoracic Surgery , 2011, DOI: 10.1186/1749-8090-6-22
Abstract: Spontaneous coronary artery dissection (SCAD) is a rare and uncommon case of sudden cardiac death and acute coronary syndrome [1]. As several diseases and conditions have been associated with SCAD it therefore probably constitutes a heterogeneous entity. Risk factors for SCAD comprise pregnancy, Ehlers-Danlos disease, Marfan's Syndrome, intensive exercise, or cocaine abuse [1-4]. The clinical presentation of SCAD depends on the extent and the flow limiting severity of the coronary artery dissection, and ranges from asymptomatic to unstable angina, acute myocardial infarction, ventricular arrhythmias to sudden cardiac death. Coronary angiography is frequently used in the evaluation of patients with acute coronary syndromes. Thus, most cases with SCAD are detected by angiography. Moreover, intracoronary imaging techniques such as intravascular ultrasound (IVUS) and optical coherence tomography (OCT), which provide detailed morphological information on coronary lesions and on the location of dissection planes between the different layers of the arterial wall, have enabled a more detailed clinical assessment of SCAD. Furthermore, non-invasive coronary angiography by multidetector computed tomography (MDCT) has been used for longitudinal follow-up evaluation of patients with SCAD. There is no consensus about the way of treatment including medical therapy, interventional treatment with PCI or surgery. We present a case of SCAD complicated by the occurrence of a left ventricular thrombus in a 31 years old man admitted with an acute coronary syndrome.A 31-year old man was admitted to our intensive care unit with recurrent chest pain over a period of about three weeks. Chest discomfort severely worsened during the 5 hours before hospital admission. At admission the patient had severe chest pain. Physical examination of the chest did not reveal any abnormalities. Blood pressure at admission was 150/85 mmHg and pulse rate was 86 beats per minute. The medical history was remark
Diurnal Choroidal Thickness Changes in Normal Eyes of Turkish People Measured by Spectral Domain Optical Coherence Tomography  [PDF]
Ozen Ayranc? Osmanbasoglu,Zeynep Alkin,Abdullah Ozkaya,Yavuz Ozp?nar,Ahmet Taylan Yazici,Ahmet Demirok
Journal of Ophthalmology , 2013, DOI: 10.1155/2013/687165
Abstract: Purpose. To analyse the diurnal variation of central choroidal thickness (CCT) in healthy emetropic patients during working hours. Methods. Fifty healthy young emmetrpic volunteers were included in this study. CCT was measured at 9?AM and 4?PM with spectral domain optical coherence tomography (Spectralis, Heidelberg Engineering) with enhanced depth imaging. Diurnal variation of CCT, the correlation between rigth and left eyes and the demographic factors affecting this variation were assessed. Findings. The mean CCT at 9?AM and 4?PM was 308.7 ± 64.5?μm and 308.7 ± 62?μm, respectively, with a mean diurnal amplitude of ?0.03 ± 14.7?μm, ranging between ?55?μm and 47?μm, the difference was statistically insignificant ( : 0.9). There were positive correlations between right and left eyes among CCT measurements at 9?AM, 4?PM and the mean amplitude of diurnal change ( : 0.65, ; : 0.60, ; : 0.45, : 0.00, resp.). There was a statistically significant negative correlation between the magnitude of diurnal change and age ( : ?0.27, : 0.01). Conclusion. Although the mean CCT in the all group does not show significant variation during working hours, the pattern of diurnal variation may vary from person to person according to age, and there is a great harmony between the two eyes. 1. Introduction The choroid is the middle vascular layer of the eye, lying between the retina and sclera. It accounts for 85 percent of ocular blood flow and plays a major role in the oxygenation, nourishment, and viability of retinal pigment epithelium and the outer retinal layers, which have the highest metabolic activity. Choroidal changes such as hyperpermeability, vascular insufficiency, thickening, and thinning were shown to play a role in the pathogenesis of chorioretinal disease. With the recent improvements in technology, Spaide et al. [1] developed the enhanced depth imaging (EDI) technique by using spectral-domain optical coherence tomography (OCT), which enables the visualization and measurement of the choroidal layer. Many studies have been published reporting the choroidal thickness (CT) of patients with various retinal disorders such as central serous chorioretinopathy [2–4], age-related macular degeneration [4–8], polypoidal choroidal vasculopathy [7, 8], Vogt-Koyanagi-Harada syndrome [9], and macular hole [10], multiple evanescent white dot syndrome [11] and diabetic retinopathy [12]. Also, the normative data of choroidal thickness of healthy individuals were reported as a guide for further investigations [13–17]. Therefore, OCT is a valuable tool for the diagnosis and
Stenting of Anomalous Left Main Coronary Artery Stenosis in an Adult with a Retroaortic Course  [PDF]
Lanjewar Charan,Santosh Shiradkar,P. G. Kerkar,Agrawal Ashish
Cardiology Research and Practice , 2011, DOI: 10.4061/2011/296946
Abstract: Coronary bypass graft has been the conventional treatment of choice in anomalous left man coronary artery stenosis. We are reporting an interesting case with anomalous left main coronary artery originating from right aortic sinus having retroaortic course complicated by significant atherosclerotic narrowing of the vessel and its percutaneous management. 1. Case Report A 58-year-old diabetic male presented with rest angina followed by syncope. Baseline ECG showed right bundle branch with no significant ST-T changes. However, cardiac troponin was elevated suggesting acute coronary syndrome. Transthoracic Echocardiography was unremarkable with no regional wall motion abnormalities at rest. Cardiac catheterization with coronary angiography demonstrated anomalous origin of single coronary artery from right sinus of valsalva and dividing into left main and right coronary artery. After getting origin, LMCA had long retroaortic course with significant discrete stenosis in the mid-stem of it, dividing finally into left anterior descending artery and left circumflex artery. Etiology of coronary occlusion was atherosclerotic plaque and hence was present throughout cardiac cycle and no dynamic cause could be seen. Computerized tomography coronary angiography confirmed the anomalous left main artery origin and its course (Figure 1). Figure 1: Computerized tomography angiogram. (a) Shows anomalous left main coronary artery (LMCA) arising from the single right coronary cusp and then has the retroaortic course (presenting). Main stem shows significant discrete stenosis. (b) Demonstrates patent stent in anomalous LMCA (after stenting). During intervention anomalous coronary was cannulated with 6F JR guiding catheter (Brite Tip Cordis company) and lesion was crossed with 0.014 angioplasty guide wire (Boston Scientific) and distally parked in the left circumflex artery. To provide the better support, another 0.014?BMW (Balance Middle Weight, Guidant Corporation) guide wire was kept in left anterior descending artery. Direct stenting was performed successfully with 3.5 × 12?mm drug eluting stent (Zotarolimus, Endeavour) at 14?atm (Figure 2). The procedure was uneventful and TIMI 3 flow achieved. The patient is doing very well and is asymptomatic at the recent clinical followup. Figure 2: Coronary angiogram. (a) Anomalous LMCA with significant stenosis and its course. (b) Shows well-deployed stent in LMCA. 2. Discussion Anomalies of the coronary arteries may be found incidentally in 0.3–1% of healthy individuals. Although coronary artery anomalies are far less common than
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