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.     

光学相干断层成像在冠状动脉临界病变介入诊断与治疗中的应用

目的评价光学相干断层成像(optical coherence tomography,OCT)在冠状动脉临界病变介入诊断与治疗中的可行性与有效性。方法在获得患者知情同意后,对来自15例患者的共16处冠状动脉造影结果显示狭窄程度(最小管腔直径/参照管腔直径)介于40%和70%之间的病变(即临界病变)行冠状动脉内OCT检查,评价病变狭窄程度、脂质核心大小、纤维帽的厚度、是否存在斑块破裂、是否伴有血栓形成以及斑块钙化程度。根据检查结果对伴随临床症状和心电图改变的易损斑块进行介入治疗。支架置入术后重复OCT检查,判断支架是否充分覆盖病变、与血管壁贴合情况,是否有斑块组织通过支架网眼突入管腔,以及局部是否存在微小夹层。结果入选的16处病变中的14处成功行OCT检查并获取满意图像。检查结果显示14处病变中有10处病变狭窄程度超过50%,并且脂质核心较大、纤维帽厚度小于65μm,判定以上10处病变为易损斑块,行冠状动脉内支架置入术。对其中2处伴有斑块破裂、局部形成夹层的病变行球囊预扩张后也行OCT检查,可见明显内膜撕裂、夹层形成。10处病变支架置入术后复查OCT显示支架均充分覆盖病变,其中2处支架与血管壁贴合不良,3处发生斑块组织明显突入管腔,有2处支架部分节段释放不充分。其余4处病变脂质核心较小,纤维帽厚度大于65μm,无斑块破裂表现,未行冠状动脉介入治疗。结论冠状动脉内OCT是一种判定冠状动脉病变特征的有效手段,对诊断易损斑块、制定经皮冠状动脉介入治疗策略以及评价支架置入术后即刻效果具有重要意义。     

光学干涉断层成像系统对冠心病病变特征的评价

目的:初步探讨光学干涉断层成像(OCT)系统评价冠心病病变特征的价值。方法:分析在2005年12月行冠状动脉造影检查的同时接受OCT检查的5例冠心病患者的OCT影像特征。结果:2例不稳定型心绞痛患者中,1例右冠状动脉中段成角病变狭窄99%,OCT清晰显示血栓、钙化、纤维帽厚度及脂质斑块,介入治疗后OCT检查示支架贴壁良好,血栓消失;1例前降支狭窄50%,OCT探测到清晰的附壁血栓、最薄处纤维帽及斑块破裂。3例介入治疗后患者中,1例回旋支中远段支架内狭窄75%、2例前降支支架内狭窄50%,OCT检查精确定量再狭窄程度63.33%~87.25%,增生基质主要为纤维样组织,可见少许脂质样基质,其中回旋支支架内狭窄患者OCT检查时发生支架远段冠状动脉夹层,行回旋支远段支架置入术治疗。结论:OCT系统在评价冠心病病变特征和介入治疗结果方面具有较好的应用价值。     

光学相干断层成像在冠心病介入治疗中的应用价值

目的应用光学相干断层成像（OCT）技术评价冠状动脉内粥样硬化斑块、血管对置入支架后即刻和中远期的反应。方法20例冠心病患者,有22支血管在完成冠状动脉造影或介入治疗后进行OCT成像。同时获取23个支架OCT成像,在23个支架中有15个为支架术后4～35个月随访,其中7个为雷帕霉素药物洗脱支架,8个为金属裸支架,另外8个为支架置放后即刻成像。结果入选的20例患者均成功进行OCT检查,并获取22支血管和23个支架满意的图像。通过OCT成像清晰地显示8处纤维斑块、3处钙化斑块、9处富含脂质斑块、2处血栓形成、斑块破裂3处及血管壁上夹层、粥样硬化斑块微小裂口和夹层等。7个置入雷帕霉素药物洗脱支架后OCT随访,均未发现有明显再狭窄,支架表面有少量内膜覆盖,部分支架表面没有内膜覆盖,其中1个支架血管出现瘤样扩张、支架与血管壁分离、支架表面没有内膜覆盖,有1个支架没有充分扩张。8个金属裸支架后用OCT随访发现,所有置入金属裸支架后支架表面内膜增殖明显,其中有3个支架因为内膜过度增殖而出现再狭窄,并再次接受介入治疗。8个支架术后即刻OCT检查显示,与血管贴壁均良好、支架扩张充分有3个支架,4个支架充分扩张,但可见到斑块裂片通过支架网眼突入管腔,1个支架支撑杆分布不均,可见支架与血管壁分离,在8个支架中有2个为支架内套叠支架。结论OCT成像技术可清晰显示各种冠状动脉粥样斑块情况,并可用于评价冠状动脉介入治疗的效果。     

光学相干断层成像在经皮冠状动脉介入治疗前后的应用

目的:探讨光学相干断层成像(OCT)在经皮冠状动脉介入治疗(PCI)前后应用的指导作用。方法:入选40例于我院行冠状动脉造影患者,根据罪犯血管狭窄程度分为两组:A组(狭窄程度≤75%,n=20)冠状动脉造影后行OCT检查,观察有无富含脂质斑块、薄帽纤维粥样斑块、斑块破裂、血栓,并测定病变狭窄程度;如需置入支架,则在术后即刻复查OCT,观察有无支架杆贴壁不良、血管夹层、组织脱垂等。B组(狭窄程度75%,n=20)仅在支架置入术后即刻行OCT检查。结果:A组20例患者的20支罪犯血管中,15支(75%)病变狭窄程度70%,其中3支为支架内再狭窄,6支血管发现斑块破裂,3支血管发现血栓形成,共发现富含脂质斑块22处、薄帽纤维粥样斑块9处(平均纤维帽厚度0.06 mm);共置入支架19枚,术后即刻行OCT检查,13枚支架(68.4%)可见不同程度的组织脱垂,平均最大组织脱垂面积为0.16±0.05(0.09~0.21)mm2,4枚支架(21.1%)中8个支架杆贴壁不良。B组20例患者的20支罪犯血管共置入34枚药物洗脱支架,术后即刻行OCT检查,有28枚支架(82.4%)存在不同程度的组织脱垂,平均最大组织脱垂面积为0.40±0.31(0.06~1.02)mm2。有9枚支架(26.5%)共20个支架杆贴壁不良。所有患者随访6个月以上,未发生严重心脏缺血事件。结论:OCT技术在支架术前可清晰显示冠状动脉结构、辨别不同斑块、斑块破裂及血栓,精确测量管腔狭窄程度。在支架术后可清晰显示血管夹层,组织脱垂及支架杆贴壁情况,可以指导及评价介入治疗。     

应用光学相干断层成像(OCT)评价冠状动脉内支架置入后的内膜覆盖

在冠状动脉介入治疗发展三十多年的今天,有许多新兴的技术来弥补冠状动脉造影的局限性,其中最具代表性的是血管内超声(IVUS)技术.IVUS不仅对判断冠状动脉病变程度、斑块是否稳定、管腔大小、是否需要介入治疗有重要参考价值,也是判断介入后支架是否贴壁良好、病变覆盖程度、是否有撕裂的主要手段,目前在全世界范围内广泛使用.冠状动脉内血管镜用来评价血管内膜对支架的覆盖程度、是否存在血栓.目前在日本的一些医院应用.自2001年开始国外首次报道光学相干断层成像(OCT)技术在人体冠状动脉内获得高清晰图像以来,OCT技术在冠心病介入领域中应用报道逐渐增多,目前备受国内外专家的高度关注.     

光学相干断层扫描评价糖尿病冠心病患者冠脉病变的进展

糖尿病可促进血管内膜增生,易损斑块破裂,血栓形成,支架边缘夹层等。光学相干断层扫描（OCT）是目前最先进的血管内成像技术,临床主要用于识别冠状动脉易损斑块和药物洗脱支架（DES）置入术后随访。该文主要介绍OCT评估糖尿病冠心病患者冠状动脉病变特点。     

光学相干断层成像对ST段抬高型心肌梗死患者急诊经皮冠状动脉介入治疗策略的影响

目的探讨光学相干断层成像(OCT)指导下对急性ST段抬高型心肌梗死(STEMI)急诊经皮冠状动脉介入治疗(PCI)策略的影响。方法纳入2016年1月至2017年5月接受急诊PCI并行OCT检查的STEMI患者100例,利用OCT检查明确STEMI发病机制,评价PCI即刻效果,随访12个月观察预后。结果 17例(17.0%)患者因OCT图像欠清晰未能明确心肌梗死发病机制,其中15例置入支架;其余83例患者中斑块破裂54例(65.1%,54/83)、斑块侵蚀22例(26.5%,22/83)、钙化结节2例(2.4%,2/83)、支架贴壁不良致晚期支架内血栓形成2例(2.4%,2/83)、亚急性支架内血栓形成1例(1.2%,1/83)、冠状动脉痉挛2例(2.4%,2/83),其中68例置入支架。83例置入支架、造影成功的患者中,OCT发现支架术后造影不易识别的支架贴壁不良、组织脱垂、支架膨胀不全患者18例(21.7%,18/83);支架边缘夹层16例(19.3%,16/83),其中血流受限需要干预的支架近端夹层2例(2.4%,2/83)。17例未置入支架患者中冠状动脉痉挛2例、血栓负荷重1例,其余14例(斑块破裂7例、斑块侵蚀4例、晚期支架内血栓形成2例及亚急性支架内血栓形成1例)因OCT检查残余狭窄70%、TIMI血流Ⅲ级未置入支架。随访(11.0±4.0)个月,除1例院内死于心源性休克和1例亚急性支架内血栓形成患者外,所有出院患者均未发生主要不良心血管事件。结论 OCT可以检测出约1/4 STEMI患者冠状动脉支架置入术后多种不良特征并进行治疗。     

血管内超声在冠状动脉病变诊断及治疗中的应用价值

目的 探讨血管内超声(IVUS)检查在轻中度冠脉病变诊断及治疗中的价值。方法 对56例临床诊断为冠心病(CHD)的患者行冠状动脉造影(CAG)及IVUS检查。结果 ①56例共83处血管段,CAG示钙化性斑块12处,IVUS示钙化性斑块42处(P<0.01)。CAG示偏心性斑块25处,IVUS示偏心性斑块58处(P<0.01)。CAG示面积狭窄率为(55.09％±6.74％),IVUS示面积狭窄率为(72.00％±5.87%),P<0.05。②IVUS与CAG示面积狭窄程度呈正相关(r=0.63,P<0.01)。③CAG显示56例83处血管段均未达到支架置入指征,IVUS检测43处血管段需置入支架。④CAG显示43处血管段手术效果均理想,IVUS显示5例内膜撕裂严重者需进一步处理。结论 IVUS对于冠状动脉轻中度的诊断和介入治疗有较高的价值,且优于CAG。     

FD-OCT在急性冠状动脉综合征介入诊治中的应用研究

目的:评价第2代频域光学相干断层成像(FD-OCT)技术在急性冠状动脉综合征(ACS)介入诊断及治疗的价值及安全性。方法:随机入选ACS患者23例,在冠状动脉(冠脉)造影后进行FD-OCT成像,评价冠脉血管的病变情况,指导冠脉介入治疗(PCI),并在患者支架植入后即刻,用OCT成像系统评价支架释放的情况。结果:23例ACS患者中,不稳定型心绞痛5例,非ST段抬高性心肌梗死12例,ST段抬高性心肌梗死6例;其中5例单纯冠脉造影,1例冠脉内球囊扩张(PTCA),17例行支架植入术;共植入支架28枚,2例为再次支架植入;2例为左主干病变,3例为分叉病变;23例患者30支血管行FD-OCT成像,无严重不良反应。发现斑块破裂16处,纤维斑块10处,脂质斑块16处,易损斑块13处,支架5枚贴壁不良,冠脉内血栓6例,支架内再狭窄2例,支架扩张不全3例,内膜过度增生1例,支架边缘撕裂夹层1处。结论:FD-OCT在ACS患者中应用有良好的操作性及安全性。FD-OCT可清晰显示各种冠脉病变的情况,特别是易损斑块、血栓及支架贴壁情况,可用于指导及评价PCI,弥补冠脉造影的不足。     

Assessment of coronary plaque with optical coherence tomography and high-frequency ultrasound

This study compares the ability of intravascular optical coherence tomography (OCT) and high-frequency intravascular ultrasound (IVUS) to image highly stenotic human coronary arteries in vitro. Current imaging modalities have insufficient resolution to perform risk stratification based on coronary plaque morphology. OCT is a new technology capable of imaging at a resolution of 5 to 20 microm, which has demonstrated the potential for coronary arterial imaging in prior experiments. Human postmortem coronary arteries with severely stenotic segments were imaged with catheter-based OCT and IVUS. The OCT system had an axial resolution of 20 microm and a transverse resolution of 30 microm. OCT was able to penetrate and image near-occlusive coronary plaques. Compared with IVUS, these OCT images demonstrated superior delineation of vessel layers and lack of ring-down artifact, leading to clearer visualization of the vessel plaque and intima. Histology confirmed the accuracy and high contrast of vessel layer boundaries seen on OCT images. Thus, catheter-based OCT systems are able to image near-occlusive coronary plaques with higher resolution than that of IVUS.     

Porcine coronary imaging in vivo by optical coherence tomography

OBJECTIVE: A high-resolution coronary artery imaging modality has the potential to address important diagnostic and management problems in cardiology. Optical coherence tomography (OCT) is a promising new optical imaging technique with a resolution of approximately 10 microm. The purpose of this study was to use a new OCT catheter to demonstrate the feasibility of performing OCT imaging of normal coronary arteries, intimal dissections, and deployed stents in vivo. METHODS AND RESULTS: Normal coronary arteries, intimal dissections, and stents were imaged in five swine with OCT and compared with intravascular ultrasound (IVUS). In the normal coronary arteries, visualization of all of the layers of the vessel wall was achieved with a saline flush, including the intima which was not identified by IVUS. Following dissection, detailed layered structures including intimal flaps, intimal defects, and disruption of the medial wall were visualized by OCT. IVUS failed to show clear evidence of intimal and medial disruption. Finally, the microanatomic relationships between stents and the vessel walls were clearly identified only by OCT. CONCLUSIONS: In this preliminary experiment, we have demonstrated that in vivo OCT imaging of normal coronary arteries, intimal dissections, and deployed stents is feasible, and allows identification of clinically relevant coronary artery morphology with high-resolution and contrast.     

Utility of optical coherence tomography and intravascular ultrasound for the evaluation of coronary lesions

Optical coherence tomography (OCT) and intravascular ultrasound (IVUS) are imaging methods used in the diagnosis of coronary lesions. IVUS is widely used in interventional cardiology laboratories, but OCT is now increasingly used. Conventional coronary angiography can identify different types of coronary lesions but sometimes is unable to diagnose them correctly. Both intravascular imaging methods are useful for better interpretation of these lesions, and can accurately diagnose ruptured plaques, thrombosis, stent restenosis and hazy images. However, the resolution of OCT is ten times higher than IVUS, and so an accurate diagnosis cannot always be achieved with ultrasound imaging. We present three cases in which IVUS was unable to identify the lesion causing the condition and OCT was required to obtain clearer images that helped to confirm the diagnosis. The advantages and disadvantages of each method are then discussed.     

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.     

Visualization of coronary atherosclerotic plaques in patients using optical coherence tomography: comparison with intravascular ultrasound

OBJECTIVES: The aim of this study was to evaluate the feasibility and the ability of intravascular optical coherence tomography (OCT) to visualize the components of coronary plaques in living patients. BACKGROUND: Disruption of a vulnerable coronary plaque with subsequent thrombosis is currently recognized as the primary mechanism for acute myocardial infarction. Although such plaques are considered to have a thin fibrous cap overlying a lipid pool, imaging modalities in current clinical practice do not have sufficient resolution to identify thin (< 65 microm) fibrous caps. Optical coherence tomography is a new imaging modality capable of obtaining cross-sectional images of coronary vessels at a resolution of approximately 10 microm. METHODS: The OCT images and corresponding histology of 42 coronary plaques were compared to establish OCT criteria for different types of plaques. Atherosclerotic lesions with mild to moderate stenosis were identified on angiograms in 10 patients undergoing cardiac catheterization. Optical coherence tomography and intravascular ultrasound (IVUS) images of these sites were obtained in all patients without complication. RESULTS: Comparison between OCT and histology demonstrated that lipid-rich plaques and fibrous plaques have distinct OCT characteristics. A total of 17 IVUS and OCT image pairs obtained from patients were compared. Axial resolution measured 13 +/- 3 microm with OCT and 98 +/- 19 microm with IVUS. All fibrous plaques, macrocalcifications and echolucent regions identified by IVUS were visualized in corresponding OCT images. Intimal hyperplasia and echolucent regions, which may correspond to lipid pools, were identified more frequently by OCT than by IVUS. CONCLUSIONS: Intracoronary OCT appears to be feasible and safe. Optical coherence tomography identified most architectural features detected by IVUS and may provide additional detailed structural information.     

Safety and feasibility of an intravascular optical coherence tomography image wire system in the clinical setting

Optical coherence tomography (OCT) is a fiber-optic technology that enables high-resolution intracoronary imaging. The aim of this study was to evaluate the safety and feasibility of intracoronary imaging with OCT in the clinical setting; 76 patients with coronary artery disease from 8 centers were enrolled. The OCT imaging system (ImageWire, Light Imaging Inc., Westford, Massachusetts) consists of a 0.006 inch fiber-optic core that rotates within a 0.016 inch transparent sheath. OCT imaging was performed during occlusion of the artery with a compliant balloon and continuous flushing. Intravascular ultrasound (IVUS) imaging was performed in the same segments. We assessed the safety and feasibility of the OCT imaging, compared with IVUS. Vessel occlusion time was 48.3 +/- 13.5 seconds and occlusion-balloon pressure was 0.4 +/- 0.1 atmospheres. Flushing with lactated Ringer's solution was performed at a rate of 0.6 +/- 0.4 ml/s. No significant adverse events, including vessel dissection or fatal arrhythmia, were observed. Procedural success rates were 97.3% by OCT and 94.5% by IVUS. The OCT image wire was able to cross 5 of 6 tight lesions that the IVUS catheter was unable to cross. Of the 98 lesions in which both OCT and IVUS were successfully performed, OCT imaging had an advantage over IVUS for visualization of the lumen border. Minimum lumen diameter and area measurements were significantly correlated between OCT and IVUS imaging (r = 0.91, p <0.0001 and r = 0.95, p <0.0001, respectively). In conclusion, this multicenter study demonstrates the safety and feasibility of OCT imaging in the clinical setting.     

Intravascular Ultrasound Assessment of the Mechanisms and Predictors of Restenosis Following Coronary Angioplasty

Restenosis occurs after 30% to 50% of transcatheter coronary procedures; its mechanisms remain incompletely understood. Intravascular ultrasound (IVUS) studies were analyzed in 360 non-stented native coronary artery lesions in which follow-up quantitative angiographic and/or IVUS data was available. Pre-intervention, post-intervention, and follow-up, the external elastic membrane (EEM) and lumen cross-sectional areas (CSA) were measured; plaque + media (P + M = EEM - lumen CSA), and cross-sectional narrowing (CSN = P + M/EEM CSA) were calculated. The anatomic slice selected for serial analysis had an axial location within the lesion at the smallest follow-up lumen CSA. At follow-up, 73% of the decrease in lumen CSA was due to a decrease in EEM CSA; 27% was due to an increase in P+M CSA. The change in lumen CSA correlated more strongly with the change in EEM CSA than with the change in P + M CSA. The change in EEM CSA was bidirectional; 47 lesions (22%) showed an increase in EEM CSA. Despite a greater increase in P + M CSA, lesions exhibiting an increase in EEM CSA had (1) no change in lumen CSA, (2) decreased restenosis, and (3) a 49% frequency of late lumen gain. The independent clinical, angiographic, and IVUS predictors of angiographic restenosis (3 50% diameter stenosis at follow-up) were the IVUS reference lumen CSA, angiographic pre-intervention diameter stenosis, and post-intervention IVUS CSN. Restenosis appeared to be determined primarily by the direction and magnitude of the change in EEM CSA. An increase in EEM CSA was adaptive while a decrease in EEM CSA contributed to restenosis. The most powerful predictor of restenosis was the IVUS post-procedural CSN. The importance of the post-procedural CSN was related to the change in EEM CSA as a mechanism of restenosis.     

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。     

Intracoronary ultrasound assessment late after the arterial switch operation for transposition of the great arteries

OBJECTIVES: This research was undertaken to assess the status of the coronary wall morphology late after the arterial switch operation (ASO) for transposition of the great arteries employing intravascular ultrasound (IVUS). BACKGROUND: Long-term patency of the reimplanted coronary arteries is a key issue after ASO. Follow-up studies have demonstrated coronary obstruction in up to 8% of patients that may be related to progressive fibrocellular intimal thickening. METHODS: Twenty-two asymptomatic children were enrolled at a median age of 9.5 years (range 5 to 22 years); IVUS images were obtained in 20 children at cardiac catheterization 5.0 to 21.6 years after the operation (in two cases IVUS study was not feasible due to technical constraints). Quantitative analysis was performed in 37 coronary arteries involving segments with a mean length of 28.4 +/- 1.8 mm. RESULTS: Thirty-three arteries (89%) displayed variable degrees of proximal eccentric intimal proliferation, with the maximal intimal thickening being 0.26 +/- 0.14 mm (range 0.06 to 0.71 mm) at the most thickened site. According to the Stanford classification, all children had coronary artery involvement with 50% having moderate-to-severe lesions (>0.3 mm). No risk factors for such abnormalities were encountered, including age, origin of the coronary arteries, hemodynamics, and follow-up duration after surgery. CONCLUSIONS: Intravascular ultrasound assessment late after the ASO revealed proximal eccentric intimal thickening in most of the studied vessels. This observation suggests the development of early atherosclerosis in the reimplanted coronary arteries, which may have a role in the genesis of late coronary events.