256层 CT 冠状动脉成像对冠状动脉桥血管的诊断价值

目的：探讨256层CT冠状动脉成像对冠状动脉搭桥术后桥血管的诊断价值。方法收集冠状动脉搭桥术后行256层CT 冠状动脉成像检查29例,回顾性分析256层 CT 冠状动脉成像桥血管的情况。结果29例搭桥血管共77支,搭桥血管1支6例,2支6例,3支10例,4支6例,5支1例,平均2.75支。59支(76.62%)桥血管通畅,17支(22.08%)桥血管管腔狭窄,1支(1.30%)桥血管闭塞。内乳动脉桥6支,大隐静脉桥71支;6支内乳动脉桥中,5支(83.33%)桥血管通畅,1支(16.67%)桥血管管腔狭窄;71支大隐静脉桥中,54支(76.06%)桥血管通畅,16支(22.54%)管腔狭窄,1支(1.40%)管腔闭塞。大隐静脉与内乳动脉桥血管狭窄、闭塞的发生率差异没有显著意义(P >0.05)。结论256层 CT 冠状动脉成像对冠状动脉搭桥术后桥血管的评价有较高的诊断价值,是一种简便、快速、无创、准确、安全的检查方法。     

Sixty four multi-detectors CT coronary angiography: An easy and accurate method to detect graft patency post CABG

Objective

To assess the accuracy of coronary CTA in detection of coronary artery bypass graft patency, occlusion and stenosis.

Patients and methods

Twenty-four patients with past history of coronary bypass surgery were included in this study and underwent MDCT coronary angiography. Invasive coronary angiography was done within 2 weeks of MDCT coronary angiography. All grafts considered patent were then evaluated for the presence of significant stenosis. Significant stenosis was defined as reduction in diameter of more than 50%.

Results

All the MDCT scans were interpretable and a total number of 78 CABG conduits were analyzed. At MDCT angiography 4 (5.2%) grafts were classified as occluded and 74 (94.8%) grafts were patent. Significant stenosis was detected in 7 (9.4%) out of the 74 patent grafts. At invasive coronary angiography; when occlusion and significant stenosis pooled together they were 9 grafts; 4 arterial and 5 venous. All these 9 grafts were detected at MSCT (sensitivity is 100%). In 67 out of 69 grafts occlusion or significant stenosis was correctly ruled out (specificity 97.1%). The diagnostic accuracy of MDCT angiography when compared with invasive angiography was 97.4%. The negative predictive value was 100% and positive predictive value was 81.8%.

Conclusion

MDCT coronary angiography is an accurate imaging technique for the evaluation of CABG patency and in detection of graft stenosis and confirms of previous studies using 64 MDCT.     

Coronary artery bypass graft imaging using ECG-gated multislice computed tomography: comparison with catheter angiography

AIM: To compare the value of multislice computerized tomography (MSCT) in imaging coronary artery bypass grafts (CABGs) by direct quantitative comparison with standard invasive angiography. METHODS: Using MSCT, 50 consecutive patients who had previously undergone CABG surgery and had recently undergone invasive angiography for recurrent angina pectoris, were studied further using MSCT after intravenous injection of non-ionic contrast agent; cardiac imaging was performed during a single breath-hold. Graft anatomy was quantified, using both quantitative coronary angiography (QCA) and MSCT, by different investigators blinded to each other. Reproducibility was quantified using the standard error of the measurement expressed as a percentage in log-transformed values (CV%) and intraclass correlation (ICC). RESULTS: All 150 grafts were imaged using MSCT; only 4 patent grafts were not imaged using selective angiography. Good agreement was achieved between MSCT and QCA on assessment of proximal anastomoses (CV% 25.2, ICC 0.84), mid-vessel luminal diameter (CV% 15.5, ICC 0.91) and aneurysmal dilations (CV% 14.3). Reasonable agreement was reached on assessment of distal anastomoses (CV% 26.7, ICC 0.66) and categorization of distal run-off (ICC 0.73). Good agreement was observed for stenoses of over 50% luminal loss (CV% 8.7, ICC 0.97) but agreement on assessment of less severe lesions was poor (CV% 208.7, ICC 0.51). CONCLUSION: This study demonstrates that CABGs can be quantitatively evaluated using MSCT, and that significant lesions present in all CABG segments can be reliably identified. Agreement between MSCT and QCA for lesions of less than 50% luminal loss was poor.     

Non-invasive evaluation of coronary artery stent patency with retrospectively ECG-gated 64-slice CT angiography

The aim of our study has been to evaluate the ability of 64-slice computed tomographic angiography (CTA) to assess coronary artery stent patency, relative to selective coronary angiography (SCA). Fifty-five consecutive patients (age range 45–80 years) with 97 previously implanted coronary artery stents underwent 64-slice CTA. The 55 patients comprised 40 subjects (group A) who were referred for follow-up SCA at a mean interval of 9.6 months after stent positioning, and 15 subjects (group B) in whom SCA was clinically indicated. Stent evaluation was performed independently by two blinded readers in terms of image quality and presence of in-stent restenosis (ISR; lumen obstruction of ≥50%). SCA was performed in 41/55 patients; 14 patients refused to undergo SCA after the 64-slice CTA exam. A total of 88 stents in 74 segments were analyzed. Twenty-one of the 74 stented segments were of poor image quality and were not considered for further analysis. Sixty-four-slice CTA detected 12/16 ISR (sensitivity: 75%) and ruled out ISR in 32/37 cases (specificity: 86%). Sixty-four-slice CTA is a valuable modality for follow-up of coronary artery stent patency only in selected patients. Appropriate candidates for follow-up 64-slice CTA should be established based on stent diameter, stent material and type as well as HR and heart rhythm. However, given the number of non-assessable segments, further work would appear necessary before 64-slice CTA can be considered a suitable procedure for broad clinical application in the evaluation of coronary artery stent patency.     

Aortic dissection following coronary artery bypass surgery: Diagnosis by CT

We describe an unusual case of aortic dissection causing spinal cord infarction. The dissection arose from an intimal tear at the suture line of a coronary artery bypass graft. CT was used to diagnose the dissection and to demonstrate its extension to the aortoiliac bifurcation and innominate artery and its rupture into the left pleural cavity. The most common causes of intimal tears following cardiac bypass surgery are aortic cross-clamping, aortic cannulation, and injury during suturing of the graft to the aorta. An underlying disease of the aorta such as atherosclerosis, cystic medial necrosis, or aortitis is commonly present. CT is an accurate and safe means of detecting aortic dissections following cardiac surgery, and is also useful in assessing the extent of the dissection and identifying its rupture into the pleural or pericardial cavity.     

基于人工智能的冠状动脉CT血管成像检测阻塞性冠状动脉狭窄效能的研究

目的 以有创冠状动脉造影（ICA）为参考标准,探讨人工智能(AI)辅助的冠状动脉CT血管成像（CCTA）诊断阻塞性冠状动脉狭窄的效能。 方法 回顾性收集行CCTA检查并于3个月内行ICA检查的50例疑患冠状动脉疾病（CAD）的病人,男34例,女16例,平均年龄（61.8±8.5）岁。AI软件、不同年资医师（低/中/高年资）及AI+不同年资医师分别对入组病人CCTA影像进行后处理并解读。将ICA和CCTA上冠状动脉管腔狭窄≥50%定义为阻塞性冠状动脉狭窄。采用Agatston积分法测量病人的钙化积分值,并将病人分为低钙化组（钙化积分<100）和高钙化组（钙化积分≥100）。采用独立样本t检验对AI、医师及AI+医师的图像后处理和解读时间进行两两比较。以ICA为参考标准,分析AI在不同研究水平和高/低钙化组的诊断价值,并比较AI、不同年资医师和AI+不同年资医师的诊断敏感度、特异度、阳性预测值、阴性预测值、准确度及受试者操作特征（ROC）曲线下面积（AUC）。采用Pearson卡方检验或Fisher精确概率检验比较组间差异,采用DeLong检验比较AUC。 结果 50例病人共分析195支血管424个节段。AI和AI+医师的平均后处理和解读时间均低于单独医师诊断的时间（均P<0.05）,AI的时间较低/中/高年资医师分别减少了80%、76.8%和75%;AI+低/中/高年资医师较单独医师分别减少了67%、64%、57.9%。在病人、血管及节段水平,AI诊断阻塞性冠状动脉狭窄的敏感度分别为93.7%、83.1%、67.7%,特异度为50.0%、89.0%、91.0%,准确度为92%、86.7%、85.6%,阳性预测值为97.8%、83.1%、69.8%,阴性预测值为25%、89.0%、90.2%,AUC为0.87、0.89、0.83;在血管及节段水平,AI对低钙化组的特异度高于高钙化组（均P<0.05）。在血管水平,AI诊断的AUC值均低于中/高年资医师（均P<0.05）;其余研究水平,AI与其他不同年资医师诊断的AUC值差异均无统计学意义（均P>0.05）。3种研究水平下,AI+低/中/高年资医师诊断的AUC值与单独不同年资医师诊断的AUC值差异均无统计学意义（均P>0.05）。 结论 AI辅助的CCTA诊断阻塞性冠状动脉狭窄具有较好的诊断效能,且明显缩短后处理时间,可能成为临床医师诊断阻塞性冠状动脉狭窄的有效辅助工具。     

Post-mortem cast angiography in the diagnostics of graft complications in patients with fatal outcome following coronary artery bypass grafting (CABG)

The advantages and limitations of a novel post-mortem angiographic method using solidifying silicone rubber and lead oxide as a contrast medium in detecting coronary artery graft complications on a routine basis were evaluated in a series of 223 consecutive patients with fatal outcome within 30 days following coronary artery bypass grafting (CABG). Of these patients, 166 (74.4%) were male and 57 (25.6%) female (mean age 61.9 ± 9). Coronary grafts totalled 660 (3.0 per patient) with 517 aortic and 838 coronary anastomoses. At autopsy, the rubber cast model of the grafts and coronary arterial tree was exposed by a bend scalpel and sites of possible complications were examined. Post-mortem angiographs were re-evaluated and compared with preoperative angiographs and dissection findings. By combining the findings of angiography and heart dissection, 122 (54.7%) of the 223 patients were found to have some type of complication of the graft or the anastomosis. The diagnostic sensitivity and specificity of postmortem angiography was 100% in assessing narrowing or twisting of the graft as well as narrowing of the aortal anastomosis, whereas these findings were revealed with difficulty by autopsy dissection only. In cases with correct x-ray projection, narrowing and occlusion of the proximal aortal and distal coronary anastomosis were also reliably revealed by angiography. In contrast, graft thrombosis was clearly overdiagnosed by angiography, leading to a lower specificity (84%) but high sensitivity (100%) in detecting this complication. Post-mortem angiography also failed to detect dissection of the wall of the graft or anastomosis. Technical problems with this angiographic method were due to too low perfusion pressure, too rapid polymerizing of the silicone rubber, leakage of contrast medium into the ventricles, or faulty x-ray projections. These results suggest that our post-mortem angiographic technique, yielding a permanent rubber- cast model of the graft and anastomosis site, improves the accuracy of diagnostics of postoperative CABG complications and eases postoperative autopsy dissection, which can now be directed to confirm suspected complications. Received: 27 October 1997 / Received in revised form: 2 July 1998     

16层螺旋CT冠状动脉成像的技术与应用

目的:探讨多层螺旋CT冠状动脉造影(multislice spiral CT coromary angiography,MSCTCA)的成像技术和临床应用价值。方法:37例患者行MSCTCA检查,利用多种方法进行重建,分析影响冠状动脉图像质量的重要因素,MSCTCA对冠状动脉的显示能力,冠状动脉狭窄程度的评价,冠状动脉斑块性质的判断,冠状动脉的解剖变异,并了解桥血管和支架的通畅性。结果:容积再现图像最佳的显示相位窗为75%,左主干、左前降支重建的最佳相位为75%,右冠和左回旋支为50%~70%。MSCTCA能显示的管腔最小径1.5mm。对冠状动脉的解剖变异、冠状动脉狭窄的程度、斑块的性质及桥血管和内支架显示良好。结论:MSCTCA可作为冠心病介入治疗前的筛选,能能评价斑块的性质,在血运重建后的复查中也有很高的应用价值,并能提供冠状动脉其他病变的信息。     

动态容积320排冠状动脉CT血管成像诊断冠状动脉疾病的意义

目的：研究320排动态容积冠状动脉CT成像（CCTA）诊断冠状动脉疾病（CAD）的可行性。方法：5961例临床诊断CAD的患者进行CCTA检查,其中186例接受常规X线冠状动脉造影术（CAG）,对照分析其检查结果。1490例接受CCTA检查的健康查体者作为对照。结果：成像质量均在I～III级,无呼吸伪影图像。在186例CAD患者中,CCTA诊断冠状动脉狭窄（狭窄度≥50％）的敏感性为96．72％,特异性98．95％,阳性预测值95．16％,阴性预测值99．30％,准确度98．56％。结论：320排动态容积CT冠状动脉成像图像清晰,对诊断CAD具有重要的临床价值。     

双源CT血管成像对冠状动脉瘘的诊断价值

目的 探讨双源CT血管成像(DSCTA)在先天性冠状动脉瘘(CAF)诊断中的应用价值.方法 分析68例接受回顾性心电门控冠状动脉DSCTA的CAF患者影像资料,进行容积再现(VR)、多平面重建(MPR)、最大密发投影(MIP)、曲面重建(CPR)后确定诊断.结果 68例CAF中,瘘口位于肺动脉18例,右心室31例,左心室16例,上控静脉3例;CAF瘘支血管起源右冠状动脉33例,左冠状动脉30例,左、右冠状动脉双侧起源5例.瘘支血管影像表现为增宽、迂曲28例,扩张、动脉瘤26例,迂曲的血管网18例.结论 冠状动脉DSCTA方便、快捷、无创,可以作为诊断先天性冠状动脉瘘的首选方法.     

Intraindividual comparison of 3D coronary MR angiography and coronary CT angiography

RATIONALE AND OBJECTIVES: To compare the diagnostic value of magnetic resonance (MR) and computed tomography (CT) for the detection of coronary artery disease (CAD) with special regard to calcifications. MATERIALS AND METHODS: Twenty-seven patients with known CAD were examined with a targeted, navigator-gated, free-breathing, steady-state free precession MR angiography sequence (repetition time = 5.6 milliseconds, echo time = 2.8 milliseconds, flip angle 110 degrees ) and 16-slice coronary CT angiography. Segment-based sensitivity, specificity, and accuracy for the detection of stenoses larger than 50% were determined as defined by the gold standard catheter coronary angiography along with the subjective image quality (Grade 1-4). The degree of calcifications in each segment was quantified using a standard calcium scoring tool. RESULTS: Of 115 possible segments, 7% had to be excluded in MR imaging because of poor image quality. In CT, 3% were nondiagnostic because of image quality and 15% were not evaluable because of calcifications. Values for the detection of relevant coronary artery stenoses in the evaluated segments were: sensitivity: MR imaging 85% versus CT 96%; specificity: 88% versus 96%; accuracy: 87% versus. 96%. Average subjective image quality was 1.8 for MR imaging and 1.6 for CT. Of the 15% of segments that had to be excluded from CT evaluation because of calcifications, MR imaging provided the correct diagnosis segments in 67%. CONCLUSIONS: CT provided a better image quality with superior accuracy for the detection of CAD. Despite its overall inferiority, MR imaging proved to be helpful method in interpreting coronary stenosis in severely calcified segments.     

FFR CT诊断冠心病的初步应用体会

目的初步探究基于CT血管成像的无创血流储备分数（FFR_CT）与传统有创血流储备分数（FFR）相比在冠心病病人心肌缺血诊断方面的应用价值。方法纳入2017年2月-12月于我院接受冠状动脉CT血管成像（CCTA）检查且后续1周内完成冠状动脉造影（ICA）及FFR检查的可疑或确诊冠心病的病人20例,其中男13例,女7例,平均年龄（64.72±8.01）岁。对病人CCTA影像采用简化一维cFFR软件进行FFR_CT值测定,以有创性FFR结果作为金标准,分析比较FFR_CT对冠心病病人心肌缺血诊断的敏感度、特异度、阳性预测值、阴性预测值、准确度。绘制受试者操作特征（ROC）曲线,比较FFR_CT与CCTA的诊断准确性。采用Pearson相关性检验及Bland-Altman方法比较FFR_CT与FFR的诊断相关性及一致性。结果以病变为分析单位,FFR_CT与CCTA诊断敏感度、特异度、阳性预测值、阴性预测值、准确度分别为93.5%、86.2%、87.9%、92.6%、90.0%及83.9%、79.3%、82.1%、81.2%、81.7%。FFR_CT和CCTA的ROC曲线下面积分别为0.960及0.892。FFR_CT与FFR诊断一致性及相关性良好（r=0.973,P<0.001）。结论FFR_CT对于冠心病病人心肌缺血诊断具有良好的临床应用价值。     

双源CT血管造影评价冠状动脉狭窄的临床价值

目的:评价双源CT定量诊断冠状动脉狭窄的准确性及临床价值。方法:对30例临床拟诊冠心病患者分别进行双源CT和传统冠状动脉造影检查,并将双源CT判定冠状动脉狭窄程度与冠脉造影结果进行对比分析。结果:30例共计450冠脉节段,双源CT均获得满意的评价图像(3例进行心电编辑)。双源CT判定轻度狭窄38个节段,中度狭窄23个节段,重度狭窄36个节段;与冠状动脉造影结果对比,双源CT诊断冠脉狭窄的敏感性、特异性和准确性分别为94.12%、95.34%和95.11%。结论:与冠状动脉造影对比,双源CT在定量诊断冠脉狭窄方面具有较高的敏感性和特异性,可为临床诊断冠心病提供一项准确可靠的无创手段。     

Influence of intra-coronary enhancement on diagnostic accuracy with 64-slice CT coronary angiography

We assessed the effect of intra-coronary attenuation on diagnostic accuracy using 64-slice computed tomography coronary angiography (CT-CA). We enrolled 170 patients with suspected coronary artery disease who underwent conventional coronary angiography (CA) and 64-slice CT-CA (100 ml of Iomeprol 400 mg I/ml at 4 ml/s). The study population was divided into two groups (85 patients each based on median attenuation of 326 HU) based on mean arterial attenuation; group 1 with low attenuation and group 2 with high attenuation. Diagnostic accuracy for the detection of significant coronary artery stenosis was determined for both groups using CA as reference standard. Overall, 163 significant stenoses were detected in 1,030 assessable coronary artery segments in group 1 compared with 160 significant stenoses in 1,020 assessable segments in group 2. The average intra-coronary attenuation was significantly (P < 0.05) higher for group 2 (388 ± 46 HU) compared with group 1 (291 ± 33 HU). The corresponding sensitivity and specificity values for detection of significant coronary artery stenosis were higher for group 2 (96.3% and 97.6%, respectively) than for group 1 (82.8% and 93.2%, respectively) and were more marked in distal coronary segments than in proximal segments. Higher intra-coronary attenuation on CT-CA results in greater diagnostic accuracy for detection of coronary artery stenosis.     

64层CT血管成像在冠状动脉弹性研究中的价值

目的：评价64层螺旋CT血管成像在测量和计算冠状动脉相关弹性参数中的价值。方法：选取2008年9月-2009年10月本院行冠状动脉CT血管成像检查患者资料共86例,通过测量冠状动脉344节段在收缩期、舒张期的动脉管径变化,分析冠状动脉各段相关动脉弹性参数及其与脉压及平均动脉压的相关性,分析冠状动脉顺应性与收缩压的相关性,包括左主干、左前降支、左回旋支及右冠状动脉。结果：冠状动脉各支血管顺应性参数间存在差别,Friedman T检验,P=0.001,冠状动脉各支血管顺应性与脉压及平均动脉压呈负相关,其余冠状动脉弹性相关参数与脉压及平均动脉压相关性较差;冠状动脉顺应性与收缩压呈负相关（P〈0.05）。结论：64层螺旋CT血管成像可作为一种冠状动脉管腔测量的有效方法,冠状动脉顺应性可较好反映正常冠状动脉血管壁弹性。     

冠状动脉钙化超高速CT检查及与冠状动脉造影的对比研究

目的：研究超高速ＣＴ（ＵＦＣＴ）所见冠状动脉钙化与冠状动脉狭窄（＞５０％）之间的关系，并与冠状动脉造影对比评价其预测冠心病的敏感性及特异性。材料与方法：９０例临床怀疑或确诊冠心病患者，年龄在２７～７２岁之间（平均年龄５８．５岁），其中男８１例，女９例。所有患者均行ＵＦＣＴ检查及冠状动脉造影，两种检查时间间隔不逾１个月。ＵＦＣＴ扫描采用单层心电门控触发成像，扫描时间为１００毫秒，层厚为３ｍｍ。钙化灶定义为ＣＴ值＞１３０ＨＵ且面积＞１ｍｍ２者，冠状动脉造影采用常规方法。将ＵＦＣＴ所见钙化与冠状动脉造影对比，并计算其敏感性、特异性。结果：１６０支发现钙化的血管中，７４％有冠状动脉狭窄（＞５０％），１５４支造影证实冠状动脉狭窄（＞５０％）的血管中，７７％发现冠状动脉钙化。年轻组与老年组相比，冠状动脉钙化预测冠心病的敏感性较低而特异性较高。钙化在前降支发病率最高，其次为回旋支、右冠状动脉、左主干。结论：超高速ＣＴ检出冠状动脉钙化简便易行，有较高的敏感性、特异性，可广泛用于临床预测及早期诊断冠心病。     

64层螺旋CT冠状动脉成像质量影响因素的分析

目的:分析64层螺旋CT冠状动脉扫描中影响成像质量的各种因素。方法:对89例怀疑冠心病或冠心病复查患者进行64层螺旋CT冠状动脉检查,回顾性分析成像质量,探讨心率及心率波动对冠脉成像质量的影响,pitch值与心率的关系,替代(override)功能的应用价值,从而优化扫描参数。结果:①心率及心率波动与冠脉成像质量成负相关;②心率与扫描/重建方式及pitch值存在相互对应关系;③心率替代功能的合理使用可以提高CT冠状动脉的成像质量。结论:通过控制心率及心率波动,选择心率替代功能,采取适当的扇区扫描/重建模式可以提高图像质量和冠状动脉诊断的可靠性。     

左冠状动脉前降支重度狭窄CT血管成像的影像特征

目的 评价左冠状动脉前降支(LAD)重度狭窄CT血管成像(CTA)的影像特征.方法 回顾性分析同期行冠状动脉CT血管成像(CCTA)及选择性冠状动脉造影检查43例,LAD管腔狭窄＞70％,运用图像后处理软件在心脏短轴乳头肌层面,测量前壁、侧壁心肌CT值,结合收缩期及舒张期,测量心腔内径及节段心肌厚度,计算节段心肌收缩幅度及心肌增厚率,评价节段心肌早期灌注及心肌功能.以侧壁心肌作为对照,行单因素方差分析,P＜0.05认为有统计学差异.结果 病变位于LAD开口或近段17例(39.5％),位于近中段26例(60.5％),其中钙化斑块11例(25.6％),纤维斑块8例(18.6％),软斑块24例(55.8％).43例中,前壁心肌平均CT值(57.9±7.05) HU,41例心肌早期灌注减低(95.3％).侧壁心肌平均CT值(86.8±2.57)HU.心脏短轴乳头肌层面前壁心肌平均收缩幅度(32.2±7.75)％,侧壁心肌平均收缩幅度(46.3±4.02)％,前壁平均心肌增厚率(17.3±23.67)％,侧壁平均心肌增厚率(52.0±17.43)％.前壁心肌密度减低且伴有心肌功能减退33例.前壁与侧壁节段心肌CT值、心肌收缩幅度及节段心肌增厚率均存在显著性差异(P＜0.05).结论 CCTA能准确显示冠状动脉狭窄的部位、程度,可提供管壁斑块性质信息,冠状动脉管腔重度狭窄导致心肌早期灌注减低,且伴随相应节段心肌功能减低.