冠状动脉肌桥前动脉粥样硬化性狭窄的易患因素研究

目的探讨冠状动脉肌桥前动脉粥样硬化性狭窄的易患因素。方法接受冠状动脉造影的88例心肌桥患者,其中合并肌桥前动脉粥样硬化性狭窄者67例（A组）,未合并肌桥前动脉粥样硬化性狭窄者21例（B组）,观察两组患者的年龄、性别、心肌桥长度、收缩压、舒张压、脉压、心肌桥压迫程度（Nobel分级）、空腹血糖、血脂等因素的差异。结果两组患者Nobel分级、收缩压、脉压比较差异均有统计学意义（P〈0．05）。而年龄、性别、心肌桥长度、舒张压、空腹血糖、总胆固醇、低密度脂蛋白胆固醇水平比较差异无统计学意义。进一步回归分析发现,Nobel分级和脉压与是否合并肌桥前动脉粥样硬化性狭窄有相关性（相关系数分别为3．0569和0．9740,P值均〈0．05）。结论高血压患者易患心肌桥,心肌桥有促发或加速肌桥前动脉发生粥样硬化的倾向,心肌桥压迫程度、脉压与是否合并肌桥前动脉粥样硬化性狭窄显著相关,而年龄、性别、收缩压、舒张压、空腹血糖、血脂、心肌桥长度与是否合并肌桥前动脉粥样硬化性狭窄无相关性。     

Coronary endarterectomy for diffuse extensive coronary artery disease

Introduction Atherosclerotic coronary artery disease is in an increasing trend in India. With the advancement of non-surgical methods of revascularisation, the patients coming for surgery are of less attractive anatomy. The role of coronary endarterectomy along with coronary artery bypass grafting for a selected group of these patients is quite promising. Materials and Methods From March 2000 to March 2005, out of 362 CABGs performed, 42 patients had undergone coronary endarterectomy. The age range being from 35 to 76 years, M: F is 38∶4 Hypertension was present in 26 (61%), diabetes mellitus in 20 (47.6%), smoking in 26 (61%) and dyslipidemia in 12 (28.5%) cases. Old myocardial infarction was present in 52.3% cases, unstable angina in 16.6%, stable angina in 23.8% and cardiogenic shock in 7.1% cases. All cases had undergone coronary artery bypass grafting with endarterectomy. Out of 18 LAD endarterectomies 17 cases LIMA was used as onlay patch. Result The average number of grafts anastomosed was 3.7. Single-vessel endarterectomy was done in 37, double vessel in 4 and four vessel in one case. LAD endarterectomy was done in 18, RCA in 12, diagonal in 10, intermediate in 1 and marginals in 8 cases. Postoperatively 3 patients had arrhythmia, two perioperative MI, one recurrent angina and one congestive cardiac failure (CCF). There was 2 (4.76%) mortality. Conclusion Hypertension and smoking are major risk factors. LAD is the most common artery requiring endarterectomy. Usage of LIMA following endarterectomy of LAD is quite satisfactory and short term results are encouraging.     

多层螺旋CT冠脉成像的临床应用

目的旨在评价多层螺旋CT(MSCT)在冠状动脉疾病诊断中的作用。方法57例患者,按心率≤60次/min、60～70次/min、>71次/min分成3组,行冠脉MSCT造影(MSCTA),将数据在回顾性心电门控下行最大密度投影(MIP)、容积重建(VR)和多平面重建(MPR),观察其对冠状动脉的显示,其中11例与选择性冠状动脉造影(SCA)对照。结果心率≤70次/min患者CT图像质量明显优于心率>70次/min组(P<0.001)。11例与相应的SCA比较,MSCTA诊断50%以上狭窄的敏感度、特异度、阴性预测值和准确度分别为88.9%、71.4%、86.7%和83.3%。结论MSCT能显示冠状动脉钙化和狭窄、进行冠脉支架术后评价。     

冠状动脉旁路移植术1018例临床分析

目的总结、探讨冠状动脉搭桥术的外科技术及临床治疗效果。方法回顾分析1997—2004年同一术者完成的冠状动脉搭桥术1018例患者的临床资料,其中非体外循环冠状动脉旁路移植术(OPCAB)510例,体外循环下冠状动脉旁路移植术(CCABG)508例。≥60岁的患者582例(57.2%)。不稳定性心绞痛患者852例;术前同时合并其他疾病患者784例(77.0%),包括瓣膜病、高血压病、糖尿病、陈旧性心肌梗死、室壁瘤、室间隔穿孔、脑梗死、阻塞性肺疾病(COPD)、慢性肾功能不全、恶性肿瘤术后等。左主干病变156例;三支病变671例,三支病变以下347例。结果死亡4例(0.39%),总体并发症(胸骨哆开、脑梗死、纵隔炎)发生率1.6%(16/1018)。OPCAB者平均搭桥(2.5±0.4)支,CCABG者平均搭桥(3.3±0.6)支。左乳内动脉使用率93.8%(955/1018),术后早期使用主动脉内气囊反搏29例。全组随访2个月～7年,随访1002例(98.4%)。结论科学的外科策略,精湛的手术技术及麻醉、体外循环技术的改进,可使CABG术的死亡率和并发症明显下降,冠状动脉旁路移植术安全、可靠,效果满意。     

血管内超声显像在冠心病支架植入术中的应用

目的探讨血管内超声在冠心病支架植入中的作用。方法50例患者的52处病变在支架植入前后分别用血管内超声进行定量和定性分析,并根据血管内超声标准决定支架的直径以及植入的终点,分析CAG和IVUS对支架植入终点判断的差异和最终获得的管腔面积大小的差别以及支架后管腔面积增大的机制。结果IVUS比CAG判断的平均支架直径大[(3.48±0.29)mmvs(3.36±0.33)mm,P=0.011],支架囊的最终峰值压力明显增大[(17.7±2.9)atmvs(12.8±2.4)atm,P<0.001],QCA测得的支架面积狭窄百分比减小(13.2%±6.6%vs16.6%±9.1%,P=0.044);首次高压扩张后支架满意率CAG达96.2%,而IVUS只有37.7%。IVUS指导后最终的球囊压力更高[(16.13±1.87)atmvs(12.62±2.61)atm,P<0.001],获得的管腔直径更大[(3.64±0.53)mmvs(3.31±0.57)mm,P<0.001],管腔面积也更大[(9.90±2.05)mm2vs(8.84±1.67)mm2,P<0.001],面积狭窄百分比更小(49.15%±9.03%vs54.24%±10.05%,P<0.001];所有患者支架的近段和远段CAG均未发现明显的狭窄。而IVUS却发现支架近段血管有39例(75.0%),远段血管有23(44.2%)例存在动脉粥样硬化斑块;支架植入后非脂质斑块较脂质斑块获得的管腔面积更大[(4.50±1.67)mm2vs(3.68±0.97)mm2,P<0.001],其中脂质斑块血管面积增大较非脂质斑块小1.30mm2,斑块压缩程度却增加0.48mm2。结论IVUS较CAG能更好地判断病变的性质,指导支架更好地选择,可获得更大的管腔面积,更小的面积狭窄百分比。     

Long-term coronary artery outcome after arterial switch operation for transposition of the great arteries

Objective: To analyse the long-term patency of coronary arteries after neonatal arterial switch operation (ASO). Methods: A retrospective study of the operative reports, follow-up and postoperative catheterisation data of 119 patients, who underwent the great arteries (TGA) repair since 1991, has been carried out. Patient population: Among the 133 survivors of the 137 ASOs performed between 1991 and 2007, 119 patients have been studied by routine control cardiac catheterisation and form the study population. Median time between repair and the coronary angiography was 2.9 ± 1.9 years. A comparison between the eight patients (6.7% out of the entire study population), known to have postoperative coronary obstructions (group I) and the rest of the cohort with angiographic normal coronary vessels (group II) was performed by univariate analysis of variance and logistic regression models. One patient had surgical plasty of the left coronary main stem with subsequent percutaneous angioplasty, three patients had primary coronary stent implantation and four patients had no further intervention at all. In group I, all but one patient denied symptoms of chest pain and echocardiography failed to show any difference between the two groups in terms of left ventricular systolic function (ejection fraction group I 61 ± 2% vs 62 ± 6% of group II, p = 1.0). Results: The association of coronary obstruction with complex native coronary anatomy (Yacoub type B to E) was evident at both univariate (62% of group I vs 22% of group II, p = 0.04) and logistic regression (p = 0.007, odds ratio (OR) 8.1) models. The type of coronary reimplantation (i.e., coronary buttons on punch vs trap-door techniques) was similar between the two groups (punch reimplantation in 25% of patients of group I vs 31% of group II, p = 0.1) as was the relative position of the great vessels (aorta anterior in 100% of patients of group I vs 96% of group II; univariate, p = 0.1). Conclusions: The late outcome in terms of survival and functional status after ASO is excellent. Nevertheless, the risk of a clinically silent late coronary artery obstruction of the reimplanted coronary arteries warrants a prolonged follow-up protocol involving invasive angiographic assessment.     

冠心病患者动脉粥样硬化性肾动脉狭窄的临床筛选方法研究

目的建立从临床上筛选出动脉粥样硬化性肾动脉狭窄（ARAS）的简单易行的预测公式。方法分析892例冠状动脉造影并行非选择性肾动脉造影患者的临床资料，采用单因素相关分析得出与ARAS相关的风险因素，再通过多因素Logisitc回归分析得出各风险因素之间的比例关系，根据这种比例关系建立简单的评分系统，再将评分代人患者中，分析其敏感性及特异性。结果在冠状动脉粥样硬化人群中ARAS的患病率为12．7％，风险因素为年龄、体质量指数、血肌酐、高血压病史、糖尿病病史、缺血性脑血管病病史与顽固性高血压。根据以上风险因素建立相应的评分系统，患者的评分分值由5．5分至20．5分不等。随着分值的增加，ARAS的发病率明显升高。结论本研究所建立的简单临床预测公式可以有效的对冠状动脉粥样硬化患者进行初步的筛选，为是否采取敏感度高但较为昂贵的检查进行确诊提供参考。     

Real-time patency control with thermal coronary angiography in 1401 coronary artery bypass grafting patients

Objective: Intraoperative coronary angiography has always been favoured by cardiac surgeons. Thermal coronary angiography (TCA) is a useful method for intraoperative control of graft patency. It detects heat differences between tissues, provides easy-to-interpret angiographic images and even measures the flow of the grafts quantitatively. Methods: Between January 2000 and January 2002, TCA has been used in scheduled coronary bypass operations. Upon completion of each distal anastomosis, the perfusion of the distal arterial tree from the graft was evaluated with a thermal camera. Results: TCA was applied to 1401 patients, mean age 60.97±9.61 years, who underwent simple coronary artery bypass grafting (CABG) procedures. A total of 4105 thermal images were obtained including 2161 venous, 1355 single internal thoracic artery (ITA), 56 bilateral ITA and 477 radial artery grafts. Image quality was not sufficient in 34 grafts (1.57%) due to either deep intramyocardial vessels or excessive epicardial fat tissue. Technical failures in three ITA anastomoses were detected and revised before the cross-clamp was removed. Flow-restricting lesions distal to the anastomosis on the left anterior descending artery (LAD) in nine patients were managed with a secondary distal bypass graft (five patients) or plaque splitting and anastomotic revision (four patients). Endarterectomy was combined in seven patients since the graft flow and the distal visualization was not satisfactory, although the anastomoses were performed on a good lumen. Angiographically undetected diagonal arteries were revascularized in 11 patients with totally occluded LAD vessels. Conclusion: Thermal imaging provides decisive coronary angiographies, and detects the perfusion area and flow of the implanted graft. It allows real-time detection of technical failures, reveals unexpected occluding plaques or any kind of flow-restricting lesions, and gives the chance of refinement of the anastomosis during the arrest period. We believe that the thermal imaging technique is a safe, noninvasive and feasible method to document the quality of the myocardial revascularization intraoperatively.     

Influence of opioids on the vascular tone of isolated porcine coronary artery segments

BACKGROUND: It was the aim of this study to elucidate the influence of opioids on coronary vascular tone using the model of isolated porcine coronary artery segments. METHODs: We studied the effects of fentanyl (0.01, 0.1, 1.0 microg ml(-1)), alfentanil (0.1, 1.0, 10 microg ml(-1)), and sufentanil (0.01, 0.1, 1.0 microg ml(-1)) on the contractile response to three vasoconstrictors, acetylcholine, histamine and serotonin. RESULTS: Fentanyl (0.1, 1.0 microg x ml(-1)) dose-dependently attenuated the contractile response to acetylcholine, but not to histamine and serotonin. There were no differences in fentanyl's vasorelaxing potency between rings with intact and denuded endothelium. Alfentanil and sufentanil did not exert any significant influence on any of the vasoconstrictors tested. CONCLUSION: It is concluded that, in isolated porcine coronary artery rings, fentanyl at high concentrations has an attenuating effect on acetylcholine-induced contractions, which is independent of endothelial function, whereas alfentanil and sufentanil do not influence coronary vascular tone.     

Screening for coronary artery disease in early surgical treatment of acute aortic valve infective endocarditis

OBJECTIVESIn patients with unknown coronary status undergoing surgery for acute infective endocarditis (IE), the need to screen for coronary artery disease (CAD) and the risk of embolization during invasive coronary angiography (ICA) are debated. Coronary computed tomography angiography (CCTA) is a non-invasive alternative in these patients. We aimed to evaluate the safety and feasibility of ICA and CCTA to diagnose CAD, and the necessity to treat CAD to prevent CAD-related postoperative complications. Open in a separate windowMETHODSIn this single-centre retrospective cohort study, all patients with acute aortic IE between 2009 and 2019 undergoing surgery were selected. Outcomes were any clinically evident embolization after preoperative ICA, in-hospital mortality, perioperative myocardial infarction or unplanned revascularization and postoperative renal function.RESULTSOf the 159 included patients, CAD status was already known in 14. No preoperative diagnostics for CAD was done in 46/145, a CCTA was performed in 54/145 patients and an ICA in 52/145 patients. Significant CAD was found after CCTA in 22% and after ICA in 21% of patients. In 1 of the 52 (2%) patients undergoing preoperative ICA, a cerebral embolism occurred. The rate of perioperative myocardial infarction or unplanned revascularization in patients not screened for CAD was 2% (1 out of 46 patients).CONCLUSIONSAlthough the risk of embolism after preoperative ICA is low, it should be carefully weighed against the estimated risk of CAD-related perioperative complications. CCTA can serve as a gatekeeper for ICA in most patients with acute aortic IE.     

冠状动脉旁路移植术的中远期效果随访

目的 分析冠状动脉旁路移植术(CABG)的中、远期疗效.方法 CABG术后行多层螺旋CT(MDCT)复查42例,行冠状动脉造影(SCA)复查59例;平均随访(66.79±44.27)个月.其中动脉旁路血管115支,静脉旁路血管195支.分别计算旁路血管的通畅率,比较其间的差异.结果 行MDCT复查者随访(53.93±36.80)个月,LIMA、RA、SV和CV的通畅率分别为94.7%、92.0%、85.9%和60.0%;有心绞痛再发组为83.5%,无心绞痛再发组为95.2%,差异有统计学意义.SCA复查者随访(75.95±47.09)个月,LIMA、RA、SV和CV的通畅率分别为87.1%、81.0%、53.6%和57.1%;有心绞痛再发组为62.0%,无心绞痛再发组为100.0%,差异有统计学意义.结论 MDCT可以作为一种无创检查方法来评价CABG术后旁路血管的通畅情况;动脉旁路血管的中、远期通畅率较静脉高;旁路血管病变是导致术后再发心绞痛的重要原因;旁路血管病变程度与CABG术后的随访时间密切相关.     

70岁以上冠状动脉旁路移植术病人乳内动脉流量测量分析

目的 分析70岁以上冠状动脉旁路移植术病人乳内动脉旁路血管血流量的特点.方法 对2003年1月至2007年1月间78例70岁以上(含70岁)应用乳内动脉非体外循环冠状动脉旁路移植手术(OPCAB)的病人,使用瞬时超声血流测量技术对其乳内动脉平均血流量、搏动指数等指标进行测量并分析.结果 78例病人83根乳内动脉旁路血管平均流量(36.0±21.5)ml/min,平均搏动指数3.50±1.76,血流波形均以舒张期为主.男女性别比、平均流量和搏动指数差异无统计学意义[(39.0±23.1) ml/min对(28.0±14.7) ml/min;(3.30±1.50)对(4.10±2.22),P>0.05],但女病人平均流量较男病人偏低,搏动指数较男病人偏高.结论 70岁以上病人冠状动脉旁路移植术应用乳内动脉是安全、有效的;对老年病人乳内动脉流量的评价分析应当结合老年病人的病变特点.     

急性前壁心肌梗死患者心电图表现与冠脉造影对比研究

目的分析急性前壁心肌梗死的梗死相关血管特点和心电图分布特征，为临床判断冠状动脉病变部位提供线索。方法经冠状动脉造影证实为单支血管病变的142例初发急性前壁心肌梗死患者，根据心电图表现分为四组。比较各组间梗死相关动脉的病变特点。结果单纯前壁心肌梗死的犯罪血管病变82％（36／44）在前降支中段，前壁心肌梗死合并下壁导联ST段压低的犯罪血管病变80％（24／30）在前降支近段，前壁心肌梗死合并下壁导联ST段抬高者，犯罪病变54％（20／37）在右冠状动脉，46％（17／37）在左前降支，广泛前壁心肌梗死的犯罪病变主要在前降支近段85％（23/27），P〈0．001；前壁心肌梗死是否合并下壁导联ST段偏移，其血管病变程度与侧支循环建立相近，均好于广泛前壁心肌梗死患者。结论根据心肌梗死时心电图异常的分布特点，可以推测急性前壁心肌梗死病变的部位，良好的侧支循环有助于限制梗死面积。     

先天性冠状动脉瘘的临床分析

目的：探讨61例先天性冠状动脉瘘(CAF)的临床特点及治疗方法。方法：1984年至2002年，应用超声心动图、升主动脉及选择性冠状动脉造影检查确诊CAF 61例。其中男34例，女27例；年龄5个月至71岁。其中51例为单纯性CAF，10例伴其他先天性畸形。单支娈管起源于左冠状动脉26例，右冠状动脉29例。结果：8例未进行有创干预治疗。46例行外科手术治疗。治愈44例；死亡2例。均为合并其他先天性畸形者。7例行导管栓堵治疗，6例治愈。1例因导管到位困难停止手术。结论：超声心动图及选择性冠状动脉造影是冠状动脉瘘主要确诊手段。外科手术和经导管栓堵术闭合冠状动脉瘘均安全有效，应在临床症状出现前进行根治性治疗。     

16层CT与导管法造影在显示冠状动脉狭窄中的对照研究

目的探讨16层CT冠状动脉成像在显示冠状动脉狭窄中的应用价值和限度。方法回顾性分析52例临床诊断或可疑冠心病患者的16层CT冠状动脉成像检查结果,并将16层CT检查结果与导管法冠状动脉造影结果进行对照。结果在52例患者的冠状动脉直径≥2 mm的580节段中,CT图像能满足管腔评价为507节段(占87.41%)。在CT图像能满足管腔评价的冠状动脉节段中,16层CT显示中度或中度以上狭窄(≥50%)的敏感度、特异度和阳性、阴性预测值分别为87.88%、98.17%和76.32%、95.96%,若将CT图像不能满足管腔评价的中度或中度以上狭窄的5个节段包括在内,其敏感度为81.69%;16层CT显示高度狭窄(≥75%)的敏感度、特异度和阳性、阴性预测值分别为83.78%、99.35%和91.18%、98.7%,若将CT图像不能满足管腔评价的高度狭窄的2个节段包括在内,其敏感度为79.49%。结论16层CT在对冠状动脉中、高度狭窄的初步诊断及介入治疗的筛选方面,可部分取代导管法冠状动脉造影。     

老年患者冠状动脉造影术后不同股动脉止血方法的效果比较

目的：评价冠状动脉造影及经皮冠状介入治疗术后老年患者股动脉穿刺部位不同止血方法的效果及安全性.方法：268例行冠状动脉造影及经皮冠状动脉介入治疗的老年患者,平均年龄63.8岁,根据不同股动脉止血方法分为3组.A组82例采用徒手压迫法止血 B组87例采用M-GU动脉压迫器止血 C组99例采用Angio血管闭合器止血.比较3组患者术后制动时间、止血效果及术后并发症发生率.结果：A组止血成功率为98.8%（81/82例）,B组为97.7%（85/87例）,C组为96.0%（95/99例）,3组间差异无统计学意义（P＞0.05）.止血和制动时间比较,C组[（4.3±1.1）min和（4.9±0.9）h]少于B组[（6.2±1.2）min和（12.2±1.5）h],B组少于A组[（23.2±3.6）min和（25.7±2.3）h].并发症的发生情况：3组间局部渗血和假性动脉瘤的发生率差异无显著性 尿潴留和腰痛并发症的发生率差异存在显著性,C组（2.0%和7.1%）低于A组（14.6%和42.7%）和B组（6.9%和20.7%）.结论：3种止血方法的止血效果无差异,但是应用血管闭合器止血可以有效缩短老年患者止血时间及下肢制动时间,减少并发症发生,患者易于接受.     

64层CT诊断冠状动脉狭窄的准确性:与常规血管造影比较

目的评价64层螺旋CT冠状动脉造影对冠状动脉明显狭窄诊断准确性和可行性。方法218例冠心病疑似患者在一周内进行了64层CT冠状动脉造影及常规血管造影,对冠状动脉的主干及主要分支进行诊断,以冠状动脉造影结果为金标准评价64层CT诊断冠状动脉狭窄的准确性。结果多层螺旋CT所显示的2592支冠状动脉中冠状动脉狭窄173处,正确诊断166处,漏诊7处,误诊28处,敏感性95.9%,特异性98.6%,阳性预测值90.2%,阴性预测值99.7%,准确率98.4%。结论64层螺旋CT对冠状动脉狭窄诊断有较高的准确性,可作为高危人群普查筛选的首选方法之一。     

冠状动脉内膜剥脱联合旁路移植治疗弥漫性冠状动脉狭窄病变的近中期效果

目的探讨冠状动脉内膜剥脱术(CE)联合冠状动脉旁路移植术(CABG)治疗弥漫性冠状动脉狭窄病变的近中期效果。方法回顾性分析2010年1月至2019年1月在南京市第一医院心胸血管外科接受CE+CABG的248例弥漫性冠状动脉狭窄病变患者的临床资料。男性201例,女性47例;年龄(65.6±8.5)岁(范围:43~79岁)。体外循环手术156例,非体外循环手术92例。共对269根病变血管完成CE,包括前降支108根,右冠状动脉140根,钝缘支21根。共完成旁路移植872支,包括左胸廓内动脉248支,桡动脉48支,大隐静脉576支,每例患者移植(3.5±0.8)支(范围:2~6支)。CE后平均血流量为(26±8)ml/min(范围:13~59 ml/min),血流指数为3.1±0.8(范围:2.0~6.7)。采用t检验或χ²检验比较体外循环和非体外循环患者的手术结果及术后通畅率。结果全组围手术期病死率为1.2%(3/248),2例死于肾功能衰竭,1例死于术后顽固性低心排血量。9例发生围手术期心肌梗死。随访(41.8±21.4)个月(范围:1~68个月)。旁路血管术后1年通畅率为78.4%(182/232),3年通畅率为69.8%(162/232)。左冠状动脉系统通畅率明显高于右冠状动脉系统(1年:87.4%比73.1%,χ²=6.533,P=0.011;3年:78.2%比64.8%,χ²=4.588,P=0.032)。体外循环组和非体外循环组旁路血管通畅率无差异(1年:80.0%比76.9%,χ²=0.277,P=0.599;3年:71.5%比67.9%,χ²=0.300,P=0.584)。结论CE+CABG治疗弥漫性冠状动脉狭窄病变可以获得较满意的完全再血管化,有较好的早、中期效果和旁路血管通畅率。体外循环和非体外循环手术具有相似的早中期结果。     

MSCTA结合心肌首过灌注成像诊断冠状动脉狭窄

目的探讨MSCT血管造影(MSCTA)结合心肌首过灌注成像诊断冠状动脉狭窄的价值。方法对80例可疑冠心病患者行64排MSCTA检查,按MSCTA成像质量分为A组(n=41,血管显示清晰)和B组(n=39,血管显示不清);以CAG结果为金标准,计算并比较MSCTA和MSCTA结合心肌首过灌注成像诊断冠状动脉狭窄的准确率。结果A组中MSCTA诊断冠状动脉狭窄准确率[85.98%(141/164)]高于MSCTA结合首过灌注成像[80.49%(132/164)],B组中MSCTA诊断冠状动脉狭窄准确率[66.03%(103/156)]低于MSCTA结合首过灌注成像[79.49%(124/156)],差异均有统计学意义(P均0.05)。结论 MSCTA诊断冠状动脉狭窄时,对于血管显示不清者,结合心肌首过灌注成像能明显提高诊断准确率。