冠脉搭桥术后桥管的超声检查方法研究

目的探讨经胸超声检查冠脉搭桥术后桥管的显像方法及血流状态。方法采用经胸超声冠脉血流显像与高频血管显像相结合对左乳内动脉原位转流至左前降支、大隐静脉-右冠状动脉及大隐静脉-左回旋支桥管进行检查。结果左乳内动脉桥管、大隐静脉-右冠状动脉及大隐静脉-左回旋支桥管显示率分别为100%、93.75%和20%。左乳内动脉及大隐静脉桥管的血流均为舒张期为主的双期血流;左乳内动脉桥管的舒张期血流速度及流速时间积分大于大隐静脉桥管（P〈0.05）。结论经胸超声是术后桥管检查的较好方法,可用于无创的评估术后桥管血流状态。     

CT血管造影分析体外循环与非体外循环冠状动脉旁路移植后的桥血管通畅率

背景:近年来,非体外循环冠状动脉旁路移植后桥血管通畅率是否与传统的体外循环冠状动脉旁路移植相同存在争议.目的:探讨体外循环与非体外循环冠状动脉旁路移植后桥血管时间通畅率的差异性.方法:选取同一操作者行体外循环冠状动脉旁路移植患者100例,按其临床特征及桥血管病变危险因素匹配抽取非体外循环冠状动脉旁路移植患者137例.采用64排多螺旋CT血管造影分析冠脉搭桥后1个月,1年,2年,3年,4年的桥血管通畅情况.结果与结论:共对641条桥血管进行评价,两组中左侧乳内动脉桥血管时间通畅率均高于大隐静脉桥,两组左侧乳内动脉桥和人隐静脉桥血管时间通畅率比较差异均无显著性意义.说明非体外循环与体外循环冠状动脉旁路移植后患者桥血管时间通畅率相似,对于某些适当的患者来说,非体外循环冠状动脉旁路移植不失为一个良好的选择.     

CT血管造影分析体外循环与非体外循环冠状动脉旁路移植后的桥血管通畅率

背景：近年来,非体外循环冠状动脉旁路移植后桥血管通畅率是否与传统的体外循环冠状动脉旁路移植相同存在争议。目的：探讨体外循环与非体外循环冠状动脉旁路移植后桥血管时间通畅率的差异性。方法：选取同一操作者行体外循环冠状动脉旁路移植患者100例,按其临床特征及桥血管病变危险因素匹配抽取非体外循环冠状动脉旁路移植患者137例。采用64排多螺旋CT血管造影分析冠脉搭桥后1个月,1年,2年,3年,4年的桥血管通畅情况。结果与结论：共对641条桥血管进行评价,两组中左侧乳内动脉桥血管时间通畅率均高于大隐静脉桥,两组左侧乳内动脉桥和大隐静脉桥血管时间通畅率比较差异均无显著性意义。说明非体外循环与体外循环冠状动脉旁路移植后患者桥血管时间通畅率相似,对于某些适当的患者来说,非体外循环冠状动脉旁路移植不失为一个良好的选择。     

64排螺旋CT在评价冠状动脉桥血管中的价值

目的：探讨64排螺旋CT对冠状动脉桥血管病变评估的临床应用价值。方法：对21例冠状动脉搭桥术后患者，共77条桥血管（其中内乳动脉桥20条，桡动脉桥1条，大隐静脉桥56条）行64排CT造影（CTA）。扫描时患者平均心率（60±5）次/min。扫描范围从内乳动脉起始部到膈下2cm。冠状动脉桥血管的通畅和狭窄程度由两位有经验的医师来评估。其中9例桥血管或吻合口远端冠状动脉狭窄（≥50%）或闭塞的患者同时接受了传统冠脉造影检查。结果：21例患者CTA均获得了成功。冠状动脉主干及主要分支，均可见不同程度的狭窄或闭塞。显示冠状动脉桥血管通畅62条。闭塞10条（其中内乳动脉桥2条，静脉桥8条），显示桥血管近端吻合处狭窄（≥50%）3条，远端吻合处狭窄（≥50%）2条。吻合口远侧冠状动脉再狭窄或闭塞6例。9例CAG结果与CTA完全吻合。CTA显示冠状动脉桥血管狭窄（≥50%）或闭塞的准确性达100%。结论：CTA可准确评价冠状动脉桥血管以及吻合口再狭窄的程度。CTA可直观显示桥血管近端吻合口的位置，可指导冠状动脉搭桥术后CAG入路。是评估冠状动脉桥血管病变的首选方法。     

多层螺旋CT在冠状动脉桥血管评价中的应用

目的：评价多层螺旋CT在冠状动脉搭桥术后随访的临床应用价值.方法：选择2001-12/2005-04在东南大学医学院附属扬州医院行桥血管多层螺旋CT检查的冠状动脉搭桥术后患者12例,其中1例相隔1年后复查,共13次扫描检查资料.所有患者应用美国通用电气公司的十六排八层螺旋CT机,采用snapshot冠状动脉成像方法进行检测,并进行CT图像重建后处理,重建出各主要血管及桥血管.分析桥血管和冠状动脉的通畅性,评价狭窄及狭窄程度.结果：13例次患者的22支桥血管多层螺旋CT均能很好显示,其中17支桥血管开通,5支桥血管未开通（完全闭塞）或有不同程度狭窄.13例次患者原供血血管均可见不同程度管壁钙化、管腔狭窄或闭塞.结论：多层螺旋CT可以全面地显示心脏的结构与功能、心肌的血流灌注和存活状态,直接无创显示冠状动脉,对于冠状动脉桥血管开通和狭窄的评价具有很好的价值.     

320排容积CT在冠状动脉搭桥术后桥血管成像中的应用

目的：评价320排容积CT对冠状动脉搭桥术后桥血管成像的应用价值。方法：55例搭桥术后患者（男36例）,共计126条桥血管,其中52条动脉桥,61条静脉桥,13条序贯桥血管。所有患者在术后3~9个月进行320排容积CT桥血管成像检查,对所有病例图像进行后处理重建,包括多平面重组（MPR）、曲面重组（CPR）以及容积再现（VR）等。由2位有经验的放射科医生对重建图像进行观察,对桥血管成像质量进行评估（优、良、差）,并对桥血管的通畅性（通畅、轻度狭窄、中度狭窄、重度狭窄）进行初步评价。结果：55例患者均顺利完成冠状动脉桥血管320排容积CT成像检查,在待评价的126条桥血管中,116条桥血管显影,其中图像质量优97条（83.6％）、良19条（16.4％）,差0条（0％）,10条桥血管未见显影考虑闭塞。此外,发现8条动脉桥血管管壁存在钙化,5条动脉桥血管、5条静脉桥以及2条序贯桥血管可见近端或远端吻合口不同程度狭窄。结论：320排容积CT能够清晰显示冠状动脉桥血管,并且能够对桥血管及吻合口狭窄情况进行评估,是一种良好的无创性冠状动脉桥血管成像方法。     

多层螺旋CT在冠状动脉桥血管评价中的应用

目的:评价多层螺旋CT在冠状动脉搭桥术后随访的临床应用价值。方法:选择2001-12/2005-04在东南大学医学院附属扬州医院行桥血管多层螺旋CT检查的冠状动脉搭桥术后患者12例,其中1例相隔1年后复查,共13次扫描检查资料。所有患者应用美国通用电气公司的十六排八层螺旋CT机,采用snapshot冠状动脉成像方法进行检测,并进行CT图像重建后处理,重建出各主要血管及桥血管。分析桥血管和冠状动脉的通畅性,评价狭窄及狭窄程度。结果:13例次患者的22支桥血管多层螺旋CT均能很好显示,其中17支桥血管开通,5支桥血管未开通(完全闭塞)或有不同程度狭窄。13例次患者原供血血管均可见不同程度管壁钙化、管腔狭窄或闭塞。结论:多层螺旋CT可以全面地显示心脏的结构与功能、心肌的血流灌注和存活状态,直接无创显示冠状动脉,对于冠状动脉桥血管开通和狭窄的评价具有很好的价值。     

多层螺旋CT在冠状动脉搭桥术后的临床应用

目的评价多层螺旋CT(MSCT)在冠状动脉搭桥术后的应用价值。方法对40例冠状动脉搭桥术后患者,共有搭桥血管93条(乳内动脉30条,大隐静脉63条)。对40例患者分别行螺旋CT增强扫描和选择性冠状动脉造影(SCA)检查。所有MSCT检查采用回顾性心电门控技术、分段数据采集方式和选择75%的时间相位窗,对扫描数据进行后处理,由两位富有经验的医师评估并与SCA结果对照。结果所有近端桥血管及71.4%的远端搭桥血管通过MSCTA可显示,12条桥血管闭塞,66条通畅,13条有不同程度狭窄,1条远端桥血管狭窄并得到SCA证实,有4条假阳性,1条假阴性导致敏感性为94.5%,特异性为95.7%,阳性预测值80.4%,阴性预测值96.3%。结论多层螺旋CT可作为一种可靠的检查手段用于冠状动脉搭桥术后的评估。     

128层螺旋CT对冠状动脉搭桥术后桥血管病变的诊断研究

目的 探讨应用128层螺旋CT对冠状动脉旁路移植手术(CABG)术后桥血管病变的诊断价值.方法 对46例CABG术后(术后12～76个月)的患者行128层螺旋CT造影(MSCTA)检查,共检查133条桥血管,其中乳内动脉44条,大隐静脉89条.MSCTA检查后3～10d再行冠状动脉造影(CAG)检查,结果与MSCTA检查结果进行比较.结果 在133条桥血管中,MSCTA显示桥血管闭塞17条,桥血管狭窄(狭窄＞50％)20条.CAG结果显示桥血管闭塞17条,与MSCTA显示结果一致;桥血管狭窄(＞50％)有21条;与MSCTA检查结果比较,MSCTA检查结果假阳性1例,假阴性2例.计算MSCTA检查的敏感性为94.7％,特异性98.9％,阳性预测值97.3％,阴性预测值97.9％.结论 128层MSCTA检查可以比较准确地判断CABG术后桥血管的病变情况,是评价CABG术后桥血管病变的一种较好的无创伤检查方法.     

多层螺旋CT对冠状动脉桥血管的评价

目的评价16层螺旋CT对冠状动脉桥血管的显示能力。方法回顾性分析17例冠状动脉搭桥术(CABG)后患者的CT和选择性桥血管造影的资料,男15例,女2例,年龄51～78岁,平均(67±7)岁,术后6～85个月,平均(32±19)个月。共40支桥血管,原位乳内动脉13支,游离桡动脉11支,游离大隐静脉16支。由两位有丰富心血管影像诊断学经验的医生采用双盲法阅片,并取得一致结果。评价指标包括CT成像中桥血管的可评价性、有无闭塞或狭窄(管径缩小50%～99%)。结果所有40支桥血管均可评价,CT准确诊断5支桥血管闭塞和1支狭窄外,各有1例假阳性,其诊断桥血管闭塞与狭窄的敏感性、特异性达100%和97%,准确率分别为97.5%和97.1%。发生闭塞的血管与桥血管的类型和分布无关。结论16层螺旋CT是一种值得信赖的无创性随访研究桥血管通畅性的影像学方法。     

Initial experience with sequential internal mammary artery bypass grafts to the left anterior descending and left anterior descending diagonal coronary arteries

Early patency and late patency have consistently been better with single internal mammary artery grafts than with saphenous vein conduits. To determine the efficacy of these two types of grafts in sequential anastomoses, we performed sequential anastomoses of the left internal mammary artery to the left anterior descending and diagonal coronary arteries in 40 patients and compared the results with those in 58 patients who received sequential saphenous vein grafts. Treatment with dipyridamole (starting 48 hours before operation) and aspirin (added 7 hours after operation) was given to the 40 patients with internal mammary artery grafts and to 32 of the 58 patients in the saphenous vein group. After the bypass procedure, mean blood flows were as follows: 68 ml/min in patients with internal mammary artery grafts, 73 ml/min in patients who received saphenous vein grafts and a placebo, and 99 ml/min in those who received saphenous vein grafts, aspirin, and dipyridamole. Early patency of sequential internal mammary artery grafts to the diagonal and left anterior descending coronary arteries was comparable to that of sequential saphenous vein grafts. Because a substantial late reduction in patency has been noted in sequential saphenous vein grafts, sequential internal mammary artery grafts may be the preferred conduit for coronary artery revascularization.     

Assessment of coronary artery bypass graft patency by multidetector computed tomography and electron-beam tomography

This case report describes the use of retrospectively ECG-gated 16-slice multidetector computed tomography (MDCT) and electron-beam tomography (EBT) for assessing bypass graft patency in two patients with recurrent angina after coronary artery bypass graft surgery. The results of each tomographic modality were compared to the findings of traditional coronary angiography. In the first patient MDCT showed occlusion of the left internal mammary artery (LIMA) and saphenous vein graft after the second anastomosis. Coronary angiography confirmed these findings. In the second patient EBT showed patency of the LIMA and saphenous vein graft. After the first anastomosis of the saphenous vein graft, the connected vessel filled poorly. Coronary angiography confirmed both grafts to be patent, and detected an occlusion distal to the first anastomosis. These findings support the evidence that both MDCT and EBT are suitable techniques for establishing bypass graft patency by non-invasive means.     

升主动脉No—touch技术在冠心病手术中的应用

目的探讨和评价升主动脉不接触技术（No—touch）在冠状动脉旁路移植手术中的应用。方法回顾5例合并升主动脉粥样硬化冠心病患者的临床资料,男3例,女2例,年龄68--76岁,平均70．2岁。5例均采用常规胸骨正中切口行非体外循环下冠脉搭桥（OPCABG）。2例行双侧乳内动脉原位移植,3例以左乳内动脉为唯一的供血来源,大隐静脉近端与左乳内动脉端侧吻合。所有患者未在升主动脉上进行任何操作。结果5例患者共移植血管13支,全组手术均顺利完成,痊愈出院,无院内死亡。手术后所有忠者心绞痛均消失,心功能改善I～II级。无围术期心肌梗死和神经系统并发症发生。结论对合并升主动脉粥样硬化的冠心病患者,采用OPCABG结合升主动脉不接触（No—touch）技术,可使病变冠脉完全再血管化,降低术后脑卒中的发生率,临床效果满意。     

THE LIMA SUCCESS STORY — WHITHER OTHER ARTERIAL GRAFTS — ARE VEIN GRAFTS OBSOLETE ?

SUMMARY The long-term benefit of myocardial revascularisation depends largely upon the continued patency of bypass grafts, but the long-term patency of vein grafts is poor. To improve the results of myocardial revascularisation, either measures to increase the patency of saphenous vein grafts or alternative conduits are required. Use of the left internal mammary artery as a graft is known to increase survival, and this has prompted wider use of other arterial grafts in the expectation that they will further enhance the long-term results of coronary artery bypass. This policy is based upon sound theory, but convincing evidence that it improves survival is lacking. Meanwhile, advances in the understanding of the pathology of vein graft occlusion have given rise to new methods of increasing vein graft patency. While these techniques are, as yet, only experimental, if translated into clinical practice, the places of arterial and venous grafts may require further assessment.     

Multicenter radial artery patency study (RAPS). Study design

The use of an internal thoracic artery rather than a saphenous vein graft for left anterior descending coronary artery bypass is associated with improved long-term outcome. Hence, expanded use of arterial conduits for other coronary targets has been advocated. The radial artery possesses a number of anatomic features that are technically advantageous compared with other arterial conduits. This study will determine the relative patency of the radial artery compared to the saphenous vein for right and circumflex coronary bypass. Patients with graftable multivessel coronary disease and an estimated left ventricular ejection fraction >/= 35% undergoing nonemergent primary isolated coronary bypass surgery are eligible. The right and circumflex vessels must have high-grade lesions (>/= 70% diameter stenosis), with target segments of reasonable quality >/= 1.5 mm in diameter. Patients serve as their own controls. The radial artery is randomly allocated to bypass the right or circumflex territory and a saphenous vein is used for the nonradial site. An internal thoracic artery is used for the left anterior descending coronary artery in all cases. Randomization is stratified by center. The primary study endpoint is graft patency as determined by angiography, 8-12 months postoperatively. The relative patency of the radial artery compared with the saphenous vein will be determined using McNemar's test. A sample size of 464 patients will provide 80% power for a two-tailed test (alpha = 0.05) for a 40% relative reduction in the rate of distal anastomotic occlusion from 12% in the saphenous vein to 7.2% in the radial arteries assuming a 20% within-patient correlation. A single interim analysis will be performed following completion of 232 angiograms. To allow for lack of follow-up angiography in up to 20% of enrolled patients, we plan to randomize a total of 560 patients. It is also our intention to assess the long-term patency (5-10 years) of radial artery relative to saphenous vein grafts in follow-up studies. Three hundred patients were recruited from 12 Canadian, university-affiliated sites from November 1996 until February 1999, of which 128 patients have undergone follow-up angiography. Approximately 80% of those who have been followed for more than 1 year have undergone follow-up angiography. This trial will determine the 8-12 month patency of the radial artery relative to the saphenous vein for non-left anterior descending coronary bypass using a novel study design which helps control for potential bias from individual patient and vessel factors. Positive results would support the use of the radial artery in particular, and multiple arterial grafts in general.     

Technical considerations in aortocoronary bypass grafting

Since the inception of aortocoronary bypass surgery, many technical advances have been rapidly achieved. Early experience was limited to reversed saphenous vein grafting of single vessel coronary artery disease. Multiple grafts to several vessels soon became commonplace and sequential grafting techniques were developed. Expanded use of the internal mammary artery resulted after analysis of superior patency rates achieved with this conduit. Use of alternative conduits such as upper extremity veins, allogenic veins, synthetic graft material (polytetrafluorethylene), radial artery, splenic artery, and gastroepiploic artery have been explored. Apart from the gastroepiploic vessel, none of these alternative conduits have been suitable. A grat deal of effort has been directed at the mechanisms of saphenous vein occlusion including technical considerations, early thrombosis, intimal hyperplasia and graft atherosclerosis. Platelet inhibition and lipid reduction have shown promise in improving patency rates. Further work in these areas should lead to even better results.     

Non-selective intra-arterial digital subtraction angiography for the assessment of coronary artery bypass grafts

Non-selective intra-arterial digital subtraction angiography (DSA) was performed immediately before selective coronary and bypass angiography in 33 consecutive symptomatic patients 48± 30 months after coronary surgery, for the assessment of 75 coronary bypass grafts. Forty ml of non-ionic, low-iodine content contrast medium (iohexol) were injected into the ascending aorta at 10–20 ml/sec through a 7 or 8 F femoral pigtail catheter. Electrocardiogram-triggered images were acquired on a Siemens Digitron II apparatus in multiple projections in 24 patients and in a single projection in 9 patients. The results of this technique were compared by two independent angiographers with those of selective graft angiography in the same patients. Patency was shown by DSA in 45 of 54 grafts confirmed to be open by selective angiography (sensitivity 83%). Of 21 occluded grafts, stumps were clearly visible at selective angiography in 18 and at DSA in 9 (sensitivity for graft stumns = 50%, p<0.01) Of 54 patent grafts with selective angiogranhy. the distal anastomosis could be visualized by DSA in 28 (52%), but the resolution was comparable to selective angiography in 20 grafts (37%) only. A non-significant difference in the sensitivity of DSA was observed between patent saphenous grafts to the left anterior descending coronary artery versus all other coronary arteries (95 vs 85%, respectively), while only 1 of 5 patent left internal mammary artery grafts to the left anterior descending coronary artery was visualized. In 16 of 50 grafts (32%) visualized in a second projection substantial additional diagnostic information was obtained. In conclusion, non-selective intra-arterial electrocardiogram-triggered DSA can visualize patent saphenous grafts with a high sensitivity and may be a useful screening tool for bypass grafts patency; false negatives, however, and poor visualization of distal anastomoses limit its routine clinical use.