非体外循环心脏跳动下冠状动脉旁路移植术桥血流的研究

目的　术中测量非体外循环心脏跳动下冠状动脉旁路移植术 (OPCAB)桥血管的血流量和搏动指数 (PI)及血流波形 ,以探讨血管桥通畅率及其与波形的关系。方法　 2 34例病人接受OPCAB手术 ,采用左乳内动脉 (LIMA)全部与左前降支 (LAD)吻合 ,大隐静脉 (SV)吻合口在 2个以上采用序贯式吻合。术中用超声血流检测仪 (medi stimbutterflyflowmeter)测量旁路血管桥的血流量、PI值及其波形 ,根据结果判断桥路通畅情况 ,并且对比LIMA和SV旁路血管桥的血流量和LIMA中LAD近段狭窄大于 90 %与小于 90 %者的血流量。结果　LIMA使用率 10 0 % ,LIMA和SV桥通畅率 10 0 % ,LIMA平均血流量(19 99± 1 93)ml/min ,SV血流量 (38 17± 2 85 )ml/min ,两者差异显著 (P <0 0 1)。LIMA组中LAD近段狭窄大于 90 %者血流量 (32 0 0± 3.4 0 )ml/min ,小于 90 %者血流量 (15 2 9± 1 6 6 )ml/min ,两者差异显著(P <0 0 1)。PI平均值LIMA为 3 2 9± 0 2 2 ,SV为 3 4 1± 0 37。术后病人无并发症 ,心绞痛消失 ,全部治愈出院 ,平均住院 (7 0± 1.5 )d。随访无死亡。结论　OPCAB术吻合口的通畅率令人满意 ,静脉桥血流量高于LIMA ;LAD近段狭窄大于 90 %时LIMA血流量较高。反映桥通畅的最可靠指标是桥血流的搏动指数 ,而舒张期血流的波     

瞬时流量测定技术在冠状动脉旁路移植术中的应用及其相关因素分析

目的 评估瞬时流量测定（transit time flow meter，TTFM）技术在冠状动脉旁路移植术（CABG）中探查移植血管血流通畅状态的应用价值，并分析其测定结果的相关因素。方法 对我科2002年3月至2004年1月连续行CABG301例患者的791支血管移植物进行TTFM测定，按照入选标准从中筛选出左乳内动脉（LIMA）旁路移植到左前降支（LAD）的165例患者的TTFM结果，进行血流量和搏动指数（pulsatility index，PI）的多因素分析。结果 TTFM技术提示，791支移植物中有严重质量问题的移植血管5支，均手术证实并加以改正。可能影响移植物血流量的主要因素为LAD远端直径、LIMA直径、心肌梗死位置、LAD近端狭窄程度、反流量百分比（percentage of insufficiency）、左心室舒张期末内径、手术方式（体外循环和非体外循环）；影响P1值的主要因素为LAD远端直径、反流量百分比和手术方式。结论 TTFM在判断CABG移植物状态时具有一定的诊断价值。多种因素均可影响移植物的血流量和P1值，应考虑主要影响因素以及临床表现来提高TTFM诊断技术错误的敏感性。     

竞争血流与冠脉移植血管的相互作用

目的探讨竞争血流对冠脉移植血管血流量的影响。方法健康成年犬12只(体重27.62±1.63 kg),在非体外循环心脏不停跳下行冠状动脉旁路移植术(CABG),术中应用即时血流测量仪对不同的狭窄级别进行分组,分为无狭窄组,33%狭窄组、50%狭窄组和75%狭窄组,在相对恒定的血压和心率范围内,阻断和不阻断竞争血流时分别测量心率(HR)、平均动脉压(M AP)移植血管的血流量和搏动指数(P I)。结果在相对恒定的血压和心率范围内阻断竞争血流后各组的移植血管血流量均较不阻断竞争血流时明显升高。阻断和不阻断竞争血流时无狭窄组、33%狭窄组的P I均低于正常;50%狭窄组阻断竞争血流较不阻断竞争血流时P I下降(从8.36±3.52下降到3.02±0.94);75%狭窄组P I>5。结论竞争血流可抑制冠脉移植血管血流量,CABG中吻合点的选择将可能影响移植血管的通畅性。     

再次冠状动脉旁路移植术的临床应用

目的总结再次冠状动脉旁路移植术(CABG)治疗冠心病的临床经验和手术效果。方法2001年6月～2006年12月,对18例冠心病患者行再次CABG。术前心绞痛(CCS分级)级7例,级11例;冠状动脉造影显示:16例均有原移植静脉狭窄/闭塞,2例左乳内动脉(LIMA)-左前降支(LAD)桥狭窄/闭塞,6例自体冠状动脉出现新的病变。全组均经原胸骨正中切口径路手术,常规体外循环(CPB)下CABG15例,非体外循环冠状动脉旁路移植术(OPCAB)3例;同期行室壁瘤切除、左心室成形1例,二尖瓣成形术3例,主动脉瓣和二尖瓣双瓣膜置换联合右颈动脉内膜剥脱术1例。应用LIMA12例次、双侧IMA4例次、桡动脉3例次,其余为大隐静脉或小隐静脉。结果15例常规CABG患者主动脉阻断时间45～112min(57±26min),CPB时间66～140min(78±24min)。再次CABG每例移植血管1～5支,平均每例远端吻合口3.11个。手术结束用血流仪测定移植血管血流量均满意(血流量27.0±12.5ml/min),搏动指数均<4.2。手术后因低心排血量需主动脉内球囊反搏辅助1例,术后6d发生肾功能衰竭死亡。其余17例患者术后呼吸机辅助呼吸时间5～15h,心绞痛均消失,围手术期无心肌梗死发生,胸腔引流量为290～1040ml,顺利恢复,均出院。术后随访17例,随访时间6.0个月～4.5年,均无心绞痛发作,4例复查冠状动脉造影,显示移植血管均通畅。结论再次CABG难度大于首次CABG,但只要手术中能正确找到靶血管,移植血管的血流可靠、完全再血管化和有良好的围术期管理,再次CABG可达到与首次手术同样的效果。     

国人桥血流搏动指数的研究

目的　研究冠状动脉旁路移植术 (CABG)国人桥血流的搏动指数 (PI值 )合适的范围。方法　将 35 7例CABG病人分为二组 ,不停跳 (OPCAB)组 2 6 3例 ,停跳 (CCABG)组 94例。常规用原位带蒂左乳内动脉 (LIMA)与左前降支 (LAD)吻合 (LIMA组 ) ,其余桥使用大隐静脉 (SV组 )。SV吻合口多于 2个时采用序贯式吻合 ,近端吻合于升主动脉。移植完毕动脉血压稳定后 ,用直径为 2～ 3mm超声微探头直接测量LIMA和SV桥的平均血流量、收缩期和舒张期血流量以及PI值 ,并记录血流波形。确定PI值“合适”的标准 :舒张期血流波形良好 ;平均血流量大于 10ml min ;术中及术后CK MB、cTnI在正常范围和无ECG改变及手术后临床症状改善等。结果　各组测量桥血流时血压差异无显著性。共测量LIMA 35 7根 ,SV 32 4根。LIMA之PI值 :OPCAB为 2 4 9± 0 91,CCABG为 2 39± 1 16 ;SV之PI值 :OPCAB为 2 6 8±1 35 ,CCABG为 2 5 9± 1 4 2 ;各组间PI值差异无显著性 (P >0 0 5 )。用全部PI值计算出总体平均值为2 5 6± 2 35 (95 %置信度 )。结论　国人冠状动脉旁路移植术桥血流的PI的参考值范围为小于 5。     

冠状动脉旁路移植术后移植血管狭窄的危险因素分析

目的探讨冠状动脉旁路移植术（cABG）后移植血管狭窄的危险因素,为临床CABG术后移植血管狭窄的防治提供依据。方法回顾性分析1999年1月至2007年12月间197例cABG术后行选择性血管造影患者的临床资料,CABG术后按选择性血管造影检查是否有移植血管狭窄,将197例患者分为两组,狭窄组（n=87）,非狭窄组（n=110）。采用t检验、Χ^2检验和多因素logistic回归分析影响移植血管狭窄的危险因素。结果狭窄组的87例患者血管造影显示存在不同程度的移植血管狭窄,累及吻合口321处,其中远端吻合口305处,近端吻合口16处。单因素分析结果表明,合并糖尿病、血脂异常、远端吻合口吻合于右冠状动脉系统、靶血管狭窄〈70%、靶血管管径〈1．5mm、应用大隐静脉桥和非体外循环CABG等因素与CABG术后移植血管狭窄有关。logistic回归分析结果发现：糖尿病（OR=3．654）、血脂异常（OR=2．625）、靶血管狭窄〈70％（OR=1．763）、靶血管管径〈1．5mm（OR=1．337）、远端吻合口位于右冠状动脉系统（OR=1．694）和大隐静脉桥（OR=1．652）是CABG术后移植血管狭窄的独立危险因素。结论糖尿病、血脂异常、靶血管狭窄〈70％、靶血管管径〈1．5mm、远端吻合口位于右冠状动脉系统和大隐静脉桥是CABG术后移植血管狭窄的危险因素。     

冠状动脉旁路移植术后旁路血管狭窄影响因素分析

目的总结冠状动脉旁路移植术(CABG)后旁路血管造影特点,分析相关因素对旁路血管通畅率的影响,并探讨提高旁路血管通畅率的方法。方法2004年4月至2006年4月间CABG术后平均间隔(46.4±39.1)个月,因心绞痛复发再入院行冠状动脉造影(CAG)病人149例,男120例;平均年龄(61.0±10.1)岁。共444支旁路血管,其中左乳内动脉(LIMA)131支,大隐静脉(SV)295支,左桡动脉(RA)15支,右乳内动脉(RIMA)3支。旁路血管造影完全闭塞或狭窄≥75%视为旁路血管病变。结果本组65.1%(97/149例)病人有旁路血管病变。31.1%(138/444支)旁路血管发生病变。LIMA闭塞5.3%(7/131支),狭窄(≥75%)6.9%(9/131支);SV旁路血管闭塞31.9%(94/295支),狭窄7.5%(22/295支);RA旁路血管闭塞33.3%(5/15支);RIMA旁路血管闭塞33.3%(1/3支)。LIMA旁路血管的通畅率明显优于SV。不同靶血管的SV旁路血管通畅率有明显差别。吻合口以远冠状动脉口径(runoff)≥2.0 mm的旁路血管通畅率明显高于<2.0mm者,尤其是SV旁路血管。近端冠状动脉狭窄程度对LIMA-前降支的通畅率影响明显,而对主动脉-SV-后降支通畅率影响不明显。序贯吻合及非体外循环CABG对旁路血管通畅率无明显影响。结论CABG术后旁路血管病变比较常见,是造成术后心绞痛复发的重要原因。不同旁路血管、不同靶血管、runoff大小、近端冠状动脉狭窄程度均明显影响旁路血管通畅率。手术技术不当是术后早期旁路血管病变的主要原因。改进手术技术,术后早期足量抗血小板药物及强化降脂治疗是提高旁路血管通畅率的关键。     

冠状动脉旁路移植术瞬时测血流量技术的临床应用

目的　总结瞬时测血流量 (TTFM)技术在冠状动脉旁路移植术 (CABG)中的应用经验 ,探讨异常血管桥瞬时血流量技术参数特点、发生原因及处理方法。方法　 2 0 0 1年 9月至 2 0 0 2年 5月 ,连续对5 0例不停跳冠状动脉旁路移植及 40例常规体外循环下旁路移植者进行血管桥血流量测定 ,随机 30例进行左侧乳内动脉 (LIMA)血流量测定。结果　 30例LIMA离断后TTFM参数 :平均血流 (42 9± 33 0 )ml min ,弹力指数 (PI)值 1 0 0± 0 6 4,波形曲线为收缩期、舒张期双向血流 ,收缩期为主 ,实际平均血流为(37 4± 2 8 8)ml min ,相关系数为 0 98。 90例冠状动脉旁路移植TTFM参数 :LIMA到左前降支 (LAD)平均流量 (2 9 9± 9 5 )ml min ,平均PI值 2 47± 0 88。大隐静脉或桡动脉到回旋支系统平均流量 (33 7±17 5 )ml min ,PI值 4 0± 1 9;到右冠状动脉系统 ,平均流量 (31 5± 19 2 )ml min ,PI值 2 6± 1 3 ;到前降支及回旋支系统为双向血流 ,血流以舒张期为主 ,收缩期可形成负值 ;到右冠状动脉系统 ,收缩及舒张期为双向灌注 ,较少出现负值。TTFM技术提示 ,2 87支血管桥中有质量问题血管桥 6支 ,均手术证实并加以矫正。 90例病人均无围术期心肌梗死及其它严重并发症 ,无死亡。随访 2～ 10个月 ,病人无心绞痛及心肌     

冠状动脉左前降支狭窄程度与乳内动脉桥血流量的相关性研究

目的　了解非体外循环冠状动脉旁路术 (OPCAB)术中左前降支 (LAD)狭窄程度与左乳内动脉 (LIMA)桥血流量的相关性。　方法　将行OPCAB治疗的 16 7例患者 ,按LAD狭窄程度 (<75 %、75 %～ 95 %、>95 % )分为 3组 ,A组 31例、B组 6 2例、C组 74例 ,常规用LIMA与LAD吻合 ,吻合完毕时用即时超声血流探测仪直接测量并记录LIMA桥血流波形、平均流量、舒张期流量、收缩期流量、搏动指数 (PI)及平均动脉压 ,进行LIMA血流量的对比研究。　结果　 3组间平均动脉压差异无显著意义 (P >0 0 5 ) ;C组LIMA桥平均血流量 (2 8 3± 3 2 )ml/min ,舒张期流量 (5 5 1± 5 3)ml/min ,均显著高于A组 [(11 1± 1 2 )、(2 6 3± 2 8)ml/min]和B组 [(16 3± 1 6 )、(34 8± 3 2 )ml/min](P均 <0 0 1) ;B组平均流量、舒张期流量大于A组 (P <0 0 1、P <0 0 5 ) ;PI值C组小于其他两组 (P <0 0 1) ,B组小于A组 (P >0 0 5 ) ;而收缩期流量各组之间差异均无显著意义 (P >0 0 5 )。结论　OPCAB中 ,LAD狭窄程度越高 ,LIMA桥血流量越大 ,PI值越小 ,而收缩期血流量与狭窄程度无关。     

定量血流分数指导冠状动脉外科血运重建手术策略的研究

目的探讨术前应用定量血流分数(QFR)评估冠状动脉功能性狭窄程度, 指导冠状动脉旁路移植(CABG)血运重建策略的可行性。方法前瞻性纳入2019年1月至2020年9月期间在北京安贞医院心脏外科十一病房择期行单纯CABG的154例患者, 对冠状动脉造影目测提示狭窄的病变血管进行QFR分析, 获得病变血管功能性狭窄情况, 外科医师术前对QFR分析结果不知情。收集患者基线资料、围手术期相关数据及近期临床结局并总结分析。结果 1年后冠状动脉CTA显示, 功能性显著病变(QFR<0.8)血管的旁路移植血管闭塞率为5.5%, 非功能性显著病变(QFR≥0.8)血管的旁路移植血管闭塞率为15.6%。随访发现, 心绞痛分级在发生与未发生旁路移植血管闭塞的患者间差异无统计学意义。结论依据QFR分析的功能性非显著病变的冠状动脉发生旁路移植血管闭塞的风险高于功能性显著病变血管, 对于QFR提示阴性病变的冠状动脉, 动脉旁路移植血管发生闭塞的风险比静脉旁路移植血管更高。这一发现与临床预后并无明显关联, 非显著病变血管的旁路移植血管通畅或闭塞的患者均未发现过多心绞痛发作或冠状动脉重复干预的情况。QFR指导...     

A case of lateral origin of the left internal mammary artery

A 66 years old men, with left anterior descending coronary artery (LAD) stenosis and aortic valve stenosis, underwent coronary artery bypass grafting (CABG) to LAD with left internal mammary artery (LIMA) and aortic valve replacement. His postoperative course was uneventful. But, postoperative angiogram showed that his patent LIMA graft was originated from much lateral side of the left subclavian artery. Internal mammary artery is considered the most ideal graft for CABG, but its' anomality is not well known. We present this rare case with the anomalous origin of LIMA.     

Off-pump redo coronary artery bypass grafting

BACKGROUND: Conventional redo coronary artery bypass grafting is associated with significant morbidity. The danger of reoperation is mainly in reopening the sternum and in the manipulation of the heart and the old grafts. Therefore, off-pump redo coronary artery bypass grafting with a patient-specific approach in selected cases seems an ideal technique. METHODS: Between October 1995 to September 1999, 50 patients with mean age of 61.8+/-8 years underwent reoperative coronary artery bypass grafting without cardiopulmonary bypass. Isolated left internal mammary artery (LIMA) to left anterior descending artery (LAD) anastomosis was carried out in 25 cases through left anterior minithoracotomy. In 1 patient LIMA was grafted on a previous vein graft to LAD, which was critically stenosed proximally but distal anastomosis was patent. In another case LIMA was grafted to Ramus intermedius branch. Midsternotomy approach was used to carry out LAD and right coronary artery grafting in 21 cases. In 2 patients a posterolateral thoracotomy approach was used to bypass obtuse marginal branches without cardiopulmonary bypass; in these cases proximal anastomosis was performed on the descending aorta. RESULTS: Mortality rate was 4% (2 deaths). Two patients sustained perioperative myocardial infarction. No patient was reexplored for hemorrhage and 38 patients did not require homologous blood transfusion. Sixteen patients underwent check angiogram and all of them were found to have patent redo grafts. Cardiac recovery room stay was 22+/-7 hours and hospital stay 5+/-2 days. CONCLUSIONS: In selected patients, reoperative coronary artery bypass grafting can be performed without cardiopulmonary bypass with a low perioperative morbidity and mortality and satisfactory graft patency.     

Various clinical scenarios leading to development of the string sign of the internal thoracic artery after coronary bypass surgery: the role of competitive flow,a case series

Background  

The left internal mammary artery (LIMA) is the choice for grafting of the left anterior descending coronary artery (LAD). One possible mechanism of the rare graft failure involve the presence of competitive flow.     

Treatment of double vessel coronary artery disease by totally endoscopic bypass surgery and drug-eluting stent placement in one simultaneous hybrid session

Hybrid coronary artery revascularization is a combination of minimally invasive coronary artery surgery and catheter-based coronary intervention. Hybrid procedures enable adequate revascularization of patients with multivessel coronary artery disease without complete opening of the chest and with the advantage of the most durable option, a left internal mammary artery (LIMA) graft is placed to the left anterior descending (LAD) artery. The hybrid concept is gaining renewed interest because totally endoscopic LIMA to LAD placement has become feasible and because drug-eluting stents in non-LAD targets may be competitive even for arterial bypass grafts. Simultaneous hybrid procedures would be desirable. We report on a case in which robotic totally endoscopic LIMA to LAD grafting using the da Vinci telemanipulation system was combined with placement of a rapamycin coated stent to the right coronary artery in one single procedure.     

Competitive flow between a vein and an arterial graft at transit-time flow measurement

We report the intraoperative finding, at a transit-time flow measurement, of competitive flow between a venous and an arterial graft in a 72-year old woman who underwent uncomplicated coronary artery bypass grafting 3. The blood flow in the left internal mammary artery (LIMA) improved only after temporary occlusion of the saphenous vein graft (SVG) anastomosed to the first diagonal (D1), demonstrating the presence of competitive flow from the SVG-D1 anastomosis into the LIMA-left anterior descending coronary artery (LAD) system. Interestingly the two target vessels suffered from separate critical lesions. The patient's haemodynamics remained stable throughout and no further action was taken. Her recovery was uneventful and the patient was discharged home on postoperative day 6. This case raised questions about the cost benefit of grafting a diagonal target even when it appeared to be disconnected from the LAD on a coronary angiogram.     

Assessment of left mammary artery grafts (LIMA) to left anterior descending artery (LAD) after off-pump coronary artery bypass grafting by color Doppler.

BACKGROUND: Off-pump coronary artery bypass grafting (OPCAB) on a beating heart with a LIMA graft to the LAD is established for patients with one vessel disease. The aim of the study was to assess the LIMA patency noninvasive by transcutaneous duplex ultrasound. METHODS: 25 patients (16 male, 9 female, mean age 58+/-13 yr) with LIMA grafts to LAD by OPCAB procedures were studied 7-20 days after surgery. Doppler velocity parameters were measured by use of a 7 MHz transducer placed in left intercostal space. The conventional coronary angiographies performed showed the LIMA graft patent. RESULTS: In all cases a typical biphasic pattern of blood flow was recorded with forward flow in both systole and diastole respectively. Under basal conditions the mean peak velocities in systole were 0.36 m/s and the mean peak velocities in diastole were 0.27 m/s with a mean systolic/diastolic ratio of 1.33. CONCLUSION: Transcutaneous Doppler ultrasound is useful in the detection of the LIMA graft flow. This non-invasive technique may find applications for routine postoperative follow-up of patients with LIMA grafts.     

胸腔镜辅助与前正中开胸非体外循环下冠状动脉旁路移植术乳内动脉桥猪模型的对比研究

目的建立一种能模拟胸腔镜辅助非体外循环下冠状动脉旁路移植术乳内动脉桥的家猪模型,与前正中开胸手术进行对比研究。方法 16头家猪,随机分为2组,VACAB组为胸腔镜辅助组,采用胸腔镜辅助的方法行非体外循环下左乳内动脉-前降支(LIMA-LAD)旁路移植术,MTCAB组为前正中开胸组,采用前正中开胸的方法行非体外循环下左乳内动脉-前降支旁路移植术。比较两组手术时间、左乳内动脉(LIMA)游离时间,LIMA-LAD吻合时间,和不同时间点的血液监测指标:肌酸磷酸激酶(CK)、磷酸肌酸激酶同工酶(CK-MB)、肌钙蛋白I(cTnI)。结果 VACAB组的手术时间、LIMA游离时间及LIMA-LAD吻合时间均较开胸组延长,且差异具有统计学意义。两组动物LIMA桥流量差异无统计学意义。两组之间CK、CK-MB、cTnI的差异无统计学意义。结论电视胸腔镜辅助非体外循环下冠状动脉旁路移植术是一种现实可行、效果良好的微创手术,采用动物模型进行VACAB训练有助于临床实践。     

Fate of the graft and native vessel following endarterectomy of the left anterior descending coronary artery.

In 16 patients who underwent endarterectomy of the left anterior descending (LAD) coronary artery combined with saphenous vein bypass grafting between Aug. 1, 1976 and July 31, 1978, the results of preoperative and postoperative angiography were comparable. Most patients had obstruction or severe stenosis of the proximal LAD coronary artery together with a poor runoff as demonstrated angiographically. Eighteen vein grafts were placed in the LAD artery and 15 (83%) were satisfactorily patent. Six of 18 grafted arterial segments became occluded distal to the site of graft insertion, but in most cases there was sufficient proximal runoff to maintain graft patency. In this study intraoperative measurements of graft flow were predictive of graft or distal vessel patency, or both. Careful postoperative assessment of the results of this technique seems warranted.