二维多普勒评价药物对旁路移植术后和原位乳内动脉血流的作用

目的比较硝酸甘油及硝苯地平对原位右乳内动脉(rightinternalmammaryartery,RIMA)及冠状动脉旁路移植术后的左乳内动脉(leftinternalmammaryartery,LIMA)血流特性的影响,为冠状动脉旁路移植术后用药提供药理学的依据。方法对11例冠状动脉旁路移植术患者术后1周在胸骨旁左右第1肋间用4.5mHz和3.7mHz的多普勒传感器测定RIMA与LIMA的直径、时间流速积分和心输出量,并分别求出血流量、全身循环阻力及局部血管阻力,观察这些指标在舌下含服硝酸甘油及硝苯地平前后的变化。结果舌下含服硝酸甘油及硝苯地平能引起平均动脉压及全身循环阻力不同程度的下降(P<0.05),两药间的数值差异无统计学意义(P>0.05)。用硝苯地平后心输出量在增加,差异有统计学意义(P<0.05);用硝酸甘油后有增加,但差异无统计学意义(P>0.05)。用硝酸甘油后RIMA的直径增加,差异有统计学意义(P<0.05),而血流量及局部血管阻力无明显变化;用硝苯地平后RIMA的直径及血流量均明显增加,局部血管阻力下降,差异有统计学意义(P<0.05),且用硝苯地平后RIMA的血流量较用硝酸甘油后增加更明显,差异有统计学意义(P<0.05),相对应局部血管阻力下降更加明显,差异有统计学意义(P<0.05)。LIMA的直径及血流量在用硝酸甘油和硝苯地平后均明显增加,而用硝苯地平后增加更加显著,差异有统计学意义(P<0.05),局部血管阻力在用硝酸甘油和硝苯地平后明显下降,以硝苯地平为更显著,差异有统计学意义(P<0.05)。结论①硝酸甘油和硝苯地平对冠状动脉旁路移植术后的LIMA的作用是增加直径及血流量,减低局部血管阻力,而以硝苯地平作用更强;②原位RIMA只受硝苯地平的影响,说明硝苯地平扩血管作用更强;③两药增加血流量是通过扩张血管而不是增加时间流速积分发挥作用的。     

应用二维多普勒法对正常人内乳动脉血液动力学特征的研究

目的 :应用二维多普勒法对正常人内乳动脉血流特性进行测定和研究 ,旨在为冠状动脉旁路移植术后患者内乳动脉桥的血流特性提供一个简单、安全、有效、无创的定量测定方法和血流特性。　　方法 :分别用 7.5 MHz和 4.5 MHz的超声波血管探头测定 10 0名正常人两侧内乳动脉的直径 ,总血流量 (F) ,时间流速积分 (TVI)和心排血量 (CO)。两位医师分别测定各指标求得二者检查结果之间的相关性 (r)。　　结果 :两侧内乳动脉各指标的测定在检查者之间有良好的相关性 (r=0 .88)。上肢运动可引起明显的一过性的直径(16 % ) ,F(116 % )和 F/ CO的增加及局部血管阻力下降。　　结论 :二维多普勒法对原位内乳动脉的血流特性进行评价是可行的 ,结果是可重复的 ,其对评价内乳动脉血流的生理性变化特性是一种简单、有效、安全、无创的方法     

术前乳内动脉超声检查在冠状动脉旁路移植术中的应用价值

目的：探讨术前乳内动脉超声检查在冠状动脉旁路移植术中的应用价值。方法：回顾性分析2018年1月1日至12月31日在北京大学人民医院行冠状动脉旁路移植术（CABG）的281例患者临床资料，统计术前乳内动脉超声检查结果，比较左、右乳内动脉的各项超声检查指标（乳内动脉直径、血流量、搏动指数），并结合患者乳内动脉的使用及手术中乳内动脉桥的超声测量结果，进行统计学和临床分析。结果：本研究共纳入281例行CABG的患者，男性210例（74.7%），术前乳内动脉超声显示左、右乳内动脉直径分别为（1.95±0.15） mm和（1.97±0.17）mm(P=0.014)，血流量分别为（15.4±5.9）ml/min和（18.2±7.2）ml/min(P<0.001)，搏动指数分别为4.12±1.40和3.90±1.19(P<0.001)。术前乳内动脉超声发现乳内动脉血流异常3例。Pearson相关性分析显示原位左乳内动脉血流量与直径相关（r=0.319,95%CI:0.205～0.425,P<0.001），原位左乳内动脉直径、血流量与乳内动脉桥血管血流量不相关（r分别为0.049和0....     

主动脉内球囊反搏技术救治高危冠状动脉旁路移植术患者

目的探讨围手术期应用主动脉内球囊反搏（intra-aortic balloon pump,IABP）对高危冠心病患者冠状动脉旁路移植术（coronary artery bypass graft,CABG）患者救治的效果。方法回顾性分析IABP对42例CABG围手术期患者的临床反应、血流动力学以及病死率的影响。结果平均IABP辅助时间（87±16）h,辅助期间平均动脉压（MAP）明显升高,心率降低、心排血量指数增加,术中及术前使用可改善心脏不停跳冠状动脉旁路移植术过程中,心脏对稳定器压迫的耐受性,同时使心脏功能差的患者顺利脱离体外循环。34例康复出院,住院死亡8例,主要死亡原因为低心排血量综合征、多器官功能衰竭等。结论IABP是一种简单有效的循环辅助手段,心功能差的高危CABG患者应积极地放置IABP。     

中国常用动脉化冠状动脉旁路移植术的通畅率及疗效

目前冠状动脉旁路移植术通常采用一支乳内动脉加一支或多支大隐静脉作为桥血管,大隐静脉会逐渐粥样硬化而闭塞,动脉的通畅率远高于大隐静脉。左乳内动脉已常规应用于冠状动脉旁路移植术,同应用双侧乳内动脉相比,左乳内动脉加大隐静脉被认为是远期死亡、心脏事件的独立危险因素。乳内动脉用于左侧冠状动脉时通畅率一样;原位或复合桥移植时所有的乳内动脉通畅率相同,但吻合于主动脉时通畅率降低,所以原位乳内动脉通畅率高于游离乳内动脉。胃网膜右动脉和桡动脉宜吻合于近端狭窄严重者。双侧乳内动脉+胃网膜右动脉可避免触及主动脉,最大程度地减少脑部并发症的发生。70岁以下冠状动脉旁路移植术、预期寿命5年以上者,应选择双侧乳内动脉;60岁以下没有或很少合并症的冠状动脉旁路移植术患者可考虑全动脉化搭桥手术。     

主动脉内球囊反搏应用于冠状动脉旁路移植术的体会

目的探讨主动脉内球囊反搏（IABP）在冠状动脉旁路移植术的应用效果。方法对7例冠状动脉旁路移植术患者围术期应用IABP，监测使用IABP前和使用后2h、撤机前的血流动力学变化。结果使用主动脉内球囊反搏后，收缩压（SBP）、平均动脉压（MAP）、中心静脉压（CVP）、心排指数（CI）和每小时尿量均有明显改善（P〈0．05）。结论在冠状动脉旁路移植术中及时进行主动脉内球囊反搏，能够帮助高危患者平稳度过围术期。     

主动脉内球囊反搏在急诊冠脉搭桥术中的应用

目的总结主动脉内球囊反搏(IABP)在急诊冠状动脉旁路移植术(eCABG)中应用的临床经验,探讨此类手术应用IABP的时机选择和适应证。方法总结12例冠心病患者在IABP支持下,实施急诊冠状动脉旁路移植术的情况。结果1例术后5d撤除IABP,次日出现严重心律失常死亡;其余11例均在术后3～6d撤除IABP,恢复良好,痊愈出院。结论急诊冠状动脉旁路移植术风险较大,特别是严重的低心排导致手术效果更加不确定.在术前、术中应用IABP可以有效地改善心功能,提高手术成功率。     

乳内动脉在冠状动脉旁路移植术中的应用

为了探索国人应用乳内动脉做冠状动脉旁路移植术的近期临床效果,从94年10月至98年3月共60例冠心病人采用乳内动脉、桡动脉及大隐静脉做冠状动脉旁路移植术(CABG).大多数为三支病变及左主干病变.中低温及常温体外循环,经主动脉根部间断灌注冷血或温血停跳液心肌保护.强调在取乳内动脉时要格外小心,不要用器械钳夹乳内动脉,牵拉应轻柔.采用8-0 Prolene线做乳内动脉与前降支等做远端吻合.吻合完成后应将乳内蒂固定于心脏表面,减少吻合口张力.最后切开左上心包让乳内动脉走行平坦,无张力.平均搭桥支数为3.5根.术后死亡1例,死亡率1.7%.使用乳内动脉做CABC是安全有效的.59例病人心绞痛完全缓解,活动能力及生活质量明显提高.     

主动脉内球囊反搏治疗冠状动脉旁路移植术后严重低心排出量综合征的体会

目的:总结主动脉内球囊反搏(IABP)治疗冠状动脉旁路移植术(CABG)后严重低心排出量综合征(LCOS)的经验。方法:回顾2002至2007年我院心脏外科285例冠状动脉旁路移植术患者的临床资料,其中31例患者因术后发生严重低心排出量综合征应用IABP辅助。结果:31例患者IABP辅助时间(62.3±22.1)h,主要并发症为出血6例、感染5例、下肢缺血3例、死亡2例。结论:IABP是治疗CABG术后严重低心排出量综合征的有效措施,应及时放置避免并发症。     

冠状动脉旁路移植术中骨骼肌化胸廓内动脉的应用

目的 探讨骨骼肌化胸廓内动脉（ITA）用于冠状动脉旁路移植术的优越性。方法采用剪刀和钛夹将骨骼肌化的ITA游离，并将其用于冠状动脉旁路移植术。结果共游离ITA 61根，并顺利用于60例冠状动脉旁路移植术患者，平均获取时间为26．8min。骨骼肌化ITA平均血流量吻合前为86．5ml／min，吻合后为26.4ml／min。随访1～31个月，无心脏相关性死亡和事件发生。结论在冠状动脉旁路移植术中应用骨骼肌化的ITA和带蒂ITA一样安全、有效。     

Assessment of left internal mammary artery graft patency and flow reserve after minimally invasive direct coronary artery bypass.

Despite its merits, minimally invasive direct coronary artery bypass surgery (MIDCAB) has been criticized for variable left internal mammary artery (LIMA) graft patency rates, prompting the frequent use of postoperative LIMA angiography. Noninvasive transthoracic Doppler interrogation of LIMA grafts has recently been shown to have utility for assessing patency and flow reserve after conventional bypass surgery, but data after MIDCAB has been limited. The objective of this study was to assess LIMA graft anatomy and physiology in 54 patients after MIDCAB using angiography and noninvasive LIMA Doppler imaging. The right internal mammary artery (RIMA) was studied as a control. LIMA flow reserve in response to adenosine was evaluated in a subgroup of 18 randomly chosen patients with patent grafts. LIMA angiographic patency was 93%. Forty-four patients (81%) had obtainable LIMA Doppler data. Patent grafts had a diastolic dominant flow pattern with a peak diastolic/systolic velocity ratio of 1.3 +/- 0.6 and a percent diastolic time-velocity integral (TVI) of 70 +/- 11%. These data were significantly different than the RIMA control values of 0.2 +/- 0.1 and 30 +/- 10%, respectively (p <0.05). Occluded grafts had absent flow or a systolic dominant pattern. Adenosine-induced increases in LIMA peak diastolic velocity from 48 +/- 20 to 105 +/-28 cm/s (p <0.05 vs baseline) and diastolic TVI from 21 +/- 10 to 37 +/- 19 cm (p <0.05 vs baseline), yielding adenosine/baseline ratios of 2.4 +/- 0.9 and 2.0 +/- 0.7, respectively, which was consistent with normal flow reserve. The diastolic flow velocity reserve response was inversely related to baseline diastolic flow (r = -0.69). In conclusion, MIDCAB can be associated with a high rate of LIMA potency and favorable physiologic Doppler flow patterns. Correlation of these findings to long-term patient outcome after MIDCAB is warranted.     

Coronary revascularization surgery with arterial conduits. The technic, results and 4-year follow-up in 1023 consecutive patients

OBJECTIVE: The main objective of the present study was to analyze the in-hospital and mid term results obtained in 1,023 consecutive patients undergoing coronary artery bypass surgery (CABG) in whom a combination of arterial grafts was used: radial arteries (RA) and one or both internal mammary arteries (IMA). METHODS: From May 1995 to May 1998, 1,023 consecutive patients underwent CABG alone, using arterial conduits (AC) (one or two IMA and RA) for myocardial revascularization. The left internal mammary artery (LIMA) was employed as an "in situ" graft, and the right internal mammary artery (RIMA) as a free graft or "in situ" both in combination with the RA. The latter was connected to the LIMA through a T or Y anastomosis, or emerged directly from the ascending portion of the aorta. RESULTS: An average of 3.2 bypasses per patient were performed. The LIMA was used in 100% of the patients. The RIMA was used in 21.7% and the RA in 100% of the cases. Operative mortality was 2.5% (26 patients) and 32 (3.1%) suffered perioperative acute myocardial infarction. The first 62 patients were angiographically re-studied before discharge, and a 98.4% patency of the AC used was found. Mean follow up time was 25.0 +/- 9.6 months (range, 1 to 48 months). CONCLUSIONS: a) myocardial revascularization procedures using a combination of mammary and RA grafts are safe; b) in-hospital and mid term morbidity and mortality are not higher than those observed with saphenous vein grafts; c) it is possible to achieve complete myocardial revascularization with only AC, even in patients with impaired left ventricular function, and d) AC can be used in elderly patients.     

Skeletonized bilateral internal mammary arteries for total arterial myocardial revascularization

BACKGROUND: Bilateral internal mammary artery (IMA) grafting is associated with an improved long-term survival, low rates of recurrence of angina and late myocardial infarction. However, because of the inadequate length of the conduit, use of bilateral internal thoracic artery grafting occasionally is not suitable for complete revascularization. To overcome this limitation, extra length can be obtained by skeletonization of both IMAs. We decided to prospectively assess the safety of this technique. METHODS: One hundred patients with a mean age of 52.5 +/- 13.1 years underwent complete revascularization with skeletonized bilateral internal mammary arteries on cardiopulmonary bypass (CPB). The right internal mammary artery (RIMA) was used as a free graft connected to the in situ left IMA (LIMA) in 88 patients. A free LIMA was attached to in situ RIMA in 12 patients. The average number of grafts was 3.2 per patient (range: 2-4 grafts per patient). Mean left ventricular ejection fraction was 60% (range: 25-80%). RESULTS: No patient required reexploration for bleeding, and no patient died within 30 days after operation. On the basis of electrocardiographic changes, three patients sustained a perioperative myocardial infarction. One patient had a sternal wound infection. Mean follow-up was 24 months (range: 6-36 months). The actuarial survival rate was 99 +/- 1% at 3 years. No myocardial infarctions were reported during the follow-up. Three patients had recurrent angina with conduit occlusion diagnosed on coronary angiography. CONCLUSION: Complete myocardial revascularization with skeletonized bilateral internal mammary arteries is a safe and reliable technique with excellent early and mid-term results.     

Transthoracic Doppler echocardiographic comparison of left internal mammary grafts to left anterior descending coronary artery with ungrafted right internal mammary arteries in patients with and without myocardial ischemia by dobutamine stress echocardiography

To characterize Doppler flow patterns of the grafted left internal mammary artery (LIMA) in patients with and without dobutamine stress induced wall motion abnormalities in the graft distribution, we studied 29 patients who underwent coronary artery bypass surgery using LIMA grafts to the left anterior descending coronary artery (LAD). The ungrafted right internal mammary artery (RIMA) was used as a control. RIMA Doppler flow pattern was predominantly systolic in all patients. In patients without ischemia in the LAD distribution, LIMA flow was predominantly diastolic. In patients with ischemia, LIMA flow was predominantly systolic. In the grafted LIMA, a ratio of diastolic to systolic time-velocity integral of > 1.5 best showed absence of ischemia in the graft distribution. In summary, characterization of the Doppler flow pattern in the internal mammary arteries is feasible. In the grafted LIMA, ratios of diastolic to systolic flow are less in patients with an ischemic response in the subtended vascular bed than in those without ischemia.     

Double coronary revascularization using the internal mammary arteries. Mid-term results of 74 cases

This study reports our experience of 74 multiple coronary artery bypass, using either the two internal mammary arteries (IMA) (43 cases), or the left internal mammary artery (LIMA), alone for sequential bypass (31 cases). Comparison with a series of 200 patients operated upon in a previous period (1981-83), when the LIMA was used alone for single bypass, showed that post-operative mortality, post-operative infarction and mediastinitis were significantly more frequent with double bypass using the two IMA; similarly, the mid-term results seemed to be less satisfactory with the double IMA bypass technique. This difference was due to the fact that using the right and left IMA means longer dissection time, greater problems of haemostasis, stronger surgical trauma and prolonged exposure of the sternum, which is a source of infection. In addition, the right internal mammary artery (RIMA) being further away from the sites of coronary grafting lends itself less readily than the LIMA to this type of bypass, and it is often used for the right and marginal coronary artery which is less suitable for surgery. Using the LIMA alone for sequential bypass does not seem to produce more complications than using that vessel for single bypass. On the basis of the results obtained, we consider that the double IMA bypass should only be used when the internal saphenous vein bypass is contraindicated (past history of stripping, varices, fragile aorta forewarning of difficult grafting).(ABSTRACT TRUNCATED AT 250 WORDS)     

Direct coronary stenting through left and right internal mammary artery grafts

We describe a case of successful direct coronary stenting of two tight lesions, one at the site of the left internal mammary artery (LIMA) graft anastomosis with left anterior descending coronary artery and the other at the site of the anastomosis between the right internal mammary artery (RIMA) graft and the right coronary artery. To our knowledge, this is the first reported case of successful direct stent implantation through the LIMA and RIMA.     

Perioperative and clinical-angiographic late outcome of total arterial myocardial revascularization according to different composite original graft techniques

Total arterial myocardial revascularization (TAMR) is advisable because of the excellent long-term patency of arterial conduits. We present early and midterm outcomes of five different surgical configurations for TAMR. Between January 1998 and May 2004, 112 patients (aged 56.5 ± 4.5 years, 20% female) with three-vessel disease underwent TAMR. The internal mammary arteries (IMAs) were harvested in a sketelonized fashion. The surgical techniques for TAMR consisted in Y or T composite grafts (n = 88, 78%) constructed between the in situ right IMA (RIMA) and the free left IMA (LIMA) graft (n = 58) or the radial artery (n = 30) (RA) in three different configurations. The other techniques consisted in T- and inverted T-graft (n = 24, 22%) constructed between the RA conduit and the free LIMA graft in two different configurations. The mean follow-up time was 40 ± 23 months. Postoperative angiographic control was performed in 76/111 (70%) patients. Overall, 472 arterial anastomoses (average 4.2 per patient) were performed. One (0.9%) patient, undergoing the inverted T-graft technique, died on postoperative day 2. Another patient (0.9%), undergoing the λ-graft technique using both IMAs and RA, suffered a new myocardial infarction probably due to RA conduit vasospasm. One week after surgery, after the transthoracic echocardiographic Doppler with adenosine provocative test, the coronary flow reserve (CFR) at the LIMA and RIMA main stems were 2 ± 0.4 and 2.4 ± 0.3, respectively. At 12-month follow-up, after adenosine provocative test, the CFRs at the LIMA and RIMA stems were significantly higher than the values at 1 week after surgery within the same group; ^LIMACFR (1 week) 2.4 ± 0.3 (12 months) vs 2 ± 04 (1 week), P = 0.002; ^RIMACFR 2.58 ± 0.4 vs 2.4 ± 0.3, P = 0.001. The CFR at the RIMA main stem was higher in all measurements within the same group than in the LIMA main stem, but not significantly. In one patient undergoing the λ-graft technique using both IMAs, the RIMA was found to have a string sign. Postoperative angiography in 50 patients showed that the patency rate for the LIMA was 100%, for the RIMA 97.3%, and for the RA 96.7%. Angiography at 3-year follow-up in 76 patients documented excellent patency rates of the LIMA (97.4%), RIMA (95%), and RA (87%). Survival at 7 years was 92.5%, event-free survival 89.3%, and freedom from angina 94%. Total arterial myocardial revascularization using different surgical configurations is safe and effective. The use of composite arterial grafts provides excellent clinical and angiographic results, with a low rate of angina recurrence and late cardiac events. These configurations allow for complete arterial revascularization.     

Interventional treatment of the left subclavian in 2 patients with coronary steal syndrome

In patients with history of coronary artery disease angina pectoris is usually attributed to the progression of atherosclerotic lesions. However,in patients with previous coronary artery bypass graft operation(CABG) using internal mammary artery grafts,great vessel disease should also be considered. Herein we present two patients with history of CABG whose symptoms were suspicious for coronary ischemia. During cardiac catheterization reverse blood flow was observed from the left artery disease to the left internal mammary artery(LIMA) graft in both cases. After angioplasty and stent implantation of the left subclavian artery antegrade flow was restored in the LIMA grafts and both patients had complete resolution of symptoms.     

Collateralization of an occluded left internal mammary artery coronary bypass graft

The left internal mammary artery (LIMA) is frequently utilized in coronary artery bypass grafting (CABG); adequate visualization of the LIMA bypass graft during diagnostic angiography is critical for determination of myocardial blood supply. We present a novel case of angiography via a left transradial approach demonstrating an occluded LIMA coronary bypass graft with antegrade flow maintained via a collateral branch from the ipsilateral thyrocervical trunk. Given the prevalence of LIMA use in CABG, it is critical to be aware of unusual configurations, including collateralization of a proximally occluded LIMA graft as described in this report.     

Detection of patency of internal mammary artery grafts to the left anterior descending artery by transthoracic Doppler echocardiography

BACKGROUND: To determine whether a coronary artery bypass graft (CABG) is patent, we examined the flow of the left internal mammary artery (LIMA) to the left anterior descending artery (LAD) by transthoracic Doppler echocardiography (TTDE). PATIENTS AND METHODS: Eighty-seven patients with CABG (LIMA to distal LAD) were enrolled in the study. The flows from each subject were analyzed by three criteria: mosaic flow at the anastomosis site, distal anterograde flow (ante flow), and proximal retrograde flow (retro flow). RESULTS: On angiography, 79 grafts were patent and eight were not. TTDE study of 79 patent grafts demonstrated mosaic, ante, and retro flow in 63 (79.7%), 74 (93.7%), and 35 grafts (49.4%), respectively. The averaged diastolic peak velocity of ante flow was 26.3 +/- 11.0 cm/sec, significantly higher than that (4.8 +/- 7.1 cm/sec, P < or = 0.0001) in eight patients without patent grafts. These eight patients had no mosaic or retro flow and only three had ante flow. The accuracies to predict patency were 81.6%, 90.8%, and 49.4% for mosaic, ante, and retro flows, respectively. CONCLUSIONS: The existence of mosaic, retro, or sufficient ante flows strongly indicated the patency of LIMA to the LAD. When symptoms are possible to be derived from the occlusion of CABG to LAD, TTDE is a promising method to examine whether a LIMA to LAD bypass is patent.