Early results of off-pump coronary artery bypass

Objective: The purpose of this study is to compare the operative results of off-pump coronary artery bypass (OPCAB) and on-pump (conventional) coronary artery bypass (CCAB), to clarify qualitative problems and whether OPCAB is less invasive or not. Methods: OPCAB was consecutively performed in 63 patients and CCAB in 63 patients between July 1998 and December 2003. Results: The mean number of bypass grafts was 2.43 ±0.82 in the OPCAB group and 2.70±0.71 in the CCAB group (p=0.096). In-hospital mortality was 0% in the OPCAB group and 3.2% in the CCAB group. The incidence of perioperative myocardial infarction was 0% in the OPCAB group and 3.2% in the CCAB group. The incidence of postoperative major complications was significantly lower in the OPCAB group than in the CCAB group (OPCAB group=4 complications, CCAB group=13 complications). Cerebrovascular accidents occurred in 1.6% of patients in both groups. The incidence of sternal infection or mediastinitis was 0% in the OPCAB group and 3.2% in the CCAB group. The early patency rate of graft was 94.0% in the OPCAB group and 92.8% in the CCAB group, and was not significantly different (p=0.822). Conclusion: Operative mortality and major complications after surgery in OPCAB were lower than that in CCAB. The early patency rate in OPCAB was as good as that in CCAB. It is considered that OPCAB is less invasive and the quality of bypass in OPCAB is as good as that in CCAB.     

Surgical considerations in off-pump coronary artery bypass grafting

Off pump coronary artery bypass grafting remains an important technique particularly in the care of high-risk patients. Consistently successful adoption of this technique requires a cooperative team approach and standardization across all phases of patient care. This review describes our approach to off pump coronary surgery.     

Early results of complete off-pump coronary revascularization using left internal thoracic artery with composite radial artery

Objective: Off-pump coronary artery bypass (OPCAB) using the left internal thoracic artery (LITA) with a composite radial artery (RA) was employed for arterial revascularization in order to minimize neurological complication. Methods: Sixty-one patients underwent OPCAB using the LITA with a composite RA. Angiography was performed in all patients at two weeks postoperatively. Results: The mean number of distal anastomoses was 3.2±0.4 A Y-composite graft was used in 55 patients, and K-composite graft was used in the other 6 patients. There was no hospital death, no neurological complication nor deep sternal infection Furthermore, there was no episode of perioperative myocardial infarction nor hypoperfusion syndrome. Patients have been angina-free during a mean follow-up period of 1 year. The graft patency of the LITA to the left anterior descending artery (LAD) was 100% (61/61 anastomoses). The RA became occluded in 4 patients, and the patency rate was 95.6% (130/136 anastomoses). String or coronary-coronary bypass resulting from flow competition was observed in the LITA of 6 patients and in the RA of 13 patients. The string of the LITA occurred in the segment distal from the anastomosis with the composite RA. The string or coronary-coronary bypass was observed more often in cases in which the recipient coronary artery had less than 75% stenosis. Conclusion: OPCAB using only the LITA with a composite RA can be successfully and safely performed in patients with multivessel disease. Late postoperative follow-up of the flow competition is necessary to delineate the significance of flow competion.     

Perioperative myocardial infarction in patients undergoing off-pump coronary artery bypass grafting

Two patients in whom myocardial infarction in the inferior wall occurred after off-pump coronary artery bypass grafing (OPCAB) are described. In both patients, the right coronary artery had no critical lesion and was not grafted. There was no ischemic episode during operation. Coronary artery spasms and/or intracoronary thrombus formation may have been causes of these events. To our knowledge, this is the first report on perioperative myocardial infarction in OPCAB.     

Anaesthesia for off-pump coronary artery bypass grafting

Achieving surgical revascularization of the heart, while avoiding the insult of cardiopulmonary bypass, is particularly desirable in specific high-risk patient groups. The relatively recent advances in surgical technique allowing high-quality grafting without mechanical arrest have led to an increase in popularity of off-pump coronary artery bypass surgery. Nonetheless, operating on the beating heart, manipulating it and purposely inducing ischaemia, invariably has significant haemodynamic consequences which must be carefully yet aggressively managed. To compound the situation, the intraoperative monitoring typically employed to evaluate cardiac function, such as electrocardiography and echocardiography, are of limited efficacy at crucial moments in the procedure. It is therefore essential that the anaesthetist is able to assimilate information from a multitude of sources in order to safely navigate the patient through a period of continually changing cardiovascular stress.     

Anaesthesia for off-pump coronary artery bypass grafting

Achieving surgical revascularization of the heart, while avoiding the insult of cardiopulmonary bypass, is particularly desirable in specific high-risk patient groups. The relatively recent advances in surgical technique allowing high-quality grafting without mechanical arrest have led to an increase in popularity of off-pump coronary artery bypass surgery. Nonetheless, operating on the beating heart, manipulating it and purposely inducing ischaemia, invariably has significant haemodynamic consequences which must be carefully yet aggressively managed. To compound the situation, the intraoperative monitoring typically employed to evaluate cardiac function, such as electrocardiography and echocardiography, are of limited efficacy at crucial moments in the procedure. It is therefore essential that the anaesthetist is able to assimilate information from a multitude of sources in order to safely navigate the patient through a period of continually changing cardiovascular stress.     

非体外循环冠状动脉搭桥术的近期疗效评价

目的　分析非体外循环 (OPCAB)与常规体外循环下冠状动脉搭桥术 (cCABG)后监护特点和近期疗效。　方法　比较OPCAB组 (6 0例 )和cCABG组 (6 2例 )术后引流量和输血量、血管活性药物的使用、一般监护治疗和恢复情况及近期临床疗效。　结果　OPCAB组术后引流量小于 4 0 0ml的例数明显多于cCABG组 (χ2 =7.316 ,P <0 .0 1) ,而大于 80 0ml的例数明显少于cCABG组 (χ2 =13.2 16 ,P <0 0 0 1)。OPCAB组术后未输血例数明显多于cCABG组 (χ2 =37.793,P <0 0 0 1)。OPCAB组使用硝普钠的例数较cCABG组多 (χ2 =12 .0 0 6 ,P <0 .0 0 1) ,而使用多巴胺的例数明显少于cCABG组 (χ2 =32 .198,P<0 .0 0 1) ,且未使用多巴酚丁胺。OPCAB组术后辅助通气 (5 .9± 3.3)h ,心电监测 (4.8± 1.7)d ,术后(18 1± 4 .1)h坐起 ,(15 .2± 5 .0 )h开始进食 ,平均 (2 .3± 0 .9)d拔除引流管 ,均明显短于cCABG组 (t =14 .0 2 5 ,5 .4 71,5 .791,8.95 3,5 .80 0 ,P <0 .0 1)。OPCAB组死亡 1例 ,围术期心肌梗死 1例 ,心律失常 4例 ,使用IABP 1例 ,较cCABG组少 ,但差别均无显著性 (χ2 =1.776 ,1.776 ,1.937,1.77,P >0 .0 5 )。　结论　OPCAB术后循环稳定 ,创伤小 ,恢复快 ,体现出微创手术的优越性     

Aortic connector for coronary revascularization in a patient with Takayasu''s disease

Takayasu's disease affects the aorta and its major branches including coronary arteries, some of which may require coronary artery bypass grafting (CABG). However, calcification of the aorta affected by Takayasu's disease often makes proximal anastomosis of a vein graft very difficult. In addition, since the major branches of the aortic arch are also frequently affected by it, the internal mammary arteries are unsuitable for use in CABG. We report a 60-year-old woman with stenosis of the left main coronary artery and heavy aortic calcification caused by Takayasu's disease whose severe angina was successfully relieved by off-pump CABG using mechanical aortic connectors for proximal vein graft anastomoses.     

Use of an audible ultrasonic flowmeter to locate deeply buried coronary arteries for off-pump coronary artery bypass grafting

In patients with coronary arteries that are deeply buried in the myocardium and fat, it is difficult and sometimes risky to expose them for off-pump coronary artery bypass grafting (OPCAB), leading to unavoidable conversion to conventional coronary artery bypass grafting (C-CABG) to ensure their safety. We have developed a new search procedure for these coronary arteries using a dedicated ultrasonic flowmeter with a small tip probe for OPCAB. This technique enables the identification of intramuscular and intra-fat coronary arteries that are less diseased and thus more suited for bypass surgery instead of switching to C-CABG. We believe this procedure will not only improve the quality of OPCAB but also expand its indication.     

Coronary occlusion using bi-directionally stretched elastic sutures during off-pump coronary artery bypass grafting

Objective: Off-pump coronary artery bypass grafting may be partly invasive, particularly to the coronary endothelium that is snared. Efficacy of a simple technique to occlude a coronary artery with elastic sutures bi-directionally stretched just beneath the artery was evaluated.Methods: Test subjects were eighteen adult mongrel dogs weighing 20–30 kg. After systemic heparinization (150 U/kg), the mid-left anterior descending artery (mid-LAD) was exposed with a stabilizer applied and snared using non-elastic sutures (n=6) or elastic sutures (n=6), or occluded with elastic sutures bi-directionally stretched (n=6). The left internal thoracic artery (LITA) was anastomosed to the mid-LAD with humidified gas insufflation. After completion of the anastomosis, the mid-LAD was observed endoscopically through the LITA. The coronary endothelium was also observed by a scanning electron microscope (SEM) after perfusion fixation.Results: Bleeding at the anastomotic site with the coronary artery occluded by bi-directionally stretched elastic sutures was observed. However, all anastomoses were done successfully with the aid of humidified gas insufflation. Coronary endoscope showed that the lumens snared with non-elastic sutures were collapsed with folds and often with clots. Coronary arteries snared with elastic sutures appeared similar to the arteries snared with non-elastic sutures endoscopically, but with less clots. In the case of coronary occlusion with bi-directionally stretched elastic sutures, the lumens were occluded in a flattened linear fashion without clots. SEM showed endothelial injuries with blood cells deposited when non-elastic sutures were used. When elastic sutures were used for snaring, endothelial injuries were ameliorated with less blood cells deposited, which were further decreased when elastic sutures were bi-directionally stretched.Conclusion: The coronary artery can be effectively occluded by bi-directionally stretched elastic sutures with minimal endothelial damage.     

舒芬太尼在非体外循环冠脉搭桥术应用中的临床研究

目的 观察舒芬太尼在非体外循环冠状动脉搭桥手术应用中的安全性和有效性.方法 择期行OPCABG病人54例,被随机分成两组,舒芬太尼组和芬太尼组,每组27例,麻醉诱导应用丙泊酚1 mg/ks～2 ms/ks,同时分别静注舒芬太尼0.5 μg/ks～1μg/kg,或芬太尼4 μg/ks-8 μg/ks,同时吸入安氟醚维持麻醉,持续输注舒芬太尼0.08 μg·ks-1min-1,或芬太尼0.6 μg·ks-1·min-1.记录各组气管插管、切片、麻醉维持和拨除气管导管各时间的收缩压和舒张压.结果 在气管插管过程中,浅麻醉反应的病人数舒芬太尼组明显低于芬太尼组,在气管插管切皮,麻醉维持和拔管期间,芬太尼组收缩压、舒张压明显高于舒芬太尼组,术后清醒和拔管时间两组病人无统计学差异.结论 舒芬太尼的麻醉效果优于芬太尼,舒芬太尼能提供术中更稳定的血液动力学.     

Efficacy of off-pump coronary artery bypass grafting for the patients on chronic hemodialysis

OBJECTIVE: Coronary artery bypass grafting (CABG) under a beating heart is reported to be less invasive and promise earlier recovery. This study was performed to evaluate the efficacy of off-pump CABG in patients with end-stage renal failure. METHODS: Isolated CABG was performed on 40 hemodialysis patients at Shin-Tokyo Hospital Group between September 1, 1993, and December 31, 2000. Among them, off-pump CABG was performed in 16 and on-pump CABG in 24. Their preoperative, perioperative, and follow-up data were retrospectively collected. RESULTS: Patient's demographics and coronary risk factors were similar in off-pump and on-pump groups. The mean number of bypass grafts was 1.9 +/- 1.1 in the off-pump group and 2.8 +/- 1.1 in the on-pump group (P < 0.05). Blood transfusion was significantly less frequent in the off-pump group than in on-pump group. Postoperative complications were more frequently observed in the on-pump group (7.1% off-pump vs 25.0% on-pump). There were two hospital deaths in the on-pump group and none in the off-pump group. Postoperative intubation time, ICU stay, and hospital stay were significantly shorter in the off-pump group than in the on-pump group. Although follow-up period was short (1.1 +/- 0.7 years), no cardiac events occurred in the off-pump group. CONCLUSIONS: Off-pump CABG for hemodialysis patients is safe and useful and it enables early recovery. Postoperative cardiac events were controlled effectively during the short period of follow-up.     

Off-pump coronary artery bypass combined with abdominal aortic aneurysm repair in an 88-year-old male

We present the case of an 88-year-old patient who underwent off-pump coronary artery bypass using an aortic connector followed by repair of an abdominal aortic aneurysm to reduce surgical invasiveness. This approach merits consideration for high-risk patients.     

Physiological comparison of off-pump and on-pump coronary artery bypass grafting in patients on chronic hemodialysis

Objectives: Despite the long-term benefit, the operative results of conventional coronary artery bypass grafting for chronic hemodialysis patients remain unsatisfactory. The efficacy of off-pump coronary artery bypass grafting for hemodialysis patients is yet to be determined. The purpose of this study was to investigate the postoperative physiology of off-pump coronary artery bypass grafting for hemodialysis patients. Methods: Twenty-five hemodialysis cases who underwent isolated coronary artery bypass grafting were reviewed. Fifteen of these patients underwent off-pump coronary artery bypass grafting (off-group) and 10 underwent on-pump coronary artery bypass grafting (on-group). Comparisons were made in cardiac function (cardiac index and stroke volume index), respiratory function (AaDO₂), hemodialysis management (blood urea nitrogen, creatinine, right atrial pressure, pulmonary wedge pressure), and bleeding tendency (postoperative blood loss and blood transfusion). Results: There was no operative mortality, but 3 major postoperative complications occurred (2 sternal wound infections in the off-group and 1 pneumonia in the on-group). There was no difference in cardiac index or stroke volume index. AaDO₂ was significantly lower in the off-group. Plasma concentrations of blood urea nitrogen and creatinine were similar between groups. Right atrial pressure was lower and pulmonary wedge pressure tended to be lower in the off-group. Postoperative bleeding and blood transfusion were similar between groups. Conclusion: Our study confirmed that off-pump coronary artery bypass grafting is feasible for hemodialysis patients. Physiologic data showed that off-pump coronary artery bypass grafting might be effective in preserving postoperative lung oxygenation.     

Perioperative plasma brain natriuretic peptide and cardiotrophin-1 in off-pump coronary artery bypass

Objective. It has been suggested that brain natriuretic peptide (BNP) and cardiotrophin-1 (CT-1) are associated with myocardial dysfunction. The present prospective study was designed to investigate perioperative changes of plasma levels of BNP and CT-1 in off-pump coronary artery bypass (OPCAB). Method. Forty-nine patients undergoing elective OPCAB were divided into three groups. Group I: no previous myocardial infarction; Group II: previous myocardial infarction more than 12 weeks; Group III: recent myocardial infarction within 4–8 weeks. Perioperative BNP and CT-1 levels were measured, and hematochemical parameters were also collected. Results. Higher preoperative BNP and CT-1 levels were found in group III as compared to those in group I. BNP levels increased after operation, and reached peak value at 3–7 days after the operation. However, the postoperative changes of BNP levels were not different among groups in any time points. CT-1 levels did not change significantly after the operation as compared to baseline. Conclusion. Higher BNP and CT-1 levels were associated with recent myocardial infarction. BNP elevated after OPCAB, but CT-1 showed no significant postoperative changes. Postoperative changes of BNP and CT-1 do not associated with cardiac function in OPCAB.