Off-pump coronary artery bypass

OBJECTIVES: Off-pump coronary artery bypass grafting (CABG) on the beating heart has become popular procedure in cardiac surgery and its initial results appeared favorable. We report our early and mid-term results of off-pump CABG performed at Shin-Tokyo Hospital. METHODS: Medical records of patients undergoing off-pump or conventional on-pump CABG from September 1, 1996, to August 31, 1999 were retrospectively reviewed. Patients underwent off-pump CABG were further classified into 2 groups; MIDCAB (Off-pump CABG for single vessel revascularization via a small skin incision) and OPCAB (off-pump CABG mainly approached via midline sternotomy) group. Their preoperative, perioperative, and follow-up data were collected and analyzed. RESULTS: Among a total of 995 cases of CABG, 194 cases were off-pump CABG (male/female 142/52, mean age 66.9). The mean number of distal anastomoses in off-pump CABG was 1.9 +/- 0.9 (1.0 +/- 0.0 in MIDCAB and 2.3 +/- 0.7 in OPCAB), which was significantly fewer than in on-pump CABG (3.6 +/- 1.1), with p < 0.0001. Intubation time (5.3 +/- 5.7 hours in off-pump CABG vs 13.1 +/- 24.2 hours in on-pump CABG), ICU stay (1.7 +/- 1.1 vs 3.2 +/- 3.0 days), and postoperative hospital stay (14.0 +/- 7.9 vs 18.1 +/- 12.1 days) in off-pump CABG were significantly shorter than in on-pump CABG (p < 0.0001). In the off-pump CABG group, there were no in-hospital deaths and 14 major complications, fewer than in on-pump CABG (8 hospital deaths and 114 major complications). Postoperative angiography before hospital discharge was conducted in 80 patients (41.2%) and showed 2 occlusions, giving a graft patency rate of 98.6% in the off-pump group. During follow-up (0.9 +/- 0.6 year) period, there were 5 non-cardiac deaths and 20 cardiac events in the off-pump group. The actuarial survival rate at 36 months was 94.6% for off-pump CABG, showing no significant difference from the rate for conventional CABG patients (95.2% at 36 month, p = NS) The event-free rate was 84.0% at 36 months in off-pump CABG patients; however, which was less favorable than on-pump CABG patients (88.0% at 36 months, p < 0.05). CONCLUSIONS: Both in-hospital and mid-term results for off-pump CABG patients were acceptable. Isolated CABG can thus be safely performed without cardiopulmonary bypass. Advances in coronary stabilization have contributed to these improved results. The observed long-term cardiac events may be related to incomplete revascularization.     

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.     

非体外循环下冠状动脉旁路移植术

目的 总结110例非体外循环心脏跳动下冠状动脉旁路移植术经验，探讨其手术适应证、优缺点及手术方法。方法 常温、全身麻醉，胸正中切口，非体外循环心脏跳动下，应用特殊心表固定器行冠状动脉旁路移植术，平均搭桥3．9支，血管桥为乳内动脉、大隐静脉及桡动脉。结果 全组无手术死亡，术后心绞痛症状消失。手术时间平均为210min，术后气管插管时间平均为4．8h。术后住院时间平均为10d，住院费用平均为4．4万元。其中3例术中出现不可逆血压过低、室颤而转为体外循环冠状动脉旁路移植术。结论 非体外循环心脏跳动下冠状动脉旁路移植术是一种安全、有效的治疗方法。特别适合于老年及心功能差的患者，可减少体外循环并发症，缩短术后住院时间，降低住院费用，但不能完全替代体外循环旁路移植术。     

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.     

Sequential bypass using the right gastroepiploic artery for coronary artery bypass grafting

OBJECTIVE: Since 1989, we have applied the right gastroepiploic artery (RGEA) as a third arterial conduit for coronary artery bypass grafting (CABG) and started to use sequential RGEA in 1992. We evaluated the feasibility and efficacy of sequential RGEA grafting in CABG. METHODS: From December 1990 to January 2000, 46 patients underwent CABG with sequential RGEA. There were 42 male and 4 female patients with a mean age of 59 +/- 8.1 years. Mean postoperative follow-up period was 70 months. RESULTS: The mean number of anastomoses was 3.7 per patient. Mean luminal diameter of the RGEA was 2.2 +/- 0.4 mm by preoperative angiography and 2.3 +/- 0.6 mm by intraoperative measurement. Patency of the sequential RGEA was 92%; proximal anastomosis 100%, distal anastomosis 86% (p = 0.01). The 5-year actuarial survival and cardiac event-free rate were 91% and 93%, respectively. CONCLUSIONS: Sequential bypass using the RGEA is feasible, with excellent early and long-term results. The indication for sequential RGEA, however, needs careful anatomical consideration of both the luminal diameter of the RGEA and proximal stenosis of the target coronary arteries.     

Sequential bypass using the right gastroepiploic artery for coronary artery bypass grafting

Objective: Since 1989, we have applied the right gastroepiploic artery (RGEA) as a third arterial conduit for coronary artery bypass grafting (CABG) and started to use sequential RGEA in 1992. We evaluated the feasibility and efficacy of sequential RGEA grafting in CABG.Methods: From December 1990 to January 2000, 46 patients underwent CABG with sequential RGEA. There were 42 male and 4 female patients with a mean age of 59±8.1 years. Mean postoperative follow-up period was 70 months.Results: The mean number of anastomoses was 3.7 per patient. Mean luminal diameter of the RGEA was 2.2±0.4 mm by preoperative angiography and 2.3±0.6 mm by intraoperative measurement. Patency of the sequential RGEA was 92%; proximal anastomosis 100%, distal anastomosis 86% (p=0.01). The 5-year actuarial survival and cardiac event-free rate were 91% and 93%, respectively.Conclusions: Sequential bypass using the RGEA is feasible, with excellent early and long-term results. The indication for sequential RGEA, however, needs careful anatomical consideration of both the luminal diameter of the RGEA and proximal stenosis of the target coronary arteries.     

Coronary artery and graft spasm after off-pump coronary artery bypass grafting

We report a case of a 52-year-old man with severe coronary artery and graft spasm after triple-vessel off-pump coronary artery bypass grafting. Emergent coronary angiography was performed to identify the location and severity of the spasm. Intracoronary injections of several vasodilators failed to relieve the spasm. Observational treatments including intra-aortic balloon pump and inotropic drugs to increase coronary flow were performed until the spasm resolved. The patient recovered and was discharged. A follow-up coronary angiography revealed patent native coronary artery and bypass grafts without evidence of residual spasm.     

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.     

The clinical outcome of off-pump coronary artery bypass surgery in the elderly patients

Objective: There has been a body of evidence showing that off-pump coronary artery bypass (OPCAB) may reduce morbidity and mortality in the elderly patients. We reviewed our experience, retrospectively, on elderly patients aged 75 years and older who were operated on using the OPCAB technique. We compared their outcome to a similar group of elderly patients who were operated on using conventional coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) during the same period of time. Methods: Registry data and patients' notes and charts were reviewed for 56 consecutive elderly OPCAB patients (age 78.5±3.5 years) and 87 consecutive CPB patients (age 77.2±2.4 years, P=0.01). Both groups had similar risk factor profiles: Parsonnet score 17.4±4.4 (OPCAB) versus 16.6±5.2 (CPB), P=0.19. We studied in detail their preoperative and postoperative data in order to compare the outcomes of both techniques. Results: The length of stay in the intensive therapy unit (ITU) was 35.4±52.9 h for OPCAB patients and 77.6±144.9 h for CPB patients (P=0.0008). No patient died within 30 days in the OPCAB group, whilst ten (11%) CPB patients (P=0.0066) died within 30 days. The incidence of serious complications (including pulmonary oedema, septicaemia, permanent stroke and renal dysfunction requiring haemofiltration or haemodialysis) was one (2%) in the OPCAB group and 11 (13%) in the CPB group (P=0.028). CPB patients required a significantly higher number ten (12%) of intra-aortic balloon pumps (IABP) inserted compared to only one patient (2%) in the OPCAB group who required IABP insertion (P=0.05). Nine (11%) CPB patients were re-operated on for bleeding compared to no OPCAB patient (0%) needing re-operation, P=0.011. Conclusions: Although the mean age of the OPCAB group was significantly higher than the CPB group, the OPCAB group showed a significant reduction in postoperative serious morbidity, ITU stay and mortality. We believe that such a conclusion may have some effect on the decision-making and cost-effectiveness when performing coronary bypass surgery on the elderly population.     

Reoperative coronary artery bypass grafting using a minimally invasive direct coronary artery bypass procedure

OBJECTIVE: Reoperative coronary artery bypass grafting with cardiopulmonary bypass tends to cause a higher mortality and morbidity than the primary operation. The purpose of this study was to discuss the effectiveness and safety of a minimally invasive coronary artery bypass procedure for patients who had previously undergone coronary artery bypass surgery. METHODS: We performed redo single coronary artery bypass grafting to the left anterior descending coronary artery in 9 patients and to the right coronary artery in 3 patients using minimally invasive cardiac surgery. The graft to the left anterior descending coronary artery was taken from the left internal thoracic artery in 5 patients, the right gastroepiploic artery in 3 patients, and from the saphenous vein in the other 1 patient. The graft to the right coronary artery was from the right gastroepiploic artery in all 3 patients. RESULTS: All grafts were patent. There was no major postoperative complication and no surgical or hospital death except one late death. CONCLUSIONS: In selected patients, we could safely and completely perform coronary artery bypass re-grafting to the left descending coronary artery or right coronary artery using a minimally invasive operation.     

The superiority of pulmonary function after minimally invasive direct coronary artery bypass

OBJECTIVE: We determined whether minimally invasive direct coronary artery bypass (MIDCAB) leads to excellent postoperative pulmonary function, and which contributes more to this--minithoracotomy or avoidance of cardiopulmonary bypass. METHODS: Pulmonary function 1 week before and 2 weeks after surgery was evaluated in 8 patients undergoing MIDCAB (Group M), 10 undergoing off-pump coronary artery bypass (Group O), and 12 undergoing conventional coronary artery bypass grafting (Group C). Parameters were adjusted by their predicted values and postoperative values were expressed as a ratio to preoperative ones. RESULTS: Only Group M maintained postoperative vital capacity and forced expiratory volume in 1 second close to the preoperative level and thus, showed significantly better recovery than Groups O and C. No significant difference was seen between Groups O and C. CONCLUSIONS: MIDCAB provides better recovery of pulmonary function early postoperatively than other procedures thanks to minithoracotomy rather than avoidance of cardiopulmonary bypass.     

冠脉旁路移植术中桡动脉的获取和应用

目的总结冠状动脉旁路移植术中桡动脉的获取方法和早期临床效果。方法22例冠状动脉旁路移植术患者,行量化Allen试验决定是否切取桡动脉。桡动脉伴随静脉一起切取,术中不直接接触桡动脉,严格避免夹镊桡动脉本身;离断后腔内注入肝素罂粟碱液,并将桡动脉置于该液中备用。共获取桡动脉22根,远端吻合至冠状动脉后降支、钝缘支及前降支,近端均吻合至主动脉。术后常规应用钙通道阻滞剂12个月。结果术后患者心绞痛消失,心功能显著改善,无围术期心肌梗死。无术中桡动脉痉挛现象,围术期无出血、栓塞合并症,无手臂缺血发生。结论桡动脉移植物可常规应用于冠状动脉旁路移植术;严格的“免触”技术和术后应用钙通道阻滞剂是保证桡动脉良好功能的关键。     

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.     

Pre-emptive stellate ganglion block increases the patency of radial artery grafts in coronary artery bypass surgery

Background:  We evaluated the role of pre-emptive stellate ganglion block (SGB) in preventing radial artery spasm and increasing radial artery graft patency in patients undergoing off-pump coronary artery bypass surgery.
Methods:  In this prospective randomized study, 100 patients were divided into two equal groups ( n = 50). In group A, SGB was achieved using 10 ml of ropivacaine and, in group B, SGB was not performed. Radial artery blood flow was measured pre- and intra-operatively. Post-operative clinical determinants (S–T segment elevation, use of inotropic agents, incidence of atrial fibrillation) were recorded. Early coronary angiography was performed.
Results:  According to blood flowmeter measurements, the radial artery blood flow was significantly increased in patients with SGB. The incidence of atrial fibrillation, the need for inotropic agents and S–T segment elevation were all decreased in the SGB group. Angiographic intervention revealed that the incidence of graft spasm was also lower in the SGB group.
Conclusion:  Pre-emptive SGB is an effective method for increasing radial artery blood flow and preventing radial artery spasm. Complications related to radial artery spasm may be decreased and patients may have a more comfortable post-operative period with this method.     

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.     

64排CT对冠状动脉旁路移植术后桥血管病变的诊断研究

目的 评价64排螺旋CT血管造影(MSCTA)对冠状动脉旁路移植术(CABG)术后桥血管病变诊断的准确性.方法 2005年7月至2007年4月,共228例患者于CABG术后复查64-MSCTA,其中31例患者(82支桥血管)因有心绞痛或CT结果提示桥血管损害,进一步行冠状动脉造影(CAG).结果 所有桥血管均获得评价.64-MSCTA共发现13支桥血管闭塞,均得到CAG证实.CAG发现15支桥血管严重狭窄,64-MSCTA发现14处,漏诊1处,误诊1处.64-MSCTA诊断冠状动脉桥狭窄的灵敏度、特异度、阳性预测值、阴性预测值和与CAG符合率分别为93.3%、98.1%、93.3%、98.1%和97.1%;诊断桥血管病变的灵敏度、特异度、阳性预测值、阴性预测值和与CAG符合率分别为96.4%、98.1%、96.4%、98.1%和97.6%.结论 64-MSCTA可以准确评价术后桥血管通畅情况.     

Current status of coronary artery bypass grafting

The number of cases of coronary artery bypass grafting (CABG) reached more than 21 000 in Japan in 2002, and the operative mortality decreased to less than 1%, including emergency operations. The annual number of CABGs in Japan declined 17% after 2003 to 18 000 cases in 2005 owing to unrestricted percutaneous coronary intervention (PCI) with drug-eluting stents. However, CABG is the best treatment for multivessel coronary artery disease based on the comparative data of PCI versus CABG. There have been two trends in CABG during the last decade. One is the widespread use of off-pump (OP) CABG, and the other is multiple coronary artery revascularization. In 2004 and 2005, approximately 60% of all isolated CABG procedures in Japan were performed without cardiopulmonary bypass. In a study of long-term outcomes comparing PCI with drug-eluting stents versus CABG with only arterial grafts, the latter was carried out in 52% of total cases and in 66% of OPCAB cases. OPCAB with multiple arterial grafts has become the standard CABG in Japan.     

Massive coronary spasm of the native coronary system after coronary artery bypass grafting: Two patients with different outcomes

We report the cases of two patients who developed a massive spasm of the native coronary system in the immediate postoperative period, following a coronary artery bypass grafting operation with different outcomes. The first patient was hemodynamic stable and it was manifested as ischemic electrocardiographic changes in different leads (ST elevation or depression). He was treated with intracoronary and intravenous administration of nitroglycerin and calcium channel blocker and had a favorable outcome. The second patient died due to multiorgan failure and hemorrhagic shock, after the implantation of a central venoarterial extracorporeal membrane oxygenation.     

冠状动脉旁路移植术后症状复发患者的旁路移植血管状态评估

目的总结冠状动脉旁路移植术后症状复发患者的临床特点,探讨并分析旁路移植血管造影检查结果.方法回顾性收集2008年1月至2018年12月间1136例冠状动脉旁路移植术后症状复发患者的临床资料.其中男868例,女268例;年龄(62.5±8.7)岁,≥65岁485例(42.7%).合并高血压852例(75.0%),高脂血症548例(48.2%),糖尿病524例(46.1%),有吸烟史713例(62.8%).结果患者旁路移植术后至症状复发(4.65±3.39)年.1073例(94.5%)表现为胸痛,146例(12.9%)旁路移植血管完全失功能,326例(28.7%)旁路移植血管完全通畅.共移植旁路血管3341根,其中失功能(狭窄、闭塞)1435(43.0%)根,263(25.5%)根为动脉旁路移植血管,1172(50.8%)根为静脉旁路移植血管.左乳内动脉旁路移植血管失功能率为22.8%(209/916),低于右乳内动脉、胃网膜右动脉、桡动脉和游离的乳内动脉.前降区失功能率(30.6%)远低于回旋区(52.7%)和右冠状动脉区(56.9%).596例(52.0%)接受经皮冠状动脉介入术再血管化治疗再发症状,其中526例(88.3%)在原位血管进行.结论冠状动脉旁路移植术后症状复发最常见为胸痛,症状复发患者的冠状动脉造影结果比较严重.再血管化治疗方式主要为PCI,原位血管是其主要手术部位.