Current status of coronary artery bypass grafting

The number of coronary artery bypass grafting (CABG) has reached more than 21,000 cases per year in Japan, and the operative mortality has decreased less than 1% including emergent operation. There are 2 trends in CABG. One is the revival and wide spread of off-pump CABG (OPCAB). The other is multiple arterial coronary revascularization. In 2004 and 2005, 60% of all CABG procedures in Japan were performed without cardiopulmonary bypass. For competition with percutaneous coronary intervention with drug eluting stents and better long-term outcomes, CABG with only arterial grafts was carried out in 52% of total cases and 66% of OPCAB cases. OPCAB with multiple arterial grafts has been becoming the standard CABG in Japan. We reviewed OPCAB and arterial CABG including new technology.     

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.     

Off-pump coronary surgery: how do the anesthetic considerations differ?

In recent years, there has been much interest in performing coronary artery bypass graft (CABG) surgery without the aid of cardiopulmonary bypass (CPB). Initial efforts focused on "minimally invasive" direct coronary artery bypass, wherein the left anterior descending artery is bypassed with an in situ left internal mammary artery graft through a small left anterior thoracotomy. A more widely adopted approach however, is off-pump CABG (OPCAB), in which CABG surgery is performed on one or more vessels through the usual median sternotomy approach without the aid of CPB. This article reviews the differences in the anesthetic considerations of OPCAB compared to conventional CABG using CPB.     

Coronary artery bypass grafting without cardiopulmonary bypass: MIDCAB and OPCAB

Minimally invasive direct coronary artery bypass grafting via left anterior small thoracotomy (MIDCAB) and coronary artery bypass grafting without cardiopulmonary bypass (OPCAGB) are accepted technique as less invasive than conventional coronary artery bypass grafting (CABG). We reported our experience with these procedures. From 1996 to December 1999, 176 patients underwent MIDCAB or OPCAB with the internal thoracic artery. The left internal thoracic arteries were used for grafting of the left anterior descending artery (LAD) in 131 patients, LAD and diagonal branches sequentially in 8 patients, using free radial artery conduits for grafting of the right coronary artery (RAC) or left circumflex (LCx) in 7 patients, using radial artery conduits as Y-graft from LAD for grafting of the RAC or LCx in 24 patients, and bilateral internal thoracic artery grafting was performed in 4 patients. One patient (0.6%) died in the hospital. One patient (0.6%) had perioperative myocardial infarction. No patient had cerebrovascular accident and sever wood infection. One-hundred-seventy-four patients (98.8%) had resolution of their angina symptom.     

Management of Traumatic Coronary Artery Injuries: Advantages of Off-Pump Coronary Artery Bypass

Coronary artery injuries are rare but highly lethal. Debate exists as to the best treatment for this complex set of injuries, with historical treatment favoring arterial ligation. Although conventional coronary artery bypass grafting using cardiopulmonary bypass has been used somewhat successfully, enthusiasm for off-pump CABG (OPCAB) has grown more recently. We report two unique cases of left anterior descending coronary arterial injuries managed successfully with OPCAB.     

MIDCAB for redo patients using the LITA-RA composite graft

Redo coronary artery bypass grafting (CABG) is associated with higher mortality, low-output syndrome, perioperative myocardial infarction than primary CABG. Minimally invasive direct coronary artery bypass grafting (MIDCAB) technique avoids the manipulation of old graft and injury of the adhesive heart in redo operation. We performed the MIDCAB procedure for 2 redo cases using the left internal thoracic artery (LITA)-radial artery (RA) composite graft. The LITA-RA composite graft was anastomosed to the left anterior descending branch (LAD) through small left anterior thoracotomy without cardiopulmonary bypass. Postoperative coronary artery graphy shows the widely patent of new graft. The MIDCAB procedure using the LITA-RA composite graft is safe and useful to regulate the bypass graft length and avoid the widely harvest of LITA in redo operation.     

心脏不停跳非体外循环冠状动脉旁路移植术的进展

近年来，随着手术器械的发展，心脏不停跳非体外循环下冠状动脉旁路移植术(OPCAB)逐渐被广泛接受和应用。与常规冠状动脉旁路移植术(CCABG)比较，OPCAB的主要优势为血液中多种炎性介质浓度明显降低，避免了体外循环(CPB)带来的全身系统性炎性损害，减少了并发症，降低了手术死亡率。特别对那些不能采用CPB或采用CPB有风险的高危患者优势更明显。CCABG的手术适应证同样适用于OPCAB，但OPCAB具有相对的禁忌证。OPCAB多采用胸骨正中切口，左前外侧切口适用于左前降支单支病变。OPCAB术后早期结果类似CCABG，但中远期结果有待进一步观察。OPCAB大多数旁路移植血管数低于CCABG，有不能完全再血管化的可能，对OPCAB是否会影响吻合的精确性和旁路血管的长期通畅率有不同意见。OPCAB的优势明确，但仍不能完全替代CCABG，手术的同时应作好CPB准备，必要时改行CCABG。     

Off-pump coronary artery bypass grafting: initial experience at one community hospital

BACKGROUND: This study reports one cardiac surgical center's experience with off-pump coronary artery bypass (OPCAB) and compares clinical risk factors and outcomes with a group of patients undergoing coronary artery bypass grafting (CABG) with cardiopulmonary bypass at the same institution. METHODS: Data on preoperative risk factors, intraoperative clinical markers, and postoperative outcomes were collected prospectively on all patients undergoing cardiac surgical procedures at our institution. From January 1, 1999, through October 7, 1999, 332 patients underwent OPCAB procedures at our institution. This group was compared with 445 consecutive patients undergoing CABG at the same institution during the period of January 1, 1998, through November 30, 1998. RESULTS: The two groups were similar with respect to preoperative clinical risk factors. Intraoperative data showed OPCAB patients tended to have fewer grafts performed and had a lower frequency of multiple grafts to obtuse marginal vessels. Outcomes showed no differences in the incidence of perioperative stroke, mediastinitis, reexploration for bleeding, pulmonary complications, new renal failure, postoperative atrial fibrillation, or transfusion of blood products. Patients in the OPCAB group had fewer perioperative myocardial infarctions and lower incidence of postoperative low cardiac output syndrome. A higher percentage of OPCAB patients had surgical lengths of stay of 5 days or less. The OPCAB group tended to have a lower in-hospital mortality rate but this difference did not reach statistical significance. CONCLUSIONS: Off-pump coronary artery bypass grafting with revascularization of all coronary artery segments is a safe and effective procedure that can be performed with equal or improved outcomes and shorter surgical lengths of stay compared with CABG with cardiopulmonary bypass.     

Clinical outcomes, angiographic patency, and resource utilization in 200 consecutive off-pump coronary bypass patients

BACKGROUND: This retrospective study compared clinical outcomes and resource utilization in patients having off-pump coronary artery bypass grafting (OPCAB) versus conventional coronary artery bypass grafting (CABG). Angiographic patency was documented in the OPCAB group. METHODS: From April 1997 through November 1999, OPCAB was performed in 200 consecutive patients, and the results were compared with those in a contemporaneous matched control group of 1,000 patients undergoing CABG. Patients were matched according to age, sex, preexisting disease (renal failure, diabetes, pulmonary disease, stroke, hypertension, peripheral vascular disease, previous myocardial infarction, and primary or redo status. Follow-up in the OPCAB patients was 93% and averaged 13.4 months. RESULTS: Hospital death (1.0%), postoperative stroke (1.5%), myocardial infarction (1.0%), and re-entry for bleeding (1.5%) occurred infrequently in the OPCAB group. There were reductions in the rates of transfusion (33.0% versus 70.0%; p < 0.001) and deep sternal wound infection (0% versus 2.2%; p = 0.067) in the OPCAB group compared with the CABG group. Angiographic assessment of 421 grafted arteries was performed in 167 OPCAB patients (83.5%) prior to hospital discharge. All but five were patent (98.8%) (93.3% FitzGibbon A, 5.5% FitzGibbon B, 1.2% FitzGibbon O). All 163 internal mammary artery grafts were patent. Off-pump coronary artery bypass grafting reduced postoperative hospital stay from 5.7 +/- 5.3 days in the CABG group to 3.9 +/- 2.6 days (p < 0.001), with a decrease in hospital cost of 15.0% (p < 0.001). CONCLUSIONS: Off-pump coronary artery bypass grafting reduces hospital cost, postoperative length of stay, and morbidity compared with CABG on cardiopulmonary bypass. Off-pump coronary bypass grafting is safe, cost effective, and associated with excellent graft patency and clinical outcomes.     

糖尿病病人行OPCAB与CCABG的早期结果对比

目的 比较糖尿病病人非体外循环和经典体外循环冠状动脉旁路移植(OPCAB和CCABG)的术后早期临床结果.方法 1999年4月至2008年1月,318例糖尿病病人行冠状动脉旁路移植术(CABG).OPCAB 210例,CCABG 108例.两组术前总体情况差异无统计学意义.OPCAB在非体外循环、心脏跳动下完成,CCABG在体外循环、心脏停跳下完成.正中开胸,胸膜外游离带蒂左乳内动脉(LIMA),与左前降支(LAD)吻合,大隐静脉(GSV)与其他靶血管吻合,吻合口超过2个采用序贯吻合.术前口服降糖药或皮下注射胰岛素将血糖控制在6 mmol/L以下,术后早期在ICU时持续泵入胰岛素,将血糖控制在6～8mmol/L.结果 两组共5例(1.57%)死亡,7例(2.20%)发生并发症.两组均达到完全再血管化,平均移植旁路血管OPCAB组(2.6±1.1)支,低于CCABG组的(3.1±1.3)支,P＜0.05.OWCAB组死亡1例(0.48%),明显低于CCABG组4例(3.70%),P＜0.05.OPCAB组发生并发症5例(2.30%),CCABG组2例(1.85%),组间差异无统计学意义,P＞0.05.结论 糖尿病者冠状动脉旁路移植手术围术期严格控制血糖至接近正常水平,住院病死率和并发症率低.OWAB术后早期病死率明显低于CCABG.     

Application of off-pump coronary artery bypass grafting for patients with acute coronary syndrome requiring emergency surgery.

Off-pump coronary artery bypass grafting (OPCAB) has become a more applicable procedure, even in patients with multi-vessel disease. However, the role of OPCAB for patients with acute coronary syndrome (ACS) requiring emergency revascularization has not been established yet. We reviewed our results of emergency coronary artery bypass grafting (CABG) for patients with ACS. Seventy-two patients with ACS who underwent emergency CABG were studied. Twenty-five underwent OPCAB and 47 on-pump CABG. OPCAB was mainly indicated for patients who were possibly at risk for cardiopulmonary bypass. When the coronary anatomy was suitable in younger or less risky patients, OPCAB was performed. Patients with multi-vessel disease or with a critical left main trunk lesion were not excluded from OPCAB. The mean number of grafted vessels was 2.6 per patient in the OPCAB group, and 3.8 per patient in the on-pump group (p<0.0001). However, none of the patients in either group required postoperative catheter intervention. Mean operative time was 195 minutes in the OPCAB group and 286 minutes in the on-pump group (p<0.0001). There were three postoperative deaths in the OPCAB group and four in the on-pump group. Multivariate logistic regression analysis revealed that preoperative cardiogenic shock was the only significant predictor for postoperative death (odds ratio, 7.33). The selection of the on-pump procedure or OPCAB did not correlate with operative death. Thus, we conclude that OPCAB can be performed safely and effectively in selected patients with ACS requiring emergency coronary revascularization.     

Stroke after conventional versus minimally invasive coronary artery bypass

BACKGROUND: Postoperative stroke is a serious complication after coronary artery bypass grafting with cardiopulmonary bypass (on-pump), and portends higher morbidity and mortality. It is unknown whether an off-pump cardiopulmonary bypass (OPCAB) approach may yield a lower stroke rate over conventional on-pump coronary artery bypass grafting. METHODS: From June 1994 to December 2000, OPCAB was performed in 2,320 patients and compared with 8,069 patients who had on-pump coronary artery bypass grafting, during the same period of time. The patients undergoing OPCAB were randomly matched to on-pump patients by propensity score. A logistic regression model was used to test the difference in the postoperative stroke rate between OPCAB and on-pump procedures controlling for the correlation between matched sets. A multiple logistic regression model predicting the risk of stroke adjusted by stroke risk factors and operation type was also computed. RESULTS: Matches by propensity score were found for 72% of the patients undergoing OPCAB. Patients undergoing on-pump coronary artery bypass grafting were 1.8 (95% confidence interval 1.0 to 3.1, p = 0.03) times more likely to suffer a stroke postoperatively than OPCAB patients after controlling for preoperative risk factors through matching. Independent predictors of stroke identified from the multiple logistic model included on-pump operation (versus OPCAB operation), female gender, 4 to 6 vessels grafted (versus <4 grafts), hypertension, history of previous cerebrovascular accident, carotid artery disease, chronic obstructive pulmonary disease, and depressed ejection fraction. CONCLUSIONS: Off-pump cardiopulmonary bypass avoids the risks of cardiopulmonary bypass and atrial trauma. A substantially lower stroke rate suggests that OPCAB is a neurologically safe treatment option for revascularization.     

Myocardial Revascularization of the Beating Heart in High-Risk Patients

OBJECTIVE: Myocardial revascularization without cardiopulmonary bypass (CPB) has been proposed as an alternative technique in patients at high risk for conventional coronary artery bypass grafting (CABG). The purpose of this article is to evaluate the potential benefit of such an approach. METHODS: We retrospectively evaluated the perioperative results of off-pump CABG (OPCAB) performed from January 1995 to December 1999. Patients were divided into three groups on the basis of their preoperative risk factors: age greater than 80 years, reoperative CABG, and left ventricular ejection fraction percentage (LVEF%) less than 40%. The three subgroups were compared with patients operated on-CPB (ONCAB) during the same period of time. A total of 172 octogenarians had ONCAB versus 97 OPCAB, 307 reoperations were ONCAB versus 274 OPCAB, and 514 patients with LVEF% less than 40% were operated ONCAB versus 220 OPCAB. RESULTS: Preoperative comorbidities were homogeneously distributed in the OPCAB and ONCAB groups. More extensive coronary artery disease was found in the ONCAB groups. A trend for a lower number of perioperative complications was reported in the OPCAB groups. Freedom from overall complications was significantly higher (p < 0.005) in the OPCAB group. Actual mortality rates in the OPCAB and ONCAB groups were comparable (p = NS). CONCLUSIONS: CABG can be performed safely without CPB in patients with a high preoperative risk profile. Freedom from perioperative complications is markedly higher when the OPCAB approach is utilized.     

Marsupialization of intramyocardial left anterior descending artery: a novel approach for easy access during revascularization

The left anterior descending (LAD) artery is the most important vessel bypassed during coronary revascularization procedures. This artery usually runs a superficial course, making it easy for localization and grafting. However, many times it takes a course deep in the myocardium or is embedded in thick epicardial fat, which results in technical challenges to the surgeon for localization and grafting. So far, many techniques are described for overcoming these problems, but all require cardiopulmonary bypass (CPB), and in fact, intramyocardial LAD is considered a relative contraindication for off-pump coronary artery bypass grafting (OPCAB). In the present era of enhanced interest in OPCAB, these techniques are not as helpful as they are for conventional CABG with CPB. Here, we describe a novel approach of marsupialization of the LAD for revascularization of intramyocardial LAD that is useful for off-pump as well as conventional revascularization procedures and makes grafting simple and reproducible.     

Coronary artery surgery results 2005 in Japan.

This report is focused on the status and outcome of coronary artery surgery performed in Japan, from January 1 to December 31, 2005. A total of 12,207 cases underwent coronary artery bypass grafting (CABG), as an isolated or concomitant procedure. Isolated CABG was performed in 9,827 patients. The operative mortality for patients who underwent isolated CABG was 1.91% in 2005. The mortality for initial elective CABG was 0.89%. These are the most improved results obtained since annual surveys started over 30 years ago. Since 1996 the number of off-pump CABG (OPCAB) cases increased year after year. This less-invasive procedure was performed on 4,936 patients in 2005, which is 61.0% the of total number of CABG cases. Mortality improved after complete OPCAB to 0.60%, which is the lowest rate since this procedure has been introduced. More than half (50.6%) of 4 and/or more grafting patients underwent OPCAB, which is higher rate than that (49.7%) in 2004. The percentage of elderly patients undergoing coronary artery bypass surgery is rising every year. In 2005, 46.5% of patients were aged 70 years or older and 7.8% were aged 80 years or older. The utilization rate of arterial grafts was 70%.     

Safe evolution towards routine off-pump coronary artery bypass: negotiating the learning curve

Objective: Off-pump coronary artery bypass (OPCAB) hopes to avoid morbidity associated with cardiopulmonary bypass, improving clinical outcomes. Yet its technical difficulty and unfamiliarity raise concern that adoption of OPCAB might be associated with poorer outcomes during each surgeon's ‘learning curve’. We examined trends in patient selection over time as a single surgeon's practice evolved to routine OPCAB. Methods: Between 10-1-96 and 12-31-01, 1479 consecutive patients had isolated coronary artery bypass grafting (CABG). Clinical data were gathered prospectively and reviewed retrospectively. Trends in adoption of OPCAB and clinical outcomes were examined. Results: There were 756 OPCAB and 723 CABG/cardiopulmonary bypass patients. The practice evolved from 90% conventional CABG to 93% OPCAB. An abrupt transition coincided with evolution of techniques to expose the obtuse marginal arteries, and improvements in suction-based coronary stabilizers. Mortality was 1.0% for the off-pump group and 2.1% for the on-pump group. Careful patient selection helped maintain acceptable outcomes during the ‘learning curve’. Patients with depressed left ventricular ejection fraction, left main disease, and complex three vessel disease were excluded from OPCAB until significant experience (>200 cases) was attained. Presently, all isolated coronary bypass cases are candidates for OPCAB except patients with ischemic ventricular arrhythmias, those in cardiac arrest, and those for whom previous left pneumonectomy or deep pectus excavatum prevent rightward mobilization of heart. Conclusions: Despite a significant learning curve, evolution to routine OPCAB can be achieved while maintaining good patient outcomes. The development of specialized techniques, coronary stabilizers, and apical suction devices allows the application of OPCAB to virtually all coronary bypass patients, as surgeon experience matures.     

Off-pump coronary artery bypass: techniques, pitfalls, and results

In coronary artery bypass grafting (CABG), coronary artery anastomosis is generally performed under cardiac arrest using cardiopulmonary bypass (CPB). To avoid the invasiveness of CPB, off-pump coronary artery bypass (OPCAB) is currently also used. In Japan, in particular, OPCAB now accounts for 60 % of all CABG operations and has become a standard surgical procedure. We herein provide a discussion of OPCAB. The goals of coronary artery bypass surgery are to achieve complete revascularization and maintain a high rate of graft patency for the long term. This requires stable exposure of the coronary arteries, including those located on the posterior surface of the heart and the formation of good-quality anastomoses. Achieving this depends not only on the competency of the individual surgeon, but also on smooth and effective teamwork among everyone involved, including the other surgeons, anesthetists, clinical technicians, and nurses. It is important for surgeons and surgical teams to examine their own outcomes and engage in self-scrutiny in an endeavor to improve these outcomes.     

Off-pump coronary artery bypass grafting/beating coronary artery bypass grafting for a patient with low left ventricular ejection fraction

Beating coronary artery bypass grafting could be performed for a 47-year-old man with left ventricular ejection fraction (LVEF) of 9.3%. Post-operative LVEF was improved to 51.6%. Conventional coronary artery bypass grafting (CABG) used to be contraindicative for patients with LVEF below 20%. Recently, such patients are involved to indication of off-pump CABG (OPCAB) or beating CABG, because we consider OPCAB are lower complications than conventional CABG. We were able to bypass the circumflex for the patient while we had been used percutaneous cardio-pulmonary support (PCPS). We could perform beating coronary artery bypass grafting for a patient of the low LVEF.     

Off-pump coronary artery bypass grafting: the Zurich experience

Coronary artery bypass grafting (CABG) is the surgical procedure of choice for treatment of multi-vessel coronary artery disease. The rising risk profile of the patients requiring isolated CABG and the economic pressure have prompted us to devise new operative strategies to treat these patients. Elimination of the cardiopulmonary bypass is one possible answer to the dilemma of maintaining the quality of care and reducing the exploding costs of our health system. Therefore, we developed the off-pump coronary artery bypass grafting (OPCAB) for patients requiring isolated CABG. In our experience the key to successful OPCAB relies on the order of revascularization of the myocardial walls (anterior, inferior, lateral), use of intracoronary shunt, no-touch technique for the proximal aortic anastomosis with heart string a (Guidant, IN, USA), close collaboration with the anesthesiologists, early and aggressive administration of anti-platelet therapy, endoscopic vein harvest by perfusionists, and improved body temperature control. Following these concepts, we have been able to offer the OPCAB procedure to over 90% of our patients and to reduce perioperative morbidity and global costs.     

On/off-pump beating coronary artery bypass grafting after thoracoplasty

Off-pump coronary artery bypass grafting (CABG) [OPCAB] or on-pump beating CABG (conventional CABG) was performed in 3 post-thoracoplasty patients. Considering their poor respiratory function after thoracoplasty, OPCAB is considered more suitable than conventional CABG with cardio-pulmonary bypass in such cases with severe coronary lesions. However, because the sternum inclines or the pleural cavity may be polluted in these patients, special care is necessary for the operation. In such cases, it may be impossible to bypass to the circumflex artery in OPCAB, and is necessary to consider the use of percutaneous cardiopulmonary support (PCPS), cardio-pulmonary bypass or hybrid therapy before the operation.