老年人非体外循环冠状动脉旁路移植术的心肌保护作用

目的比较70岁以上老年人非体外循环冠状动脉旁路移植术(OPCAB)和体外循环冠状动脉旁路移植术(CABG)围术期心肌损伤程度,探讨OPCAB的心肌保护效果。方法30例老年患者分为两组,A组15例,为CABG组,B组15例,为OPCAB组。分别于术前、术中30min、术中1h、术后6h、12h、24h、72h、120h取静脉血标本,分别测定心肌肌钙蛋白I(cTnI)水平和CKMB活性;另外记录围手术期各项临床指标。结果OPCAB组术后辅助呼吸时间较CABG组短(P<0.01),而且主动脉球囊反搏和输血例数较低(P<0.05)。CABG组与OPCAB组cTnI、CKMB的术前水平相,术后6hcTnI即有升高而后下降,术后30min至72h均较OPCAB组明显升高(P<0.05或0.01)。结论与CABG相比,OPCAB的心肌损伤较轻,心肌保护效果较好。     

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.     

Off‐pump,minimally invasive and robotic coronary revascularization yield improved outcomes over traditional on‐pump CABG

Coronary artery disease is a global health concern, with increasing morbidity and mortality. Surgical coronary artery bypass grafting has been performed on cardiopulmonary bypass for nearly four decades, with excellent long‐term durability. Beating‐heart coronary surgery has been increasing in frequency in an attempt to decrease cardiopulmonary bypass‐related morbidity. Furthermore, with increasing expertise and technology, minimally invasive and robotic techniques have been developed to enhance post‐operative recovery, patient satisfaction and cosmesis. Several clinical trials have demonstrated decreased morbidity and more rapid recovery following off‐pump, minimally invasive and robotic procedures when compared to on‐pump coronary artery bypass grafts (CABGs). An equivalent extent of revascularization and medium‐term anastomotic patency has been demonstrated among all approaches. Furthermore, for a large number of patients who do not have anatomy amenable to traditional coronary revascularization, adjunctive molecular therapies may provide alternative myocardial micro‐revascularization. Copyright © 2008 John Wiley & Sons, Ltd.     

Conversion to Cardiopulmonary Bypass in Off-pump Coronary Artery Bypass Grafting: Its Effect on Outcome

The surgical outcome of patients requiring conversion to cardiopulmonary bypass (CPB) during myocardial revascularization using the less invasive surgical approach (LISA) was assessed. The LISA was recently introduced as a technique for complete myocardial revascularization without CPB. It combines avoidance of CPB with the versatility of a median sternotomy for access to all coronary vessels. We have previously demonstrated reduced risk-adjusted mortality and complications in off-CPB coronary artery bypass grafting (CABG) using LISA compared to standard myocardial revascularization. From January to December 1997, 1210 patients underwent isolated CABG at our institution. Of these patients, 832 (63%) were scheduled as on-CPB cases and 378 (37%) as off-CPB. Of the off-CPB patients, 48 were converted to CPB. Team A surgeons used LISA as their primary strategy for CABG whereas team B surgeons used off-CPB CABG in selected patients. Conversions were divided in three classes: Class I patients were converted when the surgeon considered complete revascularization impossible off-CPB; Class II patients were converted due to hemodynamic instability during the procedure; and Class III patients were converted due to graft malfunction, determined by flow measurements or clinical evidence. There were four deaths. All had perioperative infarctions and required intra-aortic balloon pump (IABP). Conversion to CPB occurred in up to 25% of patients scheduled for off-CPB CABG. When off-CPB cases are done using the comprehensive LISA technique and modern technology, conversion rates may be reduced to 11%. Conversion is in general well tolerated except when it is instituted for graft malfunction combined with hemodynamic instability or collapse.     

Off-pump technique in coronary artery bypass grafting in elderly patients

Background: The use of cardiopulmonary bypass (CPB) during coronary artery bypass grafting (CABG) is associated with substantial morbidity and mortality, especially in the elderly. The purpose of this study was to evaluate the feasibility of beating heart coronary artery revascularization in patients aged at least 80 years. Methods: A retrospective chart review was carried out for 17 patients aged over 80 years who underwent isolated off‐pump CABG at the Tri‐Service General Hospital, Taiwan, during the period July 1999 to December 2000. The demographic characteristics, operative data, postoperative results and short‐term outcomes of patients were compared with those of 12 patients who underwent conventional CABG using CPB during the same time period. Results: The off‐pump group consisted of 13 men and four women with a mean age of 82.2 ± 0.9 years and an ejection fraction of 53.4 ± 4.1%. The on‐pump group consisted of eight men and four women with a mean age of 83.5 ± 0.5 and an ejection fraction of 42.0 ± 4.8%. The mean number of anastomoses performed per patient was 3.1 ± 0.3 in the off‐pump group and 3.0 ± 0.14 in the on‐pump group. There was no occurrence of stroke, myocardial infarction, re‐entry for bleeding or renal failure among patients in the off‐pump group. Intubation time (10.6 vs 48.4 h), intensive care unit stay (2.9 vs 4.2 days) and postoperative stay (12.7 vs 18.1 days) were significantly shorter in the off‐pump group than in the on‐pump group. No patient died in the off‐pump group, whereas one patient died in the on‐pump group. Conclusions: The results of this study suggest that the off‐pump technique is a safe and efficacious method for myocardial revascularization in elderly patients and that the short‐term outcome obtained with this technique are promising. Our data suggest that the off‐pump technique is preferable in these patients.     

Myocardial revascularization without extracorporeal circulation

Contemporary treatment of coronary disease includes: drug treatment, percutaneous coronary angioplasty (PCI), with or without stent implantation and surgical myocardial revascularization. For more than 30 years, conventional coronary bypass (on-pump CABG), using cardiopulmonary bypass (CPB), represented the standard regarding myocardial revascularization, particularly in patients suffering from three vessel disease or left main coronary artery stenosis. Recent development of invasive cardiology and increased interest in coronary surgery on the beating heart (OPCAB), challenging traditional on-pump CABG procedure, as optimal strategy for the treatment of coronary artery disease. In order to improve clinical outcome, OPCAB seems to be a good choice in patients with co-morbidities critical for use of CPB. Results of OPCAB revascularization in general patient population are considerably different and require further evaluation. This review article shows the development of OPCAB and elaborates potential advantages and weaknesses of this method of revascularization, from both, theoretical and clinical point of view, compared to standard surgical myocardial revascularization.     

Beating versus arrested heart revascularization: evaluation of myocardial function in a prospective randomized study.

OBJECTIVE: Conventional coronary artery bypass grafting (CABG) is both safe and effective. Nevertheless, the use of cardiopulmonary bypass (CPB) and cardioplegic arrest are associated with several adverse effects. Over the last 2 years there has been a revival of interest in performing CABG on the beating heart. In this prospective randomized study we evaluated the efficacy and safety of on and off pump coronary revascularization on myocardial function. METHODS: Eighty patients (65 males, mean age 61+/-9.7 years) undergoing first time CABG were prospectively randomized to: (i) conventional revascularization with CPB at normothermia and cardioplegic arrest with intermittent warm blood cardioplegia (on pump) or (ii) beating heart revascularization (off pump). Troponin I (Tn I) release was serially measured as a specific marker of myocardial damage. Haemodynamic measurements as well as inotropic requirement, incidence of arrhythmia and postoperative myocardial infarction were also recorded. RESULTS: There were no significant differences between the two groups in terms of age, sex, extent of disease, left ventricular function and number of grafts. There were no deaths or intraoperative myocardial infarctions in either group. Tn I release was constantly lower in the off pump group and this was significant at 1, 4, 12 and 24 h postoperatively. Furthermore, in this group there was a significantly reduced incidence of arrhythmias. Inotropic requirements were less in the off pump group but this did not reach statistical significance. CONCLUSION: These results suggest that off pump coronary revascularization is a safe and effective strategy for myocardial revascularization. Myocardial injury as assessed by Tn I release is also reduced when compared with conventional coronary revascularization with CPB and cardioplegic arrest.     

Initial experience with beating heart surgery: comparison with fast-track methods.

Cardiopulmonary bypass (CPB) in coronary artery bypass grafting (CABG) may increase postoperative complications in high-risk patients. The goal of this study is to retrospectively review a series of consecutive patients undergoing conventional CABG using a fast-track recovery method and to compare this series with the initial series of patients undergoing beating heart surgery using either the single-vessel minimally invasive approach or the off-pump multivessel bypass technique with a median sternotomy. One hundred fifty-eight consecutive patients underwent CABG. One hundred four patients underwent conventional CABG using CPB with a short-pump fast-track recovery method (Group A). Twenty-nine patients underwent a single-vessel bypass via a left anterior thoracotomy off pump [Group B, minimally invasive direct coronary artery bypass (MIDCAB)]. Twenty-five patients underwent multivessel CABG with a median sternotomy off pump (Group C). Short-pump fast-track (Group A) patients exhibited minimal complications and expedient recovery and received extensive revascularization. Off-pump multivessel patients (Group C) received fewer bypass grafts, had more preoperative comorbidity, and recovered as quickly as lower-risk fast-track short-pump patients (Group A). Single-vessel off-pump patients (Group B, MIDCAB) were younger elective patients and demonstrated no recovery advantage. The overall mortality was 1.8 per cent. The conversion rates from beating heart surgery to CPB for groups B and C were 10.3 and 16 per cent, respectively. The postoperative hospital length of stay for groups A, B, and C were 4.8+/-2.4, 3.9+/-1.8, and 5.2+/-2.3 days, respectively. Eliminating CPB is not as important as reducing exposure for minimizing operative risk. Beating heart surgery is an adjunct to conventional CABG with CPB. The off-pump multivessel bypass technique is best suited for high-risk patients requiring three grafts or fewer, whereas MIDCAB is best suited for single-vessel bypass that cannot be managed using interventional percutaneous techniques; however, the recovery advantage with MIDCAB is not apparent. Patients requiring more than three bypass grafts should undergo conventional CABG with CPB.     

A Prospective Observational Study to Compare Conventional Coronary Artery Bypass Grafting Surgery with Off‐Pump Coronary Artery Bypass Grafting on Basis of EuroSCORE

Abstract Introduction: The use of cardiopulmonary bypass during coronary artery bypass grafting (CABG) surgery has been associated with substantial morbidity. Off‐pump coronary bypass (OPCAB) surgery has become a widely used technique during recent years. EuroSCORE risk scale is the most rigorously evaluated scoring system in cardiac surgery to preoperatively quantify the risk of death and other serious postoperative complications. The aim of this prospective observational study was to compare the mortality and morbidity between OPCAB and conventional CABG in three major preoperative groups as assessed by EuroSCORE. Material and Method: All consecutive patients undergoing isolated coronary artery bypass surgery between January 2003 and December 2004 at Wellington Hospital were included. In this period, 347 patients had conventional CABG and 254 patients had OPCAB. Data were prospectively collected according to Australasian Society of Cardiothoracic Surgeons’ cardiac surgery data set. The preoperative additive EuroSCORE was computed in each patient and the patients were divided into three risk groups. Results of OPCAB and conventional CABG were compared on basis of EuroSCORE group. Results: OPCAB surgery is preferably performed in patients with low‐risk. OPCAB group had lesser number of grafts per patient. When adjusted with risk score, there was no statistically significant difference in mortality in any of the three groups. No significant difference was found for stroke, renal dysfunction, atrial fibrillation, re‐exploration for bleeding, deep sternal wound infection, or pulmonary complications in either of three groups. However, inotropic requirement and requirements of blood products were less in OPCAB group. Conclusion: OPCAB does not offer any significant advantage in terms of mortality and morbidity over conventional CABG. (J Card Surg 2010;25:495‐500)     

Beating heart coronary artery bypass grafting

Objectives: We have studied the results of 402 consecutive cases of beating heart coronary artery bypass grafting (CABG) and evaluated the usefulness of gastroepiploic artery (GEA) composite grafts. Methods: Between March 1993 and August 2001, 402 patients underwent beating heart CABG. They were 321 male and 81 female patients, aged 17 to 88 (mean 66) years. Beating heart CABG was facilitated by mechanical stabilization with a doughnut stabilizer, a newly designed sternal retractor and a new coronary perfusion system. Minimally invasive direct coronary artery bypass (MIDCAB) was performed in 206 patients (the MIDCAB Group), and beating heart CABG with median sternotomy (OPCAB) was performed in 196 patients (the OPCAB Group). Results: Definite off-pump CABG was accomplished in 381 patients. 21 patients (5%) were converted to on-pump beating heart CABG using percutaneous cardiopulmonary system via femoral vessels because of hemodynamic instability. There was 1 operative mortality (0.2%). There was perioperative myocardial infarction in 2 (0.5%), and cerebral infarction in 3 (0.7%). The rate of complete revascularization was 78% in the MIDCAB Group and 97% in the OPCAB Group. The mean number of anastomoses was 1.6 in the MIDCAB Group and 3.3 in the OPCAB Group. The early graft patency was 99.1% in a left internal thoracic artery graft, 97.0% in a right internal thoracic artery graft, 96.5% in GEA, 98.2% in a radial artery graft, and 94.2% in a vein graft. A GEA composite graft was used in 55 of the 168 patients who received GEA grafting. The mean number of anastomoses for the GEA composite graft was 1.6±0.6 per patient. The graft patency rate was 94.6% (53/56) for GEA and 98.6% (72/73) for the radial artery used as a composite graft. Conclusion: A consecutive series of beating heart CABG was performed safely and effectively with a low mortality rate and low morbidity rate. Beating heart CABG could be performed in all patients, and definite off-pump CABG was accomplished in 95% of them. In order to aim for complete revascularization, GEA composite graft was found to be effective since it required a low mean number of 1.6 anastomoses and a satisfactory patency rate at the same time. Read at the Fifty-fourth Annual-Meeting of the Japanese Association for Thoracic Surgery, Panel discussion, Osaka, October 3–5, 2001.     

Minimally Circulatory‐Assisted On‐Pump Beating Coronary Artery Bypass Grafting for Patients With Complex Conditions for Off‐Pump Surgery

Off‐pump coronary artery bypass grafting (OPCAB) in patients with acute myocardial infarction (AMI) is difficult because of circulatory deterioration during displacement of the heart. At our institution, we performed minimally circulatory‐assisted on‐pump beating coronary artery bypass grafting (MICAB) in these patients. During MICAB, support flow was controlled at a minimal level to maintain a systemic blood pressure of approximately 100 mm Hg and a pulmonary arterial systolic pressure of <30 mm Hg, providing optimal pulsatile circulation for end‐organ perfusion and prevention of heart congestion. From September 2006 to March 2012, MICAB was performed in 37 patients. Either emergent or urgent MICAB was performed in 27 patients following AMI because of hemodynamic instability during reconstruction. Elective MICAB was performed in the remaining 10 patients because of dilated left ventricle (LV) or small target coronary arteries. The details of bypass grafts, perioperative renal function, and early and mid‐term morbidity and mortality were compared between the patients who received MICAB and the 37 consecutive patients who underwent OPCAB during the study period at our hospital. The assist flow indices (actual support flow/body surface area) during anastomosis to the left anterior descending artery, left circumflex artery, and right coronary artery were 0.95 ± 0.48 L/min/m², 1.32 ± 0.53 L/min/m², and 1.15 ± 0.47 L/min/m², respectively, in the emergent and urgent patients following AMI, and 0.44 ± 0.39 L/min/m², 1.25 ± 0.39 L/min/m², and 1.14 ± 0.43 L/min/m², respectively, in the elective patients with either dilated LVs or small target vessels. The lowest mixed venous oxygen saturation during pump support in the MICAB group was significantly higher than that in the OPCAB group (83.8 ± 10.8%, 71.6 ± 7.5%, P < 0.001). Comparing MICAB and OPCAB, the median number of distal bypass grafts for both groups was 4 (25th, 75th percentile: 3, 4) (P = 0.558); the complete revascularization rates were 94.6 and 97.3%, respectively (not significant [NS]); the acute patency rates were 98.9 and 99.2%, respectively (NS); and the 30‐day mortality rates were 2.7 and 0%, respectively (NS). No instances of either cerebrovascular complications or newly occurring postoperative renal failure were noted in either group. There were no statistically significant differences between the groups with respect to early and mid‐term results (freedom from all‐cause death: 82.9 vs. 86.5%, respectively, and freedom from cardiac events at 3 years: 96.4 vs. 96.4%, respectively). MICAB is a safe alternative to OPCAB, particularly in patients with AMI and dilated LV. MICAB is associated with high rates of complete revascularization and acute graft patency, adequate preservation of end‐organ function, and early and mid‐term results comparable with those observed following OPCAB.     

‘No Touch’ Techniques for Porcelain Ascending Aorta: Comparison Between Cardiopulmonary Bypass with Femoral Artery Cannulation and Off‐Pump Myocardial Revascularization

Abstract Background: Detection of severe atherosclerotic ascending aorta during coronary artery bypass grafting requires alterations in the standard surgical technique to reduce the probability of stroke‐related atheroembolization. Off‐pump coronary artery bypass grafting (OPCAB) confers the benefits of avoiding aortic cannulation and clamping, and may therefore attenuate this risk. Methods: OPCAB (n # 41) was compared to cardiopulmonary bypass (CPB) using femoral arterial cannulation and hypothermic fibrillatory arrest (n = 15), in patients with porcelain ascending aorta undergoing myocardial revascularization. In both groups, a ‘no touchrsquo; technique was applied by avoiding aortic cannulation and clamping. Proximal anastomoses on the atherosclerotic aorta were avoided by arterial grafting, (in‐situ or T‐graft configurations) in all cases. Results: Operative mortality was comparable (2.4% and 6.6% in the OPCAB and CPB groups respectively, p # NS). The rate of adverse neurological events, (two strokes and one transient ischemic attack), was higher in the CPB group (p # 0.0164). Based on brain CT, the nature of the recorded stroke suggested retrograde emboli. Three year survival (Kaplan‐Meier) for the OPCAB and CPB groups was 86.7% and 81.3%, respectively (p = NS). Occurrence of late neurological adverse events during follow‐up (8–51 months) was similar. Conclusions: In patients with porcelain ascending aorta undergoing myocardial revascularization, neurological outcome of OPCAB patients is better than CPB using femoral artery cannulation.     

Off pump coronary artery bypass (OPCAB) in critical left mainstem stenosis—Our experience

Background Beating heart surgery has now become the commonest technique of doing Coronary Artery Bypass Graft Surgery (CABG) in our country. It is being used even in such high risk situations like diffuse coronary disease and Critical Left Main stem Stenosis (LMCS) with good results. The aim of this study is to retrospectively review our results in Off-Pump Coronary Artery Bypass Surgery (OPCAB) in patients with critical left main stem stenosis. Methods This study is a retrospective analysis of the data of patients who underwent primary coronary artery bypass surgery. During the period from April 2003 to September 2005 a total of 64 patients underwent OPCAB procedure for critical LMCS. During the same period 10 patients underwent CABG on Cardio Pulmonary Bypass (CPB). The age range was 36–77yrs. The sex distribution was M: F 53∶10. Ten patients were done as emergency. 2 of them were on Intra Aortic Balloon Pump (IABP) support preoperatively. 10 patients were high risk with a Euro score of ≥5. Results Left Internal Mammary Artery (LIMA) was used in 78% of cases. Average grafts per patient was 2.96. The median ventilation time was 5.91 hrs. New IABP insertion in postoperative period was required in 1 patient. One patient was reexplored for bleeding. There was one perioperative myocardial infarction. 57% of patients did not need any blood transfusion. There was no conversion to CPB. There was no operative mortality. Inotropes were used in ten cases. Conclusions OPCAB is a safe method of revascularization in patients with critical LMCS. Preoperative IABP is useful in patients with cardiogenic shock. However, there is a place for CPB in patients needing additional procedures like Mitral Valve repair (MV repair) or Dor's procedure or when the vessels are very diffusely diseased. Those patients who are unstable despite IABP support may be managed by Beating heart On Pump (BHOP) technique.     

Quantification of fat mobilization in patients undergoing coronary artery revascularization using off-pump and on-pump techniques

Fat mobilization during cardiopulmonary bypass (CPB) is a recognized risk of the procedure. Intravascular mobilization of fat emboli subsequent to CPB has been implicated in some of its recognized pathophysiologies, particularly with regard to cerebral embolic injury. The aim of this study was to investigate whether fat mobilization is still a real issue in modern perfusion practice and to determine whether off pump coronary artery bypass techniques minimize this risk. Thirty patients undergoing routine elective coronary artery bypass graft (CABG) surgery were divided into two groups. Group 1 patients underwent off pump coronary artery bypass (OPCAB) procedures, and group 2 underwent CABG supported with CPB. Blood samples were taken from the CPB patients at the beginning, middle, and end of the procedure, from the suction line, from the arterial line, and from the venous line for measurement of fat emboli present. Samples were taken at corresponding time-points from the OPCAB patients for similar measurements. Fat emboli were counted manually using Oil red O staining and light microscopy. The fat emboli were sized using calibrated microspheres as a visual size contrast. No fat emboli were observed in any of the blood samples taken from the OPCAB patients. There were fat emboli present in all samples taken during CPB from all sources. The count was highest in the suction system and lowest in the venous blood and tended to increase during CPB. There was an absence of large fat emboli in the venous blood, which tends to indicate that the larger fat emboli lodge in the microvasculature. OPCAB surgery eliminates the risk of fat embolization in patients undergoing coronary revascularization. The suction system is the major source of fat emboli during CPB, and despite the multiple filtration components of the CPB system, fat emboli of various and significant sizes do reach the patient. Fat embolization remains a risk in routine elective CABG surgery. Cardiotomy suction should be eliminated where possible.     

Midterm outcomes of off-pump and on-pump coronary artery revascularization in renal transplant recipients

Abstract Objectives: Renal transplant recipients have high mortality from cardiac causes and are frequently in need of coronary interventions. Surgical coronary revascularization is associated with significant morbidity and mortality in this patient population. This study was undertaken to evaluate outcomes of on‐pump versus off‐pump revascularization in renal transplant recipients. Methods: We retrospectively reviewed 43 renal transplant recipients who underwent surgical coronary revascularization with functioning allografts. Revascularization was performed on‐pump [coronary artery bypass grafting (CABG)] in 21 patients and off‐pump [off‐pump coronary artery bypass (OPCAB)] in 22 patients. Results: Preoperative characteristics did not differ between the two groups except for age and incidence of prior sternotomy. Total operative time and transfusion requirements were similar. The on‐pump group received a higher number of bypass grafts (p = 0.03). Overall 30‐day, one‐year, five‐year, and eight‐year survival was 90%, 76%, 61%, and 32% for CABG group, and 95%, 86%, 62%, and 48% for OPCAB group (p = 0.53). The postoperative peak creatinine was higher in the CABG patients than in OPCAB patients (p = 0.04). At discharge, there was no difference in mean creatinine between the two groups. The rate of return to permanent dialysis after revascularization was similar (28% for CABG and 22% for OPCAB, p = 0.73). There was no difference in dialysis‐free survival up to eight‐years postrevascularization (p = 0.63). Conclusions: Despite higher mortality risk, surgical coronary revascularization can be performed safely in renal transplant recipients. OPCAB resulted in no improvement in patient survival or renal allograft function compared to on‐pump revascularization. (J Card Surg 2011;26:591‐595)     

On-pump versus off-pump coronary revascularization: evaluation of renal function.

BACKGROUND: Coronary revascularization with cardiopulmonary bypass has the potential risk of renal dysfunction related to the nonphysiologic nature of cardiopulmonary bypass. Recently, there has been a revival of interest in performing myocardial revascularization on the beating heart and we investigated whether this prevents renal compromise. METHODS: A prospective, randomized, controlled trial was performed in 50 patients (45 males, mean age 61+/-3.7 years) undergoing elective coronary artery bypass grafting. Patients were randomly assigned to conventional revascularization with cardiopulmonary bypass (on pump) or beating heart revascularization (off pump). Glomerular and tubular function were assessed up to 48 hours postoperatively. RESULTS: There were no deaths, myocardial infarctions or acute renal failure in either group. Glomerular filtration as assessed by creatinine clearance and the urinary microalbumin/creatinine ratio was significantly worse in the on pump group (p < 0.0004 and 0.0083, respectively). Renal tubular function was also impaired in the on pump group as assessed by increased N-acetyl glucosaminidase activity (p < 0.0272). CONCLUSIONS: These results suggest that off pump coronary revascularization offers a superior renal protection when compared with conventional coronary revascularization with cardiopulmonary bypass and cardioplegic arrest in first time coronary bypass patients.     

Beating heart coronary artery bypass grafting for acute myocardial infarction

We consider that off-pump coronary artery bypass grafting (CABG) [OPCAB], which results in local myocardial ischemia, is more effective for patients with acute myocardial infarction (AMI) than conventional CABG under cardiac arrest with global myocardial ischemia. Twenty-one patients (15 males, 6 females) received OPCAB for AMI, among whom surgery was performed following percutaneous coronary intervention (PCI) failure in 4 and PCI was performed prior to OPCAB in 2, while PCI was not performed in the remaining 15. Preoperatively, 16 patients had intraaortic balloon pumping (IABP), and 4 had IABP and percutaneous cardiopulmonary support (PCPS). The mean interval from onset to surgery was 11.7 (range 3 to 40) hours. In 20 cases, a complete revascularization was performed. The mean number of bypasses was 2.3 and OPCAB was carried out in 14 patients. In 2 cases, OPCAB was converted to on-pump beating CABG for complete revascularization. Fourteen patients (67%), each maintained with preoperative left ventricular ejection fraction (EF), were discharged with an elective bypass. Four patients died after on-pump beating CABG, in whom EF was lower than 10%. In addition, 3 died of low cardiac output syndrome (LOS) under PCPS and 1 of ventricular fibrillation. Based on our results, we considered that complete revascularization using OPCAB was effective for cases of AMI with PCI difficulty. However, in shock cases requiring PCPS, cardiac function was not improved even after revascularization. Therefore, it is necessary to study new procedures for shock cases during the period from onset to surgery.     

Inflammatory response after coronary revascularization with or without cardiopulmonary bypass

BACKGROUND: We sought to investigate the effect of multiple coronary artery bypass grafting (CABG) with or without cardiopulmonary bypass (CPB) on the perioperative inflammatory response. METHODS: Sixty patients undergoing CABG were randomly assigned to one of two groups: (A) on pump with conventional CPB and cardioplegic arrest, and (B) off pump on the beating heart. Serum samples were collected for estimation of neutrophil elastase, interleukin 8 (IL-8), C3a, and C5a preoperatively and at 1, 4, 12, and 24 hours postoperatively. Furthermore, white blood cell (WBC), neutrophil, and monocyte counts were carried out preoperatively and at 1, 12, 36 and 60 hours postoperatively. Overall incidence of infection and perioperative clinical outcome were also recorded. RESULTS: The groups were similar in terms of age, weight, gender ratio, extent of coronary disease, left ventricular function, and number of grafts per patient. Neutrophil elastase concentration peaked early after CPB in the on-pump group, with a decline with time. Repeated-measures analysis of variance between groups and comparisons at each time point (modified Bonferroni) showed elastase concentrations were significantly higher in the on-pump than the off-pump group (both p < 0.0001). IL-8 increased significantly after surgery in the on-pump group, with no decline during the observation period (p = 0.01 vs off pump). C3a and C5a rose early after surgery in both groups when compared with baseline values. Postoperative WBC, neutrophil, and monocyte counts were significantly higher in the on-pump than the off-pump group (p < 0.01). Finally, the incidence of postoperative overall infections was significantly higher in the on-pump group (p < 0.0001 vs off pump). CONCLUSIONS: CABG on the beating heart is associated with a significant reduction in inflammatory response and postoperative infection when compared with conventional revascularization with CPB and cardioplegic arrest.     

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.     

Hemoglobin Trends in Isolated Coronary Artery Bypass Grafting Performed Off‐Pump and With Standard and Mini Circuits

The comparison of hemodilution at the end of surgery is of limited use as it represents only a snapshot of a dynamic phenomenon. This study was undertaken to compare the perioperative hemoglobin curves of isolated coronary artery bypass grafting performed with minimized extracorporeal circulation, traditional cardiopulmonary bypass, and off‐pump technique. The propensity score method was used to select three groups of patients, homogenous regarding preoperative and operative data, who underwent isolated coronary artery bypass grafting. A generalized linear mixed model was used for estimating differences in perioperative hemoglobin trends among groups. The three groups were each composed of 50 patients with no differences in demographic data, preoperative risk profile, preoperative hemoglobin, or type of surgery. There was no significant difference in major postoperative complications. The pattern of the hemodilution curves was similar in patients operated with mini‐circuit and off‐pump technique (P > 005). Mini‐circuit led to a 3.1 ± 11.9% hemoglobin reduction, which was similar to the off‐pump group (1.6 ± 8.9%, P = 0.99 at ANOVA) and significantly different from the standard extracorporeal circuit group (16.0 ± 10.3%, P < 0.001 at ANOVA). The generalized linear mixed model determined that the standard circuit was the only independent predictor for increased hemodilution. Its effect on hemodilution was time‐dependent and the slope of the hemoglobin curve was more pronounced between systemic heparinization and the end of surgery. Perioperative hemoglobin trends of patients who underwent myocardial revascularization with mini‐circuit were similar to those of off‐pump surgery and significantly less pronounced than those of standard extracorporeal circulation.