Intraoperative color Doppler ultrasound assessment of LIMA-to-LAD anastomoses in off-pump coronary artery bypass grafting

BACKGROUND: Although techniques for off-pump coronary artery bypass grafting (CABG) are continually being refined, angiographic follow-up studies have indicated a higher rate of anastomoses-related stenoses than expected after traditional on-pump CABG. This study was performed to evaluate the use of intraoperative epicardial color Doppler ultrasound to quality-assess left internal mammary artery (LIMA) to left anterior descending coronary artery (LAD) anastomoses performed on the beating heart. METHODS: Twenty-four LIMA-to-LAD anastomoses were evaluated with real-time epicardial ultrasound imaging using an ultrasound transducer positioned between the paddles of the stabilizer during off-pump procedures. The length of the anastomosis (D(A)), diameters of LIMA (D(M)), LAD at the toe of the anastomosis (D1), and 5 mm distally to the anastomosis (D2) were measured, and the ratios between these variables were calculated. The flow velocity through the anastomoses was visualized by color Doppler coding, and flow was assessed with transit-time flowmetry. RESULTS: The epicardial color Doppler ultrasound allowed accurate assessment of the anastomoses. Twenty-three (96%) of the primary anastomoses were confirmed as patent. Mean ratios of D1/D2, D(A)/D2, and D(M)/D2 were 0.89 +/- 0.13, 3.01 +/- 1.04 and 1.32 +/- 0.32, respectively. One anastomosis had a stenosis more than 50% detected by color Doppler ultrasound. After surgical revision, transit-time flow increased from 22 to 40 ml/min. CONCLUSIONS: Intraoperative color Doppler ultrasound allowed adequate imaging for quality assessment of LIMA-to-LAD anastomoses performed on the beating heart. One anastomosis was revised due to a technical error detected by epicardial color Doppler imaging. Epicardial ultrasound scanning is a valuable tool for intraoperative assessment of LIMA-to-LAD anastomoses during off-pump coronary surgery.     

Beating heart versus conventional single-vessel reoperative coronary artery bypass

BACKGROUND: Reoperative (redo) coronary artery bypass grafting (CABG) with cardiopulmonary bypass (on-pump) is associated with a higher morbidity and mortality than first-time CABG. It is unknown, however, whether CABG without cardiopulmonary bypass (off-pump) may yield an improved clinical outcome over conventional on-pump redo CABG. METHODS: We compared the perioperative outcomes of patients with single-vessel disease who underwent on-pump (n = 41) versus off-pump (n = 91) redo CABG between April 1992 and July 1999. The two groups were similar with respect to baseline characteristics and risk stratification: mean Parsonnet scores were 26 +/- 9 for on-pump versus 24 +/- 8 for off-pump patients (p = nonsignificant). RESULTS: On-pump redo patients had a higher rate of postoperative transfusions (58% on-pump versus 27% off-pump, p = 0.001), prolonged ventilatory support (17% on-pump versus 4% off-pump, p = 0.03), and a higher rate of postoperative atrial fibrillation (29% on-pump versus 14% off-pump, p = 0.04). On-pump redo CABG was also associated with prolonged postoperative length of stay (8 +/- 4 days on-pump versus 5 +/- 2 days off-pump, p < 0.001). In-hospital mortality was significantly higher in on-pump than in off-pump patients (10% versus 1%, p = 0.03). CONCLUSIONS: Single-vessel off-pump redo CABG can be performed safely with a lower operative morbidity and mortality than on-pump CABG and an abbreviated hospital stay compared with conventional on-pump redo CABG.     

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.     

非体外循环和体外循环冠状动脉旁路移植术在二次冠状动脉旁路移植术中的应用

目的研究对比在二次冠状动脉旁路移植术(re-CABG)患者中分别采用非体外循环和体外循环下冠状动脉旁路移植术(off-pump CABG和on-pump CABG)的临床早期结果,探讨通过合理手术方式的选择,提高re-CABG的手术疗效。方法自2000年4月到2006年6月,21例首次CABG后因心绞痛复发患者在阜外心血管病医院接受了re-CABG手术,其中10例行off-pump CABG(off-pump组),11例行on-pump CABG(on-pump组)。两组患者术前性别、年龄、体重、心肺功能、心绞痛程度、左心室舒张期末内径、射血分数、合并高血压、糖尿病等方面差异无统计学意义(P>0.05)。结果 On-pump组中患者术后死亡1例,冠状动脉远端吻合口数多于off-pump组(P<0.05);off-pump组无手术死亡,在手术时间、术后呼吸机辅助时间、胸腔引流液量、输血量和手术后住院时间等方面,均明显少于on-pump组(P<0.05)。结论 Off-pump CABG和on-pump CABG技术在re-CABG中都可以取得满意疗效,off-pump CABG下施行re-CABG安全可靠。     

Multivessel distal sutureless off-pump coronary artery bypass grafting procedure using magnetic connectors

Proximal anastomotic devices for beating heart coronary artery bypass grafting (CABG) have been developed to avoid ascending aortic manipulation. Distal anastomotic devices may become an extremely useful tool to assist in enabling minimally invasive (robotic) multivessel CABG. As a transition phase toward this ultimate goal we have been using a distal anastomotic device for the left internal mammary artery-left anterior descending artery (LIMA-LAD) anastomosis. In addition we recently performed two off-pump coronary artery bypass procedures that were distally completely sutureless.     

瞬时流量测定技术在冠状动脉旁路移植术中的应用及其相关因素分析

目的 评估瞬时流量测定（transit time flow meter，TTFM）技术在冠状动脉旁路移植术（CABG）中探查移植血管血流通畅状态的应用价值，并分析其测定结果的相关因素。方法 对我科2002年3月至2004年1月连续行CABG301例患者的791支血管移植物进行TTFM测定，按照入选标准从中筛选出左乳内动脉（LIMA）旁路移植到左前降支（LAD）的165例患者的TTFM结果，进行血流量和搏动指数（pulsatility index，PI）的多因素分析。结果 TTFM技术提示，791支移植物中有严重质量问题的移植血管5支，均手术证实并加以改正。可能影响移植物血流量的主要因素为LAD远端直径、LIMA直径、心肌梗死位置、LAD近端狭窄程度、反流量百分比（percentage of insufficiency）、左心室舒张期末内径、手术方式（体外循环和非体外循环）；影响P1值的主要因素为LAD远端直径、反流量百分比和手术方式。结论 TTFM在判断CABG移植物状态时具有一定的诊断价值。多种因素均可影响移植物的血流量和P1值，应考虑主要影响因素以及临床表现来提高TTFM诊断技术错误的敏感性。     

Cognitive self-assessment one year after on-pump and off-pump coronary artery bypass grafting

BACKGROUND: Coronary artery bypass grafting (CABG) is associated with significant cerebral morbidity. This is usually manifested as cognitive decline and may be caused by cardiopulmonary bypass. The primary objective of this study was to explore whether patients report more cognitive failures 1 year after CABG than preoperatively. Secondary objectives were to evaluate whether there is a difference in reported cognitive failures between patients undergoing on-pump and off-pump CABG and whether a difference between CABG patients and healthy control subjects exists. Finally the relation between objective and subjective cognitive functioning was quantified. METHODS: In this prospective study, the Cognitive Failures Questionnaire (CFQ) was assigned preoperatively and 1 year postoperatively to 81 patients who were randomly assigned to undergo off-pump (n = 45) or on-pump (n = 36) CABG. A control sample of 112 age-matched healthy subjects was included who were administered the CFQ once. RESULTS: No difference was found in the total CFQ score (p = 0.222) and CFQ worry score (p = 0.207) between 1 year after CABG and before CABG. There was no difference between on-pump and off-pump CABG (total score, p = 0.458; worry score, p = 0.563). A significant difference was found in CFQ total score between CABG patients and control subjects (p < 0.001), with control subjects reporting more cognitive failures than CABG patients. Finally, patients who showed cognitive decline in the Octopus trial did not have a higher CFQ total score (p = 0.671) and CFQ worry score (p = 0.772) than patients without cognitive decline 1 year after CABG. CONCLUSIONS: The present findings suggest that CABG does not result in a substantial proportion of patients with subjectively experienced cognitive decline 1 year after the procedure, irrespective of the type of surgical technique (on-pump versus off-pump).     

Urgent off-pump coronary artery bypass grafting

OBJECTIVES: The use of off-pump coronary artery bypass grafting (CABG) has become widespread, since it has proven less invasive and to promote early recovery. In this study, we investigated the efficacy of off-pump CABG in patients in the evolving phase of acute myocardial infarction. METHODS: Retrospective chart review was carried out for patients undergoing urgent isolated off-pump and on-pump CABG at Shin-Tokyo Hospital Group between January 1991 and June 2001. The patients' demographic, operative data, and postoperative results were collected. RESULTS: The off-pump group consisted of 19 males and 11 females with a mean age of 72.0 years and the on-pump group of 91 males and 38 females with a mean age of 64.3 years. Preoperative use of intraaortic balloon pumping and preoperative shock was more frequently observed in the on-pump group. The mean number of distal anastomoses was 3.1 +/- 0.9 in the off-pump group and 3.2 +/- 1.1 in the on-pump group (p = NS). Intubation time (18.5 vs 32.9 hours), ICU stay (3.4 vs 4.9 days), and postoperative stay (13.5 vs 24.3 days) were significantly shorter in the off-pump group than in the on-pump group (P < 0.05). The frequency of the major complications was significantly lower in the off-pump group (9/30, 30%) than the on-pump group (65/129, 50.4%), especially for postoperative low output syndrome (p < 0.05). Multivariate analysis demonstrated a significant reduction in the recovery period by use of off-pump CABG. Early follow-up results were similar between the two groups, in terms of late cardiac events and survival. CONCLUSION: Urgent off-pump CABG is safe and provides early recovery, provided that the patient's intraoperative hemodynamics are taken into account.     

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.     

高龄患者体外与非体外循环冠状动脉旁路移植术后早期呼吸功能的比较

目的探讨体外循环冠状动脉旁路移植术(on-pump coronary artery bypass grafting,on-pump CABG)与非体外循环冠状动脉旁路移植术(off-pump coronary artery bypass grafting,off-pump CABG)对高龄(≥70岁)患者术后早期呼吸功能的影响。方法将2000年12月至2006年2月在我科接受on-pump CABG和off-pump CABG的高龄冠心病患者分为两组(on-pump组和off-pump组),每组30例,分别进行围术期动脉血气分析和肺功能的测量。结果两组患者术前肺功能和动脉血气指标差异无统计学意义;术后第1d和第3d红细胞压积(Hematocrit,Hct)值、术后1~3d动脉血氧分压值、术后第4~6d的用力肺活量(forced vital capacity,FVC)、第1秒用力呼气量(first second forced expiratory volume,FEV1.0)、一秒率(FEV1.0/FVC%)等on-pump组均低于off-pump组(P<0.05),术后平均带气管内插管时间和住院时间on-pump组长于off-pump组(P<0.05)。结论高龄冠心病患者施行off-pump CABG较on-pump CABG术后早期呼吸功能恢复良好。     

Does off‐pump coronary artery bypass grafting beneficially affect renal function?

BACKGROUND: Off-pump coronary artery bypass grafting (CABG) has been reported to beneficially affect renal function, but this remains to be confirmed. The purpose of the present paper was to study the effects of off-pump CABG on renal function and analyse predictors of postoperative renal impairment in patients who received off-pump CABG. METHODS: A total of 451 patients who underwent isolated CABG between January 1999 and August 2003 were retrospectively studied. No patient was receiving dialysis. A total of 300 patients (228 men) underwent off-pump CABG (off-pump group) and 151 patients (104 men) underwent on-pump CABG (on-pump group). Perioperative serum creatinine levels and creatinine ratios (peak postoperative creatinine level/preoperative creatinine level) were compared between the groups. RESULTS: Renal impairment (serum creatinine >1.5 mg/dL) developed postoperatively in 12.7% of the off-pump group and 18.5% of the on-pump group (P = 0.1). The creatinine ratio was significantly lower in the off-pump group (1.2 +/- 0.4) than in the on-pump group (1.4 +/- 0.7, P = 0.003). Logistic regression analysis demonstrated that the strongest predictors of postoperative renal impairment in off-pump CABG were left ventricular dysfunction (odds ratio 10.8) and multivessel grafting (odds ratio 4.3). CONCLUSIONS: Off-pump CABG provides better renal protection than on-pump CABG. However, perioperative renal function should be closely monitored in patients who have left ventricular dysfunction or who undergo multivessel grafting, even when off-pump CABG is performed.     

Off-pump coronary artery bypass grafting for patients with three-vessel disease

BACKGROUND: Off-pump coronary artery bypass grafting (CABG) has been performed since 1996 in our institute, and its application has recently been expanded to patients with three-vessel disease. A study was performed to clarify the benefit of off-pump CABG for patients with three-vessel disease. METHODS: Between June 1, 1991 and September 30, 2001, a total of 1089 patients with three-vessel disease (832 men and 257 women; mean age, 64.0 +/- 9.1 years) underwent on-pump CABG. After 1997, a total of 310 patients with three-vessel disease (223 men and 87 women; mean age, 68.8 +/- 8.6 years) underwent off-pump CABG. Data of the historical cohort of on-pump CABG and the concurrent cohort of off-pump CABG were analyzed retrospectively. RESULTS: The 2 groups were age and gender matched. Significant comorbidities were more often observed in the off-pump group than in the on-pump group. The mean number of bypass grafts in the off-pump versus on-pump CABG was 3.3 vs 3.7, P <.0001. The mean intubation period, intensive care unit stay, and postoperative hospital stay were 7.9 vs 11.7 hours, 2.2 vs 3.0 days, and 14.5 vs 17.5 days, respectively (P <.0001). In-hospital mortality rate (0.6% vs 1.2%, respectively) and morbidity rates (10.3% vs 12.9%, respectively) were not significantly different. After surgery, calculated event-free rates at 2 years were 93.3% vs 91.9%, respectively; P = not significant. CONCLUSIONS: In patients with multivessel disease, off-pump CABG provided early recovery, and its complication rates and early follow-up results were equivalent to on-pump CABG.     

Outcomes experience with off-pump coronary artery bypass surgery in women

BACKGROUND: It has been well documented that women have higher morbidity and mortality rates than men following coronary artery bypass graft (CABG) surgery. In view of this evidence, we investigated the following question: compared with on-pump CABG surgery, is there benefit to off-pump CABG surgery in women? METHODS: Our investigation analyzes patient mortality and 13 procedure complications controlling for 35 variables representing patient characteristics and comorbid conditions, and for procedure characteristics for a population of 16,871 consecutive women undergoing off-pump and on-pump CABG surgery at 78 hospitals for the period January 1998 to June 2001. RESULTS: Mean comparisons reveal that the mortality rate for women undergoing off-pump CABG surgery is nearly a percentage point lower than for women undergoing on-pump surgery (3.12 vs 3.90; p = 0.052). The complication rates for all complications analyzed (shock/hemorrhage, neurologic, cardiac, respiratory, renal, acute renal failure, adult respiratory distress syndrome, implant infection, postoperative infection, septicemia, pneumonia, and peripheral vascular) were lower for women off-pump than women on-pump with the exception of mechanical complications. Logistic regression results reveal, after controlling for 35 relevant patient characteristics, comorbid conditions and procedure characteristics, that women undergoing on-pump CABG surgery experience a 42% higher mortality rate (p = 0.0239) than women undergoing off-pump CABG surgery. CONCLUSIONS: Evidence suggests that off-pump CABG surgery may be better for women than on-pump CABG surgery because it appears to reduce mortality and respiratory complications, shorten lengths-of-stay, and increases discharges directly home. None of the 12 other complications investigated demonstrated an advantage for women undergoing on-pump surgery relative to those receiving off-pump surgery.     

Postoperative inflammatory reactions after coronary artery bypass grafting performed on-pump with preceding glucocorticoid therapy compared with those after grafting performed off-pump

BACKGROUND: Compared with conventional coronary artery bypass graft surgery (CABG) using cardio-pulmonary bypass, less postoperative acute inflammatory responses are expected in off-pump CABG. Therefore, we retrospectively studied the difference in postoperative inflammatory reactions between on-pump and off-pump surgical groups. METHODS : We selected 15 patients for on-pump and 19 for off-pump groups, respectively, from the past 3 years. One gram of methylpredonisolone was administered before institution of cardiopulmonary bypass only in the on-pump group. The white blood cell count and the level of C-reactive protein were compared in both groups for 10 days postoperatively. RESULTS : The white blood cell count reached a maximum in each group 2 days after surgery. However the values were significantly greater in the on-pump group than in the off-pump group at postoperative days 3 through 6. The level of C-reactive protein was also increased postoperatively in each group. In the off-pump group without receiving any steroid therapy, the values were greater than in the on-pump group on postoperative days 1 through 6. CONCLUSIONS :In off-pump CABG, the level of C-reactive protein increases significantly in the postoperative period.     

Recent unstable angina and off-pump coronary artery bypass grafting is not related to postoperative atrial fibrillation

OBJECTIVE: Atrial fibrillation (AF) is the most frequently encountered postoperative arrhythmic complication after coronary artery bypass grafting (CABG). The purpose of the present study was to investigate the incidence and predictors of postoperative AF in patients with stable and unstable angina pectoris undergoing on-pump and off-pump CABG procedures. DESIGN: One hundred and seventeen stable, unstable on-pump and off-pump CABG patients were included in the present study. Holter data were collected 1 day before the operation to the 2nd postoperative day. AF was registered as positive if any AF event occurred. RESULTS: The overall incidence of postoperative AF and sustained AF was 31.6 and 25.6%, respectively. Postoperative AF incidences in stable on-pump, unstable on-pump and stable off-pump patients were 29.5, 39.0 and 25%, respectively (p = 0.412). Patients with AF had compromised postoperative haemodynamic function, greater need of inotropic support and antiarrhythmic medication, and longer intensive care unit (ICU) stays. CONCLUSION: Post-CABG AF is associated with more complicated postoperative outcome. Recent unstable angina and off-pump procedure is not related to the occurrence of post-CABG AF.     

Operative mortality after conventional versus coronary revascularization without cardiopulmonary bypass.

OBJECTIVE: Off-pump coronary artery bypass (CABG) is a safe revascularization option with comparable or superior results to the conventional on-pump CABG. However, comparative analysis of the type of surgical approach on the mortality rate is largely unknown. This study sought to investigate whether CABG without cardiopulmonary bypass (off-pump CABG) is associated with lower operative mortality than the conventional on-cardiopulmonary bypass (on-pump) approach. METHODS: From October 1998 to June 2001, off-pump CABG was performed on 2477 patients and on-pump CABG was performed on 3077 patients. The patients undergoing off-pump CABG were randomly matched to on-pump patients via propensity score. Seventy-four percent of the off-pump CABG patients were matched with on-pump patients via propensity scores. A logistic regression model was used to test the difference in the postoperative mortality rate between off-pump CABG and on-pump CABG, controlling the correlation between matched sets. A multiple logistic regression model predicting the risk of mortality adjusted by risk factors of mortality and operation type was computed. RESULTS: Results from the general estimating equation showed that patients who had on-pump CABG were 1.6 (95% confidence intervals (CI)=1.2-2.0, P<0.01) times more likely to die during the first 30 days after surgery than patients who had off-pump CABG. Independent predictors of 30-day mortality identified from the multiple logistic model included on-pump CABG (versus off-pump CABG), advanced age, female gender, carotid artery disease, chronic renal failure, depressed ejection fraction, reoperative CABG, preoperative intraaortic balloon counterpulsation, and recent myocardial infarction. CONCLUSION: Excellent clinical results and a lower operative mortality rate can be achieved with the off-pump CABG technique compared with the conventional on-pump approach.     

冠心病合并慢性阻塞性肺疾病患者冠状动脉旁路移植术疗效分析

目的 评价冠心病合并慢性阻塞性肺疾病（COPD）患者行冠状动脉旁路移植术（CABG）的临床效果。方法 回顾性分析我院1998年1月～2004年12月27例冠心病合并COPD患者接受CABG的临床资料，根据术中采用不同的方法分为非体外循环CABG组（off—pump组，18例）和体外循环CABG组（on—pump组，9例），并在不同时间点对两组患者的氧合指数（PaO2／FiO2）、呼吸功能相关指标、细胞间黏附分子1（ICAM-1）的变化及肺泡灌洗液中中性粒细胞数量进行比较分析。结果 两组患者均无手术死亡；术后14d off—pump组死亡1例，死于呼吸衰竭；on—pump组发生呼吸系统并发症较off—pump组多。体外循环（CPB）30min后／手术开始on—pump组患者的PaO2／FiO2高于off—pump组，而在术后6h和12h却明显低于off—pump组（P〈0．05）；手术开始／CPB30min到术后24h血浆中ICAM-1的浓度off—pump组均低于on—pump组（P〈0．05）；肺泡灌洗液中中性粒细胞数on—pump组均高于off—pump组（P〈0．05）。结论 Off—pump CABG对肺的气体交换功能损伤较小，术后肺部并发症发生率较低，因此更适合于冠心病合并COPD的患者。     

Does off-pump surgery offer benefit in high respiratory risk patients? A respiratory risk stratified analysis in a propensity-matched cohort.

OBJECTIVE: The role of off-pump surgery in high respiratory risk patients remains unclear. In this study, we aim to evaluate the effect of off-pump surgery on high respiratory risk patients. METHODS: To achieve comparative groups, a five digit propensity score matching with 18 pre-operative variables was performed on 4406 consecutive CABG patients operated between January 2000 and September 2003. Respiratory risk stratification was performed with the following variables: (1) FEV(1)<65% of predicted, (2) patients>75 years old, (3) history of current smoking, (4) body mass index more than 40 kg/m(2) and (5) NYHA class IV dyspnoea in combination with current respiratory medication. The presence of two or more variables defined high risk. The primary end point was post-operative ventilation time. We also compared alveolar arterial gradients (A-a gradient) on admission to ITU, 2 and 4h using Friedman rank time analysis. RESULTS: We matched 1353 off-pump patients with 1353 unique on-pump patients. Respiratory risk stratified selection resulted in 73 off-pump and 55 on-pump high-risk patients. In the off-pump group, four (5.5%) patients had more than two selection criteria, compared to one (1.8%) for on-pump patients (p=0.29). The off-pump group had more patients with FEV1<65% compared to on-pump: 65 (89.0%) versus 40 (72.7%); p=0.017. The median ventilation time was significantly shorter for off-pump patients (7h [IQR: 5-14] vs 12h [IQR: 7-18], p=0.003). In the off-pump group, three (4.1%) patients had a ventilation time>48 h compared to eight (14.6%) in the on-pump group, p=0.037. A-a gradient measurements on admission to ITU were lower in off-pump patients (median: 182.3 [IQR: 126.6-216.2]) compared to on-pump patients (median: 194.7 [IQR 139.7-245.4], p=0.064). CONCLUSION: Off-pump surgery offers benefit to high respiratory risk patients by reducing post-operative ventilation time. Off-pump patients also have lower A-a gradients in the early post-operative period but this failed to reach significance.     

Off-pump coronary artery bypass grafting in patients with end-stage renal disease on hemodialysis

BACKGROUND: Coronary artery bypass grafting (CABG) for hemodialysis patients is high risk compared with other patient groups. The aim of this study was to analyze the potential benefits of off-pump CABG for hemodialysis patients. METHODS: From April 1994 through December 2000, 26 hemodialysis patients underwent CABG. The off-pump group consisted of 15 patients operated on without a pump and the on-pump group consisted of 11 patients operated on with a pump. RESULTS: There was no difference between the two groups with regard to mean age, mean number of diseased vessels and mean number of anastomoses per patient. No patient died in either group during hospitalization. The postoperative complication rate was low in both groups. The postoperative ventilation time was shorter in the off-pump group (8.5 vs 26.1 hours, p < 0.001, respectively [off-pump group vs on-pump group]). The length of ICU stay was shorter in the off-pump group (1.7 vs 3.5 days, p = 0.01, respectively [off-pump group vs on-pump group]). The medial cost was lower in the off-pump group (26,200.80 dollars versus 44,024.10 dollars p = 0.0001 respectively [off-pump group vs on-pump group]). CONCLUSIONS: Off-pump CABG provided excellent less-invasive cardiac surgical results for dialysis patients.     

Effect of off-pump and on-pump coronary artery bypass grafting on renal function

BACKGROUND: Coronary artery bypass grafting (CABG) with cardiopulmonary bypass (CPB) has the risk of renal dysfunction. The cause of renal dysfunction after CPB is multifactorial, such as nonpulsatile flow, renal hypoperfusion, hypothermia, and duration of CPB. This study compared off-pump technique with on-pump technique on renal function in patients who underwent CABG. METHODS: Sixty patients with normal preoperative renal functions undergoing CABG were randomly assigned to conventional revascularization with CPB (on-pump) or beating heart revascularization (off-pump). Renal functions were assessed up to 10 days postoperatively. RESULTS: Creatinine clearance was found to be significantly higher in the off-pump group than in the on-pump group (p<.05). The off-pump group had significantly less increase in creatinine levels when compared with the on-pump group (p<.05). The free water clearance values decreased similarly in both groups; however, the recovery was more prompt in the off-pump group (p<.05). No significant differences were found in the prevalence of postoperative hemodialysis. CONCLUSION: The off-pump technique may provide a positive contribution and sufficient protection on postoperative renal functions in patients undergoing CABG.