Direct myocardial revascularization without extracorporeal circulation. Experience in 700 patients

Beating heart totally endoscopic coronary artery bypass

Robotic coronary surgery has the potential advantages of decreasing surgical trauma, decreasing postoperative recovery period compared to conventional surgery, and provides surgeons the possibility to offer a competitive tool in response to the technological improvements of interventional cardiology. Since 2007, many technical issues have been solved by the new generation of robotic devices, allowing a safer, more reliable and reproducible totally endoscopic coronary bypass, on the beating heart.

MINI-off-pump coronary artery bypass graft: long-term results

In an effort to decrease the risks and costs associated with coronary artery bypass graft, in 1978 we repopularized off-pump coronary artery bypass graft (OPCABG) and expanded the technique, addressing lesions of the circumflex system and applying it to diverse clinical scenarios. In this article we describe our experience with 40 patients who received coronary revascularization through a MINI-OPCABG (Benetti technique) operation. Follow-up was achieved by direct communication with the patients or their family during 144 months. The interviews investigated survival, symptoms, long-term medical management and the need for reintervention. This group of patients had no operative mortality and 18 patients (45%) were extubated in the operating room. One patient (2.5%) experienced a perioperative myocardial infarction. During follow-up, two patients received percutaneous coronary intervention, one in the right coronary artery, the other in the circumflex system. A total of seven patients (17.5%) died. Overall, cumulative patient survival at 144 months was 82.5% (33 cases). Of the seven patients who died, four (10.0%) died of cardiac causes and 68.5% were free of symptoms. Technological advances will help to overcome the anatomical difficulties of this surgical technique, and when simplified, will allow it to be reproduced, offering patients a minimally invasive surgical alternative for the treatment of coronary disease, avoiding the limitations of percutaneous transluminal coronary angioplasty and coronary artery bypass graft.

Robotically assisted atraumatic coronary artery bypass: a feasible option for off-pump coronary surgery

This retrospective study of the largest single center experience (100 patients) with off-pump robotically assisted coronary procedures in the United Kingdom (April 2002-June 2008) aimed to rationalize patient selection, describe the technique, and determine the learning curve, technical feasibility and operative outcome of robotically assisted Atraumatic Coronary Artery Bypass (ACAB). Selected patients underwent either a robotic Totally Endoscopic Coronary Artery Bypass (12) or robotically assisted ACAB (88) using a standard Da Vinci robot with three arms. A fifth of all cases had percutaneous interventions as part of a hybrid strategy. The majority of patients were overweight men. After one hundred robotic coronary procedures, this operation is now performed as part of a routine theatre list. The mean operative and total procedure times for robotically assisted atraumatic procedures were 157 and 238 min, respectively. These measurements were significantly less in the atraumatic than the totally endoscopic group with a 34.3 and 20.6% reduction, respectively (P < 0.001; equal variance not assumed). The procedural learning curve was short and independent from internal thoracic artery harvesting. We have proven conclusively that robotically assisted ACAB is feasible, more so than the totally endoscopic procedure in this particular setting. Even in the absence of an ideal stabilizer device, this procedure causes minimal disruption to the daily operating room schedule. We have also proven that body mass index is a weak predictor of the ease of robotic internal thoracic artery harvesting and should not affect patient selection.

Off-pump coronary artery bypass surgery and acute kidney injury: a meta-analysis of randomized controlled trials

BACKGROUND AND OBJECTIVES

Off-pump coronary artery bypass grafting (CABG) has been advocated to cause less inflammation, morbidity, and mortality than the more traditional on-pump technique. This meta-analysis compares these two surgical techniques with respect to causing acute kidney injury (AKI).

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This study searched for randomized controlled trials in MEDLINE and abstracts from the proceedings of scientific meetings through February 2010. Included were trials comparing off-pump to on-pump CABG that reported the incidence of AKI, as defined by a mixture of criteria including biochemical parameter/urine output/dialysis requirement. Mortality was evaluated among the studies that reported kidney-related outcomes. For primary and subgroup analyses, fixed-effect meta-analyses of odds ratios (OR) were performed.

RESULTS

In 22 identified trials (4819 patients), the weighted incidence of AKI in the on-pump CABG group was 4.0% (95% confidence interval [CI] 1.8%, 8.5%), dialysis requirement 2.4% (95% CI 1.6%, 3.7%), and mortality 2.6% (95% CI 1.6%, 4.0%). By meta-analysis, off-pump CABG was associated with a 40% lower odds of postoperative AKI (OR 0.60; 95% CI 0.43, 0.84; P = 0.003) and a nonsignificant 33% lower odds for dialysis requirement (OR 0.67; 95% CI 0.40, 1.12; P = 0.12). Within the selected trials, off-pump CABG was not associated with a significant decrease in mortality.

CONCLUSIONS

Off-pump CABG may be associated with a lower incidence of postoperative AKI but may not affect dialysis requirement, a serious complication of cardiac surgery. However, the different definitions of AKI used in individual trials and methodological concerns preclude definitive conclusions.

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

In an attempt to advance the surgical treatment of coronary artery disease, surgeons sought a way to offer the proven benefits of coronary revascularization and avoid the side effects of cardiopulmonary bypass by performing revascularization in the beating heart (off-pump coronary artery bypass). This review will describe the development and refinement of the technique, pitfalls to its widespread adoption, and an up-to-date assessment of current results.

On-pump versus off-pump coronary-artery bypass surgery

BACKGROUND

Coronary-artery bypass grafting (CABG) has traditionally been performed with the use of cardiopulmonary bypass (on-pump CABG). CABG without cardiopulmonary bypass (off-pump CABG) might reduce the number of complications related to the heart-lung machine.

METHODS

We randomly assigned 2203 patients scheduled for urgent or elective CABG to either on-pump or off-pump procedures. The primary short-term end point was a composite of death or complications (reoperation, new mechanical support, cardiac arrest, coma, stroke, or renal failure) before discharge or within 30 days after surgery. The primary long-term end point was a composite of death from any cause, a repeat revascularization procedure, or a nonfatal myocardial infarction within 1 year after surgery. Secondary end points included the completeness of revascularization, graft patency at 1 year, neuropsychological outcomes, and the use of major resources.

RESULTS

There was no significant difference between off-pump and on-pump CABG in the rate of the 30-day composite outcome (7.0% and 5.6%, respectively; P=0.19). The rate of the 1-year composite outcome was higher for off-pump than for on-pump CABG (9.9% vs. 7.4%, P=0.04). The proportion of patients with fewer grafts completed than originally planned was higher with off-pump CABG than with on-pump CABG (17.8% vs. 11.1%, P<0.001). Follow-up angiograms in 1371 patients who underwent 4093 grafts revealed that the overall rate of graft patency was lower in the off-pump group than in the on-pump group (82.6% vs. 87.8%, P<0.01). There were no treatment-based differences in neuropsychological outcomes or short-term use of major resources.

CONCLUSIONS

At 1 year of follow-up, patients in the off-pump group had worse composite outcomes and poorer graft patency than did patients in the on-pump group. No significant differences between the techniques were found in neuropsychological outcomes or use of major resources. (ClinicalTrials.gov number, NCT00032630.).

Robotic manipulators in cardiac surgery: the computer-assisted surgical system ZEUS

Minimally invasive strategies continue to evolve in cardiac surgery. Robotic-assisted systems have been introduced recently, to increase the precision of endoscopic coronary surgery. This report describes the experimental and clinical use of the computer-assisted robotic system ZEUS for endoscopic coronary artery bypass anastomoses. The ZEUS system consists of three interactive robotic arms and a control unit, allowing the surgeon to move the instrument arms in a scaled-down mode. The third arm (AESOP) positions the endoscope under voice control. The present study demonstrates the feasibility of endoscopic coronary artery bypass grafting using a computer-assisted surgical robotic system on the arrested heart, as well as on the beating heart in selected patients. However, robotic-assisted cardiac surgery is still developing, and tremendous efforts are still required to establish a routine procedure.

Temporal pattern of strokes after on-pump and off-pump coronary artery bypass graft surgery

BACKGROUND

The incidence of strokes has not decreased after coronary artery bypass graft surgery (CABG). The purpose of this study is to identify incidence, risk factors, and temporal pattern of strokes after on-pump and off-pump CABG.

METHODS

We analyzed 2,516 consecutive patients who underwent first elective isolated CABG. The primary endpoint was strokes within 30 days. The temporal onset of the deficits was classified by consensus as either an "early stroke," which is present just after emergence from anesthesia, or a "delayed stroke," which is present after first awaking from surgery without a neurologic deficit.

RESULTS

More than half of strokes (29 of 46; 63%) were delayed strokes. Patients undergoing off-pump CABG had significantly lower risk of early stroke (0.1% versus 1.1%, p = 0.0009), whereas the incidence of delayed strokes was not different significantly (0.9% versus 1.4%, p = 0.3484) between patients undergoing on-pump and off-pump CABG. In multivariate analyses, undergoing off-pump CABG was an independent protective factor for all strokes (relative risk 0.29, 95% confidence interval: 0.14 to 0.56, p = 0.0005) and early strokes (relative risk 0.05, 95% confidence interval: 0.003 to 0.24, p < 0.0001), but it was not an independent protective factor for delayed strokes (relative risk 0.54, 95% confidence interval: 0.24 to 1.17, p = 0.1210).

CONCLUSIONS

Undergoing off-pump CABG reduces the incidence of perioperative stroke mainly by minimizing early strokes; however, the risk of delayed strokes is not different between patients undergoing on-pump and off-pump CABG.

[Drug-eluting stents: implications for modern coronary revascularization]

Despite considerable data and years of experience in the field of coronary interventions and coronary surgery existing guidelines, which are still valid in the era of drug-eluting stents (DES), are often not followed. An increasing number of patients are treated with DES implantations against current recommendations. Due to antiplatelet therapy this impedes the planning and execution of additional invasive procedures that might be necessary after DES implantation and results in higher risks, if delaying treatment is not possible. As alternatives to stent implantation, coronary surgery nowadays offers a full range of individual treatment options which are highly effective and durable. They can be performed at low risk and do not interfere with subsequent invasive therapies. Patients suffering from relevant coronary artery disease and who are in need of additional invasive treatment should be considered for coronary surgery rather than stent implantation. If current guidelines are followed more closely, DES implantations and their accompanying drawbacks could be significantly reduced.

Simultaneous off-pump coronary artery bypass graft and nephrectomy

We report the one-stage surgical management of a 68-year-old patient with renal cell carcinoma and serious hematuria combined with coronary artery disease and unstable angina. After the accomplishment of coronary revascularization without cardiopulmonary bypass, we proceeded to nephrectomy and resection of the renal tumor at the same time. The patient's postoperative course was uneventful, and at 17 months of follow-up, the patient showed no signs of recurrence. To the best of our knowledge, such a case has never been reported before in the literature.

Off-Pump Coronary Artery Bypass Grafting is Associated With Reduced Operative Mortality and In-Hospital Adverse Events in Patients With Left Main Coronary Artery Disease

OBJECTIVE

: Left main coronary artery disease (LMD) is a known risk factor for perioperative complications. This study compares off-pump coronary artery bypass (OPCAB) versus on-pump coronary artery bypass (ONCAB) grafting, CABG, with respect to in-hospital death, stroke, myocardial infarction, and major adverse cardiac events (MACE) in CABG patients with and without LMD.

METHODS

: Among 13,108 consecutive isolated patients with CABG treated from 1997 to 2007, 2891 patients (22.1%) were preoperatively found to have LMD. Of 5917 patients with OPCAB, 1276 (21.6%) had LMD, whereas among patients with ONCAB, 1615 of 7191 (22.5%) had LMD. Surgery type, LMD, and their interaction were examined for their impact on operative mortality, stroke, myocardial infarction, and MACE via multiple logistic regression models and adjusted odds ratios (AOR).

RESULTS

: Utilization of OPCAB for coronary revascularization in patients with LMD disease gradually increased from an initial low of 1.3% of patients in 1997 to a peak of 80.8% in 2007. OPCAB was associated with reduced incidence of stroke (AOR = 0.51, P < 0.001) and MACE (AOR = 0.66, P = 0.002), whereas LMD was associated with an increased incidence of MACE (AOR = 1.24, P = 0.038). No interactions between surgery type and LMD existed, meaning that the 2 conditions did not combine in any way to modify outcomes.

CONCLUSIONS

: Patients with LMD are more likely to suffer a MACE event than those without LMD. Off-pump coronary artery bypass grafting is marginally associated with lesser risk of operative mortality and significantly associated with less stroke and overall MACE when compared with ONCAB. This benefit of OPCAB is similar for patients with and without LMD.

Off-pump coronary artery bypass grafting through left antero-lateral thoracotomy (thora-cab) - case report and review of literature

We report the first case of off-pump complete myocardial revascularization through antero-lateral thoracotomy (Thora-CAB) in Middle-East. 69 year old gentleman having angina pectoris for last three years with severe double vessel disease involving the left anterior descending artery (95% proximal lesion) and the circumflex system (80% mid circumflex lesion with significant osteal disease in obtuse marginal) and insignificant disease in right coronary artery with moderate left ventricular impairment underwent Thora-CAB. Post-operatively, he had minimal pain, quick symptomatic improvement and no complications. He was discharged home on 5th post-operative day. This indicates that the thoracotomy approach is safe and practical for CABG. It is well tolerated hemodynamically with no/ minimal post-operative morbidity.

Left Heart Pump-Assisted Beating Heart Coronary Surgery in High-Risk Patients

A simple technique of left ventricular assistance, offering the advantages of both cardiopulmonary bypass and off-pump revascularization, was adopted for high-risk patients. It was used in 56 patients with critical left main stenosis and occluded right coronary artery, severely reduced ejection fraction and/or unstable angina. All patients underwent complete and successful myocardial revascularization (3.4 grafts per patient). Weaning from the pump was uncomplicated, and none required conversion to full cardiopulmonary bypass.

Coronary Artery Revascularisation : Past, Present and Future

The high prevalence of coronary artery disease has inspired the development of technologies and techniques for coronary revascularisation, including coronary artery bypass grafting (CABG) and percutaneous coronary interventions (PCI). PCI have witnessed the impact of innovation with newer hardware and drug eluting stents (DES). DES have indisputably reduced restenosis, however there is an emerging concern over the risk of late stent thrombosis associated with their use. We discuss the limitations of the current generation DES and review advances in the stent technology. The technology used in CABG has improved, resulting in off-pump coronary artery bypass (OPCAB), endoscopic, video-assisted, and robot-assisted CABG with automated one-shot distal anastomotic devices being used increasingly. The difference in adverse outcomes between CABG and PCI continues to decline and the future may witness a close collaboration between the two.

Robotically Assisted Beating Heart Totally Endoscopic Coronary Artery Bypass (TECAB). is There a Future?

Objective

Since the introduction of beating heart totally endoscopic coronary artery bypass (TECAB), approximately 400 patients have undergone the procedure worldwide. Despite satisfactory results and reduced morbidity, the procedure has not gained wide acceptance. This report describes the authors’ experience of beating heart TECAB with robotic assistance and the potential adoption of this technique for the future.

Methods

Between July 2004 and December 2005, 93 patients underwent successful for beating heart TECAB (47 males and 46 females). Mean age was 67.4 + 12.3 years. Fifteen (13.8%) were excluded or converted intraoperatively to thoracotomy for completion of procedure. The procedure was performed through port incisions for the robotic arms and the endostabilizer. Single or bilateral internal thoracic arteries were used as conduits. Anastomoses were done using surgical U-clips. Eighteen (19.4%) patients underwent planned hybrid revascularization. Eighty-four (90.3%) patients underwent computed tomography or conventional angiography.

Results

Details of 93 completed revascularization cases are summarized in the tables. No in-hospital mortality, myocardial infarction, or CVA was noted. Mean operative time was 272.6 + 128.9 minutes (median, 270 minutes). Mean anastomotic time was 13.8 + 3.7 minutes. Mean length of hospital stay was 3.4 + 2.0 days (median, 3 days). At the time of study, 122 of 122 (100%) grafts were found to be patent.

Conclusions

Single- and multivessel beating heart TECAB with or without hybrid revascularization may offer a less invasive approach in a selected group of 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.

Off-pump versus on-pump coronary artery bypass graft surgery: differences in short-term outcomes and in long-term mortality and need for subsequent revascularization

BACKGROUND

Off-pump coronary artery bypass graft surgery (OPCAB) has been performed for many years, but its use is increasing in frequency, and it remains an open question whether OPCAB is associated with better outcomes than on-pump coronary artery bypass graft (CABG) surgery.

METHODS AND RESULTS

New York State patients who underwent either OPCAB with median sternotomy (13 889 patients) or on-pump CABG surgery (35 941 patients) between 2001 and 2004 were followed up via New York databases. Short- and long-term outcomes were compared after adjustment for patient risk factors and after patients were matched on the basis of significant predictors of type of CABG surgery. OPCAB had a significantly lower inpatient/30-day mortality rate (adjusted OR 0.81, 95% confidence interval [CI] 0.68 to 0.97), lower rates for 2 perioperative complications (stroke: adjusted OR 0.70, 95% CI 0.57 to 0.86; respiratory failure: adjusted OR 0.80, 95% CI 0.68 to 0.93), and a higher rate of unplanned operation in the same admission (adjusted OR 1.47, 95% CI 1.01 to 2.15). In the matched samples, no difference existed in 3-year mortality (hazard ratio 1.08, 95% CI 0.96 to 1.22), but OPCAB patients had higher rates of subsequent revascularization (hazard ratio 1.55, 95% CI 1.33 to 1.80). The 3-year OPCAB and on-pump survival rates for matched patients were 89.4% and 90.1%, respectively (P=0.20). For freedom from subsequent revascularization, the respective rates were 89.9% and 93.6% (P<0.0001).

CONCLUSIONS

OPCAB is associated with lower in-hospital mortality and complication rates than on-pump CABG, but long-term outcomes are comparable, except for freedom from revascularization, which favors on-pump CABG.

Deleterious effects of cardiopulmonary bypass in coronary artery surgery and scientific interpretation of off-pump's logic

Cardiopulmonary bypass (CPB) has been suggested to be a cause of complex systemic inflammatory response that significantly contributes to several adverse postoperative complications. In the last few years, off-pump coronary artery bypass grafting (OPCAB) has gained widespread attention as an alternative technique to conventional on-pump coronary artery bypass grafting (ONCAB). However, a degree of uncertainty regarding the relative merits of ONCAB and OPCAB continues to be a significant issue. Surgeons supporting off-pump surgery, state that the avoidance of the CPB leads to significantly reduced myocardial ischemia-reperfusion injury, postoperative systemic inflammatory response and other biological derangements, a feature that may improve the clinical outcomes. However, perfection in perioperative care, surgical technique and methods of attenuating the untoward effects of CPB has resulted in better clinical outcome of ONCAB as well. Possible reasons of these controversial opinions are that high-quality studies have not comprehensively examined relevant patient outcomes and have enrolled a limited range of patients. Some studies may have been too small to detect clinically important differences in patient outcomes between these two modalities. We present a review of the available scientific interpretation of the literature on OPCAB with regard to safety, hemodynamic changes, inflammation, myocardial preservation and oxidative stress. We also sought to determine from different reported retrospective and randomized control studies, the initial and the long-term benefits of this approach, despite the substantial learning curve associated with OPCAB.

A study design to assess the safety and efficacy of on-pump versus off-pump coronary bypass grafting: the ROOBY trial

Background Since the late 1960s, coronary artery bypass graft (CABG-only) procedures were traditionally performed using a heart-lung machine on an arrested heart (on-pump). Over the past decade, an increasing number CABG-only procedures were performed on a beating heart (off-pump). Advocates of the off-pump approach expect to reduce many of the adverse side effects related to using the heart-lung machine, while advocates for the on-pump procedure raise concerns related to graft patency rates and long-term event-free survival for the off-pump technique.

Purpose The U.S. Department of Veteran Affairs (VA) Cooperative Studies Program funded a randomized, multicenter clinical trial comparing the clinical and resourcerelated outcomes following on-pump versus off-pump techniques for veterans undergoing a non-emergent CABG-only procedure. The planning committee was faced with several critically important challenges to assure feasibility of study costs and required sample size; generalizability to non-VA surgical practices; and comparability of clinically meaningful results. These challenges are discussed.

Methods This study is a prospective, randomized, multicenter, single blinded (patient) clinical trial that compares on-pump and off-pump techniques for veterans requiring non-emergent CABG-only procedures. There will be 2200 patients randomized at 17 VA Medical Centers when the five-year recruitment period ends on 15 April 2007. There are two primary objectives: a short-term objective to assess the immediate impact of the two techniques on 30-day mortality/morbidity and a long-term objective to assess one-year mortality/morbidity. Major secondary outcomes are one-year graft patency rates and change in neuropsychological assessments from baseline to one year. All patients are assessed at 30 days post-surgery or discharge from the hospital, whichever is latest, and at one-year post-surgery.

Results During planning, several key issues had to be decided. These included 1) choosing primary objectives: a short-term (30-day) and a long-term (one-year) objective were chosen; 2) choosing primary outcome measures: composite measures were selected to ensure sufficient end-points; 3) standardization of surgical techniques: minimal standardization required but guidelines and continuing discussions on both techniques provided; 4) establishing criteria for surgeons and residents for participation: surgeons required to have completed 20 off-pump procedures prior to doing study procedures and residents, in presence of study surgeon, capable of doing either procedure; 5) identifying metrics of cognitive dysfunction sensitive to treatment: a neuropshychologist hired who centrally monitors cognitive functioning testing; and 6) blinding participants of surgical procedure: attempt to blind participants.

Limitations Areas of concern are whether all surgeons sufficiently experienced on the off-pump procedure, should residents have been allowed to do study surgeries, should techniques have been standardized more and were the best neurocognitive tests selected.

Conclusion The study design presented allows for a balanced and fair assessment of the on-pump and off-pump CABG procedures across a diversity of clinical outcomes and resource use metrics. Its results have the potential to influence clinical cardiac surgical practice in the future.

Minimizing Cardiopulmonary Bypass Attenuates Myocardial Damage After Cardiac Surgery

The standard heart-lung machine is deemed a major trigger of systemic inflammatory reactions, potentially inducing organ failure. The strict reduction of blood-artificial surface and blood-air contact might represent meaningful improvements of the extracorporeal technology with respect to organ preservation. In this study, we assessed perioperative myocardial damage by using a novel minimal extracorporeal circuit (MECC) and a conventional cardiopulmonary bypass (CPB) system. Sixty patients scheduled for coronary artery bypass surgery were randomly assigned to either the MECC or the standard CPB system. Myocardial markers were determined by specific immunoassays 6, 12, and 24 hours after CPB initiation. Results were corrected for hemodilution.Demographics, hemodynamics, the number of anastomoses, CPB, and cross-clamp time were comparable between the groups. MECC patients demonstrated significantly lower levels of Troponin T (ng/ml) at 6, 12, and 24 hours (0.07 +/- 0.01 vs. 0.16 +/- 0.04, p < 0.005; 0.12 +/- 0.03 vs. 0.28 +/- 0.08, p < 0.008; 0.21 +/- 0.05 vs. 0.35 +/- 0.09, p < 0.03, respectively) and creatine kinase-MB (U/l) at 6 and 12 hours (22.5 +/- 1.5 vs. 40.6 +/- 3.3, p < 0.0001; 23.3 +/- 3.4 vs. 40.8 +/- 8.0, p < 0.001, respectively). Creatine kinase-MB at 24 hours tended to lower values in the MECC group but did not quite reach statistical significance. The MECC system may not only provide a less invasive solution to meet the requirements during cardiac surgery but also a more organ-preserving alternative to standard CPB.

Revascularization with off-pump coronary artery surgery: what appears new is actually the old rediscovered

The enormous progress in interventional cardiology during the last 10 years has resulted in a major change in the spectrum of patients referred for coronary artery bypass grafting. Several large retrospective analyses, meta-analyses, and the randomized trials that addressed different aspects of ONCAB and OPCAB to date have compared the two surgical strategies. It is suggested that patients may achieve an excellent outcome with either type of procedure, and individuals' outcomes more likely depend on factors other than whether they underwent ONCAB or OPCAB. Nevertheless, there appear to be trends in most studies. These trends include less blood loss and need for transfusion, less myocardial enzyme release up to 24 h, less early neurocognitive dysfunction, and less renal insufficiency after OPCAB and propensity to lower costs, thereafter proving OPCAB to be safe and clinically effective. Here, we review the physiological advantages and clinical outcomes of OPCAB for myocardial revascularization and examine whether either strategy is superior and in which patients.

Starfish™ heart positioner maintains right ventricular function during lateral wall displacement

BACKGROUND

: The authors examined parameters of cardiovascular function using Starfish and deep pericardial sutures (DPS) in a beating heart porcine model and to clarify toleration of right ventricular function with Starfish in lateral wall displacement.

METHODS

: Eight healthy pigs were used. In addition to normal pressure monitor catheters, a Swan-Ganz continuous cardiac output (CO) and end diastolic volume thermodilution catheter was used for precise and quantitative monitoring of the right ventricular function.

RESULTS

: Lateral displacement of the heart with DPS resulted in a significant hemodynamic compromise. Cardiac output and right ventricular ejection fraction (RVEF) decreased from 3.0 ± 0.9 to 2.6 ± 1.0 L/min (P = 0.014) and from 27.9 ± 3.0% to 23.3 ± 4.8% (P = 0.019). With Starfish™, CO and RVEF were maintained from 3.0 ± 0.9 to 3.0 ± 0.9 L/min (P = 0.743) and from 27.9 ± 3.0% to 28.3 ± 3.8% (P = 0.476).

CONCLUSION

: Starfish™ contributed to the stability of hemodynamics by maintaining the right ventricular function. Lateral displacement with PDS resulted in significant hemodynamic compromised compared with Starfish™ and baseline neutral position.

Living with off-pump coronary artery surgery: evolution, development, and clinical potential for coronary heart disease patients

The enormous progress in interventional cardiology during the last 10 years has resulted in a major change in the spectrum of patients referred for coronary bypass surgery. These patients are older and sicker and frequently have had previous percutaneous coronary interventions. Consequently, cardiac surgery is responding by adding new surgical techniques: off-pump open-chest coronary bypass surgery (OPCAB), minithoracotomy bypass surgery, videothoracoscopic (robotic) procedures, etc. Several registries published to date have proved OPCAB to be safe and clinically effective. Randomized studies and meta-analysis research in this field provide scientific support and suggest that myocardial, renal, and neurological functions, amongst others, are better preserved by OPCAB than by classic techniques that use a cardiopulmonary bypass pump (CPB). Moreover, avoidance of CPB yields significantly reduced oxidative stress and systemic inflammatory response. This results in higher safety for ischemic heart disease patients undergoing revascularization, thus offsetting the propensity to lower costs. The present review examines the physiological advantages and clinical outcomes of this simple mode of myocardial revascularisation and evaluates the wider implications arising from its evolution.

Topical lidocaine effectively reduced the increase of systolic blood pressure after side-clamping of the aorta in off-pump cardiac surgery

BACKGROUND

Side-clamping of the ascending aorta during off-pump coronary artery bypass surgery (OPCAB) may be associated with a significant increase in systemic blood pressure which may rarely result in aortic dissection. We evaluated whether topical application of lidocaine on the ascending aorta could reduce the rise in systemic blood pressure during side-clamping of the aorta in OPCAB.

METHODS

Forty-four patients scheduled for OPCAB were randomly allocated to receive gauze soaked with 10 ml of 4% lidocaine (n = 22) or normal saline (n = 22) on the side-clamping site of the aorta. Sodium nitroprusside (SNP) was infused as necessary to maintain the systolic blood pressure at around 100 mmHg immediately prior to and during side-clamp of the aorta. The requirement and frequency of use of SNP, as well as haemodynamic variables, were recorded serially.

RESULTS

The number of patients requiring an SNP infusion and the average amount of infused SNP were significantly less in the lidocaine group. Systolic blood pressure increased significantly during side-clamping in the control group, but not in the lidocaine group.

CONCLUSION

Topical application of lidocaine on the surface of the aorta is a simple and effective method to reduce the risk of a sudden increase in systemic blood pressure during side-clamping of the aorta.

Multivessel Revascularization on the Beating Heart by Anterolateral Left Thoracotomy

BACKGROUND

Off-pump coronary artery bypass is commonly performed through a full median sternotomy; however, the tendency to reduce surgical trauma has stimulated cardiac surgeons to use less invasive techniques for single-vessel disease. The use of thoracotomy for reoperative and valvular surgery has also been reported, but its application in primary revascularization is still uncommon. We report here a series of consecutive patients who underwent complete myocardial revascularization on the beating heart through anterolateral thoracotomy-coronary artery bypass (ALT-CAB).

METHODS

From November 2002 to July 2005, 255 patients (75.7% male, median age 57.9 +/- 10.1 years) underwent complete revascularization using the ALT-CAB approach. Eighty-two patients (32.2%) had low ejection fraction, 145 (56.9%) previous myocardial infarct, and 215 (84.3%) multivessel disease. The mean EuroSCORE (European System for Cardiac Operative Risk Evaluation) was 3.8 and the Parsonnet score was 7.8.

RESULTS

Complete revascularization was achieved in all patients (mean number of grafts 3.3 +/- 1.0). There were no conversions to cardiopulmonary bypass, and 3 patients died (1.2%). Two hundred thirty-seven patients (93.3%) were extubated in the operating room, and 164 patients (65.1%) were discharged home within 48 hours after surgery. Two patients (0.8%) experienced a stroke and 5 (2%) needed reexploration for bleeding. There was 1 perioperative myocardial infarction (0.4%), and 14 patients (5.5%) experienced postoperative atrial fibrillation. Five patients (2%) required treatment as an outpatient for superficial wound infection, 11 (4.4%) for left pleural effusion, and 11 (4.4%) for transient phrenic nerve palsy, which resolved spontaneously. Follow-up (median, 14.6 +/- 9.7 months) survival was 97.6%. One patient (0.4%), experienced a new myocardial infarction, 9 (3.6%) required new coronary angiography for recurrent of angina, and 3 of these (1.2%) underwent angioplasty.

CONCLUSIONS

Complete revascularization on the beating heart through an anterolateral thoracotomy is safe and feasible in the majority of patients requiring coronary artery surgery.

Risk and determinants of myocardial injury during off-pump coronary artery bypass grafting

Perioperative myocardial injury (PMI) after coronary revascularization (bypass surgery using cardiopulmonary bypass or percutaneous intervention) is strongly associated with future adverse events, such as death, myocardial infarction, and coronary intervention. The incidence, determinants, and prognostic significance of PMI after bypass surgery without cardiopulmonary bypass (off-pump surgery) are unknown. The study population comprised the patients who were randomized to off-pump surgery in the Octopus Study. PMI was defined by a creatine kinase isoenzyme-MB/total creatine kinase ratio of >5% during the first 48 hours, postoperatively. PMI occurred in 137 of 260 patients (52%). Using multivariate regression analysis, age, female gender, previous myocardial infarction, preoperative nitrate use, preoperative diuretic use, and number of grafts were independently associated with an increased risk of PMI during off-pump surgery. The presence of preoperative coronary collaterals showed a negative association with PMI. The occurrence of PMI had a crude odds ratio of 7.53 (95% confidence interval 1.59 to 35.63) for an adverse cardiac event at 1 year after off-pump surgery. This odds ratio changed little after adjustment for confounders (odds ratio 6.39, 95% confidence interval 1.41 to 28.93). In conclusion, more severe atherosclerotic disease and female gender were associated with an increased risk of perioperative myocardial injury during off-pump bypass surgery, although the presence of coronary collaterals appeared to be protective. Patients with perioperative myocardial injury during off-pump surgery were at a higher risk of adverse cardiac outcomes at 1 year.

Low-prime system minimizes transfusions and hemodilution in coronary bypass

Standard heart-lung machines lead to substantial hemodilution with associated impaired organ function and increased need for blood transfusions. The aim of this study was to evaluate the effect of the new PRECiSe low prime volume system on perioperative myocardial damage, hemodilution, and transfusions. In a case-matched prospective study, 40 patients undergoing coronary artery bypass surgery using PRECiSe were compared with 40 patients on a standard heart-lung machine. In the PRECiSe group, the prime volume was significantly reduced, resulting in less hemodilution and transfusion requirements during and after extracorporeal circulation: only 10% of patients needed transfusions vs. 35% in the control group, with an average transfusion need of 0.16 vs. 1.25 units. There were no significant differences in perioperative cardiac-specific enzymes. The PRECiSe system was considered safe and effective for coronary artery bypass surgery.

Expression of CD97 and Adhesion Molecules on Circulating Leukocytes in Patients Undergoing Coronary Artery Bypass Surgery

OBJECTIVE

Leukocyte activation is thought to be responsible for the adverse effects and postoperative complications following cardiopulmonary bypass (CPB). A novel cell surface molecule, CD97, is a sensitive marker of leukocyte and primary lymphocyte activation. The present study aimed to determine the activation of different leukocyte subsets by comparing the expression of CD97 and adhesion molecules (CD11, CD18) in patients receiving coronary surgery with or without CPB.

METHODS

30 patients were enrolled and scheduled for coronary bypass surgery under CPB (20 patients, group A) and with off-pump (OP) operation (10 patients, group B). Blood samples were taken before and during surgery, and over the following first week.

RESULTS

Here, we report an early decrease in CD97 expression of granulocytes (PMN) and monocytes (MC) followed by an intensive increase reaching the maximum on postoperative days 2 and 3 in patients operated with CPB. The rate of active CD97-positive lymphocytes showed a marked, gradual increase until postoperative day 3 and remained elevated up to day 7 after CPB. OP surgery resulted in moderate alteration in the presence of CD97 on PMN, MC and lymphocytes. The expression of adhesion molecules was similar to CD97 in all leukocyte subsets.

CONCLUSION

The findings about CD97 expression suggest considerable leukocyte activation following coronary bypass with CPB compared to OP surgery. The collected data show that the lymphocytes are highly activated and involved in leukocyte sequestration after CPB. Moreover, the importance of CD97 in CPB-related inflammatory response can be stated.

Composite Bilateral Internal Thoracic Artery Grafts via Standard Sternotomy for Lateral Wall Revascularization in Conscious Patients

BACKGROUND

A new technique has been developed that permits complete arterial revascularization of the lateral wall of the heart using in situ bilateral internal thoracic artery grafts in awake patients. This technique, performed without cardiopulmonary bypass or mechanical ventilation, creates the least invasive revascularization method for the lateral wall of the heart yet described.

METHODS

In 4 patients, double or triple vessel coronary artery bypass grafting was performed without general anesthesia. A high thoracic epidural anesthesia was started 1 hour before surgery. Bilateral internal thoracic arteries were harvested and all anastomoses were performed with the off-pump technique via standard median sternotomy. Circumflex branches were anastomosed with the left internal thoracic artery via a heart positioner.

RESULTS

All patients remained awake throughout the whole procedure. There was no perioperative myocardial infarction or mortality. Pneumothorax was observed in only 1 patient and did not hinder the procedure. There were no hemodynamic changes during lateral wall revascularization. Two patients required unexpected coronary endarterectomy during circumflex and right coronary artery anastomoses.

CONCLUSIONS

Complete arterial revascularization via median sternotomy using in situ bilateral internal thoracic artery grafts without general anesthesia is a feasible and safe procedure for multivessel disease. This approach allows for complete coronary artery revascularization in patients with contraindications for general anesthesia with or without cardiopulmonary bypass.

Coronary artery bypass surgery in high-risk patients

Background

In high-risk coronary artery bypass patients; off-pump versus on-pump surgical strategies still remain a matter of debate, regarding which method results in a lower incidence of perioperative mortality and morbidity. We describe our experience in the treatment of high-risk coronary artery patients and compare patients assigned to on-pump and off-pump surgery.

Methods

From March 2002 to July 2004, 86 patients with EuroSCOREs > 5 underwent myocardial revascularization with or without cardiopulmonary bypass. Patients were assigned to off-pump surgery (40) or on-pump surgery (46) based on coronary anatomy coupled with the likelihood of achieving complete revascularization.

Results

Those patients undergoing off-pump surgery had significantly poorer left ventricular function than those undergoing on-pump surgery (28.6 ± 5.8% vs. 40.5 ± 7.4%, respectively, p < 0.05) and also had higher Euroscore values (7.26 ± 1.4 vs. 12.1 ± 1.8, respectively, p < 0.05). Differences between the two groups were nonsignificant with regard to number of grafts per patient, mean duration of surgery, anesthesia and operating room time, length of stay intensive care unit (ICU) and rate of postoperative atrial fibrillation

Conclusion

Utilization of off-pump coronary artery bypass graft (CABG) does not confer significant clinical advantages in all high-risk patients. This review suggest that off-pump coronary revascularization may represent an alternative approach for treatment of patients with Euroscore ≥ 10 and left ventricular function ≤ 30%.

Bypassing the Pump

Improvements in techniques in coronary revascularization over the past decade have led to a revival of interest in off-pump coronary artery surgery. A fifth of coronary revascularization procedures are now performed off-pump. Randomized trials comparing off-pump surgery with conventional coronary artery bypass grafting using cardiopulmonary bypass (CPB) mainly included low-risk patients and were therefore underpowered to detect a difference in mortality. Current evidence, however, suggests a significant reduction in morbidity with off-pump surgery. The avoidance of CPB and the elimination of any aortic manipulation may significantly reduce the risk of stroke. Those benefits are likely to be most marked in older, sicker patients, who represent an increasing proportion of the surgical population.

Off-pump coronary artery bypass grafting does not reduce lymphocyte activation

OBJECTIVE

In this study, we test the hypothesis that off-pump coronary bypass surgery might result in less lymphocyte activation than on-pump coronary surgery. We also study the behavior of lymphocyte activation markers during and after surgery.

BACKGROUND

Coronary artery bypass surgery is known to be associated with changes of inflammatory mediators, immune function, and early phase lymphocyte activation, which could cause postoperative lymphopenia and lymphocyte unresponsiveness.

METHODS

We studied lymphocyte activation response in 28 patients randomized to off-pump (n = 13) or on-pump (n = 15) coronary artery bypass surgery. Expression of CD25, CD26, CD69, and DR on T (CD3+) and B (CD19+) lymphocytes on peripheral blood was assessed through flow cytometry.

RESULTS

The response of T lymphocytes and their activation markers, as well as B lymphocytes and their activation markers, was similar after on- and off-pump surgery. Overall, T lymphocytes decreased to the lowest level 9 h after surgery and tended to increase later. For B lymphocytes, there was early reduction with increase on the 1st postoperative day. There was early activation of CD69+ and late activation of CD25+ on T lymphocytes. For B lymphocytes, there was early activation of CD69+ and late activation of DR+.

CONCLUSIONS

(1) Compared to on-pump cardiopulmonary bypass, off-pump surgery does not reduce lymphocyte activation. (2) Coronary bypass surgery causes the early activation of lymphocytes, as evidenced by the increased expression of lymphocyte activation markers.

A New PRECiSe (Priming Reduced Extracorporeal Circulation Setup) Minimizes the Need for Blood Transfusions: First Clinical Results in Coronary Artery Bypass Grafting

Hemodilution by the crystalloid priming volume of standard heart-lung machines in cardiac surgery is associated with impaired organ function and increased blood transfusion requirements. The aim of this study was to evaluate the effect of the use of the newly developed priming reduced extracorporeal circulation setup (PRECiSe) on perioperative hemodilution and transfusion requirements. In a matched prospective study, 40 patients who underwent operations with the PRECiSe in elective primary coronary artery bypass surgery were compared with 40 patients who underwent operations with the standard heart-lung machine. A significant reduction in final priming volume resulted in a significantly reduced degree of hemodilution and transfusion requirements during and after extracorporeal circulation. In the PRECiSe group, only 10% of the patients needed transfusions during their hospital stay, whereas 35% of the patients in the control group required any transfusion (P < .05). The average transfusion per patient was 0.16 units in the PRECiSe group and 1.25 units in the control group (P < .05). The PRECiSe was demonstrated to be safe and effective in coronary artery bypass surgery with respect to transfusion requirements and hemodilution, as well as with regard to patient safety, as represented by perioperative myocardial performance.

Patient-Reported Outcome After Randomization to On-Pump Versus Off-Pump Coronary Artery Surgery

BACKGROUND

Clinical experience with off-pump coronary artery bypass surgery raises the question of a patient experienced benefit compared with on-pump surgery. This prospective and randomized study compared patient-reported outcome between surgical groups, as change scores at 3 months after surgery and longitudinally as time-averaged change from baseline through the first year after surgery.

METHODS

In all, 120 patients were randomly assigned to on- or off-pump coronary artery surgery. A questionnaire for patient self-report of angina (Canadian Cardiovascular Society scale), health status (Short Form 36, sleep and sexual difficulty), and overall quality of life (Quality of Life Scale) was administered at baseline and at 3, 6, and 12 months after surgery.

RESULTS

Patient groups were comparable with regard to age, symptoms, comorbidity, and surgical characteristics. Both groups experienced a median of two classes relief of angina at 3 months (p < 0.0005), maintained throughout follow-up. Paired t tests revealed significant improvement on all Short Form 36 subscales at 3 months after surgery, with the exception of physical role functioning in the on-pump group. No independent main effects of surgical group were observed in the between-groups covariance models. The longitudinal effect of sex was significant in four Short Form 36 subscales: physical functioning, bodily pain, and role limitation due to physical or emotional problems. Overall quality of life scores were stable in both groups.

CONCLUSIONS

Both on-pump and off-pump patients reported less angina and improved health status after surgery. There were no significant differences between surgical groups in health status or overall quality of life, neither cross-sectionally nor longitudinally.