Off-Pump versus Conventional Coronary Artery Bypass Grafting: A Meta-Analysis and Consensus Statement from the 2004 ISMICS Consensus Conference

The Impact of Robotic Versus Conventional Coronary Artery Bypass Grafting on In-Hospital Narcotic Use: A Propensity-Matched Analysis

OBJECTIVE

The aim of this study was to compare narcotic use in the perioperative hospital stay as a measure of pain in patients undergoing robotic versus conventional coronary artery bypass grafting (CABG).

METHODS

Propensity score matching of patients undergoing robotically assisted CABG and conventional CABG over a period of 5 years was performed. A retrospective chart review was performed to identify the total amount of narcotics used by both groups calculated as morphine equivalent dosing (MED).

RESULTS

From 2007 to 2012, 154 patients underwent robotic CABG, and 1660 underwent conventional CABG. Propensity matching resulted in 142 patients in each group. Patients undergoing robotic CABG received less blood transfusion, were more frequently extubated in the operating room, and had a shorter length of stay. The robotic group had a lower MED than the conventional group as defined by the primary end point [181 (11) vs 251 (8)]. If intraoperative narcotic use was eliminated, there was no difference in MED from postoperative days 0 to 3.

CONCLUSIONS

Patients undergoing robotic CABG use fewer narcotics over the first three hospital days than patients undergoing conventional CABG. The surrogate of narcotics use for postoperative pain shows that the minithoracotomy of robotic CABG may result in either less or equivalent pain than the sternotomy of conventional CABG.

The Evolution of Modern Cardiac Surgery and the Necessity to Change

This article depicts the Kit V. Arom Lecture, which was held at the 15th Annual Congress of the International Society for Minimally Invasive Cardiothoracic Surgery in Berlin, Germany. It describes the evolution of modern cardiac surgery and the necessity for cardiac surgeons to change. The article is dedicated to a pioneer in minimally invasive cardiac surgery and a good friend, Kit V. Arom, MD.

Combined Coronary Revascularization: Single-Center 10-Year Experience

OBJECTIVE

This study aimed to assess the long-term outcome of combined coronary revascularization.

METHODS

Between January 2000 and September 2010, 106 consecutive patients underwent combined coronary revascularization, either the same day or staged within 90 days. Percutaneous coronary intervention was always performed before coronary artery bypass grafting. We identified three groups as follows: one-stop combined coronary revascularization (n = 20), percutaneous coronary intervention for acute coronary syndrome before subsequent surgery (n = 39), and percutaneous coronary intervention for stable coronary artery disease before subsequent surgery (n = 47). Off-pump technique was used in all cases.

RESULTS

A total of 107 angioplasties were realized (drug-eluting stents, 21; bare metal stents, 114; balloon angioplasty, 4). Percutaneous coronary intervention was mostly performed in the right coronary artery or branches (85%). The mean (SD) number of grafts was 1.9 (0.6), among them 1.8 (0.7) with arterial grafts. A total of 87.7% of the patients underwent exclusive arterial revascularization. There was one reexploration for bleeding and no in-hospital death. Eleven patients died in the follow-up. Repeat percutaneous coronary intervention was necessary for six patients and repeat surgery for one patient. The mean (SD) follow-up was 6.1 (2.7) years. Complete follow-up was obtained in 96.2% of the patients. Freedom from ischemic events (all-cause deaths, angina, acute coronary syndrome, myocardial infarction) was 86.3% (3.7%) at 5 years and 79.7% (5.2%) at 8 years (no difference between groups). Freedom from major adverse cardiac or cerebrovascular events was 88.8% (3.4%) at 5 years and 75.7% (5.2%) at 8 years (no difference between groups).

CONCLUSIONS

Combined coronary revascularization increases the use of arterial grafts, with good long-term outcome.

ISMICS Consensus Conference and Statements of Randomized Controlled Trials of Off-Pump versus Conventional Coronary Artery Bypass Surgery

Objective

At this consensus conference, we developed evidence-informed consensus statements and recommendations on the practice of off-pump coronary artery bypass graft (OPCAB) by systematically reviewing and performing meta-analysis of the randomized controlled trials (RCTs) comparing OPCAB and conventional coronary artery bypass (CCAB).

Methods

All RCTs of OPCAB versus CCAB through April 2013 were screened, and 102 relevant RCTs (19,101 patients) were included in a systematic review and meta-analysis (15 RCTs of 9551 high-risk patients; and 87 RCTs of 9550 low-risk patients) in accordance with the Cochrane Collaboration and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology. Consensus statements for the risks and benefits of OPCAB surgery in mortality, morbidity, and resource use were developed based on best available evidence.

Results

Compared to CCAB, it is reasonable to perform OPCAB to reduce risks of stroke [class IIa, level of evidence (LOE) A], renal dysfunction/failure (class IIa, LOE A), blood transfusion (class I, LOE A), respiratory failure (class I, LOE A), atrial fibrillation (class I, LOE A), wound infection (class I, LOE A), ventilation time, and ICU and hospital length of stay (class I, LOE A). However, OPCAB may be associated with a reduced number of grafts performed (class I, LOE A) and with diminished graft patency (class IIa, LOE A, with increased coronary reintervention at 1 year and beyond (class IIa, LOE A), as well as increased mortality at a median follow-up of 5 years (class IIb, LOE A).

Conclusions

OPCAB compared with CCAB may improve outcomes in the short-term (stroke, renal dysfunction, blood transfusion, respiratory failure, atrial fibrillation, wound infection, ventilation time, and length of stay). However, over the longer-term, OPCAB may be associated with reduced graft patency, and increased risk of cardiac re-intervention and death.

Minimally Invasive Coronary Artery Bypass Grafting is Associated with Improved Clinical Outcomes

Objective

Minimally invasive coronary artery bypass grafting (MICS CABG) via left minithoracotomy is an alternative to off-pump coronary artery bypass (OPCAB) via sternotomy. Our objective was to evaluate the clinical outcomes after MICS CABG versus OPCAB.

Methods

The medical records of patients who underwent MICS CABG from December 2009 to December 2011 and OPCAB from January 2005 to April 2011 were reviewed. Patients who underwent OPCAB were matched 2:1 to patients who underwent MICS CABG by age, sex, preoperative ejection fraction, creatinine concentration, as well as history of diabetes and myocardial infarction.

Results

A total of 130 MICS CABG patients were matched with 260 OPCAB patients. Mean bypasses in the MICS CABG and OPCAB groups were 2.1 and 3.2, respectively ( P = 0.001). Extubation in the operating room (OR) occurred in 70.0% and 12.7% of patients in the MICS CABG and OPCAB groups, respectively ( P = 0.001). Mean postoperative length of stay was 4 days for the MICS CABG patients versus 5 days for the OPCAB patients ( P = 0.002) and 3.8 days versus 4.6 days for the MICS CABG patients extubated in the OR compared with those who remained intubated ( P = 0.007). There were no 30-day mortalities in the MICS CABG group and 1 in the OPCAB group (P= 0.999). Thirty-day readmissions were similar, with 5.4% and 7.4% in the MICS CABG and OPCAB groups, respectively ( P = 0.527).

Conclusions

Minimally invasive coronary artery bypass grafting is safe, and early clinical outcomes are comparable, if not superior in some respects, to OPCAB. Extubation in the OR is feasible, well tolerated, and associated with earlier discharge. Shorter hospital stays may decrease resource use and promote earlier return to activities; however, further research is needed.

The effect of combined clopidogrel and aspirin therapy after off-pump coronary surgery: a pilot study

OBJECTIVE

: The purpose of this randomized study was to evaluate the effect on graft patency by adding clopidogrel to aspirin in off-pump coronary artery bypass (OPCAB) grafting and the possible side effects of such therapy.

METHODS

: Twenty patients who underwent standard OPCAB through median sternotomy were randomized immediately after surgery in two groups. Patients in group A (n = 10) received 100 mg of aspirin starting preoperatively, continuing indefinitely. Patients in group B received 100 mg of aspirin and, in addition, 75 mg of clopidogrel starting immediately after the operation and for 3 months. Postoperative bleeding and other perioperative parameters were compared. Angiography was repeated 3 months after surgery to determine the patency and quality of grafts.

RESULTS

: Preoperative risk factors were similar in the two groups. There was no significant difference in average number of distal anastomosis (P = 0.572), operation time (P = 0.686), postoperative bleeding (P = 0.256), ventilation time (P = 0.635), and intensive care unit stay (P = 0.065). Length of stay was shorter in group B (P = 0.024). There was no postoperative complication in either groups. Eight of 27 grafts in group A and 2 of 29 grafts in group B (P = 0.037) were occluded at the time of control angiography.

CONCLUSIONS

: Early administration of a combined regimen of clopidogrel and aspirin after OPCAB grafting is not associated with increased postoperative bleeding or other major complications. Despite the small number of patients in this study and small number of examined grafts, the results suggest that the addition of clopidogrel may increase graft patency after OPCAB grafting.

Drug, Devices, Technologies, and Techniques for Blood Management in Minimally Invasive and Conventional Cardiothoracic Surgery a Consensus Statement from the International Society for Minimally Invasive Cardiothoracic Surgery (ISMICS) 2011

Objective

The objectives of this consensus conference were to evaluate the evidence for the efficacy and safety of perioperative drugs, technologies, and techniques in reducing allogeneic blood transfusion for adults undergoing cardiac surgery and to develop evidence-based recommendations for comprehensive perioperative blood management in cardiac surgery, with emphasis on minimally invasive cardiac surgery.

Methods

The consensus panel short-listed the potential topics for review from a comprehensive list of potential drugs, devices, technologies, and techniques. The process of short-listing was based on the need to prioritize and focus on the areas of highest importance to surgeons, anesthesiologists, perfusionists, hematologists, and allied health care involved in the management of patients who undergo cardiac surgery whether through the conventional or minimally invasive approach. MEDLINE, Cochrane Library, and Embase databases were searched from their date of inception to May 2011, and supplemental hand searches were also performed. Detailed methodology and search strategies are outlined in each of the subsequently published systematic reviews. In general, all relevant synonyms for drugs (antifibrinolytic, aprotinin, ∊-aminocaproic acid, tranexamic acid [TA], desmopressin, anticoagulants, heparin, antiplatelets, anti-Xa agents, adenosine diphosphate inhibitors, acetylsalicylic acid [ASA], factor VIIa [FVIIa]), technologies (cell salvage, miniaturized cardiopulmonary bypass (CPB) circuits, biocompatible circuits, ultrafiltration), and techniques (transfusion thresholds, minimally invasive cardiac or aortic surgery) were searched and combined with terms for blood, red blood cells, fresh-frozen plasma, platelets, transfusion, and allogeneic exposure. The American Heart Association/American College of Cardiology system was used to label the level of evidence and class of each recommendation.

Results and Recommendations

Database search identified more than 6900 articles, with 4423 full-text randomized controlled trials assessed for eligibility, and the final 125 systematic reviews and meta-analyses were used in the consensus conference. The results of the consensus conference, including the evidence-based statements and the recommendations, are outlined in the text, with references given for the relevant evidence that formed the basis for the statements and recommendations.

Preoperative Insertion of an Intra-Aortic Balloon Pump Improved the Prognosis of High-Risk Patients Undergoing Off-Pump Coronary Artery Bypass Grafting

This study investigated the efficacy and safety of preoperative insertion of an intra-aortic balloon pump (IABP) in high-risk coronary atherosclerotic disease patients undergoing off-pump coronary artery bypass grafting (OPCAB). A total of 232 patients were recruited to the study, of whom 107 underwent percutaneous insertion of an IABP prior to OPCAB. The remaining 125 patients underwent OPCAB alone. Pre-, peri- and postoperative parameters were compared between the two groups. Preoperative insertion of an IABP was associated with a shorter stay in intensive care, decreased incidence of postoperative dialysis and acute heart failure, and a reduction in postoperative mortality compared with OPCAB alone. There were no between-group differences in terms of haematocrit level, number of distal anastomoses, volume of postoperative drainage or incidence of reoperation for bleeding and postoperative stroke/cerebrovascular accident. In conclusion, preoperative insertion of an IABP improved the prognosis of high-risk CAD patients undergoing OPCAB.

Minimally Invasive versus Open Mitral Valve Surgery a Consensus Statement of the International Society of Minimally Invasive Coronary Surgery (ISMICS) 2010

Objective

The purpose of this consensus conference was to deliberate the evidence regarding whether minimally invasive mitral valve surgery via thoracotomy improves clinical and resource outcomes compared with conventional open mitral valve surgery via median sternotomy in adults who require surgical intervention for mitral valve disease.

Methods

Before the consensus conference, the consensus panel reviewed the best available evidence up to March 2010, whereby systematic reviews, randomized trials, and nonrandomized trials were considered in descending order of validity and importance. The accompanying meta-analysis article in this issue of the Journal provides the systematic review of the evidence. Based on this systematic review, evidence-based statements were created for pre-specified clinical questions, and consensus processes were used to derive recommendations. The American Heart Association/American College of Cardiology system was used to label the level of evidence and class of each recommendation.

Results and Conclusions

Considering the underlying level of evidence, and notwithstanding the limitations of the evidence base (retrospective studies with important differences in baseline patient characteristics, which may produce bias in results of the evidence syntheses), the consensus panel provided the following evidence-based statements and overall recommendation: In patients with mitral valve disease, minimally invasive surgery may be an alternative to conventional mitral valve surgery (Class IIb), given that there was comparable short-term and long-term mortality (level B), comparable in-hospital morbidity (renal, pulmonary, cardiac complications, pain perception, and readmissions) (level B), reduced sternal complications, transfusions, postoperative atrial fibrillation, duration of ventilation, and intensive care unit and hospital length of stay (level B). However, this should be considered against the increased risk of stroke (2.1% vs 1.2%) (level B), aortic dissection (0.2% vs 0%) (level B), phrenic nerve palsy (3% vs 0%) (level B), groin infections/complications (2% vs 0%) (level B), and, prolonged cross-clamp time, cardiopulmonary bypass time, and procedure time (level B). The available evidence consists almost entirely of observational studies and must not be considered definitive until future adequately controlled randomized trials further address the risk of stroke, aortic complications, phrenic nerve complications, pain, long-term survival, need for reintervention, quality of life, and cost-effectiveness.

Selective beta-1 receptor blockade further reduces the mechanically stabilized target coronary artery motion during beating heart surgery

OBJECTIVE

Adequate stabilization of anastomosis sites during off-pump coronary artery bypass is essential to obtain excellent graft patency. We examined the effect of beta-1 adrenergic receptor blockade on the target coronary artery motion by three-dimensional (3D) digital motion capture and reconstruction technology.

METHODS

Eight pigs underwent a sternotomy. Reflection markers were attached to the surface coronary arteries, followed by a mechanical stabilizer application. Two high-speed digital cameras captured two-dimensional (2D) motion of the markers from different angles. These 2D data were reconstructed into 3D data points, representing the motion of each coronary artery. Landiolol hydrochloride, a novel selective beta-1 receptor blocker, was infused intravenously after acquisition of control data.

RESULTS

Beta-1 receptor blockade decreased heart rate (105 ± 16 vs. 90 ± 9 beat/min; P = 0.007) without decreasing arterial blood pressure. The 3D distance moved (millimeter) during one cardiac cycle was significantly reduced on the left anterior descending (9.6 ± 2.8 vs. 6.6 ± 1.9 mm; P = 0.003), left circumflex (10.5 ± 6.3 vs. 6.4 ± 2.6 mm; P = 0.038), and right coronary (8.3 ± 3.6 vs. 6.5 ± 2.1 mm; P = 0.028) arteries. Reduction in the maximal velocity, maximal acceleration, and maximal deceleration of the anastomosis site in all coronary arteries was also found in a quantitative fashion.

CONCLUSIONS

Selective beta-1 receptor blockade significantly reduces the 3D motion at anastomosis sites on the beating heart, with stable systemic blood pressure. Further quantitative investigations of pharmacological stabilization are warranted to achieve better outcome of the patients undergoing off-pump coronary artery bypass surgery.

Off-pump Coronary Bypass Surgery in Patients with Low Ejection Fraction

Objective

Long-term survival after off-pump surgery in patients with low ejection fraction was investigated.

Methods

Three hundred forty-six patients with ejection fraction 30% or less with isolated off-pump coronary artery bypass surgery (OPCAB) were compared with a propensity matched historical group operated on-pump (ONCAB) and with data from literature after percutaneous coronary intervention and OPCAB surgery.

Results

The lower invasiveness of OPCAB contributed to a significantly better 30-day survival, shorter postoperative length of stay, and fewer in-hospital complications. Incomplete revascularization of the posterior and lateral territories of the heart correlated with higher 1-year mortality. The probability of survival for 8 years after OPCAB was 50.1% (n = 76) versus 49.7% (n = 82) for ONCAB without comparable data from literature for OPCAB or percutaneous coronary intervention in these high-risk patients.

Conclusions

OPCAB surgery in patients with low ejection fraction is a viable alternative but so far without demonstrable long-term survival advantage to ONCAB.

Impact of Previous PCI on Hospital Mortality After Off-Pump Coronary Artery Bypass Grafting in Diabetic Patients With Multivessel Disease

OBJECTIVE

: Because percutaneous coronary intervention (PCI) has been performed excessively, many patients initially managed with PCI are being referred for coronary artery bypass grafting (CABG). The purpose of this study was to assess the impact of previous PCI on surgical mortality after off-pump CABG in diabetic patients with multivessel disease.

METHODS

: Between January 2002 and April 2008, 595 consecutive patients (99.8% off-pump) had isolated CABG by one single surgeon. Of these, 274 patients with diabetes mellitus and multivessel disease were retrospectively analyzed. Patients with previous PCI (n = 79) were compared with patients with no previous PCI (n = 196), and risk-adjusted impact of previous PCI on surgical mortality after CABG was determined using multivariate and propensity score analyses.

RESULTS

: All patients underwent off-pump CABG without conversion to cardiopulmonary bypass during operation. Patients with previous PCI had a significantly higher prevalence of history of myocardial infarction, renal dysfunction, and hemodialysis. Rates of surgical mortality were higher in patients with previous PCI (7.6% versus 1.0%, P = 0.008). After multivariate logistic regression analysis including all potential univariate predictors, previous PCI remained a strong predictor of surgical mortality [odds ratio (OR), 6.9; 95% confidence interval (CI), 1.2 to 42.1; P = 0.035]. After matching and regression adjustment by propensity score, the impact of previous PCI on surgical mortality was similar in direction (matching OR, 6.5; 95% CI, 0.8 to 55.0; P = 0.088; regression adjustment OR, 6.3; 95% CI, 1.2 to 33.6; P = 0.031).

CONCLUSIONS

: Previous PCI increases the risk of surgical mortality after off-pump CABG in diabetic patients with multivessel disease.

Inflammatory and Hemostatic Activation in Patients Undergoing Off-Pump Coronary Artery Bypass Grafting

To characterize hemostatic differences imposed by 2 common cardiac surgeries, the authors studied patients undergoing coronary artery revascularization by off-pump (n = 13) or cardiopulmonary bypass on-pump (n = 26) technique. Blood samples collected to 4 days post-surgery were evaluated by flow cytometry and enzyme-linked immunosorbent assay. A significant inflammatory response occurred in both the groups after surgery shown by increased interleukin cytokines and C-reactive protein; however, levels peaked lower and hours later in the off-pump group. Platelets (P-selectin; platelet-leukocyte complexes) and leukocytes (CD11b) were activated only in on-pump patients. Thrombin generation was enhanced in both groups after surgery. Only in the on-pump patients, the thrombin-antithrombin complex, pro-thrombin fragment 1.2, and thrombomodulin (vascular integrity) decreased intraoperatively. Tissue plasminogen activator and plasminogen activator inhibitor-1 were greater in the on-pump patients. Off-pump surgery may place patients at higher risk of postoperative hypercoagulability because of normal platelet function, intraoperative thrombin generation, less fibrinolytic activity, and lack of vascular protection.

Can surgeons do complete revascularization in diabetic patients using the off-pump technique?

BACKGROUND

: The arguments are discussed as to whether or not to proceed with multivessel percutaneous coronary intervention, with or without a drug-eluting stent, in patients with diabetes mellitus (DM), including (1) surgeons unable to complete revascularization because of smaller native arteries; and (2) diabetic patients being sicker and having higher operative mortality rates than nondiabetic patients (non-DM), particularly with the conventional coronary artery bypass surgery (on-pump) technique. To support or dispute the claims, a retrospective review of 480 consecutive patients at a single institution (195 DM and 285 non-DM) was carried out. Observations were made to see whether diabetes is a predictor of poor outcomes.

MATERIALS AND METHODS

: The preoperative comorbidity, intraoperative measurement of the size of the artery at the site of anastomosis with different gauged probes, and the number of grafts per patient were recorded. Intraoperative and postoperative variables between two groups were compared. The observed number of grafts (O) after surgery was compared with the number of grafts predicted (P) before surgery. The O/P ratio or "completion index" of ≥1 signifies complete revascularization. Logistic regression analysis was used to test the possibility that diabetes is a predictor of poor outcomes.

RESULTS

: Diabetic patients were older, with more comorbidity (congestive heart failure, peripheral vascular diseases, dialysis-dependent). The number of grafts per patient was 4.2 ± 1.3 (DM) and 4.2 ± 1.3 (non-DM). The size of 742 DM and 949 non-DM arteries were gauged. There was no statistical difference in size between DM and non-DM (in millimeters) at each artery. All ratios ranged from 0.9 to 1.2, indicating similarity between DM and non-DM. The only significant risk factor for operative death was low left ventricular ejection fraction (P = 0.001).

CONCLUSIONS

: Patients with DM were sicker but tolerated off-pump coronary artery bypass grafting as well as non-DM patients. The number of grafts per patient and O/P ratio signify the ability to perform complete revascularization. We are able to bypass the small target vessels, as anticipated. Diabetes is not a predictor of the outcomes.