ACCF/AHA Practice Guideline 2011 ACCF/AHA Guideline for Coronary Artery Bypass Graft Surgery A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines Developed in Collaboration With the American Association for Thoracic Surgery, Society of Cardiovascular Anesthesiologists, and Society of Thoracic Surgeons WRITING COMMITTEE MEMBERS* L. David Hillis, MD, FACC, Chair ; Peter K. Smith, MD, FACC, Vice Chair* ; Jeffrey L. Anderson, MD, FACC, FAHA* ; John A. Bittl, MD, FACC ; Charles R. Bridges, MD, SCD, FACC, FAHA* ; John G. Byrne, MD, FACC ; Joaquin E. Cigarroa, MD, FACC ; Verdi J. DiSesa, MD, FACC ; Loren F. Hiratzka, MD, FACC, FAHA ; Adolph M. Hutter, Jr, MD, MACC, FAHA ; Michael E. Jessen, MD, FACC* ; Ellen C. Keeley, MD, MS ; Stephen J. Lahey, MD ; Richard A. Lange, MD, FACC, FAHA ; Martin J. London, MD ; Michael J. Mack, MD, FACC* ; Manesh R. Patel, MD, FACC ; John D. Puskas, MD, FACC* ; Joseph F. Sabik, MD, FACC*#; Ola Selnes, PhD ; David M. Shahian, MD, FACC, FAHA**; Jeffrey C. Trost, MD, FACC* ; Michael D. Winniford, MD, FACC ACCF/AHA TASK FORCE MEMBERS Alice K. Jacobs, MD, FACC, FAHA, Chair; Jeffrey L. Anderson, MD, FACC, FAHA, Chair-Elect; Nancy Albert, PhD, CCNS, CCRN, FAHA; Mark A. Creager, MD, FACC, FAHA; Steven M. Ettinger, MD, FACC; Robert A. Guyton, MD, FACC; Jonathan L. Halperin, MD, FACC, FAHA; Judith S. Hochman, MD, FACC, FAHA; Frederick G. Kushner, MD, FACC, FAHA; E. Magnus Ohman, MD, FACC; William Stevenson, MD, FACC, FAHA; Clyde W. Yancy, MD, FACC, FAHA *Writing committee members are required to recuse themselves from voting on sections to which their specific relationship with industry and other entities may apply; see Appendix 1 for recusal information. ACCF/AHA Representative. ACCF/AHA Task Force on Practice Guidelines Liaison. Joint Revascularization Section Author. Society of Cardiovascular Anesthesiologists Representative. American Association for Thoracic Surgery Representative. #Society of Thoracic Surgeons Representative. **ACCF/AHA Task Force on Performance Measures Liaison. This document was approved by the American Heart Association Science Advisory and Coordinating Committee in July 2011, and by the American College of Cardiology Foundation Board of Trustees in July 2011. The American Heart Association requests that this document be cited as follows: Hillis LD, Smith PK, Anderson JL, Bittl JA, Bridges CR, Byrne JG, Cigarroa JE, DiSesa VJ, Hiratzka LF, Hutter AM Jr, Jessen ME, Keeley EC, Lahey SJ, Lange RA, London MJ, Mack MJ, Patel MR, Puskas JD, Sabik JF, Selnes O, Shahian DM, Trost JC, Winniford MD. 2011 ACCF/AHA guideline for coronary artery bypass graft surgery: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation. 2011;124:e652 e735. This article has been copublished in the Journal of the American College of Cardiology. Copies: This document is available on the World Wide Web sites of the American College of Cardiology (www.cardiosource.org) and the American Heart Association (my.americanheart.org). A copy of the document is available at http://my.americanheart.org/statements by selecting either the By Topic link or the By Publication Date link. To purchase additional reprints, call 843-216-2533 or e-mail kelle.ramsay@wolterskluwer.com. Expert peer review of AHA Scientific Statements is conducted at the AHA National Center. For more on AHA statements and guidelines development, visit http://my.americanheart.org/statements and select the Policies and Development link. Permissions: Multiple copies, modification, alteration, enhancement, and/or distribution of this document are not permitted without the express permission of the American Heart Association. Instructions for obtaining permission are located at http://www.heart.org/HEARTORG/General/Copyright- Permission-Guidelines_UCM_300404_Article.jsp. A link to the Copyright Permissions Request Form appears on the right side of the page. 2011 by the American College of Cardiology Foundation and the American Heart Association, Inc. Circulation is available at http://circ.ahajournals.org DOI: 10.1161/CIR.0b013e31823c074e Table of Contents Preamble e654 1. Introduction e656 1.1. Methodology and Evidence Review e656 1.2. Organization of the Writing Committee e657 1.3. Document Review and Approval e657 2. Procedural Considerations e657 2.1. Intraoperative Considerations e657 2.1.1. Anesthetic Considerations: Recommendations e657 2.1.2. Use of CPB e659 2.1.3. Off-Pump CABG Versus Traditional On-Pump CABG e659 2.1.4. Bypass Graft Conduit: Recommendations e660 2.1.4.1. Saphenous Vein Grafts e661 2.1.4.2. Internal Mammary Arteries e661 2.1.4.3. Radial, Gastroepiploic, and Inferior Epigastric Arteries e661 2.1.5. Incisions for Cardiac Access e661 2.1.6. Anastomotic Techniques e662 2.1.7. Intraoperative TEE: Recommendations e662 2.1.8. Preconditioning/Management of Myocardial Ischemia: Recommendations e663 2.2. Clinical Subsets e664 2.2.1. CABG in Patients With Acute MI: Recommendations e664 2.2.2. Life-Threatening Ventricular Arrhythmias: Recommendations e666 2.2.3. Emergency CABG After Failed PCI: Recommendations e666 2.2.4. CABG in Association With Other Cardiac Procedures: Recommendations e667 3. CAD Revascularization e667 3.1. Heart Team Approach to Revascularization Decisions: Recommendations e668 3.2. Revascularization to Improve Survival: Recommendations e668 3.3. Revascularization to Improve Symptoms: Recommendations e671 3.4. CABG Versus Contemporaneous Medical Therapy e671 3.5. PCI Versus Medical Therapy e671 3.6. CABG Versus PCI e672 3.6.1. CABG Versus Balloon Angioplasty or BMS e672 3.6.2. CABG Versus DES e672 3.7. Left Main CAD e673 3.7.1. CABG or PCI Versus Medical Therapy for Left Main CAD e673 3.7.2. Studies Comparing PCI Versus CABG for Left Main CAD e673 3.7.3. Revascularization Considerations for Left Main CAD e674 3.8. Proximal LAD Artery Disease e674 3.9. Clinical Factors That May Influence the Choice of Revascularization e674 3.9.1. Diabetes Mellitus e674 3.9.2. Chronic Kidney Disease e675 3.9.3. Completeness of Revascularization e675 3.9.4. LV Systolic Dysfunction e675 3.9.5. Previous CABG e675 3.9.6. Unstable Angina/Non ST-Elevation Myocardial Infarction e676 3.9.7. DAPT Compliance and Stent Thrombosis: Recommendation e676 3.10. TMR as an Adjunct to CABG e676 3.11. Hybrid Coronary Revascularization: Recommendations e676 4. Perioperative Management e677 4.1. Preoperative Antiplatelet Therapy: Recommendations e677 4.2. Postoperative Antiplatelet Therapy: Recommendations e677 4.3. Management of Hyperlipidemia: Recommendations e678 4.3.1. Timing of Statin Use and CABG Outcomes e679 4.3.1.1. Potential Adverse Effects of Perioperative Statin Therapy e679 4.4. Hormonal Manipulation: Recommendations e679 4.4.1. Glucose Control e679 4.4.2. Postmenopausal Hormone Therapy e680 4.4.3. CABG in Patients With Hypothyroidism e680 4.5. Perioperative Beta Blockers: Recommendations e680 4.6. ACE Inhibitors/ARBs: Recommendations e681 4.7. Smoking Cessation: Recommendations e682 4.8. Emotional Dysfunction and Psychosocial Considerations: Recommendation e683 4.8.1. Effects of Mood Disturbance and Anxiety on CABG Outcomes e683 4.8.2. Interventions to Treat Depression in CABG Patients e683 4.9. Cardiac Rehabilitation: Recommendation e683 4.10. Perioperative Monitoring e684 Hillis et al 2011 ACCF/AHA CABG Guideline e653 4.10.1. Electrocardiographic Monitoring: Recommendations e684 4.10.2. Pulmonary Artery Catheterization: Recommendations e684 4.10.3. Central Nervous System Monitoring: Recommendations e684 5. CABG-Associated Morbidity and Mortality: Occurrence and Prevention e685 5.1. Public Reporting of Cardiac Surgery Outcomes: Recommendation e685 5.1.1. Use of Outcomes or Volume as CABG Quality Measures: Recommendations e686 5.2. Adverse Events e687 5.2.1. Adverse Cerebral Outcomes e687 5.2.1.1. Stroke e687 5.2.1.1.1. Use of Epiaortic Ultra- sound Imaging to Reduce Stroke Rates: Recom- mendation e687 5.2.1.1.2. The Role of Preoperative Carotid Artery Noninva- sive Screening in CABG Patients: Recommenda- tions e687 5.2.1.2. Delirium e689 5.2.1.3. Postoperative Cognitive Impairment e689 5.2.2. Mediastinitis/Perioperative Infection: Recommendations e689 5.2.3. Renal Dysfunction: Recommendations e691 5.2.4. Perioperative Myocardial Dysfunction: Recommendations e692 Recommendation e692 5.2.5. Perioperative Dysrhythmias: Recommendations e692 5.2.6. Perioperative Bleeding/Transfusion: Recommendations e693 6. Specific Patient Subsets e694 6.1. Elderly e694 6.2. Women e694 6.3. Patients With Diabetes Mellitus e695 6.4. Anomalous Coronary Arteries: Recommendations e696 6.5. Patients With Chronic Obstructive Pulmonary Disease/Respiratory Insufficiency: Recommendations e696 6.6. Patients With End-Stage Renal Disease on Dialysis: Recommendations e697 6.7. Patients With Concomitant Valvular Disease: Recommendations e697 6.8. Patients With Previous Cardiac Surgery: Recommendation e697 6.8.1. Indications for Repeat CABG e697 6.8.2. Operative Risk e698 6.8.3. Long-Term Outcomes e698 6.9. Patients With Previous Stroke e698 6.10. Patients With PAD e698 7. Economic Issues e698 7.1. Cost-Effectiveness of CABG and PCI e698 7.1.1. Cost-Effectiveness of CABG Versus PCI e699 7.1.2. CABG Versus PCI With DES e699 8. Future Research Directions e699 8.1. Hybrid CABG/PCI e700 8.2. Protein and Gene Therapy e700 8.3. Teaching CABG to the Next Generation: Use of Surgical Simulators e700 References e701 Appendix 1. Author Relationships With Industry and Other Entities (Relevant) e731 Appendix 2. Reviewer Relationships With Industry and Other Entitites (Relevant) e733 Appendix 3. Abbreviation List e735 Preamble The medical profession should play a central role in evaluating the evidence related to drugs, devices, and procedures for the detection, management, and prevention of disease. When prop- erly applied, expert analysis of available data on the benefits and risks of these therapies and procedures can improve the quality of care, optimize patient outcomes, and favorably affect costs by focusing resources on the most effective strategies. An organized and directed approach to a thorough review of evidence has resulted in the production of clinical practice guidelines that assist physicians in selecting the best management strategy for an individual patient. Moreover, clinical practice guidelines can provide a foundation for other applications, such as performance measures, appropriate use criteria, and both quality improvement and clinical decision support tools. The American College of Cardiology Foundation (ACCF) and the American Heart Association (AHA) have jointly produced guidelines in the area of cardiovascular disease since 1980. The ACCF/AHA Task Force on Practice Guide- lines (Task Force), charged with developing, updating, and revising practice guidelines for cardiovascular diseases and procedures, directs and oversees this effort. Writing commit- tees are charged with regularly reviewing and evaluating all available evidence to develop balanced, patientcentric recom- mendations for clinical practice. Experts in the subject under consideration are selected by the ACCF and AHA to examine subject-specific data and write guidelines in partnership with representatives from other medical organizations and specialty groups. Writing committees are asked to perform a formal literature review; weigh the strength of evidence for or against particular tests, treatments, or procedures; and include estimates of expected outcomes where such data exist. Patient-specific modifiers, comorbidities, and issues of patient preference that may influence the choice of tests or therapies are considered. When available, information from studies on cost is consid- ered, but data on efficacy and outcomes constitute the primary basis for the recommendations contained herein. In analyzing the data and developing recommendations and supporting text, the writing committee uses evidence-based methodologies developed by the Task Force.1 The Class of Recommendation (COR) is an estimate of the size of the treatment effect considering risks versus benefits in addition to evidence and/or agreement that a given treatment or procedure is or is not useful/effective or in some situations may cause harm. The Level of Evidence (LOE) is an estimate of the certainty or precision of the treatment effect. The writing committee reviews and ranks evidence supporting each recommendation with the weight of evidence ranked as LOE A, B, or C according to specific definitions that are included in Table 1. Studies are identified as observational, retrospective, prospective, or randomized where appropriate. For certain conditions for which inadequate data are avail- able, recommendations are based on expert consensus and clinical experience and are ranked as LOE C. When recommen- dations at LOE C are supported by historical clinical data, appropriate references (including clinical reviews) are cited if available. For issues for which sparse data are available, a survey of current practice among the clinicians on the writing commit- tee is the basis for LOE C recommendations, and no references are cited. The schema for COR and LOE is summarized in Table Table 1. Applying Classification of Recommendations and Level of Evidence A recommendation with Level of Evidence B or C does not imply that the recommendation is weak. Many important clinical questions addressed in the guidelines do not lend themselves to clinical trials. Although randomized trials are unavailable, there may be a very clear clinical consensus that a particular test or therapy is useful or effective. *Data available from clinical trials or registries about the usefulness/efficacy in different subpopulations, such as sex, age, history of prior myocardial infarction, history of heart failure, and prior aspirin use. For comparative effectiveness recommendations (Class I and IIa; Level of Evidence A and B only), studies that support the use of comparator verbs should involve direct omparisons of the treatments or strategies being evaluated. Hillis et al 2011 ACCF/AHA CABG Guideline e655 1, which also provides suggested phrases for writing recommen- dations within each COR. A new addition to this methodology is separation of the Class III recommendations to delineate if the recommendation is determined to be of no benefit or is associated with harm to the patient. In addition, in view of the increasing number of comparative effectiveness studies, com- parator verbs and suggested phrases for writing recommenda- tions for the comparative effectiveness of one treatment or strategy versus another have been added for COR I and IIa, LOE A or B only. In view of the advances in medical therapy across the spectrum of cardiovascular diseases, the Task Force has designated the term guideline-directed medical therapy (GDMT) to represent optimal medical therapy as defined by ACCF/AHA guideline recommended therapies (primarily Class I). This new term, GDMT, will be used herein and throughout all future guidelines. Because the ACCF/AHA practice guidelines address pa- tient populations (and healthcare providers) residing in North America, drugs that are not currently available in North America are discussed in the text without a specific COR. For studies performed in large numbers of subjects outside North America, each writing committee reviews the potential influ- ence of different practice patterns and patient populations on the treatment effect and relevance to the ACCF/AHA target population to determine whether the findings should inform a specific recommendation. The ACCF/AHA practice guidelines are intended to assist healthcare providers in clinical decision making by describing a range of generally acceptable approaches to the diagnosis, management, and prevention of specific diseases or conditions. The guidelines attempt to define practices that meet the needs of most patients in most circumstances. The ultimate judgment regarding the care of a particular patient must be made by the healthcare provider and patient in light of all the circumstances presented by that patient. As a result, situations may arise for which deviations from these guidelines may be appropriate. Clinical decision making should involve consideration of the quality and availability of expertise in the area where care is provided. When these guidelines are used as the basis for regulatory or payer decisions, the goal should be improvement in quality of care. The Task Force recognizes that situations arise in which additional data are needed to inform patient care more effectively; these areas will be identified within each respective guideline when appropriate. Prescribed courses of treatment in accordance with these recommendations are effective only if followed. Because lack of patient understanding and adherence may adversely affect outcomes, physicians and other healthcare providers should make every effort to engage the patient s active participation in prescribed medical regimens and lifestyles. In addition, patients should be informed of the risks, benefits, and alternatives to a particular treatment and be involved in shared decision making whenever feasible, particularly for COR IIa and IIb, where the benefit-to-risk ratio may be lower. The Task Force makes every effort to avoid actual, potential, or perceived conflicts of interest that may arise as a result of industry relationships or personal interests among the members of the writing committee. All writing committee members and peer reviewers of the guideline are required to disclose all such current relationships, as well as those existing 12 months previously. In December 2009, the ACCF and AHA implemented a new policy for relationships with industry and other entities (RWI) that requires the writing committee chair plus a minimum of 50% of the writing committee to have no relevant RWI (Appendix 1 for the ACCF/AHA definition of relevance). These statements are reviewed by the Task Force and all members during each conference call and meeting of the writing committee and are updated as changes occur. All guideline recommendations require a confidential vote by the writing committee and must be approved by a consensus of the voting members. Members are not permitted to write, and must recuse themselves from voting on, any recommendation or section to which their RWI apply. Members who recused themselves from voting are indicated in the list of writing committee members, and section recusals are noted in Appendix 1. Authors and peer reviewers RWI pertinent to this guideline are disclosed in Appendixes 1 and 2, respectively. Additionally, to ensure complete transparency, writing committee members comprehen- sive disclosure information including RWI not pertinent to this document is available as an online supplement. Comprehensive disclosure information for the Task Force is also available online at www.cardiosource.org/ACC/About-ACC/Leadership/Guidelines- and-Documents-Task-Forces.aspx. The work of the writing com- mittee was supported exclusively by the ACCF and AHA without commercial support. Writing committee members volunteered their time for this activity. In an effort to maintain relevance at the point of care for practicing physicians, the Task Force continues to oversee an ongoing process improvement initiative. As a result, in response to pilot projects, evidence tables (with references linked to abstracts in PubMed) have been added. In April 2011, the Institute of Medicine released 2 reports: Finding What Works in Health Care: Standards for Systematic Reviews and Clinical Practice Guidelines We Can Trust.2,3 It is noteworthy that the ACCF/AHA guidelines are cited as being compliant with many of the proposed standards. A thorough review of these reports and of our current methodology is under way, with further enhancements anticipated. The recommendations in this guideline are considered current until they are superseded by a focused update or the full-text guideline is revised. Guidelines are official policy of both the ACCF and AHA. Alice K. Jacobs, MD, FACC, FAHA Chair ACCF/AHA Task Force on Practice Guidelines 1.1. Methodology and Evidence Review Whenever possible, the recommendations listed in this docu- ment are evidence based. Articles reviewed in this guideline revision covered evidence from the past 10 years through January 2011, as well as selected other references through April 2011. Searches were limited to studies, reviews, and other evidence conducted in human subjects that were published in English. Key search words included but were not limited to the following: analgesia, anastomotic techniques, antiplatelet agents, automated proximal clampless anastomosis device, asymptomatic ischemia, Cardica C-port, cost effectiveness, de- pressed left ventricular (LV) function, distal anastomotic tech- niques, direct proximal anastomosis on aorta, distal anastomotic devices, emergency coronary artery bypass graft (CABG) and ST-elevation myocardial infarction (STEMI), heart failure, in- terrupted sutures, LV systolic dysfunction, magnetic connectors, PAS-Port automated proximal clampless anastomotic device, patency, proximal connectors, renal disease, sequential anasto- mosis, sternotomy, symmetry connector, symptomatic ischemia, proximal connectors, sequential anastomosis, T grafts, thoracot- omy, U-clips, Ventrica Magnetic Vascular Port system, Y grafts. Additionally, the committee reviewed documents related to the subject matter previously published by the ACCF and AHA. References selected and published in this document are repre- sentative but not all-inclusive. To provide clinicians with a comprehensive set of data, whenever deemed appropriate or when published, the absolute risk difference and number needed to treat or harm are provided in the guideline, along with confidence interval (CI) and data related to the relative treatment effects such as odds ratio (OR), relative risk (RR), hazard ratio (HR), or incidence rate ratio. The focus of these guidelines is the safe, appropriate, and efficacious performance of CABG. 1.2. Organization of the Writing Committee The committee was composed of acknowledged experts in CABG, interventional cardiology, general cardiology, and cardiovascular anesthesiology. The committee included rep- resentatives from the ACCF, AHA, American Association for Thoracic Surgery, Society of Cardiovascular Anesthesiolo- gists, and Society of Thoracic Surgeons (STS). 1.3. Document Review and Approval This document was reviewed by 2 official reviewers, each nominated by both the ACCF and the AHA, as well as 1 reviewer each from the American Association for Thoracic Surgery, Society of Cardiovascular Anesthesiologists, and STS, as well as members from the ACCF/AHA Task Force on Data Standards, ACCF/AHA Task Force on Performance Measures, ACCF Surgeons Scientific Council, ACCF Inter- ventional Scientific Council, and Southern Thoracic Surgical Association. All information on reviewers RWI was distrib- uted to the writing committee and is published in this document (Appendix 2). This document was approved for publication by the gov- erning bodies of the ACCF and the AHA and endorsed by the American Association for Thoracic Surgery, Society of Car- diovascular Anesthesiologists, and STS. 2. Procedural Considerations 2.1. Intraoperative Considerations 2.1.1. Anesthetic Considerations: Recommendations Class I 1. Anesthetic management directed toward early postop- erative extubation and accelerated recovery of low- to medium-risk patients undergoing uncomplicated CABG is recommended.4 6 (Level of Evidence: B) 2. Multidisciplinary efforts are indicated to ensure an optimal level of analgesia and patient comfort throughout the perioperative period.7 11 (Level of Evidence: B) 3. Efforts are recommended to improve interdisciplin- ary communication and patient safety in the periop- erative environment (eg, formalized checklist-guided multidisciplinary communication).12 15 (Level of Ev- idence: B) 4. A fellowship-trained cardiac anesthesiologist (or ex- perienced board-certified practitioner) credentialed in the use of perioperative transesophageal echocar- diography (TEE) is recommended to provide or supervise anesthetic care of patients who are consid- ered to be at high risk.16 18 (Level of Evidence: C) Class IIa 1. Volatile anesthetic-based regimens can be useful in facilitating early extubation and reducing patient recall.5,19 21 (Level of Evidence: A) Class IIb 1. The effectiveness of high thoracic epidural anesthe- sia/analgesia for routine analgesic use is uncer- tain.22 25 (Level of Evidence: B) Class III: HARM 1. Cyclooxygenase-2 inhibitors are not recommended for pain relief in the postoperative period after CABG.26,27 (Level of Evidence: B) 2. Routine use of early extubation strategies in facilities with limited backup for airway emergencies or advanced respiratory support is potentially harmful. (Level of Evidence: C) See Online Data Supplement 1 for additional data on anes- thetic considerations. Anesthetic management of the CABG patient mandates a favorable balance of myocardial oxygen supply and demand to prevent or minimize myocardial injury (Section 2.1.8). Histori- cally, the popularity of several anesthetic techniques for CABG has varied on the basis of their known or potential adverse cardiovascular effects (eg, cardiovascular depression with high doses of volatile anesthesia, lack of such depression with high-dose opioids, or coronary vasodilation and concern for a steal phenomenon with isoflurane) as well as concerns about interactions with preoperative medications (eg, cardiovascular depression with beta blockers or hypotension with angiotensin- converting enzyme [ACE] inhibitors and angiotensin-receptor blockers [ARBs]28 30) (Sections 2.1.8 and 4.5). Independent of these concerns, efforts to improve outcomes and to reduce costs have led to shorter periods of postoperative mechanical ventila- tion and even, in some patients, to prompt extubation in the operating room ( accelerated recovery protocols or fast-track High-dose opioid anesthesia with benzodiazepine supple- mentation was used commonly in CABG patients in the United States in the 1970s and 1980s. Subsequently, it became clear that volatile anesthetics are protective in the setting of myocardial ischemia and reperfusion, and this, in Hillis et al 2011 ACCF/AHA CABG Guideline e657 combination with a shift to accelerated recovery or fast- track strategies, led to their ubiquitous use. As a result, opioids have been relegated to an adjuvant role.32,33 Despite their widespread use, volatile anesthetics have not been shown to provide a mortality rate advantage when compared with other intravenous regimens (Section 2.1.8). Optimal anesthesia care in CABG patients should include 1) a careful preoperative evaluation and treatment of modifi- able risk factors; 2) proper handling of all medications given of central venous access and careful cardiovascular monitor- ing; 4) induction of a state of unconsciousness, analgesia, and immobility; and 5) a smooth transition to the early postoper- ative period, with a goal of early extubation, patient mobili- zation, and hospital discharge. Attention should be directed at preventing or minimizing adverse hemodynamic and hor- monal alterations that may induce myocardial ischemia or exert a deleterious effect on myocardial metabolism (as may occur during cardiopulmonary bypass [CPB]) (Section 2.1.8). This requires close interaction between the anesthesiologist and surgeon, particularly when manipulation of the heart or great vessels is likely to induce hemodynamic instability. During on-pump CABG, particular care is required during vascular cannulation and weaning from CPB; with off-pump CABG, the hemodynamic alterations often caused by dis- placement or verticalization of the heart and application of stabilizer devices on the epicardium, with resultant changes in heart rate, cardiac output, and systemic vascular resistance, should be monitored carefully and managed appropriately. In the United States, nearly all patients undergoing CABG receive general anesthesia with endotracheal intubation uti- lizing volatile halogenated general anesthetics with opioid supplementation. Intravenous benzodiazepines often are given as premedication or for induction of anesthesia, along with other agents such as propofol or etomidate. Nondepo- larizing neuromuscular-blocking agents, particularly nonva- golytic agents with intermediate duration of action, are preferred to the longer-acting agent, pancuronium. Use of the latter is associated with higher intraoperative heart rates and a higher incidence of residual neuromuscular depression in the early postoperative period, with a resultant delay in extubation.23,34 In addition, low concentrations of volatile anesthetic usually are administered via the venous oxygenator during CPB, facilitating amnesia and reducing systemic vascular resistance. Outside the United States, alternative anesthetic tech- niques, particularly total intravenous anesthesia via propofol and opioid infusions with benzodiazepine supplementation with or without high thoracic epidural anesthesia, are com- monly used. The use of high thoracic epidural anesthesia exerts salutary effects on the coronary circulation as well as myocardial and pulmonary function, attenuates the stress response, and provides prolonged postoperative analge- sia.24,25,35 In the United States, however, concerns about the potential for neuraxial bleeding (particularly in the setting of heparinization, platelet inhibitors, and CPB-induced throm- bocytopenia), local anesthetic toxicity, and logistical issues related to the timing of epidural catheter insertion and management have resulted in limited use of these tech- niques.22 Their selective use in patients with severe pulmo- nary dysfunction (Section 6.5) or chronic pain syndromes may be considered. Although meta-analyses of randomized controlled trials (RCTs) of high thoracic epidural anesthesia/ analgesia in CABG patients (particularly on-pump) have yielded inconsistent results on morbidity and mortality rates, it does appear to reduce time to extubation, pain, and pulmonary complications.36 38 Of interest, although none of the RCTs have reported the occurrence of epidural hematoma or abscess, these entities occur on occasion.38 Finally, the use of other regional anesthetic approaches for postoperative analgesia, such as parasternal block, has been reported.39 Over the past decade, early extubation strategies ( fast- track anesthesia) often have been used in low- to medium- risk CABG patients. These strategies allow a shorter time to extubation, a decreased length of intensive care unit (ICU) stay, and variable effects on length of hospital stay.4 6 Immediate extubation in the operating room, with or without markedly accelerated postoperative recovery pathways (eg, ultra-fast-tracking, rapid recovery protocol, short-stay intensive care ) have been used safely, with low rates of reintubation and no influence on quality of life.40 44 Obser- vational data suggest that physician judgment in triaging lower-risk patients to early or immediate extubation works well, with rates of reintubation 1%.45 Certain factors appear to predict fast-track failure, including previous cardiac surgery, use of intra-aortic balloon counterpulsation, and possibly advanced patient age. Provision of adequate perioperative analgesia is important in enhancing patient mobilization, preventing pulmonary complications, and improving the patient s psychological well-being.9,11 The intraoperative use of high-dose morphine (40 mg) may offer superior postoperative pain relief and enhance patient well-being compared with fentanyl (despite similar times to extubation).46 The safety of nonsteroidal anti-inflammatory agents for analgesia is controversial, with greater evidence for adverse cardiovascular events with the selective cyclooxygenase-2 inhibitors than the nonselective agents. A 2007 AHA Scien- tific statement presented a stepped-care approach to the management of musculoskeletal pain in patients with or at risk for coronary artery disease (CAD), with the goal of limiting the use of these agents to patients in whom safer therapies fail.47 In patients hospitalized with unstable angina (UA) and non ST-elevation myocardial infarction (NSTEMI), these agents should be discontinued promptly and reinstituted later according to the stepped-care approach.48 In the setting of cardiac surgery, nonsteroidal anti- inflammatory agents previously were used for perioperative analgesia. A meta-analysis of 20 trials of patients undergoing thoracic or cardiac surgery, which evaluated studies published before 2005, reported significant reductions in pain scores, with no increase in adverse outcomes.49 Subsequently, 2 RCTs, both studying the oral cyclooxygenase-2 inhibitor valdecoxib and its intravenous prodrug, parecoxib, reported a higher incidence of sternal infections in 1 trial and a significant increase in adverse cardiovascular events in the other.26,27 On the basis of the results of these 2 studies (as well as other nonsurgical reports of increased risk with cyclooxygenase-2 selective agents), the U.S. Food and Drug Administration in 2005 issued a black box warning for all nonsteroidal anti-inflammatory agents (except aspirin) immediately after CABG.50 The concurrent administra- tion of ibuprofen with aspirin has been shown to attenuate the latter s inhibition of platelet aggregation, likely because of competitive inhibition of cyclooxygenase at the platelet-receptor Observational analyses in patients undergoing noncardiac surgery have shown a significant reduction in perioperative death with the use of checklists, multidisciplinary surgical care, intraoperative time-outs, postsurgical debriefings, and other communication strategies.14,15 Such methodology is being used increasingly in CABG patients.12 14 In contrast to extensive literature on the role of the surgeon in determining outcomes with CABG, limited data on the influence of the anesthesiologist are available. Of 2 such reports from single centers in the 1980s, 1 suggested that the failure to control heart rate to 110 beats per minute was associated with a higher mortality rate, and the other suggested that increasing duration of CPB adversely influenced outcome.52,53 Another observational analysis of data from vascular surgery patients suggested that anesthetic specialization was independently associated with a reduction in mortality rate.54 To meet the challenges of providing care for the increasingly higher-risk patients undergoing CABG, efforts have been di- rected at enhancing the experience of trainees, particularly in the use of newer technologies such as TEE. Cardiac anesthesiolo- gists, in collaboration with cardiologists and surgeons, have implemented national training and certification processes for practitioners in the use of perioperative TEE (Section 2.1.7).164,165 Accreditation of cardiothoracic anesthesia fellow- ship programs from the Accreditation Council for Graduate Medical Education was initiated in 2004, and efforts are ongoing to obtain formal subspecialty certification.18 2.1.2. Use of CPB Several adverse outcomes have been attributed to CPB, including 1) neurological deficits (eg, stroke, coma, postop- erative neurocognitive dysfunction); 2) renal dysfunction; and 3) the Systemic inflammatory Response Syndrome (SIRS). The SIRS is manifested as generalized systemic inflammation occurring after a major morbid event, such as trauma, infection, or major surgery. It is often particularly apparent after on-pump cardiac surgery, during which surgi- cal trauma, contact of blood with nonphysiological surfaces (eg, pump tubing, oxygenator surfaces), myocardial ischemia and reperfusion, and hypothermia combine to cause a dra- matic release of cytokines (eg, interleukin [IL] 6 and IL8) and other mediators of inflammation.55 Some investigators have used serum concentrations of S100 beta as a marker of brain injury56 and have correlated increased serum levels with the number of microemboli exiting the CPB circuit during CABG. In contrast, others have noted the increased incidence of microemboli with on-pump CABG (relative to off-pump CABG) but have failed to show a corresponding worsening of neurocognitive function 1 week to 6 months postopera- tively.57,58 Blood retrieved from the operative field during on-pump CABG contains lipid material and particulate mat- ter, which have been implicated as possible causes of post- operative neurocognitive dysfunction. Although a study59 reported that CPB-associated neurocognitive dysfunction can be mitigated by the routine processing of shed blood with a cell saver before its reinfusion, another study60 failed to show such an improvement. It has been suggested that CPB leads to an increased incidence of postoperative renal failure requiring dialysis, but a large RCT comparing on-pump and off-pump CABG showed no difference in its occurrence.61 Of interest, this study failed to show a decreased incidence of postoperative adverse neurological events (stroke, coma, or neurocognitive deficit) in those undergoing off-pump CABG. The occurrence of SIRS in patients undergoing CPB has led to the development of strategies designed to prevent or to minimize its occurrence. Many reports have focused on the increased serum concentrations of cytokines (eg, IL-2R, IL-6, IL-8, tumor necrosis factor alpha) and other modulators of inflammation (eg, P-selectin, sE-selectin, soluble intercellular adhesion molecule-1, plasma endothelial cell adhesion molecule-1, and plasma malondialdehyde), which reflect leukocyte and platelet activation, in triggering the onset of SIRS. A study showed a greater upregulation of neutrophil CD11b expression (a marker of leukocyte activation) in patients who sustained a 50% increase in the serum creatinine concentration after CPB, thereby implicating acti- vated neutrophils in the pathophysiology of SIRS and the occurrence of post-CPB renal dysfunction.62 Modulating neutrophil activation to reduce the occurrence of SIRS has been investigated; however, the results have been inconsis- tent. Preoperative intravenous methylprednisolone (10 mg/ kg) caused a reduction in the serum concentrations of many of these cytokines after CPB, but this reduction was not associ- ated with improved hemodynamic variables, diminished blood loss, less use of inotropic agents, shorter duration of ventilation, or shorter ICU length of stay.63 Similarly, the use of intravenous immunoglobulin G in patients with post-CPB SIRS has not been associated with decreased rates of short- term morbidity or 28-day mortality.64 Other strategies to mitigate the occurrence of SIRS after CPB have been evaluated, including the use of 1) CPB circuits (including oxygenators) coated with materials known to reduce complement and leukocyte activation; 2) CPB tubing that is covalently bonded to heparin; and 3) CPB tubing coated with polyethylene oxide polymer or Poly (2-methoxyethylacrylate). Leukocyte depletion via special- ized filters in the CPB circuits has been shown to reduce the plasma concentrations of P-selectin, intercellular adhesion molecule-1, IL-8, plasma endothelial cell adhesion molecule-1, and plasma malondialdehyde after CPB.65 Finally, closed mini-circuits for CPB have been developed in an attempt to minimize the blood air interface and blood contact with nonbiological surfaces, both of which promote cytokine elaboration, but it is uncertain if these maneuvers and techniques have a discernible effect on outcomes after CABG. 2.1.3. Off-Pump CABG Versus Traditional On-Pump CABG Since the first CABG was performed in the late 1960s, the standard surgical approach has included the use of cardiac arrest coupled with CPB (so-called on-pump CABG), thereby Hillis et al 2011 ACCF/AHA CABG Guideline e659 optimizing the conditions for construction of vascular anas- tomoses to all diseased coronary arteries without cardiac motion or hemodynamic compromise. Such on-pump CABG has become the gold standard and is performed in about 80% of subjects undergoing the procedure in the United States. Despite the excellent results that have been achieved, the use of CPB and the associated manipulation of the ascending aorta are linked with certain perioperative complications, including myonecrosis during aortic occlusion, cerebrovascu- lar accidents, generalized neurocognitive dysfunction, renal dysfunction, and SIRS. In an effort to avoid these complica- tions, off-pump CABG was developed.58,66 Off-pump CABG is performed on the beating heart with the use of stabilizing devices (which minimize cardiac motion); in addition, it incorporates techniques to minimize myocardial ischemia and systemic hemodynamic compromise. As a result, the need for CPB is obviated. This technique does not necessarily de- crease the need for manipulation of the ascending aorta during construction of the proximal anastomoses. To date, the results of several RCTs comparing on-pump and off-pump CABG in various patient populations have been published.61,67,68 In addition, registry data and the results of meta-analyses have been used to assess the relative efficacies of the 2 techniques.69,70 In 2005, an AHA Scientific statement comparing the 2 techniques concluded that both procedures usually result in excellent outcomes and that neither technique should be considered superior to the other.71 At the same time, several differences were noted. Off-pump CABG was associated with less bleeding, less renal dysfunction, a shorter length of hospital stay, and less neurocognitive dysfunction. The inci- dence of perioperative stroke was similar with the 2 techniques. On-pump CABG was noted to be less technically complex and allowed better access to diseased coronary arteries in certain anatomic locations (eg, those on the lateral LV wall) as well as better long-term graft patency. In 2009, the results of the largest RCT to date comparing on-pump CABG to off-pump CABG, the ROOBY (Random- ized On/Off Bypass) trial, were published, reporting the outcomes for 2203 patients (99% men) at 18 Veterans Affairs Medical Centers.61 The primary short-term endpoint, a com- posite of death or complications (reoperation, new mechani- cal support, cardiac arrest, coma, stroke, or renal failure) within 30 days of surgery, occurred with similar frequency (5.6% for on-pump CABG; 7.0% for off-pump CABG; P 0.19). The primary long-term endpoint, a composite of death from any cause, a repeat revascularization procedure, or a nonfatal myocardial infarction (MI) within 1 year of surgery, occurred more often in those undergoing off-pump CABG (9.9%) than in those having on-pump CABG (7.4%; P 0.04). Neuropsychological outcomes and resource utiliza- tion were similar between the 2 groups. One year after surgery, graft patency was higher in the on-pump group (87.8% versus 82.6%; P 0.01). In short, the ROOBY inves- tigators failed to show an advantage of off-pump CABG compared with on-pump CABG in a patient population considered to be at low risk. Instead, use of the on-pump technique was associated with better 1-year composite out- comes and 1-year graft patency rates, with no difference in neuropsychological outcomes or resource utilization. Although numerous investigators have used single- center registries, the STS database, and meta-analyses in an attempt to identify patient subgroups in whom off-pump CABG is the preferred procedure, even these analyses have reached inconsistent conclusions about off-pump CABG s ability to reduce morbidity and mortality rates.69,72 83 A retrospective cohort study of 14 766 consecutive patients undergoing isolated CABG identified a mortality benefit (OR: 0.45) for off-pump CABG in patients with a pre- dicted risk of mortality 2.5%,82 but a subsequent ran- domized comparison of off-pump CABG to traditional on-pump CABG in 341 high-risk patients (a Euroscore 5) showed no difference in the composite endpoint of all-cause death, acute MI, stroke, or a required reinterven- tion procedure.78 An analysis of data from the New York State Cardiac Surgery Reporting system did not demon- strate a reduction in mortality rate with off-pump CABG in any patient subgroup, including the elderly (age 80 years) or those with cerebrovascular disease, azotemia, or an extensively calcified ascending aorta.69 Despite these results, off-pump CABG is the preferred approach by some surgeons who have extensive experience with it and therefore are comfortable with its technical nuances. Recently, published data suggested that the avoidance of aortic manipulation is the most important factor in reducing the risk of neurological complica- tions.84,85 Patients with extensive disease of the ascending aorta pose a special challenge for on-pump CABG; for these patients, cannulation or cross-clamping of the aorta may create an unacceptably high risk of stroke. In such individuals, off-pump CABG in conjunction with avoid- ance of manipulation of the ascending aorta (including placement of proximal anastomoses) may be beneficial. Surgeons typically prefer an on-pump strategy in patients with hemodynamic compromise because CPB offers sup- port for the systemic circulation. In the end, most surgeons consider either approach to be reasonable for the majority of subjects undergoing CABG. 2.1.4. Bypass Graft Conduit: Recommendations Class I 1. If possible, the left internal mammary artery (LIMA) should be used to bypass the left anterior descending (LAD) artery when bypass of the LAD artery is indicated.86 89 (Level of Evidence: B) Class IIa 1. The right internal mammary artery (IMA) is prob- ably indicated to bypass the LAD artery when the LIMA is unavailable or unsuitable as a bypass conduit. (Level of Evidence: C) 2. When anatomically and clinically suitable, use of a second IMA to graft the left circumflex or right coronary artery (when critically stenosed and per- fusing LV myocardium) is reasonable to improve the likelihood of survival and to decrease reinterven- tion.90 94 (Level of Evidence: B) Class IIb 1. Complete arterial revascularization may be reason- able in patients less than or equal to 60 years of age with few or no comorbidities. (Level of Evidence: C) 2. Arterial grafting of the right coronary artery may be reasonable when a critical (>90%) stenosis is pres- ent.89,93,95 (Level of Evidence: B) 3. Use of a radial artery graft may be reasonable when grafting left-sided coronary arteries with severe stenoses (>70%) and right-sided arteries with criti- cal stenoses (>90%) that perfuse LV myocardi- um.96 101 (Level of Evidence: B) Class III: HARM 1. An arterial graft should not be used to bypass the right coronary artery with less than a critical steno- sis (<90%).89 (Level of Evidence: C) Arteries (internal mammary, radial, gastroepiploic, and infe- rior epigastric) or veins (greater and lesser saphenous) may be used as conduits for CABG. The effectiveness of CABG in relieving symptoms and prolonging life is directly related to graft patency. Because arterial and venous grafts have differ- ent patency rates and modes of failure, conduit selection is important in determining the long-term efficacy of CABG. 2.1.4.1. Saphenous Vein Grafts Reversed saphenous vein grafts (SVGs) are commonly used in patients undergoing CABG. Their disadvantage is a de- clining patency with time: 10% to as many as 25% of them occlude within 1 year of CABG89,102,103; an additional 1% to 2% occlude each year during the 1 to 5 years after surgery; and 4% to 5% occlude each year between 6 and 10 years postoperatively.104 Therefore, 10 years after CABG, 50% to 60% of SVGs are patent, only half of which have no angiographic evidence of atherosclerosis.104 During SVG harvesting and initial exposure to arterial pressure, the endo- thelium often is damaged, which, if extensive, may lead to platelet aggregation and graft thrombosis. Platelet adherence to the endothelium begins the process of intimal hyperplasia that later causes SVG atherosclerosis.103,105 After adhering to the intima, the platelets release mitogens that stimulate smooth muscle cell migration, leading to intimal proliferation and hyperplasia. Lipid is incorporated into these areas of intimal hyperplasia, resulting in atherosclerotic plaque forma- tion.106 The perioperative administration of aspirin and dipyr- idamole improves early ( 1 month) and 1-year SVG patency and decreases lipid accumulation in the SVG intima.103,106,107 2.1.4.2. Internal Mammary Arteries Unlike SVGs, IMAs usually are patent for many years postoperatively (10-year patency 90%)89,95,102,108 117 be- cause of the fact that 4% of IMAs develop atherosclerosis, and only 1% have atherosclerotic stenoses of hemodynamic significance.118 120 This resistance to the development of atherosclerosis is presumably due to 1) the nearly continuous internal elastic lamina that prevents smooth muscle cell migration and 2) the release of prostacyclin and nitric oxide, potent vasodilators and inhibitors of platelet function, by the endothelium of IMAs.119,121,122 The disadvantage of using the IMA is that it may spasm and eventually atrophy if used to bypass a coronary artery without a flow-limiting stenosis.89,95,118,123 130 Observational studies suggest an improved survival rate in patients under- going CABG when the LIMA (rather than an SVG) is used to graft the LAD artery86 88; this survival benefit is independent of the patient s sex, age, extent of CAD, and LV systolic function.87,88 Apart from improving survival rate, LIMA grafting of the LAD artery reduces the incidence of late MI, hospitalization for cardiac events, need for reoperation, and recurrence of angina.86,88 The LIMA should be used to bypass the LAD artery provided that a contraindication to its use (eg, emergency surgery, poor LIMA blood flow, subclavian artery stenosis, radiation injury, atherosclerosis) is not present. Because of the beneficial influence on morbidity and mortality rates of using the IMA for grafting, several centers have advocated bilateral IMA grafting in hopes of further improving CABG results.90,91,94 In fact, numerous observa- tional studies have demonstrated improved morbidity and mortality rates when both IMAs are used. On the other hand, bilateral IMA grafting appears to be associated with an increased incidence of sternal wound infections in patients with diabetes mellitus and those who are obese (body mass ). 2.1.4.3. Radial, Gastroepiploic, and Inferior Epigastric Arteries Ever since the observation that IMAs are superior to SVGs in decreasing the occurrence of ischemic events and prolonging survival, other arterial conduits, such as the radial, gastroepi- ploic, and inferior epigastric arteries, have been used in an attempt to improve the results of CABG. Information about these other arterial conduits is sparse in comparison to what is known about IMAs and SVGs, however. The radial artery is a muscular artery that is susceptible to spasm and atrophy when used to graft a coronary artery that is not severely narrowed. Radial artery graft patency is best when used to graft a left-sided coronary artery with 70% stenosis and worst when it is used to bypass the right coronary artery with a stenosis of only moderate severity.96 100 The gastroepiploic artery is most often used to bypass the right coronary artery or its branches, although it may be used to bypass the LAD artery if the length of the gastroepiploic artery is adequate. Similar to the radial artery, it is prone to spasm and therefore should only be used to bypass coronary arteries that are severely stenotic.131 The 1-, 5-, and 10-year patency rates of the gastroepiploic artery are reportedly 91%, The inferior epigastric artery is only 8 to 10 centimeters in length and therefore is usually used as a Y or T graft connected to another arterial conduit. On occasion it is used as a free graft from the aorta to a high diagonal branch of the LAD artery. Because it is a muscular artery, it is prone to spasm and therefore is best used to bypass a severely stenotic coronary artery. Its reported 1-year patency is about 90%.133,134 2.1.5. Incisions for Cardiac Access Although the time-honored incision for CABG is a median sternotomy, surgeons have begun to access the heart via several other approaches in an attempt to 1) reduce the traumatic effects often seen with full median sternotomy, 2) Hillis et al 2011 ACCF/AHA CABG Guideline e661 hasten postoperative recovery, and 3) enhance cosmesis. The utility and benefit of these smaller incisions has been evident in subjects undergoing valvular surgery, for which only limited access to the heart is required. The most minimally invasive access incisions for CABG are seen with robotically assisted totally endoscopic CABG. A study showed that totally endoscopic CABG with robotic technology was associated with improved physical health, shorter hospital stay, and a more rapid return to the activities of daily living compared with traditional techniques. At present, direct comparisons of robotically assisted and con- ventional CABG are lacking.135 The use of minimally invasive cardiac access incisions for CABG is limited. The need for adequate exposure of the ascending aorta and all surfaces of the heart to accomplish full revascularization usually precludes the use of minimal access incisions, such as upper sternotomy, lower sternotomy, or anterolateral thoracotomy. Nevertheless, use of limited incisions may increase in the future with the advent of hybrid strategies that use a direct surgical approach (usually for grafting the LAD artery through a small parasternal incision) and percutaneous coronary intervention (PCI) of the other diseased coronary arteries. The benefit of hybrid revascular- ization and hybrid operating rooms, in which PCI and CABG can be accomplished in one procedure, is yet to be deter- mined. In patients with certain comorbid conditions, such as severe aortic calcification, previous chest irradiation, and obesity in combination with severe diabetes mellitus, full median sternotomy may be problematic,136 and hybrid revas- cularization may be preferable. 2.1.6. Anastomotic Techniques At present, most coronary bypass grafts are constructed with hand-sewn suture techniques for the proximal and distal anastomoses, a practice that has resulted in good short- and intermediate-term patency rates. Because surgeons have dif- ferent preferences with regard to the technical aspects of the procedure, a wide variety of suture configurations is used. Sewing of the proximal and distal anastomoses with a continuous polypropylene suture is commonly done, but techniques with interrupted silk sutures have been used, with similar results for graft patency and adverse events. Certain clinical scenarios have precipitated an interest in alternative techniques of constructing coronary bypass anas- tomoses. Some surgeons and patients wish to avoid the potential morbidity and cosmetic results of a median sternot- omy, yet the least invasive incisions usually are too small to allow hand-sewn anastomoses. To solve this problem, coro- nary connector devices have been developed for use with arterial or venous conduits to enable grafting without direct suturing. In addition, these devices have been used in subjects with diseased ascending aortas, in whom a technique that allows construction of a proximal anastomosis with minimal manipulation of the ascending aorta (typically by eliminating the need for aortic cross-clamping) may result in less embo- lization of debris, thereby reducing the occurrence of adverse neurological outcomes. In this situation, the operation is performed through a median sternotomy, and the proximal anastomoses are created with a connector (or may be hand- sewn with the assistance of a device that provides a bloodless operative field) without partial or complete clamping of the ascending aorta. 2.1.7. Intraoperative TEE: Recommendations Class I 1. Intraoperative TEE should be performed for evalu- ation of acute, persistent, and life-threatening hemo- dynamic disturbances that have not responded to treatment.137,138 (Level of Evidence: B) 2. Intraoperative TEE should be performed in patients undergoing concomitant valvular surgery.137,139 (Level of Evidence: B) Class IIa 1. Intraoperative TEE is reasonable for monitoring of hemodynamic status, ventricular function, regional wall motion, and valvular function in patients un- dergoing CABG.138,140 145 (Level of Evidence: B) The use of intraoperative TEE in patients undergoing cardiac surgery has increased steadily since its introduction in the late 1980s. Although its utility is considered to be highest in patients undergoing valvular and complex open great-vessel/ aortic surgery, it is commonly used in subjects undergoing CABG. TEE is most often used,146 although epicardial and epiaortic imaging, performed under aseptic conditions, allows visualization of imaging planes not possible with TEE.147,148 specifically, epiaortic imaging allows visualization of the blind spot of the ascending aorta (caused by interposition of the trachea with the esophagus), the site of aortic cannulation for CPB, from which dislodgement of friable atheroma, a major risk factor for perioperative stroke, may occur (Section 5.2.1). In addition, epicardial probes allow imaging when TEE is contraindicated, cannot be performed, or produces inadequate images. It can facilitate the identification of intraventricular thrombi when TEE images are equivocal. The 2003 ACC/AHA/ASE Guideline Update for the Clinical Application of Echocardiography based its recom- mendations on those reported in the 1996 American Society of Anesthesiologists/Society of Cardiovascular Anesthesiol- ogists practice guideline and considered the use of TEE in CABG patients.149 The latter document was updated in 2010.139 Because of the use of different grading methodolo- gies in the American Society of Anesthesiologists/Society of Cardiovascular Anesthesiologists guideline relative to that of the ACCF/AHA, precise comparisons are difficult. However, it is noted that TEE should be considered in subjects undergoing CABG, to confirm and refine the preoperative diagnosis, detect new or unsuspected pathology, adjust the anesthetic and surgical plan accordingly, and assess the results of surgery. The strongest recommendation is given for treatment of acute life-threatening hemodynamic instability that has not responded to conventional therapies. Observational cohort analyses and case reports have sug- gested the utility of TEE for diagnosing acute life-threatening hemodynamic or surgical problems in CABG patients, many of which are difficult or impossible to detect or treat without direct imaging. Evaluation of ventricular cross-sectional areas and ejection fraction (EF) and estimation or direct measure- ment of cardiac output by TEE may facilitate anesthetic, fluid, and inotropic/pressor management. The utility of echo- cardiography for the evaluation of LV end-diastolic area/ volume and its potential superiority over pulmonary artery occlusion or pulmonary artery diastolic pressure, particularly in the early postoperative period, has been reported150,151 (Section 4.10). In subjects without preoperative transthoracic imaging, intraoperative TEE may provide useful diagnostic information (over and above that detected during cardiac catheterization) on valvular function as well as evidence of pulmonary hypertension, intracardiac shunts, or other com- plications that may alter the planned surgery. In patients undergoing CABG, intraoperative TEE is used most often for the detection of regional wall motion abnor- malities (possibly caused by myocardial ischemia or infarc- tion) and their effect on LV function. Observational studies have suggested that regional wall motion abnormalities de- tected with TEE can guide surgical therapy, leading to revision of a failed or inadequate conduit or the placement of additional grafts not originally planned. The presence of new wall motion abnormalities after CPB correlates with adverse perioperative and long-term outcomes.143 Although the initial hope that an estimation of coronary blood flow with intramyocardial contrast enhancement visu- alized by TEE would facilitate surgical intervention has not been realized, technical advances in imaging of coronary arteries and grafts may ultimately provide reliable informa- tion. At present, the evaluation of graft flow with conven- tional nonimaging handheld Doppler probes appears adequate (Section 8). Intraoperative evaluation of mitral regurgitation may facilitate detection of myocardial ischemia and provide guidance about the need for mitral valve annuloplasty (Sec- tion 6.7). Newer technologies, including nonimaging methods for analyzing systolic and diastolic velocity and direction and timing of regional wall motion (Doppler tissue imaging and speckle tracking), as well as real-time 3-dimensional im- aging, may facilitate the diagnosis of myocardial ischemia and evaluation of ventricular function. At present, however, their cost-effectiveness has not been determined, and they are too complex for routine use.152 154 Among different centers, the rate of intraoperative TEE use in CABG patients varies from none to routine; its use is influenced by many factors, such as institutional and practi- tioner preferences, the healthcare system and reimbursement strategies, tertiary care status, and presence of training pro- grams.155 The efficacy of intraoperative TEE is likely influ- enced by the presence of 1) LV systolic and diastolic dysfunction, 2) concomitant valvular disease, 3) the planned surgical procedure (on pump versus off pump, primary versus reoperative), 4) the surgical approach (full sternotomy versus partial sternotomy versus endoscopic or robotic), 5) its acuity (elective versus emergency); and 6) physician training and The safety of intraoperative TEE in patients undergoing cardiac surgery is uncertain. Retrospective analyses of data from patients undergoing diagnostic upper gastrointestinal endoscopy, nonoperative diagnostic TEE imaging, and intra- operative imaging by skilled operators in high-volume cen- ters demonstrate a low frequency of complications related to insertion or manipulation of the probe.164,165 Nevertheless, minor (primarily pharyngeal injury from probe insertion) and major (esophageal perforation, gastric bleeding, or late me- diastinitis) complications are reported.166,167 A more indolent complication is that of acquired dysphagia and possible aspiration postoperatively. Although retrospective analyses of postoperative cardiac surgical patients with clinically mani- fest esophageal dysfunction have identified TEE use as a risk factor,168 170 such dysfunction also has been reported in subjects in whom TEE was not used.171 Advanced age, prolonged intubation, and neurological injury seem to be risk factors for its development. The significance of the incidental intraoperative detection and repair of a patent foramen ovale, a common occurrence, is controversial.172 A 2009 observa- tional analysis of 13 092 patients (25% isolated CABG; 29% CABG or other cardiac procedure), of whom 17% had a patent foramen ovale detected by TEE (28% of which were repaired), reported an increase in postoperative stroke in the patients who had patent foramen ovale repair (OR: 2.47; 95% CI: 1.02 to 6.0) with no improvement in long-term 2.1.8. Preconditioning/Management of Myocardial Ischemia: Recommendations Class I 1. Management targeted at optimizing the determinants of coronary arterial perfusion (eg, heart rate, diastolic or mean arterial pressure, and right ventricular or LV end-diastolic pressure) is recommended to reduce the risk of perioperative myocardial ischemia and infarc- tion.53,174 177 (Level of Evidence: B) Class IIa 1. Volatile-based anesthesia can be useful in reducing the risk of perioperative myocardial ischemia and infarction.178 181 (Level of Evidence: A) Class IIb 1. The effectiveness of prophylactic pharmacological therapies or controlled reperfusion strategies aimed at inducing preconditioning or attenuating the ad- verse consequences of myocardial reperfusion injury or surgically induced systemic inflammation is un- certain.182 189 (Level of Evidence: A) 2. Mechanical preconditioning might be considered to reduce the risk of perioperative myocardial ischemia and infarction in patients undergoing off-pump CABG.190 192 (Level of Evidence: B) 3. Remote ischemic preconditioning strategies using pe- ripheral-extremity occlusion/reperfusion might be con- sidered to attenuate the adverse consequences of myo- cardial reperfusion injury.193 195 (Level of Evidence: B) 4. The effectiveness of postconditioning strategies to at- tenuate the adverse consequences of myocardial reper- fusion injury is uncertain.196,197 (Level of Evidence: C) See Online Data Supplements 2 to 4 for additional data on preconditioning. Hillis et al 2011 ACCF/AHA CABG Guideline e663 Perioperative myocardial injury is associated with adverse outcomes after CABG,198 200 and available data suggest a direct correlation between the amount of myonecrosis and the likelihood of an adverse outcome198,201 204 (Section 5.2.4). The etiologies of perioperative myocardial ischemia and infarction and their complications (electrical or mechanical) range from alterations in the determinants of global or regional myocardial oxygen supply and demand to complex biochemical and microanatomic, systemic, or vascular abnor- malities, many of which are not amenable to routine diagnos- tic and therapeutic interventions. Adequate surgical reperfu- sion is important in determining outcome, even though it may initially induce reperfusion injury. Various studies delineat- ing the major mediators of reperfusion injury have focused attention on the mitochondrial permeability transition pore, the opening of which during reperfusion uncouples oxidative phosphorylation, ultimately leading to cell death.205 Although several pharmacological interventions targeting components of reperfusion injury have been tried, none has been found to be efficacious for this purpose.182,184 189,205 207 The severity of reperfusion injury is influenced by numer- ous factors, including 1) the status of the patient s coronary circulation, 2) the presence of active ongoing ischemia or infarction, 3) preexisting medical therapy (Sections 4.3 and 4.5), 4) concurrent use of mechanical assistance to improve coronary perfusion (ie, intra-aortic balloon counterpulsation), and 5) the surgical approach used (on pump or off pump). CPB with ischemic arrest is known to induce the release of cytokines and chemokines involved in cellular homeostasis, thrombosis, and coagulation; oxidative stress; adhesion of blood cell elements to the endothelium; and neuroendocrine stress responses; all of these may contribute to myocardial injury.208,209 Controlled reperfusion strategies during CPB, involving prolonged reperfusion with warm-blood cardiople- gia in conjunction with metabolic enhancers, are rarely used in lieu of more routine methods of preservation (eg, asystolic arrest, anterograde or retrograde blood cardioplegia during aortic cross-clamping). Several studies suggest that the mag- nitude of SIRS is greater with on-pump CABG than with Initial studies of preconditioning used mechanical occlusion of arterial inflow followed by reperfusion via aortic cross- clamping immediately on institution of bypass or with coronary artery occlusion proximal to the planned distal anastomosis during off-pump CABG.190,191,214 217 Because of concerns of the potential adverse cerebral effects of aortic manipulation, enthu- siasm for further study of this technique in on-pump CABG patients is limited (Section 5.2.1). Despite intense interest in the physiology of postconditioning, few data are available.197 A small 2008 study in patients undergoing valve surgery, which used repeated manipulation of the ascending aorta, reported a reduction in surrogate markers of inflammation and myo- necrosis.196 In lieu of techniques utilizing mechanical occlusion, pharmacological conditioning agents are likely to be used. An alternative approach that avoids much (but not all) of the safety concerns related to potential vascular injury is remote precondi- tioning of arterial inflow to the leg or (more commonly) the arm via blood pressure cuff occlusion.218 Two studies of patients undergoing on-pump CABG at a single center, the first of which used 2 different myocardial protection strategies and the second of which repeated the study with a standardized cold-blood cardioplegia routine, reported similar amounts of troponin re- lease during the 72 hours postoperatively, with no apparent complications.193,195 A larger trial was unable to confirm any benefits of a similar protocol, casting doubt on the utility of this Volatile halogenated anesthetics and opioids have anti- ischemic or conditioning properties,32,33,219,220 and propofol has antioxidant properties of potential value in subjects with reperfusion injury.221,222 The salutary properties of volatile anesthetics during myocardial ischemia are well known. 