Internal thoracic arteries (ITAs) should be used to bypass the left anterior descending (LAD) artery when bypass of the LAD is indicated (class of recommendation [COR] I, level of evidence [LOE] B). As an adjunct to left internal thoracic artery (LITA), a second arterial graft (right ITA or radial artery [RA]) should be considered in appropriate patients (COR IIa, LOE B). Use of bilateral ITAs (BITAs) should be considered in patients who do not have an excessive risk of sternal complications (COR IIa, LOE B). To reduce the risk of sternal infection with BITA, skeletonized grafts should be considered (COR IIa, LOE B), smoking cessation is recommended (COR I, LOE C), glycemic control should be considered (COR IIa, LOE B), and enhanced sternal stabilization may be considered (COR IIb, LOE C). As an adjunct to LITA to LAD (or in patients with inadequate LITA grafts), use of a RA graft is reasonable when grafting coronary targets with severe stenoses (COR IIa, LOE: B). When RA grafts are used, it is reasonable to use pharmacologic agents to reduce acute intraoperative and perioperative spasm (COR IIa, LOE C). The right gastroepiploic artery may be considered in patients with poor conduit options or as an adjunct to more complete arterial revascularization (COR IIb, LOE B). Use of arterial grafts (specific targets, number, and type) should be a part of the discussion of the heart team in determining the optimal approach for each patient (COR I, LOE C). Internal thoracic arteries (ITAs) should be used to bypass the left anterior descending (LAD) artery when bypass of the LAD is indicated (class of recommendation [COR] I, level of evidence [LOE] B). As an adjunct to left internal thoracic artery (LITA), a second arterial graft (right ITA or radial artery [RA]) should be considered in appropriate patients (COR IIa, LOE B). Use of bilateral ITAs (BITAs) should be considered in patients who do not have an excessive risk of sternal complications (COR IIa, LOE B). To reduce the risk of sternal infection with BITA, skeletonized grafts should be considered (COR IIa, LOE B), smoking cessation is recommended (COR I, LOE C), glycemic control should be considered (COR IIa, LOE B), and enhanced sternal stabilization may be considered (COR IIb, LOE C). As an adjunct to LITA to LAD (or in patients with inadequate LITA grafts), use of a RA graft is reasonable when grafting coronary targets with severe stenoses (COR IIa, LOE: B). When RA grafts are used, it is reasonable to use pharmacologic agents to reduce acute intraoperative and perioperative spasm (COR IIa, LOE C). The right gastroepiploic artery may be considered in patients with poor conduit options or as an adjunct to more complete arterial revascularization (COR IIb, LOE B). Use of arterial grafts (specific targets, number, and type) should be a part of the discussion of the heart team in determining the optimal approach for each patient (COR I, LOE C). For related article, see page 419 For related article, see page 419 The Appendix and Online Supplement can be viewed in the online version of this article [http://dx.doi.org/10.1016/j.athoracsur.2015.09.100] on http://www.annalsthoracidsurgery.org. The Appendix and Online Supplement can be viewed in the online version of this article [http://dx.doi.org/10.1016/j.athoracsur.2015.09.100] on http://www.annalsthoracidsurgery.org. As the techniques of surgical and percutaneous coronary revascularization for coronary artery disease (CAD) continue to evolve, reassessing available data to inform decision making should take place periodically. This expert writing group was charged with developing balanced, patient-focused recommendations for clinical practice that aim to improve the quality of care, optimize individual patient outcomes, and favorably affect costs by focusing resources on the most effective strategies. Prior multi-society documents have focused on indications and outcomes of coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) in the treatment of multivessel CAD. This guideline assessed how the choice of arterial conduits can affect outcomes. In the past two decades, despite a decreasing rate of morbidity and mortality [1ElBardissi A.W. Aranki S.F. Sheng S. O'Brien S.M. Greenberg C.C. Gammie J.S. Trends in isolated coronary artery bypass grafting: an analysis of the Society of Thoracic Surgeons adult cardiac surgery database.J Thorac Cardiovasc Surg. 2012; 143: 273-281Abstract Full Text Full Text PDF PubMed Scopus (342) Google Scholar, 2Movahed M.R. Ramaraj R. Khoynezhad A. Hashemzadeh M. Hashemzadeh M. Declining in-hospital deaths in patients undergoing coronary bypass surgery in the United States irrespective of presence of type 2 diabetes or congestive heart failure.Clin Cardiol. 2012; 35: 297-300Crossref PubMed Scopus (16) Google Scholar, 3Ferguson Jr., T.B. Hammill B.G. Peterson E.D. DeLong E.R. Grover F.L. STS National Database CommitteeA decade of change–risk profiles and outcomes for isolated coronary artery bypass grafting procedures, 1990–1999: a report from the STS National Database Committee and the Duke Clinical Research Institute. Society of Thoracic Surgeons.Ann Thorac Surg. 2002; 73 (discussion 489–90): 480-489Abstract Full Text Full Text PDF PubMed Scopus (554) Google Scholar], the overall rate of CABG in North America has declined by more than 23%. An analysis of The Society of Thoracic Surgeons (STS) Adult Cardiac Surgical Database (ACSD) shows that isolated CABG procedures peaked in 1997 at 191,581 and declined to 146,947 procedures by 2012. When adjustments are made for the growing adult US population, a much more significant decline of nearly 38% for CABG is noted from 2001 to 2008 (from 1,742 to 1,081 CABG procedures per million adults per year; p < 0.001) [4Epstein A.J. Polsky D. Yang F. Yang L. Groeneveld P.W. Coronary revascularization trends in the United States, 2001–2008.JAMA. 2011; 305: 1769-1776Crossref PubMed Scopus (434) Google Scholar, 5Riley R.F. Don C.W. Powell W. Maynard C. Dean L.S. Trends in coronary revascularization in the United States from 2001 to 2009: recent declines in percutaneous coronary intervention volumes.Circ Cardiovasc Qual Outcomes. 2011; 4: 193-197Crossref PubMed Scopus (151) Google Scholar]. This decline may have been caused by (1) improvements in medical therapy and secondary prevention of stable angina [6Vedin O. Hagstrom E. Stewart R. et al.Secondary prevention and risk factor target achievement in a global, high-risk population with established coronary heart disease: baseline results from the STABILITY study.Eur J Prev Cardiol. 2013; 20: 678-685Crossref PubMed Scopus (52) Google Scholar], (2) improvements in stent technology and adjuvant medical therapy that have achieved intermediate-term outcomes similar to surgical revascularization, and (3) desire by patients to avoid the invasiveness and short-term risks of surgical intervention. Consequently, patients referred for a surgical procedure in the current era have more extensive coronary disease burden and coexisting morbidities such as diabetes, hypertension, chronic obstructive pulmonary disease (COPD), peripheral vascular disease, hyperlipidemia, and frailty [7Cao C. Manganas C. Horton M. et al.Angiographic outcomes of radial artery versus saphenous vein in coronary artery bypass graft surgery: a meta-analysis of randomized controlled trials.J Thorac Cardiovasc Surg. 2013; 146: 255-261Abstract Full Text Full Text PDF PubMed Scopus (89) Google Scholar, 8Aldea G.S. Mokadam N.A. Melford Jr., R. et al.Changing volumes, risk profiles, and outcomes of coronary artery bypass grafting and percutaneous coronary interventions.Ann Thorac Surg. 2009; 87: 1828-1838Abstract Full Text Full Text PDF PubMed Scopus (35) Google Scholar, 9Buth K.J. Gainer R.A. Legare J.F. Hirsch G.M. The changing face of cardiac surgery: practice patterns and outcomes 2001–2010.Can J Cardiol. 2014; 30: 224-230Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar, 10Mokadam N.A. Melford Jr., R.E. Maynard C. et al.Prevalence and procedural outcomes of percutaneous coronary intervention and coronary artery bypass grafting in patients with diabetes and multivessel coronary artery disease.J Card Surg. 2011; 26: 1-8Crossref PubMed Scopus (12) Google Scholar]. Despite these higher-risk patients, surgeons are required to provide superior short-term surgical outcomes, minimal patient morbidity, and durable long-term outcomes and graft patency. In the subset of patients who are candidates for either surgical or percutaneous interventions, older randomized trials failed to detect significant differences in short-term death and myocardial infarction (MI) rates, but they consistently observed higher rates of repeat revascularization after PCI compared with CABG [11Hlatky M.A. Boothroyd D.B. Bravata D.M. et al.Coronary artery bypass surgery compared with percutaneous coronary interventions for multivessel disease: a collaborative analysis of individual patient data from ten randomised trials.Lancet. 2009; 373: 1190-1197Abstract Full Text Full Text PDF PubMed Scopus (596) Google Scholar, 12Daemen J. Boersma E. Flather M. et al.Long-term safety and efficacy of percutaneous coronary intervention with stenting and coronary artery bypass surgery for multivessel coronary artery disease: a meta-analysis with 5-year patient-level data from the ARTS, ERACI-II, MASS-II, and SoS trials.Circulation. 2008; 118: 1146-1154Crossref PubMed Scopus (252) Google Scholar]. However, large registries that used propensity-matched analyses showed improved survival with CABG [13Hlatky M.A. Boothroyd D.B. Baker L. et al.Comparative effectiveness of multivessel coronary bypass surgery and multivessel percutaneous coronary intervention: a cohort study.Ann Intern Med. 2013; 158: 727-734Crossref PubMed Scopus (60) Google Scholar, 14Weintraub W.S. Grau-Sepulveda M.V. Weiss J.M. et al.Comparative effectiveness of revascularization strategies.N Engl J Med. 2012; 366: 1467-1476Crossref PubMed Scopus (460) Google Scholar]. In the more current SYNTAX (SYNergy Between PCI [percutaneous coronary intervention] With TAXUS and Cardiac Surgery) trial, differences between PCI and CABG were accentuated and continue to diverge over time in patients undergoing PCI with a high or intermediate SYNTAX score (less than 23) for repeat revascularization and for death and MI [15Kappetein A.P. Feldman T.E. Mack M.J. et al.Comparison of coronary bypass surgery with drug-eluting stenting for the treatment of left main and/or three-vessel disease: 3-year follow-up of the SYNTAX trial.Eur Heart J. 2011; 32: 2125-2134Crossref PubMed Scopus (455) Google Scholar, 16Mohr F.W. Morice M.C. Kappetein A.P. et al.Coronary artery bypass graft surgery versus percutaneous coronary intervention in patients with three-vessel disease and left main coronary disease: 5-year follow-up of the randomised, clinical SYNTAX trial.Lancet. 2013; 381: 629-638Abstract Full Text Full Text PDF PubMed Scopus (1249) Google Scholar]. In this population, favorable outcomes with CABG were attributed to more complete revascularization and improved graft patency. In recent decades there has been dramatic evolution in PCI technologies, from balloon angioplasty to newer generations of drug-eluting stents, and periprocedural medical therapies that range from long-term dual antiplatelet therapy to the ubiquitous use of antistatins. In contrast, there has been little change in choice of conduits for CABG, and the use of multiple arterial grafting remains low. For the past few decades, most surgeons in the STS ACSD perform a single arterial bypass of the left internal thoracic artery (LITA) to the left anterior descending (LAD) and saphenous vein grafts (SVGs) to remaining targets. In the SYTNAX trial that compared CABG with PCI, almost all of the patients undergoing CABG (97.3%) received at least one arterial conduit bypass and 35.3% of patients received more than one arterial conduit [17Mohr F.W. Rastan A.J. Serruys P.W. et al.Complex coronary anatomy in coronary artery bypass graft surgery: impact of complex coronary anatomy in modern bypass surgery? Lessons learned from the SYNTAX trial after two years.J Thorac Cardiovasc Surg. 2011; 141: 130-140Abstract Full Text Full Text PDF PubMed Scopus (108) Google Scholar]. The US sites had a significantly lower rate at 17% [18Head S.J. Parasca C.A. Mack M.J. et al.Differences in baseline characteristics, practice patterns and clinical outcomes in contemporary coronary artery bypass grafting in the United States and Europe: insights from the SYNTAX randomized trial and registry.Eur J Cardiothorac Surg. 2015; 46 (discussion 408): 400-408Google Scholar]. In the STS ACSD, the current incidence of a second arterial graft is less than 7% (1990 to 1999, 3.2%; 2000 to 2009, 11.6%; and 2010 to 2013, 6.7%) [19The Society of Thoracic Surgeons. Adult Cardiac Surgery Database. Chicago: The Society; 2014.Google Scholar]. Because many studies have reported SVG failure rates of up to 10% to 20% after 1 year and an additional 5% failure rate for each subsequent year [20Goldman S. Zadina K. Moritz T. et al.Long-term patency of saphenous vein and left internal mammary artery grafts after coronary artery bypass surgery: results from a Department of Veterans Affairs Cooperative Study.J Am Coll Cardiol. 2004; 44: 2149-2156Abstract Full Text Full Text PDF PubMed Scopus (716) Google Scholar, 21McLean R.C. Nazarian S.M. Gluckman T.J. et al.Relative importance of patient, procedural and anatomic risk factors for early vein graft thrombosis after coronary artery bypass graft surgery.J Cardiovasc Surg (Torino). 2011; 52: 877-885PubMed Google Scholar, 22Halabi A.R. Alexander J.H. Shaw L.K. et al.Relation of early saphenous vein graft failure to outcomes following coronary artery bypass surgery.Am J Cardiol. 2005; 96: 1254-1259Abstract Full Text Full Text PDF PubMed Scopus (92) Google Scholar], it is logical to infer that if the surgical conduit failure rate can be ameliorated by safe, more judicious, and effective use of arterial grafts, long-term clinical outcomes may be significantly improved. The most commonly reported coronary revascularization outcome measures are all-cause death and graft patency. All-cause death is a hard end point that can be reliably measured. Because there is no universally accepted definition (or assessment) of graft patency or failure, this end point is harder to report and compare. The STS Workforce on Evidence-Based Surgery assembled a task force in 2013 to address factors that guide the use of potential arterial and venous conduits in CABG procedures. All Task Force members were required to submit a disclosure form listing any potential conflict of interest from the period starting 36 months prior to initiating the guideline. The full responses are available as an Online Supplement. A systematic review was outlined, and searches were run in MEDLINE, Embase, and the Cochrane databases. Results were limited to papers published on human subjects in English since January 1, 2000. The following search terms were used to identify relevant studies: “coronary artery bypass graft,” “CABG,” “bilateral internal mammary artery,” “bilateral internal thoracic artery,” “left internal mammary artery,” “right internal thoracic artery,” “radial artery,” “gastroepiploic artery,” “patency,” “overall survival,” “mortality,” “morbidity,” “reoperation,” “sternal infection and malunion.” We augmented our literature search by manually reviewing the identified studies. Abstracts were reviewed by at least two individuals for relevance. The initial approximately 1,500 results were reduced if they were case reports, had a primary focus of PCI, were population-based studies that covered incidence and risk factors for CABG, sought to identify potential secondary outcomes or markers, or included study populations of specific subgroups that will be a focus of subsequent STS guidelines. The remaining 103 relevant clinical studies were analyzed in the evidence and critical appraisal tables in the Appendix by three authors (S. Fremes, S. Firestone, and F. Bakaeen). Guideline recommendations were formulated and reviewed by all members of the writing group before approval by the Workforce on Evidence-Based Surgery and the STS Executive Committee. The class of recommendation (COR) is an estimate of the size of the treatment effect that consider risks versus benefits in addition to evidence or agreement that a given treatment or procedure is or is not useful/effective. The level of evidence (LOE) is an estimate of the certainty or precision of the treatment effect (Table 1).Table 1Description of COR and LOEDescriptionCOR Class I (benefit > > >risk)Procedure/treatment should be performed/administered. Class IIA (benefit >>risk)Additional studies with focused objectives needed; it is reasonable to perform procedure/administer treatment Class IIB (benefit > risk)Additional studies with broad objectives needed; additional registry data would be helpful; procedure/treatment may be considered Class III (no benefit)Procedure/test: not helpful; treatment: no proven benefit Class III (harm)Procedure: without benefit or harmful; treatment: harmful to patientsLOE that best fits the recommendation Level AMultiple populations evaluated; data derived from multiple randomized clinical trials or meta-analyses Level BLimited populations evaluated; data derived from a single randomized trial or nonrandomized studies Level CVery limited populations evaluated; only consensus opinion of experts, case studies, or standard of care are availableCOR = classification of recommendation; LOE = level of evidence. Open table in a new tab COR = classification of recommendation; LOE = level of evidence. The LITA is the gold standard conduit in CABG and has consistently shown to be associated with improved survival, graft patency, and freedom from cardiac events compared with SVG conduits. The LITA is used routinely to bypass the LAD artery when considerable disease is present, provided that contraindications to its use are not present (eg, poor LITA blood flow, extreme risk of sternal infection/malunion). This is thought to be because of the unique vascular biology of the internal thoracic artery and the large territorial run-off when the LITA is used to bypass the LAD. Data suggest that arterial grafts may also mitigate progression of native CAD [23Dimitrova K.R. Hoffman D.M. Geller C.M. Dincheva G. Ko W. Tranbaugh R.F. Arterial grafts protect the native coronary vessels from atherosclerotic disease progression.Ann Thorac Surg. 2012; 94: 475-481Abstract Full Text Full Text PDF PubMed Scopus (115) Google Scholar]. The mammary pedicle may provide some protection for the artery at the expense of greater sternal ischemia [24Knobloch K. Lichtenberg A. Pichlmaier M. et al.Microcirculation of the sternum following harvesting of the left internal mammary artery.Thoracic Cardiovasc Surg. 2003; 51: 255-259Crossref PubMed Scopus (46) Google Scholar, 25Lorberboym M. Medalion B. Bder O. et al.99mTc-MDP bone SPECT for the evaluation of sternal ischaemia following internal mammary artery dissection.Nucl Med Commun. 2002; 23: 47-52Crossref PubMed Scopus (39) Google Scholar]. Alternatively, the internal thoracic arteries can be harvested in a skeletonized fashion or with a surrounding myofascial pedicle. Skeletonization was thought to potentially increase the likelihood of damage to the artery due to lack of surrounding soft tissue, but reported patency rates are similar between skeletonized and pedicle ITAs [26Ali E. Saso S. Ashrafian H. Athanasiou T. Does a skeletonized or pedicled left internal thoracic artery give the best graft patency?.Interact Cardiovasc Thorac Surg. 2010; 10: 97-104Crossref PubMed Scopus (24) Google Scholar]. Several reports suggested that harvesting the ITA in the skeletonized fashion compared with pedicled grafts preserves sternal blood flow and, along with enhanced sternal reinforcement, significantly reduces the risk of wound infection [27Hu X. Zhao Q. Skeletonized internal thoracic artery harvest improves prognosis in high-risk population after coronary artery bypass surgery for good quality grafts.Ann Thorac Surg. 2011; 92: 48-58Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar, 28Sakic A. Chevtchik O. Kilo J. et al.Simple adaptations of surgical technique to critically reduce the risk of postoperative sternal complications in patients receiving bilateral internal thoracic arteries.Interact Cardiovasc Thorac Surg. 2013; 17: 378-382Crossref PubMed Scopus (19) Google Scholar]. This is especially relevant in patients with diabetes mellitus (DM) with single ITA (SITA) and bilateral ITA (BITA) use [29Toumpoulis I.K. Theakos N. Dunning J. Does bilateral internal thoracic artery harvest increase the risk of mediastinitis?.Interact Cardiovasc Thorac Surg. 2007; 6: 787-791Crossref PubMed Scopus (71) Google Scholar]. Large nonrandomized risk-adjusted registry data and meta-analyses have reported safety and efficacy of BITA grafting [30Itagaki S. Cavallaro P. Adams D.H. Chikwe J. Bilateral internal mammary artery grafts, mortality and morbidity: an analysis of 1 526 360 coronary bypass operations.Heart. 2013; 99: 849-853Crossref PubMed Scopus (69) Google Scholar, 31Weiss A.J. Zhao S. Tian D.H. Taggart D.P. Yan T.D. A meta-analysis comparing bilateral internal mammary artery with left internal mammary artery for coronary artery bypass grafting.Ann Cardiothorac Surg. 2013; 2: 390-400PubMed Google Scholar, 32Glineur D. D'Hoore W. Price J. et al.Survival benefit of multiple arterial grafting in a 25-year single-institutional experience: the importance of the third arterial graft.Eur J Cardiothorac Surg. 2012; 42 (discussion 290–1): 284-290Crossref PubMed Scopus (61) Google Scholar, 33Tatoulis J. Buxton B.F. Fuller J.A. The right internal thoracic artery: the forgotten conduit–5,766 patients and 991 angiograms.Ann Thorac Surg. 2011; 92 (discussion 15–7): 9-15Abstract Full Text Full Text PDF PubMed Scopus (173) Google Scholar]. The use of both ITAs was associated with decreased risk of death, reoperation, and PCI. A recent study found that BITA with the use of the right ITA (RITA) bypass to the LAD and the LITA to another left-sided coronary vessel has comparable outcomes with a BITA with LITA to the LAD and RITA to a left-sided coronary bypass (RITA late death hazard ratio [HR] 0.78, 95% confidence interval [CI]: 0.48 to 1.26; and repeat revascularization HR 0.83, 95% CI: 0.7 to 2.42) [34Raja S.G. Benedetto U. Husain M. et al.Does grafting of the left anterior descending artery with the in situ right internal thoracic artery have an impact on late outcomes in the context of bilateral internal thoracic artery usage?.J Thorac Cardiovasc Surg. 2014; 148 (Erratum in: J thorac Cardiovasc Surg 2015;149:947): 1275-1281Abstract Full Text Full Text PDF PubMed Scopus (40) Google Scholar]. Three meta-analyses of retrospective studies compared SITA with BITA grafts and found HRs of 0.8 for overall survival and lower re-intervention rates, favoring BITA. The beneficial impacts of BITA compared with LITA grafting on survival and major adverse cardiac events may be delayed by as much as a 7 to 10 years but persist beyond that time period; thus, they may be less appreciated in older patients with coexistent morbidities with more limited life expectancy [35Kieser T.M. Lewin A.M. Graham M.M. et al.Outcomes associated with bilateral internal thoracic artery grafting: the importance of age.Ann Thorac Surg. 2011; 92 (discussion 1275–6): 1269-1275Abstract Full Text Full Text PDF PubMed Scopus (91) Google Scholar, 36Mohammadi S. Dagenais F. Doyle D. et al.Age cut-off for the loss of benefit from bilateral internal thoracic artery grafting.Eur J Cardiothorac Surg. 2008; 33: 977-982Crossref PubMed Scopus (55) Google Scholar]. In addition, certain subset of patients, specifically patients with DM, may derive specific survival benefits from BITA grafting [37Raza S. Sabik 3rd, J.F. Masabni K. Ainkaran P. Lytle B.W. Blackstone E.H. Surgical revascularization techniques that minimize surgical risk and maximize late survival after coronary artery bypass grafting in patients with diabetes mellitus.J Thorac Cardiovasc Surg. 2014; 148 (discussion 1264–6): 1257-1264Abstract Full Text Full Text PDF PubMed Scopus (94) Google Scholar]. Although rates of surgical site infections are decreasing [38Alasmari F.A. Tleyjeh I.M. Riaz M. et al.Temporal trends in the incidence of surgical site infections in patients undergoing coronary artery bypass graft surgery: a population-based cohort study, 1993 to 2008.Mayo Clin Proc. 2012; 87: 1054-1061Abstract Full Text Full Text PDF PubMed Scopus (14) Google Scholar], mediastinitis and sternal malunion are associated with significant cost, morbidity, and death after CABG [39Speir A.M. Kasirajan V. Barnett S.D. Fonner Jr., E. Additive costs of postoperative complications for isolated coronary artery bypass grafting patients in Virginia.Ann Thorac Surg. 2009; 88 (discussion 45–6): 40-45Abstract Full Text Full Text PDF PubMed Scopus (123) Google Scholar, 40Braxton J.H. Marrin C.A. McGrath P.D. et al.10-year follow-up of patients with and without mediastinitis.Semin Thorac Cardiovasc Surg. 2004; 16: 70-76Abstract Full Text Full Text PDF PubMed Scopus (94) Google Scholar, 41Graf K. 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This increase in sternal mediastinitis may be secondary to a diminution of sternal blood supply after pedicled BITA [24Knobloch K. Lichtenberg A. Pichlmaier M. et al.Microcirculation of the sternum following harvesting of the left internal mammary artery.Thoracic Cardiovasc Surg. 2003; 51: 255-259Crossref PubMed Scopus (46) Google Scholar, 46Takami Y. Tajima K. Masumoto H. Near-infrared spectroscopy for noninvasive evaluation of chest wall ischemia immediately after left internal thoracic artery harvesting.Gen Thorac Cardiovasc Surg. 2008; 56: 281-287Crossref PubMed Scopus (9) Google Scholar, 47Boodhwani M. Lam B.K. Nathan H.J. et al.Skeletonized internal thoracic artery harvest reduces pain and dysesthesia and improves sternal perfusion after coronary artery bypass surgery: a randomized, double-blind, within-patient comparison.Circulation. 2006; 114: 766-773Crossref PubMed Scopus (124) Google Scholar, 48Tang G.H. Maganti M. Weisel R.D. Borger M.A. Prevention and management of deep sternal wound infection.Semin Thorac Cardiovasc Surg. 2004; 16: 62-69Abstract Full Text Full Text PDF PubMed Scopus (70) Google Scholar]. Although several investigators have reported an increased risk of sternal wound infections with BITA harvesting [49Pusca S.V. Kilgo P.D. Vega J.D. et al.Propensity-score analysis of early outcomes after bilateral versus single internal thoracic artery grafting.Innovations (Phila). 2008; 3: 19-24Crossref PubMed Scopus (7) Google Scholar, 50Gansera B. Schmidtler F. Gillrath G. et al.Does bilateral ITA grafting increase perioperative complications? Outcome of 4462 patients with bilateral versus 4204 patients with single ITA bypass.Eur J Cardiothorac Surg. 2006; 30: 318-323Crossref PubMed Scopus (58) Google Scholar], others have reported no significant difference in sternal wound complications, particularly after adjustment for other potentially confounding risk factors (such as sex, obesity, COPD and smoking) [51Momin A.U. Deshpande R. Potts J. et al.Incidence of sternal infection in diabetic patients undergoing bilateral internal thoracic artery grafting.Ann Thorac Surg. 2005; 80 (discussion 1772): 1765-1772Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar]. A major confounding factor for sternal wound infections is whether the diagnosis of DM is a risk factor or whether the risk is more closely associated with poor perioperative glycemic control. Although the importance of glycemic control in the perioperative period is well established, most reports classify patients only as having DM without further stratification of the level or effectiveness of glycemic control. Several reports su