NEWS AND VIEWS

Conduits in Coronary Artery Bypass Grafting Faisal G. Bakaeen, MD, FACS,*,†,‡ Marco A. Zenati, MD, MSc, FETCS,§,‖,¶ and Deepak L. Bhatt, MD, MPH, FACC, FAHA, FSCAI, FESC§,‖ Modern cardiac practice in the United States is conservative when it comes to using bilateral internal mammary or radial artery grafts in coronary artery bypass surgery. Here, we examine the evidence regarding using other arterial grafts instead of veins as a complement to left internal mammary artery in surgical revascularization. In addition, we put our report in perspective relative to prevailing practice, professional societal guidelines, and future directions in coronary artery bypass grafting. Semin Thoracic Surg 25:273–279 Published by Elsevier Inc. Keywords arterial conduits, coronary artery bypass grafting, internal mammary artery, radial artery, saphenous vein graft

*Division of Cardiothoracic Surgery, Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas †The Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas ‡Department of Cardiovascular Surgery, The Texas Heart Institute, Houston, Texas §Harvard Medical School, Boston, Massachusetts ‖Brigham and Women’s Hospital, Boston, Massachusetts ¶Cardiothoracic Surgery, VA Boston Healthcare System, Boston, Massachusetts All authors are on the Executive Committee of the REGROUP trial. Dr Bhatt reports the following associations: Advisory Board: Elsevier Practice Update Cardiology, Medscape Cardiology, Regado Biosciences; Board of Directors: Boston VA Research Institute, Society of Cardiovascular Patient Care; Chair: American Heart Association Get With the Guidelines Steering Committee; Honoraria: American College of Cardiology (Editor, Clinical Trials, CardioSource), Belvoir Publications (Editor in Chief, Harvard Heart Letter), Duke Clinical Research Institute (Clinical Trial Steering Committees), Harvard Clinical Research Institute (Clinical Trial Steering Committee), HMP Communications (Editor in Chief, Journal of Invasive Cardiology); Population Health Research Institute (Clinical Trial Steering Committee), Slack Publications (Chief Medical Editor, Cardiology Today’s Intervention), WebMD (CME Steering Committees); Data Monitoring Committees: Duke Clinical Research Institute; Harvard Clinical Research Institute; Mayo Clinic; Population Health Research Institute; Research Grants: Amarin, AstraZeneca, Bristol- Myers Squibb, Eisai, Ethicon, Medtronic, Roche, Sanofi Aventis, The Medicines Company; Unfunded Research: FlowCo, PLx Pharma, Takeda. Dr Zenati has no commercial interests to disclose. Address reprint requests to Faisal G. Bakaeen, MD, FACS, The Michael E. DeBakey Veterans Affairs Medical Center, OCL 112, 2002 Holcombe Blvd, Houston, TX 77030. E-mail: [email protected]

1043-0679/$-see front matter Published by Elsevier Inc. http://dx.doi.org/10.1053/j.semtcvs.2014.01.002

Using left internal mammary artery (LIMA) conduits in coronary artery bypass grafting (CABG) improves survival, which has led to the widespread use of the LIMA by surgeons worldwide. In fact, in situ LIMA-to-left anterior descending (LAD) artery bypass is now an established quality indicator for CABG surgery (Fig. A).1,2 For complex and multifactorial reasons, other arterial grafts, including the right internal mammary artery (IMA), have not been so widely used (Fig. B and C). Here, we examine the evidence regarding using other arterial grafts instead of veins as a complement to LIMA in CABG surgical procedures. END POINTS To begin, it is important to identify and define the outcome measures and their limitations. The most commonly reported outcome measures in studies of CABG conduits are all-cause mortality and graft patency. All-cause mortality is a hard end point that can be reliably measured. Traditionally, graft patency has been a high priority for surgeons but trails behind clinical outcome measures in the eyes of most cardiologists, who see it as a somewhat soft surrogate end point.3 A problem with graft patency as an end point is that there is no universally accepted definition of graft failure. For example, should an atrophied graft or so-called string sign be regarded as patent? How should different degrees of luminal narrowing be categorized, and what cutoffs should be used? In comparing different grafts’ patencies, how does one reliably adjust for the size, runoff, and degree of stenosis of the target coronary vessel? In addition, 273

CONDUITS IN CORONARY ARTERY BYPASS GRAFTING

Figure.

especially in observational studies, patency is typically measured in a minority of patients,4 but even in randomized controlled trials (RCTs), angiographic follow-up rates are less than 80% a year after CABG5-7 and diminish with longer follow-up.7 In addition, much of the patency data from retrospective studies are derived from clinically driven diagnostic studies—a major source of bias. Traditional coronary angiography requires peripheral vascular access (femoral or radial), which incurs a risk of vascular events. Computed tomographic coronary angiography is not free of risks and requires contrast administration. Further complicating matters is the clinical relevance of graft occlusion, which varies with the myocardial territory at risk, the integrity of the remaining grafts, the severity of native coronary stenosis, and the extent of collaterals. Other outcome measures—the composite of major adverse cardiovascular events, various morbidities, and quality of life—are important and (when reported) are worth evaluating. Costs related to conduit choice are difficult to track and quantify and are therefore rarely reported. SAPHENOUS VEIN In modern CABG trials, the 1-year patency rate of saphenous vein grafts (SVGs) exceeds 80%.5,6,8 After an early phase of thrombosis and intimal

274

hyperplasia, atherosclerosis is the most frequent cause of graft failure after 1 year9; the occlusion rate is 1%-2% each year during the second through fifth years after surgery, and 4%-5% occlude each year between 6 and 10 years postoperatively.10 A Veterans Affairs (VA) Cooperative Study showed that 10year patency was 61% for SVGs and 85% for LIMA grafts.11 In addition, SVGs to the LAD had greater patency than SVGs to the right coronary artery (RCA) or circumflex artery. Other predictors of vein-graft failure have been identified. These include baseline parameters (eg, diabetes), perioperative drug regimens, and intraoperative parameters such as on-pump vs off-pump surgery, vein caliber, target coronary runoff, competitive flow, use of single vs multiple anastomoses, anastomotic technique, and operator experience.3 Vein-harvesting and -handling techniques can also affect graft patency. In an RCT, Souza et al12 showed that “no-touch” SVG harvesting with en bloc removal of surrounding tissue resulted in better patency than conventional SVG harvesting. Poor vein quality and conventional harvesting technique were the strongest predictors of vein-graft failure. Improved endothelial integrity and reduced injury, decelerated atherosclerotic processes, intact adventitial collagen layers, increased total area of vasa vasorum, and elevated endothelial nitric oxide synthase expression have been associated with the no-touch technique.13

Seminars in Thoracic and Cardiovascular Surgery  Volume 25, Number 4

CONDUITS IN CORONARY ARTERY BYPASS GRAFTING Endoscopic saphenous vein harvesting (EVH) is used in approximately 80% of CABG procedures in the United States14 but in the minority of cases in Europe.15 Concerns that EVH might reduce graft patency and increase adverse cardiac outcomes reached a tipping point in 2009, after the secondary analysis of the Project of Ex Vivo Vein Graft Engineering via Transfection trial showed that the rate of vein-graft failure was significantly higher in patients who underwent EVH (46.7% vs 38.0%; odds ratio 1.45, 95% CI: 1.20-1.76).16 Additionally, EVH was associated with a significantly higher combined rate of mortality, myocardial infarction, and repeat revascularization 3 years after surgery (20.2% vs 17.4%; adjusted hazard ratio ¼ 1.22, 95% CI: 1.01-1.47). Because of safety concerns regarding EVH, the US Food and Drug Administration issued a request to analyze the Society of Thoracic Surgeons Adult Cardiac Surgery Database for endoscopic and open vein-graft harvesting–related outcomes. In this study, 235,394 Medicare patients who underwent isolated CABG surgery in 934 surgical centers between 2003 and 2008 were examined, with a 3year median follow-up.17 The 3-year mortality was similar for EVH and open vein-graft harvesting patients (13.2% vs 13.4%, respectively), as was a composite of death, myocardial infarction, and revascularization (19.5% vs 19.7%, respectively). As with other procedures, the harvester’s skill and experience are important considerations with regard to the quality of the endoscopically harvested vein and the associated graft patency.18 The long-term effect of EVH on clinical outcomes has never been investigated in an adequately powered RCT with long-term follow-up. A large, multicenter, VA RCT (REGROUP CSP #588 NCT01850082) is underway to investigate the long-term outcomes of EVH vs the nonendoscopic technique. MAMMARY ARTERIES Single The seminal work by Loop et al19 from the Cleveland Clinic ushered in the era of LIMA use in CABG. For more than 2 decades, LIMA-to-LAD grafting has remained the gold standard and the only technical quality indicator in CABG (Fig. A).1,2 The improved survival associated with LIMA use in primary CABG extends to reoperations. At 20 years, LIMA-to-LAD grafting in redo CABG procedures has been associated with a 6% lower absolute mortality risk, a hazard ratio of 0.85, and a number needed to treat of 16 patients.20 Atherosclerosis in IMA

conduits is rare21; graft patency is around 90% 1015 years after CABG.22 Risk factors for occlusion include smoking, female gender, anastomosis to non-LAD territory, and less severe coronary stenosis.

Bilateral In a recent meta-analysis, Weiss et al23 compared bilateral IMA (BIMA) and LIMA outcomes in studies with at least 4 years of follow-up and at least 100 patients in each group. Interestingly, no RCTs qualified, but 27 observational studies with 79,063 patients (19,277 BIMA and 59,786 LIMA) were included. The BIMA group had significantly better long-term survival than the LIMA group (hazard ratio ¼ 0.78; 95% CI: 0.72-0.84; P o 0.00001). The Arterial Revascularisation Trial24 is an RCT of BIMA vs single IMA (SIMA). The primary outcome is 10-year survival. Interim reporting at 1 year described a 1.2% mortality rate for both groups, and the rates of stroke, myocardial infarction, and repeat revascularization were all r2% and similar between both the groups. Sternal wound reconstruction was required in 0.6% of SIMA and 1.9% of BIMA patients (risk ratio ¼ 3.24, 95% CI: 1.546.83). This increased risk of major sternal wound complications is undoubtedly a source of concern for many surgeons and one of the barriers to adopting a BIMA strategy. However, this complication may be minimized by careful patient selection (avoiding BIMA grafts in obese diabetic patients) and harvesting skeletonized rather than pedicled IMAs, thus reducing damage to the sternal microcirculation25,26 and improving wound healing. A Canadian cardiac surgery registry study examined outcomes among 5601 consecutive patients who underwent isolated CABG with BIMA (n = 1038; 19%), SIMA (n = 4029; 72%), or vein-only grafts (n = 534; 10%). With a mean follow-up of 7 years, and after adjustment for baseline clinical and demographic characteristics, BIMA grafting’s association with better survival was not statistically significant (hazard ratio = 0.87; 95% CI: 0.69-1.08; P = 0.2). However, sensitivity analysis suggested that BIMA grafting might be associated with enhanced survival in patients younger than 70 years.27 No such age cut-off was detected in a larger study (8123 SIMA and 2001 BIMA) with longer follow-up. Lytle et al28 compared the survival of 1152 propensity-matched pairs with a mean follow-up of 16.5 years. During the second postoperative decade, BIMA was associated with greater survival than SIMA, and the magnitude of that benefit increased with time. At 20 years, BIMA grafting was predicted to produce a survival advantage of less than 5% in

Seminars in Thoracic and Cardiovascular Surgery  Volume 25, Number 4

275

CONDUITS IN CORONARY ARTERY BYPASS GRAFTING 13% of patients, greater than 10% in 52%, and greater than 15% in 8%. Only 3% of patients had worse survival with BIMA. In general, IMA graft patency is better than SVG patency,11,29 but a large observational study reported that SVGs had better patency when anastomosed to RCAs with less than 70% stenosis.30 Whether BIMA conduits are configured as in situ grafts or by using a T/Y-composite graft appears not to affect graft patency or clinical outcomes.31 Using SIMA inflow, usually from the LIMA, and using the other conduits in a composite configuration enhances the reach of the accessory arterial grafts and avoids aortic manipulation altogether in off-pump CABG. SIMA inflow is not recommended when the LIMA is small or has poor flow, the patient is unstable, or ischemia is ongoing and a large myocardial territory is at risk.32

Radial The radial artery (RA) graft is easily harvested and can reach all coronary territories, making it an attractive option for an arterial conduit. Both the Radial Artery Patency Study7 and the Radial Artery Versus Saphenous Vein Patency33 studies showed RA grafts to have better patency than SVGs on 5-year angiographic follow-up. In contrast, the 1-year results from the largest study to date to compare RA with SVG (conducted by the VA Cooperative Studies Program)5 and the midterm results of the Radial Artery Patency and Clinical Outcomes study34 suggested comparable patency rates between the RA and SVG. In fact, the Radial Artery Patency and Clinical Outcomes study included a free right IMA arm whose patency rate was equivalent to those of the SVG and RA arms. Table 1 summarizes the findings of relevant RCTs that examined both graft patency and clinical outcomes. A recent meta-analysis by Cao et al35 concluded that selected patients with severe, proximal radial

stenosis may have superior angiographic outcomes at midterm. However, RA is associated with a significantly higher incidence of string sign. To date, no study has shown a survival advantage of RA over SVG grafting. Configuring the RA off an IMA or directly from the aorta for inflow affects patency and clinical outcomes differently among observational studies. The “string sign” is more common in radial than SVG grafts and is closely related to the perioperative use of αadrenergic agonists and less-than-severe targetvessel stenosis.36 The VA study reported longer harvest times for the RA than for the SVG but associated both conduits with similar costs and quality of life.37 The RA is routinely harvested from the nondominant arm because of concerns that RA harvesting could adversely affect hand sensory and motor function. Reassuringly, the VA study reported that, 3 and 12 months postoperatively, manual strength and dexterity were not changed by RA harvesting. In addition, pain at the procurement site was not severe and resolved within 12 months.38 Recently, radial access coronary angiography has gained traction among cardiologists. There are concerns that using RAs for angiography access may compromise their patency if used as CABG grafts.39,40

GASTROEPIPLOIC The gastroepiploic artery is rarely used today, although some centers in Asia still use gastroepiploic grafts and continue to report competitive outcomes associated with them.41 Evidence from RCTs and a recent meta-analysis suggests that the saphenous vein has better early (6 month) and midterm (3 year) graft patency than the right gastroepiploic artery when used for RCA revascularization.42 A small RCT showed that the right gastroepiploic

Table 1. Randomized Trials Comparing Radial Artery vs Saphenous Vein Conduits Study

Publication Year*

Subjects (n)

Coronary Angiography Follow-up (n) (Y)

Radial Benefit Clinical Graft Patency

Deb et al,7 RAPS Goldman et al,5 VA study Hayward et al,34 RAPCO Collins et al,33 RSVP

2012 2011

529 733

269 533

7.7 1

No No

Yes No

2010

225

113

5.5

No

No

2008

142

103

5.6

No

Yes

RAPS, Radial Artery Patency Study; RAPCO, Radial Artery Patency and Clinical Outcomes; RSVP, Radial Artery Versus Saphenous Vein Patency. *Year of publication is the publication date corresponding to the follow-up duration indicated.

276

Seminars in Thoracic and Cardiovascular Surgery  Volume 25, Number 4

CONDUITS IN CORONARY ARTERY BYPASS GRAFTING artery had worse early patency than the RA when taken as a composite graft off the LIMA.43 CURRENT GUIDELINES The only Class I recommendation regarding CABG conduits is to use the LIMA to bypass the LAD. Using a second IMA to graft the left circumflex artery or RCA (when critically stenosed and perfusing left ventricular myocardium) to improve the likelihood of survival and to decrease reintervention has a Class IIa (reasonable) recommendation. Using the RA in similar scenarios, or complete arterial revascularization in young patients with few comorbidities, is designated a Class IIb (may be reasonable) recommendation. The only Class III (harmful) recommendation is arterial grafting of an RCA with less than a critical stenosis (o90%).44 None of the evidence that supports the aforementioned recommendations received top-level (A) designation. This is because of the scarcity of RCTs that have been specifically designed or powered to determine whether arterial grafts provide a longterm survival advantage. In contrast to the American guidelines, the European guidelines45 make a Class I recommendation for all-arterial revascularization in patients with a reasonable life expectancy, based on the correlation between arterial graft use and greater event-free long-term survival, reduced risk of recurrent angina or myocardial infarction, and reduced need for reoperation. Evidence was derived entirely from observational studies, yet it was designated as level A. Interestingly, the adoption of LIMA was primarily driven by a large observational study,18 and it appears that multiple observational studies have associated BIMA with a survival advantage. However, in contrast to LIMA, BIMA’s potential survival advantage may manifest late, reaching statistical significance approximately a decade after the index operation. Performing BIMA or all-arterial CABG well requires additional time and skill (skeletonizing IMAs, constructing conduit-to-conduit anastomoses, and getting the graft configurations and lengths right), making it a harder operation to teach than CABG with SVG. In addition, there is no tangible incentive in terms of reimbursement, short-term cost-effectiveness, or initial patient satisfaction. CONTEMPORARY PRACTICE In the United States, IMA use in CABG rose slowly from 31% in 1988 to 91% in 2008,46 and the use of BIMA increased slightly from 3.5% in 1999 to 4.1% in 2009.47 Analysis of the “run-in phase” at the potential Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery sites

between January and March 2004 revealed no differences in graft use between Europe and North America. Rates of total arterial grafting were higher in France (39%), the Netherlands (15%), and Germany (14%) than in the rest of Europe (mean 12%).48 According to a Society of Thoracic Surgeons database study, RA use peaked at 12.3% of all primary CABGs in 2002 and subsequently declined to 5.5% in 2009.47 The medical management and secondary prevention of coronary artery disease have evolved over the years. Routine statin use and antiplatelet therapy, although not extensively evaluated in CABG trials, are believed to improve outcomes and have qualified as quality indicators for CABG.2 A systematic review of literature concluded that after CABG, statins limit the progression of atherosclerosis in native coronary arteries, inhibit the process of SVG disease, and improve vein-graft patency.49 Aspirin therapy has been shown to improve early SVG patency and outcomes.44 In addition, a recent small meta-analysis associated dual antiplatelet therapy with improved SVG patency but not arterial graft patency.50

Comment There is no doubt that modern cardiac practice in the United States is conservative when it comes to using BIMA or RA grafts in CABG, despite growing observational evidence that BIMA may be associated with improved long-term survival and a decreased need for coronary reintervention. The delayed and rather modest potential effects of BIMA on outcomes and the challenges relating to its use are barriers to wider adoption of BIMA grafting. Some surgeons and centers now use BIMA more frequently, but the average surgical practice does not. We believe that there are certain anatomical and clinical scenarios in which BIMA grafting is beneficial. A young patient with disease involving a small LAD and a large branch of a hyperdominant circumflex artery would benefit from BIMA. In contrast, an older patient with a large LAD that wraps around the apex of the heart and supplies a vast territory of myocardium directly or via well-evolved collaterals is unlikely to derive much benefit from BIMA. The evidence favoring RA over SVG is even less rigorous, but RA may be as good as or better than SVG in appropriately selected targets. The role of fractional flow reserve in coronary revascularization is evolving. By more accurately quantifying the physiological significance of a coronary lesion, it is possible that fractional flow reserve may help in selecting CABG targets and minimizing the incidence of competitive flow. This could

Seminars in Thoracic and Cardiovascular Surgery  Volume 25, Number 4

277

CONDUITS IN CORONARY ARTERY BYPASS GRAFTING Table 2. Best Practices and CABG Conduits Conduit choice LIMA to the left anterior descending coronary artery BIMA for younger patients with no significant morbidity and favorable coronary anatomy Avoid arterial grafts if high risk of competitive flow Radial artery as good as or may be better than vein for appropriately selected non-LAD targets Heart team input Conduit harvest No-touch harvesting or minimal trauma to conduit Skeletonize IMAs if harvesting bilaterally Endoscopic vein harvesting only by experienced harvester using “best practice” Conduit assessment Intraoperative graft patency or flow assessment Conduit maintenance Statins and antiplatelet therapy as part of routine coronary artery disease secondary prevention program

translate into improved graft patency and outcomes, but more data are needed to guide future applications of this promising modality.51 Finally, adhering to best practices (Table 2), including using a multidisciplinary heart team approach to treat CABG patients, is strongly advocated a priori. The blanket recommendation of LIMA-to-LAD and all-vein grafts to other coronaries for all comers is somewhat dated. Thoughtful planning and a personalized approach regarding conduit

choice, incorporating discussions with the informed patient, are encouraged. Importantly, we need more RCT data. Longer-term follow-up from the Arterial Revascularisation trial will be critical to guiding evidence-based conduit selection.

ACKNOWLEDGMENT Stephen N. Palmer, PhD, ELS, contributed to the editing of the article.

1. Guru V, Anderson GM, Fremes SE, et al: The after coronary artery bypass surgery: Results identification and development of Canadian from RAPS (Radial Artery Patency Study). J Am coronary artery bypass graft surgery quality Coll Cardiol 60:28-35, 2012 indicators. J Thorac Cardiovasc Surg 130: 8. Desai ND, Cohen EA, Naylor CD, et al: A 1257, 2005 randomized comparison of radial-artery and 2. Shahian DM, Edwards FH, Ferraris VA, et al: saphenous-vein coronary bypass grafts. N Engl Quality measurement in adult cardiac surgery: J Med 351:2302-2309, 2004 Part 1—Conceptual framework and measure 9. Campeau L, Enjalbert M, Lesperance J, et al: selection. Ann Thorac Surg 83:S3-S12, 2007 Atherosclerosis and late closure of aortocoro3. Harskamp RE, Williams JB, Hill RC, et al: nary saphenous vein grafts: Sequential angioSaphenous vein graft failure and clinical outgraphic studies at 2 weeks, 1 year, 5 to 7 years, comes: Toward a surrogate end point in and 10 to 12 years after surgery. Circulation patients following coronary artery bypass surII1-II7 gery?Am Heart J 165:639-643, 2013 10. Bourassa MG, Fisher LD, Campeau L, et al: 4. Sabik III JF, Stockins A, Nowicki ER, et al: Does Long-term fate of bypass grafts: The Coronary location of the second internal thoracic artery Artery Surgery Study (CASS) and Montreal graft influence outcome of coronary artery Heart Institute experiences. Circulation 72: bypass grafting?Circulation 118:S210-S215, V71-V78, 1985 2008 11. Goldman S, Zadina K, Moritz T, et al: Long5. Goldman S, Sethi GK, Holman W, et al: Radial term patency of saphenous vein and left internal artery grafts vs saphenous vein grafts in coromammary artery grafts after coronary artery nary artery bypass surgery: A randomized trial. bypass surgery: Results from a Department of J Am Med Assoc 305:167-174, 2011 Veterans Affairs Cooperative Study. J Am Coll 6. Shroyer AL, Grover FL, Hattler B, et al: OnCardiol 44:2149-2156, 2004 pump versus off-pump coronary-artery bypass 12. Souza DS, Johansson B, Bojo L, et al: Harvesting surgery. N Engl J Med 361:1827-1837, 2009 the saphenous vein with surrounding tissue for 7. Deb S, Cohen EA, Singh SK, et al: Radial artery CABG provides long-term graft patency comand saphenous vein patency more than 5 years parable to the left internal thoracic artery:

278

13.

14.

15.

16.

17.

18.

Results of a randomized longitudinal trial. J Thorac Cardiovasc Surg 132:373-378, 2006 Sepehripour AH, Jarral OA, Shipolini AR, et al: Does a ‘no-touch’ technique result in better vein patency?Interact Cardiovasc Thorac Surg 13: 626-630, 2011 Zenati MA, Shroyer AL, Collins JF, et al: Impact of endoscopic versus open saphenous vein harvest technique on late coronary artery bypass grafting patient outcomes in the ROOBY (Randomized On/Off Bypass) Trial. J Thorac Cardiovasc Surg 141:338-344, 2011 Head SJ, Borgermann J, Osnabrugge RL, et al: Coronary artery bypass grafting: Part 2—Optimizing outcomes and future prospects. Eur Heart J 34:2873-2886, 2013 Lopes RD, Hafley GE, Allen KB, et al: Endoscopic versus open vein-graft harvesting in coronary-artery bypass surgery. N Engl J Med 361:235-244, 2009 Williams JB, Peterson ED, Brennan JM, et al: Association between endoscopic vs open veingraft harvesting and mortality, wound complications, and cardiovascular events in patients undergoing CABG surgery. J Am Med Assoc 308:475-484, 2012 Desai P, Kiani S, Thiruvanthan N, et al: Impact of the learning curve for endoscopic vein

Seminars in Thoracic and Cardiovascular Surgery  Volume 25, Number 4

CONDUITS IN CORONARY ARTERY BYPASS GRAFTING

19.

20.

21.

22.

23.

24.

25.

26.

27.

28.

29.

harvest on conduit quality and early graft patency. Ann Thorac Surg, 91:1385-1391, 2011 [discussion 1391-1392]. Loop FD, Lytle BW, Cosgrove DM, et al: Influence of the internal-mammary-artery graft on 10-year survival and other cardiac events. N Engl J Med 314:1-6, 1986 Sabik III JF, Raza S, Blackstone EH, et al: Value of internal thoracic artery grafting to the left anterior descending coronary artery at coronary reoperation. J Am Coll Cardiol 61: 302-310, 2013 Sisto T, Isola J: Incidence of atherosclerosis in the internal mammary artery. Ann Thorac Surg 47:884-886, 1989 Sabik III JF, Lytle BW, Blackstone EH, et al: Does competitive flow reduce internal thoracic artery graft patency?Ann Thorac Surg 76: 1490-1496, 2003 [discussion 1497] Weiss AJ, Zhao S, Tian DH, et al: A metaanalysis comparing bilateral internal mammary artery with left internal mammary artery for coronary artery bypass grafting. Ann Cardiothorac Surg 2:390-400, 2013 Taggart DP, Altman DG, Gray AM, et al: Randomized trial to compare bilateral vs. single internal mammary coronary artery bypass grafting: 1-year results of the Arterial Revascularisation Trial (ART). Eur Heart J 31: 2470-2481, 2010 Boodhwani M, Lam BK, Nathan HJ, et al: Skeletonized internal thoracic artery harvest reduces pain and dysesthesia and improves sternal perfusion after coronary artery bypass surgery: A randomized, double-blind, withinpatient comparison. Circulation 114: 766-773, 2006 Kamiya H, Akhyari P, Martens A, et al: Sternal microcirculation after skeletonized versus pedicled harvesting of the internal thoracic artery: A randomized study. J Thorac Cardiovasc Surg 135:32-37, 2008 Kieser TM, Lewin AM, Graham MM, et al: Outcomes associated with bilateral internal thoracic artery grafting: The importance of age. Ann Thorac Surg 92:1269-1275, 2011 [discussion 1275-1276] Lytle BW, Blackstone EH, Sabik JF, et al: The effect of bilateral internal thoracic artery grafting on survival during 20 postoperative years. Ann Thorac Surg 78:2005-2012, 2004 [discussion 2012-2014] Fitzgibbon GM, Kafka HP, Leach AJ, et al: Coronary bypass graft fate and patient outcome: Angiographic follow-up of 5,065 grafts related to survival and reoperation in 1,388

30.

31.

32. 33.

34.

35.

36.

37.

38.

39.

40.

41.

patients during 25 years. J Am Coll Cardiol 28: 616-626, 1996 Sabik III JF, Lytle BW, Blackstone EH, et al: Comparison of saphenous vein and internal thoracic artery graft patency by coronary system. Ann Thorac Surg 79:544-551, 2005 [discussion 544-551] Hwang HY, Kim JS, Cho KR, et al: Bilateral internal thoracic artery in situ versus Ycomposite graftings: Five-year angiographic patency and long-term clinical outcomes. Ann Thorac Surg 92:579-585, 2011 [discussion 585-586] Bakaeen FG: Invited commentary. Ann Thorac Surg 95:853, 2013 Collins P, Webb CM, Chong CF, et al: Radial artery versus saphenous vein patency randomized trial: Five-year angiographic follow-up. Circulation 117:2859-2864, 2008 Hayward PA, Gordon IR, Hare DL, et al: Comparable patencies of the radial artery and right internal thoracic artery or saphenous vein beyond 5 years: Results from the Radial Artery Patency and Clinical Outcomes trial. J Thorac Cardiovasc Surg 139:60-65, 2010 [discussion 65-67] Cao C, Ang SC, Wolak K, et al: A meta-analysis of randomized controlled trials on mid-term angiographic outcomes for radial artery versus saphenous vein in coronary artery bypass graft surgery. Ann Cardiothorac Surg 2: 401-407, 2013 Miwa S, Desai N, Koyama T, et al: Radial artery angiographic string sign: Clinical consequences and the role of pharmacologic therapy. Ann Thorac Surg 81:112-118, 2006 [discussion 119] Wagner TH, Sethi G, Holman W, et al: Costs and quality of life associated with radial artery and saphenous vein cardiac bypass surgery: Results from a Veterans Affairs multisite trial. Am J Surg 202:532-535, 2011 Holman WL, Davies JE, Lin JY, et al: Consequences of radial artery harvest: Results of a prospective, randomized, multicenter trial. JAMA Surg 148:1020-1023, 2013 Kamiya H, Ushijima T, Kanamori T, et al: Use of the radial artery graft after transradial catheterization: Is it suitable as a bypass conduit?Ann Thorac Surg 76:1505-1509, 2003 Buxton BF, Galvin SD: The history of arterial revascularization: From Kolesov to Tector and beyond. Ann Cardiothorac Surg 2: 419-426, 2013 Suma H, Tanabe H, Takahashi A, et al: Twenty years experience with the gastroepiploic artery graft for CABG. Circulation 116:I188-I191, 2007

Seminars in Thoracic and Cardiovascular Surgery  Volume 25, Number 4

42. Mukherjee D, Cheriyan J, Kourliouros A, et al: How does the right gastroepiploic artery compare with the saphenous vein for revascularization of the right coronary artery? Interact Cardiovasc Thorac Surg 15: 888-892, 2012 43. Santos GG, Stolf NA, Moreira LF, et al: Randomized comparative study of radial artery and right gastroepiploic artery in composite arterial graft for CABG. Eur J Cardiothorac Surg 21:1009-1014, 2002 44. Hillis LD, Smith PK, Anderson JL, et al: 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. J Am Coll Cardiol 58:e123-e210, 2011 45. Task Force on Myocardial Revascularization of the European Society of Cardiology, the European Association for Cardio-Thoracic Surgery, European Association for Percutaneous Cardiovascular Interventions, et al. Guidelines on myocardial revascularization. Eur Heart J 31: 2501-2555, 2010 46. Hlatky MA, Boothroyd DB, Reitz BA, et al: Adoption and effectiveness of internal mammary artery grafting in coronary artery bypass surgery among Medicare beneficiaries. J Am Coll Cardiol (in press). 47. ElBardissi AW, Aranki SF, Sheng S, et al: Trends in isolated coronary artery bypass grafting: An analysis of the Society of Thoracic Surgeons adult cardiac surgery database. J Thorac Cardiovasc Surg 143:273-281, 2012 48. Kappetein AP, Dawkins KD, Mohr FW, et al: Current percutaneous coronary intervention and coronary artery bypass grafting practices for three-vessel and left main coronary artery disease. Insights from the SYNTAX run-in phase. Eur J Cardiothorac Surg 29: 486-491, 2006 49. Kulik A, Ruel M: Lipid-lowering therapy and coronary artery bypass graft surgery: What are the benefits? Curr Opin Cardiol 26:508-517, 2011 50. Nocerino AG, Achenbach S, Taylor AJ: Metaanalysis of effect of single versus dual antiplatelet therapy on early patency of bypass conduits after coronary artery bypass grafting. Am J Cardiol 112:1576-1579, 2013 51. Lazar HL: Fractional flow-guided coronary artery bypass grafting: A word of caution. Circulation 128:1393-1395, 2013

279

Conduits in coronary artery bypass grafting.

Modern cardiac practice in the United States is conservative when it comes to using bilateral internal mammary or radial artery grafts in coronary art...
3MB Sizes 0 Downloads 4 Views