Comparison of Drug-Eluting Stents With Bare-Metal Stents for PCI of Saphenous Vein Graft Lesions: Systematic Review and Meta-Analysis
Abstract: Background. The superiority of drug-eluting stent (DES) implantation over bare-metal stent (BMS) implantation in saphenous vein graft (SVG) lesions is controversial, with significant heterogeneity demonstrated in the literature. Methods. A study search was conducted from January 2003 to October 2015, and identified four randomized controlled trials (RCTs) and 35 observational studies comparing DES vs BMS in SVG interventions. Clinical endpoint data were abstracted and analyzed by combining the odds ratios (ORs) of individual studies into a pooled OR using a random-effects model. Results. The meta-analysis included 39,213 patients in the DES group and 26,461 patients in the BMS group. Patients who underwent percutaneous coronary intervention with DES had lower major adverse cardiovascular event (MACE) rate (OR, 0.63; 95% confidence interval [CI], 0.54-0.74; P<.001), lower all-cause mortality rate (OR, 0.76; 95% CI, 0.69-0.84; P<.001), lower target-vessel revascularization (TVR) rate (OR, 0.70; 95% CI, 0.57-0.86; P<.001), and lower target-lesion revascularization (TLR) rate (OR, 0.64; 95% CI, 0.50-0.84; P<.01), with no difference in stent thrombosis (OR, 0.90; 95% CI, 0.61-1.32; P=.58). There was no significant reduction in myocardial infarction (MI) in the DES group compared with the BMS group (OR, 0.87; 95% CI, 0.73-1.04; P=.13). Benefits were sustained at long-term follow-up of 36 months without an increased risk of early and/or late stent thrombosis. The observed benefit for MACE was only seen in observational studies (OR, 0.63; 95% CI, 0.53-0.75; P<.001) with no benefit in RCTs (OR, 0.53; 95% CI, 0.20-1.40; P=.20). Conclusions. The results suggest that patients with DES in comparison with BMS implantation for PCI to SVG lesions had lower MACE, all-cause mortality, and TVR rates, without a significant reduction in MI and TLR.
J INVASIVE CARDIOL 2016;28(12):E139-E169. Epub 2016 November 15.
Key words: stenting, drug-eluting stent, DES, bare-metal stent, BMS
Percutaneous coronary intervention (PCI) of saphenous vein graft (SVG) lesions comprises up to 15% of all coronary artery interventions.1,2 Approximately 50% of all vein grafts develop significant stenosis or complete occlusion within 10 years of implantation.1,3 Given the high-risk nature of repeat coronary artery bypass graft (CABG) surgery in these patients, PCI is preferred to restore vessel patency and improve symptoms.4,5 Drug-eluting stent (DES) implantation has demonstrated superiority to conventional balloon angioplasty and bare-metal stent (BMS) implantation for the treatment of de novo in-stent restenosis in native coronary artery lesions.6 Despite the wealth of evidence, the superiority of DES to BMS implantation in SVG lesions has shown significant heterogeneity in clinical outcomes.
The DELAYED-RRISC (Death and Events at Long-term follow-up Analysis: Extended Duration of the Reduction of Restenosis In Saphenous vein grafts with Cypher stent) randomized trial of 75 patients with sirolimus DES vs BMS showed a trend toward increased repeat revascularization and increased mortality in the DES group at 6 months.7 In contrast, the SOS (Stenting of Saphenous Vein Grafts) randomized trial of 80 patients demonstrated that patients receiving pac-litaxel DES had less myocardial infarction (MI), target-lesion revascularization (TLR), and target-vessel revascularization (TVR), and a trend toward decreased stent thrombosis (ST) compared with those receiving BMS.8 Since these trials, observational studies and registry data have been published with a focus on long-term clinical endpoints.9 Therefore, we performed an updated meta-analysis of randomized controlled trials (RCTs) and observational studies to compare the efficacy and safety of DES vs BMS to treat SVG lesions.
Methods
Study selection. A systematic search was conducted to retrieve RCTs and observational studies that investigated the efficacy and safety of DES vs BMS for the treatment of SVG lesions. The study search was conducted through PubMed and EMBASE for studies from January 2003 (the advent of DES) to October 2015. The following keywords were used: “saphenous vein graft,” “drug-eluting stent,” and “bare-metal stent.” The related articles and reference lists of studies were also reviewed to identify additional relevant publications by manual search. An electronic search of abstracts available online was also reviewed from the annual congresses of the Canadian Cardiovascular Congress, European Society of Cardiology, American College of Cardiology, and the American Heart Association.
Inclusion criteria for the studies included the following: (1) RCTs and observational studies; (2) patients with de novo SVG lesions amenable to PCI; (3) patients eligible for both DES and BMS implantation; and (4) studies published in the English language. Eligibility assessment and data extraction were carried out independently by two investigators (WM and ME) with discrepancies resolved by a third investigator (SG).
Study outcomes. The primary outcome was major adverse cardiovascular event (MACE) rate. Secondary outcomes of interest included all-cause mortality, MI, TVR, TLR, and ST. The definitions of the primary outcome of MACE and the secondary outcomes of MI, TLR, TVR, and stent thrombosis according to each study are included in Table 1. When MACE rate was not specifically reported, individual study endpoints were combined for a pooled estimate. We also performed a stratified analysis of endpoints according to follow-up duration post PCI (≤12 months, between 12 to 36 months, and ≥36 months). We performed a separate threshold analysis to assess the use of embolic protection devices (EPDs) and the relationship with MACE.
Data extraction and study quality. The included studies were independently reviewed for eligibility and quality assessment, and abstracted by two evaluators (WM and ME). The quality assessment was done using a modified Newcastle-Ottawa Quality Assessment Scale for observational studies, and the Jadad score for randomized studies (Supplementary Table 2; see .Pdf). Any discrepancies in data abstraction and study inclusion were resolved by consultation with a third author (SG).
Statistical analysis. The meta-analysis was conducted by combining the odds ratios (ORs) of individual studies into a pooled OR using a random-effects model. Summary ORs were calculated and reported with 95% confidence intervals (CIs). A P-value <.05 was deemed indicative of a statistically significant difference. We tested for heterogeneity using the Chi2 test and the I2 test. Funnel plots were constructed to assess for publication bias. The analyses were performed with RevMan 5.1 software (Review Manager [RevMan] version 5.1. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration; 2011).
Results
Study selection. Figure 1 outlines the search strategy, which yielded 429 results. Of these, 63 studies were duplicate studies, which were removed. A total of 366 studies were screened, 281 were excluded upon review of the title and abstract, with 46 studies excluded after careful review of the full text. Of these studies, 28 did not include the outcome of interest, 5 were missing a cohort arm for comparison,10-14 3 included arterial grafts in the study population,15-17 2 were post hoc analyses,18,19 2 were abstracts,20,21 and 3 included the same study population as prior studies.22-24 Three papers were published for the Stenting of Saphenous Vein Grafts (SOS) trial;8,25,26 only the study with the longest post-PCI follow-up was included in the analysis.26 Thus, 39 studies with 65,674 patients were eligible for inclusion in the systematic review.
Characteristics of included studies. Four randomized trials7,26-28 and 35 observational studies9,13,29-61 were included, with patients enrolled from 2005 to 2015. There was no evidence of publication bias (Figure 2). As detailed in Table 1, all studies included patients with first-generation DES; 5 studies included patients with exclusively paclitaxel-eluting stents,8,25,26,32,35 4 studies included exclusively sirolimus-eluting stents,7,31,33,34 7 studies did not specify the type of DES,9,51,52,57,58,61 and 26 studies included patients with both paclitaxel-eluting and sirolimus-eluting stents. Five studies included patients with second-generation DESs (everolimus-eluting and zotarolimus-eluting)45,54,55,59,60 as well as first-generation DESs. All patients were treated with lifelong aspirin (81 to 325 mg). Clopidogrel was prescribed for a minimum of 1 month after BMS implantation in all studies, and a minimum of 3-6 months after DES implantation, except in the DELAYED-RISCC study,7 where clopidogrel was administered for at least 2 months in all patients.
Patient and procedure characteristics. Characteristics of eligible studies, patient demographics, and procedural features are outlined in Table 1 and Table 2. Patients had a mean age of 70 years, were less likely to be female (24%), and had multiple cardiovascular risk factors including hypertension (75%), hyperlipidemia (75%), diabetes (38%), and a history of smoking (22%). The mean SVG age was 10.7 years, with an average of 1.5 stents placed per patient. Approximately 60% of all patients underwent PCI for acute coronary syndrome (ACS).
Outcomes. Table 3 summarizes the results for all outcomes. For the primary outcome, patients who underwent PCI with a DES had fewer MACE than patients in the BMS group (Figure 3) (OR, 0.63; 95% CI, 0.54-0.74; P<.001). Patients who underwent PCI with DES had less all-cause mortality (Figure 4) (OR, 0.76; 95% CI, 0.69-0.84; P<.001), TLR (Figure 5) (OR, 0.64; 95% CI, 0.50-0.84; P<.01), and TVR (Figure 6) (OR, 0.70; 95% CI, 0.57-0.86; P<.001), without a significant difference in MI (Figure 7) (OR, 0.87; 95% CI, 0.73-1.04; P=.13) or stent thrombosis (Figure 8) (OR, 0.90; 95% CI, 0.61-1.32; P=.58). A sensitivity analysis was performed with the exclusion of the largest study by Brennan et al,61 and the results remained consistent for MACE (OR, 0.61; 95% CI, 0.52-0.73; P<.001), all-cause mortality (OR, 0.76; 95% CI, 0.67-0.86; P<.001), TLR (OR, 0.64; 95% CI, 0.50-0.84; P<.01), TVR (OR, 0.69; 95% CI, 0.58-0.82; P<.001), MI (OR, 0.86; 95% CI, 0.70-1.05; P=.13), and stent thrombosis (OR, 0.90; 95% CI, 0.61-1.32; P=.58).
When analyzed according to the type of study, the benefit for MACE was only seen in observational studies (OR, 0.63; 95% CI, 0.53-0.75; P<.001), with no benefit in RCTs (OR, 0.53; 95% CI, 0.20-1.40; P=.20). Similarly, a benefit for all-cause mortality was only seen in observational studies (OR, 0.75; 95% CI, 0.72-0.78; P<.001), with no benefit in RCTs (OR, 1.45; 95% CI, 0.44-4.84; P=.54). A sensitivity analysis was performed with the exclusion of the DELAYED-RRISC trial,7 showing a significant reduction of MACE in the DES group for the remaining RCTs (OR, 0.34; 95% CI, 0.13-0.90; P=.03).
A stratified analysis of events according to the duration of follow-up post PCI showed that at 36 months of follow-up in those with DES, there were lower MACE (OR, 0.79; 95% CI, 0.64-0.97; P=.03), and all-cause mortality rates (OR, 0.76; 95% CI, 0.73-0.79; P<.001). The initial reduction of MI observed <12 months post PCI in the DES group (OR, 0.72; 95% CI, 0.57-0.92; P<.01) was not consistent over time, without a significant benefit observed in studies reporting outcomes ≥36 months (OR, 0.82; 95% CI, 0.59-1.12; P=.21). This was similar for TVR (OR, 0.71; 95% CI, 0.49-1.02; P=.07) and TLR (OR, 0.77; 95% CI, 0.27-2.22; P=.63), without an observed benefit at ≥36 months. There was no significant increase in ST in the DES group for all time points of follow-up post PCI (<12 months post PCI: OR, 0.89; 95% CI, 0.45-1.74 [P=.11]; 12-36 months post PCI: OR, 0.58, 95% CI, 0.30-1.13 [P=.11]; ≥36 months post PCI: OR, 0.75; 95% CI, 0.35-1.61 [P=.46]).
To address the role of EPD use, we performed a threshold analysis to compare MACE based on the percentage of EPD use in each group. This was performed with the exclusion of the largest study by Brennan et al.61 Patients in the DES group had lower MACE rate regardless of EPD use (<20%: OR, 0.47 [P<.001]; <30%: OR, 0.72 [P<.001]; <40%: OR, 0.69 [P<.001]). Further specific details for each study included in the meta-analysis are available in Supplementary Tables 1-4 and Figures 1-6, in .Pdf.
Discussion
The results of this meta-analysis show that in patients who underwent PCI to SVG lesions, DES implantation in comparison with BMS had lower MACE, all-cause mortality, TLR, and TVR rates. Patients who underwent implantation with DES did not have an increased risk of early and/or late ST compared with BMS. The benefit for MACE and mortality appears to be driven by observational studies, without benefit seen in RCTs. There was no reduction in MI and TLR at long-term follow-up in patients who underwent DES implantation.
There are several strengths to this updated meta-analysis. Our study is the largest reported meta-analysis with the addition of recent long-term data from the original trials that compared DES vs BMS stent implantation for SVG lesions. We provide the first pooled analysis of long-term efficacy and safety of DES vs BMS, which allows us to assess the sustained benefit of reduction in events. Our analysis is the first to demonstrate the benefit of DES implantation in SVG-PCI regardless of the percentage of EPD use.
Several discrepancies were noted between RCTs and observational studies — most notably, the increased all-cause mortality seen in RCTs in patients who underwent DES implantation. The largest increase in all-cause mortality was seen in the DELAYED-RRISC trial, a small trial of 75 patients with a 30-fold increase in all-cause mortality. There are several reasons why such a large discrepancy may have been seen in this RCT. This trial did not have adequate power to identify true effects on mortality, and the results were not replicated in any other RCT or observational study. The observed increase in mortality in this trial was due to non-cardiac deaths. Based upon this evidence, we do not suggest that patients who underwent DES implantation had an increased risk of cardiovascular mortality. Furthermore, the recommended duration of dual-antiplatelet therapy (DAPT) in both groups in this study was a minimum of 2 months, with additional therapy left to the treating physician. At 6 months, there was no significant difference between the two groups, with half of patients in both groups still taking DAPT. The probability of death due to a premature termination of DAPT, while possible, remains unclear.
The reduction in MACE seen only in observational studies may also be attributed to selection bias in cohort studies. In the large studies that showed a mortality benefit with DES,46,54,55,58 BMS implantation was utilized more in acute settings such as ST-elevation MI, which may overestimate the benefit of DES use. Patients in the DES group also received DAPT for a longer duration, which may have also offered additional long-term benefit. To further assess this heterogeneity, the DELAYED-RRISC trial was excluded through sensitivity analysis. The results of this sensitivity analysis were reassuring, as RCTs still showed a significant reduction in MACE in the DES group, thus supporting the results of observational studies.
Several studies have attempted to address the late catch-up phenomenon, which describes an early benefit of DES implantation that becomes insignificant over time due to delayed and progressive lumen loss resulting in long-term events.7,46 Our analysis of study endpoints according to the duration of follow-up post PCI (<12 months post PCI, 12-36 months post PCI, and ≥36 months post PCI) showed that the early benefit of DES implantation for MACE and all-cause mortality remained consistent even at ≥36 months follow-up post PCI. However, there was no long-term benefit for MI, TVR, and TLR. Therefore, this late catch-up phenomenon may exist for these outcomes, which weakens the suggested benefit of DES implantation in the long-term.
The mechanism of in-stent restenosis in SVG differs from that of native coronary arteries as there is prolonged intimal hyperplasia, accelerated atherosclerosis, delayed endothelialization, and thrombotic tendency.61,62 For these reasons, DES implantation is thought to reduce high rates of repeat revascularization. First-generation DES implantation has been shown to increase late ST in PCI to native coronary artery vessels with increased mortality.62,63 In our stratified analysis of events, we did not observe an increased risk of early and/or late ST, MI, or TLR in DES patients. Our analysis suggests first-generation DES use in PCI to SVG lesions is safe at early and long-term follow-up.
Study limitations. There was an inconsistency among the studies’ definitions of MACE, because some studies did not include TLR or TVR in the reported composite outcome. In addition, only 4 studies9,26,51,54 reported follow-up durations of ≥36 months for TLR with a total of 1131 patients, which is a significantly smaller group of patients in comparison with other endpoints assessed for the same follow-up duration. This may result in a selection bias and underestimation of the overall treatment effect. The benefit of first-generation DES implantation is obsolete, as current practice utilizes almost exclusively second-generation DES implantation. In our analysis, patients included in observational studies and RCTs had first-generation DESs; the results of this meta-analysis may not be generalizable to the newer generation of DESs. The study by Aggarwal and colleagues60 is the only RCT that included patients who underwent PCI with second-generation DES implantation. In this study, patients receiving second-generation DESs had lower mortality than those with first-generation DESs; both had significant mortality benefit over BMS. A recent study also concluded that first-generation and second-generation DESs had similar long-term outcomes in vein grafts.64
Conclusion
The results of our meta-analysis suggest that patients with DES for PCI to SVG lesions had lower MACE, all-cause mortality, and TVR rates, without a significant reduction in MI and TLR rates vs BMS implantation. Despite the use of first-generation DESs with a higher risk profile than current second-generation DESs, these benefits are sustained at long-term follow-up with no increased risk of early and/or late ST, independent of EPD use. These results suggest that DES use in SVG-PCI patients is safe, effective, and consistent.
References
1. Nwasokwa ON. Coronary artery bypass graft disease. Ann Intern Med. 1995;123:528-545.
2. Eagle KA, Guyton RA, Davidoff R, et al. ACC/AHA 2004 guideline update for coronary artery bypass graft surgery: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee to Update the 1999 Guidelines for Coronary Artery Bypass Graft Surgery). Circulation. 2004;110:e340-e437.
3. Goldman 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;44:2149-2156.
4. Weintraub WS, Jones EL, Morris DC, King SB 3rd, Guyton RA, Craver JM. Outcome of reoperative coronary bypass surgery versus coronary angioplasty after previous bypass surgery. Circulation. 1997;95:868-877.
5. Savage MP, Douglas JS Jr, Fischman DL, et al. Stent placement compared with balloon angioplasty for obstructed coronary bypass grafts. Saphenous Vein De Novo Trial Investigators. N Engl J Med. 1997;337:740-747.
6. Morice MC, Serruys PW, Sousa JE, et al. A randomized comparison of a sirolimus-eluting stent with a standard stent for coronary revascularization. N Engl J Med. 2002;346:1773-1780.
7. Vermeersch P, Agostoni P, Verheye S, et al. Increased late mortality after sirolimus-eluting stents versus bare-metal stents in diseased saphenous vein grafts: results from the randomized DELAYED-RRISC trial. J Am Coll Cardiol. 2007;50:261-267.
8. Brilakis ES, Lichtenwalter C, de Lemos JA, et al. A randomized controlled trial of a paclitaxel-eluting stent versus a similar bare-metal stent in saphenous vein graft lesions the SOS (Stenting of Saphenous Vein Grafts) trial. J Am Coll Cardiol. 2009;53:919-928.
9. Hougaard M, Thayssen P, Kaltoft A, et al. Long-term outcome following percutaneous coronary intervention with drug-eluting stents compared with bare-metal stents in saphenous vein graft lesions: from Western Denmark Heart Registry. Catheter Cardiovasc Interv. 2014;83:1035-1042.
10. Pendyala LK, Loh JP, Kitabata H, et al. The impact of diabetes mellitus on long-term clinical outcomes after percutaneous coronary saphenous vein graft interventions in the drug-eluting stent era. J Interv Cardiol. 2014;27:391-398.
11. Wessely R, Marzocchi A, Schwacke H, et al. Long-term follow-up of coronary venous bypass graft lesions treated with a new generation drug-eluting stent with bioabsorbable polymer. J Interv Cardiol. 2013;26:425-433.
12. Taniwaki M, Raber L, Magro M, et al. Long-term comparison of everolimus-eluting stents with sirolimus- and paclitaxel-eluting stents for percutaneous coronary intervention of saphenous vein grafts. EuroIntervention. 2014;9:1432-1440.
13. Ko DT, Guo H, Wijeysundera HC, et al. Long-term safety and effectiveness of drug-eluting stents for the treatment of saphenous vein grafts disease: a population-based study. JACC Cardiovasc Interv. 2011;4:965-973.
14. Rodes-Cabau J, Bertrand OF, Larose E, et al. Five-year follow-up of the plaque sealing with paclitaxel-eluting stents vs medical therapy for the treatment of intermediate nonobstructive saphenous vein graft lesions (VELETI) trial. Can J Cardiol. 2014;30:138-145.
15. Harskamp RE, Kuijt WJ, Damman P, et al. Percutaneous coronary intervention for acute coronary syndrome due to graft failure: use of bare-metal and drug-eluting stents and subsequent long-term clinical outcome. Catheter Cardiovasc Interv. 2014;83:203-209.
16. Voudris V, Kalianos C, Patsilinakos S, et al. Effectiveness of drug-eluting stents in the treatment of bypass graft lesions. Eur Heart J. 2006;S27:925.
17. Leal S, Campante Teles R, Cale R, et al. Percutaneous revascularization strategies in saphenous vein graft lesions: long-term results. Rev Port Cardiol. Jan 2012;31:11-18.
18. Michael TT, Abdel-Karim AR, Papayannis A, et al. Recurrent cardiovascular events with paclitaxel-eluting versus bare-metal stents in saphenous vein graft lesions: insights from the SOS (Stenting of Saphenous Vein Grafts) trial. J Invasive Cardiol. 2011;23:216-219.
19. Michael TT, Badhey N, Banerjee S, Brilakis ES. Comparison of characteristics and outcomes of patients undergoing saphenous vein graft stenting who were or were not enrolled in the stenting of saphenous vein grafts randomized controlled trial. J Invest Med. 2011;59:259-266.
20. Bair TL, Muhlestein JB, May HT, et al. Use of drug-eluting stents in saphenous vein graft lesions. J Am Coll Cardiol. 2008;51(S1):A381.
21. Kanei Y, Sharma J, Diwan R, Nakra NC, Lakhanpal G, Fox JT. Long-term outcome of drug-eluting stents in saphenous vein graft lesions. Cardiovasc Revasc Med. 2008;9:192-216.
22. Abdel-Karim AR, Banerjee S, Brilakis ES. Percutaneous intervention of acutely occluded saphenous vein grafts: contemporary techniques and outcomes. J Invasive Cardiol. Jun 2010;22(6):253-257.
23. Wilson BH HA, Cedarholm JD, Elliot CM, Harber RH, Kowalchuk GT, Rinaldi MS, Simonton CAIII. Drug-eluting stents are no better than bare metal in vein graft: Results from the strategy transcatheter evaluation of new therapies (STENT) group. J Am Coll Cardiol. 2007;41B:2802–2803.
24. Nair SB, Chacko S, Clarke B, et al. Comparison of drug eluting stents and bare metal stents in saphenous vein graft PCI; a single-centre experience. Eur Heart J. 2009:254.
25. Brilakis ES, Lichtenwalter C, Abdel-Karim AR, et al. Continued benefit from paclitaxel-eluting compared with bare-metal stent implantation in saphenous vein graft lesions during long-term follow-up of the SOS (Stenting of Saphenous Vein Grafts) trial. JACC Cardiovasc Interv. 2011;4:176-182.
26. Sosa A, Chao H, Guerra A, et al. Paclitaxel-eluting vs bare metal stent implantation in saphenous vein graft lesions: very long-term follow-up of the SOS (Stenting of Saphenous vein grafts) trial. Int J Cardiol. 2015;186:261-263.
27. Jeger RV, Schneiter S, Kaiser C, et al. Drug-eluting stents compared with bare metal stents improve late outcome after saphenous vein graft but not after large native vessel interventions. Cardiology. 2009;112:49-55.
28. Mehilli J, Pache J, Abdel-Wahab M, et al. Drug-eluting versus bare-metal stents in saphenous vein graft lesions (ISAR-CABG): a randomised controlled superiority trial. Lancet. 2011;378:1071-1078.
29. Ge L, Iakovou I, Sangiorgi GM, et al. Treatment of saphenous vein graft lesions with drug-eluting stents: immediate and midterm outcome. J Am Coll Cardiol. 2005;45:989-994.
30. Lee MS, Shah AP, Aragon J, et al. Drug-eluting stenting is superior to bare metal stenting in saphenous vein grafts. Catheter Cardiovasc Interv. 2005;66:507-511.
31. Chu WW, Rha SW, Kuchulakanti PK, et al. Efficacy of sirolimus-eluting stents compared with bare metal stents for saphenous vein graft intervention. Am J Cardiol. 2006;97:34-37.
32. Hoffmann R, Pohl T, Koster R, Blindt R, Boeckstegers P, Heitzer T. Implantation of paclitaxel-eluting stents in saphenous vein grafts: clinical and angiographic follow-up results from a multicentre study. Heart. 2007;93:331-334.
33. Minutello RM, Bhagan S, Sharma A, et al. Long-term clinical benefit of sirolimus-eluting stents compared to bare metal stents in the treatment of saphenous vein graft disease. J Interv Cardiol. 2007;20:458-465.
34. Ellis SG, Kandzari D, Kereiakes DJ, et al. Utility of sirolimus-eluting Cypher stents to reduce 12-month target vessel revascularization in saphenous vein graft stenoses: results of a multicenter 350-patient case-control study. J Invasive Cardiol. 2007;19:404-409.
35. Wohrle J, Nusser T, Kestler HA, Kochs M, Hombach V. Comparison of the slow-release polymer-based paclitaxel-eluting Taxus-Express stent with the bare-metal Express stent for saphenous vein graft interventions. Clin Res Cardiol. 2007;96:70-76.
36. Okabe T, Lindsay J, Buch AN, et al. Drug-eluting stents versus bare metal stents for narrowing in saphenous vein grafts. Am J Cardiol. 2008;102:530-534.
37. Bansal D, Muppidi R, Singla S, et al. Percutaneous intervention on the saphenous vein bypass grafts — long-term outcomes. Catheter Cardiovasc Interv. 2008;71:58-61.
38. Applegate RJ, Sacrinty M, Kutcher M, Santos R, Gandhi S, Little W. Late outcomes of drug-eluting versus bare metal stents in saphenous vein grafts: Propensity score analysis. Catheter Cardiovasc Interv. 2008;72:7-12.
39. Assali A, Raz Y, Vaknin-Assa H, et al. Beneficial 2-years results of drug-eluting stents in saphenous vein graft lesions. EuroIntervention. 2008;4:108-114.
40. Gioia G, Benassi A, Mohendra R, Chowdhury K, Masood I, Matthai W. Lack of clinical long-term benefit with the use of a drug eluting stent compared to use of a bare metal stent in saphenous vein grafts. Catheter Cardiovasc Interv. 2008;72:13-20.
41. Kaplan S, Barlis P, Kiris A, Dimopoulos K, Celik S, Di Mario C. Immediate procedural and long-term clinical outcomes following drug-eluting stent implantation to ostial saphenous vein graft lesions. Acute Card Care. 2008;10:88-92.
42. Vignali L, Saia F, Manari A, et al. Long-term outcomes with drug-eluting stents versus bare metal stents in the treatment of saphenous vein graft disease (results from the REgistro Regionale AngiopLastiche Emilia-Romagna registry). Am J Cardiol. 2008;101:947-952.
43. Ramana RK, Ronan A, Cohoon K, et al. Long-term clinical outcomes of real-world experience using sirolimus-eluting stents in saphenous vein graft disease. Catheter Cardiovasc Interv. 2008;71:886-893.
44. van Twisk PH, Daemen J, Kukreja N, van Domburg RT, Serruys PW. Four-year safety and efficacy of the unrestricted use of sirolimus- and paclitaxel-eluting stents in coronary artery bypass grafts. EuroIntervention. 2008;4:311-317.
45. Lozano I, Garcia-Camarero T, Carrillo P, et al. [Comparison of drug-eluting and bare metal stents in saphenous vein grafts. Immediate and long-term results]. Rev Esp Cardiol. 2009;62:39-47.
46. Brodie BR, Wilson H, Stuckey T, et al. Outcomes with drug-eluting versus bare-metal stents in saphenous vein graft intervention results from the STENT (strategic transcatheter evaluation of new therapies) group. JACC Cardiovasc Interv. 2009;2:1105-1112.
47. Shishehbor MH, Hawi R, Singh IM, et al. Drug-eluting versus bare-metal stents for treating saphenous vein grafts. Am Heart J. 2009;158:637-643.
48. Goswami NJ, Gaffigan M, Berrio G, et al. Long-term outcomes of drug-eluting stents versus bare-metal stents in saphenous vein graft disease: results from the Prairie “Real World” Stent Registry. Catheter Cardiovasc Interv. 2010;75:93-100.
49. Latib A, Ferri L, Ielasi A, et al. Comparison of the long-term safety and efficacy of drug-eluting and bare-metal stent implantation in saphenous vein grafts. Circ Cardiovasc Interv. 2010;3:249-256.
50. Baldwin DE, Abbott JD, Trost JC, et al. Comparison of drug-eluting and bare metal stents for saphenous vein graft lesions (from the National Heart, Lung, and Blood Institute Dynamic Registry). Am J Cardiol. 2010;106:946-951.
51. Nair S, Fath-Ordoubadi F, Clarke B, et al. Late outcomes of drug eluting and bare metal stents in saphenous vein graft percutaneous coronary intervention. EuroIntervention. 2011;6:985-991.
52. Frobert O, Schersten F, James SK, Carlsson J, Lagerqvist B. Long-term safety and efficacy of drug-eluting and bare metal stents in saphenous vein grafts. Am Heart J. 2012;164:87-93.
53. Nauta ST, Van Mieghem NM, Magro M, et al. Seven-year safety and efficacy of the unrestricted use of drug-eluting stents in saphenous vein bypass grafts. Catheter Cardiovasc Interv. 2012;79:912-918.
54. Chakravarty T, Morrissey RP, Wertman B, et al. Comparison of long-term outcomes of drug-eluting stents and bare metal stents for saphenous vein graft stenosis. Catheter Cardiovasc Interv. 2012;79:903-909.
55. Pasceri V, Tarsia G, Niccoli G, et al. Early beneficial effects of drug-eluting stents in vein grafts wane during long term follow-up: a case-control study. Catheter Cardiovasc Interv. 2012;80:1112-1117.
56. Tolerico PH, Cohen DJ, Kleiman NS, et al. In-hospital and 1-year outcomes with drug-eluting versus bare metal stents in saphenous vein graft intervention: a report from the EVENT registry. Catheter Cardiovasc Interv. 2012;80:1127-1136.
57. Badr S, Kitabata H, Dvir D, et al. Optimal revascularization strategies for percutaneous coronary intervention of distal anastomotic lesions after coronary artery bypass surgery. J Interv Cardiol. 2013;26:366-371.
58. Shugman IM, Idris H, Kadappu KK, et al. Evaluation of a policy of selective drug-eluting stent implantation for patients at high risk of restenosis. Heart Lung Circ. 2013;22:523-532.
59. Ybarra LF, Ribeiro HB, Pozetti AH, et al. Long term follow-up of drug eluting versus bare metal stents in the treatment of saphenous vein graft lesions. Catheter Cardiovasc Interv. 2013;82:E856-E863.
60. Aggarwal V, Stanislawski MA, Maddox TM, et al. Safety and effectiveness of drug-eluting versus bare-metal stents in saphenous vein bypass graft percutaneous coronary interventions: insights from the Veterans Affairs CART program. J Am Coll Cardiol. 2014;64:1825-1836.
61. Brennan JM, Sketch MH Jr, Dai D, et al. Safety and clinical effectiveness of drug-eluting stents for saphenous vein graft intervention in older individuals: Results from the medicare-linked National Cardiovascular Data Registry CathPCI Registry (2005-2009). Catheter Cardiovasc Interv. 2016;87:43-49. Epub 2015 Jul 8.
62. van Beusekom HM, van der Giessen WJ, van Suylen R, Bos E, Bosman FT, Serruys PW. Histology after stenting of human saphenous vein bypass graft: observation from surgically excised grafts 3 to 320 days after stent implantation. J Am Coll Cardiol. 1993;21:45-54.
63. Camenzind E, Steg PG, Wijns W. Stent thrombosis late after implantation of first-generation drug-eluting stents: a cause for concern. Circulation. 2007;115:1440-1455; discussion 1455.
64. Pokala NR, Menon RV, Patel SM, et al. Long-term outcomes with first- vs. second-generation drug-eluting stents in saphenous vein graft lesions. Catheter Cardiovasc Interv. 2016;87:34-40. Epub 2015 May 29.
From the 1University at Buffalo, Department of Medicine, Buffalo, New York; 2McMaster University, Department of Medicine (Division of Cardiology), Hamilton, Ontario; 3University of Dublin, Trinity College, Dublin, Ireland; and 4Peter Munk Cardiac Centre and Heart and Stroke Richard Lewar Centre, University of Toronto, Toronto, Ontario.
Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors report no conflicts of interest regarding the content herein.
Manuscript submitted May 18, 2016, provisional acceptance given June 20, 2016, final version accepted July 26, 2016.
Address for correspondence: Michael E. Farkouh, MD, MSc, FRCPC, FACC, FAHA, 585 University Avenue, 4N474, Toronto, Ontario M5G 2N2. Email: michael.farkouh@uhn.ca