Ann Thorac Surg 2010;89:1896-1900. doi:10.1016/j.athoracsur.2010.02.080
© 2010 The Society of Thoracic Surgeons
Original Articles: Adult Cardiac
Coronary Artery Bypass Surgery Is Superior to Percutaneous Coronary Intervention With Drug-Eluting Stents for Patients With Chronic Renal Failure on Hemodialysis
Gengo Sunagawa, MD*,
Tatsuhiko Komiya, MD,
Nobushige Tamura, MD, PhD,
Genichi Sakaguchi, MD, PhD,
Taira Kobayashi, MD,
Takashi Murashita, MD
Department of Cardiovascular Surgery, Kurashiki Central Hospital, Kurashiki City, Okayama, Japan
Accepted for publication February 26, 2010.
* Address correspondence to Dr Sunagawa, Department of Cardiovascular Surgery, Kurashiki Central Hospital, 1-1-1 Miwa, Kurashiki City, Okayama, 710-8602 Japan (Email: gengo.sunagawa{at}hotmail.co.jp).
Presented at the Forty-fifth Annual Meeting of The Society of Thoracic Surgeons, San Francisco, CA, Jan 26–28, 2009.
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Abstract
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Background: Improvements in the results of percutaneous coronary intervention (PCI) with drug-eluting stents (DES) have been extending their use in patients with all forms of coronary artery disease. The purpose of this study was to compare the midterm clinical results of coronary artery bypass surgery (CABG) and PCI with DES in patients with chronic renal failure on hemodialysis.
Methods: From January 2002 to December 2006, 29 patients underwent CABG, and 75 patients underwent PCI with DES. For CABG, 24 patients had off-pump surgery. The mean follow-up was 32.0 ± 22.0 months for CABG and 23.5 ± 14.8 months for PCI. Survival, cardiac death, major adverse cardiac events (cardiac death, myocardial infarction, revascularization), and target lesion revascularization were analyzed using the Kaplan-Meier method.
Results: Preoperative characteristics and risk factors were compatible between the groups except for the European System for Cardiac Operative Risk Evaluation (7.3 ± 2.7 for CABG and 5.0 ± 2.4 for PCI, p < 0.0001) and the presence of a left main trunk lesion (53.3% for CABG and 18.7% for PCI). Thirty-day mortality was 3.3% for CABG and 4.0% for PCI. The 2-year survival rate was 84.0% for CABG and 67.6% for PCI (p = 0.0271). The cardiac death-free curve at 2 years was 100% for CABG and 84.1% for PCI (p = 0.0122). The major adverse cardiac events-free rate at 2 years was 75.8% for CABG and 31.5% for PCI (p < 0.0001). During the follow-up period, there were 6 late deaths in the CABG group and 27 late deaths (including 6 sudden deaths) in the PCI group.
Conclusions: Coronary artery bypass grafting was superior to PCI with DES in patients with chronic renal failure on hemodialysis in terms of long-term outcomes for cardiac death, major adverse cardiac events, and target lesion revascularization. The DES carried a higher risk for sudden death, which might be associated with stent thrombosis.
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Introduction
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Coronary artery bypass surgery (CABG) is the established surgical treatment for prolongation of life in patients with coronary artery disease [1]. Chronic renal failure patients form a high-risk group for cardiac surgery, with increased morbidity and mortality [2–5]. There were more than 270,000 Japanese patients on dialysis in 2007. Among patients on dialysis, peritoneal dialysis accounts for 3% and hemodialysis accounts for 97%. About half of the patients on dialysis develop renal failure from diabetic nephropathy. In dialysis patients, arteriosclerotic change is progressive, and coronary arteries often develop severe calcification, along with many branch lesions. The use of the drug-eluting stent (DES) has tended to increase since it was first introduced in Japan, but few studies have compared DES and CABG in hemodialysis patients. We compared DES and CABG to determine which would be superior as revascularization for coronary lesions in hemodialysis patients.
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Patients and Methods
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The Institutional Review Board of Kurashiki Central Hospital approved this study, and waived the individual consent because this study was retrospective. A total of 104 consecutive patients with hemodialysis were treated in our institution between January 2002 and June 2006. Twenty-nine patients were treated by CABG (CABG group) and 75 patients by percutaneous coronary intervention (PCI) with DES (DES group). The study cohort excluded patients who had suffered from acute myocardial infarction with shock and those who underwent concomitant valvular or aortic surgery. The decision to perform PCI or CABG was made primarily by the patients or their physicians.
Percutaneous Revascularization
All patients in the DES group had a sirolimus-eluting stent (Cypher; Cordis, Miami Lakes, FL), a paclitaxel-eluting stent (TAXUS; Boston Scientific Corp, Natick, MA), or a biolimus-eluting stent (Bio Matrix; Biosensors Interventional Technologies Pte Ltd; Singapore) implanted. Both aspirin and ticlopidine were administered throughout the study period in all patients if they experienced no side effects from antiplatelet medications. Angiographic follow-up was scheduled at 3, 8, and 20 months after PCI in the DES group.
Surgical Revascularization
Coronary artery bypass grafting was performed through a median sternotomy in all cases. Off-pump technique was used in all possible cases. Postoperative antiplatelet medication involved only aspirin in patients on warfarin, or both aspirin and ticlopidine were given for 3 months, after which ticlopidine was discontinued.
Endpoints and Statistical Analyses
The primary clinical endpoint was freedom from major adverse cardiac events and mortality. Major adverse cardiac events were defined as death, myocardial infarction, hospitalization because of congestive heart failure, and target lesion revascularization (TLR). The TLR was defined as any revascularization performed on the treated segment.
Comparisons of categoric variables were performed using the 
2 test or Fisher exact test, and continuous variables were analyzed using the Student's t test. Survival and event-free survival were analyzed using the Kaplan-Meier method; the log-rank test was used for comparisons between groups. All analyses were conducted using SAS software, version 5.0 (SAS Institute Inc, Cary, NC).
Follow-Up
Follow-up was obtained by means of direct telephone questionnaire or at the outpatient clinic. The mean follow-up periods were 32 months for the CABG group and 24 months for the DES group.
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Results
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The patients' baseline clinical characteristics are summarized in Table 1. There were important differences between the two groups. Emergent cases, left main trunk disease, and 3-vessel disease were more prevalent in the CABG group. The mean predicted mortality based on the European System for Cardiac Operative Risk Evaluation was significantly higher in the CABG group (7.3 ± 2.7) than in the DES group (5.0 ± 2.4, p < 0.0001).
In the CABG group, the off-pump technique was used in 83%, the on-pump beating technique was used in 10%, and the on-pump arrested heart technique was used in 7%. A left or right internal mammary artery graft was used for revascularization of the left anterior descending artery in all cases. We did not use the radial arteries because they were important access points for hemodialysis. In the DES group, the lesion was located in the right coronary artery (58%), the left anterior descending artery (39%), the left circumflex artery (28%), and the left main trunk (11%).
At 30-day follow-up, the mortality rate was 3.4% in the CABG group and 4% in the DES group. The characteristics of the patients who died within 30 days are shown in Table 2. In the CABG group, there was 1 death, in a patient who underwent emergency surgery for unstable angina pectoris. The cause of death was iatrogenic. The patient developed fatal retroperitoneal bleeding because the temporary hemodialysis blood access penetrated the iliac vein. In the DES group, there were 3 deaths. Two patients died of acute myocardial infarction. They died suddenly after PCI for the right coronary artery. One patient with a left main trunk lesion was treated with PCI, and he developed shock during PCI requiring mechanical support with intraaortic balloon pumping. Unfortunately, he died because of retroperitoneal bleeding.
The two-year mortality, cardiac mortality, TLR, and major adverse cardiac events rates were 16.0%, 0%, 8.9%, and 24.2%, respectively, in the CABG group and 32.4%, 15.9%, 48.1%, and 68.5%, respectively, in the DES group (Figs 1–4).
The mortality rate (all-cause death) and the cardiac mortality rate were significantly higher in the DES group (p = 0.0271, p = 0.0122, respectively). The CABG group had 6 late deaths, including 1 cardiac death. The DES group had 28 late deaths, including 13 cardiac deaths. The causes of death were congestive heart failure in 2 cases and 6 sudden deaths. The characteristics of the late death patients are shown in Table 3. The 6 sudden death patients had no angina pectoris before death.
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Fig 1. Freedom from all-cause death. (CABG = coronary artery bypass surgery; DES = drug-eluting stent.)
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Fig 3. Freedom from target lesion revascularization. (CABG = coronary artery bypass surgery; DES = drug-eluting stent.)
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Fig 4. Freedom from MACE. (CABG = coronary artery bypass surgery; DES = drug-eluting stent; MACE = major adverse cardiac events.)
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In the DES group, there were 30 TLR cases, including 9 patients who were revascularized with CABG. Two of them died, 21 months and 16 months, respectively, after CABG. The other 7 patients are alive, having so far survived a mean of 11.4 months after CABG.
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Comment
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Even in previously reported papers, the mortality and complication rates of open heart surgery for hemodialysis patients were high [6, 7]. The number of dialysis patients increases each year, and their coronary lesions are complicated, with calcified lesions and many branch lesions. It remains controversial whether coronary artery disease in such patients needs aggressive treatment with coronary bypass surgery or less invasive treatment with DES. With respect to hospital mortality, there was no significant difference between CABG (3.4%) and DES (4%). The 2-year survival rate was 84% for CABG and 67.6% for DES, which was not significantly different. There were 6 sudden deaths (8%) and 5 acute myocardial infarctions (6.7%) in the DES group, suggesting that asymptomatic patients may die suddenly. Unfortunately, the causes of the sudden deaths were unknown because autopsies were not performed. Thus, the possibility of in-stent thrombosis cannot be ruled out. Iakovou and colleagues [8] were the first to report that renal failure was an independent predictor of stent thrombosis after implantation of drug-eluting stents. One could expect that CABG would be superior to DES with respect to TLR, and this has been previously reported in patients with normal renal function [9]. As for those who required TLR, there was a total of 30 DES-treated patients; 9 underwent subsequent CABG, and 21 had further PCI. There was no difference between the groups in the survival rate (p = 0.6425). It is important to note that the results of CABG in the present study were not only better than those achieved with DES, but they were also much better than previously reported results in dialysis patients treated with CABG. In the past, the in-hospital death rate of dialysis patients after CABG was reported to range from 6 to 14.8%, while our rate was 3.4%, which is a very good result [6, 7, 10–12]. As for the midterm survival rate, it has been said to be 71 to 72.3% for 1-year survival and 56.4 to 70% for 2-year survival, but our 2-year survival rate was 84% [7, 10, 11, 13]. Use of the left internal mammary artery graft in all cases may be the reason for the good results. Also, the high percentage of off-pump coronary bypass procedures (82.7%) may have affected the result because a long ischemic interval and a long extracorporeal circulation time have been associated with a high mortality rate [10].
Limitations
There are several limitations to the present study. First, this study was not a prospective, randomized study. In addition, the follow-up period was only approximately 2 to 3 years. Further evaluation of a large number of patients with long-term follow-up will be necessary. Second, patient selection bias was present in this study. However, as our hospital is an institution that has results that are outstanding in Japan, it seemed that there would be value in examining the results of such a single institution, and, furthermore, this study reflected real world results in Japan. A large, randomized trial will be necessary to confirm the present results.
Conclusions
In conclusion, CABG was superior to PCI with DES in patients with chronic renal failure on hemodialysis in terms of all-cause death, cardiac death, TLR, and major adverse cardiac events. However, we do not know whether CABG is appropriate treatment when patients with DES are treated again. Drug-eluting stents carried a higher risk for sudden death, which might be associated with stent thrombosis. However, because this was not a randomized trial, much larger, randomized trials are needed in the near future.
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Discussion
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DR JOSEPH COSELLI (Houston, TX): Dr. Sunagawa, thank you for a very clear and excellent presentation. The data are not only provocative but also powerful.
I applaud your effort to cluster left main and triple-vessel disease. Because of the number of patients in your study, did you consider using a propensity score analysis to look at the data with matched pairs? Although it's possible that you may not have had enough events for early mortality to be significant, it probably would have been interesting to analyze the follow-up data. Did you take a look at the data from that perspective?
DR SUNAGAWA: I want to try propensity score, but the number is too small so we couldn't do that.
DR JOSEPH BAVARIA (Philadelphia, PA): The SYNTAX [Taxus and Cardiac Surgery] study was just completed and reported. And when you analyzed the stroke risk, as it turned out, there was a big difference between the medical treatment with the Plavix versus no Plavix in the bypass group versus the CBI group. So was there any difference in the way the patients were treated with aspirin and Plavix or no Plavix?
DR SUNAGAWA: In our institution, PSI group take aspirin and Plavix or ticlopidine. But CABG [coronary artery bypass grafting] group take aspirin and only three months after operation they got ticlopidine.
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References
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- Eagle KA, Guyton RA, Davidoff R, et al. ACC/AHA guidelines for coronary artery bypass graft surgery: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines J Am Coll Cardiol 1999;5:1262-1346.
- Liu JY, Birkmeyer NJ, Sanders JH, et al. Risks of morbidity and mortality in dialysis patients undergoing coronary artery bypass surgery Circulation 2000;102:2973-2977.[Abstract/Free Full Text]
- Shroyer AL, Grover FL, Edwards FH. 1995 Coronary artery bypass risk model: the Society of Thoracic Surgeons Adult Cardiac National Database Ann Thorac Surg 1998;65:879-884.[Abstract/Free Full Text]
- Durmaz I, Büket S, Atay Y, et al. Cardiac surgery with cardiopulmonary bypass in patients with chronic renal failure J Thorac Cardiovasc Surg 1999;118:306-315.[Abstract/Free Full Text]
- Cooper WA, O'Brien SM, Thourani VH, et al. Impact of renal dysfunction on outcomes of coronary artery bypass surgery: results from The Society of Thoracic Surgeons National Adult Cardiac Database Circulation 2006;113:1063-1070.[Abstract/Free Full Text]
- Horst M, Mehlhorn U, Hoerstrup SP, Suedkamp M, de Vivie ER. Cardiac surgery in patients with end-stage renal disease: 10-year experience Ann Thorac Surg 2000;69:96-101.[Abstract/Free Full Text]
- Rahmanian PB, Adams DH, Castillo JG, Vassalotti J, Filsoufi F. Early and late outcome of cardiac surgery in dialysis-dependent patients: Single-center experience with 245 consecutive patients J Thorac Cardiovasc Surg 2008;135:915-922.[Abstract/Free Full Text]
- Iakovou I, Schmidt T, Bonizzoni E, et al. Incidence, predictors, and outcome of thrombosis after successful implantation of drug-eluting stents JAMA 2005;293:2126-2130.[Abstract/Free Full Text]
- Daemen 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;118:1146-1154.[Abstract/Free Full Text]
- Labrousse L, de Vincentiis C, Madonna F, Deville C, Roques X, Baudet E. Early and long term results of coronary artery bypass grafts in patients with dialysis dependent renal failure Eur J Cardiothorac Surg 1999;15:691-696.[Abstract/Free Full Text]
- Herzog CA, Ma JA, Collins AJ. Comparative survival of dialysis patients in the United States after coronary angioplasty, coronary artery stenting, and coronary artery bypass surgery and impact of diabetes Circulation 2002;106:2207-2211.[Abstract/Free Full Text]
- Kan C-D, Yang Y-J. Coronary artery bypass grafting in patients with dialysis-dependent renal failure Tex Heart Inst J 2004;31:224-230.[Medline]
- Hemmelgarn BR, Southern D, Culleton BF, et al. Survival after coronary revascularization among patients with kidney disease Circulation 2004;110:1890-1895.[Abstract/Free Full Text]
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Abstract
Introduction
