CABG vs Stenting: Which is Better?
Special Report
By Harold L. Karpman, MD, FACC, FACP, Clinical Professor of Medicine, UCLA School of Medicine. Dr. Karpman reports no financial relationship to this field of study.
A meta-analysis comparing percutaneous balloon angioplasty alone vs coronary artery bypass grafting (CABG) demonstrated no significant differences in mortality and nonfatal myocardial infarction (MI) however, a statistically significant benefit in terms of survival in favor of surgery1 was noted. It should be clearly recognized that the results obtained favoring surgery in these 9 early studies is of questionable value since the data was acquired during the pre-stent era and also, more recent studies have revealed mixed findings.2,3
Serruys and associates reported on the 5-year survival and event-free survival in the 1205 patients in the Arterial Revascularization Therapies Study (ARTS) randomized trial.4 The primary clinical end point was freedom from major adverse cardiac and cerebrovascular events (MACCE) at 1-year and the secondary end point was acquiring the same end point data at the 5 years follow-up. Overall, freedom from death, stroke, or MI was not significantly different between the groups however, the incidence of repeat revascularization procedures were significantly higher in the stent group than in the CABG group. The composite event-free survival rate was 58.3% in the stent group and 78.2% in the CABG group.
A second article in the same issue of the Journal of the American College of Cardiology by Rodriguez and associates reported the 5-year follow-up of the Argentine randomized trial of coronary angioplasty with bare-stenting vs CABG in patients with multiple vessel disease (ERACI II).5 The immediate and one-year follow-up result of the ERACI II study had previously demonstrated a prognosis advantage of percutaneous coronary intervention (PCI) bare-metal stents over CABG.3 Clinical follow-up over the 5-year time period was obtained in 92% of the 450 patients who were randomly assigned to undergo either PCI or CABG. At five years follow-up, there were no survival benefits from either revascularization procedure and similar numbers of patients randomized to each procedure were either asymptomatic or were afflicted with only class 1 angina. However, freedom from repeat revascularization procedures and freedom from major adverse cardiovascular events was significant lower in the PCI group when compared to the CABG group.
Commentary
The results of the 2 studies4,5 reviewed above show a highly significant difference in repeat revascularization favoring CABG and a more modest benefit of CABG with regard to angina over time. The ARTS4 study demonstrated a clear trend toward a lower composite event rate (ie, death, MI, or stroke) with CABG but with no such trend was noted in the ERACI II5 study. Compared with CABG patients, patients with multivessel disease treated with PCI had an increased incidence of repeat revascularization procedures at follow-up and, as a result, the ERACI II5 found a higher cost per patient over time when the initial strategy of treatment was PCI. One of the difficulties in analyzing the results of these studies is the possibility that the drug-eluting stents which are currently being utilized may eventually demonstrate significant improvement over bare-metal stents and, therefore, over the long-term, PCI in the modern era may prove to be equal or better than CABG with respect to the end points outlined above.
As technologies and procedures improve, new findings will have to be integrated into practice decisions and clinical research and outcome studies which are in a continual state of flux will eventually define quality. For example, the off-pump coronary bypass technique which was developed in order to minimize the invasiveness of CABG, has already in several large retrospective studies resulted in a reduction in morbidity and and/or mortality when compared to standard CABG and, of course, the use of drug eluding stents has dramatically reduced the need for repeat revascularization in both diabetic and nondiabetic patients. Information similar to that produced by the ERACI II and ARTS studies4,5 is critical but the conclusions drawn from the results of these studies may change dramatically as new technologies come into widespread clinical practice. The final chapter comparing CABG to PCI is therefore yet to be written.
References
1. Hoffman SN, et al. A meta-analysis of randomized controlled trials comparing coronary artery bypass graft with percutaneous transluminal coronary angioplasty: one- to eight-year outcomes. J Am Coll Cardiol. 2003; 41:1293-1304.
2. SoS Investigators. Coronary artery bypass surgery versus percutaneous coronary intervention with stent implantation in patients with multivessel coronary artery disease (the Stent or Surgery trial): a randomised controlled trial. Lancet. 2002;360:965-970.
3. Rodriguez A, et al. Argentine Randomized Study: Coronary Angioplasty with Stenting versus Coronary Bypass Surgery in patients with Multiple-Vessel Disease (ERACI II): 30-day and one-year follow-up results. ERACI II Investigators. J Am Coll Cardiol. 2001;37:51-58; Erratum in: J Am Coll Cardiol. 2001;37:973-974.
4. Serruys PW, et al. Five-year outcomes after coronary stenting versus bypass surgery for the treatment of multivessel disease: the final analysis of the Arterial Revascularization Therapies Study (ARTS) randomized trial. J Am Coll Cardiol. 2005;46:575-581.
5. Rodriguez AE, et al. Five-year follow-up of the Argentine randomized trial of coronary angioplasty with stenting versus coronary bypass surgery in patients with multiple vessel disease (ERACI II). J Am Coll Cardiol. 2005;46:582-588.
A meta-analysis comparing percutaneous balloon angioplasty alone vs coronary artery bypass grafting (CABG) demonstrated no significant differences in mortality and nonfatal myocardial infarction (MI) however, a statistically significant benefit in terms of survival in favor of surgery1 was noted.You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content