A network meta-analysis of 38 randomized controlled trials encompassing more than 18,000 patients found that the mortality risks associated with drug-eluting stents and bare-metal stents are similarly low. This analysis, the largest of its kind to date comparing drug-eluting stents (the CYPHER® Sirolimus-eluting Coronary Stent and the Taxus Stent) to bare-metal stents, appears this week in the medical journal The Lancet.
The analysis also found a substantial reduction in the risk of myocardial infarction (heart attack) and reintervention with the CYPHER® Stent when compared to bare-metal stents and the Taxus Stent, and no significant differences in the rates of stent thrombosis (blood clots) between the CYPHER® Stent and bare-metal stents.
The data from this analysis also identifieda significant decrease in the risk of blood clots occurring more than 30 days after stent implantation with the CYPHER® Stent compared to the Taxus Stent.
“This large set of data indicates that the mortality associated with drug-eluting stents and bare-metal stents is comparable. Recent concerns about increases in mortality associated with drug-eluting stents are not supported by thisanalysis assessing long-term outcomes,” stated Dr. Christoph Stettler, M.D., from the University of Bern, Switzerland, one of the authors of the study. Dr. Stettler is with the Department of Endocrinology, Diabetes and Clinical Nutrition there.
In addition, the corresponding author, Dr. Peter Juni, M.D., stated that, “These results have also led us to conclude that the CYPHER® Stent is clinically superior to bare-metal stents and the Taxus Stent when the safety and effectiveness outcomes in this analysis are taken into account.” Dr. Juni is Head of Division, Clinical Epidemiology and Biostatistics, University of Bern in Switzerland.
Funded by the Swiss National Science Foundation, this network meta-analysis was designed to compare the safety and effectiveness of bare-metal stents, the CYPHER® Stent and the Taxus Stent in a large patient population to increase the ability to detect and understand low frequency events, such as death and stent thrombosis. It included data up to four years of follow-up. The safety outcomes comprised mortality (death), myocardial infarction and Academic Research Consortium (ARC) definite stent thrombosis. The effectiveness outcome was target lesion revascularization (or the need for a repeat intervention).
The mortality rates were similar for all three stents: hazard ratios (HR) were 1.00 (95 percent credibility interval 0.82 to 1.25) for the CYPHER® Stent versus bare-metal stents, 1.03 (CI 0.84 to 1.22) for the Taxus Stent versus bare-metal stents and 0.96 (CI 0.83 to 1.24) for the CYPHER® Stent vs. the Taxus Stent.
The CYPHER® Stent was associated with the lowest risk of myocardial infarction. The corresponding hazard ratios were 0.81 versus bare-metal stents (CI 0.66 to 0.97, p=0.030) and 0.83 versus the Taxus Stent (CI 0.71-1.00, p=0.045).
The ARC definite stent thrombosis rates between the CYPHER® Stent and bare metal stents were not significantly different over the entire follow-up. However, the risk of late stent thrombosis (occurring more than 30 days after the procedure) was more than twice as likely with the Taxus Stent compared to bare-metal stents (HR 2.11, CI 1.19-4.23, p=0.017). In addition, the study found that a late stent thrombosis event was 46 percent less likely to occur in a patient implanted with the CYPHER® Stent than in a patient who received the Taxus Stent (HR 0.54, CI 0.26-0.98, p=0.041).
While both drug-eluting stents were associated with significantly lower risks of target lesion revascularization compared to bare-metal stents, the CYPHER® Stent reduced the risk substantially further compared to the Taxus Stent. The CYPHER® Stent reduced the risk by 70 percent (HR 0.30, CI 0.24 to 0.37, p=0.0001) and the Taxus Stent by 58 percent (HR 0.42, CI 0.33 to 0.53, p=0.0001) compared to bare-metal stents. When the target lesion revascularization rate for the CYPHER® Stent was compared directly to the rate for the Taxus Stent, a patient implanted with the CYPHER® Stent was found to be 30 percent less likely to need another procedure than a patient treated with the Taxus Stent (HR 0.70, CI 0.56 to 0.84, p=0.0021).This difference is consistent with other meta-analyses of randomized controlled trials directly comparing the two stents.
“This network meta-analysis constitutes the largest and most robust set of data published to date in an eminent international peer-reviewed journal assessing the long-term safety and efficacy outcomes of drug-eluting stents,” said David E. Kandzari, M.D., F.A.C.C., F.S.C.A.I., Chief Medical Officer, Cordis Corporation. “It significantly enriches the large body of evidence that interventional cardiologists have at their disposal to make the right choice for their patients. These data clearly demonstrate the benefits of drug-eluting stents versus bare metal stents and further provide clarity as to the differences between the CYPHER® Stent and the Taxus Stent.”