March 22nd, 2012
Large Meta-Analysis Finds Very Low Thrombosis Rates for Xience Stent
Larry Husten, PHD
A large new meta-analysis published in the Lancet provides the best evidence yet that the cobalt-chromium everolimus eluting (CoCr-EES) stents (Xience and Promus) have a significantly lower rate of stent thrombosis than bare-metal stents (BMS) and other drug-eluting stents (DES).
Tullio Palmerini and colleagues analyzed data from 49 randomized trials comparing different stents in more than 50,000 patients.
Odds ratios for 1-year definite stent thrombosis for CoCr-EES compared with:
- BMS: OR 0·23, CI 0·13–0·41
- paclitaxel-eluting stents: OR 0·28, CI 0·16–0·48
- permanent polymer-based sirolimus-eluting stents: OR 0·41, CI 0·24–0·70
- phosphorylcholine-based zotarolimu-seluting stents: OR 0·21, CI 0·10–0·44
- Resolute zotarolimus-eluting stents: OR 0·14, CI 0·03–0·47
The superiority of the CoCr-EES over BMS emerged within the first month, suggesting that the findings were not simply a reflection of longer duration of dual antiplatelet therapy. At 2 years, the CoCr-EESs still had a lower rate of definite stent thrombosis than both bare-metal stents (OR 0·35, CI 0·17–0·69) and paclitaxel-eluting stents (OR 0·34, CI 0·19–0·62). Since concerns were first raised a number of years ago about the higher rate of stent thrombosis with drug-eluting stents, the new results, write the authors, represent “a paradigm shift.”
In an accompanying comment, John Ormiston and Mark Webster point out that a meta-analysis should only “be regarded as hypothesis-generating,” but write that “despite these limitations” the findings are “very reassuring.” They conclude: “CoCr-EES should be regarded as the standard against which future design improvements are compared.”