Friday, August 29, 2008


This year saw the FDA approval of two Drug Eluting stents, namely the Endeavor stent by Metronic International, and the XienceV stent by Abbott Vascular. Many of us believe that these two stents form the backbone of the second generation DES. They are both basically thin struts, cobalt chromium stents covered with a -limus drug ( zotarolimus-Endeavor, everolimus-XienceV ). The XienceV stent also has a sister stent called Promus ( promus and XienceV are both identical stents, one marketed by Abbott, and the other as part of the 2006 Boston buy-out, marketed by Boston ). Within months after their approval, both XienceV and Endeavor, have overtaken Taxus and Cypher ( first generation DES ) in terms of market share. JP Morgan did a market survey of 41 high volume centers and form that most of the centers are using second generation DES, with XienceV and Promus doing slightly better than Endeavor. In fact, one expert interventionist is quoted as saying that " In our lab, we're seeing a complete disappearance of the Taxus and Cypher.
Undoubtedly, the second generation DES are more deliverable and the short and medium term results are comparable, if not better than the first generation Taxus and Cypher. However, there is a question mark over the longterm results, especially in terms of late stent thrombosis and restenosis. This did not seem to deter the US interventionist ( so much for evidence base medicine ).
Be it as it may, the second generation DES are good. I have implanted quite a few of them already and they are obviously easier to deliver then the old-fashion Cypher and Taxus. In fact, because they are easy to deliver, interventionist are using them in some lesions which were not quite suited for DES, resulting in some cases of stent dislodgement ( reported cases overseas ) and some case of stent balloon not deflating adequately, with the stent balloon getting stuck. This is what I fear. When angioplasty devices are made so slick and easy to use, everybody will try and put it in all kinds of lesions resulting in all kinds of complications, because of complacency and poor case selection.
But, the bottom line is that Taxus and Cypher have seen better days and in their sunset years. XienceV ( Promus ) and Endeavor and the market leaders ( if JP Morgan survey is to be believed ), but not to worry, there are many new DES in the queue, awaiting approval, to get a piece of this large Interventional devices pie.

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