Monday, August 04, 2008


Drug Eluting Stents ( DES ) have become a very important device in the management of coronary artery disease. Many of us believe that their longterm results are as good as CABG, and with her minimal invasiveness, ha become very popular among cardiologist and patients. The ESC congress in Sept 2006, Barcelona, will always stand out as the event which warned us ( as we now know, wrongly ) that DES does have potential risk. An 0.4-0.5% risk of stent thrombosis, which will invariably result in a heart attack, from which about 30% of the patients may die, some suddenly. Well from Sept '06, till March '08, interventionist were defensively trying to defend the safety of DES. Well, analysis and re-analysis of past data, and the publication of more new data, seem to show that the risk of stent thrombosis was not anymore than bare metal stents. Stent thrombosis seem to be a risk associated with all stents, bare metal and DES. If a patient wish to have a coronary stent, he / she must be warned that there is a 0.4-0.5% risk of stent thrombosis, some coming almost 2-3 years after the stent implantation. But the good news from Sept '06 is that, having all us re-evaluate our data, also cause many of us to re-evaluate our procedural technique and post-implantation drug regiments. In other words, we were also caused to pay greater attention to how the procedure should be done and how to care for the patient thereafter, and not to just down the stent any old how. We now know that the use of plavix for one year at least is mandatory. That those who cannot take plavix in the first year, for whatever reasons, should not get a DES.
Well, this post is also partly prompted by the recent enrollment of patients for the PROTECT trial ( notice that interventionist chose very nice acronyms for their trials ). This is a study, initiated by Metronic International, to test the safety of their Endeavor DES against the benchmark Cypher DES of Johnson n Johnson. It is a randomised controlled prospective trial, almost like a registry, to follow patients on Endeavor and Cypher, and compare their stent thrombosis rates and also efficacy, at three years. They intend to enroll 8,800 patients ( I wonder why 8,800? ). I guess part of the reason for this trial is the condition that FDA has imposed on Metronic when they applied for FDA approval in 2007 ( after the furor of Sept 2006 ). FDA by then had approved Cypher, and Metronic claimed that their Endeavor is as safe as
cypher. Lacking longterm post-market surveillance data then, FDA had asked them to do post-market surveillance. And so the PROTECT trial. Be that as it may, we will have more data, regarding the safety of DES. The cardiac surgeons cannot then say that the interventionist were careless and irresponsible. ( Which was one of the accusations back in Sept 2006 ).
Besides, in this era of " Corporate Responsibility " this is probably the very right think to do. Well done Metronic International.

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