Wednesday, November 09, 2011


I have been searching the internet for the last 3 days to see what is happening at TCT 2011, San Francisco. The truth maybe that nothing is happening. Is that true, or is there a cyber-blackout by the organisers. ( I doubt it ). TCT ends tomorrow, I think, and to date, looks like the most interesting news posted out was a paper by Dr Paul Williams of Manchester Heart Center on 10 cases of longitudinal stent compression, in 9,411 stents implanted by them. An incidence of 0.11%. What he means is that, when stents ( and in this era, mainly DES ) were implanted, some of them can be pushed inwards, and so the distal stent segment telescope into the mid portion of the stent.
If you remember, I reported on 3 cases published by the Irish, earlier, and they were all ( in my opinion ), due to procedural factors like guiding catheter abating on the stents. In Dr Williams presentation, he cited ( unfortunately ), the stent make, trying to make an issue that these cases of longitudinal stent compression were due to faulty stent design. Of his 10 cases, 7 were Promus Element, 1 each of Taxus, Endeavour and Biomatrix. I have not seen the details of each of the 10 cases, so I do not know if bad technique was to blame. Dr Williams message seemed to be that the Promus Element is poorly designed to with stand longitudinal stent compression. There is some truth in that. But, this slightly poor stent design ( from the longitudinal stent weakness point of view ), is off set by its greater deliver-ability, and also very good radial strength. It must also be remembered that the Promus element stent is more radio-opague and so any compression may be easier to see. What I fear most in these kind of paper ( if you think that there is an ulterior motive ), is that stent wars ( companies marketing their stents, have taken to attacking stent designs of competitors ), are getting more heated and more personal. I would have liked companies to tell us how good their stent is, and not how bad their competitor stents are.
When I was at ICF 2011, Kuching in early October, I was spoken to at some length about this issue, with bench testing data, etc.. I told them that in my opinion, the 3 cases from Ireland, were due to technical factors and no stent can withstand the guiding catheter directly abating the stent. That was the prodrome to this TCT presentation.
Anyway, like most of the commentaries after the Williams' paper, I feel that stenting techniques have to do with some of these longitudinal stent weakness issues, and operators must be more vigilant when implanting stents, and not do it carelessly, as some stents are so deliverable now. It is worth noting that the strongest stent, from the longitudinal stent strength point of view, is the now withdrawn Cypher stent. And we all know how much tougher it was to get that down. The tougher it is to get that stent down, the more care I take in choosing the stent, and in delivering the stent, and so there is less stent longitudinal compression issues.
We will keep watching this scene, but I must say that there is actually nothing much to watch for. All we need, I think, is for operators to be more careful, especially for those who choose to use the Promus Element stent, when they are implanting that stent. The rest of us, who do not use that stent, should also exercise equal care and caution, when implanting the Endeavour or Xience V because the message must be that longitudinal stent compression is avoidable, if we are meticulous in our technique, and not be rushing for tee off or a dinner meeting in 30 mins.
The other message must be, what is happening at TCT 2011 San Francisco. Is this major interventional meeting talking about gossip issues? Has the worldwide financial downturn cause it to be less glamorous?
Well, I do not know. I am just thinking aloud.

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