Stents are effectively tubes that are inserted into the coronary arteries to hold them open after they have become blocked. A blocked coronary artery or ‘thrombosis’ is the chief cause of heart attack or myocardial Infarction (MI). The theory is perfect, but in practice is was found that the stents themselves then became a cause of further blockage by blood deposits (atherosclerosis) and so the next step was to produce stents that were impregnated with drugs that had atherosclerosis busting properties. Again, the theory sounds good, but it took some time before the best stent and drug eluent combinations were found.
The latest findings have been published by one of the major manufacturers themselves, Medtronic. They report that the new clinical trial involving their drug eluting stent (DES) demonstrates the long-term benefits offered by drug-eluting stent technology to coronary artery disease patients. The trial is the largest prospective randomised drug-eluting stent trial ever presented and was carried out to assess the risk posed by stent thrombosis. The trial involved more than 8,700 patients across three years of follow-up, and found that occurrences of stent thrombosis were extremely uncommon, thus demonstrating the long-term safety of the 
devices.
Results from this trial also show that stent thrombosis rates have fallen considerably in recent years, which could be due in part to better procedural / surgical techniques and patient selection. Dr Wijns, an interventional cardiologist and co-director of the Cardiovascular Center in Aalst, Belgium, said: "Based on its excellent clinical outcomes and low rates of stent thrombosis through three years of follow-up, this trial confirms the long-term safety of percutaneous coronary intervention with these drug-eluting stents."
