Advances in Catheter Based Physical Treatments
Interventional procedures have been plagued by restenosis due to the formation of endothelial tissue overgrowth at the lesion site. Restenosis is the body's response to the injury of the vessel wall from angioplasty and to the stent as a foreign body. As assessed in clinical trials during the late 1980 and 1990s, using only balloon angioplasty (POBA, plain old balloon angioplasty), up to 50% of patients suffered significant restenosis but that percentage has dropped to the single to lower two digit range with the introduction of drug-eluting stents. Sirolimus, paclitaxel and everolimus are the three drugs used in coatings which are currently FDA approved in the United States. As opposed to bare metal, drug eluting stents are covered with a medicine that is slowly dispersed with the goal of suppressing the restenosis reaction. The key to the success of drug coating has been (a) choosing effective agents, (b) developing ways of adequately binding the drugs to the stainless surface of the stent struts (the coating must stay bound despite marked handling and stent deformation stresses) and (c) developing coating controlled release mechanisms that release the drug slowly over about 30 days. One of the newest innovations in coronary stents is the development of a dissolving stent. Abbott laboratories has used a dissolvable material, polylactic acid, that will completely absorb within 2 years of being implanted.
Read more about this topic: Coronary Catheterization
Famous quotes containing the words advances, based and/or physical:
“The good is, like nature, an immense landscape in which man advances through centuries of exploration.”
—José Ortega Y Gasset (1883–1955)
“The time must come, my friend ... when brutality and the lust for power must perish by its own sword.... For when that day comes, the world must begin to look for a new life, and it is our hope that they may find it here. For here we shall be, with their books, and their music, and a way of life based on one simple rule: Be kind.”
—Robert Riskin (1897–1955)
“I have no purpose to introduce political and social equality between the white and black races. There is a physical difference between the two, which, in my judgement, will probably for ever forbid their living together upon the footing of perfect equality; and inasmuch as it becomes a necessity that there must be a difference, I ... am in favour of the race to which I belong having the superior position.”
—Abraham Lincoln (1809–1865)