Drug-eluting stents (DES) have also been extensively studied, and are generally superior to bare-metal stents with respect to occurrence of major adverse cardiac events (MACE, generally defined as death, myocardial infarction, or the need for a repeat revascularization procedure).
Stents are indicated to improve the diameter of the coronary artery lumen, when narrowing (generally because of atherosclerosis) causes ischemia (reduced oxygen delivery to the muscle supplied by that artery).
The Pd/Ce Zr Al Ox material exhibited long-term stability and selectivity to propene (during continuous operation for 140 h), which is not normally associated with dehydrogenation catalysts.
From temperature-programmed desorption of NH3 and CO2 it was found that the catalyst possessed both acidic and basic sites.
This prevents fibrosis that, together with clots (thrombi), could otherwise block the stented artery, a process called restenosis.
The stent is usually placed within the peripheral or coronary artery by an interventional cardiologist or interventional radiologist during an angioplasty procedure.
For "on-label" applications, the FDA "believes that coronary drug-eluting stents remain safe and effective when used for the FDA-approved indications.
These devices have significantly reduced the need for a second surgery to treat restenosis for thousands of patients each year." with worse outcomes for the patients in both studies.however, use in these bypass grafts is an example of an "off-label" use of drug-eluting stents.That is, this application has not been sufficiently examined by the Food and Drug Administration for that agency to recommend the use.The registries of the nonrandomized patients screened for these trials may provide as much robust data regarding revascularization outcomes as the randomized analysis.Other studies, including the ARTS II registry, suggest drug-eluting stenting is not inferior to coronary bypass for treatment of multiple-vessel coronary disease.It is proposed that CO2 has the dual role of regenerating selective oxygen species and shifting the equilibrium for alkane dehydrogenation by consuming H2 through the reverse water-gas-shift reaction.