<P> Two major randomized controlled trials comparing CABG and DES are either completed or ongoing, and have published results - Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery (SYNTAX) and Future Revascularization Evaluation in Patients With Diabetes Mellitus--Optimal Management of Multivessel Disease (FREEDOM). The five - year follow - up results of SYNTAX showed, depending on the complexity of coronary vessel disease, PCI was either equally effective or inferior to CABG . Similarly, results from the FREEDOM trial published after five years showed CABG to be superior to PCI in reducing rates of death and myocardial infarction . Both trials found either increased or insignificantly different rates of stroke with CABG as compared to PCI . The registries of the nonrandomized patients screened for these trials may provide as much robust data regarding revascularization outcomes as the randomized analysis . </P> <P> Other studies, including the ARTS II registry, suggest drug - eluting stenting is not inferior to coronary bypass for treatment of multiple - vessel coronary disease . The ARTS II registry compared a cohort of patients treated with multiple - vessel stenting with DES, to the historical CABG cohort in the ARTS I trial (itself a randomized comparison between multiple - vessel bare - metal stenting vs. CABG .) At three - year follow - up, major adverse cardiac events were comparable between the ARTS II DES group and the ARTS I CABG group . Reintervention was lower in the ARTS I CABG group . In all comparison studies of stenting vs. bypass surgery, only a small minority of patients with multiple - vessel coronary disease have been eligible for inclusion in the studies, and for most patients, clinical judgement by experienced operators suggest one or the other approach is preferred . </P> <P> Like all invasive medical procedures, implanting stents in the coronary arteries carries risk . For the newer drug - eluting stents, very - long - term results are not yet available; however, five years after implantation, sirolimus - eluting stents remained superior to bare - metal stents . </P> <P> Risks associated with cardiac catheterization procedures include bleeding, allergic reaction to the X-ray contrast agents used to visualize the coronary arteries, and myocardial infarction . With PCI, the requirement for emergency CABG has markedly decreased since the days of balloon angioplasty, such that in some communities, coronary stenting is permitted in hospitals without on - site cardiac surgery facilities, though this remains highly controversial in the United States, not the least because of the rare but largely unpredictable risk of coronary artery perforation . Rarely, a type of allergic reaction to the drug may occur; episodes of fatality have been reported . </P>

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