View clinical trials related to Stent Restenosis.
Filter by:If intimal growth is such that the initial lumen is narrowed significantly, distal blood flow is restricted and chronic tissue ischemia results. This occurs in native coronary arteries and during restenosis after coronary angioplasty or failure of some coronary vein grafts. Stent implantation has become the principal revascularization technique for coronary artery disease. But, in-stent restenosis (ISR) by neointimal hyperplasia persists as a significant limitation of this procedure in the era of drug eluting stent (DES). Coronary intervention might induce an inflammatory response by arterial wall damage, release of inflammatory and chemoattractant factors resulting in leukocyte and platelet activation. Then, Migration and proliferation of neointimal smooth muscle cells together with the deposition of extracellular matrix might lead to the development of ISR. It is known that matrix metalloproteinases (MMPs) play a key role in the pathogenesis of restenosis by controlling extracellular matrix degradation and the release of matrix-degrading MMPs, including MMP -2 and MMP-9, which facilitate intimal remodeling after angioplasty. Previous studies showed that increased levels of MMPs in coronary arteries undergoing percutaneous intervention may be associated with vascular remodeling and restenosis by promoting migration of vascular smooth muscle cells. Recently, Gregory et al. demonstrated that elevated serum activities of MMP-2 and -9 are associated with dramatically increased restenosis rates after PCI with implantation of DES. In patients with DESs, determination of MMP levels might be useful for identification of patients who are at high risk for ISR. However, not much is known about the relationship between MMPs and neointimal hyperplasia in patients with DES. In this study, the serum activity of MMP-2 and 9 were investigated in patients who had undergone follow-up coronary angiography with intravascular ultrasound (IVUS), which performed at 9 months post-DES implantation. Our aim was to evaluate if individual or combined levels of MMPs were associated with increased neointimal hyperplasia volume, that is, to evaluate the relationship, correlation between the levels of MMPs and neointimal hyperplasia volume.
The study will evaluate patients with, at least, one previous procedure of coronary revascularization (surgical, percutaneous or both), that are referred for a new, clinically indicated, diagnostic coronary angiography, to describe their clinical characteristics, management, and prognosis, and will propose a prognosis-oriented classification.
The objective of the BIOFLEX-COF trial is to investigate differences in formation of intimal hyperplasia at one and two years after implantation of nitinol-stents with high vs. low COF in de-novo femoropopliteal occlusive lesions in patients with symptomatic peripheral arterial disease. The BIOFLEX-COF trial is a prospective, randomized controlled trial. 80 subjects will be enrolled and randomly assigned to either a high COF group (LifeStent Vascular Stent) or low COF group (Pulsar).