View clinical trials related to Coronary Stenosis.
Filter by:The gold standard to induce coronary hyperemia for measurement of fractional flow reserve (FFR), coronary flow reserve (CFR) and index of microcirculatory resistance (IMR) is adenosine, but it exerts several side effects due to its unspecific action on adenosine receptors. The specific A2a-receptor agonist, regadenoson, has been shown to dilate coronary arteries and enables FFR measurements. The aim of the study was to evaluate whether simultaneous measurement of FFR, CFR and IMR is feasible, safe and effective within regadenoson-induced hyperemia.
This is a pilot study designed to assess the relationship between iFR (instantaneous wave-free ratio) pullback and the distribution of coronary atheroma/stenoses as assessed by Quantitative Coronary Angiography (QCA) post angiographically successful PCI (Percutaneous Coronary Intervention).
Coronary fraction flow reserve (FFR), the ratio of the mean coronary pressure distal to a coronary stenosis to the mean aortic pressure during maximal coronary blood flow (hyperemia), defines the hemodynamic significance of coronary artery narrowing. Noninvasive assessment of FFR via a combination of computational fluid dynamics (CFD) and coronary CT angiography CCTA (the so-called FFRCT) has potential. Coronary computed tomographic angiography is a noninvasive test for diagnosis of anatomic coronary stenosis (i.e., narrowing of a blood vessel). A new analytical model of FFR from the general Bernoulli equation (conservation of energy) (FFRB) is simple and has potential. A collaborator group has recently developed a new analytical model to quantify pressure drop, and hence FFR, based on lesion dimensions (i.e., the cross-section area along the lesion and the length of lesion) and coronary flow, with no empirical parameters. The investigators hypothesize that this new model will allow quantification of FFR (FFRB) in a cohort of human patients with intermediate coronary stenosis. The study will compare FFRB with invasive FFR measurements from invasive coronary angiography (ICAG).
The aim of the study is to compare different devices available to measure fractional flow reserve (FFR) in coronary arteries.
Revascularization of borderline coronary stenoses (40-70%) is usually driven by fractional flow reserve (FFR) which expresses the physiological significance of a lesion and tells the operator whether PCI may reduce the rate of adverse events as compared to medical therapy. Coronary stenoses with FFR value < 0.80 are indeed associated with a higher rate of adverse event and requires coronary revascularization whereas lesions with FFR > 0.80 show an excellent prognosis which cannot be improved by coronary stenting. Such a predictive value of FFR is theoretically based only on the degree of myocardial ischemia downstream from a given coronary stenosis: however, also plaque composition may play a crucial role in triggering future events especially in patients affected by acute coronary syndrome. Differences in plaque composition between FFR-positive and FFR negative lesions have never been assessed. Intracoronary Near-InfraRed Spectroscopy (NIRS) identifies lipid rich plaques that can potentially cause acute events. The aim of this study is to compare the lipid content expressed by LCBI (Lipid Core Burden Index) between functionally significant (FFR < 0.80) and non-significant (FFR > 0.80) stenoses in patients undergoing coronary angiography because of stable CAD and non-ST elevation acute coronary syndromes. This is an observational, prospective, multicentric study where we plan to collect 150 coronary lesions.
The purpose of this study is to compare clinical outcomes between quantitative coronary angiography -guided and Intravascular ultrasound -guided strategy in patients with significant coronary artery disease undergoing sirolimus-eluting Orsiro/Orsiro mission stent implantation.
One hundred Spanish postmenopausal women accepted to be investigated for cardiovascular risk actors including clinical features, serum biochemical parameters, single nucleotide polymorphisms for estrogen receptor, and imaging parameters, carotid intima-media thickness (91 women) and coronary computed tomography (32 women). Multivariable analysis confirmed that both age and glucose level directly affected IMT. Estrogenic exposure, as measured by the allele associated with lower expression of the ER beta gene, was protective at the sinus and the wall. Findings at the coronary arteries, either moderate or high calcium index (CAC) and/or significant lumen stenosis were sporadic and did not allow for establishing association with any of the variables assessed.
The purpose of this study is to determine the optimal way of predilatation for BVS implantation.
The purpose of this study is to evaluate the efficacy and safety of RESTORE Paclitaxel eluting balloon in the treatment of Chinese patients with coronary heart disease and small vessel lesions in comparison with RESOLUTE Zotarolimus eluting stent.
Regional absolute myocardial blood flow during stress (sMBF) as measured by Positron Emission Tomography (PET) improves post mechanical revascularization provided there is a baseline stress induced perfusion defect. Coronary revascularization performed on regions without a stress induced perfusion defect does not increase the sMBF.