View clinical trials related to Myocardial Ischemia.
Filter by:Rationale: In patients with a myocardial infarction, occlusion of a coronary artery induces myocardial ischemia and cell death. If untreated, the area of myocardium exposed to this interruption in blood supply, will largely become necrotic. The only way to limit final infarct size, is timely reperfusion of the occluded artery. Paradoxically, however, reperfusion itself can also damage myocardial tissue and contribute to the final infarct size ("reperfusion injury"). Also during coronary artery bypass grafting (CABG), the myocardium is exposed to ischemia and reperfusion, which will induce cell death. Indeed, postoperatively, the plasma concentration of troponin I, a marker of cardiac necrosis, is increased, and associated with adverse outcome. The anti-hyperglycaemic drug metformin has been shown in preclinical studies to be able to reduce ischemia-reperfusion injury and to limit myocardial infarct size. Moreover, metformin therapy improves cardiovascular prognosis in patients with diabetes mellitus. Paradoxically, in patients with diabetes, current practice is to temporarily stop metformin before major surgery for the presumed risk of lactic acidosis, which is a rare complication of metformin. However, here is no evidence that this practice benefits the patient. The investigators hypothesize that pretreatment with metformin can reduce myocardial injury in patients undergoing elective CABG surgery
Adventitial vasa vasorum (VV) as well as intraplaque microvessels are known to be associated with atherosclerotic plaque vulnerability. Contrast-enhanced ultrasound has been validated as a technique to measure the density of VV. Previous studies have demonstrated a relationship between identification of VV and relationship to vascular events such as stroke and myocardial infarction. No previous study has reported the utilization of contrast-enhanced ultrasound identification of VV in the carotid bed as a means of identifying patients at high risk for acute coronary events. Aims: In this study, the investigators will aim to identify VV and intraplaque microvessels along with carotid intima media thickness (CIMT), a known marker for acute coronary events. The investigators will attempt to measure the correlation of VV with acute coronary events independent of traditional cardiovascular disease (CVD) risk factors and CIMT. Methods: 90 volunteers (30 low risk patients, 30 patients with established coronary artery disease (CAD), and 30 patients with recent acute coronary syndrome (ACS)) will be enrolled. All patients will undergo contrast-enhanced ultrasound imaging of their carotid arteries and measurement of CIMT while obtaining baseline histories and assessment of traditional risk factors for coronary artery disease. VV density and CIMT will be measured in all patients. Statistical differences in VV among the three groups will be assessed and analyses will be made to attempt to identify if VV in the carotid bed is an independent predictor of acute coronary events after controlling for CIMT and traditional risk factors. Study population: The study population will reflect the patient population of UPMC. No individual will be excluded on the basis of race, gender, or ethnicity.
Intensive therapy with rosuvastatin 40 mg and ApoA-I Milano reduces the total atheroma volume (TAV) up to 6.38 or 14.1 mm3 respectively. Our previous bench studies PLASMONICS and NANOM First-in-Man trial documented TAV reduction up to unprecedented 79.4 and 60.3 mm3 respectively with high level of safety and feasibility. The completed randomized two arm (1:1) study (NANOM-PCI) with parallel assignment (n=62) assessed (NCT01436123) the safety and feasibility of the delivery technique for nanoparticles (NP) using micro-injection catheter (with intravascular intramural injection of allogeneous stem cells carrying NP after MSCT-, IVUS- and OCT-guided mapping of the vessel), and plasmonic photothermal therapy of atherosclerosis combined with stenting (Nano group, n=32) versus stenting with Xience V cage (Stenting group, n=30). The primary outcome was TAV at 12 months. The mean reduction of TAV at 12 months in Nano group was -84.1 mm3 (95% CI: SD 28.3; min -52.4 mm3, max -99.1 mm3; p<0.05) versus +12.4 mm3 in case of stenting (p<0.05 between groups). 42/62 patients (68%) in Nano group passed the Glagov threshold of a 40% plaque burden with mean plaque burden (PB) 36.2% (95% CI: SD 9.3%, min 30.9%, max 44.5%). The increase of the minimal lumen diameter was 61.2 and 63.3% at 12 month follow up in groups respectively. The serial assessment of VH-IVUS showed a significant decrease at 12 months in the dense calcium area, fibrous and fibro-fatty tissue with fulminant necrosis due to thermolysis in Nano-group, whereas an increase of fibrous and fibro-fatty components in stenting arm. We have documented 2 vs 3 cases of the definite thrombosis and 3 vs 5 cases of target lesion revascularization in groups respectively. The analysis of the event-free survival of the ongoing clinical follow-up shows the significantly lower risk of cardiovascular death in Nano group if compare with conventional stenting (93.4% vs 86.7%; p<0.05). Plasmonic resonance-mediated therapy using noble-metal NP associated with significant regression of coronary atherosclerosis. Tested delivery approach has acceptable safety and efficacy for atheroregression below a 40% PB. The investigators hypothesize that multistep approach with the use of stent in acute care unit, and then subsequent transcatheter micro-injection with nanoparticles can resolve atherosclerosis, stop and regress atherogenesis, remodulate or even rejuvenate arteries. Stem cells in patch can be good carriers for nanoparticles as well as high-effective metabolic vectors (paracrine-like regulation of alive cells and via bioactive products of cell lysis after detonation of nanoparticles) for the treatment of plaque on site. Gold nanoparticles with silica-iron oxide shells promise high-energy plasmonic photothermic burning or melting effect under the near-infrared laser irradiation onto the lesion. Thus the investigators expect complex two-side effect on the plaque with protected lumen and adventitia. Novel discoveries in atherogenesis, and development of nanobiotechnologies with potentials for the management of atherosclerosis leads us to the quest of new approaches. The investigators still cannot really effectively treat atherosclerosis. The investigators management is more symptomatic, and lipid-pool or inflammation-oriented! The investigators cannot manage non-organic part (mineral deposits, calcified necrotic core, partially collagen and fibrotic tissue) and total plaque volume Surgery and invasive procedures is just focused on blood flow restoration (just manipulate the form of plaque) + concerns of clinical and technical restrictions (incl. alien body - stent) + risk of restenosis or subacute 'fatal' in-stent atherothrombosis + graft survival/ occlusion + surgery-related complications High rate of short- and long-term complications and readmissions. Regression of atherosclerosis in fact is still a dream. The investigators offer an alternative to stenting and may be cardiac artery bypass surgery (CABG). Our approach can really allow to rejuvenate arteries, Plasmonic photothermal therapy (PPTT) can burn plaque, but stem cells and bioengineered structures promise restoration of the vessel wall. Our personal previous data showed that PPTT can 1.6-fold reduce a volume of plaque with most optimal long-term result in subsets with the use of SPCs as a delivery approach. The most optimal delivery systems of NPs into the plaque are the on-artery bioengineered patch and ferro-magnetic approach.
A prospective, multi-center, single-arm study to establish the safety and effectiveness of the XIENCE V® Everolimus Eluting Coronary Stent, XIENCE nano™ Everolimus Eluting Coronary Stent, XIENCE PRIME™ LL Everolimus Eluting Coronary Stent, HT PROGRESS and HT PILOT Coronary Guide Wires, and MINI-TREK Coronary Dilatation Catheter in patients undergoing elective percutaneous revascularization of native chronic total coronary occlusions
This protocol details a novel myocardial perfusion Single Photon Emission Computed Tomography (SPECT) protocol wherein patients receive a low-dose (6 mCi) of Tc-99m sestamibi during exercise or regadenoson pharmacologic stress and undergo a full-time SPECT acquisition processed with Wide Beam Reconstruction (WBR). Immediately thereafter patients receive a high-dose (30-35 mCi) of Tc-99m sestamibi at rest and undergo a half-time rest scan, also processed with WBR. All enrolled research subjects will undergo both the initial stress and subsequent rest scan. The radiation exposure associated with this new stress/rest protocol is equivalent to that of the conventional rest/stress protocol presently in routine clinical uses at SLRHC. Eventually, when and if this novel stress/rest protocol is adopted in routine clinical practice, patients with normal stress scans would receive only 6 mCi of Tc-99m sestamibi (331 mSv in men, 241 mSv in women) and spend only approximately one hour in the Nuclear Medicine Laboratory. All patients presenting to the Nuclear Medicine Laboratory for evaluation of known or suspected coronary artery disease will be candidates for enrollment. Fifty patients undergoing treadmill exercise stress and 50 patients undergoing regadenoson pharmacologic stress will be enrolled. Pregnant and breast-feeding patients will not be eligible.
This purpose of this research project is to test the diagnostic accuracy (i.e., sensitivity, specificity, positive and negative predictive value, and receiver operator curve area under the curve) of cardiac computed tomography (CT) perfusion as compared to the best non-invasive test of blood flow -- cardiac positron emission transmission (PET) perfusion imaging. The primary outcome of the study is to determine the CT perfusion technique with the highest overall diagnostic accuracy measured by the highest area under the receiver operator curve. The investigators will test 4 different CT perfusion techniques. (A) Qualitative, visual inspection of the contrast-enhanced CT images (B) Enhanced voxel distribution analysis (C) Rate of myocardial contrast enhancement analysis (D) Quantitative heart blood flow using a distributed 2-region analysis A second aim is to reduce the radiation dose needed to maintain CT perfusion diagnostic accuracy. Using the CT perfusion data, the investigators will model the minimal number of cardiac cycle radiation exposures needed to keep the diagnostic accuracy similar to the full data set. A third aim is to test the incremental diagnostic accuracy of CT angiography plus CT perfusion to identify regions of low blood flow as compared to PET perfusion alone.
The main purposes of this study is to analyze, in a randomized controlled trial, the effects of an exercise-based cardiac rehabilitation program (i) on biomarkers of endothelial function, (ii) on biomarkers of inflammation, (iii) on autonomic function, and (iv) on arterial stiffness in coronary artery disease patients (CAD). Additionally, the investigators aim to analyze the (v) contribution of age and the changes in traditional risk factors to the modification of the endothelial dysfunction and inflammation, and (vi) the contribution of the changes in inflammatory and endothelial function biomarkers to the modification of autonomic function and arterial stiffness. The investigators hypothesize that exercise training will improve the autonomic function, arterial stiffness and mitigate the endothelial dysfunction and inflammation in CAD patients even in the absence of significant changes in traditional risk factors. Thus, the investigators expect with the present study to promote, develop and expand the knowledge in this field by assessing the impact of exercise on a pool of markers that provide a wide picture of the pathophysiological processes underlying CAD.
During elective percutaneous coronary intervention (PCI), both proximal and distal protection devices are used. The distal occlusion protection device temporarily occludes the vessel distal to the lesion during the intervention, thereby capturing both particular debris and soluble substances released from the lesion such that they can be aspirated and prevented from reaching the coronary microcirculation. Rather than simply discarding the material which is retrieved from use of protection devices, the investigators have recently taken advantage of this situation, sampled the particulate and soluble material and subjected it to a variety of analyses with the ultimate goal to have a better insight into the respective plaque composition and to correlate it to the individual imaging and clinical data. On the basis of such information the investigators aim to better understand the pathophysiology of plaque vulnerability and to possibly predict the clinical development of the individual patient.
Basic studies has showed that sustained use of nitrates might associated with adverse effects on vascular function mediated by an increase in nitrate-induced oxidative stress. But it remains unclear whether oxidative stress increases with endothelial function impairment in patients with coronary artery disease (CAD) during administration of long-term oral nitrates. The investigators evaluated whether administration of long-term isosorbide mononitrate (ISMN) treatment was associated with oxidative stress increase and endothelial function impairment in patients with CAD.
The purpose of the study is to study if coronary angiography cause cognitive dysfunction.