View clinical trials related to Ischemia.
Filter by:Coronary artery disease (CAD) is the leading cause of death worldwide. Patients with severe CAD are often treated with coronary artery bypass grafting (CABG). Novel treatment strategies need to be pursued to respond to the continuous increase in the risk profile of contemporary CABG patients. Surgical myocardial revascularization is commonly performed with the use of cardiopulmonary bypass (CPB). Neurological impairment following CABG may take on the form of a new-onset motor deficit or postoperative cognitive dysfunction. The former is rare, but potentially devastating. Conversely, declines in attention, memory and fine motor skills can frequently be documented. Ischemic preconditioning is a phenomenon of an endogenous protective response to organ ischemia, which is triggered by brief cycles of nonlethal ischemia and reperfusion in tissues known to be more resistant to ischemic insults. In clinical practice remote ischemic preconditioning (RIPC) is achieved by inflicting short periods of ischemia with intermittent restitution of flow to the upper extremity. This intervention has been shown to be effective in the reduction of myocardial injury in cardiac surgical patients. The hypothesis tested in this research proposal is that RIPC will decrease the extent of postoperative neurological injury following CABG. In this research project, 70 patients scheduled for an elective CABG will be recruited at a single center. They will be randomly allocated to either undergo RIPC (intervention arm) or a sham procedure (control arm). Inflating a blood pressure cuff to 200 mmHg for 5 min will induce RIPC, thereby inducing a brief period of ischemia. This will be followed by a 5-minute arm reperfusion. In total, three cycles of arm ischemia and reperfusion will be induced in this fashion. All patients will undergo pre- and post-procedural magnetic resonance imaging (MRI) of the brain, as well as neurocognitive testing. The array of MRI tools that will be used for the quantification of brain injury will include fluid attenuated inversion recovery, diffusion weighted and susceptibility weighted imaging, coupled with resting state functional MRI. The investigators aim to determine whether RIPC can reduce the adverse impact of CPB on neurological outcome as evaluated by MRI detectable brain ischemia and neurocognition.
Specific cardiovascular diseases, such as stroke and heart attack, have been shown to vary by ethnic group. However, less is known about differences between ethnic groups and a wider range of cardiovascular diseases. This study will examine differences between ethnic groups (White, Black, South Asian and Mixed/Other) and first lifetime presentation of twelve different cardiovascular diseases. This information may help to predict the onset of cardiovascular diseases and inform disease prevention strategies. The hypothesis is that different ethnic groups have differing associations with the range of cardiovascular diseases studied.
The study seeks to determine the accuracy of using anatomic and physiologic information measurable by computed tomography features of stenosis, plaque, fractional flow reserve-CT and to compare this measure to stress testing for the detection of myocardial ischemia against the gold standard of cardiac catheterization with fractional flow reserve. The hypothesis of this proposal is that integrating anatomic plaque features with physiologic fractional flow reserve-CT will optimize identification of coronary lesions that are ischemia-causing by computed tomography .
This study will compare two ways of treatment for acute ischemic stroke: an endovascular treatment (EVT), defined as intraarterial thrombolysis and/or mechanical thrombectomy as a first choice treatment versus intravenous thrombolytic therapy (IVT) only or followed by EVT in patients with acute ischemic stroke due to a main brain artery occlusion within 4.5 hours after onset. Patients treated with IVT only or with IVT followed by EVT will be analyzed separately.
Among the current myocardial CT perfusion techniques, dynamic CT perfusion technique is most advantageous in obtaining information on myocardial blood flow and volume. However, dynamic CT perfusion technique involves higher radiation dose than static CT techniques. Patients have to take a breath hold during 30 seconds with current dynamic CT perfusion protocol. If patients cannot hold their breath, anterior or inferior myocardium might be excluded due to limited scan coverage of a 128-slice dual-source CT scanner. Reduction of scanning duration of dynamic CT perfusion may not only reduce radiation exposure, but also make patients more comfortable. Therefore, the investigators intended to propose a modified scan protocol with shorter scan duration and compare diagnostic accuracy of a modified scan protocol with the current scan protocol.
Vascular endothelial growth factor (VEGF) and Endostatin (ES) participate angiogenesis after cerebral ischemia. Circulating endothelial progenitor cells (EPCs) also play a crucial role in neovascularization and tissue repair after acute ischemic stroke (AIS). The investigators sought to compare the expression of VEGF and ES in serum and the circulating EPCs in patients after AIS with that of healthy control subjects. The investigators obtained peripheral blood and serum samples from study subjects. EPCs in blood samples from AIS patients and healthy controls were quantified by flow cytometry 1 day, 3 days, 5 days and 7 days after AIS. VEGF and ES were measured by enzyme linked immunosorbent assay at the same time points. The relation between them and the relation of them to prognosis of such patients with acute ischemic stroke were assessed.
Patients after ischemic stroke are at high risk of recurrent cardiovascular events and of developing post-stroke complications. There is a substantial gap between risk factor management in real life and that recommended by international guidelines. Stroke Card is a multifaceted comprehensive post-stroke disease management program to detect and treat complications and optimize secondary prevention. The investigators hypothesize that, compared to standard care, Stroke Card will lead to an at least 33.3% risk reduction in recurrent cardiovascular events and improve health-related quality-of-life.
Purpose 1. To validate 2 -day loop recording ( R.Test Evolution 4 ) to 2 -day Holter recording (gold standard) for the detection of atrial fibrillation of ≥ 30 seconds duration in a consecutive population of patients with stroke or transient ischemic attack (TIA). 2. To determine whether short run of atrial fibrillation (< 30s ) or the presence of many supraventricular extrasystoles detected on Holter recording, is associated with risk of re-stroke in a consecutive population of patients with stroke or TIA . 3. To test whether a 7-day Loop Recording (R -test) detects more patients with atrial fibrillation than 2 days of Holter recording in a consecutive population of patients with stroke or TIA.
Around 7500 neonates born yearly in the United States have complex congenital heart disease that require surgical repair in the first few days of life. The complexity of the surgical repair requires long periods of cardiopulmonary bypass (CPB) and the use of intermittent periods of low flow or complete circulatory arrest. The immature neonatal vital organs are more prone to the complications of the cardiopulmonary bypass circulation, namely ischemia/reperfusion (I/R) injury and systemic inflammatory response. Inhaled nitric oxide (NO) is used frequently in neonates for the treatment of pulmonary hypertension, Additionally, many studies have shown that NO has an anti-inflammatory effect by reducing I/R injury and endothelial dysfunction. The purpose of this pilot study is to assess the efficacy of NO administration via the CPB circuit in attenuating the CPB induced I/R injury and systemic inflammatory reaction in neonates undergoing repair of complex congenital heart defects. Specific goals will be to demonstrate that NO use via CPB will: - Decrease markers of I/R injury and systemic inflammatory response. - Decrease platelet activation leading to reduced postoperative bleeding and transfusion requirements. - Decrease postoperative organ dysfunction, and hence decrease operative mortality and postoperative morbidity. Twelve neonates undergoing repair of complex congenital heart defects will receive NO via the CPB circuit, for the duration of surgery. They will be compared to a control group of 12 similar patients. Serum levels of different ischemic reperfusion injury and inflammatory markers will be measured at different time points after surgery and will be correlated with different end organ function tests and clinical course in the postoperative period. The results will be compared between the two groups to try to determine the clinical benefit of NO administration through CPB circuit.
The purpose of this study is to determine whether remote ischemic preconditioning with postconditioning (RIPC+RIPostC) reduces myocardial injury and improves clinical outcomes in heart transplantation surgery.