Active clinical trials for "Constriction, Pathologic"

The aim of the work is to; elucidate how the presence of carotid stenosis influence the pattern of stroke and also how it interact with other risk factors for stroke. Also identify predictors of intracranial stenosis and outcome in patients with carotid stenosis with or without intracranial stenosis.

This study aims to evaluate whether baseline 18F-sodium fluoride uptake activity at aortic valve could predict aortic stenosis progression in moderate aortic stenosis. Patients with moderate aortic stenosis are enrolled and underwent baseline evaluation including 18F-sodium fluoride PET/CT. After 1 year, all the participants underwent follow-up echocardiography. The study design is an observational trial. Primary endpoint was a change in mean pressure gradient along the aortic valve as assessed by echocardiography at 1 year. Secondary endpoints include changes in aortic valve area, and symptom occurrence.

Atherosclerosis is the major contributor for the morbidity and mortality for the variety of cardiovascular diseases. Aortic calcification on x-ray is a marker for arterial atherosclerosis and an independent prognostic factor for the morbidity and mortality from a cardiovascular event. Carotid artery stenoses is the current accepted indication for interventional treatment of carotid artery, for the prevention of embolic event, while other arterial atherosclerosis indication, is for hemodynamic disturbance and ischemic outcome. This research will try to find whether incidental aortic calcification can predict carotid artery stenosis. Two groups will be chosen: group A - patients who had CT scan in the hospital (for different indications); Group B - patients (not from the first group) who have a significant carotid artery stenosis who are indicated for interventional treatment. The data to analyze: Group A - Patients with aortic calcification, carotid artery stenosis, and patients with both Group B - Patients who have aortic calcification Comparison of the populations within the group and among the two will show if a significant correlation between aortic calcification and carotid artery stenosis exist.

Pathophysiology of Aortic Valve Stenosis remains poorly known. The aim of the present study is to identify genetic factors involved in this disease using a case control trial design.

The population of the US is aging. They remain more active and place greater demands on their musculoskeletal system. A key problem is that pain and disability of age related spinal disorders will increase. Problems such as Degenerative Lumbar Spondylolisthesis, Degenerative Disk Disease, Spinal Stenosis and Degenerative Scoliosis are age related problems that are treated with spinal fusion when non-operative treatment fails. Traditional open surgery poses significant risk for patients in this age group. The use of minimally invasive spinal surgery techniques provides an opportunity to treat these patients with less morbidity than traditional open surgery.

In patients with asymptomatic aortic stenosis (AS), the prognostic value of reduced left ventricular (LV) ejection fraction is well known. Consequently, there is class I indication for surgery in these patients when LV ejection fraction <50%. However, there is growing evidences suggesting that subclinical LV dysfunction, and more particularly longitudinal myocardial dysfunction, may be a powerful early predictor of outcome, even when LV ejection is still preserved. In asymptomatic AS patients with LV ejection fraction >50%, a reduced LV global longitudinal strain, as assessed using speckle tracking imaging with transthoracic echocardiography, may be an accurate marker to identify early subclinical LV dysfunction and thus, to improve the risk stratification, the management and the timing of surgery. Several mono-centric observational small studies recently reported results emphasizing the role of LV global longitudinal strain in AS patients. Therefore, a meta-analysis may be conducted and may provide meaningful data. The investigators hypothesized that LV global longitudinal strain is a determinant of outcome in asymptomatic patients with AS and preserved LV ejection fraction.

Register of treatment of unprotected left main coronary artery stenosis in Andalucia (RETRATO).

The primary purpose of this study is electronic data collection of arterial pressure waveform signals in patients with Aortic Stenosis. The collected digital pressure waveform data will be used to assess the feasibility of using the arterial pressure signal as a decision support tool for early detection of aortic stenosis conditions. Furthermore we evaluate hemodynamic parameters before and after valve repair and its correlation with outcome.

This study will use PBV technique to quantitatively assess the improvement of renal perfusion before and after endovascular treatment (EVT) of renal artery stenosis.

Angina pectoris is the most common clinical manifestation of coronary heart disease（CHD）, which is the main feature of chest pain caused by transient myocardial ischemia. Chronic stable angina pectoris is the degree, frequency, nature and cause of angina pectoris in patients with no significant change in a few weeks. The disease incidence is complex, difficult to diagnosis and treatment, clinical should be combined with various inspection methods for diagnosis and differential diagnosis. Fractional flow reserve of computerized tomographic scanning (FFRCT ) allows computerized tomographic scanning（CT） to scan the determination of coronary blood flow and blood pressure in the heart at rest and hyperemia, but no need to additional check or drugs. This technique has been used for noninvasive fractional flow reserve (FFR) in the calculation, assuming normal artery, calculated by the ratio of the maximum blood flow and blood flow of coronary artery stenosis of an artery. Along with the development and progress of computational fluid dynamics, in the resting state by computed tomographic angiography of coronary artery(CCTA) image data based, simulation of coronary artery maximal hyperemia and according to the 3-dimensional model of the traditional method of reconstruction of coronary arterial tree and ventricular muscle structure, and in order to calculated coronary blood flow and pressure. FFRCT is a novel non-invasive examination method, using computed tomographic angiography of coronary artery image data can be calculated FFR, and preliminary study proved that it has a high degree of correlation with traumatic FFR. Therefore, this study aims to evaluate the correlation between the degree of coronary stenosis and the grading of angina pectoris by noninvasive means --FFRCT, in order to provide a new idea for the diagnosis and differential diagnosis of coronary heart disease.