Active clinical trials for "Constriction, Pathologic"

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.

The loss of sodium during infancy causes long term changes in sodium intake. Human research shows that the loss of maternal sodium during pregnancy and neonatal after birth causes an increase sodium intake during childhood. A study that examined sodium intake among infants that were treated with diuretics during the post-natal period found changes in sodium intake compared to controls. In this study we will test sodium intake in young children who have suffered from vomiting due to Hypertrophic Pyloric stenosis during early infancy.

Recent studies have shown that optimal IVUS criteria defining the functional significance (FFR < 0.8) of intermediate coronary stenoses is different according to their locations of the coronary tree. Herein, the investigators performed this study to validate these results and to generalize the IVUS criteria defining functional significance of intermediate coronary stenosis in a different location of coronary tree in a larger sample size.

The purpose of this study is to evaluate the feasibility of acquisition of coronary blood flow velocity signals over the whole length of the LAD with transthoracic pulsed Doppler, and to evaluate the diagnostic power of the transthoracic Doppler analysis package for detecting and estimating the degree of coronary artery stenosis. Finally we hope to optimize the currently available analysis package on the basis of the comparison of the Doppler with the angiographic stenosis results and evaluation.

A novel, image-based model for estimation of the pressure gradient across stenosed aortic valves is compared against invasively measured pressure gradients from clinical routine.

Evaluation of the perforated punctal plugs after implantation in cases of punctal stenosis regarding position and patency in the early postoperative period (during the first operative weak)

Trimethylamine N-oxide (TMAO) has recently gained increasing scientific interest in the field of cardiovascular disease, including its role in cell protection against osmotic and hydrostatic stress. Aortic stenosis (AS) is the most common valvular heart disease, affecting about 7.6 million people over 75 years of age in North America and Europe alone. We hypothesized that TMAO plays a role in protection of the cardiomyocytes against pressure overload in patients with AS. The primary aim of this study is to assess the correlation between the serum and urine TMAO concentration, and (i) echocardiographic, (ii) biochemical and (iii) histopathological parameters of heart failure in patients with severe AS. The secondary aim of this study is to evaluate a correlation between the baseline TMAO concentrations and the post-treatment clinical status, as well as the post-treatment echocardiographic and biochemical parameters.

Urethral stenosis has a recurrent character. The clean intermittent self-catheterization can be proposed for repeat stenosis. This study seeks to explore the tolerance of clean intermittent self-catheterization in the evolution of urethral stenosis after urethrotomy.

To analyze the prevalence and impact on the prognosis of amyloidosis due to transthyretin in patients with severe aortic stenosis who undergo percutaneous aortic valve implantation.