Active clinical trials for "Constriction, Pathologic"

This is a single-centre, prospective, observational cohort study focusing on of patients suffering severe aortic valve stenosis (AS) undergoing emergent transcatheter aortic valve implantation (TAVI). AS patients undergoing emergent TAVI always have complicated clinical situations. Therefore, the aims of the study are to collect the incidence and outcomes of emergent TAVI in patients with severe symptomatic AS, to assess the safety and effectiveness of emergency TAVI system for severe AS, and to describe a more practical evidence of emergency TAVI system in severe AS patients.

To evaluate the preliminary efficacy of combination of cutting and drug-coated balloon for the treatment of resistant AVF stenosis.

The purpose of this study is to explore the relationship between the recovery of cerebrovascular morphology and cognitive function before and after surgical treatment in patients with carotid artery stenosis and their preoperative cardiac health status. And combined with preoperative cognitive status, serum markers, and cardiovascular health evaluation indicators, evaluate and predict the possibility of postoperative neurodegenerative diseases and the level of cerebrovascular health in patients.

To evaluate the safety and effectiveness of Grency venous stent system in the treatment of iliac vein stenosis or occlusion.

Atherosclerotic intracranial arterial stenosis (AICAS) corresponds to luminal narrowing of the major intracranial arteries. The prevalence of intracranial atherosclerotic stenosis accounts for 33% to 67% of stroke or transient ischemic attack (TIA) cases in China and other countries in Asia. AICAS is also highly associated with the risk of stroke recurrence. Possible mechanisms of cerebral infarction secondary to AICAS are likely linked with hemodynamic compromise distal to site of stenosis. Computed tomography perfusion (CTP) can be used to evaluate vasoreactivity and cerebrovascular reserve in patients with AICAS and predict future stroke. The parameters of CTP include ①cerebral blood flow(CBF),② cerebral blood volume(CBV) and ③mean transit time(MTT). Relative regional cerebral blood flow (rCBF) was evaluated as the percentage radioisotope counts in the region of interest (ROI) of the affected side against the corresponding ROI in the unaffected contralateral side. Statins can decrease the incidence of transient ischemic attack or ischemic stroke and improve stroke outcome. Few studies focus on the relationship between statins therapy and cerebral perfusion. Whether intensive rosuvastatin therapy compared with standard rosuvastatin therapy can improve hemodynamic situation and cerebral perfusion status in AICAS has not been illustrated. Based on those studies, the investigators hypothesized that intensive rosuvastatin may also improve the symptoms of AICAS not only through enhancing the stability of atherosclerotic plaques, but also its pleiotropic effects. So it can change the hemodynamic status around the plaque and increase cerebral flow in the downstream territory. So in this study the investigators try to analysis statin's impact on the hemodynamic changes as well as the downstream perfusion which is determined by CTP.

To assess the safety and feasibility of Transcatheter Aortic Valve Replacement (TAVR) with commercially available bioprostheses in patients with severe, symptomatic aortic stenosis (AS) who are low-risk (STS score ≤3%) for surgical aortic valve replacement (SAVR).

Cervical stenosis may occur in up to 19% after conization. It is a cause of infertility and amenorrhea. This study will test a new device named DUDA Device ("Dispositivo Uterino para dilatar canal endocervical") placed just after the conization, in order to evaluate the safety, efficacy and quality of life.

First clinical experience on the ACURATE TF™ Transfemoral Aortic Bioprosthesis Implantation in Patients with Severe Aortic Stenosis to collect human data pertaining to the safety and performance of the device from three different cohorts

The purpose of this investigation is to collect data pertaining to the safety and performance of the ACURATE neo (TM) Aortic Bioprosthesis as implanted with the ACURATE neo (TM) TA Transapical Delivery System. This device is intended for treatment of subjects with severe aortic stenosis (AS) who have high risk for conventional aortic valve replacement (AVR) surgery. The ACURATE neo (TM) Aortic Bioprosthesis is intended for use via minimally-invasive transapical implantation in a well-defined population.

The purpose of this study is to evaluate safety of the study device and study device performance in patients presenting with severe aortic stenosis who are considered to be high risk for open surgical repair.