Active clinical trials for "Constriction, Pathologic"

The purpose of this study is to generate clinical data to support the use of GORE® VIABIL® Biliary Endoprosthesis in the endoscopic and percutaneous treatment of benign biliary strictures.

Pyloric stenosis is a condition that develops in infants and that leads to an obstruction of the channel going out of the stomach. This study is being performed to determine if there is an advantage to the laparoscopic approach or the open approach for the surgical correction of the enlarged pylorus.

Pulmonary hypertension is common in patients with aortic stenosis and is associated with worse operative and long-term outcomes. Sildenafil has been shown to reduce pulmonary artery pressure and improve exercise performance in patients with left-sided heart failure, but this has not been tested in patients with aortic stenosis. We hypothesize that Sildenafil will produce a clinically significant decrease in pulmonary artery pressure in patients with severe aortic stenosis. The dose of Sildenafil that produces a significant decrease in pulmonary artery pressure will be safe and well tolerated in patients with and without a depressed ejection fraction.

BACKGROUND: Bifurcated lesions are a challenging subset in percutaneous coronary interventions (PCI). The selection of the type of DES and the technique for stent implantation have not been clarified. The side-branch (SB) is emerging as critical point, accounting for more than a third of the significant restenosis in the DES era. A series of data supports the adoption of a conservative strategy: stenting the main vessel (MV) only and reserving a conservative approach on the SB. Yet, the clinical relevance in terms of inducible ischemia of sub-optimal angiographic result has not been clarified. AIMS OF THE STUDY: The aims of the present study are: to compare in a prospective randomized study the acute 3D angiographic results and the late clinical outcome of Sirolimus-eluting (SES) vs Everolimus-eluting stent (EES) obtained using a provisional TAP-stenting technique. to prospectively assess the clinical relevance (inducible ischemia) of suboptimal angiographic result in the SB after stenting. METHODS TO BE APPLIED: 150 consecutive patients with bifurcated lesions undergoing PCI with the provisional TAP-stenting technique will be randomized to SES or EES implantation. Procedural and post-PCI details will be prospectively recorded. The subgroup of patients in which complete revascularization has been achieved will enter a systematic assessment of inducible ischemia by early and late exercise tests. Off line 3D QCA assessment will be performed and used to divide the study population in 2 groups according to the SB residual stenosis: Group O (optimal SB angiographic result): post-PCI SB area stenosis<50% Group S (sub-optimal SB angiographic result): post-PCI SB area stenosis>50%. PRIMARY STUDY END-POINTS. COMPARISON BETWEEN SES AND EES: SB acute angiographic result; SB trouble; target bifurcation failure. SB-RELATED ISCHAEMIA of Group O vs Group S in patients with complete revascularization: inducible ischemia at the early exercise test or occurrence of early spontaneous ischemia related to the SB.

Severe aortic stenosis is defined with a mean transvalvular pressure gradient (MTPG) > 40mmHg and a calculated aortic valve area of < 1cm2. However, a considerable proportion of patients do have a MTPG < 40mmHg due to a reduced stroke volume (stroke volume indexed to body surface area ≤ 35ml/m2) despite a normal left ventricular ejection fraction (LVEF > 50%). This entity is termed paradoxical low flow low gradient aortic stenosis (PLFLG AS) and is associated with a worse prognosis. ATTR amyloidosis is a disease of the elderly and might coexist in patients with severe aortic stenosis. Case reports and small observational studies suggest that senile ATTR amyloidosis could be frequent but underdiagnosed in patients with aortic stenosis. There is significant overlap between PLFLG AS and cardiac amyloidosis with regard to symptoms, increasing prevalence with age, concentric hypertrophy, impaired diastolic filling of the left ventricle (LV), as well as longitudinal LV dysfunction despite preserved ejection fraction - all features, which lead to a reduction in stroke volume, the underlying mechanism of the low flow condition as observed in PLFLG AS patients.

Prospective, randomized-controlled trial comparing self-expandable metal stent versus ballon dialtation only for the endoscopic treatment of benign strictures related to Crohn´s disease.

That the study will be carried out as it has the protocol instructions, respecting the applicable regulations for clinical investigations with medical devices and following the internationally accepted ethical standards

The primary objective of this double-blind study is to compare the frequency of primary patency at 6 months in patients with stenosis of arteriovenous fistula (AVF) treated either by conventional angioplasty + angioplasty with balloon impregnated with paclitaxel or by conventional angioplasty + angioplasty with placebo balloon (balloon not impregnated with paclitaxel). The other objectives of the study are: To compare the frequency of primary patency at 3 months and 12 months. To compare the rate of restenosis > 50% at the site of angioplasty at 3, 6 and 12 months. To compare, at 3, 6 and 12 months, the proportion of patients with arteriovenous fistula deteriorating back to preoperative flow rate (within 20% of preoperative flow rate). To compare, at 3, 6 and 12 months, the proportion of AVF with a flow rate < 500 ml / min. To compare, at 3, 6 and 12 months, the cumulative rate of thrombosis. To compare, at 3, 6 and 12 months, the medical costs related to direct medical care, initial treatments, monitoring, diagnosis and treatments of complications.

Whether to intervene in asymptomatic patients with severe aortic stenosis and normal left ventricular ejection fraction remains controversial. The investigators therefore try to compare clinical outcomes of elective aortic valve replacement to conventional treatment and watchful waiting strategy in a prospective randomized trial.

Aortic stenosis (AS) is the most frequent valvulopathy in Western countries. The prevalence of AS is constantly increasing due to the aging of the population. Although significant progress has been made in understanding the pathophysiological mechanisms underlying the onset and progression of AS, there is no medical treatment to slow or prevent its progression. The only treatment available is Aortic Valve Replacement (AVR) performed by surgery or by catheterization (TAVI). AS is associated with an increase of post-load which leads the left ventricular myocardium to hypertrophy. Associated with hypertrophy, myocardial fibrosis will gradually develop. Despite interesting data, many unknowns persist and remain to be identified. The aim of the study is to characterize prospectively the left ventricular remodeling and assess its changes after AVR and within 1 year in 500 patients using clinical, biological, echocardiographic and MRI parameters.