nitinol and Venous-Insufficiency

The aim of the study was to investigate venous patency and clinical outcomes for endovascular treatment of iliofemoral venous obstruction in patients with post-thrombotic syndrome (PTS) and non-thrombotic iliac vein lesion (NIVL) with dedicated self-expanding nitinol stents.. Data were collected from the prospective Swiss Venous Stent Registry, enrolling consecutive patients with a standardized follow-up procedure since January 2008. Patency was evaluated by duplex sonography and clinical outcome by various scores including the Villalta score at baseline, three, six, and 12 months, and then annually after endovascular therapy.. Overall, 93 patients (64 PTS, 29 NIVL) were analysed. Mean follow-up time was 20 ± 16 (range 3-70) months. A total of 11 (12 %) patients had a stent occlusion, all of which occurred in the PTS group, and 13 (14 %) patients had a symptomatic stent stenosis. Primary patency was 79 % (95 % CI 68-87 %) at 12 months and 72 % (95 % CI 59-82 %) at 24 months. In PTS patients, primary patency at 12 months was 75 % (95 % CI 61-84 %) vs. 89 % (95 % CI 63-97 %) in NIVL patients (p = 0.10). Secondary patency at 24 months was 94 % (95 % CI 84-98 %) in PTS and 100 % in NIVL, p = 0.19). Overall, 62 (67 %) patients were free from PTS at the latest follow-up with a Villalta score < 5 points. Predictive factors for the loss of primary patency were stents placed below the inguinal ligament (OR 2.59, 95 % CI, 0.99-6.84, p = 0.05).. In symptomatic patients with chronic iliofemoral vein obstruction, endovascular therapy with self-expanding nitinol stents was associated with favourable patency rates and clinical improvement in the majority of patients.

Topics: Adult; Aged; Alloys; Chronic Disease; Endovascular Procedures; Female; Femoral Vein; Humans; Iliac Vein; Male; Middle Aged; Postthrombotic Syndrome; Prosthesis Design; Registries; Self Expandable Metallic Stents; Switzerland; Time Factors; Treatment Outcome; Ultrasonography, Doppler, Duplex; Vascular Patency; Venous Insufficiency

The study aimed to test a Nitinol(®)-based vein cuff model for external banding valvuloplasty.. In 12 adult minipigs, the vena jugularis externa was covered for 42 days by a cuff with an inner diameter adapted to the outer vein diameter in supine position. By changing from supine into prone position hypostatically vein dilation was induced to simulate varicose vein dilation. Cuff position and the inner diameter of the vein lumen under the cuff were examined by computer tomography scanning. Also, histological analysis of the vein wall within the cuff was performed.. The preset tubular shape of the cuff and the cuff position did not change in both prone and supine position, but due to fibrosis the luminal vein diameter within the cuff was decreased (P < 0.01) already after 21 days.. A foreign body response resulted in a fibrous capsule covering the cuff which might limit cuff functionality.

Topics: Alloys; Anesthesia; Animals; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Female; Foreign-Body Reaction; Swine; Swine, Miniature; Time Factors; Tomography, X-Ray Computed; Varicose Veins; Venous Insufficiency

Topics: Aged, 80 and over; Alloys; Angiography, Digital Subtraction; Angioplasty, Balloon; Arterial Occlusive Diseases; Equipment Failure; Female; Femoral Artery; Follow-Up Studies; Humans; Magnetic Resonance Angiography; Stents; Ultrasonography, Doppler, Color; Varicose Ulcer; Venous Insufficiency