nitinol and Postthrombotic-Syndrome

Chronic obstruction of the common femoral vein in patients with post-thrombotic syndrome after iliofemoral or iliocaval deep vein thrombosis has remained a challenge for endovascular treatment. The patency rates and clinical outcomes of laser-cut and braided nitinol stents extending to the common femoral vein have not yet been studied.. From the Swiss and Arnsberg Venous Stent Registries, we included 150 patients with post-thrombotic syndrome (mean age, 44 ± 16 years; 48% women) with laser-cut (n = 101) or braided nitinol (n = 49) stents placed into the common femoral vein across the inguinal ligament. Routine follow-up included duplex ultrasound examinations and assessment of clinical scores. The primary study outcomes were the primary and secondary patency rates at 12 months.. Overall, the mean number of implanted stents was 2.6 ± 1.7. The proximal stent landing zone was the inferior vena cava in 32 patients (21%), the iliac vein in 106 patients (76%), and the common femoral vein in 5 patients (3%). The primary patency rate was 67.3% (95% confidence interval [CI], 58.0%-76.6%) in the laser-cut group and 86.7% (95% CI, 75.3%-98.1%) in the braided stent group (log-rank, P = .016). The corresponding secondary patency rates were 93.9% (95% CI, 89.2%-98.6%) and 100% (log-rank, P = .10). The median improvement in the Villalta score from baseline to the latest follow-up was 4 points (interquartile range, 2-6 points), without significant differences between the two groups. Symptomatic common femoral vein stent fractures were observed in four patients (4%) with laser-cut stents but in no patient with braided stents.. The use of braided nitinol stents for common femoral vein obstruction appeared to be associated with favorable primary patency rates at 12 months compared with laser-cut nitinol stents. Further studies are needed to confirm that braided nitinol stents remain patent and might be less prone to fractures in the long term.

Topics: Adult; Alloys; Angioplasty, Balloon; Female; Femoral Vein; Germany; Humans; Male; Middle Aged; Postthrombotic Syndrome; Prosthesis Design; Registries; Retrospective Studies; Self Expandable Metallic Stents; Switzerland; Time Factors; Treatment Outcome; Ultrasonography, Doppler, Duplex; Vascular Patency

Thrombophilia is a prothrombotic condition that increases the risk of venous thromboembolism. It is unclear whether the presence of thrombophilia alters the clinical outcomes after deep venous stenting. The aim of the present study was to examine the relationship between thrombophilia and outcomes after stenting for post-thrombotic syndrome.. Consecutive patients (2012-2017) receiving a nitinol venous stent for chronic post-thrombotic venous occlusive disease with a minimum of 18 months of follow-up in one center using the same anticoagulation protocol were included. The clinical history and thrombophilia testing results were reviewed. The outcomes were stent patency, which was assessed using duplex ultrasonography at 24 hours, 2 and 6 weeks, 3 months, 6 months, and annually thereafter; and reinterventions, which were performed when the stent diameter was <50% or occluded.. Of the 136 patients who had undergone intervention, 55 (40%) had had a provoked deep vein thrombosis (DVT) and 81 (60%) had had an unprovoked DVT and had therefore undergone thrombophilia testing. Of the 81 patients, 38 (47%) had had either inherited (n = 19; 50%) or acquired (n = 19; 50%) thrombophilia. Of the 136 patients who had undergone stenting, 68 had required reintervention (50%) during follow-up to maintain stent patency. Of the 55 patients with a provoked DVT, 29 (53%) had required reintervention. Of the 81 patients with an unprovoked DVT, 39 (48%) had required reintervention (P = .420). Of the 38 patients with unprovoked DVT and thrombophilia, 17 (45%) had required reintervention. Of the 43 patients with unprovoked DVT and no thrombophilia, 22 (51%) had required reintervention (P = .766). The cumulative patency rate was 80% for patients with provoked DVT and 88% for those with unprovoked DVT (P = .193). The presence of thrombophilia was not associated with patency loss (92% cumulative patency for patients with thrombophilia and 84% for patients without thrombophilia; P = .307).. Using our anticoagulation protocol, patients with and without thrombophilia had similar clinical outcomes after deep venous stenting and should not be excluded from iliofemoral venous stenting. We found no significant differences in outcomes in conjunction with appropriate postoperative anticoagulation therapy.

Topics: Adult; Alloys; Anticoagulants; Female; Femoral Vein; Humans; Iliac Vein; Male; Middle Aged; Postthrombotic Syndrome; Prosthesis Design; Reoperation; Retrospective Studies; Stents; Thrombophilia; Treatment Outcome; Vascular Patency

Topics: Alloys; Chronic Disease; Female; Femoral Vein; Humans; Iliac Vein; Male; Postthrombotic Syndrome; Registries; Retrospective Studies; Stents; Treatment Outcome; Vascular Patency

Topics: Alloys; Humans; Iliac Vein; May-Thurner Syndrome; Postthrombotic Syndrome; Retrospective Studies; Stents; Treatment Outcome; Vascular Patency

Topics: Adult; Alloys; Endovascular Procedures; Female; Humans; Iliac Vein; Male; Middle Aged; Postthrombotic Syndrome; Quality of Life; Retrospective Studies; Stents; Treatment Outcome; Vascular Patency

 Patients with postthrombotic syndrome (PTS) treated with stents are at risk of stent thrombosis (ST). The incidence of ST in the presence and absence of anticoagulation therapy (AT) is unknown. Risk factors are not well understood..  From the prospective Swiss Venous Stent registry, we conducted a subgroup analysis of 136 consecutive patients with PTS. Incidence of ST was estimated from duplex ultrasound or venography, and reported for the time on and off AT. Baseline, procedural, and follow-up data were evaluated to identify factors associated with ST..  Median follow-up was 20 (interquartile range [IQR] 9-40) months. AT was stopped in 43 (32%) patients after 12 (IQR 6-14) months. Cumulative incidence of ST was 13.7% (95% confidence interval [CI] 7.8-19.6%) and 21.2% (95% CI 13.2-29.2%) during the first 6 and 36 months, respectively. The time-adjusted incidence rate was 11.2 (95% CI 7.7-16.2) events per 100 patient-years, 11.3 (95% CI 7.3-17.3) for the period on, and 11.2 (95% CI 5.3-23.6) for the period off AT. May-Thurner syndrome (MTS) was associated with decreased incidence of ST (hazard ratio [HR] 0.37, 95% CI 0.15-0.91), whereas age < 40 years (HR 2.26, 95% CI 1.03-4.94), stents below the common femoral vein (HR 3.03, 95% CI 1.28-7.19), and postthrombotic inflow veins (HR 2.92, 95% CI 1.36-6.25) were associated with increased incidence..  The 6-month incidence of ST was considerably high. Beyond 6 months, consecutive annual incidence rates persisted at 4.1 and 3.4% per year thereafter. Patients with higher incidence of ST were younger, had stents below the common femoral vein, postthrombotic leg inflow veins, and less often MTS. Incidence rates for the period on and off AT must be interpreted with caution..  The study is registered on the National Institutes of Health Web site (ClinicalTrials.gov; identifier NCT02433054).

Topics: Adult; Alloys; Anticoagulants; Endovascular Procedures; Female; Femoral Vein; Fibrinolytic Agents; Follow-Up Studies; Humans; Iliac Vein; Incidence; Male; Middle Aged; Phlebography; Postthrombotic Syndrome; Registries; Risk Factors; Stents; Switzerland; Thrombosis; Treatment Outcome; Vena Cava, Inferior

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

Deep venous stenting has become the primary treatment option for chronic venous obstructive disease, both for iliac vein compression and post-thrombotic venous lesions. Until recently, only stents aimed at arterial pathology were used, because no dedicated venous stents were available. However, three such stents have now become available. These venous stents are characterized by increased length, diameter, flexibility, and radial force. This study reports an early experience with one of these devices; the sinus Venous stent (OptiMed GmbH, Ettlingen, Germany).. Between March 2012 and July 2014, 75 patients were treated with the sinus Venous stent: 35 cases of iliac vein compression syndrome and 40 cases of unilateral chronic obstruction in post-thrombotic syndrome (PTS). Diagnosis of relevant obstruction was made using clinical evaluation, duplex ultrasound, and magnetic resonance venography. Patency during follow up was assessed with duplex ultrasound. Clinical improvement was assessed by VCSS, Villalta score, rate of ulcer healing, and improvement of venous claudication.. The cumulative patency rates at 3, 6, and 12 months were 99%, 96%, and 92%, respectively. The cumulative assisted primary patency rates were 99% at 3, 6, and 12 months. The cumulative secondary patency rate at 12 months was 100%. Differences exist in patency rate between the subgroups of non-thrombotic and post-thrombotic, with the first showing no re-occlusions. All re-thromboses in the PTS group were treated by ancillary treatment modalities. VCSS and Villalta score decreased significantly after stenting, as did venous claudication. Morbidity was low without clinically relevant pulmonary embolism, and mortality was nil. Although two out of seven ulcers healed temporarily, no ulcer remained healed at 12 months follow up.. Short-term clinical results using the sinus Venous stent are excellent, with significant symptom reduction, low morbidity rates, and no mortality. Loss of stent patency is seen less often compared with arterial stents described in the literature.

Topics: Adolescent; Adult; Aged; Alloys; Angioplasty, Balloon; Chronic Disease; Female; Humans; Iliac Vein; Intermittent Claudication; Kaplan-Meier Estimate; Leg Ulcer; Magnetic Resonance Angiography; Male; May-Thurner Syndrome; Middle Aged; Netherlands; Phlebography; Postthrombotic Syndrome; Prosthesis Design; Recurrence; Stents; Tertiary Care Centers; Time Factors; Treatment Outcome; Ultrasonography, Doppler, Duplex; Vascular Patency; Wound Healing; Young Adult