Venous In-stent Thrombosis Treated by Ultrasound Accelerated Catheter Directed Thrombolysis

The Safety and Efficacy of ZelanteDVT™ Catheter Rheolytic Thrombectomy in the Treatment of Patients with Iliac Vein Stent Thrombosis

BACKGROUND

To examine the safety and efficacy of ZelanteDVT™ catheter rheolytic thrombectomy in the treatment of patients with iliac vein stent thrombosis.

METHODS

A retrospective analysis method was conducted by means of collecting the data of 32 patients who had completed the treatment of iliac vein stent thrombosis with ZelanteDVT catheter rheolytic thrombectomy from March 2019 to March 2023. Data on clinical characteristics, technical success, clinical success, complications, and early follow-up were analyzed.

RESULTS

The technical success rates were 100%, intraoperatively, in which 22 cases were improved to thrombus clearance Grade II (50-90%), 10 were Grade III (>90%). There were 21 cases treated with subsequent catheter-directed thrombolysis, and the average urokinase administration of (120.90 ± 29.63)∗10ˆ4 units. The clinical success rates were 100% and the swelling of the affected limbs were significantly improved, a significant difference in the pre/postoperative between-thigh circumference difference [(5.16 ± 1.08) vs. (1.75 ± 0.84), P < 0.000]. The pre/postoperative Venous Clinical Severity Score was [(12.94 ± 1.70) vs. (7.44 ± 1.31), P < 0.000]. No serious complications occurred during the perioperative period. The postoperative and 12-month stent patency rate was 100.00% (32/32) and 71.88% (23/32), respectively.

CONCLUSIONS

The ZelanteDVT catheter rheolytic thrombectomy seems to have a promising application prospect for the treatment of patients with iliac vein stent thrombosis.

Endovascular mechanical thrombectomy of iliofemoral venous stent occlusion with the novel RevCore thrombectomy system: case reports and literature review

Venous in-stent restenosis is not completely understood, and the currently available treatment is usually unsatisfactory. We describe the cases of two patients treated with the RevCore thrombectomy system (Inari Medical), designed for venous in-stent thrombosis. Case 1 involves a 62-year-old woman with post-thrombotic syndrome from iliac vein stent placement 15 years earlier. Case 2 describes a 30-year-old woman with post-thrombotic syndrome from recurrent iliac vein stent occlusion, despite therapeutic anticoagulation. Both patients had previous recanalization attempts at outside facilities that were unsuccessful. The RevCore system was safe and feasible in these initial cases, and more studies are warranted.

Mechanical thrombectomy of venous in-stent thrombosis with the novel RevCore thrombectomy system: A report of 2 cases

In-stent thrombosis (IST) is a common venous stent complication. Acute IST warranting intervention can generally be treated with catheter-directed thrombolysis or aspiration thrombectomy. However, thrombosed stents often have chronic-appearing components that pose a significant treatment challenge as the thrombus firmly adheres to the stent and vessel wall and becomes resistant to thrombolytics and aspiration thrombectomy. Alternate treatment options such as venoplasty, stent relining, and medical management do not remove existing IST but rather remodel the lumen with limited long-term efficacy. This report details 2 cases of chronic-appearing IST successfully debulked with the novel RevCore Thrombectomy System. RevCore, designed to mechanically liberate acute to chronic IST via an expandable nitinol coring element, achieved substantial luminal gain and sustained patency in both patients.

Successful Secondary Endovascular Intervention in Pediatric Patients with Venous Thromboembolic Events

BACKGROUND

 In the past, pediatric patients with venous thromboembolic events (VTE) were treated with low-molecular-weight heparin (LMWH) which was successful in around 70% of the cases. However, anticoagulation alone might not restore patency in all patients, and advanced therapeutic options to prevent postthrombotic syndrome are needed. During recent years, endovascular interventions have become a treatment option for pediatric patients with persistent thrombotic occlusion, not only in life- or limb-threatening VTE.

METHODS

 We evaluated 12 consecutive patients (11-17 years) with newly diagnosed VTE being treated at our department during the last 4 years (2017-2020). In case follow-up examination showed persistent venoocclusion under anticoagulation, patients received secondary interventional therapy like recanalization, percutaneous transluminal angioplasty with or without catheter-directed thrombolysis, and stenting. Patients with no clinical signs of venoocclusion or regredient thrombosis in imaging examination received anticoagulation alone.

RESULTS

 Six of 12 (50%) patients underwent catheter intervention. Median time from diagnosis to intervention was 4 months (0-12 months). Reintervention was necessary in one (8%) case and complete recanalization failed in one (8%) case. There were no major bleeding events or other major postinterventional complications, no acute or late local recurrence, and all patients reported clinical improvement after the procedure.

CONCLUSION

 If endovascular intervention is used in teenage patients with persistent symptomatic VTE, reduction of postthrombotic symptoms is possible, even if intervention is performed secondary to failure of anticoagulation. Multidisciplinary treatment decisions can be based on the clinical course and follow-up imaging.

Reduced External Iliac Venous Blood Flow Rate Is Associated with Asymptomatic Compression of the Common Iliac Veins

Background and Objectives: Compression of the common iliac veins (CIV) is not always associated with lower extremity symptoms. This study analyzed this issue from the perspective of patient venous blood flow changes using quantitative flow magnetic resonance imaging. Materials and Methods: After we excluded patients with active deep vein thrombosis, the mean flux (MF) and mean velocity (MV) of the popliteal vein, femoral vein, and external iliac vein (EIV) were compared between the left and right sides. Results: Overall, 26 of the patients had unilateral CIV compression, of which 16 patients had symptoms. No significant differences were noted in the MF or MV of the veins between the two sides. However, for the 10 patients without symptoms, the EIV MF of the compression side was significantly lower than the EIV MF of the non-compression side (p = 0.04). The receiver operating characteristic curve and chi-squared analyses showed that when the percentage difference of EIV MF between the compression and non-compression sides was ≤-18.5%, the relative risk of associated lower extremity symptoms was 0.44 (p = 0.016). Conclusions: If a person has compression of the CIV, a decrease in EIV blood flow rate on the compression side reduces the rate of symptom occurrence.

Comparison of ultrasound-accelerated versus conventional catheter-directed thrombolysis for deep vein thrombosis: A systematic review and meta-analysis

BACKGROUND

Recent in vitro and clinical studies have shown that ultrasound-accelerated catheter-directed thrombolysis (USACDT) can accelerate thrombolysis. Therefore, in this meta-analysis, we aimed to compare the efficacy and safety of USACDT with conventional catheter-directed thrombolysis in patients with deep vein thrombosis.

METHODS

A systematic search of the following electronic databases was performed from their dates of inception to 20 June 2020: MEDLINE, Scopus, Google Scholar, CINAHL, Cochrane Library, and EMBASE. All randomized controlled trials that directly compared the complications and efficacy of USACDT and conventional catheter-directed thrombolysis in patients with deep vein thrombosis were identified. The statistical analysis was performed using comprehensive meta-analysis software.

RESULTS

Finally, 18 studies with a total of 597 participants were included in our meta-analysis according to the eligibility criteria. Pooled proportion of USACDT success in patients with deep vein thrombosis was 87.8% (18 studies; 95% CI: 83.1-91.3). Success rate was significantly higher in USACDT treatment than in conventional catheter-directed thrombolysis treatment (seven studies; OR: 2.96; 95% CI: 1.69-5.16; P < 0.01)). Although the mean infusion time was higher in catheter-directed thrombolysis treatment compared to USACDT treatment, this difference was not statistically significant (three studies; MD: -1.46; 95% CI: -3.25-0.32; P = 0.10). Moreover, pooled rate of complications was lower in USACDT than catheter-directed thrombolysis which was not statistically significant (seven studies; OR: 0.49; 95% CI: 0.13-1.76; P = 0.27).

CONCLUSION

This meta-analysis revealed that USACDT significantly increased the success rate of thrombolysis compared to conventional catheter-directed thrombolysis. Furthermore, USACDT was associated with lower rate of complication and infusion time. Taken together, these findings confirm the superiority of this novel intervention over conventional catheter-directed thrombolysis in treatment of patients with deep vein thrombosis.

Stent characteristics of 32 patients with early (<14 days) iliofemoral stent occlusion

OBJECTIVE

Endovascular treatment with percutaneous transluminal angioplasty and stenting has quickly gained popularity for treatment of deep venous obstructive disease. Early thrombosis after stenting in iliofemoral veins is uncommon. The treatment and analysis of the underlying factors leading to the rethrombosis of stents placed in the previous 14 days are reported in this study.

METHODS

Patients diagnosed with early in-stent thrombosis after iliofemoral stenting were reviewed in this retrospective analysis. Patients with acute occlusion were routinely treated by catheter-directed thrombolysis (CDT), and the underlying causes of early occlusion were identified during the procedure. After successful CDT procedures, patients received additional interventions (percutaneous transluminal angioplasty with or without stenting) if indicated.

RESULTS

A total of 527 patients underwent stenting in the iliofemoral veins, and 32 patients (20 men [63%]) with acute thrombosis in iliofemoral venous stents placed in the previous 14 days were treated in our center from January 2015 to December 2018. The mean time from the onset of symptoms to the intervention was 6 days. Successful thrombolysis was achieved in 31 of the 32 patients, and additional stents were implanted in 16 patients. Patency was achieved in all cases. The underlying factors of early stent thrombosis were technical failure of the initial procedure, such as suboptimal positioning, failure owing to stent characteristics (stent kinking, compression, and angulation), in-stent residual thrombus, and inadequate anticoagulation. In all cases, recanalization was achieved through successful thrombolysis with or without restenting.

CONCLUSIONS

Treatment with CDT and stenting of early in-stent thrombosis is effective and feasible. Recanalization of stented segment(s) can be achieved in most cases of recent thrombosis (<14 days). Early stent-related occlusion is mainly caused by stent-related problems and technical inadequacies.

Pediatric Thrombolysis: A Practical Approach

The incidence of pediatric venous thromboembolic disease is increasing in hospitalized children. While the mainstay of treatment of pediatric thrombosis is anticoagulation, reports on the use of systemic thrombolysis, endovascular thrombolysis, and mechanical thrombectomy have steadily been increasing in this population. Thrombolysis is indicated in the setting of life- or limb-threatening thrombosis. Thrombolysis can rapidly improve venous patency thereby quickly ameliorating acute signs and symptoms of thrombosis and may improve long-term outcomes such as postthrombotic syndrome. Systemic and endovascular thrombolysis can result in an increase in minor bleeding in pediatric patients, compared with anticoagulation alone, and major bleeding events are a continued concern. Also, endovascular treatment is invasive and requires technical expertise by interventional radiology or vascular surgery, and such expertise may be lacking at many pediatric centers. The goal of this mini-review is to summarize the current state of knowledge of thrombolysis/thrombectomy techniques, benefits, and challenges in pediatric thrombosis.

Risk factors of postthrombotic syndrome before and after deep venous thrombosis treatment

Postthrombotic syndrome is the most common complication after deep venous thrombosis. Postthrombotic syndrome is a debilitating disease and associated with decreased quality of life and high healthcare costs. Postthrombotic syndrome is a chronic disease, and causative treatment options are limited. Prevention of postthrombotic syndrome is therefore very important. Not all patients develop postthrombotic syndrome. Risk factors have been identified to try to predict the risk of developing postthrombotic syndrome. Age, gender, and recurrent deep venous thrombosis are factors that cannot be changed. Deep venous thrombosis location and extent seem to predict severity of postthrombotic syndrome and are potentially suitable as patient selection criteria. Residual thrombosis and reflux are known to increase the incidence of postthrombotic syndrome, but are of limited use. More recently developed treatment options for deep venous thrombosis, such as new oral factor X inhibitors and catheter-directed thrombolysis, are available at the moment. Catheter-directed thrombolysis shows promising results in reducing the incidence of postthrombotic syndrome after deep venous thrombosis. The role of new oral factor X inhibitors in preventing postthrombotic syndrome is still to be determined.