Catheter-Directed Thrombolysis Protocols for Deep Venous Thrombosis of the Lower Extremities-A Systematic Review and Meta-analysis

OBJECTIVE

 To summarize characteristics, complications, and success rates of different catheter-directed thrombolysis (CDT) protocols for the treatment of lower extremity deep venous thrombosis (LE-DVT).

METHODS

 A systematic review using electronic databases (MEDLINE, Scopus, and Web of Science) was performed to identify randomized controlled trials and observational studies related to LE-DVT treated with CDT. A random-effects model meta-analysis was performed to obtain the pooled proportions of early complications, postthrombotic syndrome (PTS), and venous patency.

RESULTS

 Forty-six studies met the inclusion criteria reporting 49 protocols (n = 3,028 participants). In studies that addressed the thrombus location (n = 37), LE-DVT had iliofemoral involvement in 90 ± 23% of the cases. Only four series described CDT as the sole intervention for LE-DVT, while 47% received additional thrombectomy (manual, surgical, aspiration, or pharmacomechanical), and 89% used stenting.Definition of venogram success was highly variable, being the Venous Registry Index the most used method (n = 19). Among those, the minimal thrombolysis rate (<50% lysed thrombus) was 0 to 53%, partial thrombolysis (50-90% lysis) was 10 to 71%, and complete thrombolysis (90-100%) was 0 to 88%. Pooled outcomes were 8.7% (95% confidence interval [CI]: 6.6-10.7) for minor bleeding, 1.2% (95% CI: 0.8-1.7%) for major bleeding, 1.1% (95% CI: 0.6-1.6) for pulmonary embolism, and 0.6% (95% CI: 0.3-0.9) for death. Pooled incidences of PTS and of venous patency at up to 1 year of follow-up were 17.6% (95% CI: 11.8-23.4) and 77.5% (95% CI: 68.1-86.9), respectively.

CONCLUSION

 Assessment of the evidence is hampered by the heterogeneity of protocols, which may be reflected in the variation of PTS rates. Despite this, CDT is a low-risk treatment for LE-DVT.

Society of Interventional Radiology Position Statement on the Endovascular Management of Acute Iliofemoral Deep Vein Thrombosis

PURPOSE

To establish the updated position of the Society of Interventional Radiology (SIR) on the endovascular management of acute iliofemoral deep vein thrombosis (DVT).

MATERIALS AND METHODS

A multidisciplinary writing group with expertise in treating venous diseases was convened by SIR. A comprehensive literature search was conducted to identify studies on the topic of interest. Recommendations were drafted and graded according to the updated SIR evidence grading system. A modified Delphi technique was used to achieve consensus agreement on the recommendation statements.

RESULTS

A total of 84 studies, including randomized trials, systematic reviews and meta-analyses, prospective single-arm studies, and retrospective studies were identified and included in the review. The expert writing group developed 17 recommendations that pertain to the care of patients with acute iliofemoral DVT with the use of endovascular venous interventions.

CONCLUSIONS

SIR considers endovascular thrombus removal to be an acceptable treatment option in selected patients with acute iliofemoral DVT. Careful individualized risk assessment, high-quality general DVT care, and close monitoring during and after procedures should be provided.

Comparison of Aspiration Thrombectomy to other endovascular therapies for Proximal Upper Extremity Deep Venous Thrombosis

OBJECTIVE

Catheter-directed thrombolysis (CDT) provides an effective method for clearing deep venous thrombosis (DVT). Unfortunately, CDT is associated with hemorrhagic complications. This study evaluated the technical success of the various endovascular therapies including a new mechanical aspiration thrombectomy (AT) device for the treatment of acute upper extremity deep venous thrombosis (UEDVT).

METHODS

This was a single-center retrospective review of patients with acute symptomatic proximal UEDVT secondary to venous thoracic outlet syndrome. Undergoing endovascular therapy from December 2013 to June 2019. Patients were treated with a variety of methods including CDT, ultrasound assisted thrombolysis (USAT), rheolytic thrombectomy (RT) and aspiration thrombectomy (AT). We evaluated outcomes for patients undergoing AT compared to non-aspiration thrombectomy (NAT) techniques. The primary outcome was technical success, defined as resolution of >70% of thrombus. The secondary endpoint was the ability to complete the therapy in a single session.

RESULTS

There were 22 patients who had endovascular management of their symptomatic proximal UEDVT. All 22 (100%) patients were successfully treated with greater than 70% thrombus resolution. 10 patients underwent AT, of which 50% (5/10) had single session therapies. 12 patients underwent NAT (3 had CDT or USAT alone; 3 had USAT with RT; and 6 had CDT followed by RT), with single session therapy occurring in only 8.3% (1/12) of the NAT group. The average total dose of thrombolytics was 12.6mg (SD= 9.65) in the AT group compared to 19.0mg (SD= 5.78) in the NAT group (mean difference -6.4; 95% CI -1.1, 13.9). All but one of the patients in the AT group went on to have successful first rib resections. All NAT patients had successful first rib resections. Venogram was not performed at the time of decompression. All patients except one underwent resection via the infraclavicular approach, with rib removal posterior to the brachial plexus, a median of 8.0 [IQR 6.0, 12.0] days following DVT therapy.

CONCLUSIONS

In this study, technical success of 100% was achieved for acute symptomatic proximal UEDVT therapies. AT technology allows for higher rates of treatment in a single session thereby minimizing a patient's risks of bleeding complications. Further research is needed to further define the role of this new technology in the treatment paradigm of UEDVT management.

Efficacy of ultrasound-accelerated versus traditional catheter-directed thrombolysis in treatment of lower extremity deep venous thrombosis: A protocol for systematic review and meta-analysis

BACKGROUND

There is no meta-analysis or review in the literature to compare and evaluate the difference and effectiveness of ultrasonic-accelerated thrombolysis (UAT) and catheter directed thrombolysis (CDT) in lower extremity deep vein thrombosis (DVT) patients. Therefore, we conducted this protocol of systematic review and meta-analysis to evaluate the efficacy between UAT and CDT for patients with lower extremity DVT.

METHODS

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols reporting guidelines to conduct this study. Reviewers will search the PubMed, Cochrane Library, Web of Science, and EMBASE online databases using the key phrases "deep venous thrombosis," "thrombolysis," and "ultrasound-accelerated" for all cohort studies published up to July 22, 2021. There is no restriction in the dates of publication or language in the search for the current review. The primary outcome is major bleeding. Secondary outcomes include health-related quality of life and complications such as recurrent venous thromboembolism, pulmonary embolism, in-stent thrombosis, and death. Review Manager software (v 5.4; Cochrane Collaboration) will be used for the meta-analysis. A P value of < .05 is considered to be statistically significant.

RESULTS

We hypothesized that these two methods would provide similar therapeutic benefits.

OSF REGISTRATION NUMBER

10.17605/OSF.IO/YZB3H.

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.

Endovascular management of the deep venous thrombosis: A new challenging role for the endovascular specialist in 2020

Over the last years, the endovascular approach to the management of the acute and chronic deep vein thrombosis (DVT) has gained more and more attention from the scientific community. DVT is the third most common cardiovascular disease after coronary heart disease and stroke, with classic treatment based on anticoagulation. Recent evidences have highlighted the risk of postthrombotic syndrome as high as 30%-50% in proximal ilio-femoral lesions, with irreversible clinical symptoms and impact on the quality of life of the population. Since 2000s, the new concept of thrombus removal in the acute phase has been supported by the introduction of different techniques based on the endovascular ablation of the clot by in-situ fibrinolysis and, more recently, fragmentation and aspiration. In the chronic phase, recanalization of the thrombosed segment is recommended by stent placement to remove the obstruction and eventually reduce the congestion. Immediate technical success of these procedures is widely satisfying, whereas the long-term clinical benefits are still debated. This paper presents an overview of the modern management of the DVT by endovascular approach with regard to the clinical contexts, interventional strategies and clinical outcomes. Endovascular specialist needs to be aware of this incoming challenge, as local expertise is demanded for the modern management of these patients in multidisciplinary theaters.

Catheter-Directed Thrombectomy for Highly Symptomatic Patients with Iliofemoral Deep Venous Thrombosis not Responsive to Conservative Treatment

PURPOSE

The use of pharmacomechanical thrombectomy in patients with symptomatic iliofemoral deep venous thrombosis (DVT) not responsive to conservative treatment is under-investigated until now. This prompted us to review and analyze our results (technical/clinical outcome, complications) and compare them to the current literature.

MATERIALS AND METHODS

Between 2013 and 2019, 19 patients (14 women and 5 men; mean age: 41.2 years, SD: 18.2) with iliofemoral DVT and excessive pain not responsive to conservative treatment were treated with pharmacomechanical thrombectomy. Patients were followed up for 12 months. Demographics, technical success and clinical outcome data (pain score/Villalta score) were collected.

RESULTS

Thrombectomy ± thrombolysis was successful in all cases (n = 19). No major complications were observed. Eight out of nineteen cases developed hematoma at the sheath insertion site not requiring further treatment. Seven out of nineteen cases required additional continuous lysis for complete iliofemoral clot solution. All patients received balloon angioplasty to treat post-thrombotic strictures. In 16/19 cases, stents were placed to preserve iliofemoral caliber and maintain unrestricted iliac venous outflow. Three patients (16%) required re-intervention due to re-thrombosis or in-stent stenosis after 4, 14 days and 4 months, respectively. Symptoms could be improved temporarily or indefinitely in 19 out of 19 patients. 1 year following thrombectomy mean pain score was reduced by 87%, mean Villalta score was 2.6 (SD: 4), and iliofemoral veins were patent in 15/17 patients.

CONCLUSION

In symptomatic patients with iliofemoral DVT, refractory to conservative treatment, catheter-directed thrombectomy enables rapid and long-lasting pain relief. High patency rates can be achieved in patients receiving PTA and venous stenting post-thrombectomy.

Ultrasound improves the outcomes of cardiopulmonary resuscitation in rats by stimulating the cholinergic anti‑inflammatory pathway

The present study investigated the effects of the ultrasound (US), a noninvasive technique, on ischemia-reperfusion injury (IRI) following cardiopulmonary resuscitation (CPR). The animals used in the present study were randomized into five groups (n=8 per group) as follows: i) The CPR group, where the rats underwent 6 min of untreated ventricular fibrillation (VF) followed by CPR and defibrillation; ii) the US group, in which the treatment was identical to the CPR group with the exception that rats were exposed to US treatment 24 h prior to CPR; iii) the MLA group, in which the treatment was identical to the US group with the exception that the α7 nicotinic acetylcholine receptor (α7nAChR) antagonist MLA (4 mg/kg) was administered 30 min prior to US and VF respectively; iv) the GTS group, in which the treatment was identical to the CPR group with the exception that the α7nAChR agonist GTS-21 (4 mg/kg) was injected 30 min prior to VF; and v) the SHAM group, in which the rats were exposed to surgical preparation without CPR and US application. At 1 day prior to CPR, the US treatment was administered to the left kidney by US pulses (contrast general mode with 9 MHz) with a bursting mechanical index of 0.72 for 2 min. Following treatment of the left kidney, the right kidney was exposed to identical US treatment for an additional 2 min. The results demonstrated that US preconditioning decreased the number of defibrillations required and shortened the duration of CPR. US also suppressed tumor necrosis factor-α and interleukin-6 levels following resuscitation (P<0.05), and a significantly longer overall survival time was observed in the US-treated animals (P<0.01). In addition, US attenuated neuronal injury and promoted the expression of α7nAChR in hippocampal neurons (P<0.05). However, the protective effects of US were abolished by MLA and imitated by GTS-21. The results of the present study demonstrated that prior exposure to US may improve animal outcomes following CPR, and the protective effects of US may be dependent on the cholinergic anti-inflammatory pathway (CAP) via α7nAChR.