Catheter-directed thrombolysis for extensive iliofemoral deep vein thrombosis: review of literature and ongoing trials

Effects of CDT on Hemodynamics and Quality of Life in a Subgroup of Patients with Lower Limb Deep Vein Thrombosis Carel: A Case-Control Study

Objective. To explore the effects of combined catheter-directed thrombolysis (CDT) on hemodynamics and quality of life in a subgroup of patients with lower limb deep vein thrombosis carel by using a case-control study. Methods. Eighty-four patients with deep venous thrombosis (DVT: acute DVT and chronic DVT) of lower extremities treated in our hospital from April 2017 to June 2021 were randomly assigned into the control group ( $n=42$ ) and the research group ( $n=42$ ). The control group only received routine nursing combined with CDT; the research group was treated with cluster nursing l combined with CDT. The clinical efficacy, the difference in limb circumference, hemorheology, hemodynamics, coagulation index and life quality before and after treatment, and the nursing satisfaction scores were calculated. The effects of cluster nursing l combined with CDT on hemodynamics and life quality in patients with DVT of lower extremities were analyzed. Results. The clinical curative effect of the research group was better than that of the control group ( $P<0.05$ ). After intervention, the difference in the thigh and leg perimeter in the research group was reduced, and the difference in the thigh and leg perimeter in the research group was significantly lower than that in the control group ( $P<0.05$ ). After intervention, the whole blood low shear viscosity, plasma viscosity, platelet aggregation rate, and fibrinogen in the research group were lower than those in the control group ( $P<0.05$ ). After intervention, segmental venous volume (SVC), maximum venous blood flow (MVO), and SVC/MVO in the research group were significantly higher than those before intervention, VRT was significantly prolonged, and MVO and venous pressure recovery time (VRT) were significantly higher than those in the control group. After intervention, D-dimer and fibrinogen decreased, prothrombin time and activated partial thromboplastin time increased in the research group, and the improvement of blood coagulation index in the research group was significantly better than that in the control group ( $P<0.05$ ). After intervention, the scores of quality of life in the research group decreased, and the scores of physiological function, psychological function, social function, and health self-cognition in the research group were lower than those in the control group ( $P<0.05$ ). The satisfaction of patients in the research group was significantly higher than that in the control group ( $P<0.05$ ). Conclusion. The application of cluster nursing l combined with CDT can effectively prevent lower limb venous thrombosis after operation and can enhance patients’ hemorheology, hemodynamics, and blood coagulation function and significantly promote their life quality, nursing satisfaction is high, and it is worth popularizing and applying in clinic.

Ten-year trends in iliofemoral deep vein thrombosis treatment and referral pathways

OBJECTIVES

Iliofemoral deep venous thrombosis is associated with an increased risk of developing post-thrombotic syndrome resulting in reduced quality of life. As there is debate about best management practices, this study aimed to examine the referral and treatment pathways for patients presenting with iliofemoral deep venous thrombosis over an 11-year period at our institution.

METHODS

We conducted a retrospective review of patients diagnosed with lower limb deep vein thrombosis between 2010 and 2020. Ultrasound report findings were reviewed for the presence of iliofemoral deep venous thrombosis with acute, occlusive, or proximal clot. Multiple factors were extracted, including patient demographics, risk factors, diagnostic methods, interventions, referrals, and details of follow-up. The CaVenT and ATTRACT trials studied the benefit of thrombolysis in the early phase of iliofemoral deep venous thrombosis management as compared to anticoagulation alone. An analysis was conducted of patients requiring thrombolysis to determine whether these trials impacted physician practice patterns for thrombolysis. Data were organized and examined by year for trends in treatment and referral pathways.

RESULTS

The review yielded 2792 patients assessed for lower limb deep venous thrombosis by ultrasound. Four hundred and sixty-seven (16.7%) patients were confirmed to have an occlusive iliofemoral deep venous thrombosis. The average age was 62.7 years (18-101 years). Half (50.4%) of the patients were male. The most common etiology for clot was malignancy-induced hypercoagulable state (39.0%). There was no difference in incidence of iliofemoral deep venous thrombosis diagnosed by ultrasound per year, with an average of 42.5 per year and a peak of 61. There was a trend towards increased rates of computed tomography imaging, ranging between 9.1% and 52.9%. The rate thrombolysis per year ranged between 1.8% and 8.9%, with a range of 4.3% (n = 20) to 8.9% (n = 5) in 2018. The use of pharmacomechanical thrombolysis increased, from 25% (n = 1) in 2010-2012 to 87.5% (n = 7) in 2018-2020. The rate of inferior vena cava filter insertion alone decreased from 18.2% in 2010 (n = 4) to 5.9% (n = 1) in 2020. The length of thrombolysis treatment also decreased, from 100% of patients (n = 4) receiving treatment duration greater than 24 h in 2010-2012 to 0% (n = 0) in 2018-2020. About 45% of patients receiving thrombolysis (n = 9) had venous stenting. No difference in treatment outcomes were observed, with greater than 87.5% of patients reaching intermediate to full resolution of clot burden. No patients experienced intracranial hemorrhage.

CONCLUSIONS

The results of this analysis highlight the change in practice in our institution over time. The low rate of intervention likely reflects the current lack of consensus in published guidelines. It is important for future work to elicit the most appropriate management pathways for patients with iliofemoral deep venous thrombosis.

Safety and efficacy of pharmacomechanical thrombolysis for acute and subacute deep vein thrombosis patients with relative contraindications

To evaluate the safety and efficacy of pharmacomechanical thrombolysis (PMT) performed for patients with relative contraindications.From June 2014 to December 2016, 112 patients with acute or subacute proximal deep vein thrombosis (DVT) were enrolled in this study. 60 patients (including 27 acute DVT patients and 33 subacute DVT patients) were treated with catheter-directed thrombolysis (CDT), and 52 patients with relative contraindications (including 25 acute DVT patients and 27 subacute DVT patients) with PMT. Assessment of venous recanalization was conducted using venography the time Inferior vena cava filter is removed, and complications were used to compare safety and efficacy between the groups.The outcomes of acute DVT patients no matter which kind of therapy performed, CDT or PMT, were significant better than subacute DVT patients (PCDT = .04 and PPMT = .01). However, there was no significant difference between CDT acute group and PMT acute group or between CDT subacute group and PMT subacute group (Pacute = .80 and Psubacute = .84). For complications of all patients, there was no mortality and major bleeding occurred.PMT could be a safe and effective management for DVT patients with relative contraindications, and the acute DVT may achieve better outcomes when they receive CDT or PMT.

Administration routes affect thrombolytic effect of catheter-directed thrombolysis with pro-urokinase in treating deep vein thrombosis

Background

Deep venous thrombosis (DVT) is a common disorder with a significant mortality rate. Catheter-directed thrombolysis (CDT) is a preferred treatment for DVT patients. The aim of this study is to evaluate the thrombolytic effect of CDT with pro-urokinase (pro-UK) in different administration routes.

Methods

An inferior vena cava (IVC) model was induced in 36 New Zealand white rabbits by catheter injury and placement of IVC filter. The animals were divided into 6 groups with 6 rabbits in each group: group A: systemic thrombolysis with intravenous injection; group B: CDT with pump infusion; group C: CDT with pulse injection; group D: CDT with combination of pump infusion and pulse injection; group E: catheter-directed aspiration thrombectomy; group F: mechanical thrombectomy. The thrombolytic effects were evaluated by color Doppler ultrasound and blood measurement of D-dimer and fibrinogen.

Results

The minimum effective concentration of pro-UK solution was identified. Two groups (group A and B) did not achieve successful thrombolysis. Among all catheter-directed administration groups, the rabbit groups that received pro-UK therapy through catheter-directed thrombolytic pump infusion combined with pulse injection (group D) showed the best thrombolysis effect. In contrast, catheter-directed aspiration thrombectomy (group E) is effective but not safe.

Conclusions

CDT with combination of pump infusion and pulse injection of pro-UK safely and significantly improves thrombolysis procedure in rabbits, suggesting potential benefits from the use of CDT in proximal DVT.

Recurrent Iliofemoral Venous Thrombosis in the Setting of May-Thurner Syndrome as the Presenting Symptom of Behcet's Disease

BACKGROUND

Vascular manifestations including pulmonary artery aneurysms and venous thrombosis are seen in up to 14% of patients with Behcet's disease. We report a patient who had recurrent deep vein thrombosis (DVT) as the presenting symptom of Behcet's Disease.

METHODS

A 19-year-old male who presented with acute iliofemoral DVT, confirmed by intravascular ultrasound (IVUS) and venogram. May-Thurner syndrome was also observed. Repeated catheter-based pharmacomechanical thrombolysis, thrombectomy, and subsequent iliac vein stenting were performed. The patient was then discharged on rivaroxaban and aspirin.

RESULTS

Five months later, the patient experienced left calf pain. In the interim, he had been diagnosed with Behcet's disease by a rheumatologist who was consulted due to oral ulcers and skin lesions and accordingly started on prednisone, colchicine, and azathioprine. At this time, IVUS and venogram revealed thrombotic occlusion of the previously placed stent. Tissue plasminogen activator was infused into the stent, and pharmacomechanical thrombectomy restored flow through the left iliac veins. Follow-up laboratory workup revealed that subtherapeutic azathioprine dosing, and after appropriate adjustment, the patient has been asymptomatic for 12 months.

CONCLUSIONS

Acute refractory DVT is a possible presenting symptom of Behcet's disease, which may be complicated by May-Thurner syndrome. Such patients should receive therapeutic immunosuppression in addition to anticoagulation.

Catheter-Directed Thrombolysis Versus Standard Anticoagulation for Acute Lower Extremity Deep Vein Thrombosis: A Meta-Analysis of Clinical Trials

Standard anticoagulant treatment alone for acute lower extremity deep vein thrombosis (DVT) is ineffective in eliminating thrombus from the deep venous system, with many patients developing postthrombotic syndrome (PTS). Because catheter-directed thrombolysis (CDT) can dissolve the clot, reducing the development of PTS in iliofemoral or femoropopliteal DVT. This meta-analysis compares CDT plus anticoagulation versus standard anticoagulation for acute iliofemoral or femoropopliteal DVT. Ten trials were included in the meta-analysis. Compared with anticoagulant alone, CDT was shown to significantly increase the percentage patency of the iliofemoral vein (P < .00001; I² = 44%) and reduce the risk of PTS (P = .0002; I² = 79%). In subgroup analysis of randomized controlled trials, CDT was not shown to prevent PTS (P = .2; I² = 59%). A reduced PTS risk was shown, however, in nonrandomized trials (P < .00001; I² = 47%). Meta-analysis showed that CDT can reduce severe PTS risk (P = .002; I² = 0%). However, CDT was not indicated to prevent mild PTS (P = .91; I² = 79%). A significant increase in bleeding events (P < .00001; I² = 33%) and pulmonary embolism (PE) (P < .00001; I² = 14%) were also demonstrated. However, for the CDT group, the duration of stay in the hospital was significantly prolonged compared to the anticoagulant group (P < .00001; I² = 0%). There was no significant difference in death (P = .09; I² = 0%) or recurrent venous thromboembolism events (P = .52; I² = 58%). This meta-analysis showed that CDT may improve patency of the iliofemoral vein or severe PTS compared with anticoagulation therapy alone, but measuring PTS risk remains controversial. However, CDT could increase the risk of bleeding events, PE events, and duration of hospital stay.

Venous function after pharmacomechanical thrombolysis for extensive iliofemoral deep vein thrombosis

Background: Chronic venous insufficiency is an important complication following iliofemoral deep venous thrombosis. Early thrombus removal may preserve venous function and prevent this complication. This study represents the largest reported South African series of pharmacomechanical thrombolysis for iliofemoral deep venous thrombosis to date.Objective: To evaluate the long-term outcome following pharmacomechanical thrombolysis for proximal and extensive deep venous thrombosis in a private, specialist vascular unit.Methods: All patients who underwent pharmacomechanical thrombolysis for iliofemoral deep venous thrombosis between August 2009 and January 2016 were invited to return for clinical assessment and venous ultrasound. Clinical findings were recorded according to the Villalta score and clinical, etiology, anatomic and pathology (CEAP) classification. The quality of life (QoL) was assessed utilising the VEINES-QoL/Sym questionnaire, providing two scores per patient, one describing the QoL and the other symptom severity (Sym).Results: Thirty two patients (35 legs) were evaluated. There were 25 females and 7 males, with a mean age of 33.5 years (±14 years). The mean follow-up period was 31 months (range 3 months – 80 months). Results of the CEAP classification were C0 = 24 (75%), C1 = 1 (4%), C2 = 2 (6%), C3 = 2 (6%) and C4 = 3 (9%). Thirty-one (97%) patients had Villalta scores from 0 to 4, indicating no or mild evidence of venous disease. One patient (3%) had a Villalta score of 6, indicating post-thrombotic syndrome. The mean QoL score was 87% (±12) and the mean Sym score was 86% (±14). Twenty-four (75%) patients had no abnormality on ultrasound, with fibrosis the most observed abnormality.Conclusion: Most patients who had undergone pharmacomechanical thrombolysis for extensive iliofemoral deep venous thrombosis showed few significant clinical signs of chronic venous insufficiency, had excellent function on venous ultrasound and reported excellent QoL.

Guided longer pulses from a diagnostic ultrasound and intraclot microbubble enhanced catheter-directed thrombolysis in vivo

The mechanism of ultrasound thrombolysis (UT) is generally attributed to cavitation. The insufficiency of microbubbles (MB) to serve as cavitation nuclei in the vessel-obstructing thrombi significantly reduces the effectiveness of UT. Taking advantage of the widely performed catheter-directed therapy (CDT), in a thrombo-embolized rabbit IVC model with a simultaneous catheter directed rt-PA thrombolysis procedure, guided moderate mechanical index longer pulses from a modified diagnostic ultrasound transducer, combined with an intraclot infusion of MB, significantly accelerated the thrombolysis process. The higher thrombolysis efficacy score and consistent elevated post-treatment plasma concentration level of D-Dimer, a product of fibrinolysis, both indicated the superiority of CDT + UT over CDT/UT alone. Pathologic examination of the treated occluded IVC segments revealed an almost complete dissolution of the thrombi treated with CDT + UT. There was no evidences of thrombo-embolism or local thrombus formation in the cardiac-pulmonary vessels. Combined with intraclot infusion of MB, guided longer pulse ultrasound from a diagnostic transducer is able to safely and significantly improve a catheter-directed thrombolysis procedure. It thus has the potential to achieve earlier clot removal, administration of a lower dosage of thrombolytic agent and, consequently, a lower incidence of thrombolysis-related side effects.

An Extensive Unprovoked Left Lower Extremity Deep Vein Thrombosis Secondary to an Anatomical Anomaly: A Case of May-Thurner Syndrome

May-Thurner syndrome (MTS) also known as Cockett’s syndrome is a rare condition responsible for 2%-3% of all cases of deep venous thrombosis (DVT). The thrombosis results from mechanical compression of the left common iliac vein against the body of the fifth lumbar vertebra by the right common iliac artery. Repetitive hyperplasia of the venous wall by compression results in spur formation that in turn causes venous flow obstruction and results in the DVT. Our case is a young female who had acute extensive proximal DVT due to MTS that was successfully managed using mechanical thrombectomy with a venous stent. MTS although a rare entity should be suspected especially in young patients with unilateral DVT with extensive clots especially on left lower extremity without any antecedent risk factors.

Patency rate and quality of life after ultrasound-accelerated catheter-directed thrombolysis for deep vein thrombosis

Purpose

Studies on ultrasound-accelerated, catheter-directed thrombolysis of acute deep vein thrombosis emphasize good patency rates and low complication rates. Therefore, we analyzed quality of life besides technical success and patency in our patients after ultrasound-accelerated, catheter-directed thrombolysis.

Methods

Between 2009 and 2014, 42 patients suffering from iliofemoral deep vein thrombosis received ultrasound-accelerated, catheter-directed thrombolysis. Follow-up included clinical exanimation and ultrasound. Thirty patients (36 interventions), mean age 41.3 years (range 19–71 years), 56.6% women (17/30), completed the surveys. Five different scores were used to assess the quality of life and symptoms of postthrombotic syndrome: SF36, Euro-QOL 5D, PDI, VEINES-QOL/Sym, and the Villalta score.

Results

Mean therapy duration of ultrasound-accelerated, catheter-directed thrombolysis was 76.4 h and therapeutic success could be reported in 80.5% (29/36). Successful ultrasound-accelerated, catheter-directed thrombolysis was followed by stent angioplasty in 58.3% (21/36) procedures. Overall complication rate was 19.44%, mainly formed by minor bleedings. Mean follow-up was 38.5 months. The primary patency rate was 63.8%, the assisted-primary and the secondary patency rate were 80.5%. We observed an improved quality of life in our patients’ cohort compared to patients suffering from postthrombotic syndrome.

Conclusion

Although ultrasound-accelerated, catheter-directed thrombolysis is feasible with good patency rates, further prospective randomized trials are necessary to evaluate the value of thrombus removal in iliofemoral deep vein thrombosis in comparison to conservative treatment.