Efficacy, safety, and influencing factors of AngioJet mechanical thrombectomy versus catheter-directed thrombolysis in the treatment of acute lower limb deep vein thrombosis

Abstract

Objective

This study compared the efficacy and safety of AngioJet mechanical thrombectomy and catheter-directed thrombolysis (CDT) in acute lower limb deep vein thrombosis (DVT), while also assessing predictors of thrombus clearance, patient experience, and economic impact.

Methods

A retrospective single-center study included 76 patients with acute lower limb DVT treated between January 2017 and January 2022. Patients received either AngioJet (n = 34) or CDT (n = 42). Clinical data included demographics, thrombus characteristics, thrombolysis duration, urokinase dosage, hospital stay, complications, 12-month Villalta scores and satisfaction ratings. Statistical comparisons used chi-square and t-tests; logistic regression identified predictors of grade III thrombus clearance.

Results

AngioJet achieved a significantly higher grade III clearance rate than CDT (70.6% vs. 45.2%, P < 0.05), with shorter thrombolysis duration, lower urokinase use, and reduced hospital stay (all P < 0.05). Puncture site bleeding rates were similar, but hemoglobinuria occurred more frequently with AngioJet (P < 0.01) and resolved after symptomatic care. At 12 months, Villalta scores were comparable, though slightly lower in the AngioJet group, suggesting potential post-thrombotic syndrome prevention. Independent predictors of grade III clearance were AngioJet treatment and symptom onset ≤ 7 days. AngioJet patients reported greater satisfaction with shorter stays and improved recovery.

Conclusion

AngioJet mechanical thrombectomy offers superior thrombus clearance, shorter treatment times, and better patient-reported outcomes compared with CDT in acute lower limb DVT. Benefits are greatest in early-stage disease or heavy thrombus burden, supporting its broader clinical application.

Introduction

Lower limb deep vein thrombosis (DVT) is a common vascular condition that, in severe cases, can lead to life-threatening pulmonary embolism (PE) and the persistent, debilitating complication known as post-thrombotic syndrome (PTS), significantly affecting patients’ quality of life and long-term outcomes. According to the literature, approximately 30% of patients with DVT develop PTS after treatment, with some experiencing chronic pain, swelling, and skin ulcers [1]. Traditional treatment for DVT primarily relies on anticoagulant therapy, which can inhibit thrombus progression but has limited efficacy in removing existing thrombi, making it difficult to effectively prevent the development of PTS [2].

In recent years, endovascular interventions have become an important adjunct for early thrombus removal in DVT management. Among them, catheter-directed thrombolysis (CDT) enhances thrombolytic efficiency by locally infusing fibrinolytic agents directly into the thrombus. However, CDT requires prolonged infusion, involves high doses of thrombolytic drugs, and carries a certain risk of bleeding. AngioJet mechanical thrombectomy, a pharmacomechanical technique that combines negative pressure aspiration with high-pressure saline jet injection, can rapidly reduce thrombus burden within a short time, while minimizing drug usage and shortening hospital stays. Clinical studies have shown that AngioJet achieves lower PTS incidence and favorable venous recanalization outcomes in patients with acute iliofemoral DVT [3].

Although both of these techniques have been widely used, their efficacy, safety, and impact on mid-term outcomes remain subjects of debate, particularly with regard to the incidence of PTS and patient treatment experience, where research is still relatively limited. Therefore, this study retrospectively analyzed the treatment data of patients with acute lower limb DVT at our center to compare AngioJet and CDT in terms of perioperative efficacy, postoperative complications, short- to mid-term PTS incidence and patient satisfaction. Furthermore, we aimed to identify independent factors associated with thrombus clearance efficacy, in order to provide a reference for optimizing clinical treatment strategies.

Materials

General information

This was a single-center retrospective-controlled study that included a total of 76 patients with acute lower limb deep vein thrombosis (DVT) who were hospitalized in the Department of Vascular Surgery at San-Ming Second Hospital between January 2017 and January 2022.

Inclusion criteria were: Symptom onset within ≤ 14 days; DVT confirmed by color Doppler ultrasound or digital subtraction angiography (DSA); Clinical presentation consists of swelling and pain in the affected limb, with or without superficial varicose veins.

Exclusion criteria included: Severe cardiac, cerebral, pulmonary, hepatic, or renal insufficiency; Active bleeding or contraindications to thrombolytic therapy; Presence of right-to-left intracardiac shunt, tumor thrombus, or expected survival < 1 year; Inability to comply with follow-up after surgery.

Patients were divided into the AngioJet group (n = 34) and the CDT group (n = 42) based on the actual treatment received. There were no statistically significant differences between the two groups in terms of sex, age, symptom onset time, or thrombus distribution, indicating comparability.

Treatment methods

AngioJet Group

Following puncture of the contralateral femoral vein and placement of an inferior vena cava (IVC) filter, a sheath was inserted via the ipsilateral popliteal vein. After angiographic confirmation of the thrombus, a 6 F AngioJet catheter was used to perform mechanical thrombectomy combined with local infusion of urokinase (250,000 U). Post-procedural angiography was conducted to assess thrombus clearance, and the decision to place an iliac vein stent during the same session was made accordingly. Postoperatively, patients received anticoagulation therapy along with supportive measures including diuresis, hydration, and urine alkalization.

CDT Group

The access route was the same. After placement of an appropriately sized thrombolytic catheter, continuous infusion of urokinase (250,000 U every 12 h) was administered for 3–5 days. Treatment efficacy was evaluated based on clinical improvement and laboratory markers such as D-dimer and fibrinogen (FIB). Post-treatment angiography was used to determine the need for stent placement and IVC filter retrieval (Fig. 1).

Fig. 1.

Pre-and post-procedural venography with AngioJet. (A) Preoperative venography of the iliac vein and common femoral vein; (B) Postoperative venography of the iliac vein and common femoral vein; (C) Preoperative venography of the superficial femoral vein and popliteal vein; (D) Postoperative venography of the superficial femoral vein and popliteal vein. (Black arrow indicates common femoral vein; white arrow indicates superficial femoral vein)

In general, the thrombolytic activity was standardized using urokinase, with 250,000 U locally administered during AngioJet thrombectomy or 250,000 U infused every 12 h for 3–5 days in CDT, ensuring comparable total enzymatic exposure across groups. The AngioJet system provided a short-term, high-intensity pharmacomechanical thrombolytic effect, while CDT maintained a prolonged, low-intensity thrombolysis through continuous infusion.

Postoperative follow-up and outcome measures

All patients received standardized anticoagulation therapy postoperatively, using novel oral anticoagulants such as rivaroxaban for a duration of 12–24 months. After discharge, patients were advised to wear Class II medical compression stockings for 6–24 months, with the duration tailored individually based on the extent of thrombosis, symptom resolution, and patient compliance. Follow-ups were conducted at 3, 6, 9, and 12 months postoperatively through outpatient visits or telephone interviews, achieving a 100% follow-up rate.

Multiple clinical efficacy and prognostic indicators were evaluated during follow-up. Thrombus clearance was assessed intraoperatively via digital subtraction angiography (DSA) and categorized by percentage as:

• Grade I (< 50%),

• Grade II (50%–95%),

• Grade III (> 95%),

with Grade III considered complete or near-complete thrombus clearance.

Perioperative efficacy indicators included:

• Thrombolysis duration (total intraoperative and postoperative duration of thrombolytic drug use, measured in days),

• Total urokinase dosage (in 10,000-unit increments),

• Length of hospital stay (from admission or ward transfer to discharge),

• Placement of iliac vein stent (based on angiographic evidence of > 50% vascular stenosis).

Postoperative complications were recorded, including:

• Puncture site bleeding (requiring local compression),

• Hemoglobinuria (presence of tea-colored urine, assessed in conjunction with hemolysis and renal function monitoring), among other adverse clinical events.

At 12 months, the occurrence of post-thrombotic syndrome (PTS) was evaluated using the Villalta score, which includes 9 criteria such as limb swelling, pain, heaviness, skin pigmentation, induration, and varicose veins. Each item is scored 0–3 points. A total score ≥ 5 indicates PTS, and a score ≥ 15 or the presence of chronic venous ulcers defines severe PTS.

In addition, patient satisfaction was assessed using a five-point Likert scale, covering subjective impressions of treatment efficacy, symptom relief, doctor–patient communication, and overall hospitalization experience.

Statistical methods

Data were analyzed using SPSS 26.0 statistical software. Continuous variables were expressed as mean ± standard deviation (x̄ ± s), and comparisons between groups were performed using independent sample t-tests. Categorical variables were analyzed using the chi-square test or Fisher’s exact test, while ordinal data were analyzed using the rank-sum test.

Grade III thrombus clearance was used as the dependent variable. After univariate analysis of factors such as treatment modality, symptom onset time, and thrombus extent, variables were entered into a multivariate logistic regression model to identify independent predictors. A p-value < 0.05 was considered statistically significant.

Results

Comparison of clinical characteristics, perioperative efficacy, and complications

There were no statistically significant differences between the two groups in terms of sex, age, symptom onset time, or thrombus distribution (P > 0.05), indicating comparability (Table 1). The rate of Grade III thrombus clearance was 70.6% (24/34) in the AngioJet group and 45.2% (23/42) in the CDT group, with the difference being statistically significant (P < 0.05). The AngioJet group had significantly shorter thrombolysis time (11.85 ± 5.77 h), lower urokinase dosage (307,100 ± 161,600 U), and shorter hospital stay (3.91 ± 0.97 days) compared to the CDT group (74.71 ± 29.94 h, 1,791,400 ± 710,600 U, and 12.05 ± 3.83 days, respectively), all differences statistically significant (P < 0.05).

Table 1.

Baseline characteristics of patients

Variable	AngioJet Group	CDT Group	t/χ²	P Value
Sex			0.030	0.863
- Male	13	18
- Female	21	24
Age (x̄ ± s, years)	53.47 ± 12.45	51.93 ± 15.03	0.480	0.633
Time from onset (x̄ ± s, days)	8.00 ± 3.80	6.95 ± 3.65	1.220	0.226
Affected Limb			0.008	0.929
- Left	27	33
- Right	7	9
Thrombosis Location			0.197	0.657
- Iliofemoral type	13	14
- Whole limb type	21	28

Regarding complications, the incidence of puncture site bleeding was 2.9% (1/34) in the AngioJet group versus 16.7% (7/42) in the CDT group, showing a statistically significant difference (P < 0.05). The incidence of hemoglobinuria was 11.7% (4/34) in the AngioJet group and 11.9% (5/42) in the CDT group, with no statistically significant difference (P > 0.01) (Table 2). All cases resolved with hydration and diuretic therapy, with no cases of significant renal impairment observed.

Table 2.

Comparison of perioperative treatment between groups

	AngioJet Group	CDT Group	t/χ²	P Value
Thrombus Clearance Rate			6.214	0.045
I	2	9
II	8	14
III	24	19
Thrombolysis Time (x̄ ± s, d)	11.85 ± 5.77	74.71 ± 29.94	12.050	0.001
Urokinase Dosage (x̄ ± s, 10,000 U)	30.71 ± 16.16	179.14 ± 71.06	11.920	0.001
Hospital Stay (x̄ ± s, d)	3.91 ± 0.97	12.05 ± 3.83	12.081	0.001
Complications			4.479	0.034
Puncture Site Bleeding	1	7
Hemoglobinuria	4	5

Postoperative follow-up results

All patients completed 12-month postoperative follow-up. The mean Villalta score was 5.00 ± 3.73 in the AngioJet group and 7.83 ± 4.78 in the CDT group, with the difference being statistically significant (t = 2.824, P = 0.003). The incidence of PTS was 41.2% (14/34) in the AngioJet group and 74.8% (31/42) in the CDT group, a statistically significant difference (χ² = 8.285, P = 0.004), indicating better mid-term PTS control in the AngioJet group, showing an improving trend (Fig. 2, Kaplan–Meier curve).

Fig. 2.

Kaplan–Meier curve

Potential factors affecting PTS occurrence

Using PTS occurrence as the dependent variable, univariate analysis was performed including variables such as sex, age, symptom onset time, affected site, and treatment modality. Results showed significant correlations of PTS with treatment method (AngioJet), hospital stay, urokinase dosage, and thrombolysis duration (P < 0.05) (Table 3). However, further multivariate logistic regression analysis revealed no independent factors significantly influencing PTS occurrence.

Table 3.

Results of univariate analysis

Variable	Test Statistic (Mann-Whitney U/χ²)	P-value
Treatment Modality	6.989	0.008
Age	635.5	0.515
Sex	0.296	0.587
Hospital Stay Duration	969.5	0.004
Affected Limb	0.001	0.988
Lesion Site	0.545	0.461
Urokinase Dosage	948	0.004
Thrombolysis Duration	961.5	0.005

Patient treatment satisfaction

The average patient satisfaction score was 4.0 ± 0.8 in the AngioJet group and 3.8 ± 0.7 in the CDT group. Although this difference was not statistically significant (P > 0.05), the overall scores suggest a better treatment experience with AngioJet. (Fig. 3, including bar charts comparing satisfaction scores). The shorter hospital stay and more concentrated intervention contributed to higher overall patient acceptance.

Fig. 3.

Bar charts comparing satisfaction scores

Discussion

This study compared the clinical efficacy, safety, and mid- to short-term prognosis of AngioJet mechanical thrombectomy versus catheter-directed thrombolysis (CDT) in the treatment of acute lower limb deep vein thrombosis (DVT), and further explored factors influencing thrombus clearance. The results demonstrated that AngioJet outperformed CDT in thrombus clearance rate, thrombolysis duration, hospital stay, and patient satisfaction. Additionally, the incidence of post-thrombotic syndrome (PTS) showed a downward trend in the AngioJet group, suggesting its higher clinical value in certain acute DVT patients.

The AngioJet group achieved a higher rate of Grade III thrombus clearance and shorter thrombolysis time, consistent with findings by Braunschweig et al., who reported a 92% venous recanalization rate and significantly lower PTS incidence in iliofemoral DVT patients treated with AngioJet compared to CDT [3]. Lin et al. also noted that the AngioJet system allows rapid and effective thrombus debulking, significantly reducing urokinase dosage and thrombolysis time [4], which helps lower drug-related bleeding risks.

Regarding PTS incidence, although the difference between groups at 12 months was not statistically significant in our study, the AngioJet group had slightly lower Villalta scores, showing an improving trend. Vedantham et al. in the ATTRACT trial indicated that aggressive thrombus removal in proximal DVT patients can partially reduce moderate-to-severe PTS risk [5]. The PEARL trial by Razavi et al. further demonstrated that AngioJet treatment effectively lowers PTS scores with comparable recanalization rates to CDT [6]. A recent meta-analysis also confirmed that AngioJet combined therapy significantly reduces PTS incidence compared to CDT alone (OR 0.58, 95% CI 0.37–0.91, P = 0.02) [7].

In terms of safety, the incidence of puncture site bleeding was similar between groups, while postoperative hemoglobinuria was more common in the AngioJet group, likely due to red blood cell destruction caused by high-speed saline jet impingement [8]. However, most patients experienced symptom relief after hydration, alkalization, and diuretic treatment, with no significant renal impairment observed, consistent with Kaymaz et al.’s findings [9]. Moreover, the substantially reduced thrombolytic drug dose in AngioJet therapy is expected to lower systemic bleeding risk, which has been supported by multiple clinical practice studies [10, 11].

Notably, this study also included assessments of patient satisfaction. The shorter hospital stay and higher satisfaction scores indicate better patient acceptance. Wang et al. pointed out that AngioJet is suitable for working populations requiring rapid recovery due to its concentrated treatment period, which helps shorten postoperative recovery time and improve adherence [12]. Chen et al. also suggested that hospital stay duration and bed rest restrictions are key factors affecting patient treatment experience, areas where AngioJet shows clear advantages [13].

Our logistic regression analysis further identified treatment modality (AngioJet) and symptom onset time ≤ 7 days as independent predictors of achieving Grade III thrombus clearance. This aligns with Guo et al., who emphasized that shorter thrombus age and earlier intervention enhance the efficacy of thrombolysis or aspiration [14], highlighting the critical importance of early recognition and intervention for improving treatment outcomes.

Nevertheless, this study has certain limitations. First, it is a single-center retrospective design with a limited sample size, which may introduce selection bias. Second, the 12-month follow-up period may be insufficient to fully reflect the long-term progression of PTS.

In summary, AngioJet offers higher thrombus clearance rates, shorter hospital stays, improved patient experience, and potential reduction in PTS incidence in the treatment of acute lower limb DVT. It is particularly suitable for patients with heavy thrombus burden, requiring rapid recovery or those intolerant to prolonged bed rest. Future multicenter, large-sample, long-term prospective studies are needed to further validate its potential in PTS prevention.

Author contributions

LW and HL designed the study. MC and CL extracted, collected, and analyzed data. MC prepared tables and figures. All authors reviewed the results, interpreted data, and wrote the manuscript. All authors approved the submission.

Funding

None.

Data availability

All data generated during the project will be made freely available via the Sanming Second Hospital’s Research Data Repository. DOIs to these data will be provided (as part of the DataCite programmed) and cited in any published articles using these data and any other data generated in the project. There are no security, licensing, or ethical issues related to these data. The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

Declarations

Ethical approval

This research did not increase the risk and economic burden of patients; the patients’ rights were fully protected. The ethical approval and participation consent followed the Helsinki Declaration guidelines. The ethical committee of Sanming Second Hospital reviewed and approved the research design and protocol (ID202011-202101-23).

Informed consent statement

All participants in this study have provided informed written consent prior to enrollment.

Competing interests

The authors declare no competing interests.