Catheter-directed thrombolysis through anterior tibial vein for treating acute extensive deep venous thrombosis

Application value of real-time shear wave elastography in the diagnosis and efficacy evaluation of venous thrombosis

BACKGROUND

Deep vein thrombosis (DVT) of the lower limbs is a venous reflux disorder caused by abnormal coagulation of blood components, primarily characterised by swelling and pain in the lower limbs. Key risk factors include prolonged immobility due to bed rest, pregnancy, postpartum or postoperative states, traumas, malignant tumours and long-term contraceptive use.

OBJECTIVE

To investigate the application of real-time shear wave elastography (SWE) in diagnosing lower-limb deep vein thrombosis (DVT).

METHODS

A total of 91 patients with DVT were selected and divided into three groups: acute phase (n= 29), subacute phase (n= 30) and chronic phase (n= 32). The Young's modulus of the patients was measured using real-time SWE. The diagnostic efficacy of Young's modulus was evaluated by ROC curves. The hardness differences in Young's modulus across different parts of the same thrombus (head, body and tail) were measured using SWE.

RESULTS

Before treatment, significant differences were observed in Young's modulus among patients with DVT (P< 0.001). Following anticoagulant therapy, catheter-directed thrombolysis and systemic thrombolysis, significant differences were noted in Young's modulus among patients at the same stage but receiving different treatments (acute phase: P= 0.003; subacute phase: P= 0.014; chronic phase: P= 0.004). Catheter-directed thrombolysis had greater efficacy than anticoagulant therapy. The area under the curve for SWE in staging patients was 0.917, with a sensitivity of 92.36% and specificity of 93.81%. Significant differences in Young's modulus were found between the thrombus head and thrombus body and tail but not between the thrombus body and thrombus tail.

CONCLUSION

Measurement of Young's modulus using SWE can serve as an auxiliary means of evaluating staging, predicting pulmonary embolism and selecting treatment in patients with DVT.

Comparative study of two different access points, one tibial vein and the popliteal vein, for catheter-directed thrombolysis in the treatment of acute mixed lower extremity deep vein thrombosis 1

BACKGROUND

Although the popliteal vein approach is commonly used for catheter-directed thrombolysis (CDT) treatment in patients with acute lower extremity deep vein thrombosis (DVT), CDT via a new access route, the posterior tibial vein, is also used and has demonstrated good results. However, this tibial approach has not been tested in large samples.

OBJECTIVE

To compare the early efficacy of CDT using the tibial and popliteal vein approaches for the treatment of acute mixed lower extremity DVT.

METHODS

In this retrospective cohort study, 87 patients with acute mixed lower extremity DVT treated at the Department of Interventional Medicine of Zhuhai People's Hospital were enrolled; those with tibial vein access and popliteal vein access were included in the observation (n = 55) and control (n = 32) groups, respectively. The safety and efficacy of CDT via tibial vein access were investigated by collecting and comparing indicators such as venous patency, thrombus removal effect, thigh and calf circumference difference, swelling reduction rate of the affected limb, surgical complications, and post-discharge complication rate of the patients in the two groups.

RESULTS

The postoperative thrombus clearance effect of the observation group was significantly better than that of the control group (P < 0.05), and the postoperative venous patency rate of the observation group was 83.2 ± 15.7%, which was higher than that of the control group (62.2 ± 38.2%) (P = 0.005). The swelling reduction rate of the lower extremity was 74.0 ± 33.8% in the observation group and 51.4 ± 30.0% in the control group, with a statistically significant difference (P = 0.002). However, there was no statistically significant difference (P > 0.05) in the rates of thigh swelling reduction, bleeding-related complications, or postoperative complications between the two groups of patients.

CONCLUSIONS

CDT via the tibial vein approach is safe, effective, and may be a better approach for CDT access, offering superior thrombus clearance, venous patency, and lower extremity swelling reduction postoperatively.

Calf deep veins are safe and feasible accesses for the endovascular treatment of acute lower extremity deep vein thrombosis

This study was designed to assess the optimal access route for the endovascular treatment of acute lower extremity deep vein thrombosis. This was a retrospective analysis of patients with acute lower extremity deep venous thrombosis who underwent endovascular treatment from February 2009 to December 2020. Patients underwent non-direct calf deep vein puncture (NDCDVP) from February 2009 to December 2011 and direct calf deep vein puncture (DCDVP) from January 2012 to December 2020. Catheter directed thrombolysis (CDT) was used to treat all patients in the NDCDVP group, whereas patients in the DCDVP group were treated with CDT or the AngioJet rhyolitic thrombectomy system. In patients exhibiting iliac vein compression syndrome, the iliac vein was dilated and implanted with a stent. Technical success rates and perioperative complication rates were compared between these two treatment groups. The NDCDVP group included 83 patients (40 males, 43 females) with a mean age of 55 ± 16 years, while the DCDVP group included 487 patients (231 males. 256 females) with a mean age of 56 ± 15 years. No significant differences were observed between these groups with respect to any analyzed clinical characteristics. The technical success rates in the NDCDVP and DCDVP groups were 96.4 and 98.2%, respectively (P > 0.05). In the NDCDVP group, the small saphenous vein (SSV)or great saphenous vein (GSV)were the most common access routes (77.1%, 64/83), whereas the anterior tibial vein (ATV) was the most common access route in the DCDVP group (78.0%, 380/487), followed by the posterior tibial vein (PTV) and peroneal vein (PV)(15.6% and 6.4%, respectively). Relative to the NDCDVP group, more patients in the DCDVP group underwent the removal of deep vein clots below the knee (7.2% [6/83] vs. 24.2% [118/487], P < 0.001). Moreover, relative to the NDCDVP group, significantly lower complication rates were evident in the DCDVP group (local infection: 10.8% vs. 0.4%, P < 0.001; local hematoma: 15.7% vs. 1.0%, P < 0.001). The position change rate was also significantly lower in the DCDVP group relative to the NDCDVP group (0% [0/487] vs. 60.2% [50/83], P < 0.001). The calf deep veins (CDVs) represent a feasible and safe access route for the endovascular treatment of lower extremity deep vein thrombosis.

Comparative outcomes of catheter-directed thrombolysis versus AngioJet pharmacomechanical catheter-directed thrombolysis for treatment of acute iliofemoral deep vein thrombosis

OBJECTIVE

The objective of this study was to compare the outcomes of pharmacomechanical thrombolysis and thrombectomy (PCDT) plus catheter-directed thrombolysis (CDT) vs CDT alone for the treatment of acute iliofemoral deep vein thrombosis (DVT) and summarize the clinical experience, safety outcomes, and short- and long-term efficacy.

METHODS

We performed a 4-year retrospective, case-control study. A total of 95 consecutive patients with acute symptomatic iliofemoral deep vein thrombosis (DVT) with a symptom duration of ≤7 days involving the iliac and/or common femoral veins underwent endovascular interventions. The patients were divided into two groups according to their clinical indications: PCDT plus CDT vs CDT alone. Statistical analyses were used to compare the clinical characteristics and outcomes between the two groups. Additionally, the patients were followed up for 3 to 36 months after treatment, and the proportions of post-thrombotic syndrome (PTS) and moderate to severe PTS were analyzed using the Kaplan-Meier survival method.

RESULTS

A total of 95 consecutive patients were analyzed in this retrospective study, of whom, 51 underwent CDT alone and 44 underwent PCDT plus CDT. Between the two groups, in terms of immediate-term efficacy and safety, significant differences were found in the catheter retention time (60.64 ± 12.04 hours vs 19.42 ± 4.04 hours; P < .001), dosages of urokinase required (5.82 ± 0.81 million units vs 1.80 ± 0.64 million units; P < .001), the detumescence rate at 24 hours postoperatively (48.46% ± 8.62% vs 76.79% ± 7.98%; P = .026), the descent velocity of D-dimer per day (2266.28 ± 1358.26 μg/L/D vs 3842.34 ± 2048.02 μg/L/D; P = .018), total hospitalization stay (6.2 ± 1.40 days vs 3.8 ± 0.70 days; P = .024), number of postoperative angiograms (2.4 ± 0.80 vs 1.2 ± 0.30; P = .042), and grade III venous patency (>95% lysis: 54.5% vs 68.6%; P = .047). Furthermore, during the follow-up period, significant differences were found in the incidence of PTS (Villalta scale ≥5 or a venous ulcer: 47.0% vs 27.7%; P = .037), and the incidence proportion of moderate to severe PTS at 12 months (15.7% vs 4.5%; P = .024) and 24 months (35.3% vs 11.4%; P = .016).

CONCLUSIONS

Compared with CDT alone, in the iliofemoral DVT subgroup with a symptom duration of ≤7 days, PCDT plus CDT could significantly relieve early leg symptoms, shorten the hospitalization stay, reduce bleeding complications, promote long-term venous patency, and decrease the occurrence of PTS and the incidence proportion of moderate to severe PTS. Thus, the short- and long-term outcomes both support the superiority of PCDT plus CDT vs CDT in this subgroup.

The Below-the-Knee Approach to Percutaneous Mechanical Thrombectomy for Lower Extremity Deep Venous Thrombosis: A Retrospective Single-Centre, Single-Arm Study

PURPOSE

The objective of this study was to evaluate the safety, efficacy, and feasibility of percutaneous mechanical thrombectomy (PMT) through a below-the-knee (BTK) approach for acute lower extremity deep venous thrombosis (DVT).

METHODS

A retrospective review of DVT patients treated with PMT by the BTK approach at our center from April 2022 to August 2023 was performed. Their preoperative demographics, intraoperative data, and postoperative outpatient outcomes were analyzed.

RESULTS

A total of 12 patients (67% men; mean age, 63 years) met the inclusion criteria. The BTK approach was successfully achieved in all patients through the posterior tibial vein (n = 1), anterior tibial vein (n = 2), and peroneal vein (n = 9). PMTs were achieved in 11 (92%) patients. Successful lysis (grade II and grade III lysis) was achieved in all patients with PMT. Four (33%) patients had residual venous occlusion over the popliteal vein. No intraoperative complications or bleeding events occurred in any of the patients.

CONCLUSION

PMT via BTK puncture seems to be a safe and effective approach for treating lower extremity DVT. It is reserved for highly select patients with a low risk of bleeding and is performed at centers that have experience with this procedure.

Central Venous Catheter as a Novel Approach to Postoperative Thrombolysis in Patients with Acute Iliofemoral Deep Venous Thrombosis

BACKGROUND AND AIMS

Percutaneous mechanical thrombectomy (PMT) along with postoperative thrombolysis (POT) has been the standard treatment for acute iliofemoral deep venous thrombosis (IFDVT). However, commonly used catheter directed thrombolysis (CDT) approaches for POT carry certain disadvantages, including the need for a sheath, inferior comfortability, and catheter-related complications. Therefore, we propose a new simplified method of POT using a central venous catheter (CVC).

METHODS

The retrospective study analyzed patients with IFDVT who underwent POT using CVC from January 2020 to August 2021. The treatment modalities included filter placement, thrombus removal, iliac vein obstruction release, postoperative CVC thrombolysis, filter retrieval, and adequate full course anticoagulation.

RESULTS

A total of 39 patients were included in this retrospective study. All patients underwent PMT surgery with a procedure success rate of 100%. In the post-PMT CVC thrombolysis, the puncture sites were located in the below-knee vein, including 58.97% in the peroneal vein. The mean duration of CVC-directed thrombolysis was 3.69 ± 1.08 days, and the total urokinase dose was 2.27 ± 0.71 MIU. A total of 37 patients (94.87%) had successful thrombolysis with a length of hospital stay of 5.82 ± 2.21 days. During CVC-directed thrombolysis, only four minor bleeding complications occurred, two of which were indwelling catheter-related. During the 12-month follow-up period, the patency rate and post-thrombotic syndrome incidences were 97.44% and 2.56%, respectively.

CONCLUSION

Thrombolysis through a CVC is a feasible, safe, and effective POT method, and could be an alternative to the conventional CDT approach for patients with IFDVT.

Clinical Observation of Uninterrupted Thrombolytic Therapy via Indwelling Catheter for Lower Limb Deep Vein Thrombosis

Purpose

Observe uninterrupted thrombolytic therapy via indwelling catheter for lower limb deep vein thrombosis.

Methods

We retrospectively studied data from 32 patients with lower extremity deep vein thrombosis who received comprehensive treatment, consisting of general treatment, inferior vena cava filter implantation, interventional thrombolysis, angioplasty, stenting, and post-operative monitoring.

Results

The efficacy and safety of the comprehensive treatment were observed for a follow-up period of 6-12 months. The treatment was 100% effective; patient results indicated no serious bleeding, acute pulmonary embolism, or death after surgery.

Conclusion

The combination of intravenous and healthy side femoral vein puncture and directed thrombolysis to treat acute lower limb deep vein thrombosis is safe, effective, and minimally invasive while still achieving a good therapeutic effect.

The incidence, risk factors, characteristics, and prognosis of recurrent deep venous thrombosis in the contralateral lower extremity

BACKGROUND

Recurrent events after a first symptomatic deep venous thrombosis (DVT) are relatively frequent, but little is known about contralateral recurrent DVT (RDVT).

METHODS

We retrospectively reviewed the medical records of patients with a first symptomatic lower extremity DVT between January 2017 and April 2021. The incidence, demographics, risk factors, and prognosis of RDVT were analyzed, with differences compared between patients with contralateral RDVT and those with ipsilateral RDVT.

RESULTS

In 570 consecutive patients with DVT, 28 patients (4.91%) developed contralateral RDVT, and 49 patients (8.60%) developed ipsilateral RDVT during a mean follow-up of 27.62 ± 14.84 months. Contralateral RDVT was more frequently found in the right lower extremity, whereas ipsilateral RDVT had more left lower extremity involvement. The median follow-up was 12 months until ipsilateral RDVT and 26.5 months until contralateral RDVT. In multivariate Cox analysis, inherited thrombophilia, stent extension with 50% to 100% coverage, autoimmune disease and anticoagulation noncompliance were identified as risk factors for contralateral RDVT. During follow-up, 5 patients (17.86%) with contralateral RDVT and 10 patients (20.41%) with ipsilateral RDVT died (P > .05), with 12 of 15 dying of an underlying malignancy.

CONCLUSIONS

The incidence of contralateral RDVT after a first symptomatic DVT is relatively low, and contralateral DVT is strongly associated with stent extension with 50% to 100% coverage, autoimmune disease, anticoagulation noncompliance, and inherited thrombophilia. Compared with ipsilateral RDVT, contralateral RDVT occurs later and is more often in the right lower extremity. Survival following contralateral RDVT is similar to survival following ipsilateral RDVT, with underlying malignancy being the leading cause of death.

Up-and-over access is not an optimal pathway for percutaneous catheter-directed thrombolysis in acute iliofemoral popliteal venous thrombosis

OBJECTIVE

To analyze the feasibility and results of up-and-over access (UOA) for catheter-directed thrombolysis (CDT) in acute iliofemoral popliteal venous thrombosis (IFPVT).

METHODS

From June 2020 to June 2021, a total of 26 patients (26 lower limbs) undergoing CDT for IFPVT were included. According to the vascular access, the patients were divided into UOA group (n = 11, 10 left limbs and 1 right limb) and ipsilateral popliteal vein (ILPV) (n = 15, 15 left limbs) access group. The differences in preoperative characteristics and technical details between the two groups were compared.

RESULTS

Patients in UOA group were older than those in ILPV access group (67.64 ± 4.11 years VS. 52.73 ± 15.63 years, p = .003). The BMI of UOA group was significantly higher than that of ILPV access group (26.03 ± 1.62 kg/m² VS 24.71 ± 1.46 kg/m², p = .039). There were significantly more patients with simultaneous three comorbidities in UOA group than in ILPV access group (45.5% vs. 0, p = .043). Compared with ILPV access group, the duration of operation and fluoroscopy of UOA group were significantly longer (20.64 ± 3.41 min vs. 10.20 ± 1.42 min, p < .001; 18.18 ± 2.99 min vs. 6.13 ± 0.92 min, p < .001), but the technical success rate was significantly lower (54.5% vs. 100%, p = .007). In UOA group, the operation-related complications occurred, including catheter straying into lateral sacral vein (9.1%), retroperitoneal hematoma (9.1%), and thrombus shedding into filter (9.1%).

CONCLUSION

The UOA may be attempted in patients who are unable to be prone, but this access is not an optimal pathway for CDT.

Percutaneous Mechanical Thrombectomy for Acute Symptomatic Iliofemoral Deep Venous Thrombosis Patients With Recent Aneurysmal Subarachnoid Hemorrhage

PURPOSE

To investigate the efficacy, safety, and mid-term outcomes of percutaneous mechanical thrombectomy (PMT) for acute symptomatic iliofemoral deep venous thrombosis (DVT) patients with recent (within 4 weeks) aneurysmal subarachnoid hemorrhage (aSAH).

MATERIALS AND METHODS

From January 2016 to February 2020, 11 acute symptomatic iliofemoral DVT patients with a recent history of aSAH were enrolled in this study. All patients had a history of aneurysm ligation or clipping previously, computed tomography (CT) scans revealed ventricular hemorrhage had been absorbed obviously and no residual aneurysm. The mean time of DVT onset after aSAH ictus was 19.2±4.5 days, and the mean Glasgow score was 6.8 ± 0.7 (range, 6-8). These patients underwent PMT with an 8 French Aspirex^®S device (Straub Medical AG, Wangs, Switzerland), subsequent stenting was performed to relieve the underlying stenosis, followed by anticoagulation alone. The procedure-related complications were assessed after intervention. The follow-ups were conducted up to 1 year, the patency was evaluated via duplex ultrasonography, and the incidence of post-thrombotic syndrome (PTS) was evaluated using the Villalta scale.

RESULTS

Grade III (>90%) clearance was achieved in all 11 patients. Stenting was performed in 7 patients (63.6%). There were no cerebral rebleeding events or other severe complications except 1 puncture site bleeding during treatment. A total of 90.9% (10 of 11) of patients were alive at the 12 month follow-up, and 7 patients achieved a good functional outcome. At the 1 year follow-up, there was 1 patient (10%) with mild PTS. The ultrasound showed that the patency of the iliofemoral veins was 100%, and femoral valvular incompetence was observed in 1 patient.

CONCLUSION

Percutaneous mechanical thrombectomy seems to be a feasible and safe treatment for acute iliofemoral DVT in selected patients with recent aSAH, and it shows promising results in restoring patency and reducing the risk of PTS.

Anatomical consideration of deep calf veins: application to catheter-directed thrombolysis

Purpose

An antegrade approach is frequently used in catheter-directed thrombolysis to remove deep-vein thrombosis. However, the antegrade approach is difficult when accessing veins with small diameters; therefore, understanding the variation of deep calf vein is important.

Methods

This study measured the diameters and surface areas of the proximal and distal posterior tibial vein, peroneal vein, and anterior tibial vein to determine which are preferable for venous access. This study dissected 132 legs from Korean and Thai cadavers. The proximal and distal posterior tibial vein, peroneal vein, and anterior tibial vein were scanned and measured.

Results

The mean diameter and surface area were largest for the proximal tibial vein, at 6.34 mm and 0.312 cm², respectively, followed by the anterior tibial vein (5.22 mm and 0.213 cm²), distal posterior tibial vein (3.29 mm and 0.091 cm²), and peroneal vein (3.43 mm and 0.081 cm²). The proximal posterior tibial vein and anterior tibial vein have large diameters and surface areas, which make them ideal for applying an antegrade approach in catheter-directed thrombolysis.

Conclusions

The distal posterior tibial vein and peroneal vein are not recommended due to their smaller surface areas and also the anatomical variations therein.

Comparing the efficacy of endovascular treatment for iliac vein compression syndrome with or without acute deep venous thrombosis: A single-center retrospective study

BACKGROUND

To compare the efficacy of endovascular treatment for iliac vein compression syndrome (IVCS) with or without acute deep venous thrombosis of lower extremity.

METHODS

This study retrospectively analyzed the clinical data of 300 IVCS patients, who received endovascular treatment between January 2013 and December 2017. According to whether IVCS was complicated by deep venous thrombosis or not, these patients were divided into non-thrombotic iliac vein lesion group (NIVL group, n = 127) and post-thrombotic iliac vein lesion group (PIVL group, n = 173). After endovascular treatment, all patients were followed up to assess the symptoms improvement and to evaluate the patency of iliac vein.

RESULTS

The technical success rate was 98% (294/300), and percutaneous transluminal angioplasty with stenting was adopted in 294 cases. The incidence of perioperative complications was 36.33% (109/300), but no severe complications occurred. During a mean follow-up of 22.3 months (range 6-30 months), 9(6.82%, 9/132) patients in PIVL group had recurrence of deep venous thrombosis, but nobody had deep venous thrombosis and varicose veins recurrence in NIVL group. The effective rate of endovascular treatment in NIVL group and PIVL group was 96.88% and 90.15% (P = 0.050), while the cumulative primary patency of iliac vein in NIVL group was significantly higher than that in PIVL group (P = 0.008).

CONCLUSIONS

The endovascular treatment is an effective, feasible, safe method for treating IVCS. There is no difference in the efficacy of IVCS patients with or without deep venous thrombosis, but the medium and long-term patency of patients with deep venous thrombosis is lower than that in patients without deep venous thrombosis.

Feasibility of anticoagulation using low molecular-weight heparin during catheter-directed thrombolysis for lower extremity deep venous thrombosis

Background

The optimal anticoagulant scheme during catheter-directed thrombolysis (CDT) for deep venous thrombosis (DVT) remains unknown. This study was performed to evaluate the feasibility of anticoagulation therapy using low molecular-weight heparin (LMWH) during CDT for DVT.

Methods

The clinical data of DVT patients who underwent CDT during the past six years was retrospectively collected and reviewed. Patients were divided into therapeutic-dose anticoagulation (TPDA) and sub therapeutic-dose anticoagulation (sub-TPDA) groups according to LMWH dosage.

Results

A total of 61 patients involving 61 limbs were comprised. Acute and subacute DVT were identified in 39 (63.9%) and 22 (36.1%) patients, respectively. Thrombosis involving the iliac vein was identified in 34 (55.7%) patients. Inferior vena cava filter placement was performed in 38 (62.3%) patients. Intraoperatively, adjunctive balloons, stents, and thrombectomy were provided for nine (14.8%), four (6.6%), and one (1.6%) patients, respectively. Twenty (32.8%) patients accepted TPDA therapy, while 41 (67.2%) patients were administrated with sub-TPDA therapy. Median urokinase infusion rate was 2.5 (0.83 to 5) × 10⁴ U/h. Median infusion duration time was 4 (2 to 14) days, and median urokinase dose infused was 2.4 (0.6 to 10.80) × 10⁶ U. During CDT, five (8.2%) cases of minor bleeding were observed, and blood transfusion was not required. No major bleeding, symptomatic pulmonary embolisms, or death occurred. Complete (> 90%) and partial thrombolysis (50 ~ 90%) were achieved in 56 (91.8%) patients. In comparison with sub-TPDA group, TPDA group exhibited no significant differences in baseline characteristics, clinical improvement, thrombolysis results, and complications.

Conclusions

Anticoagulation therapy using low molecular-weight heparin during CDT with low infusion rate for DVT is likely to be feasible and safe. Sub-therapeutic-dose anticoagulation and therapeutic-dose could be used for CDT with similar clinical outcome and bleeding complications.

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.

Is variation in posterior tibial veins a risk factor for deep-vein thrombosis?

INTRODUCTION

This study proposes variations in the posterior tibial vein as one of the risk factors for deep-vein thrombosis. Understanding the anatomical classification of the posterior tibial vein would guide the antegrade approach of catheter-directed thrombolysis.

MATERIALS AND METHODS

One hundred thirty-four legs from Korean and Thai cadavers were dissected. The posterior tibial veins were classified into four types according to the number of proximal and distal veins.

RESULTS

The most common type was type Ia (64/134), followed by type IIa (28/134), type Ib (24/134), and type IIb (16/134).

CONCLUSIONS

The anterior tibial and fibular veins had exactly two paired veins; however, the posterior tibial vein had many variations. We assume that patients with type IIb and IIa have a higher risk of thrombosis and hidden symptoms due to collateral formation. Additionally, the classification of the posterior tibial vein and dividing into proximal and distal posterior tibial vein would help practitioners predict the course and guide the application of catheter-directed thrombolysis.

Outcome of AngioJet mechanical thrombus aspiration in the treatment of acute lower extremities deep venous thrombosis

OBJECTIVES

The objective of this study was to evaluate the efficacy and safety in patients with acute lower extremity deep venous thrombosis who underwent pharmacomechanical thrombectomy (PMT, AngioJet mechanical thrombus aspiration).

METHODS

In this retrospective, 424 consecutive patients with acute lower extremity deep venous thrombosis from three institutions were enrolled in the study from January 2015 to December 2018. Of these, patients were divided into two groups, AngioJet group (n = 186) and catheter-directed thrombolysis (CDT) group (n = 238). Evaluation indexes including limb circumference difference, length of stay (LOS), urokinase dosage, periprocedural complications, follow-up imaging findings and villalta scores were analyzed from the medical records.

RESULTS

A total of 424 patients diagnosed with acute lower extremity deep venous thrombosis were collected in this study. These patients were categorized into AngioJet group and CDT group. Significant differences were observed between the two groups with respect to the thigh circumference difference (5.32 ± 1.85 cm vs. 4.69 ± 2.15 cm; p = 0.04), calf circumference difference (2.79 ± 1.54 cm vs. 2.35 ± 1.25 cm; p = 0.01), thigh detumescence rate (72.19 ± 19.55% vs. 65.35 ± 17.26%; p = 0.00) and calf detumescence rate (62.79 ± 18.56% vs. 55.75 ± 17.27%; p = 0.00). The mean dose of urokinase in AngioJet group was 95.16 ± 45.89 million IU significantly less than that in the CDT group 293.76 ± 42.71 million IU (p = 0.00). The overall bleeding complication rate was 9.91% (19 patients in AngioJet group and 23 patients in CDT group), which included three major (0.71%, 3/424) and 39 minor (9.2%,39/424) events. In the AngioJet group, serum creatinine (sCr) concentration and urine erythrocyte from the hemolysis caused by the mechanical process were higher than baseline data at admission (p = 0.00, p = 0.00). The postoperative red blood cell and hemoglobin in two groups were lower than baseline data (p = 0.00, p = 0.00). Compared with CDT, AngioJet thrombectomy has significantly lower estimated incidence of PTS in the follow-up.

CONCLUSION

AngioJet thrombectomy has stronger clearance ability for acute lower extremity deep venous thrombosis leading to significant reduction in the consumption of hospital resources, total dose of thrombolytic agents, and infusion time, thereby preventing adverse bleeding events, but patients with renal insufficiency should be careful. Ideal short-term and medium-term efficacy and safety are certain.

The short-term outcome of residual thrombus of the lower extremity after pharmacomechanical catheter-directed thrombolysis for deep vein thrombosis

Background

This study aimed to assess the short-term effect of residual thrombus of the lower extremity after pharmacomechanical catheter-directed thrombolysis (PCDT) on the incidence of post-thrombotic syndrome (PTS) and iliofemoral vein patency rate in patients who underwent PCDT.

Methods

There were 94 continuous patients with severe deep vein thrombosis (DVT) of the lower extremities admitted to our hospital between March 2016 and June 2018; 73 cases receiving PCDT and verified with iliac vein compression syndrome (IVCS) were assigned into two groups. Thirty-nine patients without thrombus of the popliteal and infrapopliteal veins were assigned to the proximal DVT group. The remaining 34 cases were placed in the extensive DVT group. The thrombus scores, including venous registry index (VRI) score, Marder score, and Society for Vascular Surgery (SVS) score before and after PCDT, the primary two years’ cumulative rate of iliofemoral patency, and the rate of PTS, and complications were analyzed retrospectively.

Results

Ultimately, 27 patients in the proximal DVT group and 26 cases in the extensive DVT group completed the study. The two groups had no significant differences in terms of basic characteristics, complication and the rate of PTS (P>0.05). However, there were significant differences in terms of postoperative mean thrombus score and the mean degree of thrombosis removal score by Marder and SVS scores, residual thrombus by lower thrombosis classification (LET) and the two years’ cumulative iliofemoral vein patency rate (P<0.05). And the logistic regression analysis demonstrated the residual thrombus of LET class II [odds ratio (OR), 4.619, 95% confidence interval (CI), 1.090–19.567, P=0.038] was an independent risk factor for iliofemoral vein occlusion.

Conclusions

The residual thrombus of LET class II is an independent risk factor for iliofemoral vein occlusion. It is very important to keep the patency of the popliteal vein when deciding to use a stent to maintain iliofemoral vein patency. Furthermore, the anterior tibial vein approach and crisscross technique may be two important alternative methods that can be used to address the thrombus of popliteal vein for patients with extensive DVT.