Acute Lower Extremity Deep Vein Research Articles

Early Thrombus Removal for Acute Lower Extremity Deep Vein Thrombosis: Update on Inclusion, Technical Aspects, and Postprocedural Management.

Acute lower extremity deep vein thrombosis (DVT) is a common disorder with significant associated morbidity, including pain and swelling, as well as the risk of pulmonary embolism (PE), recurrent venous thromboembolism (VTE) and chronic debilitating post-thrombotic syndrome (PTS). Anticoagulation is standard of care for DVT treatment. It assists in reducing thrombus progression and the occurrence of PE, but incomplete DVT resolution increases the risk of recurrent VTE, valvular insufficiency, and PTS. Endovascular DVT interventions, such as catheter-directed thrombolysis, pharmacomechanical thrombectomy, and large-bore mechanical thrombectomy offer an alternative therapeutic strategy for DVT management. This paper will discuss technical factors and current issues when performing lower extremity DVT interventions including patient selection, anticoagulation, choice of device for endovascular thrombus removal, adjunctive techniques, and venous stent management.Level of Evidence: No level of evidence for: review articles, basic science, laboratory investigations, and experimental study articles.

Analysis of risk factors for post-thrombotic syndrome after thrombolysis therapy for acute deep venous thrombosis of lower extremities

ObjectiveThe purpose of the research is to explore post-thrombotic syndrome (PTS) after catheter-directed thrombolysis (CDT) treatment for acute lower extremity deep vein thrombosis (DVT) risk factors. MethodsWe retrospectively selected 171 patients with acute lower extremity DVT undergoing CDT treatment, collected clinical data of the patients, grouped them according to the follow-up results of 1 year after treatment, and included patients with PTS into the concurrent group and patients who did not develop PTS assigned to the unconcurrent group. Univariate analysis and Logistic regression were applied to analyze the risk factors of PTS after catheterization and thrombolytic therapy for acute lower extremity DVT. We applied R4.2.3 software to build three hybrid machine-learning models, including a nomogram, decision tree, and random forest with independent influencing factors as predictive variables. ResultsThe incidence of PTS after CDT in acute lower extremity DVT was 36.84 %. BMI >24.33 kg/m2, disease time >7 d, mixed DVT, varicose vein history, stress treatment time>6.5 months, and filter category were independent risk factors for PTS after CDT treatment for acute lower extremity DVT. The AUC value predicted by the random forest model was higher than that of the nomogram model (Z = -2.337, P = 0.019) and the decision tree model (Z = -2.995, P = 0.003). ConclusionThe occurrence of PTS after CDT treatment of acute lower extremity DVT is closely related to many factors, and the established random forest model had the best effect in predicting PTS complicated with PTS.

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

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. In this article, we compare the early efficacy of CDT using the tibial and popliteal vein approaches for the treatment of acute mixed lower extremity DVT. 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 postdischarge complication rate of the patients in the 2 groups. 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 2 groups of patients. 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.

Current Evidence for Endovascular Therapies in the Management of Acute Deep Vein Thrombosis.

Acute lower extremity deep vein thrombosis (DVT), specifically proximal iliofemoral DVT, is a relatively common disorder that can result in a chronic debilitating post-thrombotic syndrome (PTS), with a significant effect on a patient's quality of life. Anticoagulation is first-line therapy; however, percutaneous interventions have emerged as treatment options for patients where there is concern that anticoagulation alone will not resolve the DVT as well as prevent PTS. This paper will discuss the existing data on these interventions and review current endovascular techniques, including catheter-directed thrombolysis, pharmacomechanical thrombectomy, and large-bore mechanical thrombectomy in the management of DVT.

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.

Overall Survival of Warfarin Compared to LMWH/Doacs in Cancer-Associated Venous Thromboembolism: VA Cohort Study

Background: Warfarin has been shown in pre-clinical models to have anti-neoplastic activity. In a population-based study using the SEER-Medicare Linked Database warfarin was associated with improved survival compared to low molecular weight heparin (LMWH) or direct oral anticoagulants (DOACs) in the treatment of cancer-associated thrombosis (CAT). To assess whether the observed survival advantage is consistent in other large cohorts, we performed a matched cohort study utilizing the Veterans Affairs (VA) database. The VA is a large, integrated health care system with comprehensive data for their patients at the individual level, which provides the optimal observational cohort to confirm the novel hypothesis warfarin confers a mortality benefit over LMWH. Method: Using the retrospective data from the VA health care system from 2000-2021, we identified patients with CAT who were &amp;gt; 18 years, had available prescription data for anticoagulation within 30 days of venous thromboembolism (VTE), and survived &amp;gt; 14 days after the index VTE event. Patients were excluded if they had prior diagnosis of VTE or had any anticoagulation prescription prior to the first coded VTE event. The primary outcome was overall survival (OS). Patients were matched 1:1 using nearest neighbor matching on the propensity score. The matching variables included cancer site, cancer stage, date of cancer diagnosis, date of VTE diagnosis, age at VTE diagnosis, gender, race, BMI, Elixhauser-based weighted comorbidity score, and rurality of residential status. Cox proportional-hazards regression was performed to estimate hazard ratios (HR) and 95% confidence intervals. Log-rank test was utilized to estimate the p-value. Subgroup analyses were performed in the largest groups of cancer available in the data set including prostate cancer, lung cancer, gastrointestinal cancer (excluding hepatobiliary cancer), and malignant hematologic neoplasms (including myeloid malignancy, lymphoid malignancy, and multiple myeloma). Finally subgroup analysis was also performed on localized cancer and metastatic disease based on AJCC stage grouping. Result: There were a total of 20,078 patients that met the inclusion and exclusion criteria without missing data. The warfarin cohort consistent of 8383 patients while non-warfarin cohort comprised 11696 patients. Among the non-warfarin cohort, 54% of the patients were prescribed LMWH exclusively and 38% of the patients were prescribed DOAC exclusively within 30days of the VTE diagnosis. The most common malignancies in the cohort included prostate (29.4%), lung (20.9%), gastrointestinal (15.7%) and hematologic malignancies (10.3%). Of patients with solid tumors, 22% had metastatic cancer. Among the VTE events, 33.3% were acute lower extremity deep vein thrombosis, 48.4% were acute pulmonary embolism, and 18.3% were acute upper extremity deep vein thrombosis. After propensity score matching, 8,383 patients were included in the warfarin arm and 8,383 patients in the non-warfarin arm. The median age at VTE diagnosis of the matched cohort was 69 [IQR 63 - 75] and the majority of the patients (96.7%) were male. Warfarin was associated with a significant improvement in OS compared to non-vitamin K antagonists (median OS, 1204 days [95% CI, 1137-1276 days] vs 703 days [95% CI, 665-747 days]; HR 0.79 [95% CI 0.76 - 0.82]; p-value &amp;lt;2x10 -16) (Figure1). The difference was also preserved in gastrointestinal malignancy (HR 0.8 v95% CI 0.73-0.87), lung cancer (HR 0.8, 95% CI 0.79-0.92) and prostate cancer (HR 0.71, 95% CI 0.65-0.77). The survival advantage was preserved in patients with metastatic (HR 0.86, 95% CI 0.78-0.83) and localized cancer (HR 0.80, 95% CI 0.76-0.84) (Figure 2). Conclusion and Relevance: In a population level propensity matched study, warfarin for the treatment of CAT was associated with significantly improved survival over non-vitamin K antagonist anticoagulation in CAT. These provocative finding confirm the previous observation in SEER-Medicare database and have important implications on patient care and health care costs. Further investigation into the biological basis of these findings could potentially lead to biomarker and drug discovery for cancer therapies and prognostication.

Racial and ethnic disparities in inferior vena cava filter placement for deep vein thrombosis in the United States

ObjectiveWe sought to determine whether racial and ethnic disparities existed in inferior vena cava (IVC) filter (IVCF) placement rates among Black and Latino patients for the treatment of acute proximal lower extremity (LE) deep vein thrombosis (DVT) in the United States from 2016 to 2019. MethodsWe performed a retrospective review of National Inpatient Sample data to identify adult patients with a primary discharge diagnosis of acute proximal LE DVT from January 2016 to December 2019, including self-reported patient race and ethnicity. IVCF placement rates were identified using International Classification of Diseases, 10th revision, codes. Weighted multivariable logistic regression was used to compare IVCF use by race and ethnicity. The regression model was adjusted for patient demographics (ie, sex, primary payer, quartile classification of household income), hospital information (ie, region, location, teaching status, bed size), weekend admission, and clinical characteristics (ie, modified Charlson comorbidity index, hypertension, atrial fibrillation, diabetes mellitus type 2, congestive heart failure, dyslipidemia, coronary artery disease, smoking, obesity, alcohol abuse, chronic kidney disease, pulmonary embolism, malignancy, contraindications to anticoagulation, including other major bleeding). ResultsOf 134,499 acute proximal LE DVT patients, 18,909 (14.1%) received an IVCF. Of the patients who received an IVCF, 12,733 were White (67.3%), 3563 were Black (18.8%), and 1679 were Latino (8.9%). IVCF placement decreased for all patient groups between 2016 and 2019. After adjusting for the U.S. population distribution, the IVCF placement rates were 11 to 12/100,000 persons for Black patients, 7 to 8/100,000 persons for White patients, and 4 to 5/100,000 persons for Latino patients. The difference in IVCF placement rates was statistically significant between patient groups (Black patients vs White patients, P < .05; Black patients vs Latino patients, P < .05; Latino patients vs White patients, P < .05). ConclusionsThis nationwide study showed that Black patients have higher IVCF placement rates compared with White and Latino patients. Given the known long-term complications and uncertain benefits of IVCFs, coupled with the 2010 U.S. Food and Drug Administration safety warning regarding adverse patient events for these devices, proactive measures should be taken to address this disparity among the Black patient population to promote health equity. Future work should assess whether clinician bias might be perpetuating this disparity.

Outcomes from the ClotTriever Outcomes Registry show symptom duration may underestimate deep vein thrombus chronicity: Presented at Eastern Vascular Society meeting, September 23-26, 2021, Charleston, SC.

Objective: The all-comer ClotTriever Outcomes registry assessed indicators of thrombus chronicity in patients with acute, subacute, and chronic lower extremity deep vein thrombosis (DVT). The effectiveness of the ClotTriever System (Inari Medical, Irvine, CA) by chronicity subgroup was also assessed and reported here in this subanalysis.

Risk factors and outcomes regarding the acute kidney injury after AngioJet thrombectomy for acute lower-extremity deep vein thrombosis

ObjectiveTo investigate the risk factors and outcomes regarding acute kidney injury (AKI) after AngioJet thrombectomy for acute lower-extremity deep vein thrombosis (DVT). MethodsPatients were divided into AKI and non-AKI groups according to whether AKI occurred postoperatively. The demographic data, pre-operative and post-operative laboratory data and surgical differences were compared between the two groups. Logistic regression and Wilcoxon signed-rank test were used to identify the AKI risk factors and outcomes, respectively. ResultsAmong the 341 patients who met the inclusion criteria, 45 developed AKI (AKI group) and 296 had normal renal function (non-AKI group) post-surgery. There were significant differences between the two groups in the course (t = 10.885, P = 0.000); preoperative history of a major surgery within 3 months (3M-MS) (odds ratio [OR] = 5.492, P = 0.001); duration of aspiration thrombectomy (Z = −8.803, P = 0.000); volumes of aspiration (Z = −8.215, P = 0.000); contrast volume (Z = −3.204, P = 0.001) and pulmonary thrombectomy (OR = 18.200, P = 0.002); and preoperative complications of hypertension (OR = 4.637, P = 0.002), diabetes (OR = 18.088, P = 0.000), or pulmonary embolism (OR = 0.085, P = 0.011). Wilcoxon signed-rank test showed that the renal function of every patient in the AKI group returned to normal 3 months after the surgery. ConclusionsThe course, preoperative complications of diabetes or hypertension, 3M-MS, contrast volume, duration and volume of aspiration thrombectomy, and pulmonary thrombectomy are risk factors for post–AngioJet-thrombectomy AKI, which is temporary.

Endovascular Management of Acute Iliofemoral Deep Vein Thrombosis: Who Benefits?

Endovascular therapy (ET) for acute lower extremity deep vein thrombosis (DVT) to mitigate downstream postthrombotic syndrome (PTS) has garnered considerable attention, reflected by the significant growth in clinical interest and proliferation of venous-specific thrombectomy devices. Numerous single-arm or retrospective studies examining the role of DVT thrombolysis/thrombectomy have been published. However, the landmark Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis (ATTRACT) trial is the largest and most rigorous investigation to date on whether ET, particularly pharmacomechanical catheter-directed thrombectomy/thrombolysis (PCDT), resulted in the prevention of PTS (1).

Interim outcomes of mechanical thrombectomy for deep vein thrombosis from the All-Comer CLOUT Registry: Presented at the Thirty-fifth Annual Eastern Vascular Symposium of Twenty-second Annual New Cardiovascular Horizons, New Orleans, Louisiana, June 1-4, 2021, and the Eastern Vascular Society, Charleston, South Carolina, September 23-23, 2021.

Objectives: The multicenter, prospective, single arm CLOUT registry assesses the safety and effectiveness of the ClotTriever System (Inari Medical, Irvine, CA) for the treatment of acute and nonacute lower extremity deep vein thrombosis (DVT) in all-comer patients. Reported here are the outcomes of the first 250 patients.

Outcomes from the ClotTriever Outcomes Registry show symptom duration may underestimate deep vein thrombus chronicity

ObjectiveThe all-comer ClotTriever Outcomes registry assessed indicators of thrombus chronicity in patients with acute, subacute, and chronic lower extremity deep vein thrombosis (DVT). The effectiveness of the ClotTriever System (Inari Medical, Irvine, CA) by chronicity subgroup was also assessed and reported here in this subanalysis. MethodsAll-comer patients with lower extremity DVT were enrolled, with no limitation based on the patients’ symptom duration. Chronicity was assessed three times and compared: before the procedure based on symptom duration, during the procedure based on available pre-thrombectomy imaging, and visual inspection of the extracted thrombus morphology after thrombectomy. Patients were grouped into acute, subacute, and chronic subgroups according to their post-thrombectomy thrombus chronicity based on thrombus morphology. Analyses on baseline and procedural characteristics along with thrombus removal were performed across subgroups. The effectiveness of thrombus removal was determined by Marder scores adjudicated by an independent core laboratory, with a prespecified primary effectiveness end point of complete or near-complete (≥75%) thrombus removal. ResultsOf the 260 treated limbs from 250 patients, using symptom duration alone, 70.7% were considered acute, 20.9% subacute, and 8.4% chronic. Upon visual inspection, the extracted thrombus chronicity was approximately one-third in each subgroup: 32.7% had acute thrombus, 35.4% subacute thrombus, and 31.9% chronic thrombus. Chronicity assessed using symptom duration alone mismatched the post-thrombectomy chronicity in 55.1% of limbs (P < .0001) with 49.0% being more chronic than suggested by the patients’ duration of symptoms. Chronicity assessed using pre-thrombectomy imaging mismatched the post-thrombectomy chronicity in 17.5% of limbs (P < .0001). No patients received thrombolytics and 99.6% were treated in a single session. Complete or near-complete thrombus removal was achieved in a high percentage of limbs regardless of thrombus chronicity: 90.8%, 81.9%, and 83.8% in limbs with acute, subacute, and chronic thrombus, respectively. ConclusionsThis subanalysis from the all-comer ClotTriever Outcomes registry demonstrates that extracted thrombus in DVT may be more chronic than suggested by the patients’ duration of symptoms. The addition of imaging is helpful to determine the ability of thrombus to respond to therapy. Irrespective of thrombus chronicity, the ClotTriever system can be effective at removing acute, subacute, and chronic thrombus in a single-session procedure without the need for thrombolytics.

Concomitant acute lower extremity arterial and deep vein thrombosis developing in a patient under anticoagulant therapy after COVID 19 infection.

The hypercoagulable state continues after the Coronavirus 2019 (Covid 19) infection and prophylactic anticoagulants are recommended in this period. However, arterial and venous thromboembolic events can be observed during the convalescence period after the Covid 19. Here, we present the case of acute lower extremity arterial and venous thromboembolism developed in the post-Covid 19 period in a 77-years-old patient, under therapeutic doses of anticoagulant therapy (enoxparin 1mg/kg of weight every 12 hours). The patient, who had no previous history of arterial or venous thrombosis, was taken to emergency surgery with the diagnosis of ALI (acute limb ischemia) due to acute arterial thrombosis. An arterial thrombectomy was performed with the help of a 4F Fogarty catheter inserted from the left femoral artery under local anesthesia. All distal pulses of the patient were palpable in the postoperative period. After the platelet count became &gt;100,000 mm3, 100 mg of acetylsalicylic acid daily was added to the therapeutic dose of enoxaparin sodium treatment. The patient was discharged, uneventfully, except for a minimal diameter increase secondary to deep venous thrombosis (DVT) on the fifth postoperative day, with a combination of enoxaparin and acetylsalicylic acid treatment. Endothelial injury, chronic immuno-thrombogenicity, and increased platelet aggregation in the post-Covid 19 recovery period can cause major thrombotic events, even weeks after the recovery. Anticoagulant therapy is recommended for thromboprophylaxis when the following statuses exist: ≥65 years, critical illness, cancer, prior VTE, thrombophilia, severe immobility, and elevated Ddimer. Combination treatment with long-term antiaggregant therapy may be prudent in thromboembolic events developed under anticoagulant therapy.

Defining the role of risk stratification and duplex ultrasound in the diagnosis of acute lower extremity deep vein thrombosis

ObjectiveRisk stratification using the plasma D-dimer level and Wells score has been proposed as a safe strategy to rule out acute lower extremity deep vein thrombosis (DVT) and limit the use of duplex ultrasound (DUS) for low-risk patients. A widely used diagnostic protocol defining the role of pretest probability and D-dimer testing in lieu of DUS has not been reported. Our aim was to define the risk of DVT in a standard population of emergency department patients who had presented with acute lower extremity symptoms and determine the role of DUS for these patients. MethodsOutpatients presenting to the emergency department with symptoms concerning for lower extremity DVT were prospectively enrolled. All the patients underwent whole leg DUS and clinical and laboratory assessments for DVT using the Wells criteria and plasma D-dimer testing. The patients were stratified into three groups according to the combination of their Wells score and plasma D-dimer level. The prevalence of DVT and the statistical performance of the combined Wells score and plasma D-dimer were compared. ResultsA total of 3087 patients were enrolled. Most of the patients had had a negative plasma D-dimer level and Wells score (n = 2290 patients). A total of 222 patients had had a positive plasma D-dimer level and Wells score. The overall prevalence of acute DVT in the present study was 7.3%. Of the 2290 patients with a negative Wells score and negative plasma D-dimer level, 4 had had a diagnosis of DVT (negative predictive value, 99.8%). In contrast, DVT was present in 181 of 222 patients (81.5%) with a positive Wells score and plasma D-dimer level (positive predictive value, 81.5%). The plasma D-dimer level also correlated with the DVT location, and the D-dimer levels were highest for the patients with proximal DVT. ConclusionsThe combination of a negative Wells score and negative plasma D-dimer level can safely exclude the presence of DVT. Patients with a negative Wells score and negative plasma D-dimer level are unlikely to benefit from DUS. In contrast, patients with a positive D-dimer level and positive Wells score will benefit from whole leg DUS to rule out the presence of high-risk DVT.

Interim outcomes of mechanical thrombectomy for deep vein thrombosis from the All-Comer CLOUT Registry

ObjectivesThe multicenter, prospective, single arm CLOUT registry assesses the safety and effectiveness of the ClotTriever System (Inari Medical, Irvine, CA) for the treatment of acute and nonacute lower extremity deep vein thrombosis (DVT) in all-comer patients. Reported here are the outcomes of the first 250 patients. MethodsAll-comer patients with lower extremity DVT were enrolled, including those with bilateral DVT, those with previously failed DVT treatment, and regardless of symptom duration. The primary effectiveness end point is complete or near-complete (≥75%) thrombus removal determined by independent core laboratory-adjudicated Marder scores. Safety outcomes include serious adverse events through 30 days and clinical outcomes include post-thrombotic syndrome severity, symptoms, pain, and quality of life through 6 months. ResultsThe median age was 62 years and 40% of patients had contraindications to thrombolytics. A range of thrombus chronicity (33% acute, 35% subacute, 32% chronic) was observed. No patients received thrombolytics and 99.6% were treated in a single session. The median thrombectomy time was 28 minutes. The primary effectiveness end point was achieved in 86% of limbs. Through 30 days, one device-related serious adverse event occurred. At 6 months, 24% of patients had post-thrombotic syndrome. Significant and sustained improvements were observed in all clinical outcomes, including the Revised Venous Clinical Severity Score, the numeric pain rating scale, and the EuroQol Group 5-Dimension Self-Report Questionnaire. ConclusionsThe 6-month outcomes from the all-comer CLOUT registry with a range of thrombus chronicities demonstrate favorable effectiveness, safety, and sustained clinical improvements.

Learning curve for percutaneous thrombectomy in treatment of acute lower extremity deep vein thrombosis

ObjectiveWe evaluated the effect of the learning curve on percutaneous thrombectomy (PT) outcomes for the treatment of lower extremity deep vein thrombosis (DVT). MethodsThe present study was conducted between October 2019 and September 2020 and included 80 patients who had undergone PT to treat lower extremity DVT of the common iliac, external iliac, common femoral, femoral, and popliteal veins. For thrombectomy, aspiration and mechanical thrombectomy procedures were performed until the thrombus had completely dissolved using the Dovi aspiration system and Mantis mechanical thrombectomy system (Invamed, Ankara, Turkey). A total of 80 patients were divided equally into four groups, with the first 20 cases in group 1, the second 20 cases in group 2, the third 20 cases in group 3, and the final 20 cases in group 4. The groups were compared for the demographic characteristics, intraoperative outcomes, complication rates, and procedure success. ResultsAll demographic parameters were similar between the four groups. The mean operative time was 139.3 minutes for group 1, 134.8 minutes for group 2, 111.3 minutes for group 3, and 106.7 minutes for group 4. Statistical analysis revealed that the operative time was significantly shorter for groups 3 and 4 compared with that for groups 1 and 2. In addition, the fluoroscopy time was significantly decreased in groups 3 and 4 (P = .001). The complication rate was similar between the four groups (P = .899). However, success was significantly increased after the first 20 cases, and the remaining three groups had a significantly higher success rate compared with group 1 (70% for group 1, 90% for group 2, 95% for group 3, and 100% for group 4; P = .024). ConclusionsSuccess in the performance of PT for the treatment of acute lower extremity DVT reaches satisfactory levels after 20 cases. Additionally, operation time and fluoroscopy time are significantly decreased after 40 cases and then start plateau.

Patients With Right Lower Extremity Deep Vein Thrombosis Have a Higher Risk of Symptomatic Pulmonary Embolism: A Retrospective Study of 1585 Patients

To determine the risk for pulmonary embolism (PE) and explore the relationship between the site of thrombosis and PE in patients with acute lower extremity deep vein thrombosis (DVT). A total of 1585 hospitalized patients first diagnosed with acute lower extremity DVT were investigated retrospectively. The patients were divided into two groups: the non-PE group (Group 1) and the PE group (Group 2). Then, Group 2 was divided into two subgroups: asymptomatic pulmonary embolism (asPE, Group 2a) and symptomatic pulmonary embolism (sPE, Group 2b). Kaplan-Meier curves and logistic regression analysis were used to explore the relevant risk factors for PE. Among 1585 patients, 458 patients suffered from PE, accounting for 28.9%. 102 (22.3%) of them had the typical clinical manifestations of PE and were defined as sPE, and the remaining 356 (77.7%) patients were classified as asPE. Patients with proximal lower extremity DVT were significantly more predominant in the PE group than in the non-PE group (92.8% vs. 86.2%, P<0.001). Moreover, in Group 2, patients with typical PE manifestations showed a higher proportion of patients with right lower extremity DVT than left lower extremity DVT (26.7% vs. 17.7%, P=0.035), and bilateral lower extremity DVT than unilateral DVT (44.1% vs. 20.5%, P<0.001). By multivariate analysis, alcohol consumption (OR, 1.824; 95% CI, 1.194-2.787; P=0.005), heart failure (OR, 2.345; 95% CI, 1.560-3.526; P<0.001), proximal DVT (OR, 2.096; 95% CI,1.407-3.123; P<0.001) were independent risk factors for PE. Patients with proximal acute lower extremity DVT were more likely to suffer from PE than those with distal DVT. Patients with right acute lower extremity DVT had a higher risk of sPE than patients with left acute lower extremity DVT. Alcohol consumption and heart failure were associated with the occurrence of PE in patients with acute lower extremity DVT.

Wells Clinical Probability and D-dimer Testing: Risk Stratification for Acute Lower Extremity Deep Vein Thrombosis

Current vascular guidelines recommend duplex ultrasound (DUS) to rule out acute lower extremity deep vein thrombosis (DVT). The combined use of D-dimer levels with Wells clinical probability scores has been proposed as an alternative method to exclude DVT and minimize the use of DUS in low-risk patients. We hypothesized that high-risk patients who would benefit from further evaluation for DVT with DUS can be reliably identified using a combination of the plasma D-dimer level and Wells score. A prospective observational study was performed. Outpatients presenting to the emergency department with a chief complaint concerning for acute lower extremity DVT underwent risk stratification into three groups on the basis of pretest probability using the Wells score and plasma D-dimer level. All patients were evaluated with whole leg ultrasound to the confirm diagnosis. Of 3087 patients, 74.2% were classified as low risk, 18.6% as moderate risk, and 7.2% as high risk. The prevalence of DVT was 7.3% on completion of DUS. The negative predictive value for a negative D-dimer level and negative Wells score was 99.8%. A positive D-dimer level with a positive Wells score had a sensitivity and specificity of 97.4% and 91.9% for DVT, respectively. The plasma D-dimer levels correlated with the DVT level (η2 = 0.22) and were highest in those with proximal DVT. The combined use of the Wells clinical probability score and plasma D-dimer level is a safe and effective method of risk stratifying emergency room patients with lower extremity symptoms concerning for acute DVT. Patients with a low probability Wells score and negative plasma D-dimer level are unlikely to benefit from DUS, and patients with a positive D-dimer level and Wells score would benefit from whole leg DUS to rule out high-risk thrombi.

Cost-effectiveness Analysis of AngioJet and CDT for Lower Extremity Deep Vein Thrombosis Among Chinese Population.

AngioJet has sufficient safety and efficacy in the treatment of acute and subacute lower extremity deep vein thrombosis (LEDVT). But the price of consumables used by AngioJet is relatively high and there is a lack of relevant research on health economics to measure the benefits to patients. Objective of this study is to estimate the cost effectiveness of AngioJet compared with catheter-directed thrombolysis (CDT) among Chinese population. Using a Markov decision model, we compared the 2 treatment strategies in patients with LEDVT. The model captured the development of post-thrombotic syndrome (PTS), recurrent venous thromboembolism, and treatment-related adverse events within a lifetime horizon and the perspective of a third-party payer. Model uncertainty was assessed with one-way and Monte Carl sensitivity analyses. The clinical inputs were obtained from the literature. Costs obtained from the hospital accounts and the literature are expressed in US dollars ($). Utilities were defined as quality adjusted life years (QALY). In cost-effectiveness analysis, AngioJet accumulated $1064.6445/QALY compared with $2080.1561/QALY after CDT treatment alone. AngioJet has higher long-term cost-effectiveness than CDT at a willingness to pay threshold of $11 233.52. One-way sensitivity analysis showed that the utilities of PTS and post-LEDVT state had significant influence on the results and the model maintained a strong stability under ± 10% fluctuation of utilities. Monte Carl sensitivity analysis shows that AngioJet model has strong stability and AngioJet has higher long-term cost-effectiveness than CDT. AngioJet is likely to be a cost-effective alternative to the CDT for patients with LEDVT.

A pilot randomized trial of atorvastatin as adjunct therapy in patients with acute venous thromboembolism.

Venous thromboembolism (VTE) is the third most common cardiovascular disease and optimizing treatment is essential. In this single-center pilot study, we sought to investigate the effects of statins in addition to anticoagulation in patients with acute VTE. We enrolled patients over 18 with an acute proximal lower extremity deep vein thrombosis with or without pulmonary embolism. Patients were randomized to anticoagulation alone (with either warfarin or rivaroxaban) or anticoagulation and atorvastatin 40 mg daily and followed for 9 months. The primary objective was to determine if adjunct atorvastatin reduced thrombin generation, measured by endogenous thrombin potential and/or peak thrombin concentration. Secondary endpoints included recurrent VTE, arterial thrombosis, bleeding events, lipidomic profiles, and symptoms of post thrombotic syndrome. A total of 21 patients were enrolled (11 anticoagulation only and 10 anticoagulation and atorvastatin) over 3.5 years. Endogenous thrombin potential or peak thrombin was not significantly recued with the addition of atorvastatin. Atorvastatin did significantly reduce the mean LDLs at 3 months, without reduction of either d-dimer or high-sensitivity-C reactive protein. Given the low recruitment rate, continuation of the study was deemed futile and the study was terminated early. Barriers to enrollment and completion of study included the many ineligible patients by exclusion criteria (e.g., preexisting statin use, active malignancy, etc.) and high rate of lost follow-up. The pilot study was terminated early but could inform obstacles for future studies investigating the effects of statins in the management of patients with VTE.