Principles of Optimal Antithrombotic Therapy for Iliac VEnous Stenting (POATIVES): A national expert-based Delphi consensus study.

OBJECTIVE: Management of antithrombotic therapy in patients undergoing venous stents has not yet reached consensus, and there are not any recommendations from published guidelines. We undertook a Delphi consensus from Chinese experts to develop recommendations regarding the preferred antithrombotic therapy in patients following venous stenting. METHODS: The phase 1 questionnaire was comprised of three clinical scenarios of venous stenting for non-thrombotic iliac vein lesions (NIVL), acute deep vein thrombosis (DVT), and post-thrombotic syndrome (PTS) and was sent to venous practitioners across China. In phase 2, the results of phase 1 were distributed to a panel of experts for evaluation along with a questionnaire encompassing a series of statements produced during phase 1. A modified Delphi method was used to reach consensus on recommendations through two rounds of surveys. RESULTS: The phase 1 questionnaire was completed by 283 respondents. In phase 2, an expert panel consisting of 28 vascular surgeons and interventional radiologists was assembled and voted 17 statements relating to antithrombotic management after venous stenting for NIVL (4 statements), DVT (6 statements), and PTS (7 statements). The majority of the statements about the antithrombotic agent selection received a high consensus strength. CONCLUSIONS: Based on the national Delphi consensus of Chinese experts regarding antithrombotic therapy following iliac venous stenting in three common scenarios, most of the statements could be used to guide antithrombotic management following venous stenting. Further studies are required to clarify controversial issues including the dose and duration of anticoagulants, the role of antiplatelet agents, especially in patients with NIVL.

Meta-analysis of lytic catheter-based intervention for acute proximal deep vein thrombosis in the reduction of post-thrombotic syndrome.

OBJECTIVE: Post-thrombotic syndrome (PTS) is a common complication of deep vein thrombosis (DVT) that can result in significant morbidity for the patient with detrimental impact on their quality of life. Evidence supporting lytic catheter-based interventions (LCBI) undertaken for early thrombus reduction in acute proximal DVT for the prevention of PTS is conflicting. Despite this, rates of LCBIs are increasing. To summaries the existing evidence and pool treatment effects, a meta-analysis of randomized controlled trials assessing the efficacy of LCBIs in proximal acute DVT for the prevention of PTS was undertaken. METHODS: This meta-analysis was undertaken aligning with PRISMA guidelines following a protocol pre-registered on PROSPERO. Online searches of Medline and Embase databases, as well as the gray literature, were performed up to December 2022. Included articles were randomized controlled trials that studied the use of LCBIs with additional anticoagulation vs anticoagulation alone and had determined follow-up periods. Outcomes of interest were PTS development, moderate to severe PTS, major bleeding episodes, and quality-of-life measures. Subgroup analyses were performed for DVTs involving the iliac vein and/r common femoral vein. Meta-analysis was performed using a fixed effects model. Quality assessment was performed using the Cochrane Risk of Bias and GRADE assessment tools. RESULTS: Three trials were included in the final meta-analysis, the Post-thrombotic Syndrome after Catheter-directed Thrombolysis for Deep Vein Thrombosis (CaVenT), Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis (ATTRACT), and Ultrasound-accelerated Catheter-directed Thrombolysis Versus Anticoagulation for the Prevention of Post-thrombotic Syndrome (CAVA) trials, comprising 987 patients. Patients undergoing LCBIs had a reduced risk of PTS (relative risk [RR], 0.84; 95% confidence interval [CI], 0.74-0.95; P = .006) and a lower risk of developing moderate to severe PTS (RR, 0.75; 95% CI, 0.58-0.97; P = .03). LBCIs increased the risk of having a major bleed (RR, 2.03; 95% CI, 1.08-3.82; P = .03). In the iliofemoral DVT subgroup analysis, there was a trend toward decreasing the risk of developing PTS and moderate to severe PTS (P = .12 and P = .05, respectively). There was no significant difference in quality-of-life score (as measured by the Venous Insufficiency Epidemiological and Economic Study - Quality of Life/Symptoms) between the two groups (P = .51). CONCLUSIONS: Pooling of current best evidence suggests that LCBIs in acute proximal DVT decreases the rate of PTS and moderate to severe PTS with a number needed to treat of 12 and 18, respectively. However, this is complicated by a significantly higher rate of major bleeding with a number needed to treat of 37. This evidence supports the use of LCBIs in selected patients, including those who are at low risk of major bleeding.

Systematic Review and Meta-Analysis of the Pooled Rate of Post-Thrombotic Syndrome After Isolated Distal Deep Venous Thrombosis.

OBJECTIVE: To identify the rate of post-thrombotic syndrome (PTS) after isolated distal deep venous thrombosis (IDDVT) by performing a meta-analysis of the rate of PTS across randomised and observational studies. DATA SOURCES: MEDLINE, Embase, the Cochrane Controlled Trials Register, Clinicaltrials.gov, European Union Clinical Trials, International Standard Randomised Controlled Trial Number, and the Australian and New-Zealand Trials Registries. REVIEW METHODS: This review followed PRISMA guidelines using a registered protocol (CRD42021282136). Databases were searched up to December 2021 and prospective studies reporting the development of post-thrombotic syndrome were included; these were pooled with the meta-analysis. RESULTS: The results showed a post-thrombotic rate of 17% (95% CI 11 - 26%) (seven studies, 217 cases, 1 105 participants). Heterogeneity was high (I2 = 89%). On meta-regression, the rate of post-thrombotic syndrome was not correlated with the length of follow up (p = .71). Three studies (302 participants) reported the severity of post-thrombotic syndrome: 78% were mild (Villalta score 5 - 9); 11% were moderate (Villalta score 10 - 14), and 11% were severe (Villalta score ≥ 15). CONCLUSION: The risk of post-thrombotic syndrome after IDDVT was one in five and the risk of severe clinical manifestations, including ulceration, was one in 50. There was significant clinical, methodological, and statistical heterogeneity between studies and a substantial risk of bias from pooled studies. Randomised trials to support interventions for prevention of post-thrombotic syndrome are urgently needed.

Criteria to predict midterm outcome after stenting of chronic iliac vein obstructions (PROMISE trial).

BACKGROUND: Endovenous stent placement has become a first-line approach to prevent post-thrombotic syndrome in patients with chronic post-thrombotic obstruction (PTO) or nonthrombotic iliac vein lesions if conservative management fails. This study aims to identify factors associated with loss of patency to facilitate patient selection for endovenous stenting. METHODS: We retrospectively analyzed 108 consecutive patients after successful endovenous stenting for chronic vein obstruction performed at a single institution from January 2008 to July 2020. Using multivariable logistic regression, we explored potential predictive factors for loss of stent patency, including baseline demographics, post-thrombotic changes, and peak flow velocities measured in the common femoral vein (CFV), deep femoral vein, and femoral vein (FV) using duplex ultrasound examination. RESULTS: The mean follow-up duration was 41 ± 26 months, and participants had a mean age of 47.4 ± 15.4 years with 46.3% women. Ninety (83.3%) patients had PTO and 18 (16.7%) had nonthrombotic iliac vein lesions, predominantly due to May-Thurner syndrome. Loss of patency occurred in 20 (18.5%) patients, all treated for PTO. Comorbidities, side of intervention, and sex did not differ between patients with occluded and patent stents. Stent occlusion was more common with increasing number of stents implanted (P < .001) and with distal stent extension into and beyond the CFV (P < .001). Preinterventional predictive factors for stent occlusion were lower duplex ultrasound peak velocity in the CFV (odds ratio [OR]: 7.52, 95% confidence interval [CI]: 2.54-22.28; P < .001) and FV (OR: 10.75, 95% CI: 2.07-55.82; P < .005), and post-thrombotic changes in the deep femoral vein (OR: 4.51, 95% CI: 1.53-13.25; P = .006) and FV (OR: 3.62: 95% CI: 1.11-11.84; P = .033). Peak velocities of ≤7 cm/s (interquartile range: 0-20 cm/s) in the CVF and ≤8 cm/s (interquartile range: 5-10 cm/s) in the FV were significantly associated with loss of patency. CONCLUSIONS: Insufficient venous inflow as assessed by low peak velocities in the CFV and FV as well as post-thrombotic findings represent reliable risk predictors for stent occlusions, warranting their inclusion into the decision-making process for invasive treatment of PTO.

Restoring Venous Patency with the ClotTriever Following Deep Vein Thrombosis.

BACKGROUND: Although randomized data remain inconclusive, invasive endovenous therapy is increasingly favored in patients with extensive iliocaval or iliofemoral deep vein thrombosis (DVT) to reduce the rates of postthrombotic syndrome. Previously, pharmacomechanical thrombectomy was the therapy of choice, but the Inari ClotTriever device is an appealing, purely mechanical, alternative. It may reduce bleeding risk, intensive care unit admission, and the need for multiple procedures when compared with traditional thrombolysis. We present a series of 18 patients treated with the ClotTriever for extensive iliocaval or iliofemoral DVT. METHODS: The Inari ClotTriever is a percutaneous mechanical thrombectomy system consisting of an expandable nitinol collection bag that is dragged along the vein wall, separating and capturing thrombus for collection into the retrieval sheath. We retrospectively reviewed all patients undergoing ClotTriever thrombectomy since the device became available at our quaternary referral center in June 2019. The review of these patients' records was determined to be exempt by our institutional review board. RESULTS: Eighteen patients underwent ClotTriever thrombectomy between June 2019 and November 2021. Most patients (N = 16, 89%) presented within 2 weeks of symptom onset, and identifiable provoking factors were present in all patients. The most common provoking factor was anatomy, with May-Thurner syndrome present in 8 patients. All patients had restoration of unimpeded venous flow in the treated segments, although 3 had some residual nonflow limiting thrombus. There were no bleeding events or repeat venous procedures. The median postprocedure length of stay of 2 days. Postoperative venous imaging was performed in 15 patients and showed patency of the treated segment in 14 patients. Revised Clinical Venous Severity Scores were available in 14 patients during the course of follow-up. Of these, 9 patients' highest scores were 0, 2 patients' highest scores were 2, 2 patients' highest scores were 4, and 1 patient had a high score of 8. CONCLUSIONS: Venous flow was re-established in all 18 patients treated with the ClotTriever in this series, with no bleeding complications, and median postprocedure length of stay of 2 days. All patients with available follow-up, except 1, retained patency of the treated venous segments, and most had mild postthrombotic syndrome or none at all. These findings suggest that the ClotTriever is a safe and effective way to treat extensive iliocaval/femoral DVT.

Treatment Strategies for Proximal Deep Vein Thrombosis: A Network Meta-analysis of Randomised Controlled Trials.

OBJECTIVE: To investigate the outcomes of treatment strategies for proximal and iliofemoral deep vein thrombosis (DVT). METHODS: Randomised controlled trials (RCTs) investigating outcomes of catheter directed thrombolysis (CDT), ultrasound assisted CDT (USCDT), percutaneous aspiration thrombectomy (PAT), and best medical therapy (BMT) for proximal DVT from 2000 onwards were considered. MEDLINE, EMBASE, and CINAHL were searched using the Healthcare Databases Advanced Search interface developed by the National Institute for Health and Care Excellence. The primary outcome was the rate of post-thrombotic syndrome (PTS), which was defined using the Villalta scoring system (score of ≥5). Secondary outcomes included vessel patency, recurrence, bleeding, and mortality. The network of evidence was summarised using network plots, and random effects network meta-analyses were performed. The certainty of evidence was assessed using the Certainty In Network Meta-Analysis (CINeMA) approach. RESULTS: Seven RCTs meeting the inclusion criteria were identified. There were direct comparisons between medical therapy, CDT, and USCDT across outcomes, except for patency. There were no direct comparisons between medical therapy and PAT (except for patency), and USCDT and PAT. There was no significant difference observed in PTS between the treatment modalities for proximal and iliofemoral DVT (low certainty). There was a significant difference in patency rates between medical therapy and USCDT (odds ratio [OR] 9.46, 95% confidence interval [CI] 3.05 - 29.35; low certainty) and CDT (OR 2.03, 95% CI 1.46 - 2.80; low certainty) in favour of USCDT and CDT, respectively, for proximal DVT. USCDT significantly improved patency rates compared with CDT (OR 4.67, 95% CI 1.58 - 13.81; very low certainty) for proximal DVT. There was no significant difference in DVT recurrence, bleeding, or mortality between treatment groups for proximal and iliofemoral DVT (low to moderate certainty for most comparisons). CONCLUSION: USCDT may improve patency rates compared with BMT and the other interventional treatment modalities used for the management of proximal DVT. However, no treatment modality showed superiority with regard to a reduction in PTS, and overall, the quality of available evidence is poor.

Elastic compression stockings to prevent post-thrombotic syndrome in proximal deep venous thrombosis patients without thrombus removal.

OBJECTIVE: To evaluate the effectiveness of elastic compression stockings (ECS) in prevention of post-thrombotic syndrome (PTS) in patients suffering from proximal deep venous thrombosis (DVT) who did not undergo thrombus removal procedures. METHODS: In this randomized trial, patients with Iliofemoral venous thrombosis (IFDVT) and femoral-popliteal venous thrombosis who had not undergone thrombus removal procedures were screened at a single medical institution between December 2016 and June 2018. These patients were randomly assigned as an ECS group (wear ECS) and control group (not wear ECS). The primary end point was the incidence of PTS based on the Villalta scale at 24 months. The secondary end points included patient quality of life and symptom severity based on the VEINES-QoL/Sym questionnaire. Recurrent DVT in the same limb, compliance with ECS use, and other adverse events were also recorded. A logistic regression analysis was also performed to determine risk factors of PTS. RESULTS: Two hundred thirty-two patients were included in this study. One hundred thirteen patients were in the ECS group and 119 in the control group. The incidence of PTS was 42.0% in the ECS group and 57.8% in the control group at 24 months (risk ratio [RR], 0.726; 95% confidence interval [CI] 0.547-0.964; P = .024). The VEINES-QoL score was 63.7 ± 4.6 in the ECS group, which was higher than in the control group (60.6 ± 6.9; P < .001). Moreover, the VEINES-Sym scores revealed that patients in the ECS group reported better symptom relief than those in the control group (45.8 ± 5.1 vs 43.8 ± 6.1; P = .014). According to Logistic regression analysis of the entire cohort, IFDVT was a risk factor for PTS (RR, 2.253; 95% CI, 1.136-4.468) and high compliance with the use of ECS was protect factor (RR, 0.516; 95% CI, 0.277-0.961). CONCLUSIONS: These results suggest that ECS can prevent PTS in patients with IFDVT and femoral popliteal venous thrombosis who do not undergo thrombus removal procedures.

A risk score for iliofemoral patients with deep vein thrombosis.

OBJECTIVE: Deep vein thrombosis (DVT) is a common condition with a high risk of post-thrombotic morbidity, especially in patients with a proximal thrombus. Successful iliofemoral clot removal has been shown to decrease the severity of post-thrombotic syndrome. It is assumed that earlier thrombus lysis is associated with a better outcome. Generally, the earlier IFDVT is confirmed, the earlier thrombus lysis could be performed. d-Dimer levels and Wells score are currently used to assess the preduplex probability for DVT; however, some studies indicate that the d-dimer value varies depending on the thrombus extent and localization. Using d-dimer and other risk factors might facilitate development of a model selecting those with an increased risk of IFDVT that might benefit from early referral for additional analysis and adjunctive iliofemoral thrombectomy. METHODS: All consecutive adult patients from a retrospective cohort of STAR diagnostic center (primary care) in Rotterdam suspected of having DVT between September 2004 and August 2016 were assessed for this retrospective study. The diagnostic workup for DVT including Wells score and d-dimer were performed as well as complete duplex ultrasound examination. Patients with objective evidence of DVT were categorized according to thrombus localization using the Lower Extremity Thrombolysis classification. Logistic regression analysis was done for a model predicting IFDVT. The cut-off value of the model was determined using a receiver operating characteristic curve. RESULTS: A total of 3381 patients were eligible for study recruitment, of whom 489 (14.5%) had confirmed DVT. We developed a multivariate model (sensitivity of 77% and specificity of 82%; area under the curve, 0.90; 0.86-0.93) based on d-dimer, Wells score, age, and anticoagulation use, which is able to distinguish IFDVT patients from all patients suspected of DVT. CONCLUSIONS: This multivariate model adequately distinguishes IFDVT among all suspected DVT patients. Practically, this model could give each patient a preduplex risk score, which could be used to prioritize suspected IFDVT patients for an immediate imaging test to confirm or exclude IFDVT. Further validation studies are needed to confirm potential of this prediction model for IFDVT.

Pharmacomechanical catheter-directed thrombolysis for acute iliofemoral deep vein thrombosis in a large study population.

BACKGROUND: We have analyzed our single-center immediate and follow-up results in the management of acute iliofemoral deep vein thrombosis (IFDVT) using pharmacomechanical catheter-directed thrombolysis (PMCDT) to determine the safety, accuracy, and effects on quality of life and whether this treatment strategy prevents post-thrombotic syndrome (PTS). METHODS: The cases of 230 patients who had undergone PMCDT to treat IFDVT from January 2017 to December 2018 were retrospectively reviewed. The preoperative, operative, and postoperative variables, Marder scores, outcomes, and follow-up assessments with the Villalta score and venous clinical severity score were investigated. RESULTS: Anatomic success was achieved for 95.2% of the 230 patients. The mean Marder score had decreased from 12.65 ± 2.1 to 2.4 ± 1.3 postoperatively (P < .01). Early recurrent thrombosis had developed in 13 patients (5.65%). The primary patency at the 1-, 6-, and 12-month follow-up visits was 94.0%, 87.2%, and 81.7%, respectively. From 1 to 6 months, the Villalta score had decreased from 8.32 ± 4.14 to 3.43 ± 0.61 and the venous clinical severity score had decreased from 4.0 ± 1.8 to 1.82 ± 0.36 (P < .05). No statistically significant difference was found in the PTS severity scores at 12 months of follow-up compared with at 6 months. The mean change in the venous disease-specific quality of life from baseline to 12 months was 29.41 ± 1.99 (P = .029). The total recurrence rate was 19.63% at 1 year. CONCLUSIONS: For a select group of patients with acute IFDVT, the use of PMCDT and postoperative anticoagulation therapy offered significant reductions in clot burden, leg pain, and swelling, achieving a significant reduction in PTS severity scores at 6 months.

Efficacy of rivaroxaban in prevention of post-thrombotic syndrome: A systematic review and meta-analysis.

OBJECTIVE: Direct oral anticoagulants (DOACs) have been recommended for the treatment of deep vein thrombosis (DVT). However, the benefits are uncertain for the prevention of post-thrombotic syndrome (PTS). We performed a systematic review and meta-analysis of reported studies to assess the efficacy of DOACs vs vitamin K antagonists for the risk reduction of PTS in patients with DVT. METHODS: We searched PubMed, Medline, the Cochrane Library, Embase, and the Web of Science for studies reporting on the development of PTS after acute DVT. The outcomes were the risk reduction of PTS, PTS severity, the presence of residual vein thrombosis, and the incidence of recurrent venous thromboembolic (VTE) events. RESULTS: A total of 59,199 patients from six retrospective and two randomized controlled studies had received DOAC treatment and were followed up for the development of PTS. In all studies, rivaroxaban had been compared with initial low-molecular-weight heparin followed by warfarin. Of the 59,199 patients, 19,840 (33.5%) had received rivaroxaban and 39,377 (66.5%), warfarin. The rivaroxaban group had a significant reduction in PTS development compared with the warfarin group (odds ratio [OR], 0.52; 95% confidence interval [CI], 0.43-0.63; P < .001). Severe PTS was less common in the rivaroxaban group than in the warfarin group (3.7% vs 6.4%; OR, 0.55; 95% CI, 0.36-0.85; P = .024). Additionally, rivaroxaban was associated with a significant reduction in VTE recurrence (OR, 0.83; 95% CI, 0.59-1.18; P = .03) and low rates of residual vein thrombosis compared with warfarin (36.5% vs 51.8%; P = .037). CONCLUSIONS: Rivaroxaban after acute DVT was associated with a reduced risk of PTS compared with warfarin. Patients treated with rivaroxaban more rarely developed severe PTS and recurrent VTE events compared with patients treated with warfarin.

Comparison of Pharmacomechanical Catheter-Directed Thrombolysis versus Catheter-Directed Thrombolysis for the Treatment of Acute Iliofemoral Deep Vein Thrombosis: Measures of Long-Term Clinical Outcome and Quality of Life.

BACKGROUND: We studied the occurrence of post-thrombotic syndrome (PTS) in patients with either Pharmacomechanical Catheter-Directed Thrombolysis (hereafter "pharmacomechanical thrombolysis"; PT) or Catheter-Directed Thrombolysis (CDT) for the treatment of acute iliofemoral deep vein thrombosis (DVT). METHODS: This retrospective study of data archived between September 2013 and September 2015 was surveyed. Two separate patient populations were identified and analyzed: patients were separated into PT group or CDT group. For up to 5 years post-treatment, the incidence, severity of PTS, and chronic venous insufficiency questionnaire (CIVIQ) score difference were compared. RESULTS: The study identified 131 patients divided into PT group (65) and CDT group (66). Within the 5-year follow-up period, there was no significant difference in the incidence of PTS (45.0% PT vs. 57.6% CDT; odds ratio (OR) = 0.602; 95% confidence interval (CI), 0.291-1.242; P = 0.201), but there was reduced severe PTS in the PT group (Villalta scale ≥15 or ulcer:11.7% PT vs. 27.1% CDT; OR 0.355; 95%CI 0.134-0.941, P = 0.039; and Venous Clinical Severity Score (VCSS) ≥8: 13.3%PT vs. 28.8% CDT; OR 0.380; 95% CI 0.149-0.967, P = 0.045). There was also a larger improvement of venous disease-specific quality of life (QOL) in the PT group at 5 years [(62.89 ± 14.19) vs (56.39 ±15.62), P = 0.036] compared to the CDT group. CONCLUSION: In patients with acute iliofemoral DVT treated with PT, PT significantly reduced PTS severity scores, and resulted in greater improvement in venous disease-specific QOL. However, the incidence of was not significantly different from that measured in the CDT.

Effect of statins on development of post thrombotic syndrome: cohort study. / Efecto de las estatinas en el desarrollo de síndrome postrombótico: estudio de cohorte

Objetivo: Explorar la asociación entre consumo de estatinas (CE) y desarrollo de síndrome postrombótico (SPT). Método: Cohorte retrospectiva con pacientes con primer episodio de trombosis venosa profunda (TVP) entre el 06/2006 y el 12/2017, incluidos en el Registro Institucional de Enfermedad TromboEmbólica (RIET) del Hospital Italiano de Buenos Aires. Se consideró exposición al CE entre los 30 días previos y hasta 180 días posterior al diagnóstico de TVP. Se definió SPT según constaba este dato en la base de seguimiento del RIET. Se evaluó el desarrollo de SPT con un modelo de riesgos proporcionales de Cox, reportando hazard ratios (HR) crudas y ajustadas. Se consideró la confusión por indicación del CE y se utilizó un propensity score (PS) para el ajuste del riesgo estimado, reportando los HR con sus intervalos de confianza del 95% (IC 95%). Resultados: Se incluyeron 905 pacientes, de los cuales 273 fueron CE y 632 no consumidor de estatinas (NCE). Al seguimiento, la incidencia de SPT fue: 6.59% (18) en el grupo CE y 8.07% (51) en el grupo NCE, con p = 0.412. La razón de riesgo para el desarrollo de SPT de CE resultó no significativa (HR cruda: 0.78; IC 95%: 0.43-1.41; p = 0.414). La HR de CE ajustada por edad, sexo, antiinflamatorios no esteroideos, corticosteroides, inmovilidad, anticoagulante, hipertensión arterial, diabetes, dislipidemia, insuficiencia renal crónica, enfermedad coronaria, accidente cerebrovascular, insuficiencia cardiaca y enfermedad oncológica fue 0.45 (IC 95%: 0.13-1.5; p = 0.196). La HR del CE ajustado por edad, sexo, antiinflamatorios no esteroideos, corticosteroides, inmovilidad, tratamiento anticoagulante, enfermedad oncológica y PS fue de 0.52 (IC 95%: 0.17-1.66; p = 0.272). Conclusiones: El CE no se asoció con menor SPT, aunque hubo escaso número de eventos detectados. Objective: To evaluate the association between statin consumption and development of post-thrombotic syndrome (PTS). Methods: Retrospective cohort study which included patients with a first episode of deep vein thrombosis (DVT) between 06/2006 and 12/2017, included in the Institutional Registry of ThromboEmbolic Disease of the Italian Hospital of Buenos Aires, Argentina. Exposure to statin use (SU) was considered between the 30 days before and up to 180 days after the diagnosis of DVT. PTS was defined as recorded dataset on registry. The development of PTS was evaluated with Cox proportional hazards model, raw and adjusted hazard ratios (HR) were reported. Confusion was considered by indication of SU and a propensity score (PS) was used for adjustment. We reported HR with their 95% confidence interval (CI); p value < 0.05 was considered statistically significant. Results: Of 1393 patients, 905 were included for the analysis, of which 273 were SU and 632 non-statin users (NSU). At follow-up, incidence of PTS was: 6.59% (18) in the SU group and 8.07% (51) in the NSU group, with p = 0.412. Crude HR for PTS for SU was not significant (0.78; 95% CI: 0.43-1.41; p = 0.414). Adjusted HR of SU by age, sex, non-steroidal anti-inflammatory drugs, corticosteroids, immobility, anticoagulant, high blood pressure, diabetes, dyslipidemia, chronic renal failure, coronary heart disease, stroke, heart failure and cancer disease was 0.45 (95% CI: 0.13-1.5; p = 0.196) for PTS. While HR for the development of PTS adjusted by age, sex, non-steroidal anti-inflammatory drugs, corticosteroids, immobility, anticoagulant treatment, cancer disease and PS of the SU was 0.52 (95% CI: 0.17-1.66; p = 0.272). Conclusion: No statistically significant association was found between CE and the development of SPT, although there were a small number of events detected in both groups.

Efecto de las estatinas en el desarrollo de síndrome postrombótico: estudio de cohorte / Effect of statins on development of post thrombotic syndrome: cohort study

Resumen Objetivo: Explorar la asociación entre consumo de estatinas (CE) y desarrollo de síndrome postrombótico (SPT). Método: Cohorte retrospectiva con pacientes con primer episodio de trombosis venosa profunda (TVP) entre el 06/2006 y el 12/2017, incluidos en el Registro Institucional de Enfermedad TromboEmbólica (RIET) del Hospital Italiano de Buenos Aires. Se consideró exposición al CE entre los 30 días previos y hasta 180 días posterior al diagnóstico de TVP. Se definió SPT según constaba este dato en la base de seguimiento del RIET. Se evaluó el desarrollo de SPT con un modelo de riesgos proporcionales de Cox, reportando hazard ratios (HR) crudas y ajustadas. Se consideró la confusión por indicación del CE y se utilizó un propensity score (PS) para el ajuste del riesgo estimado, reportando los HR con sus intervalos de confianza del 95% (IC 95%). Resultados: Se incluyeron 905 pacientes, de los cuales 273 fueron CE y 632 no consumidor de estatinas (NCE). Al seguimiento, la incidencia de SPT fue: 6.59% (18) en el grupo CE y 8.07% (51) en el grupo NCE, con p = 0.412. La razón de riesgo para el desarrollo de SPT de CE resultó no significativa (HR cruda: 0.78; IC 95%: 0.43-1.41; p = 0.414). La HR de CE ajustada por edad, sexo, antiinflamatorios no esteroideos, corticosteroides, inmovilidad, anticoagulante, hipertensión arterial, diabetes, dislipidemia, insuficiencia renal crónica, enfermedad coronaria, accidente cerebrovascular, insuficiencia cardiaca y enfermedad oncológica fue 0.45 (IC 95%: 0.13-1.5; p = 0.196). La HR del CE ajustado por edad, sexo, antiinflamatorios no esteroideos, corticosteroides, inmovilidad, tratamiento anticoagulante, enfermedad oncológica y PS fue de 0.52 (IC 95%: 0.17-1.66; p = 0.272). Conclusiones: El CE no se asoció con menor SPT, aunque hubo escaso número de eventos detectados.

Abstract Objective: To evaluate the association between statin consumption and development of post-thrombotic syndrome (PTS). Methods: Retrospective cohort study which included patients with a first episode of deep vein thrombosis (DVT) between 06/2006 and 12/2017, included in the Institutional Registry of ThromboEmbolic Disease of the Italian Hospital of Buenos Aires, Argentina. Exposure to statin use (SU) was considered between the 30 days before and up to 180 days after the diagnosis of DVT. PTS was defined as recorded dataset on registry. The development of PTS was evaluated with Cox proportional hazards model, raw and adjusted hazard ratios (HR) were reported. Confusion was considered by indication of SU and a propensity score (PS) was used for adjustment. We reported HR with their 95% confidence interval (CI); p value < 0.05 was considered statistically significant. Results: Of 1393 patients, 905 were included for the analysis, of which 273 were SU and 632 non-statin users (NSU). At follow-up, incidence of PTS was: 6.59% (18) in the SU group and 8.07% (51) in the NSU group, with p = 0.412. Crude HR for PTS for SU was not significant (0.78; 95% CI: 0.43-1.41; p = 0.414). Adjusted HR of SU by age, sex, non-steroidal anti-inflammatory drugs, corticosteroids, immobility, anticoagulant, high blood pressure, diabetes, dyslipidemia, chronic renal failure, coronary heart disease, stroke, heart failure and cancer disease was 0.45 (95% CI: 0.13-1.5; p = 0.196) for PTS. While HR for the development of PTS adjusted by age, sex, non-steroidal anti-inflammatory drugs, corticosteroids, immobility, anticoagulant treatment, cancer disease and PS of the SU was 0.52 (95% CI: 0.17-1.66; p = 0.272). Conclusion: No statistically significant association was found between CE and the development of SPT, although there were a small number of events detected in both groups.

The good, bad and the ugly of the Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis trial from the viewpoint of clinicians.

OBJECTIVE: Acute deep venous thrombosis (DVT) can be complicated by post-thrombotic syndrome, which is associated with significant morbidity and healthcare costs. The Acute Venous Thrombosis: Thrombus Removal with Adjunctive Catheter-Directed Thrombolysis (ATTRACT) was the largest and most controversial randomized controlled trial evaluating the use of pharmacomechanical catheter-directed thrombolysis (CDT) for the prevention of post-thrombotic syndrome after acute DVT. This study aimed to evaluate clinicians' opinion on the ATTRACT trial and its impact on clinical practice. METHODS: An online survey consisting of 10 core multiple choice items and a maximum of five follow-up open-ended questions was delivered to vascular surgeons, interventional radiologists, hematologists, and interventional cardiologists affiliated with 10 international societies between April 23 and July 1, 2019. Clinicians' views on the main limitations of the ATTRACT trial, its impact on patient selection for thrombolysis and the need for a new trial were evaluated. RESULTS: Out of 15,650 contacted clinicians, 451 (3%) completed the survey, with 74% vascular surgeons, 24% interventional radiologists, 2% hematologists, and 0.2% interventional cardiologists. The majority of respondents (79%) were aware of the results of the ATTRACT trial before completing the survey and routinely performed pharmacomechanical CDT (PCDT) in their centers (70%). Only 20% of clinicians considered ATTRACT to be a well-designed and well-performed trial. The inclusion of femoropopliteal DVT was reported as the main limitation of the trial by 55% of respondents. Despite half of the participating clinicians reporting no change in their clinical practice, equal number of clinicians (14%) were encouraged and discouraged from treating iliofemoral DVT. More than one-half of the respondents thought that the use of PCDT would be defensible in a court of law despite the increased risk of bleeding reported in the study. Nearly two-thirds of participating clinicians recommended performing a trial limited to iliofemoral DVT, with a follow-up period of 5 years, quality of life as the primary outcome measure, and standardization of thrombolysis protocol across the trial sites. CONCLUSIONS: ATTRACT failed to provide the long-awaited indisputable evidence on the use of PCDT. Surveyed clinicians were aware of the limitations of this trial and the need for further evidence on the subject.

The management and referral of iliofemoral deep venous thrombosis in North West London.

BACKGROUND: Post-thrombotic syndrome is a common complication of iliofemoral deep venous thrombosis (IFDVT). Existing evidence and National Institute for Health and Care Excellence guidelines suggest that this can be reduced by prompt thrombolytic therapy or thrombectomy. We aimed to evaluate the characteristics of IFDVT patients and to identify whether patients are being offered the recommended treatment pathway. METHODS: A multicenter cross-sectional study was conducted across eight hospital sites in the North West London region, of which two were hub hospitals in their local vascular service networks. Patients with proximal DVT were identified using International Classification of Diseases, Tenth Revision coding during a 1-year period. Data on demographics, diagnostic methods used, interventions, and referrals were extracted from electronic and paper medical records. RESULTS: During the study period, 132 patients with IFDVT were identified (mean age, 59.4 years; 55% female); 75% of these patients had an IFDVT. In this cohort, the biggest predisposing factors were previous DVT (n = 35), malignant disease (n = 35), and immobility (n = 20). In total, 104 patients were administered anticoagulation, and 88 of these patients received anticoagulation within 24 hours. The cases of 45 patients were either discussed with or promptly referred to a vascular service, after which 20 patients were treated solely with anticoagulation, whereas 20 patients received thrombolysis of varying methods. CONCLUSIONS: A significant proportion (56%) of symptomatic IFDVT patients are not being appropriately referred to or discussed with vascular services. Of these, 43% would have been eligible for consideration of early thrombus removal. Adherence to the National Institute for Health and Care Excellence guidelines could be improved by increasing awareness among emergency department colleagues.

Risk and protective factors for post-thrombotic syndrome after deep venous thrombosis.

OBJECTIVE: The most frequent complication of deep venous thrombosis (DVT) is post-thrombotic syndrome (PTS). We recently showed inhibition of varicose vein development by atorvastatin and rosuvastatin. The aim of this study was to test the influence of lipid-lowering therapy with statins on PTS development. METHODS: All patients between January 2002 and June 2018 with diagnosed DVT were enrolled in this study and analyzed retrospectively. Documentation was performed using the standardized system M1 (CompuGroup Medical, Koblenz, Germany) throughout the observation period. Patients received therapeutic anticoagulation and compression stockings. In case of recurrent DVT, patients received lifelong therapeutic anticoagulation. All patients received clinical examination and duplex ultrasound evaluation 3 to 6 months after primary diagnosis and annually thereafter. RESULTS: A total of 579 patients with DVT were enrolled in this study. Of these patients, 414 (71%) developed PTS (337/414 [81%] presented with the mild version; mean Villalta score, 5.79). Risk factors for PTS development were recurrent DVT (P = .001) and malignant disease (P = .001). Protective factors were therapy with platelet aggregation inhibitors (P = .049) and lipid-lowering therapy with statins (P = .001). After multivariable analysis, the only risk factor was recurrent DVT (P = .001), and the only protective factor was lipid-lowering therapy (P = .001). CONCLUSIONS: Post-thrombotic changes might be reduced by lipid-lowering therapy.

Percutaneous mechanical thrombectomy in the treatment of acute iliofemoral deep vein thrombosis: a systematic review.

BACKGROUND: Conventional treatment of deep vein thrombosis (DVT) of the lower extremities by anticoagulation alone has been proven to be insufficient to prevent recurrence and post-thrombotic syndrome (PTS). Early restoration of venous patency and preservation of valvular function by endovascular surgery has been advocated. The aim of this study was to review the efficacy and safety of percutaneous mechanical thrombectomy (PMT) against catheter-directed thrombolysis (CDT) in the treatment of acute iliofemoral DVT. METHODS: Three hundred sixty-nine articles were identified through screening of the PubMed, EMBASE, and Cochrane databases from January 2006 to December 2016. RESULTS: Fifteen retrospective studies and one prospective registry, totalling 1170 patients, were recruited for qualitative synthesis. The venous patency rate ranged from 75% to 100% with mean follow-up of 12.3 months. The rates of PTS and recurrent DVT were less than 17% and 15%, respectively. The overall mortality rate was 0.26%. Compared with CDT, PMT was shown to reduce PTS at 1 year (Villalta score: 2.1 ± 3.0 in the PMT group and 5.1 ± 4.1 in the CDT group, P=0.03) and bleeding complications (packed cells transfused: 0.2 ± 0.3 units in the pharmacomechanical thrombectomy group and 1.2 ± 0.7 units in the CDT group, P<0.05). CONCLUSION: Percutaneous mechanical thrombectomy is a safe and effective treatment for acute iliofemoral DVT in terms of restoration of venous patency, prevention of DVT recurrence, and PTS. Compared with CDT alone, PMT offers a lower risk of PTS and bleeding complications.

Treatments to prevent primary venous ulceration after deep venous thrombosis.

OBJECTIVE: This systematic review and meta-analysis aimed to assess whether compression stockings or other interventions reduce the incidence of venous ulceration after acute deep venous thrombosis. METHODS: We searched PubMed and Embase for randomized controlled trials (RCTs), restricted to English, Spanish, and Hebrew, related to post-thrombotic syndrome and venous ulceration in participants with confirmed deep venous thrombosis. Our primary statistical assessment was the Peto odds ratio (OR). RESULTS: Our search generated 23 RCTs meeting inclusion and exclusion criteria, summing 6162 patients and 146 ulcerative events. Trials were categorized into compression, low-molecular-weight heparin (LMWH), procedural thrombolysis, medical thrombolysis, or miscellaneous. Six compression trials were identified, of which five were included in meta-analysis. Compression compared with placebo did not reduce venous ulceration (OR, 0.915; 95% confidence interval [CI], 0.475-1.765), and long-term compression was not superior to short-term compression (OR, 1.36; 95% CI, 0.014-1.31). Four LMWH trials were identified but were not subjected to meta-analysis because of intertrial heterogeneity. One trial, comparing extended tinzaparin with warfarin, demonstrated eight ulcers in the warfarin group and one ulcer in the LMWH group (relative risk, 0.125; P < .05). Three procedural thrombolysis trials were pooled into meta-analysis; fewer ulcerative events occurred in procedural thrombolysis patients, but the effect was not significant (OR, 0.677; 95% CI, 0.338-1.358). Eight medical thrombolysis trials were identified. Pooled analysis of five trials demonstrated a protective effect on ulceration in streptokinase patients vs standard heparinization (OR, 0.125; 95% CI, 0.021-0.739). However, these trials were of poor-quality study design, had small sample size, and had poor overall outcomes. Miscellaneous studies included a trial of hidrosmina, a vasoactive flavonoid, and a trial comparing 6-month warfarin treatment with 6 weeks; neither trial had significant outcomes. Intertrial heterogeneity was not adequately assessed with the I2 value as venous ulceration is a rare event; the Grading of Recommendations Assessment, Development, and Evaluation evidence for most trials was very low, with the exception of procedural thrombolysis trials, for which it was low. CONCLUSIONS: We found insufficient evidence to assess whether compression or other interventions protect against venous ulceration. To develop guidelines for treatment decisions related to prevention of venous ulceration, high-powered RCTs investigating venous leg ulcers as a primary outcome are required.