Femoropopliteal Deep Venous Thrombosis Research Articles

The Importance of Early Thrombus Removal

Historically, anticoagulation has been the primary treatment for acute lower extremity deep venous thrombosis (DVT) with or without thrombolysis. Despite large amounts of clinical research data supporting an ‘open vein hypothesis’, which favours early thrombus removal, clinicians have been hesitant to take this option due to a historically high risk of major bleeding and a few notable studies that failed to show any meaningful benefit. The ATTRACT trial failed to show the benefit of using pharmacomechanical catheter-directed thrombolysis (PCDT) for iliofemoral and femoropopliteal DVT but did result in more bleeding. However, the CaVent study before it revealed a significant reduction in post-thrombotic syndrome (PTS) for patients with iliofemoral and femoral DVT after long-term follow-up past 24 months that grew over time. Since these trials, there have been significant advancements in magnetic resonance and CT venography, intravascular ultrasound (IVUS), venous stenting and thrombectomy catheters meaning there is little to no need for adjunct thrombolytics. Results from ongoing research such as CLEAR-DVT reflect the advances in modern technology.

Outcomes of the treatment of contralateral iliac venous thrombosis after stenting across the iliocaval confluence

Among the complications related to the endovascular treatment of the left common iliac vein obstruction, the contralateral deep venous thrombosis consists in a late complication of the procedure. This case series describes the endovascular treatment of four patients with right iliofemoral deep venous thrombosis caused by jailing of the inferior vena cava confluence, due to previous stents implanted in the left common iliac vein. All the four patients were admitted with pain and swelling of the right lower limb, and one patient presented with phlegmasia cerúlea dolens. The patients were evaluated with duplex-scan and angioCT-Scan that confirmed extensive right iliofemoral and femoropopliteal deep venous thrombosis, except for one patient, whose DVT propagated to superficial femoral vein, without popliteal involvement. All patients were submitted to endovascular treatment with pharmacomechanical thrombectomy, previous stent recanalization and stent deployment in the iliocaval confluency. Regarding the post-operative complications, one patient presented with hemoglobinury, which evolved with anuria, and in the first day post-operative with acute kidney failure and necessity of hemodialysis for 8 days, after that evolved with total renal function recovery. During the hemodialysis period, this patient received non-fractioned heparin, instead of enoxaparin. All patients presented with satisfactory improvement on limb edema, in the first day and thereafter in the first week post-operative. The pharmacomechanical thrombectomy technique followed by angioplasty and kissing stenting was a safe and efficient procedure in this case series report.

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

ObjectiveAcute 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. MethodsAn 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. ResultsOut 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. ConclusionsATTRACT 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.

Initial experience with a new pharmacomechanical thrombectomy device for deep venous thrombosis: Report of 91 cases.

Background To evaluate the efficacy and safety of pharmacomechanical thrombectomy using a new rotational thrombectomy device with additional thrombus-removal methods for deep venous thrombosis. Methods A total of 91 patients admitted to our tertiary center with symptomatic iliac, ilio-femoral, femoro-popliteal deep venous thrombosis and who underwent hybrid pharmacomechanical thrombectomy constituted the study group. Postinterventional color Doppler ultrasonography was repeated at 1st, 6th, and 12th months. Villalta scoring system was used to evaluate the patients for the development of post-thrombotic syndrome after deep venous thrombosis. The patient-reported severity of pain in the index leg was measured on a Likert scale. Results Of the 91 patients whose charts were reviewed, the location of thrombus was iliofemoral in 60 (65.9%) and femoropopliteal in 31 (34.1%) patients, respectively. Duration of symptoms was 5.62 ± 3.43 (range, 2–15) days. Technical success was observed in 82 patients (90.1%) at 3 months, in 77 patients (84.6%) at 6 months, and in 74 patients (81.3%) at 12 months. Villalta score was over 10 points in 15 of 17 patients whose Doppler US revealed venous occlusions, at 12 months, and in 8 patients with recurrent deep venous thrombosis. Post-thrombotic syndrome was detected in 18 patients in our study. Twelve (13.2%) of these 18 patients had mild, 5 (5.5%) moderate, and 1 (1.1%) severe PTS. In predicting predisposing factors in 18 patients with PTS, 13 patients (72.2%) had a Villalta score ≥10, 10 patients (55.6%) had experienced a delayed endovascular procedure (≥10 days), and 8 patients (44.4%) had recurrent deep venous thrombosis. Conclusion The endovenous pharmacomechanical thrombectomy with the Mantis thrombectomy device in the treatment of acute and subacute iliofemoral deep venous thrombosis is a promising approach in terms of efficacy and safety in the early period regarding reasonable and long-term prevention of post-thrombotic syndrome, development of pulmonary thromboembolism, and adequate venous system patency.

Analysis of 1338 Patients with Acute Lower Limb Deep Venous Thrombosis (DVT) Supports the Inadequacy of the Term “Proximal DVT”

For decades acute lower limb deep venous thrombosis (DVT) has been subdivided into distal DVT (isolated to the calf veins) and proximal DVT (extending above calf vein level). The aim of this study was to analyse the anatomical site and extent of thrombus in a large cohort of patients with acute DVT. A retrospective analysis of all patients aged >18 years, presenting with unilateral DVT according to duplex ultrasound investigation was performed at the University Hospital of Antwerp, Belgium (1994-2012). The anatomical site and extent of thrombus was registered and subdivided into five segments: calf veins (segment 1), popliteal vein (segment 2), femoral vein (segment 3), common femoral vein (segment 4), and iliac veins, with or without inferior vena cava (segment 5). The median age of the 1,338 patients (50% male) included was 62 years (range 18-98 years). Left sided DVT was predominant (57%). DVT was limited to one segment in 443 patients, of whom 370 had DVT isolated to the calf veins (28% of total cohort). In 968 patients with what was previously called “proximal DVT”, the median number of affected segments was three (range 1-5 segments). In this group iliofemoral DVT (at least involving segment four and/or five) was present in 506 patients (38% of total cohort), whereas the remaining patients had femoropopliteal DVT (at least in segment two and/or three but not in four or five). Iliofemoral DVT without thrombus in segments one and two was present in 160 patients (12% of total cohort). This study illustrates the large diversity of thrombus distribution in patients previously described as having “proximal DVT”. Therefore, this term should be abandoned and replaced with iliofemoral and femoropopliteal DVT. Patients with iliofemoral DVT (38%) could be considered for early clot removal; 12% of all patients with DVT would be ideal candidates for such intervention.

Analysis of 1,338 Patients with Acute Lower Limb Deep Venous Thrombosis (DVT) Supports the Inadequacy of the Term “Proximal DVT”

For decades acute lower limb deep venous thrombosis (DVT) has been subdivided into distal DVT (isolated to the calf veins) and proximal DVT (extending above calf vein level). The aim of this study was to analyse the anatomical site and extent of thrombus in a large cohort of patients with acute DVT. A retrospective analysis of all patients aged >18 years, presenting with unilateral DVT according to duplex ultrasound investigation was performed at the University Hospital of Antwerp, Belgium (1994-2012). The anatomical site and extent of thrombus was registered and subdivided into five segments: calf veins (segment 1), popliteal vein (segment 2), femoral vein (segment 3), common femoral vein (segment 4), and iliac veins, with or without inferior vena cava (segment 5). The median age of the 1,338 patients (50% male) included was 62 years (range 18-98 years). Left sided DVT was predominant (57%). DVT was limited to one segment in 443 patients, of whom 370 had DVT isolated to the calf veins (28% of total cohort). In 968 patients with what was previously called "proximal DVT", the median number of affected segments was three (range 1-5 segments). In this group iliofemoral DVT (at least involving segment four and/or five) was present in 506 patients (38% of total cohort), whereas the remaining patients had femoropopliteal DVT (at least in segment two and/or three but not in four or five). Iliofemoral DVT without thrombus in segments one and two was present in 160 patients (12% of total cohort). This study illustrates the large diversity of thrombus distribution in patients previously described as having "proximal DVT". Therefore, this term should be abandoned and replaced with iliofemoral and femoropopliteal DVT. Patients with iliofemoral DVT (38%) could be considered for early clot removal; 12% of all patients with DVT would be ideal candidates for such intervention.

Сравнение отдаленных последствий тромбоза глубоких вен голени и бедренно-подколенного сегмента

Сравнение отдаленных последствий тромбоза глубоких вен голени и бедренно-подколенного сегмента

Low incidence of post-thrombotic syndrome in patients treated with new oral anticoagulants and percutaneous endovenous intervention for lower extremity deep venous thrombosis.

Post-thrombotic syndrome (PTS) is a common complication of deep venous thrombosis (DVT) of the iliofemoral venous system leading to significant morbidity and high health care costs. It has been recently shown that percutaneous endovenous intervention (PEVI) can effectively reduce the incidence of PTS. The role of new oral anticoagulants (NOACs) in combination with PEVI in the reduction of PTS has not been previously studied. This report sought to evaluate the role of PEVI plus NOACs in the reduction of PTS in acute symptomatic femoropopliteal and iliac DVT. We studied 127 patients with acute lower extremity DVT who had undergone PEVI plus administration of NOACs. All had received a minimum of 3 months of anticoagulation with a NOAC following PEVI. The mean follow-up was 22±5 months. The patients were evaluated for development of PTS, bleeding, recurrent venous thromboembolism (VTE), duration of hospitalization and mortality. There was no in-hospital bleeding. The mean duration of hospitalization was 46±9 hours. DVT occurred in two patients who had been later switched to warfarin. There were four non-VTE-related deaths. PTS developed in five patients (3%), two of whom were those who had been switched to warfarin. Their mean Villalta score was 6.2±0.9. We conclude that the combination of PEVI plus NOAC and low dose aspirin is associated with a very low rate of PTS with the severity being only mild. This approach leads to very low rates of bleeding and recurrent VTE and promotes early discharge.

Pharmacomechanical Thrombectomy in the Management of Deep Vein Thrombosis Using the Cleaner Device: An Initial Single-Center Experience

Pharmacomechanical thrombectomy (PMT) has appeared as an effective treatment modality for deep venous thrombosis (DVT). The study aimed to assess the efficacy of the Cleaner™ thrombectomy device for acute DVT. Sixteen consecutive patients presenting with extensive iliofemoral and/or femoropopliteal acute DVT and managed at our institution between February 2013 and May 2014 were retrospectively reviewed. The patients underwent PMT with the Cleaner device after insertion of vena caval filters. For underlying stenotic lesions, balloon angioplasty and/or stent placement was performed. PMT with the Cleaner device was successful in 14 patients with complete restoration of flow. No clinical signs of pulmonary thromboembolism was recorded after the procedure. Thrombectomy failed in 2 patients. For the rest of the patients, balloon angioplasty was performed to relieve underlying stenotic lesions. Nine of them underwent additional stenting. Our initial experience suggests that the Cleaner device can be used in acute DVT. However, further studies involving larger patient populations are warranted to determine long-term results.

Hybrid Operative Thrombectomy for the Treatment of Symptomatic Iliofemoral Deep Venous Thrombosis: Initial Experience and Midterm Results.

In this report, we describe a novel technique for the treatment of iliofemoral deep venous thrombosis (DVT) known as the hybrid operative thrombectomy (HOT), which employs a direct infrainguinal approach (by a single incision) with concomitant retrograde advancement of a balloon catheter through femoral venotomy. The purpose of our study was to assess the feasibility, safety, and perioperative and intermediate outcomes associated with this technique. From July 2011 to May 2014, 32 consecutive patients with symptomatic acute or subacute iliofemoral or femoropopliteal DVT were treated with HOT. Exclusion criteria included symptomatic bilateral iliofemoral DVT and caval involvement at the time of diagnosis (n = 4). The primary end points were as follows: (1) angiographic evidence of restored venous patency at completion of the procedure, (2) duplex findings at intermediate follow-up (≥3 months to 3 years), and (3) clinical follow-up by Villalta and CEAP scales. The symptomatic DVT was located at the left limb in 22 of 28 (78.6%) of the cases, the right limb in six of 28 (21.4%). The inferior vena cava and iliofemoral, femoropopliteal, tibial, and great saphenous veins were involved in 0%, 27 of 28 (96.4%), 19 of 28 (67.9%), seven of 28 (17.9%), and three of 28 (10.7%) of the patients, respectively. Balloon angioplasty was completed in 19 of 28 patients (67.9%) and stent placement in 15 of 28 (53.6%). Mean operative time was 100 minutes (range, 40-190 minutes). Complete (>95%) thrombus removal was obtained in 21 of 28 limbs (75%) and partial (between 80% and 90%) resolution in seven of 28 (25%). At a mean follow-up time of 378 days (range, 94-799 days), duplex ultrasound showed chronic nonocclusive DVT at the surgical iliofemoral, femoropopliteal, tibial, and great saphenous vein segments in 16 of 20 (80%), seven of 20 (35%), four of 20 (20%), and four of 20 (20%) limbs (eight of 28 patients lost to follow-up), respectively. Venous reflux at the surgical iliofemoral segment was found to be nonsignificant (reflux time, 0-0.9 second), mild (1-2 seconds), moderate (2-3 seconds), and severe (>3 seconds) in 15 of 20 (75%), four of 20 (20%), 0%, and one of 20 (5%), respectively. Venous reflux at the surgical femoropopliteal segment was found to be nonsignificant, mild, moderate, and severe in 10 of 20 (50%), five of 20 (25%), two of 20 (10%), and three of 20 (15%), respectively. Acute iliofemoral DVT developed in one patient in the early postoperative period and required take back for revision. At a mean follow-up time of 504 days (range, 100-921 days), the clinical CEAP and Villalta scores were 0.85 (range, 0-3) and 2.25 (range, 0-4), respectively. No patients had venous ulcers at follow-up. When it is used as a standalone procedure, the HOT technique can successfully remove venous thrombus safely and effectively and is associated with excellent clinical results at intermediate follow-up.

Prevalence and Clinical Outcome of Free-Floating Thrombus Formation in Lower Extremity Deep Veins.

Most published guidelines for treatment of acute and subacute deep venous thrombosis (DVT) recommend early ambulation over initial bed rest. However, formation of free-floating thrombus in the lower extremity deep veins carries a high risk of fatal pulmonary embolism (PE) during ambulation. Furthermore, the natural history of free-floating thrombus in this patient population is not known. The purpose of this study was to identify the prevalence and outcome of free-floating thrombus among patients with acute DVT. Between January 2013 and December 2013, 427 patients were diagnosed as having DVT by compression ultrasound. The anatomic distributions of the thrombi were divided into iliofemoral, femoropopliteal, and calf DVT. The ultrasound features of the thrombi were classified as firmly or loosely attached and free-floating. PE was confirmed with computed tomography angiography. Among 427 patients with DVT, seven (1.7%) were found to have free-floating thrombus. The risk factors for DVT included recent knee surgery in two (28.5%), recent hip surgery in one (14.3%), immobilization in one (14.3%), malignant neoplasm in one (14.3%), hormone replacement therapy in one (14.3%), and stroke in one (14.3%). Initial treatment of these patients included bed rest and anticoagulation therapy. Two of these patients underwent temporary insertion of an inferior vena cava filter. The thrombus was located predominantly in the femoropopliteal segment (five patients, 71.4%), and the prevalence of femoropopliteal DVT was significantly higher in patients with free-floating thrombus than in those without (P = .0002). PE was found in three patients (42.9%), and the incidence of PE was significantly higher in patients who had free-floating thrombus than in those who did not (P = .0001). The free-floating thrombus resolved spontaneously in four patients (57.1%) within a mean period of 19 days. On the other hand, the thrombus became firmly attached to the vein wall in the remaining three patients (42.9%) within a mean period of 9 days, leading to secondary thrombus recanalization. No further thromboembolic complications were encountered in these patients. Although the prevalence of free-floating thrombus formation is low among patients with DVT, it can be detected by compression ultrasound in daily practice. Our data show that the natural history of free-floating thrombus treated by anticoagulation can be largely classified into two patterns: early spontaneous thrombus resolution and initial adhesion to the vein wall with secondary thrombus recanalization. Insertion of an inferior vena cava filter can be reserved for patients in whom anticoagulation is contraindicated.

8:45 AM Abstract No. 25 - Recanalization of chronic femoropopliteal deep venous thrombosis in patients suffering from post thrombotic syndrome: a safe and effective approach to improving quality of life

adjunctive use of endovascular maneuvers other than PMT and CDT were recorded. Duration of thrombolysis (hours), total amount of administered t-PA (mg) and length of hospital stay (days) were statistically compared using the Wilcoxon RankedSum test, and the presence of grade III thrombus clearance at completion of endovascular therapy was statistically compared using the Fisher Exact test. A P value o 0.05 indicated a statistically significant difference. Results: Compared to CDT alone, use of the Trellis PMT þ CDT resulted in a greater degree of Grade III thrombus clearance (7/8 vs. 10/27, Po0.05) at completion of endovascular therapy. There were no statistically significant differences in length of hospital stay (P40.05), duration of thrombolysis (P40.05) or amount of administered tPA (P40.05) between the two treatment groups. Conclusion: Compared to CDT alone, Trellis PMT þ CDT improves the degree of thrombus clearance in patients with acute upper extremity DVT.

Rheolytic-Accelerated Pharmacomechanical Directional "RAPID" Thrombectomy Technique: A Method for Rapid Clot Removal with Reduced Need for Catheter-Directed Thrombolysis in Patients with Acute DVT.

BackgroundInherent to mechanical thrombectomy devices is the lack of “complete” thrombus removal resulting in the need for catheter-directed thrombosis (CDT). Our goal is to evaluate the efficacy of the RAPID thrombectomy technique for the treatment of acute deep venous thrombosis (DVT).MethodsA single-center registry of 313 lower extremities in 301 patients treated for acute DVT between 1999 and 2012 was reviewed. Patients underwent pharmacomechanical thrombectomy (PMT) using the RAPID thrombectomy technique, which involves a 6F rheolytic thrombectomy catheter placed coaxially through a directional 8F guiding catheter used in a spiraling fashion, allowing for wall-to-wall thrombectomy. Extent of clot removal and the need for adjunctive CDT, percutaneous transluminal angioplasty, and stenting were evaluated venographically. Follow-up with ultrasound was performed.ResultsA total of 92 limbs demonstrated femoropopliteal DVT, while 221 had iliofemoral DVT, with IVC involvement in 57. Thrombectomy by venography was complete (>90% removal + flow) in 203 (65%), substantial (50% to 90% removal + flow) in 75 (24%), partial (<50%) in 31 (10%), and minimal in 4 (1%) limbs following initial PMT. Flow was successfully restored in 90%. A total of 166 (53%) patients underwent additional CDT with an average infusion time of 17.7 hours; 47% of cases were completed in one session. Eighty-six percent were completed in <24 hours. Stenting was performed in 106 (34%) limbs. Binary patency by ultrasound was 94%, 90%, and 77% at 3, 6, and 12 months.ConclusionsThe RAPID thrombectomy technique is effective for rapid removal of thrombus in patients with acute DVT with significant reduction, in the need for, and length of, CDT. BackgroundInherent to mechanical thrombectomy devices is the lack of “complete” thrombus removal resulting in the need for catheter-directed thrombosis (CDT). Our goal is to evaluate the efficacy of the RAPID thrombectomy technique for the treatment of acute deep venous thrombosis (DVT). Inherent to mechanical thrombectomy devices is the lack of “complete” thrombus removal resulting in the need for catheter-directed thrombosis (CDT). Our goal is to evaluate the efficacy of the RAPID thrombectomy technique for the treatment of acute deep venous thrombosis (DVT). MethodsA single-center registry of 313 lower extremities in 301 patients treated for acute DVT between 1999 and 2012 was reviewed. Patients underwent pharmacomechanical thrombectomy (PMT) using the RAPID thrombectomy technique, which involves a 6F rheolytic thrombectomy catheter placed coaxially through a directional 8F guiding catheter used in a spiraling fashion, allowing for wall-to-wall thrombectomy. Extent of clot removal and the need for adjunctive CDT, percutaneous transluminal angioplasty, and stenting were evaluated venographically. Follow-up with ultrasound was performed. A single-center registry of 313 lower extremities in 301 patients treated for acute DVT between 1999 and 2012 was reviewed. Patients underwent pharmacomechanical thrombectomy (PMT) using the RAPID thrombectomy technique, which involves a 6F rheolytic thrombectomy catheter placed coaxially through a directional 8F guiding catheter used in a spiraling fashion, allowing for wall-to-wall thrombectomy. Extent of clot removal and the need for adjunctive CDT, percutaneous transluminal angioplasty, and stenting were evaluated venographically. Follow-up with ultrasound was performed. ResultsA total of 92 limbs demonstrated femoropopliteal DVT, while 221 had iliofemoral DVT, with IVC involvement in 57. Thrombectomy by venography was complete (>90% removal + flow) in 203 (65%), substantial (50% to 90% removal + flow) in 75 (24%), partial (<50%) in 31 (10%), and minimal in 4 (1%) limbs following initial PMT. Flow was successfully restored in 90%. A total of 166 (53%) patients underwent additional CDT with an average infusion time of 17.7 hours; 47% of cases were completed in one session. Eighty-six percent were completed in <24 hours. Stenting was performed in 106 (34%) limbs. Binary patency by ultrasound was 94%, 90%, and 77% at 3, 6, and 12 months. A total of 92 limbs demonstrated femoropopliteal DVT, while 221 had iliofemoral DVT, with IVC involvement in 57. Thrombectomy by venography was complete (>90% removal + flow) in 203 (65%), substantial (50% to 90% removal + flow) in 75 (24%), partial (<50%) in 31 (10%), and minimal in 4 (1%) limbs following initial PMT. Flow was successfully restored in 90%. A total of 166 (53%) patients underwent additional CDT with an average infusion time of 17.7 hours; 47% of cases were completed in one session. Eighty-six percent were completed in <24 hours. Stenting was performed in 106 (34%) limbs. Binary patency by ultrasound was 94%, 90%, and 77% at 3, 6, and 12 months. ConclusionsThe RAPID thrombectomy technique is effective for rapid removal of thrombus in patients with acute DVT with significant reduction, in the need for, and length of, CDT. The RAPID thrombectomy technique is effective for rapid removal of thrombus in patients with acute DVT with significant reduction, in the need for, and length of, CDT.

Treatment of Chronic Deep Vein Thrombosis Using Ultrasound Accelerated Catheter-directed Thrombolysis

To evaluate the feasibility, efficacy and safety of ultrasound-accelerated catheter-directed thrombolysis (UACDT) in the delayed treatment of lower extremity deep venous thrombosis (DVT). Twelve patients with unilateral iliofemoral or femoropopliteal DVT (mean symptom duration 92 ± 44 days) were prospectively investigated. UACDT was performed using recombinant human tissue plasminogen activator delivered using the EKOS EkoSonic system. Stents were deployed if indicated by post-procedure venography. Follow-up comprised weekly duplex ultrasound for 1 month and monthly thereafter. Successful thrombolysis occurred in 11/12 limbs (92%; complete 6/12, partial 5/12) after a mean infusion time of 26 ± 7 hours. 2/12 patients required angioplasty and stent insertion. At a mean follow-up of 9 (6-15) months, 10/11 (91%) veins were patent whereas 1/11 re-occluded at 2 months (patient with protein-C deficiency). 2/11 limbs developed symptoms/signs of post-thrombotic syndrome and 3/11 had developed deep vein reflux (duplex ultrasound). 2/12 patients experienced peri-catheter bleeding but no major hemorrhage or symptomatic pulmonary embolism occurred. This preliminary evidence suggests that UACDT may be a safe and effective option for the delayed treatment of lower limb DVT.

Catheter-directed Thrombolysis with Argatroban and tPA for Massive Iliac and Femoropopliteal Vein Thrombosis

Catheter-directed thrombolysis (CDT) is a highly effective approach in the treatment of deep venous thrombosis (DVT). There are no data on the primary use of CDT with argatroban and tissue plasminogen activator (tPA) in patients without heparin-induced thrombocytopenia (HIT). The aim of this study was to evaluate the efficacy and safety of the combined administration of argatroban and tPA during CDT for massive DVT in patients without HIT. Thirty-three patients with massive symptomatic iliac and femoropopliteal DVT underwent CDT with tPA and argatroban within 28 ± 6 h of presentation. The dose of tPA was 0.75-1 mg/h through the infusion port and that of argatroban at 0.3-1 μg/kg/min through the side port of the sheath. The patients were evaluated for the efficacy and safety of CDT and recurrent symptomatic venous thromboembolism (VTE) at a mean follow-up of 22 months. There was no bleeding or iatrogenic pulmonary embolism with the CDT regimen we used. Grade III lysis (complete resolution of thrombus on venography) was achieved in 30 patients (91 %). In 3 patients with additional inferior vena cava filter thrombosis, further thrombectomy of the filter was required. No patient developed recurrent VTE. Concomitant administration of argatroban and tPA is a highly safe and effective regimen for CDT for massive DVT.

The Role of Ultrasound to Identify Nonthrombotic Lower Extremity Pathology

Accreditation in peripheral venous testing can be obtained based on femoropopliteal duplex ultrasound evaluation, and many laboratories limit their examination to this segment only. This simplified protocol detects acute femoropopliteal deep venous thrombosis (DVT) but misses calf vein DVT, superficial venous thrombosis, chronic DVT, venous reflux, and other nonvenous findings potentially responsible for pateints' presenting conditions. A protocol limited to the femoropopliteal segment results in additional unnecessary testing and can create patient dissatisfaction. We evaluated the differences in the diagnosis between a limited femoropopliteal vs a complete approach to the venous ultrasound evaluation of the lower extremities in patients examined in an outpatient vascular laboratory. A database with the complete ultrasound examinations of the lower extremity, including the common femoral, deep femoral, popliteal, tibial and peroneal veins, calf musclar veins, and great and small saphenous veins, performed in 1208 consecutive patients from July 2009 to February 2010 was queried. Of the 1208 patients, acute femoropopliteal DVT was found in 20 (1.66%), acute infrapopliteal DVT in 36 (2.98%), chronic femoropopliteal DVT in 42 (48%), and superficial thrombophlebitis of the lower extremities in 84 (6.95%). In addition, deep venous insufficiency (>500 milliseconds) was found in 385 (31.87%) and superficial venous insufficiency in 212 (17.55%). A mass was found in 64 (5.3%), comprising 10 cysts, four hematomas, 46 solid masses, and three aneurysms. Limited femoropopliteal ultrasound examination for acute DVT would have only detected a small percentage of the positive findings. These data suggest that the duplex examination can be used to further delineate the cause of outpatients' symptoms compared with the limited protocol.

Assessment of Deep Venous Thrombosis by Grayscale Median Analysis of Ultrasound Images

This study aimed to determine whether grayscale median (GSM) ultrasound (US) analysis could differentiate acute from subacute femoropopliteal deep venous thrombosis (DVT) classified based on (a) the time of symptoms onset and (b) sonographers' evaluation of US images. Patients who had US because of suspected DVT were included. Patients with history of previous DVT, with normal US results or US with findings of isolated calf thrombosis were excluded. A total of 128 venous segments of 63 patients were analyzed. Thrombosed veins and adjacent arteries images were recorded. Thrombi GSM were calculated. Grayscale median was compared with (a) the time of symptoms onset and (b) US image thrombi classification as acute or subacute done by 2 sonographers blinded to patient information. Statistical analysis included GSM Pearson intraobserver variability and t test comparisons of GSM means for (a) short versus long onset periods and (b) acute versus subacute US class, χ comparison between onset history and US class, creation of GSM accuracy, predictive values, and sensitivity curves for acute versus subacute DVT. Intraobserver variability correlation varied between 0.92 and 0.95. Thrombus mean GSM was 23 ± 12 versus 31 ± 16 if symptoms onset was shorter or longer than 2 weeks (P = 0.004). Mean GSM was 20 ± 11 versus 35 ± 14 for acute versus subacute thrombi (P < 0.001). Acute thrombi correlated with onset shorter than 2 weeks (P < 0.001). Grayscale median less than 13, equal to 22, or 33 or less had 85% positive predictive value (17/20), 77% accuracy (98/128), and 90% sensitivity (53/59) to differentiate acute from subacute thrombi. Grayscale median of US images documenting femoropopliteal DVT correlated with (a) the time between symptoms onset and US examination and (b) the sonographers' interpretation of acute versus subacute thrombosis.

Prospective comparison of emergency physician–performed venous ultrasound and CT venography for deep venous thrombosis

Background Venous thromboembolic disease is a major cause of mortality and morbidity. Objectives The aim of this study is to compare emergency physician–performed ultrasound (EPPU) of the lower extremities with CT venography (CTV) in emergency department (ED) patients undergoing workup for pulmonary embolism (PE). Methods This was a prospective study performed at a busy academic ED. Adult patients (>18) undergoing workup for PE were eligible for the study; enrollment was based on a convenience sample, during hours worked by the investigators. Study patients underwent EPPU of the lower extremities followed by CT angiogram (CTA) of the chest and CTV of the lower extremities. Sensitivity and specificity of the ultrasound examination were calculated using CTV as the gold standard. Results A total of 61 patients were enrolled. Of 61 patients, 50 (82%; 95% confidence interval [CI], 72%-91%) had negative workups; 11 (18%; 95% CI, 8%-27%) were noted to have PE on CTA; 6 (10%; 95% CI, 2%-17%) were noted to have lower extremity deep venous thrombosis (DVT) on both EPPU and CTV evaluation; whereas 1 patient was found to have an external iliac DVT on CTV, which was not noted on EPPU. All patients with DVT (by either EPPU or CTV) were found to have PE on CTA. Sensitivity and specificity of EPPU when compared to CTV in the diagnosis of DVT was 86% (95% CI, 42%-99%) and 100% (95% CI, 91%-100%), respectively. Conclusions Emergency physician–performed ultrasound produces results consistent with CTV in the diagnosis of femoropopliteal DVT. More proximal clots are not evaluated with EPPU and thus may result in a false negative.

Comparison of duplex ultrasonography and venography in the diagnosis of deep venous thrombosis

Sixty-five patients with suspected deep venous thrombosis (DVT) in 68 limbs were entered consecutively into a study to compare venography with duplex ultrasonography scanning. Both tests were performed on 64 limbs, venography being contraindicated in four. Overall, duplex scanning correctly identified 86 per cent of DVTs diagnosed on venography and correctly excluded 80 per cent with negative venograms. Nearly all errors arose in the diagnosis of calf DVT. In the femoral vein duplex scanning had a specificity of 100 per cent and a sensitivity of 95 per cent. In addition, duplex scanning provided data on the limb not undergoing venography. Of 55 limbs that underwent bilateral duplex scanning, five had thrombus in the femoropopliteal segment and a negative contralateral venogram. In addition, three Baker's cysts were diagnosed. Duplex scanning can be used in patients in whom venography is contraindicated and may also provide information about the contralateral limb. We regard femoropopliteal duplex scanning as sufficiently accurate that treatment can be initiated on the basis of the scan. Duplex scanning should replace venography as the standard method of diagnosing femoropopliteal DVT; radiographic studies should now be required only when the scan result is in doubt.

Generalized changes in venous distensibility in postthrombotic patients

Introduction In situ biomechanical properties of peripheral large veins were compared between asymptomatic young patients who had previously unilateral femoro-popliteal deep venous thrombosis (DVT) and age-matched, healthy controls; the aim of this study was to assess local or generalized alterations of venous wall biomechanics in postthrombotic patients. Patients and methods Inner diameters of both common femoral veins, right axillary vein, and right internal jugular veins were measured in two directions by ultrasonography. Venous pressure was altered by posture changes (standing and lying) and by application of graded and controlled Valsalva. Ten postthrombotic young patients without any symptoms and 11 age-matched control subjects were included. Results In postthrombotic patients, both the affected and unaffected common femoral vein diameters and capacities were larger at low transmural pressures than those for the control group, but they demonstrated significantly less distensibility when higher pressures were applied. Similarly, in the internal jugular vein, capacity without Valsalva was significantly higher in postthrombotic patients and distensibility was reduced (statistically significant in the erect position). Pressure-induced changes in axillary vein diameter were negligible. Conclusions In situ diameter and capacity changes, and in situ distensibility of the femoral veins on both sides (i.e., the side of previous thrombosis as well as the disease-free side) and of the jugular veins are reduced in the young DVT patients compared to veins of the age-matched, healthy controls. The pathophysiological mechanism of generalized venous wall changes in these young DVT patients remains unknown.