Assessment of the Probability of Post-thrombotic Syndrome in Patients with Lower Extremity Deep Venous Thrombosis.

This study was performed to assess the probability of post-thrombotic syndrome (PTS) after treatment of lower extremity deep venous thrombosis (LEDVT). Patients with LEDVT undergoing their first treatments in Nanjing First Hospital from January 2013 to December 2014 were enrolled in this study (156 patients were enrolled in the training cohort, and 135 patients were enrolled in the validation cohort). 51 and 45 patients developed PTS in the two cohorts, respectively. Independent risk factors for PTS were investigated in the training cohort, and these independent risk factors were employed to develop the APTSD scoring system with which to predict the probability of PTS. Four independent risk factors for PTS were identified: iliac vein compression syndrome, residual iliac-femoral vein thrombosis, residual femoral-popliteal vein thrombosis and insufficient anticoagulation. Patients in the training cohort were divided into 2 groups according to the APTSD score of ≤7.0 and >7.0 points regarding the probability of PTS (median PTS-free time, 21.82 vs. 18.84 months; P < 0.001). The accuracy of this score system was 81.7% for the training cohort and 82.5% for the validation cohort. Patients with an APTSD score of >7.0 points may have an increased probability of developing PTS.

Inflammation modulates murine venous thrombosis resolution in vivo: assessment by multimodal fluorescence molecular imaging.

OBJECTIVE: Assessment of thrombus inflammation in vivo could provide new insights into deep vein thrombosis (DVT) resolution. Here, we develop and evaluate 2 integrated fluorescence molecular-structural imaging strategies to quantify DVT-related inflammation and architecture and to assess the effect of thrombus inflammation on subsequent DVT resolution in vivo. METHODS AND RESULTS: Murine DVT were created with topical 5% FeCl(3) application to thigh or jugular veins (n=35). On day 3, mice received macrophage and matrix metalloproteinase activity fluorescence imaging agents. On day 4, integrated assessment of DVT inflammation and architecture was performed using confocal fluorescence intravital microscopy. Day 4 analyses showed robust relationships among in vivo thrombus macrophages, matrix metalloproteinase activity, and fluorescein isothiocyanate-dextran deposition (r>0.70; P<0.01). In a serial 2-time point study, mice with DVT underwent intravital microscopy at day 4 and day 6. Analyses revealed that the intensity of thrombus inflammation at day 4 predicted the magnitude of DVT resolution at day 6 (P<0.05). In a second approach, noninvasive fluorescence molecular tomography-computed tomography was used and detected macrophages within jugular DVT (P<0.05 versus sham controls). CONCLUSIONS: Integrated fluorescence molecular-structural imaging demonstrates that the DVT-induced inflammatory response can be readily assessed in vivo and can inform the magnitude of thrombus resolution.

Chronic deep venous obstruction: definition, prevalence, diagnosis, management.

Ilio-caval venous obstruction has an important role in the expression of symptomatic chronic venous disease regardless of aetiology. The presence of obstruction has been more or less previously ignored and emphasis placed on reflux alone. Stenting of the ilio-femoral veins guided by intravascular ultrasound (IVUS) can now be performed with low morbidity and mortality using appropriate technique. Current diagnostic modalities do not allow a definitive assessment of haemodynamically critical venous obstruction, which hampers selection of limbs for treatment. The diagnosis must be based on morphological studies (preferably IVUS) in patient selected with specific history, signs and symptoms. A high index of suspicion and generous use of morphological investigations are critical in the initial recognition of venous outflow obstruction. Stenting of the ilio-femoral vein appears to be durable with a substantial improvement in limb pain and swelling, high rate of ulcer healing, enhanced quality of life and decreased disability. The beneficial clinical outcome occurs regardless of the presence of remaining reflux, adjunct saphenous procedures or aetiology of obstruction.

Thrombolysis for lower extremity deep venous thrombosis.

Catheter-directed thrombolysis (CDT) has been proposed as an alternative mode of therapy to anticoagulation in patients with massive, symptomatic deep vein thrombosis of the extremity. The major goal of therapy is to rapidly restore venous blood flow, reduce the pain and edema of the extremity, preserve venous valve function, and reduce chronic symptoms related to chronic venous hypertension (postthrombotic syndrome). In patients with iliofemoral deep venous thrombosis (DVT) standard angiographic techniques are used to instrument a lower extremity vein (popliteal) and venography is performed followed by catheter-directed infusion of a plasminogen activator directly into the thrombus. Following lytic infusion, the interventionalist must evaluate the venous drainage to determine if there is an anatomic lesion that requires further endovascular treatment (eg, iliac vein compression syndrome). Posttreatment therapy usually consists of warfarin therapy and venous compression stockings for at least 3 to 6 months. The purpose of this article is to review the technical approach used in treating iliofemoral DVT and highlight the hurdles that face interventionalists in attempting to broaden this procedure to most types of lower extremity DVT.

Assessment of the patency of microvascular venous anastomosis.

There is an absence of data on the timing of occlusion of vessels after anastomosis, and on the possible subsequent reopening (recanalization) of these vessels. This lack of information may be an important factor in the wide discrepancies found among reported patency rates for laboratory microvascular repair. In this study, a total of 300 standard microsurgical anastomoses were performed on rat femoral veins. The patency of each anastomosis was assessed at regular intervals within a 2-week study period. These results showed that the majority of venous occlusions occurred within 1 day after repair. Recanalization of the occluded vein was first seen at day 3 postoperatively. Recanalization was observed over a 2-week postoperative period with increasing frequency. The authors conclude that the optimal time to assess the technical outcome of experimental venous patency is 1 to 2 days after the repair.

Duplex scan-directed placement of inferior vena cava filters: a five-year institutional experience.

PURPOSE: The purpose of this study was the assessment of the safety, efficacy, and hospital charges of bedside duplex ultrasound-directed inferior vena cava (IVC) filter placement. METHODS: All duplex ultrasound-directed IVC filters that were placed from August 8, 1995, to December 31, 2000, are reviewed. Chart review combined with mailed questionnaires and telephone follow-up examinations were used to collect demographic and outcome data. RESULTS: Three hundred twenty-five patients underwent evaluation, and 284 underwent duplex ultrasound-directed IVC filter placement. Two hundred three (71%) were male patients, and 81 (29%) were female patients. Poor IVC visualization, IVC thrombosis, and unsuitable anatomy prevented duplex-directed filter placement in 41 patients (12%). Indication for filter placement included venous prophylaxis in the absence of thromboembolism in 235 patients (83%), contraindication to anticoagulation therapy in 34 patients (12%), prophylaxis with therapeutic anticoagulation therapy in the presence of thromboembolism in 7 patients (2%), and complication of anticoagulation therapy in 8 patients (3%). There were no procedure-related deaths or septic complications. Technical complications occurred in 12 patients (4%). Filter misplacement occurred in 6 patients (2%), access thrombosis in 1 (<1%), migration in 1 (<1%), bleeding in 1 (<1%), and IVC occlusion in 3 (1%). Pulmonary emboli after IVC filter placement occurred in one patient with a misplaced filter. Average hospital charges related to duplex ultrasound-directed filter placement were $2388 less than fluoroscopic placement charges in the year 2000. CONCLUSION: Our experience indicates that duplex ultrasound-directed IVC filter placement is safe, cost-effective, and convenient for patients who need IVC filter placement.

Compression ultrasonography of the leg veins in patients with clinically suspected pulmonary embolism: is a more extensive assessment of compressibility useful?

We performed a multi-center study in consecutive patients with suspected pulmonary embolism to compare the diagnostic accuracy of a two-point compression ultrasonography (only the common femoral vein and popliteal vein) with an extensive examination of compressibility (from the common femoral vein until the trifurcation of calf veins). A total of 479 patients underwent the two-point compression ultrasonography. The prevalence of pulmonary embolism was 32%. The sensitivity and specificity of this procedure were 23% (95% CI 19-26) and 98% (95% CI 96-99), respectively. Extensive compression ultrasonography was performed in 461 (96%) of these 479 patients and showed comparable accuracy indices (sensitivity 25%, 95% Cl 20-28 and specificity 97%, 95% CI 95-99). We conclude that compression ultrasonography has a limited sensitivity for the detection of thrombosis in patients with acute pulmonary embolism within 24 h of presentation. A more extensive assessment of compressibility of the leg veins in these patients has no additional value as compared to the two-point assessment.

Sonographic estimates of vein size in the lower extremities: subjective assessment compared with direct measurement.

PURPOSE: We studied whether subjective impression of vein size is a valid means of assessment during sonographic evaluation for deep vein thrombosis. METHODS: Diameter was assessed at 5 predetermined venous segments on 975 legs of 721 patients referred for evaluation for lower extremity deep vein thrombosis. The sonographer recorded a subjective assessment of whether the venous segment was enlarged, normal, or narrowed based on a visual impression of sonographic images obtained without compression. This subjective impression was then compared with the absolute measurements of vein diameter and vein diameter:artery diameter ratio at each segment. RESULTS: A significant correlation was found between the subjective characterization of vein size as enlarged, normal, and narrowed and both the absolute vein diameter and the vein:artery ratio at all 5 segments. CONCLUSIONS: Vein size can be reliably categorized by the subjective impression of experienced sonographers. Therefore, actual measurement of the vein diameter is not necessary in the evaluation for deep vein thrombosis in the majority of patients.

Venous valvular assessment after retrograde catheterization.

PURPOSE: To determine whether retrograde passage of a coaxial infusion system (Mewissen-Katzen catheter and guide wire) into extremity veins with valves causes damage. MATERIALS AND METHODS: Retrograde common femoral vein puncture and passage of an infusion wire-catheter system through the superficial femoral and popliteal veins of one leg were performed in five anesthetized pigs. Heparinized saline was then infused via the catheter and wire for approximately 8 hours. The pigs were then killed, and the femoropopliteal veins were removed from both legs of each pig and examined by a pathologist. The noncatheterized leg veins served as a control in each animal. RESULTS: Valvular damage occurred in one of five pigs. This may have resulted from leg movement during catheter passage in this animal. CONCLUSION: Retrograde passage of a catheter-guide-wire infusion system caused minimal to no damage to the venous valves of pigs. This suggests that human venous valves may be spared injury during catheter-directed venous thrombolysis. Further study of catheter manipulation in a model of deep venous thrombosis is needed.

[Ambulatory treatment of deep venous thrombosis. From data of a study of 108 patients, an evaluation of its cost and its efficacy]. / Traitement ambulatoire des thromboses veineuses profondes. A partir des données d'une étude portant sur 108 patients, évaluation de son coût et de son efficacité.

UNLABELLED: The study deals with the efficiency and the cost of an ambulatory treatment of deep venous thrombosis by means of Fraxiparine, contention and phlebotonics. 108 patients have been treated. The thrombosis affected the deep veins of the leg in 26 p. cent, the popliteal vein in 9.2 p. cent, the femoropopliteal axis in 19 p. cent as well as superficial thrombosis extended to the depth in 16.6 p. cent. The diagnosis was performed clinically and by ultrasound when phlebography was used in a few cases only (7.4 p. cent). The initial treatment lasted 9.8 days (75 p. cent) 15 days (12 p. cent) and more (12.8 p. cent). Complete re-permeabilization has been noticed in 35.8 p. cent on the 10th day, in 57.5 between the 15th and 30th day. Beside some minor complications 2 recurrences of the thrombosis occurred and 2 patients presented Pulmonary Embolism. They were sent to hospital. The average cost for a treatment was 789 FF for consultation, 1,818 FF for nursing, 1,405 FF for Fraxiparine and 325 FF for contention. CONCLUSION: hospitalization is sometimes indispensable, sometimes avoidable ... let us make a good choice.

Noninvasive assessment of microvessels with the duplex scanner.

This study was undertaken to determine if a duplex scanner equipped with a new 10 MHz probe could accurately evaluate microvascular anastomotic patency. The overall predictive accuracy of the duplex scanner was 90% (p less than 0.0001) with no difference noted among the three main anastomotic groups examined--acute artery, acute vein, and long-term artery. There was, however, a statistically significant difference (p less than 0.05) in the ability to interpret vessels that were patent (100%) versus those that were partially occluded (73%) or occluded (88%). It is believed that the duplex scanner has potential applications to preoperatively and intraoperatively study microvessels and postoperatively to supplement other techniques in monitoring acute and long-term anastomotic patency.