Benign outcome of objectively proven spontaneous recanalization of internal carotid artery occlusion.

OBJECTIVE: Spontaneous recanalization of intracranial internal carotid artery (ICA) occlusion is frequent in embolic strokes. Spontaneous recanalization of the extracranial portion of the ICA occlusion of atherosclerotic or embolic origin is only anecdotally reported, and data are lacking about its incidence, natural history, and outcome in long-term follow-up. METHODS: Consecutive patients with ICA occlusion were prospectively identified and followed-up to detect the incidence of a spontaneous recanalization. Patients with objectively confirmed recanalization were prospectively followed-up to observe their natural history and the onset of new cerebrovascular events. ICA occlusion and spontaneous recanalization were diagnosed by means of color-coded Doppler ultrasound imaging or selective contrast angiography, or both. All patients were evaluated and treated for atherosclerotic risk factors. RESULTS: Spontaneous recanalization occurred in 16 of 696 patients (2.3%; 95% confidence interval, 1.3%-3.7%) with ICA occlusion after a mean interval of 38 months from the diagnosis of occlusion. Spontaneous recanalization was detected with color-coded Doppler ultrasound imaging and with selective contrast angiography, with a complete agreement of diagnostic findings. Two patients presented with symptomatic spontaneous recanalization. All patients with spontaneous recanalization were asymptomatic after a mean follow-up of 66.2 months. CONCLUSIONS: Spontaneous recanalization of previously occluded extracranial ICAs is more frequent than anticipated. Once it occurs, spontaneous recanalization seems to have a benign long-term course.

Low-molecular-weight heparin versus compression stockings for thromboprophylaxis after knee arthroscopy: a randomized trial.

BACKGROUND: Knee arthroscopy, the most common orthopedic operation worldwide, carries a definite risk for deep venous thrombosis; however, postsurgical thromboprophylaxis is not routinely recommended. OBJECTIVE: To evaluate whether low-molecular-weight heparin (LMWH) better prevents deep venous thrombosis and does not cause more complications than graduated compression stockings in adults having knee arthroscopy. DESIGN: Assessor-blind, randomized, controlled trial. SETTING: The Department of Knee Surgery, Abano Terme Clinic, Abano Terme (knee surgery, random assignment, and bleeding event survey), and the Unit of Angiology, University Hospital of Padua, Padua (efficacy outcomes evaluation, follow-up, data management, and analysis), Italy. PATIENTS: 1761 consecutive patients undergoing knee arthroscopy between March 2002 and January 2006. INTERVENTION: Patients were randomly assigned to wear full-length graduated compression stocking for 7 days (660 patients) or to receive a once-daily subcutaneous injection of LMWH (nadroparin, 3800 anti-Xa IU) for 7 days (657 patients) or 14 days (444 patients). The data and safety monitoring board prematurely stopped the 14-day heparin group after the second interim analysis. MEASUREMENTS: Combined incidence of asymptomatic proximal deep venous thrombosis, symptomatic venous thromboembolism, and all-cause mortality (primary efficacy end point) and combined incidence of major and clinically relevant bleeding events (primary safety end point). All patients had bilateral whole-leg ultrasonography at the end of the allocated prophylactic regimen or earlier if indicated. All patients with normal findings were followed for 3 months, and none was lost to follow-up. RESULTS: The 3-month cumulative incidence of asymptomatic proximal deep venous thrombosis, symptomatic venous thromboembolism, and all-cause mortality was 3.2% (21 of 660 patients) in the stockings group, 0.9% (6 of 657 patients) in the 7-day LMWH group (absolute difference, 2.3 percentage points [95% CI, 0.7 to 4.0 percentage points]; P = 0.005), and 0.9% (4 of 444 patients) in the prematurely stopped 14-day LMWH group. The cumulative incidence of major or clinically relevant bleeding events was 0.3% (2 of 660 patients) in the stockings group, 0.9% (6 of 657 patients) in the 7-day LMWH group (absolute difference, -0.6 percentage point [CI, -1.5 to 0.2 percentage points]), and 0.5% (2 of 444 patients) in the 14-day LMWH group. LIMITATIONS: The study was not double-blind or double-dummy. Almost half of the events making up the composite outcome measure were distal deep venous thromboses. Stockings were used instead of placebo because of local prophylaxis policies. CONCLUSION: In patients undergoing knee arthroscopy, prophylactic LMWH for 1 week reduced a composite end point of asymptomatic proximal deep venous thrombosis, symptomatic venous thromboembolism, and all-cause mortality more than did graduated compression stockings.

Serial 2-point ultrasonography plus D-dimer vs whole-leg color-coded Doppler ultrasonography for diagnosing suspected symptomatic deep vein thrombosis: a randomized controlled trial.

CONTEXT: Patients with suspected deep vein thrombosis (DVT) of the lower extremities are usually investigated with ultrasonography either by the proximal veins (2-point ultrasonography) or the entire deep vein system (whole-leg ultrasonography). The latter approach is thought to be better based on its ability to detect isolated calf vein thrombosis; however, it requires skilled operators and is mainly available only during working hours. No randomized comparisons are yet available evaluating the relative values of these 2 strategies. OBJECTIVE: To assess if the 2 diagnostic strategies are equivalent for the management of symptomatic outpatients with suspected DVT of the lower extremities. DESIGN, SETTING, AND PATIENTS: A prospective, randomized, multicenter study of consecutive symptomatic outpatients (n = 2465) with a first episode of suspected DVT of the lower extremities who were randomized to undergo 2-point or whole-leg ultrasonography. Data were taken from ultrasound laboratories of 14 Italian universities or civic hospitals between January 1, 2003, and December 21, 2006. Patients with normal ultrasound findings were followed up for 3 months, with study completion on March 20, 2007. MAIN OUTCOME MEASURE: Objectively confirmed 3-month incidence of symptomatic venous thromboembolism in patients with an initially normal diagnostic workup. RESULTS: Of 2465 eligible patients, 345 met 1 or more exclusion criteria and 22 refused to participate; therefore, 2098 patients were randomized to either 2-point (n = 1045) or whole-leg (n = 1053) ultrasonography. Symptomatic venous thromboembolism occurred in 7 of 801 patients (incidence, 0.9%; 95% confidence interval [CI], 0.3%-1.8%) in the 2-point strategy group and in 9 of 763 patients (incidence, 1.2%; 95% CI, 0.5%-2.2%) in the whole-leg strategy group. This met the established equivalence criterion (observed difference, 0.3%;95% CI, -1.4% to 0.8%). CONCLUSION: The 2 diagnostic strategies are equivalent when used for the management of symptomatic outpatients with suspected DVT of the lower extremities. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00353093.

Simplification of the diagnostic management of suspected deep vein thrombosis.

BACKGROUND: The standard diagnostic approach in patients with suspected deep vein thrombosis is to repeat the compression ultrasonography after 1 week in all patients with an initial normal result. We hypothesized that a normal finding of a D-dimer assay safely obviates the need for repeated ultrasonography. In addition, we evaluated the potential value of a pretest probability assessment for this purpose. METHODS: At presentation, consecutive outpatients with suspected thrombosis underwent independent assessment by means of ultrasonography of the proximal veins, a whole-blood D-dimer assay, and a pretest clinical model. Patients with normal ultrasonographic findings and an abnormal D-dimer assay result were scheduled for repeated ultrasonography. We evaluated the incidence of symptomatic venous thromboembolic complications during a 3-month follow-up, and the value of clinical pretest probability with ultrasonography or D-dimer assay in scenario analyses. RESULTS: We studied 1756 patients with prevalence of thrombosis of 22%. At entry, results of the D-dimer assay and ultrasonography were normal in 828 patients (47%). Of these, 6 returned with confirmed symptomatic venous thromboembolism (complication rate, 0.7%; 95% confidence interval [CI], 0.3%-1.6%). Repeated ultrasonography was avoided in 61% of the patients with an initial normal test result. Scenario analyses disclosed that the complication rate was 1.6% (95% CI, 0.8%-2.6%) in those with a low clinical pretest probability and a normal result of ultrasonography at referral, whereas this figure was 1.8% (95% CI, 0.9%-3.3%) in patients with a low clinical probability result and a normal result of the D-dimer assay at referral. CONCLUSIONS: It is safe to withhold repeated ultrasonography in patients with suspected deep vein thrombosis who have normal results of ultrasonograpy and the SimpliRED D-dimer assay at presentation. The combination of a low clinical pretest probability with a normal result of compression ultrasonography or the D-dimer assay appears to be equally safe in refuting the diagnosis of deep vein thrombosis.

Twin pregnancy following endoluminal exclusion of an iliac arteriovenous fistula.

PURPOSE: To demonstrate the sustained efficacy of stent-graft exclusion of a pelvic arteriovenous fistula (AVF) in a woman who became pregnant after treatment. CASE REPORT: An iatrogenic iliac arteriovenous fistula caused by redo surgery for a herniated disk in a 23-year-old woman was successfully treated with percutaneous endoluminal exclusion. Intravascular ultrasound was particularly useful for localization of the fistula during the procedure. The patient subsequently became pregnant, and serial Doppler studies were used to monitor the stent-graft until the uneventful delivery of twins by Caesarian section. At 36 months after endograft implantation, the patient has no complaints relative to the device. CONCLUSIONS: Uncomplicated twin pregnancy following stent-graft repair of an AVF in the pelvis appears feasible.

High versus low doses of unfractionated heparin for the treatment of superficial thrombophlebitis of the leg. A prospective, controlled, randomized study.

BACKGROUND AND OBJECTIVES: The optimal treatment of superficial thrombophlebitis of the leg is undefined. The main study objective was to assess the efficacy and safety of unmonitored high doses as compared to low doses of unfractionated heparin (UFH) for prevention of venous thromboembolic complications in patients with superficial thrombophlebitis of the thigh. DESIGN AND METHODS: Sixty consecutive patients with acute thrombophlebitis of the great saphenous vein, as assessed by ultrasonography, were randomized to subcutaneous injection twice daily of UFH in high unmonitored doses (12,500 IU for one week followed by 10,000 IU) or prophylactic doses (5,000 IU) for four weeks. The rate of asymptomatic involvement of the deep venous system and/or symptomatic thromboembolic events during a six-month follow-up period was assessed and compared between the two study groups. RESULTS: Six of the 30 patients (20.0 %; 95% CI, 7.7 to 38.6) randomized to low-dose UFH developed symptomatic or asymptomatic events as compared to 1 of the 30 patients (3.3%; 95% CI, 0.07 to 17.2) who received high-dose UFH (p=0.05 by one-sided Fisher's exact test). No patient experienced major bleeding complications in either group. INTERPRETATION AND CONCLUSIONS: The results of this study suggest that in patients with acute thrombophlebitis of the thigh unmonitored high doses of UFH are more effective than prophylactic doses of UFH for prevention of venous thromboembolic complications and do not enhance the risk of bleeding complications.