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.