Low dose oral vitamin K to reverse acenocoumarol-induced coagulopathy: a randomized controlled trial.

Low dose oral vitamin K rapidly reverses warfarin-associated coagulopathy. Its effect in patients receiving acenocoumarol is uncertain. We compared the effect of withholding acenocoumarol and administering 1 mg oral vitamin K with simply withholding acenocoumarol in asymptomatic patients presenting with INR values between 4.5 and 10.0. The primary end-point of the study was the INR value on the day following randomisation. We found that patients receiving oral vitamin K had more sub-therapeutic INR levels than controls (36.6% and 13.3%, respectively; RR 1.83, 95% confidence interval 1.16, 2.89) and a lower, but non-significant, proportion of INR values in range (50% and 66.6%, respectively) on the day following randomisation. After 5 +/- 1 days, there were more patients with an INR value in range in the vitamin K group than in controls (74.1% and 44.8%, respectively). There were no clinical events during 1 month follow-up. We conclude that the omission of a single dose of acenocoumarol is associated with an effective reduction of the INR in asymptomatic patients presenting with an INR value of 4.5 to 10.0. Furthermore, the use of a 1 mg dose of oral vitamin K results in an excessive risk of over-reversal of the INR.

Predictors of residual venous obstruction after deep vein thrombosis of the lower limbs: a prospective cohort study.

INTRODUCTION: Delayed thrombus regression after deep vein thrombosis (DVT) of the lower limbs is associated with increased risk of DVT recurrence. Predictors of residual venous occlusion are unknown. We hypothesized that obesity, which causes reduced fibrinolytic activity, can predict delayed thrombus regression. MATERIALS AND METHODS: In a prospective cohort study, 98 patients with objective diagnosis of DVT underwent compression ultrasonography (CUS) after 6 and 12 months. Persistent occlusion was arbitrarily defined as a thrombus occupying, at maximal point of compressibility, more than 20% of the vein area in the absence of compression. The body mass index (BMI) and waist circumference were measured at baseline and at follow up to assess individual patterns of body fat distribution. Information on antithrombotic treatment, family history of varicose veins, cigarette smoking, concomitant disorders, the presence of known risk factors for DVT, the duration of anticoagulant treatment and the use of elastic stockings was collected. RESULTS: Post-thrombotic recanalization was documented in 34 patients (34.7%) at 6 months and in 44 patients (44.9%) at 12 months. There was no difference in the mean BMI (p=0.469 at 12 months), in the prevalence of obesity (p=0.479) and visceral pattern of body fat distribution (p=0.239) between patients who did and did not show thrombus regression. The presence of a permanent risk factor for DVT was the only predictor of delayed thrombus regression (OR 11.0, 95% CI 1.359-61.978). CONCLUSIONS: Despite consistent evidence of impaired fibrinolysis, obesity is not associated with persistent venous obstruction.

Atrial fibrillation and antithrombotic treatment in Italian hospitalized patients: a prospective, observational study.

BACKGROUND: We studied the prevalence of atrial fibrillation within a large Italian inpatient population, and evaluated the use of antithrombotic therapy among these individuals. METHODS: A prospective cross sectional study (Phase 1) with a 1-year follow-up period (Phase 2) was conducted at a single Italian centre. During Phase 1, we conducted a chart review of all inpatients on 5 separate days, each 1 month apart, between January and May 1999. During Phase 2, at 1-year of follow-up, patients or their families were contacted to document the occurrence of new clinical events, as well as current antithrombotic therapy use. RESULTS: A total of 3121 patient charts were reviewed. The prevalence of atrial fibrillation was 7.2%. Of these 224 patients, 21.3% were on oral anticoagulants, 29.7% on antiplatelets, while 49% received neither. Patients on oral anticoagulants were significantly younger (mean age 72.3 years) than those on antiplatelets (mean age 80.6 years; p<0.001) or neither therapy (mean age 80.7 years; p<0.001). At 1 year follow up, an acute ischaemic stroke occurred among 7.4% of the 121 contacted patients. Among patients with chronic atrial fibrillation [98], 25.5% were receiving an oral anticoagulant. CONCLUSIONS: Despite clear evidence from clinical trials, oral anticoagulants are significantly underused among patients with chronic atrial fibrillation. Methods should be developed to improve both physician and patient knowledge about the overall benefits of anti-thrombotic therapy among these individuals.

[Auditory evoked potentials and magnetic resonance in the diagnosis and follow-up of central pontine myelinolysis]. / Potenciales evocados auditivos y resonancia magnética en el diagnóstico y seguimiento de la mielinolisis central pontina.

We report the case of a woman who developed central pontine myelinolysis in spite of gradual correction of hyponatremia. The good clinical evolution as well as the influence of rapid correction of serum sodium concentration in the unfolding of this rare condition are discussed. Several diagnostic procedures, mainly auditory-evoked responses and magnetic resonance imaging are also analysed. We remark the particular interest of the auditory-evoked responses in the attestation of an eventual remyelination.