VIsceral Fat Reduction Assessed by CT-scan On RImonabAnt

Primary objective: To assess the effect of rimonabant on visceral fat area over a period of 12 months when prescribed with a mild hypocaloric diet in abdominally obese patients with metabolic syndrome Secondary objectives: * To assess the effect of rimonabant over a period of 12 months on: * Liver fat content using CT scan (Computed Tomography scan) * Anthropometric measures (weight, waist circumference, body composition using Dual Energy X-ray Absorptiometry (DEXA)) * Lipid, lipoprotein profile * Glycemia, insulinemia and HbA1c * Adipokines, inflammatory and hemostatic markers * To evaluate the percentage of patients with metabolic syndrome at 12 months * To evaluate the safety and tolerability of rimonabant in these patients In four selected US sites the effect of rimonabant at 12 months will be also assessed on: * Basal lipolysis and insulin suppressed lipolysis (euglycemic hyperinsulinemic clamp). * Resting metabolic rate and substrate oxidation at rest using indirect calorimetry. * Adipose tissue histology and expression of genes involved in glucose and lipid metabolism (superficial adipose tissue biopsy).