Efficacy of two micronized purified flavonoid fraction dosing regimens in the pelvic venous pain relief

Background: The venoactive drug treatment regimen for pelvic venous disorders (PeVDs) is not finally established. The study aimed at assessing the efficacy of micronized purified flavonoid fraction (MPFF) in a standard or double dose in the pelvic venous pain (PVP) relief in PeVD. Methods: We analyzed the treatment efficacy in 125 female patients with PeVD, who were allocated to two groups with MPFF treatment in a regular dose of 1000 mg once daily (OD) for 2 months (N.=65; group 1) or double dose of 1000 mg twice daily for 1 month and then 1000 mg OD for 1 month (N.=60; group 2). Patients underwent clinical examination along with an assessment of the PVP severity using the visual analogue scale (VAS) ranged from 0 to 10 scores, transvaginal and transabdominal duplex ultrasound scanning (DUS), and single-photon emission computed tomography (SPECT) of the pelvic veins with in vivo-labelled red blood cells (RBCs). The groups were different at baseline in the PVP severity (3.4 +/- 1.2 vs. 7.3 +/- 0.5 scores in groups 1 and 2, accordingly; P=0.012). DUS and SPECT were used to evaluate diameters of gonadal, parametrial, and uterine veins, to assess the presence of reflux in them, to measure blood flow velocity in the internal iliac veins (V-lin (IIV)), and to calculate the coefficient of pelvic venous congestion (C-PVC). Results: The treatment was associated with a significant reduction in the PVP score from 3.4 +/- 1.2 to 1.2 +/- 0.2 (P=0.03) when using the standard dose for 2 months and from 7.3 +/- 0.5 to 0.8 +/- 0.1 (P=0.001) when using the double dose in the 1st month. The PVP relief was achieved on average after 13.7 +/- 0.6 and 3.1 +/- 0.8 days in groups 1 and 2, accordingly (P=0.0001 between the groups). At month 2, the C-PVC reduction was found to be significantly greater in group 2 compared to group 1 (46.6% vs. 25%; P=0.018). Side effects (gastralgia, flatulence) were reported by only 2 (3.3%) patients of group 2. Conclusions: The venoactive drug therapy with MPFF is an effective and safe option for the PVP relief in female patients with PeVD. The use of double dose in the 1st month seems to be appropriate in patients with greater PVP severity but is associated with an increased rate of side effects.