Prophylactic Dose of Rivaroxaban Versus Warfarin for the Treatment of Isolated Calf Muscle Vein Thrombosis: A Retrospective Propensity Score-Matched Analysis.

BACKGROUND: Prophylactic dose of rivaroxaban is often used in treatment of isolated calf muscle vein thrombosis (ICMVT); nevertheless, its effect is less reported. This study aims to evaluate short-term outcomes in patients with ICMVT who received prophylactic dose of rivaroxaban or warfarin therapy. METHODS: A retrospective analysis of 472 ICMVT patients who received 2 different treatment regimens was undertaken. Propensity score matching method was used to balance the confounding effect of baseline clinical data. Chi-squared test and logistic regression analysis were used to compare outcomes (venous thromboembolism events, bleeding events, complete clot resolution) according to the type of treatment regimens before and after propensity score matching. Univariate and multivariable analysis were used to investigate risk factors for incomplete clot resolution of ICMVT after propensity score matching. RESULTS: 242 ICMVT patients received prophylactic dose of rivaroxaban (rivaroxaban group, RG), and 230 received warfarin (warfarin group, WG). After propensity score matching, 156 patients were included in each group; Venous thromboembolism (VTE) events occurred in 14 (9.0%) patients in the RG and 10 (6.4%) in the WG (P = 0.395); no major bleeding events occurred in each group, and clinically relevant nonmajor bleeding events occurred in 5 (3.2%) patients in the RG and 10 (6.4%) in the WG (P = 0.186); complete clot resolution at 3 months occurred in 80 (51.3%) patients in the RG and 100 (64.1%) in the WG (P = 0.022). Logistic regression analysis showed that there were no significant differences between RG and WG in VTE events (odds ratio 1.439, 95% confidence interval 0.619-3.347, P = 0.397) and clinically relevant nonmajor bleeding events (odds ratio 0.483, 95% confidence interval 0.161-1.449, P = 0.194); it revealed that complete clot resolution rate at 3 months was different in the 2 groups (odds ratio 0.589, 95% confidence interval 0.375-0.928, P = 0.022). Treatment regimens (prophylactic dose of rivaroxaban), thrombosis (maximum diameter >7 mm), and risk factors for VTE (nonsurgery risk factors, mainly referring to active malignancy) were risk factors for incomplete clot resolution of ICMVT (P < 0.05). CONCLUSIONS: In this retrospective study with a short-term follow-up, ICMVT patients who received prophylactic dose of rivaroxaban had no significant differences in VTE and bleeding events compared to those who received warfarin therapy (the overall INR >2.0 for >50% of the time); but it was not conducive to complete clot resolution.

Metformin inhibits high glucose-induced smooth muscle cell proliferation and migration.

We investigated the protective effects and mechanism of action of metformin on high glucose-induced smooth muscle cell proliferation and migration. Vascular smooth muscle cells (VSMCs) were subjected to a series of concentrations (0-10 mM) of metformin. CCK-8, wound healing, and transwell assays were performed. Correlations between metformin concentration and high-mobility group box 1 (HMGB1) and miR-142-3p levels were assessed. In addition, miR-142-3p mimic and siRNA were used to investigate VSMC migration in the presence or absence of metformin. In the high-glucose condition, metformin decreased cell growth and inhibited cell migration. HMGB1 gene expression correlated negatively with metformin concentration, whereas miR-142-3p expression correlated positively with metformin concentration. In addition, mimic-induced miR-142-3p elevation resulted in decreased HMGB1 and LC3II levels and elevated p62 levels in the high-glucose condition, whereas miR-142-3p knockdown had the reverse effects, and metformin abolished those effects. Metformin inhibits high glucose-induced VSMC hyperproliferation and increased migration by inducing miR-142-3p-mediated inhibition of HMGB1 expression via the HMGB1-autophagy related pathway.

Metformin inhibits angiogenesis of endothelial progenitor cells via miR-221-mediated p27 expression and autophagy.

Aim: To explore the underlying mechanisms of metformin on the angiogenic capacity of endothelial progenitor cells (EPCs). Results: EPC growth and miR-221 expression decreased concentration-dependence with metformin, and a negative correlation was observed between miR-221 expression and metformin concentration (p < 0.001). miR-221 overexpression using a mimic decreased the metformin-mediated angiogenic effects in EPCs (p < 0.01). Metformin increased p27 and LC3II expression and AMP-activated protein kinase (AMPK) phosphorylation, and decreased p62 expression, while miR-221 overexpression reversed the effects of metformin. Additionally, AMPK inhibition by compound C reversed the increase in p27 and LC3II levels and AMPK phosphorylation or miR-221 siRNA treatment. Conclusion: Metformin inhibits the angiogenic capacity of EPCs. The underlying mechanism involves AMPK-mediated autophagy pathway activity and increases miR-221-mediated p27 expression.

Incidence and risk factors of early deep venous thrombosis after varicose vein surgery with routine use of a tourniquet.

INTRODUCTION: The incidence of early deep venous thrombosis (DVT) following varicose vein surgery (traditional open stripping) with routine use of a tourniquet remains unknown. MATERIALS AND METHODS: A retrospective analysis of all patients who underwent varicose vein surgery with a tourniquet in the authors' unit between 1 January 2012 and 30 November 2013 was undertaken. Cases of postoperative DVT were identified from the unit database, and re-assessments conducted 1, 3 and 6 months after the initial diagnosis were recorded from the outpatient department. RESULTS: Out of 1461 patients, 113 (7.7%) developed postoperative DVT. Nineteen (1.3%) patients had proximal DVT, and 94 (6.4%) patients had isolated distal DVT. The risk factors for postoperative DVT included old age (≥65 years), female sex and gastrocnemius vein dilation (GVD). GVD was found to be a significant independent risk factor for the occurrence of DVT, with an odds ratio of 2.437 (95% confidence interval 1.644-3.611). Five patients with distal DVT (5.7%) and eight patients with proximal DVT (44.4%) still exhibited a thrombus at 6-month follow-up, but with decreased size and at various stages of resolution. CONCLUSIONS: This study found a higher incidence of postoperative DVT (7.7%) with routine use of a tourniquet during varicose vein surgery than has been reported previously. Among the factors examined, GVD had the highest predictive power for postoperative DVT. Both distal and proximal DVT were associated with acceptable outcomes.