Also, I noticed from the Vienna study that ...."...low dose low molecular weight heparin was given...with similar dosing in both groups..."
While it states the heparin given was 'low dose', I believe the Leo trial precludes the use heparin because it interacts with antithrombin. I don't have any insight about how much heparin required to impair the antithrombin but even a small amount might well affect the result.