Sent 6-20-07 Re: R Alikhan, AT Cohen. Heparin for prevention of venous thromboembolism in general medical patients (excluding stroke and MI). DOI: 10.1002/14651858. Cochrane Database of Systematic Reviews 2002:Art. No.: CD003747. (Protocol)
The efficacy of pharmacological thromboprophylaxis of surgical patients
is based on relatively small trials (mostly < 5000 subjects) and use the
surrogate endpoints of venograms and noninvasive leg vein clot studies that
find mostly transient asymptomatic thromboses. None show a statistically
significant reduction in fatal PE due to anticoagulant prophylaxis. However,
Goldhaber and colleagues tracked the incidence of developing DVT or PE after
hospitalization in about 80,000 patients admitted over a two year period in the Brigham and Women’s
Hospital. Out of 13 deaths due to PE that occurred in these patients, 12 had
received anticoagulant prophylaxis.1 This translates to an
estimated increased PE death rate of
over 20 fold.2
Note an undisclosed financial conflict of interest. As a member of the PEGASUS investigators and ARTEMIS investigators, A.T. Cohen conducted fondaparinux trials funded by NV Organon and Sanofi-Synthelabo and GlaxoSmithKline and has been a consultant for these anticoagulant producing companies.3, 4
1. Goldhaber SZ, Dunn K, MacDougall RC. New Onset of Venous Thromboembolism Among Hospitalized Patients at Brigham and Women’s Hospital Is Caused More Often by Prophylaxis Failure Than by Withholding Treatment. Chest. 2000;118:1680-1684.
2. Cundiff DK. Reply to Letters re Anticoagulation Therapy for Venous Thromboembolism. Medscape General Medicine. January 3, 2005;6(4):http://www.medscape.com/viewarticle/496149.
3. Agnelli G, Bergqvist D, Cohen AT, Gallus AS, Gent M. Randomized clinical trial of postoperative fondaparinux versus perioperative dalteparin for prevention of venous thromboembolism in high-risk abdominal surgery. PEGASUS investigators. Br J Surg. 2005;92(10):1212-1220.
4. Cohen AT, Davidson BL, Gallus AS, et al. Efficacy and safety of fondaparinux for the prevention of venous thromboembolism in older acute medical patients: randomised placebo controlled trial. 10.1136/bmj.38733.466748.7C. BMJ. February 11, 2006;332(7537):325-329.