Preventing Pulmonary Embolism After Joint Replacement

In August, MUSC was awarded $13.5 million by the Patient-Centered Outcomes Research Institute (PCORI) to conduct a 25-site trial enrolling 25,000 patients that will answer a long-standing clinical question: what is the best approach to anticoagulation after hip or knee replacement to prevent pulmonary embolism (PE)? Vincent Pellegrini, M.D., Chair of the Department of Orthopaedics, is the principal investigator for the trial.

In rare cases (1 in 1000), patients who undergo hip or knee replacement die as a result of PE. To prevent this, standard practice is to administer an anticoagulant for 35 days after surgery. Many new drugs touting higher efficacy at preventing clots have been approved in recent years, but these typically have a bleeding/hematoma risk of 3 percent to 5 percent. Such bleeding episodes can lead to infection, delayed wound healing, reoperation, compromised function of the joint, and implant removal.

Whether the added protection against clots offered by these newer agents outweighs the risk of bleeding is unknown, because the cost of conducting a clinical trial enrolling enough patients to reach statistical significance has been prohibitive. The PCORI funding mechanism was created to address just such gaps in the evidence that leave physicians and their patients without clear answers to clinical questions.

The trial will randomize patients to one of three treatment arms—aspirin, warfarin, or rivaroxaban (Xarelto®; Bayer Aktienges- ellschaft)—representing the full spectrum of currently available approaches, from the most conservative to the most aggressive. Its results should provide a definitive answer to whether the additional protection against clots provided by the new agents outweighs the risk of increased bleeding and will have immediate relevance to patient care.

MUSC Health will serve as the lead site, acting as the clinical coordinating center and hosting the central Institutional Review Board. Leslie (Les) A. Lenert, M.D., MS, SmartState Endowed Chair in Medical Bioinformatics, will sit on the central patient advisory board to assist in assessing patient preference and risk tolerance for use of anticoagulants after joint replacement.