Unanswered questions in venous thromboembolism.

We have made great strides in the diagnosis, treatment and prevention of venous thromboembolism (VTE). Despite these advances, however, questions remain. Perhaps the most important unmet need is the development and implementation of strategies to increase the uptake of guidelines for thromboprophylaxis. VTE is largely preventable with appropriate prophylaxis. New oral anticoagulants have the potential to further streamline VTE prevention and treatment. Although heparin, low molecular weight heparins or fondaparinux are frequently used for thromboprophylaxis in hospitalized medical or surgical patients, these agents are not ideal for out-of-hospital use. There is now good evidence that patients undergoing major orthopaedic surgery require extended thromboprophylaxis. Medical patients may also benefit from extended prophylaxis. The new oral anticoagulants will be more convenient than existing agents for this purpose and will help physicians and patients to adhere to optimal preventive strategies. VTE treatment also may be simplified with the new oral anticoagulants. With a rapid onset of action, these drugs may obviate the need for a parenteral anticoagulant for initial therapy. In addition, the new agents have the potential to streamline extended VTE therapy because, unlike vitamin K antagonists, they can be given in fixed doses without the need for coagulation monitoring.