Novel Oral Anticoagulants in Cardiovascular Disease

Abstract

Nonvalvular atrial fibrillation (AF) confers an increased risk of thromboembolism, with a 5-fold higher risk of ischemic stroke. Oral anticoagulation (OAC) has shown to be highly effective in preventing stroke and mortality compared to placebo and is also used in patients without AF for both treatment and prophylaxis of venous thromboembolism. The OAC halts the coagulation by different mechanisms. Until recently, the only option was the vitamin K antagonists (VKAs), but their inherent limitations have promoted the development of novel oral anticoagulants (NOACs), which may offer efficacious and safer alternatives. Patients should be carefully selected to receive the most suitable treatment for each one. As the VKA efficacy and safety largely rely on the time the patient remains within the therapeutic range, this could be a useful selection criterion. Bleeding remains the main complication of all OACs. Although clinical trials of stroke prevention in AF have shown a significant reduction in hemorrhagic stroke and intracranial bleeding with the NOACs, as prescriptions are increasing, clinicians need to be prepared to accurate management of bleeding complications. Withholding the drug is usually enough for most cases of mild bleeding, but in patients with major, life-threatening bleeding, other measures, such as fluid replacement and blood transfusion, might be necessary while waiting for specific reversal agents that may reach the market soon. In case of acute bleeding, the accurate estimation of anticoagulant effect could also be needed, but the currently available coagulation tests only offer a qualitative measure. While awaiting long-term safety data, the choice between all these available therapies should be based on patient preferences, compliance, and ease of administration as well as on local factors affecting cost-effectiveness. But the increasing variety of therapeutic options when chronic OAC is needed can only improve the provided health care.