Many studies suggest a higher incidence of thromboembolic syndromes such as stroke, peripheral arterial thrombosis and pulmonary embolism in patients with heart failure (HF), particularly those with left ventricular systolic dysfunction. As a result, some clinicians have chosen to treat patients with HF with anticoagulants as primary prevention against thromboembolic events. However, this practice is not well-supported by scientific data. Retrospective analyses of large HF trials have yielded contradictory results and randomised trials designed to specifically address this question have been under-populated and under-powered. As a result, there is no general consensus among professional societies in either recommending or advising against anticoagulants in HF. We hope that ongoing clinical trials, WARCEF in particular, will yield results that will guide clinicians in deciding for or against routine use of anticoagulants in HF.