Clinical Indications for Direct Acting Oral Anticoagulants

Abstract

Oral anticoagulation is the mainstay of therapy for the prevention and treatment of arterial and venous thrombosis. Landmark trials in the last decade have demonstrated the superior safety of direct acting oral anticoagulants (DOACs) in patients with nonvalvular atrial fibrillation. In addition, these trials suggested superior efficacy when using apixaban or dabigatran. This led to the preferential use of DOACs as first-line therapy in nonvalvular atrial fibrillation. Similarly, superior safety observed in landmark trials of venous thromboembolism has resulted in a first-line preferential recommendation for DOACs. Recently, randomized trial data has shown that low-dose rivaroxaban decreases cardiovascular events in patients with stable coronary artery disease though this comes at a risk of increased bleeding. Such a benefit has not been clearly shown in those with acute coronary syndrome. Observational data has suggested that DOACs are noninferior to warfarin for treatment of left ventricular thrombus and stroke prevention in rheumatic mitral valve disease. Large, randomized trials are clearly needed to inform anticoagulation selection in these populations. Two areas in which data has been more definitive are heart failure with sinus rhythm and embolic stroke of unknown source. Trials in these areas have shown that the addition of DOACs does not provide any benefit but leads to increased bleeding events. Finally, in those with mechanical heart valves and left ventricular assist devices, the use of DOACs has been shown to be harmful, albeit with very limited data, and is therefore contraindicated.