Risk stratification | Low (annual stroke risk <5%) | High (annual stroke risk >10%) | |
VTE | Based on the time interval from the VTE event | DVT or PE: >12 months and no other risks | DVT or PE: <3 months or severe thrombophilia |
Mechanical heart valve | Based on position, number and type of valves | Bicuspid aortic valve without atrial fibrillation or other risks for stroke | Mitral valve, aortic valve with risk factors for stroke |
Atrial fibrillation# | Based on CHADS₂ score | CHADS₂ score 0–2 | CHADS₂ score 5–6 |
VTE: venous thromboembolism; DVT: deep vein thrombosis; PE: pulmonary embolism. #: moderate risk; recommendation is to individualise each case and have a risk–benefit discussion with the patient.