Certain risk factors may increase the risk of stroke in patients with atrial fibrillation.


Risk factors:

(1) age of the patient

(2) concurrent conditions

(3) past medical history


Age of Patient

Concurrent Condition(s)

Risk (annual risk without anticoagulation)

< 65 years of age


low (annual risk 1%)

< 65 years of age

hypertension or diabetes

medium (annual risk 4%)

> 65 years of age



>= 75 years of age

hypertension or diabetes

high (annual risk 8%)


history of transient ischemic attack or cerebrovascular accident

high (annual rate 12%)


large left atrium; impaired left ventricular function; intracardiac thrombus; valvular lesions; calcifications of the mitral valve




• The risk for the age interval of 65-74 with hypertension or diabetes is not explicit in the table. In the implementation these will be indicated as medium risk.


To read more or access our algorithms and calculators, please log in or register.