A means of predicting the likelihood that a patient in atrial fibrillation will have a stroke. CHADS is a mnemonic for c(ongestive) heart failure; h(ypertension), a(ge) over 75 years, d(iabetes) mellitus, and a previous history of s(troke) (or transient ischemic attack [TIA]).

PATIENT CARE
A previous history of stroke or TIA is worth two points. The other variables are each worth one point. Patients with a CHADS score of 0 can be safely treated with aspirin because they have the lowest probability of stroke. Patients with one point can be treated either with aspirin or warfarin. Patients who score two or more points should be treated with warfarin as the preferred stroke prevention unless there are contraindications to the drug.