CHADS2 Score

Congestive Heart Failure

Hypertension

Age >= 75

Diabetes

Prior Stroke/TIA (2 points)

CHADS2 Score: 0 — Annual stroke risk: 1.9%

Low Risk

A score of 0 is associated with the lowest annual risk of stroke; anticoagulation is often not recommended on CHADS2 alone.

How this is calculated

A point-per-risk-factor clinical score (heart failure, hypertension, age ≥75, diabetes = 1 each; prior stroke/TIA = 2) validated to stratify annual stroke risk in atrial fibrillation. The published per-score stroke rates come from the original validation study.