The CHADS₂ Score: A Tool for Assessing Stroke Risk in Patients with Atrial Fibrillation

What is the CHADS₂ Score?

The CHADS₂ score is a clinical tool used to assess the risk of stroke in patients with atrial fibrillation (AF). It is a simple and easy-to-use score that is based on five clinical factors:

• Congestive heart failure
• Hypertension
• Age ≥75 years
• Diabetes
• Stroke or transient ischemic attack (TIA)

How is the CHADS₂ Score Calculated?

Each of the five clinical factors is assigned a point value:

• Congestive heart failure: 1 point
• Hypertension: 1 point
• Age ≥75 years: 1 point
• Diabetes: 1 point
• Stroke or TIA: 2 points

The total CHADS₂ score is the sum of the points for each of the five factors.

How is the CHADS₂ Score Used?

The CHADS₂ score is used to stratify patients with AF into different risk categories for stroke:

• Low risk (CHADS₂ score of 0): Less than 1% annual risk of stroke
• Moderate risk (CHADS₂ score of 1): 1-2% annual risk of stroke
• High risk (CHADS₂ score of ≥2): >2% annual risk of stroke

The CHADS₂ score is used to guide decisions about whether to start anticoagulation therapy to prevent stroke in patients with AF.

Limitations of the CHADS₂ Score

The CHADS₂ score is a simple and easy-to-use tool, but it has some limitations:

• It does not include all of the risk factors for stroke in patients with AF, such as left atrial size and smoking.
• It is not as accurate as some other risk assessment tools, such as the CHA₂DS₂-VASc score.

Conclusion

The CHADS₂ score is a useful tool for assessing the risk of stroke in patients with AF. It is simple and easy to use, but it has some limitations. The CHADS₂ score should be used in conjunction with other risk factors to make decisions about whether to start anticoagulation therapy to prevent stroke in patients with AF.