utility of CHADS2VASc score in non valvular AF with evidence supporting in various trial

1. CHADS2 VASc SCORE
DR MAHENDRA
CARDIOLOGY,JIPMER

2. introduction
• Atrial fibrillation confers an excess risk of stroke.
• stroke risk depends on the presence or absence of various risk factors.
• anticoagulant therapy reduces the risk of stroke and all cause mortality.
• clinical guidelines recommend stroke thromboprophylaxis among AF pts unless
they are at low risk.
• patients with low risk are defined as those with age <65 years and lone AF.

3. Why Is It Important to Risk Stratify AF Patients?
• current treatment practice for stroke prevention in eligible AF patients revealed ongoing underuse of
OAC treatment
• <70% of eligible patients receiving OAC particularly among those patients at highest risk.
• high-risk AF patients before admission for stroke revealed that 29% of patients were not receiving
any antithrombotic therapy,
• 31% were prescribed antiplatelet therapy,
• only about one quarter of the 39% receiving warfarin (10%) achieved therapeutic international
normalized ratio levels.
• Overestimation of the risk of bleeding by physicians is a key barrier to OAC prescription.
• a systematic review. Am J Med. 2010; 123: 638–645

5. • widely used CHADS2 score-
• Congestive Heart Failure =1
• Hypertension=1
• Age ≥75 Years=1
• Diabetes Mellitus=1
• Stroke/TIA =2
• scores range from 0 to 6
• derived from the risk factors obtained from the original data sets from the AF
Investigators and the Stroke Prevention in AF trial.

6. Limitation of CHADS2 score
• not include many common potential stroke risk factors.
• classified as-
• score of 0 as low risk
• 1–2 as moderate/intermediate risk
• ≥ 3 as high risk.
• previous stroke or TIA alone as a risk factor categorized as moderate risk using the
original categorization despite this highest risk for subsequent stroke or
thromboembolism.
• poor predictive value for the CHADS2 schema (c statistics approximately 0.6)
• its original validation would categorise nearly 60%– 65% of various AF populations into
the moderate/intermediate risk category.
• Physician confusion about use of asprin or warfarin in CHADS2 score 1

7. How CHADS2VASc score come in picture
• 1. new trial data supporting the importance of less well validated risk factors
for stroke
• female sex
• age of 65 to 74 years
• vascular disease
• 2. benefit of OAC over aspirin in stroke reduction and mortality, even in patients
at so-called moderate risk (eg, CHADS2 score of 1).
• 3. benefit of aspirin for stroke prophylaxis in AF has been questioned.
• European Heart Journal (2012) 33, 1500–1510

8. • The latest (2012) focused update of the ESC Guidelines for the management of
AF again recommended the CHA2DS2-VASc score to assess the stroke-risk of non-
valvular AF patients (IA), particularly to identify the truly low-stroke-risk patients.

9. categories of 0 = low risk, 1 = intermediate risk,
and ≥ 2 as high risk
• CHA2DS2-VASc score to complement the CHADS2 scheme.

10. • CHA2DS2-VASc scheme tries to formalise female gender, age 65–74, and vascular
disease risk factors in an attempt to become more inclusive of common stroke
risk factors in AF.
• CHA2DS2-VASc is good at identifying truly low risk patients with AF (≤ 1%/year,
with a CHA2DS2- VASc score = 0),
• categorised the lowest proportion into the moderate/intermediate risk strata.
• point estimate using the c-statistic was marginally better than the CHADS2
schema.

21. 2016 ESC Guidelines for the management of atrial
fibrillation

22. Stroke prevention therapy in atrial fibrillation
patients

25. conclusion
• CHADS2VASc is validated score for estimation of stroke risk.
• More useful in differentiating low risk patients.
• 0(male),1(female)does not require any anticoagulation therapy.
• NOAC is preferred treatment as comparison to VKA.
• Combination of anticoagulant and antiplatelet should be avoided.
• Aspirin has no role in new European guideline for stroke prevention.
• Emerging risk score is ATRIA stroke risk score.

26. THANK YOU