|Title:||Comparison of the CHADS2 score and ESC guidelines for prevention of thromboembolism in patients with atrial fibrillation|
|Evaluation Topic:||24.00 - Prevention of CVD|
|On Behalf of:|
|JR. Vyselaar1, M. Matangi2 - (1) Queen's University, Kingston, Canada (2) Kingston Heart Clinic, Kingston, Canada|
PURPOSE. The CHADS2 score for initiation of either Aspirin or Warfarin therapy in patients with either paroxysmal, persistent or permanent atrial fibrillation (PAF) is a very simple clinical tool. There is a good correlation between increasing CHADS2 score and the future risk of thromboembolic events. CHADS2 gives a score of 1 each for CHF, hypertension, Age >75 years and diabetes with 2 points for stroke or TIA. To date we have been using the ESC guidelines for either Aspirin or Warfarin therapy in patients with PAF. The purpose of this analysis was to compare the ESC guideline driven therapy with the more simple CHADS2 score by retrospectively calculating the CHADS2 score on all patients in our cardiology database, CARDIOfile with a diagnosis of PAF.
METHODS. 467 patients were identified with a diagnosis of PAF. 26 were excluded because of either mitral stenosis (n=1) or a mechanical heart valve (n=25). These patients require Warfarin but are not accounted for in the CHADS2 score. The remaining 441 patients were used in this analysis. Any patient with PAF and either two ESC moderate risk factors or 1 ESC high risk factor is an indication for Warfarin. A single ESC moderate risk factor was considered an indication for either Aspirin or Warfarin. The absence of any ESC risk factor was considered an indication for Aspirin. A CHADS2 score of 2 or more is an indication for Warfarin. A CHADS2 score of 0 or 1 is an indication for Aspirin. All statistics were based on the ESC guidelines being the gold standard for the use of Warfarin or Aspirin. Calculations were made for sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy.
RESULTS. See table 1.
CONCLUSION. The CHADS2 score accurately predicts the ESC guideline recommendations for Aspirin or Warfarin use in patients presenting with PAF. Use of the simple CHADS2 score in clinical practice to determine the use of either Aspirin or Warfarin seems reasonable.