CHA2DS2-VASc risk factor based point scoring system for atrial fibrillation is meant for assessing the risk of thromboembolism in non-valvar atrial fibrillation. Major risk factors (previous stroke, TIA or systemic embolism and age 75 years or more) are given a score of two points while other clinically relevant non-major risk factors ( congestive heart failure or moderate to severe left ventricular systolic dysfunction [left ventricular ejection fraction of 40% or less], hypertension, diabetes mellitus, age between 65-74 years, female sex and vascular disease [prior myocardial infarction, peripheral artery disease or aortic plaque]) are given one point each.
Congestive heart failure / LV dysfunction : 1
Hypertension : 1
Age 75 or more : 2
Diabetes mellitus : 1
Stroke/TIA/thromboembolism : 2
Vascular disease : 1
Age 65-74 : 1
Sex category (female sex) : 1
Maximum score : 9
CHA2DS2-VASc score is an improvement from the CHADS2 score. The risk increases as the score increases from 0 to 9. In a study involving over 7300 patients stroke rate was 0 when the score was 0, though there was only one patient in that category. There were fourteen patients with a score of nine and they had stroke rate of 15.2%. Maximum number of patients scores of 3 and 4 with 1730 and 1718 patients in these categories. Score 3 had a stroke rate of 3.2% and score 4 had a stroke rate of 4% [Cited from Eur Heart J. 2010; 31: 2369-2429].