{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"cha2ds2-vasc-score"},"result":{"entity_type":"calculator","id":"cha2ds2-vasc-score","calculator_id":"cha2ds2-vasc-score","canonical_url":"https://tttkmbb.com/medical/cha2ds2-vasc-score","name":"CHA₂DS₂-VASc Score Calculator","title":"CHA₂DS₂-VASc Score Calculator – Stroke Risk in Atrial Fibrillation with Annual Risk (Lip 2010)","category":"medical","category_name":"Medical & Clinical","tool_name":"calculate_cha2ds2_vasc_score","featured_mcp_tool":false,"description":"Scores stroke risk in non-valvular atrial fibrillation from age, sex, heart failure, hypertension, diabetes, prior stroke/TIA and vascular disease, and reports the adjusted annual stroke rate from the Euro Heart Survey (Lip 2010) plus the sex-free CHA₂DS₂-VA score.","use_when":"You need the CHA₂DS₂-VASc (or CHA₂DS₂-VA) score and the associated published annual stroke risk for a person with atrial fibrillation.","do_not_use_when":"The atrial fibrillation is valvular (moderate-to-severe mitral stenosis or mechanical valve), where anticoagulation is indicated regardless of score, or for bleeding risk (HAS-BLED is a different score).","inputs":[{"name":"age_years","label":"Age","type":"number","unit":"years","required":true,"min":18,"max":120,"description":"Age in years (65–74 scores 1, 75 and over scores 2).","example":70},{"name":"sex","label":"Sex","type":"enum","required":true,"values":[{"value":"male","label":"Male","aliases":["m","man"]},{"value":"female","label":"Female","aliases":["f","woman"]}],"description":"Sex (female scores 1 point in CHA₂DS₂-VASc).","example":"female"},{"name":"congestive_heart_failure","label":"Congestive heart failure / LV dysfunction","type":"boolean","required":false,"default":false,"description":"Clinical heart failure or reduced ejection fraction (1 point).","example":false},{"name":"hypertension","label":"Hypertension","type":"boolean","required":false,"default":false,"description":"Diagnosed hypertension or on treatment (1 point).","example":true},{"name":"diabetes","label":"Diabetes mellitus","type":"boolean","required":false,"default":false,"description":"Diabetes on diet or medication (1 point).","example":false},{"name":"stroke_tia_thromboembolism","label":"Prior stroke, TIA or thromboembolism","type":"boolean","required":false,"default":false,"description":"Any previous stroke, TIA or systemic embolism (2 points).","example":false},{"name":"vascular_disease","label":"Vascular disease","type":"boolean","required":false,"default":false,"description":"Prior myocardial infarction, peripheral artery disease or aortic plaque (1 point).","example":false}],"outputs":[{"name":"score","label":"CHA₂DS₂-VASc score","type":"integer","decimals":4,"description":"Total points, 0–9."},{"name":"cha2ds2_va_score","label":"CHA₂DS₂-VA score","type":"integer","decimals":4,"description":"Same score without the female-sex point (ESC 2024 variant), 0–8."},{"name":"annual_stroke_risk_percent","label":"Adjusted annual stroke rate","type":"number","unit":"%/year","decimals":1,"description":"Lip 2010 adjusted stroke/thromboembolism rate for the CHA₂DS₂-VASc score."},{"name":"risk_category","label":"Risk category","type":"string","decimals":4,"description":"Low (no non-sex risk factors), intermediate (one) or high (two or more)."},{"name":"components","label":"Points awarded","type":"string_list","decimals":4,"description":"Each criterion that contributed points."}],"input_schema":{"type":"object","properties":{"age_years":{"description":"Age in years (65–74 scores 1, 75 and over scores 2). Unit: years.","type":"number","minimum":18,"maximum":120,"examples":[70],"x-unit":"years"},"sex":{"description":"Sex (female scores 1 point in CHA₂DS₂-VASc).","type":"string","enum":["male","female"],"examples":["female"]},"congestive_heart_failure":{"description":"Clinical heart failure or reduced ejection fraction (1 point).","type":"boolean","default":false,"examples":[false]},"hypertension":{"description":"Diagnosed hypertension or on treatment (1 point).","type":"boolean","default":false,"examples":[true]},"diabetes":{"description":"Diabetes on diet or medication (1 point).","type":"boolean","default":false,"examples":[false]},"stroke_tia_thromboembolism":{"description":"Any previous stroke, TIA or systemic embolism (2 points).","type":"boolean","default":false,"examples":[false]},"vascular_disease":{"description":"Prior myocardial infarction, peripheral artery disease or aortic plaque (1 point).","type":"boolean","default":false,"examples":[false]}},"additionalProperties":false,"required":["age_years","sex"]},"output_schema":{"type":"object","properties":{"score":{"description":"Total points, 0–9.","type":"integer"},"cha2ds2_va_score":{"description":"Same score without the female-sex point (ESC 2024 variant), 0–8.","type":"integer"},"annual_stroke_risk_percent":{"description":"Lip 2010 adjusted stroke/thromboembolism rate for the CHA₂DS₂-VASc score. Unit: %/year.","type":"number","x-unit":"%/year"},"risk_category":{"description":"Low (no non-sex risk factors), intermediate (one) or high (two or more).","type":"string"},"components":{"description":"Each criterion that contributed points.","type":"array","items":{"type":"string"}}}},"formula":"score = CHF (1) + hypertension (1) + age ≥ 75 (2) + diabetes (1) + stroke/TIA/thromboembolism (2) + vascular disease (1) + age 65–74 (1) + female sex (1); annual risk from the Lip 2010 table: 0 → 0, 1 → 1.3, 2 → 2.2, 3 → 3.2, 4 → 4.0, 5 → 6.7, 6 → 9.8, 7 → 9.6, 8 → 6.7, 9 → 15.2 %/year","method":"The Lip 2010 rates are adjusted theoretical rates from 1,084 Euro Heart Survey patients not on anticoagulation; the non-monotonic values at scores 7–8 reflect small numbers, and later cohorts (Friberg 2012) give different absolute rates. Results are informational only and not a substitute for clinical judgement or medical advice.","sources":[{"name":"Lip GY et al. (2010) Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach: the Euro Heart Survey on atrial fibrillation, Chest 137:263-272","url":"https://pubmed.ncbi.nlm.nih.gov/19762550/","type":"peer_reviewed","retrieved_at":"2026-09-24"},{"name":"Wikipedia – CHA2DS2–VASc score","url":"https://en.wikipedia.org/wiki/CHA2DS2%E2%80%93VASc_score","type":"reference","retrieved_at":"2026-09-24"}],"freshness":{"type":"static","max_age_seconds":null,"note":"Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output."},"examples":[{"name":"70-year-old woman with hypertension","inputs":{"age_years":70,"sex":"female","hypertension":true},"expected":{"score":3,"cha2ds2_va_score":2,"annual_stroke_risk_percent":3.2,"risk_category":"High (2 or more non-sex risk factors)"},"url":"https://tttkmbb.com/api/v1/calculate/cha2ds2-vasc-score?age_years=70&sex=female&hypertension=true"},{"name":"80-year-old man with diabetes and prior stroke","inputs":{"age_years":80,"sex":"male","diabetes":true,"stroke_tia_thromboembolism":true},"expected":{"score":5,"annual_stroke_risk_percent":6.7,"risk_category":"High (2 or more non-sex risk factors)"},"url":"https://tttkmbb.com/api/v1/calculate/cha2ds2-vasc-score?age_years=80&sex=male&diabetes=true&stroke_tia_thromboembolism=true"},{"name":"50-year-old man, no risk factors","inputs":{"age_years":50,"sex":"male"},"expected":{"score":0,"annual_stroke_risk_percent":0,"risk_category":"Low (no non-sex risk factors)"},"url":"https://tttkmbb.com/api/v1/calculate/cha2ds2-vasc-score?age_years=50&sex=male"}],"faq":[{"q":"Why does female sex count?","a":"In the original cohorts women had higher stroke rates, but sex is a risk modifier rather than an independent factor; the 2024 ESC guideline therefore recommends the CHA₂DS₂-VA score, which is also reported."},{"q":"Does the score decide anticoagulation?","a":"Guidelines use it as a threshold (generally offered at ≥2 non-sex points, considered at 1), balanced against bleeding risk and patient preference; that decision is clinical."}],"tags":["cha2ds2-vasc","chads-vasc","atrial fibrillation","stroke risk","anticoagulation","cha2ds2-va"],"related":[{"calculator_id":"blood-pressure","reason":"Classify the hypertension criterion."},{"calculator_id":"age","reason":"Compute age from a birth date."}],"links":{"html":"https://tttkmbb.com/medical/cha2ds2-vasc-score","markdown":"https://tttkmbb.com/medical/cha2ds2-vasc-score.md","json":"https://tttkmbb.com/medical/cha2ds2-vasc-score.json","api":"https://tttkmbb.com/api/v1/calculate/cha2ds2-vasc-score","schema":"https://tttkmbb.com/api/v1/calculators/cha2ds2-vasc-score","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-24"},"timestamp":"2026-09-24T01:50:59Z"}