Atrial fibrillation · LIVE

CHA2DS2-VA calculator

CHA2DS2-VA

Compute the ESC 2024 CHA2DS2-VA stroke-risk score from age and discrete clinical flags, without a sex category.

LIVE $0.005 USDC GET /api/calc/cha2ds2_va

Markdown: /docs/cha2ds2-va.md · Canonical: https://magentlab.com/docs/cha2ds2-va

Not a medical device. Not a diagnosis, dose, or listing recommendation.

What it computes

Compute the ESC 2024 CHA2DS2-VA stroke-risk score from age and discrete clinical flags, without a sex category.

When to use

When an agent needs the 2024 ESC CHA2DS2-VA total (VASc without sex) and must not invent points from a chart narrative.

When not to use

Not a medical device and not an anticoagulation order or treatment recommendation.
Not CHA2DS2-VASc. This tool drops the sex category (max 8, not 9) per ESC 2024.
Flags are caller-supplied booleans. magent does not infer CHF, stroke, or vascular disease from text.
Does not report annual stroke percentages. OAC none / consider / recommended follows ESC 2024 score bands only.

Formula

CHA2DS2-VA = CHF 1 + HTN 1 + Age≥75 2 (or 65-74 1) + diabetes 1 + stroke/TIA 2 + vascular 1; no sex; max 8; OAC none (0) consider (1) recommended (≥2) (ESC 2024)

Citation

Title: 2024 ESC Guidelines for the management of atrial fibrillation developed in collaboration with the European Association for Cardio-Thoracic Surgery (EACTS)
Authors: Van Gelder IC, Rienstra M, Bunting KV, et al.
Source: Eur Heart J. 2024;45(36):3314-3414
DOI: 10.1093/eurheartj/ehae176

Worked example

Age 78, all flags false

Given: age=78chf=falsediabetes=falsehypertension=falsestroke_tia=falsevascular_disease=false

Age ≥75 → 2; CHF, hypertension, diabetes, stroke/TIA, and vascular disease false → 0
Score = 2 (max 8); OAC recommended

Also searched as

CHA2DS2-VA
CHA2DS2VA
ESC 2024 AF score
CHA2DS2-VA without sex
Van Gelder AF score
AF stroke score VA

Try

Opens the live endpoint. Unpaid browser requests show the paywall; agents should send Accept: application/json.

/api/calc/cha2ds2_va?age=78&chf=false&hypertension=false&diabetes=false&stroke_tia=false&vascular_disease=false

Full URL: https://api.magentlab.com/api/calc/cha2ds2_va?age=78&chf=false&hypertension=false&diabetes=false&stroke_tia=false&vascular_disease=false

Call

Expect HTTP 402 until you retry with PAYMENT-SIGNATURE. Incomplete query params return HTTP 400 before any quote or charge.

curl -i -H "Accept: application/json" "https://api.magentlab.com/api/calc/cha2ds2_va?age=78&chf=false&hypertension=false&diabetes=false&stroke_tia=false&vascular_disease=false"

Parameters

Name	Type	Required	Description
`age`	integer	required	Age in years (18-120). ≥75 scores 2; 65-74 scores 1.
`chf`	boolean	required	Congestive heart failure or LV dysfunction. true or false.
`hypertension`	boolean	required	Hypertension history. true or false.
`diabetes`	boolean	required	Diabetes mellitus. true or false.
`stroke_tia`	boolean	required	Prior stroke, TIA, or arterial thromboembolism. true or false (2 points).
`vascular_disease`	boolean	required	Prior MI, peripheral artery disease, or aortic plaque. true or false.

Bulk (POST)

POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement.

POST /api/calc/cha2ds2_va Max 25 unit_amount + extra_item_amount * (n - 1) extra $0.002 PREVIEW

1 to 25 items. Each item uses the same keys as the GET query parameters.
POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows.
The first invalid item fails the whole request (index in the 400 JSON). You are not charged.
HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row.
Catalog misses (empty matches, found=false) stay paid 200s inside that slot.
x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items.

Example request (fixture)

{
  "items": [
    {
      "age": "78",
      "chf": "false",
      "diabetes": "false",
      "hypertension": "false",
      "stroke_tia": "false",
      "vascular_disease": "false"
    },
    {
      "age": "78",
      "chf": "false",
      "diabetes": "false",
      "hypertension": "false",
      "stroke_tia": "false",
      "vascular_disease": "false"
    }
  ]
}

Open bulk paywall →

Opens a two-item fixture on the API host. Unpaid browsers get the same MetaMask paywall as GET; Pay retries POST with those items.

Example 200 (fixture)

{
  "count": 2,
  "path": "/api/calc/cha2ds2_va",
  "items": [
    {
      "components": [
        {
          "factor": "congestive_heart_failure",
          "points": 0,
          "present": false
        },
        {
          "factor": "hypertension",
          "points": 0,
          "present": false
        },
        {
          "value": 78,
          "factor": "age",
          "points": 2,
          "present": true
        },
        {
          "factor": "diabetes",
          "points": 0,
          "present": false
        },
        {
          "factor": "stroke_tia_thromboembolism",
          "points": 0,
          "present": false
        },
        {
          "factor": "vascular_disease",
          "points": 0,
          "present": false
        }
      ],
      "category": "recommended",
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "age_years": 78,
      "citation": {
        "authors": "Van Gelder IC, Rienstra M, Bunting KV, et al.",
        "doi": "10.1093/eurheartj/ehae176",
        "id": "van-gelder-2024",
        "pmid": "39210723",
        "source": "Eur Heart J. 2024;45(36):3314-3414",
        "title": "2024 ESC Guidelines for the management of atrial fibrillation developed in collaboration with the European Association for Cardio-Thoracic Surgery (EACTS)"
      },
      "formula": "cha2ds2_va",
      "formula_expression": "CHA2DS2-VA = CHF 1 + HTN 1 + Age≥75 2 (or 65-74 1) + diabetes 1 + stroke/TIA 2 + vascular 1; no sex; max 8; OAC none (0) consider (1) recommended (≥2) (ESC 2024)",
      "max_score": 8,
      "score": 2,
      "oac": "recommended"
    },
    {
      "components": [
        {
          "factor": "congestive_heart_failure",
          "points": 0,
          "present": false
        },
        {
          "factor": "hypertension",
          "points": 0,
          "present": false
        },
        {
          "value": 78,
          "factor": "age",
          "points": 2,
          "present": true
        },
        {
          "factor": "diabetes",
          "points": 0,
          "present": false
        },
        {
          "factor": "stroke_tia_thromboembolism",
          "points": 0,
          "present": false
        },
        {
          "factor": "vascular_disease",
          "points": 0,
          "present": false
        }
      ],
      "category": "recommended",
      "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
      "age_years": 78,
      "citation": {
        "authors": "Van Gelder IC, Rienstra M, Bunting KV, et al.",
        "doi": "10.1093/eurheartj/ehae176",
        "id": "van-gelder-2024",
        "pmid": "39210723",
        "source": "Eur Heart J. 2024;45(36):3314-3414",
        "title": "2024 ESC Guidelines for the management of atrial fibrillation developed in collaboration with the European Association for Cardio-Thoracic Surgery (EACTS)"
      },
      "formula": "cha2ds2_va",
      "formula_expression": "CHA2DS2-VA = CHF 1 + HTN 1 + Age≥75 2 (or 65-74 1) + diabetes 1 + stroke/TIA 2 + vascular 1; no sex; max 8; OAC none (0) consider (1) recommended (≥2) (ESC 2024)",
      "max_score": 8,
      "score": 2,
      "oac": "recommended"
    }
  ]
}

Response

Field	Type	Description
`formula`	string	cha2ds2_va
`formula_expression`	string	Exact expression used
`score`	integer	Total points 0-8
`max_score`	integer	Always 8
`oac`	string	ESC 2024 oral-anticoagulation band: none (score 0), consider (score 1), or recommended (score ≥2). Not an order.
`category`	string	Same ESC 2024 band as oac: none, consider, or recommended. Not an order.
`age_years`	integer	Age used for A2/A scoring
`components`	array	Per-factor points
`citation`	object	ESC 2024 Eur Heart J citation
`disclaimer`	string	Not-a-device notice

Example JSON

Machine form of the same example. Frozen fixture. Not a live lookup.

{
  "components": [
    {
      "factor": "congestive_heart_failure",
      "points": 0,
      "present": false
    },
    {
      "factor": "hypertension",
      "points": 0,
      "present": false
    },
    {
      "value": 78,
      "factor": "age",
      "points": 2,
      "present": true
    },
    {
      "factor": "diabetes",
      "points": 0,
      "present": false
    },
    {
      "factor": "stroke_tia_thromboembolism",
      "points": 0,
      "present": false
    },
    {
      "factor": "vascular_disease",
      "points": 0,
      "present": false
    }
  ],
  "category": "recommended",
  "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.",
  "age_years": 78,
  "citation": {
    "authors": "Van Gelder IC, Rienstra M, Bunting KV, et al.",
    "doi": "10.1093/eurheartj/ehae176",
    "id": "van-gelder-2024",
    "pmid": "39210723",
    "source": "Eur Heart J. 2024;45(36):3314-3414",
    "title": "2024 ESC Guidelines for the management of atrial fibrillation developed in collaboration with the European Association for Cardio-Thoracic Surgery (EACTS)"
  },
  "formula": "cha2ds2_va",
  "formula_expression": "CHA2DS2-VA = CHF 1 + HTN 1 + Age≥75 2 (or 65-74 1) + diabetes 1 + stroke/TIA 2 + vascular 1; no sex; max 8; OAC none (0) consider (1) recommended (≥2) (ESC 2024)",
  "max_score": 8,
  "score": 2,
  "oac": "recommended"
}

Client errors (HTTP 400)

Invalid params return 400 without charge. Shared HTTP 402 and 503 meanings: Payments.

HTTP	Code	When
400	`invalid_age`	age must be an integer from 18 to 120 Returned before settlement; you are not charged.
400	`invalid_flag`	boolean clinical flags must be true or false Returned before settlement; you are not charged.
400	`invalid_items`	POST body must be a JSON object with only an items array Returned before settlement; you are not charged.
400	`invalid_item_count`	items must be an array of 1 to 25 objects Returned before settlement; you are not charged.
400	`invalid_item`	each items entry must be a JSON object Returned before settlement; you are not charged.

Related tools

CHA2DS2-VASc — Compute the CHA2DS2-VASc stroke-risk score from discrete clinical flags.
CHADS2 — Compute the CHADS2 stroke-risk score from discrete clinical flags.
HAS-BLED — Compute the HAS-BLED bleeding-risk score from discrete clinical flags.
ORBIT bleeding score — Compute the O'Brien 2015 ORBIT bleeding score from age and caller-assigned anemia, bleeding history, insufficient kidney, and antiplatelet flags.

Payment

Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s. Unpaid valid requests return HTTP 402 with a base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote: retry the same PAYMENT-SIGNATURE. Full handshake and shared payment errors: Payments. Stdio MCP: /docs/mcp.

Guarantees

HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON.
exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE.
HTTP 402 is unpaid only. Do not sign a second authorization because of a 503.
Execution is timeout-bounded and concurrency-capped.
Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.