# ATRIA hemorrhage score

ATRIA hemorrhage score

Status: LIVE
Price: $0.005 USDC
`GET /api/calc/atria`
HTML: https://magentlab.com/docs/atria
Markdown: https://magentlab.com/docs/atria.md

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

## What it computes

Compute the Fang 2011 ATRIA hemorrhage score from caller-assigned anemia, severe renal disease, age, prior hemorrhage, and hypertension flags.

## When to use

When an agent needs the published ATRIA AF hemorrhage-risk arithmetic (not HAS-BLED) and must not invent the point total from prose.

## When not to use

- Not a diagnosis. magent does not diagnose hemorrhage or atrial fibrillation.
- Not HAS-BLED. This tool is the Fang 2011 ATRIA hemorrhage score only.
- Not a warfarin order. Not a treatment or anticoagulation recommendation.
- magent does not measure hemoglobin or compute eGFR. Anemia (paper: Hb <13 g/dL men or <12 g/dL women) and severe renal disease (paper: eGFR <30 or dialysis) are caller flags.

## Formula

```
ATRIA = anemia (3) + severe_renal_disease (3) + age_ge_75 (2) + prior_hemorrhage (1) + hypertension (1); max 10; 0-3 low, 4 intermediate, 5-10 high
```

## Citation

[A new risk scheme to predict warfarin-associated hemorrhage: the ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation) Study](https://doi.org/10.1016/j.jacc.2011.03.031)
Fang MC, Go AS, Chang Y, et al.
J Am Coll Cardiol. 2011;58(4):395-401
DOI: [10.1016/j.jacc.2011.03.031](https://doi.org/10.1016/j.jacc.2011.03.031)

## Worked example

### Age 60, all flags false

Given: `age=60, anemia=false, hypertension=false, prior_hemorrhage=false, severe_renal_disease=false`

1. Anemia, severe renal disease, prior hemorrhage, and hypertension false → 0; age 60 is not ≥75 → 0
2. Score = 0 (max 10); risk_band low


### Anemia plus hypertension is intermediate

Given: `age=60, anemia=true, hypertension=true, prior_hemorrhage=false, severe_renal_disease=false`

1. Anemia → 3; hypertension → 1
2. Score = 4 (max 10); risk_band intermediate


## Also searched as

- ATRIA score
- ATRIA bleeding score
- Fang ATRIA hemorrhage
- ATRIA warfarin bleed
- AF ATRIA score
- Anticoagulation and Risk Factors in Atrial Fibrillation

## Parameters

- `anemia` (boolean, required): Anemia as assigned by the caller (paper: hemoglobin <13 g/dL in men or <12 g/dL in women). true or false. Scores 3. magent does not measure hemoglobin.
- `severe_renal_disease` (boolean, required): Severe renal disease as assigned by the caller (paper: eGFR <30 or dialysis). true or false. Scores 3. magent does not compute eGFR.
- `age` (integer, required): Age in years (18-120). ≥75 scores 2 (75 scores; 74 does not).
- `prior_hemorrhage` (boolean, required): Any prior hemorrhage diagnosis as assigned by the caller. true or false. Scores 1.
- `hypertension` (boolean, required): Diagnosed hypertension as assigned by the caller. true or false. Scores 1.

## 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.

Method: `POST /api/calc/atria`
Max items: 25
Price: unit_amount + extra_item_amount * (n - 1) (unit 5000 atomic, extra 2000 atomic)
Status: 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:

```json
{
  "items": [
    {
      "age": "60",
      "anemia": "false",
      "hypertension": "false",
      "prior_hemorrhage": "false",
      "severe_renal_disease": "false"
    },
    {
      "age": "60",
      "anemia": "false",
      "hypertension": "false",
      "prior_hemorrhage": "false",
      "severe_renal_disease": "false"
    }
  ]
}
```

Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/atria

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/atria",
  "items": [
    {
      "components": [
        {
          "factor": "anemia",
          "points": 0,
          "present": false
        },
        {
          "factor": "severe_renal_disease",
          "points": 0,
          "present": false
        },
        {
          "value": 60,
          "factor": "age_ge_75",
          "points": 0,
          "present": false
        },
        {
          "factor": "prior_hemorrhage",
          "points": 0,
          "present": false
        },
        {
          "factor": "hypertension",
          "points": 0,
          "present": false
        }
      ],
      "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": 60,
      "citation": {
        "authors": "Fang MC, Go AS, Chang Y, et al.",
        "doi": "10.1016/j.jacc.2011.03.031",
        "id": "fang-2011",
        "pmid": "21757117",
        "source": "J Am Coll Cardiol. 2011;58(4):395-401",
        "title": "A new risk scheme to predict warfarin-associated hemorrhage: the ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation) Study"
      },
      "formula": "atria",
      "formula_expression": "ATRIA = anemia (3) + severe_renal_disease (3) + age_ge_75 (2) + prior_hemorrhage (1) + hypertension (1); max 10; 0-3 low, 4 intermediate, 5-10 high",
      "max_score": 10,
      "score": 0,
      "risk_band": "low"
    },
    {
      "components": [
        {
          "factor": "anemia",
          "points": 0,
          "present": false
        },
        {
          "factor": "severe_renal_disease",
          "points": 0,
          "present": false
        },
        {
          "value": 60,
          "factor": "age_ge_75",
          "points": 0,
          "present": false
        },
        {
          "factor": "prior_hemorrhage",
          "points": 0,
          "present": false
        },
        {
          "factor": "hypertension",
          "points": 0,
          "present": false
        }
      ],
      "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": 60,
      "citation": {
        "authors": "Fang MC, Go AS, Chang Y, et al.",
        "doi": "10.1016/j.jacc.2011.03.031",
        "id": "fang-2011",
        "pmid": "21757117",
        "source": "J Am Coll Cardiol. 2011;58(4):395-401",
        "title": "A new risk scheme to predict warfarin-associated hemorrhage: the ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation) Study"
      },
      "formula": "atria",
      "formula_expression": "ATRIA = anemia (3) + severe_renal_disease (3) + age_ge_75 (2) + prior_hemorrhage (1) + hypertension (1); max 10; 0-3 low, 4 intermediate, 5-10 high",
      "max_score": 10,
      "score": 0,
      "risk_band": "low"
    }
  ]
}
```

## Response fields

- `formula` (string): atria
- `formula_expression` (string): Exact expression used
- `score` (integer): Total points 0-10
- `max_score` (integer): Always 10
- `risk_band` (string): low when score is 0-3; intermediate when 4; high when 5-10. Not a diagnosis.
- `age_years` (integer): Age used for the ≥75 criterion
- `components` (array): Per-factor points
- `citation` (object): Fang 2011 J Am Coll Cardiol citation
- `disclaimer` (string): Not-a-device notice

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "components": [
    {
      "factor": "anemia",
      "points": 0,
      "present": false
    },
    {
      "factor": "severe_renal_disease",
      "points": 0,
      "present": false
    },
    {
      "value": 60,
      "factor": "age_ge_75",
      "points": 0,
      "present": false
    },
    {
      "factor": "prior_hemorrhage",
      "points": 0,
      "present": false
    },
    {
      "factor": "hypertension",
      "points": 0,
      "present": false
    }
  ],
  "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": 60,
  "citation": {
    "authors": "Fang MC, Go AS, Chang Y, et al.",
    "doi": "10.1016/j.jacc.2011.03.031",
    "id": "fang-2011",
    "pmid": "21757117",
    "source": "J Am Coll Cardiol. 2011;58(4):395-401",
    "title": "A new risk scheme to predict warfarin-associated hemorrhage: the ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation) Study"
  },
  "formula": "atria",
  "formula_expression": "ATRIA = anemia (3) + severe_renal_disease (3) + age_ge_75 (2) + prior_hemorrhage (1) + hypertension (1); max 10; 0-3 low, 4 intermediate, 5-10 high",
  "max_score": 10,
  "score": 0,
  "risk_band": "low"
}
```

## Errors

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

Shared HTTP 402 and 503: https://magentlab.com/docs/payments

## Related tools

- [HAS-BLED](https://magentlab.com/docs/has-bled) — Compute the HAS-BLED bleeding-risk score from discrete clinical flags.
- [ORBIT bleeding score](https://magentlab.com/docs/orbit) — 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.

- GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall).
- HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote.
- Sign accepts[0] (exact, EIP-3009) with validBefore = now + maxTimeoutSeconds (600 seconds), or accepts[1] (batch-settlement deposit/voucher) on product GET. Ping and POST {items} stay exact. Magent retries transient facilitator 429/5xx before answering.
- Retry the same URL with PAYMENT-SIGNATURE (base64 JSON echoing accepted, payload, and extensions when present).
- Success is HTTP 200 JSON plus PAYMENT-RESPONSE. exact settles before the tool. batch-settlement verifies (and deposit-settles) before the tool and commits the charge after HTTP 2xx. HTTP 503: retry the same PAYMENT-SIGNATURE. Mint a new exact nonce only after a new HTTP 402.

- offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront.
- offered `batch-settlement` on eip155:8453: Payment-channel vouchers claimed later in batches. Exact stays accepts[0]. Same-path POST {items} is still exact. extra.assetTransferMethod=eip3009 extra.paymentFlow=authorization.

- not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search.

Same-path POST {items} is still scheme exact: one EIP-3009 authorization for GET unit plus $0.002 per extra item. That is not x402 batch-settlement (payment channels / vouchers).

Shared HTTP 402 and 503 table: https://magentlab.com/docs/payments

Stdio MCP (one process per host): https://magentlab.com/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.
- 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.