# ACEF II cardiac surgery score (Ranucci 2018)

ACEF II

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

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

## What it computes

Compute the Ranucci 2018 ACEF II score from age, left-ventricular ejection fraction, serum creatinine, emergency surgery, and hematocrit.

## When to use

When an agent needs the published Ranucci 2018 ACEF II score for cardiac surgery and must not substitute original ACEF 2009, invent predicted mortality, or issue an operative clearance.

## When not to use

- Not a medical device. Not an operative clearance, cancellation, or monitoring order.
- Ranucci 2018 ACEF II only. This is not original ACEF 2009 (age/EF + 1 if creatinine > 2.0 mg/dL).
- Returns the published ACEF II score only. Does not apply a logistic predicted-mortality equation and does not invent risk bands.
- Creatinine extra 2.0 only when serum creatinine is strictly greater than 2.0 mg/dL; 2.0 scores 0 extra.
- Hematocrit ≥ 36% contributes 0; each percentage point below 36 adds 0.2. magent clamps ejection fraction 10-80, hematocrit 15-60, and age 18-120.
- magent does not examine the patient or assign emergency status from an operative note.

## Formula

```
ACEF II = age/EF + 2.0 (if serum creatinine > 2.0 mg/dL) + 3.0 (if emergency surgery) + 0.2 × (HCT points below 36%)
```

## Citation

[The ACEF II Risk Score for cardiac surgery: updated but still parsimonious](https://doi.org/10.1093/eurheartj/ehx228)
Ranucci M, Pistuddi V, Scolletta S, de Vincentiis C, Menicanti L
Eur Heart J. 2018;39(23):2183-2189
DOI: [10.1093/eurheartj/ehx228](https://doi.org/10.1093/eurheartj/ehx228)

## Worked example

### Age 70, EF 50, creatinine 1.0, elective, HCT 40

Given: `age=70, creatinine_mg_dl=1.0, ejection_fraction_percent=50, emergency_surgery=false, hematocrit_percent=40`

1. age/EF = 70/50 = 1.4
2. creatinine 1.0 is not > 2.0 → 0
3. emergency_surgery false → 0
4. HCT 40 ≥ 36 → anaemia term 0
5. score = 1.4


### Age 70, EF 50, creatinine 2.5, emergency, HCT 30

Given: `age=70, creatinine_mg_dl=2.5, ejection_fraction_percent=50, emergency_surgery=true, hematocrit_percent=30`

1. age/EF = 70/50 = 1.4
2. creatinine 2.5 > 2.0 → +2.0
3. emergency_surgery true → +3.0
4. HCT 30 is 6 points below 36 → 0.2 × 6 = 1.2
5. score = 1.4 + 2.0 + 3.0 + 1.2 = 7.6


## Also searched as

- ACEF II
- ACEF 2
- Ranucci ACEF II
- age creatinine ejection fraction II
- ACEF II risk score
- cardiac surgery ACEF
- ACEF II 2018
- parsimonious cardiac surgery score

## Parameters

- `age` (integer, required): Age in years (18-120). magent clamp; Ranucci 2018 uses age in years.
- `ejection_fraction_percent` (number, required): Left-ventricular ejection fraction in percent (10-80). magent clamp. Denominator of age/EF.
- `creatinine_mg_dl` (number, optional): Serum creatinine in mg/dL (0.1-20). Provide this or creatinine_umol_l, not both. Extra 2.0 only when strictly greater than 2.0 mg/dL (Ranucci 2018).
- `creatinine_umol_l` (number, optional): Serum creatinine in µmol/L (9-1768). Converted as mg/dL = µmol/L / 88.42.
- `emergency_surgery` (boolean, required): true if the operation is emergency cardiac surgery (Ranucci 2018 +3.0). true or false.
- `hematocrit_percent` (number, required): Preoperative hematocrit in percent (15-60). magent clamp. HCT ≥ 36 contributes 0; each percentage point below 36 adds 0.2.

## 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/acef_ii`
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": "70",
      "creatinine_mg_dl": "1.0",
      "ejection_fraction_percent": "50",
      "emergency_surgery": "false",
      "hematocrit_percent": "40"
    },
    {
      "age": "70",
      "creatinine_mg_dl": "1.0",
      "ejection_fraction_percent": "50",
      "emergency_surgery": "false",
      "hematocrit_percent": "40"
    }
  ]
}
```

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

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/acef_ii",
  "items": [
    {
      "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.",
      "citation": {
        "authors": "Ranucci M, Pistuddi V, Scolletta S, de Vincentiis C, Menicanti L",
        "doi": "10.1093/eurheartj/ehx228",
        "id": "ranucci-2018",
        "pmid": "28498904",
        "source": "Eur Heart J. 2018;39(23):2183-2189",
        "title": "The ACEF II Risk Score for cardiac surgery: updated but still parsimonious"
      },
      "formula": "acef_ii",
      "formula_expression": "ACEF II = age/EF + 2.0 (if serum creatinine > 2.0 mg/dL) + 3.0 (if emergency surgery) + 0.2 × (HCT points below 36%)",
      "age_years": 70,
      "score": 1.4,
      "creatinine_mg_dl": 1.0,
      "ejection_fraction_percent": 50.0,
      "emergency_surgery": false,
      "hematocrit_percent": 40.0
    },
    {
      "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.",
      "citation": {
        "authors": "Ranucci M, Pistuddi V, Scolletta S, de Vincentiis C, Menicanti L",
        "doi": "10.1093/eurheartj/ehx228",
        "id": "ranucci-2018",
        "pmid": "28498904",
        "source": "Eur Heart J. 2018;39(23):2183-2189",
        "title": "The ACEF II Risk Score for cardiac surgery: updated but still parsimonious"
      },
      "formula": "acef_ii",
      "formula_expression": "ACEF II = age/EF + 2.0 (if serum creatinine > 2.0 mg/dL) + 3.0 (if emergency surgery) + 0.2 × (HCT points below 36%)",
      "age_years": 70,
      "score": 1.4,
      "creatinine_mg_dl": 1.0,
      "ejection_fraction_percent": 50.0,
      "emergency_surgery": false,
      "hematocrit_percent": 40.0
    }
  ]
}
```

## Response fields

- `formula` (string): acef_ii
- `formula_expression` (string): Exact expression used
- `age_years` (integer): Age used in years
- `ejection_fraction_percent` (number): Left-ventricular ejection fraction used, percent
- `creatinine_mg_dl` (number): Serum creatinine used in mg/dL (after conversion)
- `emergency_surgery` (boolean): true if emergency cardiac surgery
- `hematocrit_percent` (number): Preoperative hematocrit used, percent
- `score` (number): Ranucci 2018 ACEF II score, 4 decimal places. Not a mortality percent.
- `citation` (object): Ranucci 2018 citation
- `disclaimer` (string): Not-a-device notice

## Example JSON

Frozen fixture. Not a live lookup.

```json
{
  "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.",
  "citation": {
    "authors": "Ranucci M, Pistuddi V, Scolletta S, de Vincentiis C, Menicanti L",
    "doi": "10.1093/eurheartj/ehx228",
    "id": "ranucci-2018",
    "pmid": "28498904",
    "source": "Eur Heart J. 2018;39(23):2183-2189",
    "title": "The ACEF II Risk Score for cardiac surgery: updated but still parsimonious"
  },
  "formula": "acef_ii",
  "formula_expression": "ACEF II = age/EF + 2.0 (if serum creatinine > 2.0 mg/dL) + 3.0 (if emergency surgery) + 0.2 × (HCT points below 36%)",
  "age_years": 70,
  "score": 1.4,
  "creatinine_mg_dl": 1.0,
  "ejection_fraction_percent": 50.0,
  "emergency_surgery": false,
  "hematocrit_percent": 40.0
}
```

## Errors

- HTTP 400 `invalid_acef_ii`: ejection_fraction_percent 10-80, creatinine_mg_dl 0.1-20, and hematocrit_percent 15-60 (Ranucci 2018; magent clamps). Returned before settlement; you are not charged.
- HTTP 400 `invalid_age`: age must be an integer from 18 to 120 Returned before settlement; you are not charged.
- HTTP 400 `invalid_creatinine`: creatinine_mg_dl (0.1-20) or creatinine_umol_l (9-1768) is required 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

- [RCRI](https://magentlab.com/docs/rcri) — Sum the six Lee 1999 revised cardiac risk index factors and return class I–IV.

## 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 of accepted and payload). Magent attaches canonical extensions.bazaar on CDP verify/settle; echoing 402 bazaar is optional.
- 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. 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.