# Modified Sgarbossa criteria

Modified Sgarbossa

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

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

## What it computes

Apply the Smith 2012 unweighted modified Sgarbossa rule from three caller-assigned ECG flags and return whether any criterion is met.

## When to use

When an agent already has the three Smith 2012 modified Sgarbossa flags for a tracing with left bundle-branch block and needs whether the unweighted any-of rule is positive. magent does not measure the ECG. Use the original Sgarbossa 1996 5/3/2 points score when that published weighting is required.

## When not to use

- Not a medical device.
- Not a diagnosis of myocardial infarction, STEMI equivalent, or reperfusion decision.
- magent does not measure the ECG. Each flag is caller-assigned.
- This is Smith 2012 unweighted modified Sgarbossa (any of three flags). Not the original Sgarbossa 1996 5/3/2 points score.
- Not a 5 mm discordant ST-elevation rule. The third flag is excessive discordant STE with ST/S ratio ≤ −0.25 as assigned by the caller.

## Formula

```
modified_sgarbossa iff concordant_st_elevation_1mm or concordant_st_depression_v1_v3 or excessive_discordant_ste_st_s_ge_0_25 (Smith 2012 unweighted modified Sgarbossa; not Sgarbossa 1996 5/3/2 points; not a 5 mm discordant rule)
```

## Citation

[Diagnosis of ST-elevation myocardial infarction in the presence of left bundle branch block with the ST-elevation to S-wave ratio in a modified Sgarbossa rule](https://doi.org/10.1016/j.annemergmed.2012.07.119)
Smith SW, Dodd KW, Henry TD, Dvorak DM, Pearce LA
Ann Emerg Med. 2012;60(6):766-776
DOI: [10.1016/j.annemergmed.2012.07.119](https://doi.org/10.1016/j.annemergmed.2012.07.119)

## Worked example

### All three flags false (modified Sgarbossa negative)

Given: `concordant_st_depression_v1_v3=false, concordant_st_elevation_1mm=false, excessive_discordant_ste_st_s_ge_0_25=false`

1. concordant_st_elevation_1mm false
2. concordant_st_depression_v1_v3 false
3. excessive_discordant_ste_st_s_ge_0_25 false
4. modified_sgarbossa_any is false; modified_sgarbossa is false


### Concordant ST elevation ≥1 mm only (modified Sgarbossa positive)

Given: `concordant_st_depression_v1_v3=false, concordant_st_elevation_1mm=true, excessive_discordant_ste_st_s_ge_0_25=false`

1. concordant_st_elevation_1mm true meets the first Smith 2012 criterion
2. The other two flags are false
3. modified_sgarbossa_any is true; modified_sgarbossa is true


## Also searched as

- Smith modified Sgarbossa
- modified Sgarbossa criteria
- Smith 2012 ST/S ratio
- excessive discordant ST elevation
- concordant ST elevation LBBB
- unweighted modified Sgarbossa
- STEMI equivalent LBBB
- Sgarbossa ST/S 0.25

## Parameters

- `concordant_st_elevation_1mm` (boolean, required): Concordant ST elevation ≥1 mm in a lead with a positive QRS as assigned by the caller (Smith 2012). true or false. magent does not measure the ECG.
- `concordant_st_depression_v1_v3` (boolean, required): Concordant ST depression ≥1 mm in V1, V2, or V3 as assigned by the caller (Smith 2012). true or false. magent does not measure the ECG.
- `excessive_discordant_ste_st_s_ge_0_25` (boolean, required): ≥1 mm discordant ST elevation with ST/S ratio ≤ −0.25 (STE ≥25% of the preceding S-wave depth) as assigned by the caller (Smith 2012). true or false. magent does not measure the ECG. Not the original Sgarbossa 1996 5 mm discordant rule.

## 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/modified_sgarbossa`
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": [
    {
      "concordant_st_depression_v1_v3": "false",
      "concordant_st_elevation_1mm": "false",
      "excessive_discordant_ste_st_s_ge_0_25": "false"
    },
    {
      "concordant_st_depression_v1_v3": "false",
      "concordant_st_elevation_1mm": "false",
      "excessive_discordant_ste_st_s_ge_0_25": "false"
    }
  ]
}
```

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

Example 200:

```json
{
  "count": 2,
  "path": "/api/calc/modified_sgarbossa",
  "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": "Smith SW, Dodd KW, Henry TD, Dvorak DM, Pearce LA",
        "doi": "10.1016/j.annemergmed.2012.07.119",
        "id": "smith-2012",
        "pmid": "22939607",
        "source": "Ann Emerg Med. 2012;60(6):766-776",
        "title": "Diagnosis of ST-elevation myocardial infarction in the presence of left bundle branch block with the ST-elevation to S-wave ratio in a modified Sgarbossa rule"
      },
      "formula": "modified_sgarbossa",
      "formula_expression": "modified_sgarbossa iff concordant_st_elevation_1mm or concordant_st_depression_v1_v3 or excessive_discordant_ste_st_s_ge_0_25 (Smith 2012 unweighted modified Sgarbossa; not Sgarbossa 1996 5/3/2 points; not a 5 mm discordant rule)",
      "criteria": [
        {
          "factor": "concordant_st_elevation_1mm",
          "met": false
        },
        {
          "factor": "concordant_st_depression_v1_v3",
          "met": false
        },
        {
          "factor": "excessive_discordant_ste_st_s_ge_0_25",
          "met": false
        },
        {
          "factor": "modified_sgarbossa_any",
          "met": false
        }
      ],
      "modified_sgarbossa": 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.",
      "citation": {
        "authors": "Smith SW, Dodd KW, Henry TD, Dvorak DM, Pearce LA",
        "doi": "10.1016/j.annemergmed.2012.07.119",
        "id": "smith-2012",
        "pmid": "22939607",
        "source": "Ann Emerg Med. 2012;60(6):766-776",
        "title": "Diagnosis of ST-elevation myocardial infarction in the presence of left bundle branch block with the ST-elevation to S-wave ratio in a modified Sgarbossa rule"
      },
      "formula": "modified_sgarbossa",
      "formula_expression": "modified_sgarbossa iff concordant_st_elevation_1mm or concordant_st_depression_v1_v3 or excessive_discordant_ste_st_s_ge_0_25 (Smith 2012 unweighted modified Sgarbossa; not Sgarbossa 1996 5/3/2 points; not a 5 mm discordant rule)",
      "criteria": [
        {
          "factor": "concordant_st_elevation_1mm",
          "met": false
        },
        {
          "factor": "concordant_st_depression_v1_v3",
          "met": false
        },
        {
          "factor": "excessive_discordant_ste_st_s_ge_0_25",
          "met": false
        },
        {
          "factor": "modified_sgarbossa_any",
          "met": false
        }
      ],
      "modified_sgarbossa": false
    }
  ]
}
```

## Response fields

- `formula` (string): modified_sgarbossa
- `formula_expression` (string): Smith 2012 unweighted modified Sgarbossa: positive if any of the three caller-assigned flags
- `modified_sgarbossa` (boolean): true iff any of concordant_st_elevation_1mm, concordant_st_depression_v1_v3, or excessive_discordant_ste_st_s_ge_0_25 is true. Not a diagnosis. Not a weighted score.
- `criteria` (array): Per-flag rows plus modified_sgarbossa_any (met iff any of the three flags is true)
- `citation` (object): Smith 2012 Annals of Emergency Medicine 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": "Smith SW, Dodd KW, Henry TD, Dvorak DM, Pearce LA",
    "doi": "10.1016/j.annemergmed.2012.07.119",
    "id": "smith-2012",
    "pmid": "22939607",
    "source": "Ann Emerg Med. 2012;60(6):766-776",
    "title": "Diagnosis of ST-elevation myocardial infarction in the presence of left bundle branch block with the ST-elevation to S-wave ratio in a modified Sgarbossa rule"
  },
  "formula": "modified_sgarbossa",
  "formula_expression": "modified_sgarbossa iff concordant_st_elevation_1mm or concordant_st_depression_v1_v3 or excessive_discordant_ste_st_s_ge_0_25 (Smith 2012 unweighted modified Sgarbossa; not Sgarbossa 1996 5/3/2 points; not a 5 mm discordant rule)",
  "criteria": [
    {
      "factor": "concordant_st_elevation_1mm",
      "met": false
    },
    {
      "factor": "concordant_st_depression_v1_v3",
      "met": false
    },
    {
      "factor": "excessive_discordant_ste_st_s_ge_0_25",
      "met": false
    },
    {
      "factor": "modified_sgarbossa_any",
      "met": false
    }
  ],
  "modified_sgarbossa": false
}
```

## Errors

- 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

- [Sgarbossa](https://magentlab.com/docs/sgarbossa) — Sum the three Sgarbossa 1996 GUSTO-1 ECG criteria in left bundle-branch block and return whether the total is ≥3.
- [HEART score](https://magentlab.com/docs/heart) — Compute the HEART score as age points plus caller-assigned history, ECG, risk factors, and troponin (each 0-2).
- [HEART Pathway](https://magentlab.com/docs/heart-pathway) — Apply the Mahler 2015 HEART Pathway and return whether a caller-assigned HEART score plus 0-hour and 3-hour troponin flags meet the published early-discharge rule.

## 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.