Hemodynamics · LIVE

HCM Risk-SCD

Compute the O'Mahony 2014 HCM Risk-SCD 5-year sudden cardiac death probability from maximal wall thickness, left-atrial diameter, maximal LVOT gradient, family history of SCD, NSVT, unexplained syncope, and age.

LIVE $0.005 USDC GET /api/calc/hcm_risk_scd

Markdown: /docs/hcm-risk-scd.md · Canonical: https://magentlab.com/docs/hcm-risk-scd

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

What it computes

Compute the O'Mahony 2014 HCM Risk-SCD 5-year sudden cardiac death probability from maximal wall thickness, left-atrial diameter, maximal LVOT gradient, family history of SCD, NSVT, unexplained syncope, and age.

When to use

When an agent already has those seven caller-assigned O'Mahony 2014 predictors and needs that paper's 5-year SCD probability and 4%/6% operating-point band. Not an ICD indication or device order.

When not to use

• Not a medical device. Not a diagnosis of hypertrophic cardiomyopathy. Not an ICD indication, implant order, or device-programming recommendation.
• O'Mahony 2014 HCM Risk-SCD only (Eur Heart J 2014; S0 at 5 years = 0.998). magent does not apply later extensions or other society SCD algorithms.
• Caller assigns echo measurements and history flags. magent does not examine the patient, take a family history, interpret Holter monitoring, or read an echocardiogram.
• Age 16-80, maximal wall thickness 10-35 mm, left-atrial diameter 20-70 mm, and maximal LVOT gradient 0-154 mm Hg are the modelled range. Extreme values were underrepresented in the derivation cohort.
• risk_band uses that paper's 4% and 6% 5-year operating points (<4 lower, 4 to <6 intermediate, >=6 higher). It is not an ICD class.

Formula

P_5y = 1 - 0.998^exp(PI); PI = 0.15939858*max_wall_thickness_mm - 0.00294271*max_wall_thickness_mm^2 + 0.0259082*la_diameter_mm + 0.00446131*max_lvot_gradient_mm_hg + 0.4583082*family_history_scd + 0.82639195*nsvt + 0.71650361*unexplained_syncope - 0.01799934*age; flags 1 if true else 0; O'Mahony 2014; risk_band <4 lower, 4 to <6 intermediate, >=6 higher

Citation

Title

A novel clinical risk prediction model for sudden cardiac death in hypertrophic cardiomyopathy (HCM Risk-SCD)

Authors

O'Mahony C, Jichi F, Pavlou M, et al.

Source

Eur Heart J. 2014;35(30):2010-2020

DOI

10.1093/eurheartj/eht439

Worked example

Also searched as

• HCM Risk-SCD
• O'Mahony 2014
• hypertrophic cardiomyopathy SCD
• HCM sudden cardiac death risk
• ESC HCM Risk-SCD
• NSVT HCM SCD
• HCM 5-year SCD probability

Try

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

/api/calc/hcm_risk_scd?age=40&max_wall_thickness_mm=20&la_diameter_mm=40&max_lvot_gradient_mm_hg=20&family_history_scd=false&nsvt=false&unexplained_syncope=false

Full URL: https://api.magentlab.com/api/calc/hcm_risk_scd?age=40&max_wall_thickness_mm=20&la_diameter_mm=40&max_lvot_gradient_mm_hg=20&family_history_scd=false&nsvt=false&unexplained_syncope=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/hcm_risk_scd?age=40&max_wall_thickness_mm=20&la_diameter_mm=40&max_lvot_gradient_mm_hg=20&family_history_scd=false&nsvt=false&unexplained_syncope=false"

Parameters

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/hcm_risk_scd 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": "40",
      "family_history_scd": "false",
      "la_diameter_mm": "40",
      "max_lvot_gradient_mm_hg": "20",
      "max_wall_thickness_mm": "20",
      "nsvt": "false",
      "unexplained_syncope": "false"
    },
    {
      "age": "40",
      "family_history_scd": "false",
      "la_diameter_mm": "40",
      "max_lvot_gradient_mm_hg": "20",
      "max_wall_thickness_mm": "20",
      "nsvt": "false",
      "unexplained_syncope": "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/hcm_risk_scd",
  "items": [
    {
      "age": 40,
      "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": "O'Mahony C, Jichi F, Pavlou M, et al.",
        "doi": "10.1093/eurheartj/eht439",
        "id": "omahony-2014",
        "pmid": "24126876",
        "source": "Eur Heart J. 2014;35(30):2010-2020",
        "title": "A novel clinical risk prediction model for sudden cardiac death in hypertrophic cardiomyopathy (HCM Risk-SCD)"
      },
      "formula": "hcm_risk_scd",
      "formula_expression": "P_5y = 1 - 0.998^exp(PI); PI = 0.15939858*max_wall_thickness_mm - 0.00294271*max_wall_thickness_mm^2 + 0.0259082*la_diameter_mm + 0.00446131*max_lvot_gradient_mm_hg + 0.4583082*family_history_scd + 0.82639195*nsvt + 0.71650361*unexplained_syncope - 0.01799934*age; flags 1 if true else 0; O'Mahony 2014; risk_band <4 lower, 4 to <6 intermediate, >=6 higher",
      "risk_band": "lower",
      "family_history_scd": false,
      "five_year_scd_risk_percent": 2.2,
      "la_diameter_mm": 40.0,
      "max_lvot_gradient_mm_hg": 20.0,
      "max_wall_thickness_mm": 20.0,
      "nsvt": false,
      "prognostic_index": 2.416468,
      "unexplained_syncope": false
    },
    {
      "age": 40,
      "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": "O'Mahony C, Jichi F, Pavlou M, et al.",
        "doi": "10.1093/eurheartj/eht439",
        "id": "omahony-2014",
        "pmid": "24126876",
        "source": "Eur Heart J. 2014;35(30):2010-2020",
        "title": "A novel clinical risk prediction model for sudden cardiac death in hypertrophic cardiomyopathy (HCM Risk-SCD)"
      },
      "formula": "hcm_risk_scd",
      "formula_expression": "P_5y = 1 - 0.998^exp(PI); PI = 0.15939858*max_wall_thickness_mm - 0.00294271*max_wall_thickness_mm^2 + 0.0259082*la_diameter_mm + 0.00446131*max_lvot_gradient_mm_hg + 0.4583082*family_history_scd + 0.82639195*nsvt + 0.71650361*unexplained_syncope - 0.01799934*age; flags 1 if true else 0; O'Mahony 2014; risk_band <4 lower, 4 to <6 intermediate, >=6 higher",
      "risk_band": "lower",
      "family_history_scd": false,
      "five_year_scd_risk_percent": 2.2,
      "la_diameter_mm": 40.0,
      "max_lvot_gradient_mm_hg": 20.0,
      "max_wall_thickness_mm": 20.0,
      "nsvt": false,
      "prognostic_index": 2.416468,
      "unexplained_syncope": false
    }
  ]
}

Response

Example JSON

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

{
  "age": 40,
  "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": "O'Mahony C, Jichi F, Pavlou M, et al.",
    "doi": "10.1093/eurheartj/eht439",
    "id": "omahony-2014",
    "pmid": "24126876",
    "source": "Eur Heart J. 2014;35(30):2010-2020",
    "title": "A novel clinical risk prediction model for sudden cardiac death in hypertrophic cardiomyopathy (HCM Risk-SCD)"
  },
  "formula": "hcm_risk_scd",
  "formula_expression": "P_5y = 1 - 0.998^exp(PI); PI = 0.15939858*max_wall_thickness_mm - 0.00294271*max_wall_thickness_mm^2 + 0.0259082*la_diameter_mm + 0.00446131*max_lvot_gradient_mm_hg + 0.4583082*family_history_scd + 0.82639195*nsvt + 0.71650361*unexplained_syncope - 0.01799934*age; flags 1 if true else 0; O'Mahony 2014; risk_band <4 lower, 4 to <6 intermediate, >=6 higher",
  "risk_band": "lower",
  "family_history_scd": false,
  "five_year_scd_risk_percent": 2.2,
  "la_diameter_mm": 40.0,
  "max_lvot_gradient_mm_hg": 20.0,
  "max_wall_thickness_mm": 20.0,
  "nsvt": false,
  "prognostic_index": 2.416468,
  "unexplained_syncope": false
}

Client errors (HTTP 400)

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

Related tools

• MAGGIC — Sum the Pocock 2013 MAGGIC integer chart from thirteen caller-supplied heart-failure predictors and return the published Table 4 1-year and 3-year death probabilities for scores 0-50.
• SAVE-score — Sum Schmidt 2015 Table 4 SAVE-score cells including the published constant −6 and return class I–V with hospital survival percents.

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.