# Driver 2017 Subtle LAD Occlusion vs Early Repolarization Calculator (4-Variable Formula)

> Driver 2017 Subtle LAD Occlusion vs Early Repolarization Calculator (4-Variable Formula) is a paid API for AI agents from api.magentlab.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Computes the Driver 2017 4-variable formula score to distinguish subtle LAD occlusion from early repolarization (normal-variant STE) in leads V2-V4, flagging likely occlusion when score ≥18.2

## Facts

- Endpoint: GET https://api.magentlab.com/api/calc/subtle_stemi
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/driver-2017-subtle-lad-occlusion-vs-early-repolarization-calculator-4-bc17be72
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_KTSN7KcFgZkSwjW7nif0n

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability driver-2017-subtle-lad-occlusion-vs-early-repolarization-calculator-4-bc17be72
```

Example prompt: Run the Driver 2017 4-variable subtle LAD occlusion formula for me: QTc is 425 ms, QRS amplitude in V2 is 18 mm, R-wave in V4 is 5 mm, and ST elevation at 60ms after J-point in V3 is 2.5 mm — is the score ≥18.2?

## When to prefer this

Use this endpoint when you have explicit numeric ECG measurements (QTc, QRS amplitude in V2, R-wave in V4, STE60 in V3) and need to apply the validated Driver 2017 4-variable formula to distinguish subtle anterior LAD occlusion from benign early repolarization. Prefer this over general ECG interpretation services when the clinical question is specifically this differential, the STE is ≥1 mm in V2-V4, and no obvious occlusion pattern (e.g. tombstoning) is present. Do not use for the 3-variable formula, for obvious STEMIs, or as a substitute for physician ECG reading.

## Known failure modes

- Missing required query parameter (qtc_ms, qrs_v2_mm, r_v4_mm, or ste60_v3_mm) returns a 400-level error
- Out-of-range values (e.g. QTc outside 200-800 ms or STE60 >10 mm) may return a validation error or undefined behavior
- Payment failure (x402) if USDC balance is insufficient or payment header is missing
- Misapplication: formula not valid for patients with obvious occlusion features, LBBB, LVH, or <1 mm STE in V2-V4
- Network timeout on the api.magentlab.com host

## How this service works

Driver 2017 4-variable formula for normal-variant STE in V2-V4 (early repolarization) versus subtle LAD occlusion: formula_value = 0.052*QTc_ms - 0.151*QRS_V2_mm - 0.268*R_V4_mm + 1.062*STE60_V3_mm, 3 decimals. lad_occlusion_suggested is true iff the value is ≥18.2 (derivation highest-accuracy cutpoint). Intended only when ≥1 mm STE in V2-V4 without obvious occlusion features. magent does not read the ECG. Not a STEMI diagnosis, cath-lab order, or 3-variable formula. Not a medical device.

## Output

Returns a numeric formula value rounded to 3 decimal places (computed as 0.052×QTc_ms − 0.151×QRS_V2_mm − 0.268×R_V4_mm + 1.062×STE60_V3_mm), and a boolean flag lad_occlusion_suggested that is true when the value is ≥18.2 (the derivation highest-accuracy cutpoint), and false otherwise. This is a clinical decision-support calculation only — not a diagnosis, STEMI declaration, or cath-lab order.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "queryParams": {
     "type": "object",
     "required": [
      "qtc_ms",
      "qrs_v2_mm",
      "r_v4_mm",
      "ste60_v3_mm"
     ],
     "properties": {
      "qtc_ms": {
       "type": "number",
       "description": "Computerized Bazett QTc in milliseconds (200-800). Driver 2017."
      },
      "r_v4_mm": {
       "type": "number",
       "description": "R-wave amplitude in V4 in millimetres at standard calibration (0.1-50). Driver 2017."
      },
      "qrs_v2_mm": {
       "type": "number",
       "description": "Total QRS amplitude in V2 (R+S) in millimetres at standard calibration (0.1-50). Driver 2017."
      },
      "ste60_v3_mm": {
       "type": "number",
       "description": "ST elevation at 60 ms after the J-point in V3, in millimetres (0-10). Driver 2017."
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/driver-2017-subtle-lad-occlusion-vs-early-repolarization-calculator-4-bc17be72/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.magentlab.com](https://www.zero.xyz/host/api.magentlab.com/llms.txt)