# Revised cardiac risk index (Lee) RCRI Status: LIVE Price: $0.005 USDC `GET /api/calc/rcri` HTML: https://magentlab.com/docs/rcri Markdown: https://magentlab.com/docs/rcri.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Sum the six Lee 1999 revised cardiac risk index factors and return class I–IV. ## When to use When an agent needs the published RCRI point total and must not invent an operative-clearance decision. ## When not to use - Not an operative clearance, cancellation, or monitoring order. Classes I–IV follow Lee 1999 (0 / 1 / 2 / ≥3 factors). - Does not include age. Does not convert creatinine units; creatinine_gt_2 is the published >2.0 mg/dL cutoff as a flag. ## Formula ``` RCRI = high_risk_surgery + ischemic_heart_disease + congestive_heart_failure + cerebrovascular_disease + insulin_diabetes + creatinine_gt_2; each 1; max 6 ``` ## Citation [Derivation and prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery](https://doi.org/10.1161/01.CIR.100.10.1043) Lee TH, Marcantonio ER, Mangione CM, et al. Circulation. 1999;100(10):1043-1049 DOI: [10.1161/01.CIR.100.10.1043](https://doi.org/10.1161/01.CIR.100.10.1043) ## Worked example ### No factors Given: `cerebrovascular_disease=false, congestive_heart_failure=false, creatinine_gt_2=false, high_risk_surgery=false, insulin_diabetes=false, ischemic_heart_disease=false` 1. score = 0 2. class I ### High-risk surgery, IHD, and CHF Given: `cerebrovascular_disease=false, congestive_heart_failure=true, creatinine_gt_2=false, high_risk_surgery=true, insulin_diabetes=false, ischemic_heart_disease=true` 1. score = 3 2. class IV ## Also searched as - revised cardiac risk index - Lee index - RCRI - preoperative cardiac risk - Goldman revised ## Parameters - `high_risk_surgery` (boolean, required): Intraperitoneal, intrathoracic, or suprainguinal vascular surgery (Lee 1999). true or false. - `ischemic_heart_disease` (boolean, required): History of myocardial infarction, positive exercise test, current chest pain from ischemia, nitrate use, or Q waves (Lee 1999). true or false. - `congestive_heart_failure` (boolean, required): History of heart failure, pulmonary edema, PND, rales, S3, or chest radiograph with vascular redistribution (Lee 1999). true or false. - `cerebrovascular_disease` (boolean, required): History of stroke or TIA (Lee 1999). true or false. - `insulin_diabetes` (boolean, required): Preoperative insulin therapy for diabetes (Lee 1999). true or false. - `creatinine_gt_2` (boolean, required): Preoperative serum creatinine >2.0 mg/dL (Lee 1999). true or false. ## 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/rcri` 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": [ { "cerebrovascular_disease": "false", "congestive_heart_failure": "false", "creatinine_gt_2": "false", "high_risk_surgery": "false", "insulin_diabetes": "false", "ischemic_heart_disease": "false" }, { "cerebrovascular_disease": "false", "congestive_heart_failure": "false", "creatinine_gt_2": "false", "high_risk_surgery": "false", "insulin_diabetes": "false", "ischemic_heart_disease": "false" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/rcri Example 200: ```json { "count": 2, "path": "/api/calc/rcri", "items": [ { "components": [ { "factor": "high_risk_surgery", "points": 0, "present": false }, { "factor": "ischemic_heart_disease", "points": 0, "present": false }, { "factor": "congestive_heart_failure", "points": 0, "present": false }, { "factor": "cerebrovascular_disease", "points": 0, "present": false }, { "factor": "insulin_diabetes", "points": 0, "present": false }, { "factor": "creatinine_gt_2", "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.", "citation": { "authors": "Lee TH, Marcantonio ER, Mangione CM, et al.", "doi": "10.1161/01.CIR.100.10.1043", "id": "lee-1999", "source": "Circulation. 1999;100(10):1043-1049", "title": "Derivation and prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery" }, "formula": "rcri", "formula_expression": "RCRI = high_risk_surgery + ischemic_heart_disease + congestive_heart_failure + cerebrovascular_disease + insulin_diabetes + creatinine_gt_2; each 1; max 6", "max_score": 6, "score": 0, "rcri_class": "I" }, { "components": [ { "factor": "high_risk_surgery", "points": 0, "present": false }, { "factor": "ischemic_heart_disease", "points": 0, "present": false }, { "factor": "congestive_heart_failure", "points": 0, "present": false }, { "factor": "cerebrovascular_disease", "points": 0, "present": false }, { "factor": "insulin_diabetes", "points": 0, "present": false }, { "factor": "creatinine_gt_2", "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.", "citation": { "authors": "Lee TH, Marcantonio ER, Mangione CM, et al.", "doi": "10.1161/01.CIR.100.10.1043", "id": "lee-1999", "source": "Circulation. 1999;100(10):1043-1049", "title": "Derivation and prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery" }, "formula": "rcri", "formula_expression": "RCRI = high_risk_surgery + ischemic_heart_disease + congestive_heart_failure + cerebrovascular_disease + insulin_diabetes + creatinine_gt_2; each 1; max 6", "max_score": 6, "score": 0, "rcri_class": "I" } ] } ``` ## Response fields - `formula` (string): rcri - `formula_expression` (string): Exact expression used - `score` (integer): RCRI points 0-6 - `max_score` (integer): 6 - `rcri_class` (string): Lee 1999 class I (0), II (1), III (2), or IV (≥3). A class, not clearance. - `components` (array): Per-factor points - `citation` (object): Lee et al. Circulation 1999 citation - `disclaimer` (string): Not-a-device notice ## Example JSON Frozen fixture. Not a live lookup. ```json { "components": [ { "factor": "high_risk_surgery", "points": 0, "present": false }, { "factor": "ischemic_heart_disease", "points": 0, "present": false }, { "factor": "congestive_heart_failure", "points": 0, "present": false }, { "factor": "cerebrovascular_disease", "points": 0, "present": false }, { "factor": "insulin_diabetes", "points": 0, "present": false }, { "factor": "creatinine_gt_2", "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.", "citation": { "authors": "Lee TH, Marcantonio ER, Mangione CM, et al.", "doi": "10.1161/01.CIR.100.10.1043", "id": "lee-1999", "source": "Circulation. 1999;100(10):1043-1049", "title": "Derivation and prospective validation of a simple index for prediction of cardiac risk of major noncardiac surgery" }, "formula": "rcri", "formula_expression": "RCRI = high_risk_surgery + ischemic_heart_disease + congestive_heart_failure + cerebrovascular_disease + insulin_diabetes + creatinine_gt_2; each 1; max 6", "max_score": 6, "score": 0, "rcri_class": "I" } ``` ## 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 - [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). - [Glasgow Coma Scale](https://magentlab.com/docs/gcs) — Compute the Glasgow Coma Scale as the sum of caller-assigned eye, verbal, and motor integers. The 1974 or 1976 edition is required. ## 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.