# H2FPEF score H2FPEF Status: LIVE Price: $0.005 USDC `GET /api/calc/h2fpef` HTML: https://magentlab.com/docs/h2fpef Markdown: https://magentlab.com/docs/h2fpef.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Sum the Reddy 2018 H2FPEF points score (six components, max 9) and return score and max_score only. ## When to use When an agent has caller-supplied BMI, age, antihypertensive-count flag, AF flag, echo PASP flag, and E/e' flag and needs the published Reddy 2018 points total, not the continuous nomogram, not HFA-PEFF, and not a HFpEF diagnosis or cath decision. ## When not to use - Not a medical device. magent does not diagnose HFpEF and does not examine the patient. - Not a HFpEF diagnosis, treatment order, or cardiac-catheterization substitute. - This is the Reddy 2018 H2FPEF points score only (0-9). It is not the paper's continuous logistic nomogram and not HFA-PEFF. Probability classes (0-1 / 2-5 / 6-9) are not returned. - magent does not read echo. pasp_gt_35 and e_over_e_prime_gt_9 are caller-assigned flags (PASP > 35 mm Hg; E/e' > 9). - magent does not compute BMI from height and weight. BMI 30 and age 60 do not score (strict greater-than). ## Formula ``` H2FPEF = 2*(bmi_kg_m2>30) + antihypertensive_ge_2 + 3*atrial_fibrillation + pasp_gt_35 + (age>60) + e_over_e_prime_gt_9; max 9 (Reddy 2018 points score; not the continuous nomogram, not HFA-PEFF) ``` ## Citation [A Simple, Evidence-Based Approach to Help Guide Diagnosis of Heart Failure With Preserved Ejection Fraction](https://doi.org/10.1161/CIRCULATIONAHA.118.034646) Reddy YNV, Carter RE, Obokata M, Redfield MM, Borlaug BA Circulation. 2018;138(9):861-870 DOI: [10.1161/CIRCULATIONAHA.118.034646](https://doi.org/10.1161/CIRCULATIONAHA.118.034646) ## Worked example ### Age 50, BMI 25, all flags false Given: `age=50, antihypertensive_ge_2=false, atrial_fibrillation=false, bmi_kg_m2=25, e_over_e_prime_gt_9=false, pasp_gt_35=false` 1. BMI 25 is not >30 → 0; antihypertensive_ge_2 false → 0; AF false → 0; PASP flag false → 0; age 50 is not >60 → 0; E/e' flag false → 0 2. Score = 0 (max 9) ### BMI 30.1 only (obesity 2 points) Given: `age=50, antihypertensive_ge_2=false, atrial_fibrillation=false, bmi_kg_m2=30.1, e_over_e_prime_gt_9=false, pasp_gt_35=false` 1. BMI 30.1 > 30 → 2; remaining components 0 2. Score = 2 (max 9) ## Also searched as - H2FPEF - H2FPEF score - Reddy HFpEF score - heart failure with preserved ejection fraction score - HFpEF points score - H2FPEF Reddy 2018 ## Parameters - `age` (integer, required): Age in years (18-120). Reddy 2018 elderly: scores 1 when >60. Age 60 does not score. - `bmi_kg_m2` (number, required): Body-mass index in kg/m^2 (10-80). Reddy 2018 heavy/obesity: scores 2 when >30. BMI 30 does not score. Caller-supplied; magent does not compute BMI from height and weight. - `antihypertensive_ge_2` (boolean, required): Treatment with two or more antihypertensive drugs (Reddy 2018 hypertensive). true or false. Caller-assigned. 1 point if true. - `atrial_fibrillation` (boolean, required): Paroxysmal or persistent atrial fibrillation (Reddy 2018). true or false. Caller-assigned. 3 points if true. - `pasp_gt_35` (boolean, required): Echocardiographic pulmonary artery systolic pressure >35 mm Hg (Reddy 2018 pulmonary hypertension). true or false. Caller-assigned. 1 point if true. magent does not measure PASP. - `e_over_e_prime_gt_9` (boolean, required): E/e' ratio >9 (Reddy 2018 filling pressures). true or false. Caller-assigned. 1 point if true. magent does not measure E/e'. ## 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/h2fpef` 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": "50", "antihypertensive_ge_2": "false", "atrial_fibrillation": "false", "bmi_kg_m2": "25", "e_over_e_prime_gt_9": "false", "pasp_gt_35": "false" }, { "age": "50", "antihypertensive_ge_2": "false", "atrial_fibrillation": "false", "bmi_kg_m2": "25", "e_over_e_prime_gt_9": "false", "pasp_gt_35": "false" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/h2fpef Example 200: ```json { "count": 2, "path": "/api/calc/h2fpef", "items": [ { "components": [ { "value": 25.0, "factor": "obesity", "points": 0, "present": false }, { "factor": "antihypertensive_ge_2", "points": 0, "present": false }, { "factor": "atrial_fibrillation", "points": 0, "present": false }, { "factor": "pasp_gt_35", "points": 0, "present": false }, { "value": 50, "factor": "age_gt_60", "points": 0, "present": false }, { "factor": "e_over_e_prime_gt_9", "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.", "age_years": 50, "citation": { "authors": "Reddy YNV, Carter RE, Obokata M, Redfield MM, Borlaug BA", "doi": "10.1161/CIRCULATIONAHA.118.034646", "id": "reddy-2018", "pmid": "29792299", "source": "Circulation. 2018;138(9):861-870", "title": "A Simple, Evidence-Based Approach to Help Guide Diagnosis of Heart Failure With Preserved Ejection Fraction" }, "formula": "h2fpef", "formula_expression": "H2FPEF = 2*(bmi_kg_m2>30) + antihypertensive_ge_2 + 3*atrial_fibrillation + pasp_gt_35 + (age>60) + e_over_e_prime_gt_9; max 9 (Reddy 2018 points score; not the continuous nomogram, not HFA-PEFF)", "max_score": 9, "score": 0, "bmi_kg_m2": 25.0 }, { "components": [ { "value": 25.0, "factor": "obesity", "points": 0, "present": false }, { "factor": "antihypertensive_ge_2", "points": 0, "present": false }, { "factor": "atrial_fibrillation", "points": 0, "present": false }, { "factor": "pasp_gt_35", "points": 0, "present": false }, { "value": 50, "factor": "age_gt_60", "points": 0, "present": false }, { "factor": "e_over_e_prime_gt_9", "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.", "age_years": 50, "citation": { "authors": "Reddy YNV, Carter RE, Obokata M, Redfield MM, Borlaug BA", "doi": "10.1161/CIRCULATIONAHA.118.034646", "id": "reddy-2018", "pmid": "29792299", "source": "Circulation. 2018;138(9):861-870", "title": "A Simple, Evidence-Based Approach to Help Guide Diagnosis of Heart Failure With Preserved Ejection Fraction" }, "formula": "h2fpef", "formula_expression": "H2FPEF = 2*(bmi_kg_m2>30) + antihypertensive_ge_2 + 3*atrial_fibrillation + pasp_gt_35 + (age>60) + e_over_e_prime_gt_9; max 9 (Reddy 2018 points score; not the continuous nomogram, not HFA-PEFF)", "max_score": 9, "score": 0, "bmi_kg_m2": 25.0 } ] } ``` ## Response fields - `formula` (string): h2fpef - `formula_expression` (string): Exact expression used - `score` (integer): H2FPEF points 0-9 - `max_score` (integer): 9 - `age_years` (integer): Age used for the >60 criterion - `bmi_kg_m2` (number): BMI used for the >30 criterion - `components` (array): Per-factor points - `citation` (object): Reddy et al. Circulation 2018 citation - `disclaimer` (string): Not-a-device notice ## Example JSON Frozen fixture. Not a live lookup. ```json { "components": [ { "value": 25.0, "factor": "obesity", "points": 0, "present": false }, { "factor": "antihypertensive_ge_2", "points": 0, "present": false }, { "factor": "atrial_fibrillation", "points": 0, "present": false }, { "factor": "pasp_gt_35", "points": 0, "present": false }, { "value": 50, "factor": "age_gt_60", "points": 0, "present": false }, { "factor": "e_over_e_prime_gt_9", "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.", "age_years": 50, "citation": { "authors": "Reddy YNV, Carter RE, Obokata M, Redfield MM, Borlaug BA", "doi": "10.1161/CIRCULATIONAHA.118.034646", "id": "reddy-2018", "pmid": "29792299", "source": "Circulation. 2018;138(9):861-870", "title": "A Simple, Evidence-Based Approach to Help Guide Diagnosis of Heart Failure With Preserved Ejection Fraction" }, "formula": "h2fpef", "formula_expression": "H2FPEF = 2*(bmi_kg_m2>30) + antihypertensive_ge_2 + 3*atrial_fibrillation + pasp_gt_35 + (age>60) + e_over_e_prime_gt_9; max 9 (Reddy 2018 points score; not the continuous nomogram, not HFA-PEFF)", "max_score": 9, "score": 0, "bmi_kg_m2": 25.0 } ``` ## Errors - HTTP 400 `invalid_age`: age must be an integer from 18 to 120 Returned before settlement; you are not charged. - HTTP 400 `invalid_bmi_kg_m2`: bmi_kg_m2 must be a number from 10 to 80. 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 - [ADHERE](https://magentlab.com/docs/adhere) — Apply the Fonarow 2005 ADHERE classification and regression tree for in-hospital mortality risk in acutely decompensated heart failure from admission BUN, systolic blood pressure, and serum creatinine. ## 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. - 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.