Summary
Rhapsody Envoy Patient History is a read-only backend app for Epic. It helps a provider share the clinical history that a payer needs to confirm medical necessity.
The app reads the chart evidence for one patient and one ordered service. It does not write data to Epic. It does not show a user interface in Epic.
The first use case is ambulatory cardiac monitoring: Holter, extended-wear patch, event monitor and MCOT.
Technical Names in this document
| Term | Meaning |
|---|---|
| Epic | The electronic health record system of the health system |
| FHIR R4 | Fast Healthcare Interoperability Resources, Release 4, the API standard that the app uses |
| Backend Systems app | An Epic app type that connects system to system, with no user sign-in |
| OAuth 2.0 | The authorization standard that the app uses to get an access token |
| JWT | JSON Web Token, a signed token that proves the identity of the app |
| JWK Set URL | A public web address that holds the public keys of the app |
| MCOT | Mobile cardiac outpatient telemetry |
| ICD-10, CPT, LOINC | Code systems for diagnoses, procedures and results |
| PHI | Protected health information |
| BAA | Business associate agreement |
| Rhapsody Envoy | The Rhapsody cloud integration solution that operates the app |
The problem that the app solves
A payer must see evidence before it pays for many services. For cardiac monitoring, this evidence includes symptoms, diagnoses, prior heart tests and current medications.
When the evidence is missing, the payer denies the claim. Staff then search the chart by hand and send records again. This work is slow and it delays payment.
The app collects the evidence automatically when the service is ordered. Staff see gaps in the documentation before the claim goes to the payer.
Who uses the app
| Item | Value |
|---|---|
| Intended purpose | Administrative tasks |
| Intended users | Payers, and the revenue cycle staff who prepare evidence for payers |
| Epic app type | Backend Systems |
| Patient access | None. The app is not patient-facing |
| Clinician workflow | No change. Clinicians use Epic as they do today |
How the app works
The app does a sequence of read operations for each order. Each step below is automatic.
- A clinician orders an ambulatory cardiac monitor in Epic.
- The app receives the order from the monitor service, or from a patient list that the health system controls.
- The app gets an access token from the Epic authorization server of the health system.
- The app finds the patient by medical record number.
- The app reads the order to confirm the service and the date of service.
- The app reads the clinical history for the 6 months before the date of service.
- The app compares the evidence to the criteria of the payer.
- The app shows each gap to the revenue cycle team. The app writes nothing to Epic.
A second read before the claim goes to the payer is the only repeat request.
Data that the app reads
The app reads only the data in this table. All access is Read and Search. The final list of Epic APIs is in the Epic app listing.
| Clinical question | FHIR R4 resource |
|---|---|
| Who is the patient? | Patient |
| Which service was ordered, and when? | ServiceRequest |
| Which diagnoses and symptoms are on file? | Condition (problem list, encounter diagnosis, medical history, health concerns) |
| Which visits occurred in the review period? | Encounter |
| What do the clinical notes say? | DocumentReference and Binary (clinical notes) |
| Which prior heart tests exist (ECG, Holter, echocardiogram)? | DiagnosticReport, Observation |
| Which lab results and vital signs are on file? | Observation (laboratory, vital signs) |
| Which heart medications does the patient take? | MedicationRequest, Medication |
| Which allergies are on file? | AllergyIntolerance |
| Is there a family history of heart disease? | FamilyMemberHistory |
| Which prior procedures and monitors are on file? | Procedure |
| Which care plan applies? | CarePlan |
| Which payer and plan apply? | Coverage |
| Which clinician ordered the service, and what is the specialty? | Practitioner, PractitionerRole |
What the app does not do
- The app does not create, update or delete data in Epic.
- The app does not use Bulk Data export.
- The app does not read data for patients who do not have an order.
- The app does not read a full patient list for the health system.
- The app does not give access to patients or to the public.
- The app does not launch inside the Epic user interface.
Authentication and security
| Control | Value |
|---|---|
| Authorization | OAuth 2.0 client credentials, with a JWT assertion signed with RS384 |
| Public keys | JWK Set URL: https://epic-jwks.sc.rhapsody.health/.well-known/jwks.json |
| Private key | Kept in an encrypted key store. The key never leaves the Rhapsody cloud environment |
| Transport | TLS 1.2 or higher for each request |
| Data at rest | Encrypted |
| Scope | Minimum necessary: one patient for each request, and only the data in the table above |
| Hosting | United States |
| Audit | Each API request is recorded with time, resource and result. PHI is not written to error logs |
| Agreements | A BAA is in place before the app reads PHI |
Patient match
The app finds the patient with the medical record number on the order. If no number is available, the app uses an exact match on name and date of birth.
If the app finds more than one possible patient, it stops. A person then reviews the match. The app never selects a patient by a guess.
Request volume
The app makes approximately 15 to 25 requests for each order. All requests are for one patient. The app does not make scheduled scans of the full database.
Steps for a health system
Before you start, make sure that a BAA is in place with Rhapsody.
- Download the non-production client ID for Rhapsody Envoy Patient History in Epic.
- Enable the APIs in the Epic app listing.
- Confirm that your Epic system can get keys from the JWK Set URL.
- If your firewall blocks the JWK Set URL, upload the public key file that Rhapsody supplies.
- Send these values to Rhapsody: FHIR base URL, token URL, MRN identifier system and Epic version.
- Test the app with one test patient.
- Do steps 1 to 6 again for production.
Support
For questions about this app, send an email to thomas.myers@rhapsody.health.
To learn more about Rhapsody, go to https://rhapsody.health.
Version history
| Version | Date | Change |
|---|---|---|
| 1.0 | October 2026 | First version of this page. The app is in development |