HEARTLAND Protocol FHIR Implementation Guide
0.3.0 -
HEARTLAND Protocol FHIR Implementation Guide
0.3.0 -
HEARTLAND FHIR candidate 0.3.0 — draft, experimental R4 4.0.1 reference. Prepared for technical review; not evidence of clinical validation or vendor interoperability.
| Official URL: https://fhir.heartlandprotocol.org/StructureDefinition/heartland-distance-to-cardiology | Version: 0.3.0 | |||
| Draft as of 2026-09-29 | Computable Name: HeartlandDistanceToCardiology | |||
Driving distance in miles from the patient's residence to the nearest cardiologist. Used by the HEARTLAND risk score: distance >50 miles contributes 1 point. Rural counties without a cardiologist average 87 miles to nearest cardiology care vs 16 miles in counties with one (HEARTLAND Protocol v3.2, Module 2).
Context of Use
This extension may be used on the following element(s)
Patient
Usage info
Usages:
You can also check for usages in the FHIR IG Statistics
Description of Profiles, Differentials, Snapshots, and their representations.
| Name | Flags | Card. | Type | Description & Constraints Filter:   |
|---|---|---|---|---|
  Extension |
0..* | Extension | HEARTLAND Distance to Cardiology | |
  extension |
0..0 | Extension | ||
| url |
1..1 | uri | "https://fhir.heartlandprotocol.org/StructureDefinition/heartland-distance-to-cardiology" | |
  value[x] |
1..1 | Quantity | Value of extension | |
 value |
1..1 | decimal | Numerical value (with implicit precision) | |
| unit |
1..1 | string | Unit representation Required Pattern: mi_us | |
| system |
1..1 | uri | System that defines coded unit form Required Pattern: http://unitsofmeasure.org | |
 code |
1..1 | code | Coded form of the unit Required Pattern: [mi_us] | |
| Documentation for this format | ||||
| Name | Flags | Card. | Type | Description & Constraints Filter: |
|---|---|---|---|---|
 Extension |
0..* | Extension | HEARTLAND Distance to Cardiology | |
 id |
0..1 | string | Unique id for inter-element referencing | |
| extension |
0..0 | Extension Slice: Unordered, Open by value:url | ||
| url |
1..1 | uri | "https://fhir.heartlandprotocol.org/StructureDefinition/heartland-distance-to-cardiology" | |
| value[x] |
1..1 | Quantity | Value of extension | |
| id |
0..1 | string | Unique id for inter-element referencing | |
| extension |
0..* | Extension | Additional content defined by implementations Slice: Unordered, Open by value:url | |
| value |
Σ | 1..1 | decimal | Numerical value (with implicit precision) |
| comparator |
?!Σ | 0..1 | code | < | <= | >= | > - how to understand the value Binding: QuantityComparator (required): How the Quantity should be understood and represented. |
| unit |
Σ | 1..1 | string | Unit representation Required Pattern: mi_us |
| system |
ΣC | 1..1 | uri | System that defines coded unit form Required Pattern: http://unitsofmeasure.org |
| code |
Σ | 1..1 | code | Coded form of the unit Required Pattern: [mi_us] |
| Documentation for this format | ||||
| Path | Status | Usage | ValueSet | Version | Source |
| Extension.value[x].comparator | Base | required | QuantityComparator | 📍4.0.1 | FHIR Std. |
| Id | Grade | Path(s) | Description | Expression |
Summary
Simple Extension with the type Quantity: Driving distance in miles from the patient's residence to the nearest cardiologist. Used by the HEARTLAND risk score: distance >50 miles contributes 1 point. Rural counties without a cardiologist average 87 miles to nearest cardiology care vs 16 miles in counties with one (HEARTLAND Protocol v3.2, Module 2).
Differential ViewDifferential View
| Name | Flags | Card. | Type | Description & Constraints Filter: |
|---|---|---|---|---|
| Extension |
0..* | Extension | HEARTLAND Distance to Cardiology | |
| extension |
0..0 | Extension | ||
| url |
1..1 | uri | "https://fhir.heartlandprotocol.org/StructureDefinition/heartland-distance-to-cardiology" | |
| value[x] |
1..1 | Quantity | Value of extension | |
| value |
1..1 | decimal | Numerical value (with implicit precision) | |
| unit |
1..1 | string | Unit representation Required Pattern: mi_us | |
| system |
1..1 | uri | System that defines coded unit form Required Pattern: http://unitsofmeasure.org | |
| code |
1..1 | code | Coded form of the unit Required Pattern: [mi_us] | |
| Documentation for this format | ||||
Snapshot View
| Name | Flags | Card. | Type | Description & Constraints Filter: |
|---|---|---|---|---|
| Extension |
0..* | Extension | HEARTLAND Distance to Cardiology | |
| id |
0..1 | string | Unique id for inter-element referencing | |
| extension |
0..0 | Extension Slice: Unordered, Open by value:url | ||
| url |
1..1 | uri | "https://fhir.heartlandprotocol.org/StructureDefinition/heartland-distance-to-cardiology" | |
| value[x] |
1..1 | Quantity | Value of extension | |
| id |
0..1 | string | Unique id for inter-element referencing | |
| extension |
0..* | Extension | Additional content defined by implementations Slice: Unordered, Open by value:url | |
| value |
Σ | 1..1 | decimal | Numerical value (with implicit precision) |
| comparator |
?!Σ | 0..1 | code | < | <= | >= | > - how to understand the value Binding: QuantityComparator (required): How the Quantity should be understood and represented. |
| unit |
Σ | 1..1 | string | Unit representation Required Pattern: mi_us |
| system |
ΣC | 1..1 | uri | System that defines coded unit form Required Pattern: http://unitsofmeasure.org |
| code |
Σ | 1..1 | code | Coded form of the unit Required Pattern: [mi_us] |
| Documentation for this format | ||||
| Path | Status | Usage | ValueSet | Version | Source |
| Extension.value[x].comparator | Base | required | QuantityComparator | 📍4.0.1 | FHIR Std. |
| Id | Grade | Path(s) | Description | Expression |
Summary
Simple Extension with the type Quantity: Driving distance in miles from the patient's residence to the nearest cardiologist. Used by the HEARTLAND risk score: distance >50 miles contributes 1 point. Rural counties without a cardiologist average 87 miles to nearest cardiology care vs 16 miles in counties with one (HEARTLAND Protocol v3.2, Module 2).
Other representations of profile: CSV, Excel, Schematron