{
  "resourceType": "StructureDefinition",
  "meta": {
    "lastUpdated": "2017-05-06T14:47:29.107+00:00"
  },
  "extension": [
    {
      "url": "http://hl7.org/fhir/StructureDefinition/structuredefinition-wg",
      "valueCode": "oo"
    }
  ],
  "url": "http://example.org/StructureDefinition/ECGObservation",
  "name": "ECGObservation",
  "status": "draft",
  "date": "2017-05-06T14:02:04.9593346+00:00",
  "description": "StructureDefinition for ECG Observation Resource",
  "fhirVersion": "3.0.0",
  "kind": "resource",
  "abstract": false,
  "type": "Observation",
  "baseDefinition": "http://hl7.org/fhir/StructureDefinition/Observation",
  "derivation": "constraint",
  "differential": {
    "element": [
      {
        "path": "Observation",
        "constraint": [
          {
            "key": "obs-7",
            "severity": "error",
            "human": "Device reference target should have same code as this instance",
            "expression": "true"
          }
        ]
      },
      {
        "path": "Observation.code.coding",
        "max": "1"
      },
      {
        "id": "Observation.code.coding.system",
        "path": "Observation.code.coding.system",
        "fixedUri": "urn:iso:std:iso:11073:10101"
      },
      {
        "id": "Observation.code.coding.code",
        "path": "Observation.code.coding.code",
        "fixedCode": "147842"
      },
      {
        "id": "Observation.code.coding.display",
        "extension": [
          {
            "url": "http://hl7.org/fhir/StructureDefinition/elementdefinition-translatable",
            "valueBoolean": true
          }
        ],
        "path": "Observation.code.coding.display",
        "fixedString": "MDC_ECG_CARD_BEAT_RATE"
      },
      {
        "path": "Observation.valueQuantity",
        "type": [
          {
            "code": "Quantity"
          }
        ]
      },
      {
        "extension": [
          {
            "url": "http://hl7.org/fhir/StructureDefinition/elementdefinition-translatable",
            "valueBoolean": true
          }
        ],
        "path": "Observation.valueQuantity.unit",
        "fixedString": "bpm"
      },
      {
        "path": "Observation.valueQuantity.system",
        "fixedUri": "http://unitsofmeasure.org"
      },
      {
        "path": "Observation.valueQuantity.code",
        "fixedCode": "/min"
      },
      {
        "path": "Observation.device",
        "type": [
          {
            "code": "Reference",
            "targetProfile": "http://example.org/fhir/StructureDefinition/ECGDeviceMetric"
          }
        ]
      }
    ]
  }
}