Blood Pressure Measurement with an absent Diastolic measurement

{
  "resourceType" : "Observation",
  "id" : "blood-pressure-dar",
  "meta" : {
    "profile" : ["http://hl7.org/fhir/StructureDefinition/vitalsigns"]
  },
  "identifier" : [{
    "system" : "urn:ietf:rfc:3986",
    "value" : "urn:uuid:187e0c12-8dd2-67e2-99b2-bf273c878281"
  }],
  "status" : "final",
  "category" : [{
    "coding" : [{
      "system" : "http://terminology.hl7.org/CodeSystem/observation-category",
      "code" : "vital-signs",
      "display" : "Vital Signs"
    }]
  },
  {
    "coding" : [{
      "system" : "http://loinc.org",
      "code" : "85354-9",
      "display" : "Blood pressure panel with all children optional"
    }]
  }],
  "code" : {
    "coding" : [{
      "system" : "http://loinc.org",
      "code" : "85354-9",
      "display" : "Blood pressure panel with all children optional"
    }],
    "text" : "Blood pressure systolic & diastolic"
  },
  "subject" : {
    "reference" : "Patient/example"
  },
  "effectiveDateTime" : "2012-09-17",
  "performer" : [{
    "reference" : "Practitioner/example"
  }],
  "interpretation" : [{
    "coding" : [{
      "system" : "http://terminology.hl7.org/CodeSystem/v3-ObservationInterpretation",
      "code" : "L",
      "display" : "low"
    }],
    "text" : "Below low normal"
  }],
  "bodySite" : {
    "coding" : [{
      "system" : "http://snomed.info/sct",
      "code" : "368209003",
      "display" : "Right arm"
    }]
  },
  "component" : [{
    "extension" : [{
      "url" : "http://hl7.org/fhir/StructureDefinition/observation-componentCategory",
      "valueCodeableConcept" : {
        "coding" : [{
          "system" : "http://loinc.org",
          "code" : "8480-6",
          "display" : "Systolic blood pressure"
        }]
      }
    }],
    "code" : {
      "coding" : [{
        "system" : "http://loinc.org",
        "code" : "8480-6",
        "display" : "Systolic blood pressure"
      },
      {
        "system" : "http://snomed.info/sct",
        "code" : "271649006",
        "display" : "Systolic blood pressure"
      },
      {
        "system" : "http://acme.org/devices/clinical-codes",
        "code" : "bp-s",
        "display" : "Systolic Blood pressure"
      }]
    },
    "valueQuantity" : {
      "value" : 107,
      "unit" : "mmHg",
      "system" : "http://unitsofmeasure.org",
      "code" : "mm[Hg]"
    }
  },
  {
    "extension" : [{
      "url" : "http://hl7.org/fhir/StructureDefinition/observation-componentCategory",
      "valueCodeableConcept" : {
        "coding" : [{
          "system" : "http://loinc.org",
          "code" : "8462-4",
          "display" : "Diastolic blood pressure"
        }]
      }
    }],
    "code" : {
      "coding" : [{
        "system" : "http://loinc.org",
        "code" : "8462-4",
        "display" : "Diastolic blood pressure"
      }]
    },
    "dataAbsentReason" : {
      "coding" : [{
        "system" : "http://terminology.hl7.org/CodeSystem/data-absent-reason",
        "code" : "not-performed",
        "display" : "Not Performed"
      }]
    }
  }]
}