Cardiovascular Risk Assessment

Overview

Calculate multiple cardiovascular risk scores from FHIR Patient, Observation, Condition, and MedicationRequest resources. Supports CHA2DS2-VASc (stroke risk in atrial fibrillation), HEART Score (acute chest pain evaluation), Framingham Risk Score (10-year CHD risk), ASCVD Pooled Cohort Equations (10-year ASCVD risk), and HAS-BLED (bleeding risk on anticoagulation). Generate a RiskAssessment FHIR resource with findings and treatment-threshold recommendations.

FHIR Resources Used

Resource	Purpose	Key Fields
Patient	Age, gender, race	birthDate, gender, extension (us-core-race)
Condition	CHF, HTN, DM, stroke, vascular disease, AF	code, clinicalStatus
Observation	BP, cholesterol, HDL, glucose, HbA1c, INR	code, valueQuantity, effectiveDateTime
MedicationRequest	Antiplatelets, anticoagulants, NSAIDs, antihypertensives	medicationCodeableConcept, status
RiskAssessment	Output: risk scores	method, prediction, basis

Instructions

Step 1: Retrieve Patient Demographics

code

Tool: fhir_read
resourceType: "Patient"
id: "[patient-id]"

Extract: age (from birthDate), gender, race (from US Core extension for ASCVD PCE).

Step 2: Retrieve Active Conditions

code

Tool: fhir_search
resourceType: "Condition"
queryParams: "patient=[patient-id]&clinical-status=active"

Identify conditions relevant to scoring. Key SNOMED codes:

•49436004: Atrial fibrillation
•42343007: Congestive heart failure
•38341003: Hypertension
•73211009: Diabetes mellitus
•230690007: Cerebrovascular accident (stroke)
•266257000: Transient ischemic attack (TIA)
•27550009: Vascular disease (peripheral, aortic plaque, prior MI)
•22298006: Myocardial infarction
•400047006: Peripheral vascular disease
•235856003: Hepatic disease
•709044004: Chronic kidney disease
•414545008: Ischemic heart disease

Also search historical conditions for stroke/TIA/MI history:

code

Tool: fhir_search
resourceType: "Condition"
queryParams: "patient=[patient-id]&code=230690007,266257000,22298006"

Step 3: Retrieve Relevant Observations

Blood Pressure:

code

Tool: fhir_search
resourceType: "Observation"
queryParams: "patient=[patient-id]&code=85354-9&_sort=-date&_count=3"

LOINC 85354-9 = Blood pressure panel. Extract systolic (component code 8480-6) and diastolic (8462-4).

Total Cholesterol:

code

Tool: fhir_search
resourceType: "Observation"
queryParams: "patient=[patient-id]&code=2093-3&_sort=-date&_count=1"

LOINC 2093-3 = Total cholesterol.

HDL Cholesterol:

code

Tool: fhir_search
resourceType: "Observation"
queryParams: "patient=[patient-id]&code=2085-9&_sort=-date&_count=1"

LOINC 2085-9 = HDL cholesterol.

LDL Cholesterol:

code

Tool: fhir_search
resourceType: "Observation"
queryParams: "patient=[patient-id]&code=13457-7&_sort=-date&_count=1"

LOINC 13457-7 = LDL cholesterol (calculated).

HbA1c:

code

Tool: fhir_search
resourceType: "Observation"
queryParams: "patient=[patient-id]&code=4548-4&_sort=-date&_count=1"

LOINC 4548-4 = HbA1c.

Troponin (for HEART Score):

code

Tool: fhir_search
resourceType: "Observation"
queryParams: "patient=[patient-id]&code=6598-7,89579-7&_sort=-date&_count=3"

LOINC 6598-7 = Troponin T; 89579-7 = Troponin I high sensitivity.

INR (for HAS-BLED):

code

Tool: fhir_search
resourceType: "Observation"
queryParams: "patient=[patient-id]&code=6301-6&_sort=-date&_count=3"

LOINC 6301-6 = INR.

Creatinine:

code

Tool: fhir_search
resourceType: "Observation"
queryParams: "patient=[patient-id]&code=2160-0&_sort=-date&_count=1"

LOINC 2160-0 = Serum creatinine. For renal function assessment.

Step 4: Retrieve Active Medications

code

Tool: fhir_search
resourceType: "MedicationRequest"
queryParams: "patient=[patient-id]&status=active"

Identify:

•Antihypertensives (for HEART Score, CHA2DS2-VASc HTN criterion)
•Statins (current therapy)
•Anticoagulants: warfarin, apixaban, rivaroxaban, edoxaban, dabigatran
•Antiplatelets: aspirin, clopidogrel, prasugrel, ticagrelor
•NSAIDs (for HAS-BLED)
•Antidepressants/SSRIs (bleeding risk)

Step 5: Determine Which Scores to Calculate

Select based on clinical context:

•Atrial fibrillation present -> CHA2DS2-VASc + HAS-BLED
•Chest pain presentation -> HEART Score
•Primary prevention / statin candidacy -> ASCVD PCE (age 40-79) and/or Framingham
•If unclear, calculate all applicable scores

Refer to references/cv-scoring-systems.md for complete scoring criteria.

Step 6: Calculate Scores and Generate Recommendations

Apply scoring criteria from reference tables. Map scores to treatment thresholds per references/acc-aha-guidelines.md.

Step 7: Create RiskAssessment Resource

code

Tool: fhir_create
resourceType: "RiskAssessment"
resource: {
  "resourceType": "RiskAssessment",
  "status": "final",
  "subject": {"reference": "Patient/[patient-id]"},
  "occurrenceDateTime": "[current-datetime]",
  "method": {
    "coding": [{"system": "http://snomed.info/sct", "code": "225338004", "display": "Risk assessment"}]
  },
  "prediction": [
    {
      "outcome": {"text": "[Score name]: [value] - [risk level]"},
      "probabilityDecimal": [probability if applicable],
      "qualitativeRisk": {"coding": [{"system": "http://terminology.hl7.org/CodeSystem/risk-probability", "code": "[low|moderate|high]"}]}
    }
  ],
  "basis": [
    {"reference": "Condition/[relevant-condition-id]"},
    {"reference": "Observation/[relevant-observation-id]"}
  ],
  "note": [{"text": "[Treatment recommendations based on risk level]"}]
}

Step 8: Format Output

code

CARDIOVASCULAR RISK ASSESSMENT
===============================
Patient: [name] | Age: [age] | Sex: [sex]
Assessment Date: [datetime]

SCORES
------
[Score Name]: [value] - [risk level]
  Components: [list scored items]
  Recommendation: [guideline-based recommendation]

[Repeat for each calculated score]

CURRENT THERAPY
---------------
Anticoagulation: [current or none]
Antiplatelets: [current or none]
Statin: [current or none]
Antihypertensives: [current or none]

RECOMMENDATIONS
---------------
[Prioritized list of guideline-based recommendations]

Examples

Example 1: AFib Patient -- Stroke and Bleeding Risk

User says: "What's the stroke risk for patient 54321? She has AFib."

Actions:

•fhir_read Patient/54321 -- 74F
•fhir_search Condition active -- AF, HTN, DM, prior TIA
•fhir_search Observation BP -- 142/88
•fhir_search Observation INR -- 2.8 (on warfarin)
•fhir_search MedicationRequest active -- warfarin, metformin, lisinopril
•Calculate: CHA2DS2-VASc = 6 (age 74 = 2, female = 1, HTN = 1, DM = 1, TIA = 2, minus 1 for overlap... recalculate: age 65-74 = 1, female = 1, HTN = 1, DM = 1, stroke/TIA = 2 = total 6)
•Calculate: HAS-BLED = 2 (HTN = 1, age >65 = 1)
•fhir_create RiskAssessment

Result:

code

CARDIOVASCULAR RISK ASSESSMENT
===============================
Patient: Eleanor Voss | Age: 74 | Sex: Female

SCORES
------
CHA2DS2-VASc: 6/9 - HIGH RISK
  CHF: 0, HTN: 1, Age 65-74: 1, DM: 1, Stroke/TIA: 2, Vascular: 0, Sex (female): 1
  Annual stroke risk: ~9.8%
  Recommendation: Oral anticoagulation strongly indicated

HAS-BLED: 2/9 - MODERATE BLEEDING RISK
  HTN (uncontrolled): 1, Renal/Liver: 0, Stroke: 0, Bleeding hx: 0,
  Labile INR: 0, Age >65: 1, Drugs/Alcohol: 0
  Recommendation: Anticoagulation benefits outweigh bleeding risk. Monitor INR closely.

CURRENT THERAPY
---------------
Anticoagulation: Warfarin (active)
Statin: None

RECOMMENDATIONS
---------------
1. Continue anticoagulation -- CHA2DS2-VASc 6 strongly supports OAC
2. Consider DOAC switch (apixaban/rivaroxaban) -- lower intracranial hemorrhage risk vs warfarin
3. Optimize BP control -- SBP 142 exceeds target
4. Evaluate statin candidacy -- age 74 with DM and HTN

Example 2: Chest Pain Evaluation with HEART Score

User says: "Calculate HEART score for patient 99887, presenting with chest pain"

Actions:

•fhir_read Patient/99887 -- 58M
•fhir_search Condition active -- HTN, hyperlipidemia, prior PCI (2019)
•fhir_search Observation troponin -- high-sensitivity troponin I: 45 ng/L (upper limit 26)
•fhir_search Observation ECG interpretation -- no specific ST changes
•Calculate: HEART = 7 (History moderately suspicious = 1, ECG non-diagnostic = 1, Age 55-64 = 1, Risk factors >=3 = 2, Troponin 1-3x ULN = 1... recalculate with prior PCI as significant risk = 2)

Result:

code

HEART Score: 7/10 - HIGH RISK
  History: 1 (moderately suspicious)
  ECG: 1 (non-specific repolarization disturbance)
  Age: 1 (45-64)
  Risk factors: 2 (HTN, hyperlipidemia, prior PCI)
  Troponin: 2 (>3x normal limit -- rechecked: 45/26 = 1.7x = 1 point)
  Corrected total: 6/10 - HIGH RISK

Recommendation: HEART >= 7: admit, cardiology consult, early invasive strategy.
HEART 4-6: observation unit, serial troponins, stress testing or CCTA.
This patient at 6: admit for observation, serial troponins q3h, consider non-invasive testing.

Troubleshooting

Cholesterol Values Not Found for ASCVD Calculation

•Check alternate LOINC codes: 2093-3 (cholesterol, total), 48620-9 (cholesterol total, calculated). For HDL: 2085-9 or 14646-4 (HDL direct). Expand search window with &date=ge[date-1-year] to find most recent lipid panel.
•If no lipid values exist, ASCVD PCE cannot be calculated. Recommend ordering fasting lipid panel.

Race Data Not Available for ASCVD PCE

•ASCVD PCE uses race-specific coefficients (White, African American). Check US Core race extension on Patient resource. If race is not documented or is other than White/African American, use White coefficients and note the limitation. The equations have not been validated in other racial/ethnic groups.

Multiple Conditions Match Same Criterion

•For CHA2DS2-VASc, each criterion scores once regardless of how many matching conditions exist. Prior stroke + prior TIA = still 2 points (single stroke/TIA category), not 4 points. Deduplicate condition matches per scoring criterion.

Related Skills

•clinical-summary-generator -- for full patient context before risk assessment
•medication-reconciliation -- to verify current anticoagulant/statin therapy
•drug-interaction-checker -- when recommending new anticoagulant or statin therapy