USMLE Prep - Medical Reference Library

Secondary Stroke Prevention — Antiplatelets & Risk Factors

System: Neurology • Reviewed: Aug 31, 2025 • Step 1Step 2Step 3

Synopsis:

Prevent recurrence by tailoring antithrombotic therapy to mechanism and controlling vascular risks; short DAPT for minor stroke/TIA; anticoagulate AF‑related strokes; treat BP and LDL aggressively.

Key Points

  • Stabilize ABCs; begin targeted evaluation without delaying life-saving therapy.
  • Use system-specific risk tools to guide testing and disposition.
  • Order high-yield tests first; escalate imaging when indicated.
  • Start evidence-based initial therapy and reassess frequently.

Algorithm

  1. Primary survey and vitals; IV access and monitors.
  2. Focused history/physical; identify red flags and likely etiologies.
  3. Order system-appropriate labs and imaging (see Investigations).
  4. Initiate guideline-based empiric therapy (see Pharmacology).
  5. Reassess response; arrange consultation and definitive management.

Clinical Synopsis & Reasoning

For Secondary Stroke Prevention Antiplatelets Risk Factors, frame the differential by acuity and pathophysiology, then align diagnostics to the leading hypotheses. Prioritize stabilization while obtaining high‑yield studies such as CT Head (NC) (Hemorrhage exclusion), Glucose (POC) (Exclude hypoglycemia), MRI Brain (selected) (Ischemia/structural). Incorporate bedside imaging and targeted labs to define severity and identify complications; synthesize results with clinical trajectory to refine the working diagnosis and disposition needs.


Treatment Strategy & Disposition

Initiate disease‑directed therapy alongside supportive care, titrating to objective response. Pharmacologic options commonly include Thrombolytic (eligible), Antiepileptics. Use validated frameworks (e.g., Antithrombotic Choices by Mechanism) to guide escalation and site of care. Address precipitating factors, de‑escalate empiric therapies with data, and arrange follow‑up for monitoring and risk‑factor modification; admit patients with instability, high risk of deterioration, or needs for close monitoring.


Epidemiology / Risk Factors

  • Hypertension, AF, atherosclerosis; prior stroke/TIA

Investigations

TestRole / RationaleTypical FindingsNotes
CT Head (NC)Hemorrhage exclusionAcute bloodFirst-line
Glucose (POC)Exclude hypoglycemiaLowTreat promptly
MRI Brain (selected)Ischemia/structuralDiffusion restriction

Antithrombotic Choices by Mechanism

MechanismTherapy
Non‑cardioembolicAspirin or clopidogrel; DAPT short course for minor events
Cardioembolic (AF)DOAC preferred unless contraindicated
Carotid stenosisCEA/CAS in select + antiplatelet
PFO (select <60y)Consider closure after evaluation
Small vessel diseaseSingle antiplatelet + risk factor control

Pharmacology

MedicationMechanismOnsetRole in TherapyLimitations
Packed RBCO₂-carrying capacityHoursSymptomatic anemia per thresholdsTransfusion reactions
PlateletsPrimary hemostasisHoursThrombocytopenia with bleeding/procedureAlloimmunization
Tranexamic acid (selected)AntifibrinolyticMinutesTrauma/postpartum hemorrhage protocolsThrombosis risk

Prognosis / Complications

  • Outcome tied to time-to-reperfusion; aspiration/DVT risks

Patient Education / Counseling

  • Explain red flags and when to seek emergent care.
  • Reinforce medication adherence and follow-up plan.

Prevention Notes

Adherence drives benefit. Use prolonged rhythm monitoring for cryptogenic stroke. Coordinate with sleep medicine for OSA.


References

  1. AHA/ASA Secondary Prevention — Link