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Acute Ischemic Stroke — IV Thrombolysis, Endovascular Therapy, and BP Targets

System: Neurology • Reviewed: Sep 1, 2025 • Step 1Step 2Step 3

Synopsis:

For eligible patients within 4.5 hours of onset, offer IV thrombolysis. Evaluate for large-vessel occlusion and consider endovascular thrombectomy within 6 hours, and up to 24 hours based on perfusion imaging selection. Maintain BP control (≤185/110 for lysis; permissive hypertension otherwise) and start secondary prevention.

Key Points

  • Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
  • Set objective targets and reassess frequently.
  • Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.

Algorithm

  1. Rapid stroke recognition; CT to exclude hemorrhage; check glucose.
  2. If within 4.5 h and eligible → IV thrombolysis; manage BP to targets.
  3. Assess for LVO and EVT window (up to 24 h with perfusion selection).
  4. Begin secondary prevention (antiplatelet, statin) and stroke unit care; swallow screen; early rehab.

Clinical Synopsis & Reasoning

For eligible patients within 4.5 hours of onset, offer IV thrombolysis. Evaluate for large-vessel occlusion and consider endovascular thrombectomy within 6 hours, and up to 24 hours based on perfusion imaging selection. Maintain BP control (≤185/110 for lysis; permissive hypertension otherwise) and start secondary prevention.


Treatment Strategy & Disposition

Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.


Epidemiology / Risk Factors

  • Risk varies by comorbidity and precipitants; see citations for condition‑specific data.

Investigations

TestRole / RationaleTypical FindingsNotes
Non-contrast head CT (first)Exclude hemorrhageNo bleedDoor-to-CT within 20 min
CTA head/neck ± CTP/MRILVO identification/selectionTargets for EVTUse perfusion mismatch for extended windows
Glucose, INR/plateletsSafety checksHypoglycemia, coagulopathyDo not delay imaging

High-Risk & Disposition Triggers

TriggerWhy it mattersAction
LVO within EVT windowLarge salvageable penumbraImmediate EVT pathway
BP >185/110 when thrombolysis plannedICH riskRapid BP control to targets
Unknown onset but DWI-FLAIR mismatchPossible thrombolysis candidateAdvanced imaging-based lysis at experienced centers
Anticoagulated patientsBleeding riskReversal/avoid lysis depending on agent/levels
Posterior circulation symptoms with comaHigh mortalityEarly imaging and EVT consideration

Pharmacology

Medication/InterventionMechanismOnsetRole in TherapyLimitations
Alteplase 0.9 mg/kg (max 90 mg) within 4.5 hThrombolyticMinutesImproves outcomes in eligible patientsContraindications apply
Tenecteplase 0.25 mg/kg (max 25 mg) (alternative)ThrombolyticMinutesConsider for LVO prior to EVT (institution dependent)Evolving evidence/guidelines
BP control: Labetalol/Nicardipine/ClevidipineAntihypertensivesMinutesReach ≤185/110 pre-lysis; ≤180/105 post-lysisAvoid hypotension
Aspirin 160–325 mg (if no lysis) or 24 h after lysisAntiplateletHoursSecondary preventionWithhold 24 h post-lysis

Prognosis / Complications

  • Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.

Patient Education / Counseling

  • Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.

References

  1. AHA/ASA Stroke Guidelines (IV thrombolysis/EVT) — Link

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