Lacunar Infarct - Emergency Management

Background and Pathophysiology

• Lipohyalinosis and fibrinoid angiopathy - driven by chronic hypertension
• Microatheroma at the ostium of penetrating arteries (most common cause of lacunes >50 µm)
• Less often: cardiac or artery-to-artery embolism

Step 1 - Immediate Assessment (0-15 min)

Step 2 - Emergent Neuroimaging

• Non-contrast CT head - first-line; excludes hemorrhage; early lacunar infarcts may be invisible on CT within the first hours
• MRI DWI/ADC - far more sensitive, shows acute lacunar infarct as bright DWI/dark ADC; preferred when available
• CT angiography - rule out large vessel occlusion (LVO) if deficits are moderate-severe; lacunar strokes rarely have LVO, but it must be excluded
• MRA or CTA - also evaluates for proximal stenosis or cardioembolic source

Step 3 - Acute Reperfusion Therapy

IV Thrombolysis (Alteplase)

• Recommended if presentation is within 4.5 hours of symptom onset and no contraindications, following standard acute ischemic stroke guidelines
• The 2024 ESO Guideline on lacunar ischaemic stroke explicitly recommends IV alteplase for suspected acute lacunar ischaemic stroke per current AIS protocol - Miller's Anesthesia, 10e confirms alteplase within 4.5 h as standard of care
• Dose: 0.9 mg/kg IV (max 90 mg); 10% as bolus over 1 min, remainder over 60 min
• Tenecteplase is an emerging alternative (single bolus, non-inferior in some trials)
• Before giving thrombolysis: lower BP to ≤185/110 mmHg; maintain <180/105 mmHg for ≥24 h post-infusion

Mechanical Thrombectomy

• Generally not indicated for pure lacunar infarcts (no large vessel occlusion target)
• If CTA/MRA reveals an unexpected LVO, apply standard thrombectomy criteria (within 6-24 h with favorable imaging)

Step 4 - Blood Pressure Management (Critical Nuance)

Do NOT aggressively lower BP in the acute phase - this threatens penumbral perfusion

• Agents: IV labetalol (10-20 mg IV bolus) or nicardipine infusion (5-15 mg/h) are preferred in the acute setting
• Hypotension causes: hypovolemia, reduced cardiac output, arrhythmias - treat the underlying cause

Step 5 - Antiplatelet Therapy

• Start aspirin 325 mg within 24-48 h of ictus (after hemorrhage excluded and if no thrombolysis, or after 24-h post-thrombolysis window)
• Dual antiplatelet therapy (DAPT) - aspirin + clopidogrel for 21 days is beneficial for minor stroke/high-risk TIA (POINT and CHANCE trials); then switch to single antiplatelet long-term
• Long-term: single antiplatelet (aspirin or clopidogrel) - ESO 2024 recommends single antiplatelet for secondary prevention
• Anticoagulation is NOT indicated unless a cardioembolic source (e.g., AF) is identified

Step 6 - Watch for Early Neurological Deterioration (END)

• END (NIHSS worsening ≥2 points) occurs in ~23.5% of acute lacunar strokes
• Associated with female sex, hypertension, diabetes, smoking
• 95% of studies reporting END found worse functional outcomes (mRS at 90 days)

• Neuro checks every 1-2 h in the first 24 h
• Any deterioration → emergent repeat CT (rule out hemorrhagic transformation, cerebral edema)
• Cardiac monitoring for ≥24 h (detect paroxysmal AF)
• Post-thrombolysis deterioration: administer cryoprecipitate for suspected bleeding

Step 7 - Supportive Care

Step 8 - Identify and Treat Underlying Cause

• Hypertension - most common culprit; document readings and initiate/optimize antihypertensive before discharge
• Diabetes - optimize glycemic control
• Dyslipidemia - high-intensity statin (atorvastatin 40-80 mg) regardless of baseline LDL; ESO 2024 recommends lipid lowering per current guidelines
• AF - if detected, switch antiplatelet to anticoagulation (DOAC preferred)
• Smoking cessation counseling

Secondary Prevention (Discharge Planning)

• Single antiplatelet (aspirin 75-100 mg/day OR clopidogrel 75 mg/day) long-term
• ACE inhibitor + thiazide diuretic (perindopril-indapamide based on PROGRESS trial) for BP control
• High-intensity statin
• Lifestyle: smoking cessation, regular aerobic exercise, weight control, low-salt diet
• Stroke unit care and early neurorehabilitation

Key Points Summary

1. Treat as a standard acute ischemic stroke until proven otherwise - do NOT withhold alteplase just because the presentation "looks lacunar"
2. Avoid acute BP lowering unless BP >220/120 or pre-thrombolysis
3. DAPT x 21 days for minor stroke, then single antiplatelet long-term
4. Monitor closely for END (~23% incidence) - any deterioration means emergent CT
5. Address hypertension, DM, dyslipidemia, and smoking as the core modifiable drivers

• Bradley and Daroff's Neurology in Clinical Practice - Small-Vessel/Penetrating Artery Disease, p.1364
• Miller's Anesthesia, 10e - Ischemic Stroke, pp.12022-12026
• ESO 2024 Guideline on lacunar ischaemic stroke (Wardlaw et al., PMID 38380638) - Systematic Review / Practice Guideline
• Werring et al. 2025, PMID 39086233 - Systematic review on early neurological deterioration in lacunar stroke