What are the interventions for a left Middle Cerebral Artery (MCA) infarct?

Interventions for Left MCA Infarct

Decompressive craniectomy with dural expansion is the most effective intervention for patients with malignant left MCA infarction who deteriorate neurologically within 48 hours despite medical therapy, as it reduces mortality by approximately 50% and improves functional outcomes, particularly in patients ≤60 years of age. 1

Early Identification and Risk Assessment

Early identification of patients at risk for malignant MCA infarction is crucial for timely intervention:

• Clinical predictors of malignant course include NIHSS >20 for left MCA infarcts, nausea/vomiting, and progressive neurological deterioration 1
• Radiological predictors include hypodensity >50% of the MCA territory on initial CT, early midline shift, and involvement of additional vascular territories 1
• MRI diffusion-weighted imaging within 6 hours showing infarct volumes ≥80 mL predict a rapid fulminant course 1

Triage and Management

Immediate Measures

• Transfer patients with signs of large MCA infarction to a center with neurosurgical expertise and neuromonitoring capabilities 1
• Obtain early neurosurgical consultation to facilitate planning for potential decompressive surgery 1
• Implement initial medical management to limit brain swelling:
  • Restrict free water to avoid hypo-osmolar fluid 1
  • Correct factors that exacerbate swelling (hypoxemia, hypercarbia, hyperthermia) 1
  • Elevate head of bed 20-30° to help venous drainage 1
  • Avoid antihypertensive agents that cause cerebral vasodilation 1

Medical Management

• Osmotic therapy is reasonable for patients with clinical deterioration from cerebral swelling 1
  • Mannitol: 0.25-0.5 g/kg IV over 20 minutes every 6 hours (maximum dose 2g/kg) 1
  • Target serum osmolarity of 315-320 mOsm/L 2
• Brief moderate hyperventilation (PCO2 target 30-34 mmHg) can be used as a bridge to more definitive therapy 1
• Note: Hypothermia or barbiturates are not recommended for ischemic cerebral swelling 1

Surgical Intervention

• For patients ≤60 years with unilateral MCA infarction who deteriorate within 48 hours:

  • Decompressive craniectomy with dural expansion reduces mortality by approximately 50% 1
  • 55% of surgical survivors achieve moderate disability (able to walk) or better (mRS 2-3) 1
  • 18% achieve independence (mRS 2) at 12 months 1

• For patients >60 years with unilateral MCA infarction who deteriorate within 48 hours:

  • Decompressive craniectomy may be considered as it reduces mortality by approximately 50% 1
  • However, functional outcomes are worse than in younger patients, with only 11% achieving moderate disability (mRS 3) and none achieving independence (mRS ≤2) at 12 months 1

• Surgical technique:

  • Large bone flap including frontal, temporal, and parietal bones with diameter of at least 120 mm 1
  • Extend craniectomy down to temporal skull base 1
  • Open dura widely in cruciate fashion 1
  • Cover cortical surface with unapproximated dural flaps 1

Important Considerations and Caveats

• Decrease in level of consciousness attributed to brain swelling is a reasonable trigger for decompressive craniectomy 1
• The optimal timing for intervention is within 48 hours of stroke onset, before severe neurological deterioration occurs 1
• Left MCA infarcts often involve language centers, which may result in aphasia even with successful intervention 1
• Despite aggressive management, mortality remains high (approximately 50-70%) with medical management alone 1
• Hemorrhagic transformation is a common complication of severe stroke and may complicate management 1
• For patients with cerebellar infarction with swelling, decompressive suboccipital craniotomy should be performed to remove necrotic tissue 1

Follow-up Care

• After decompressive surgery, patients require intensive care unit monitoring 1
• When discharged, patients should use a custom-fitted protective helmet until cranioplasty 1
• Cranioplasty can be scheduled when there are no signs of persisting brain swelling (typically 12-16 weeks after discharge) 1