What is the most appropriate management for a patient with 12 hours of lower limb weakness, normal vitals, normal coagulation profile, normal platelet count, small to moderate ischemic core, and proximal anterior circulation occlusion?

Management of Acute Ischemic Stroke with Proximal Anterior Circulation Occlusion at 12 Hours

For this patient presenting at 12 hours with a small to moderate ischemic core and proximal anterior circulation occlusion, the most appropriate management is combined tPA and mechanical thrombectomy (Option C), provided the patient meets specific imaging criteria for salvageable tissue. 1

Rationale for Combined Therapy

The patient falls within the extended treatment window (6-24 hours) where mechanical thrombectomy is strongly indicated based on tissue viability rather than time alone. 1, 2

• The ESCAPE trial specifically enrolled patients up to 12 hours from onset with small infarct cores (ASPECTS ≥6) and proximal anterior circulation occlusions, demonstrating significant benefit with endovascular treatment (adjusted OR 1.67 for improved functional outcomes). 1

• At 12 hours, this patient is beyond the standard 4.5-hour window for tPA alone but well within the extended window for mechanical thrombectomy when salvageable tissue is present. 1

Critical Imaging Requirements at This Time Point

Advanced perfusion imaging is essential to confirm salvageable tissue before proceeding with treatment at 12 hours. 1, 3, 2

• The patient must demonstrate either:

  • DAWN criteria: Clinical-imaging mismatch (age <80 years with NIHSS ≥10 and core <31 mL, OR NIHSS ≥20 and core <51 mL) 1
  • DEFUSE-3 criteria: Ischemic core <70 mL, mismatch ratio ≥1.8, and mismatch volume ≥15 mL 1

• The description of "small to moderate ischemic core" suggests the patient likely meets these criteria, making thrombectomy appropriate. 3

Why Combined Therapy Over Thrombectomy Alone

Most patients in the positive thrombectomy trials (83.7% in MR CLEAN, 91.5% in ESCAPE) received IV tPA in addition to mechanical thrombectomy, and subgroup analyses showed benefit in this combined approach. 1

• The MR CLEAN trial demonstrated that 445 of 500 patients received IV tPA and showed benefit, though there were too few patients without tPA to draw definitive conclusions. 1

• If the patient is within 4.5 hours of symptom onset, tPA should be administered without delay while preparing for thrombectomy. However, at 12 hours, tPA alone is contraindicated, but it may still be considered as adjunctive therapy during the thrombectomy procedure at the interventionalist's discretion. 1

Why Not Observation (Option D)

Observation is inappropriate given the proven mortality and morbidity benefit of mechanical thrombectomy in this clinical scenario. 1, 2

• The DAWN trial showed a 35.5% absolute increase in functional independence with thrombectomy versus medical management alone at extended time windows (median 12.5 hours). 2

• DEFUSE-3 demonstrated a 28% increase in functional independence and 20% absolute reduction in death or severe disability with thrombectomy at median 11 hours. 2

• The number needed to treat with mechanical thrombectomy to reduce disability by one level on the modified Rankin Scale is only 2.6. 2

Technical Considerations

The goal of mechanical thrombectomy should be TICI 2b/3 reperfusion to maximize functional outcomes. 3, 4

• Stent retrievers were used in 81.5% of cases in MR CLEAN with 59% achieving TICI 2b/3 recanalization. 1

• The ESCAPE trial emphasized minimizing door-to-groin puncture time (target within 60 minutes of imaging), with median groin puncture time of 110 minutes. 1

Critical Pitfalls to Avoid

Do not delay treatment for unnecessary testing beyond confirming blood glucose and obtaining essential vascular imaging. 3

• The patient's normal coagulation profile and platelet count have already been confirmed, eliminating contraindications. 1

Do not proceed with thrombectomy if imaging shows:

• ASPECTS of 0 (extensive irreversible damage) 3
• No perfusion mismatch (no salvageable tissue) 3
• Large established infarct core (>70 mL by DEFUSE-3 criteria or not meeting DAWN criteria) 1, 3

Post-Procedure Management

Maintain blood pressure ≤180/105 mmHg for 24 hours after thrombectomy to optimize outcomes and reduce hemorrhagic complications. 4, 5

• Recent evidence suggests maintaining even lower BP targets (<140 mmHg systolic) after successful reperfusion may be beneficial, though guidelines currently recommend <180/105 mmHg. 4, 5

Monitor closely for compartment syndrome and hemorrhagic transformation in the immediate post-procedure period. 4