What is the best management approach for a patient presenting with right-sided weakness due to a proximal anterior circulation occlusion and a moderate-sized infarct core, 12 hours after symptom onset?

Management of Acute Ischemic Stroke at 12 Hours with Proximal Anterior Circulation Occlusion and Moderate Infarct Core

The optimal management is combined tPA and mechanical thrombectomy (Option D), provided the patient meets specific imaging criteria demonstrating salvageable tissue despite the moderate infarct core. 1

Why Combined Therapy is Superior at 12 Hours

Combined tPA and mechanical thrombectomy should be administered in parallel when salvageable tissue is confirmed on advanced imaging, as this approach maximizes functional outcomes and reduces mortality compared to either therapy alone or observation. 1, 2

Evidence Supporting Combined Therapy

• The American Heart Association recommends combined tPA and mechanical thrombectomy for patients with proximal anterior circulation occlusion and small to moderate ischemic cores, with treatment decisions based on tissue viability rather than time alone 1

• In the landmark ESCAPE trial, 91.5% of patients received IV tPA alongside mechanical thrombectomy, demonstrating that combined therapy is the standard approach that produced the positive trial results 1, 2

• The adjusted odds ratio for improved functional outcomes with combined therapy versus medical management alone is 1.67 (95% CI 1.21-2.30), indicating significant benefit 2

• Among patients with proximal vessel occlusion in the anterior circulation, 60-80% die or fail to regain functional independence with alteplase alone, making mechanical thrombectomy essential 3

Critical Imaging Requirements Before Proceeding

You must obtain advanced perfusion imaging (CT perfusion or MRI with diffusion-perfusion mismatch) to confirm salvageable tissue before initiating treatment at 12 hours. 1

Specific Imaging Criteria to Meet

The patient must satisfy either:

DAWN Criteria:

• Age <80 years with NIHSS ≥10 and infarct core <31 mL, OR
• NIHSS ≥20 and infarct core <51 mL 1

DEFUSE-3 Criteria:

• Ischemic core <70 mL
• Mismatch ratio ≥1.8
• Mismatch volume ≥15 mL 1

Absolute Contraindications to Thrombectomy

Do not proceed if imaging demonstrates:

• ASPECTS score of 0
• No perfusion mismatch
• Large established infarct core >70 mL by DEFUSE-3 criteria
• Failure to meet DAWN criteria 1

Technical Implementation Strategy

Workflow Optimization

Administer IV tPA immediately while simultaneously mobilizing the interventional team—do not wait to assess clinical response to tPA before proceeding to thrombectomy. 2

• Door-to-groin puncture time should be minimized to <110 minutes from arrival 1, 2
• Every 30-minute delay reduces the probability of favorable outcome by approximately 10.6% 2
• The median time from CT to first reperfusion in ESCAPE was 84 minutes, which should be your target 3

Procedural Details

• Use stent retrievers as the preferred device, which achieve TICI 2b/3 recanalization in 59-87.8% of cases 2
• Target TICI 2b/3 reperfusion to maximize functional outcomes 1
• Prefer procedural sedation over general anesthesia unless airway compromise or severe agitation necessitates intubation 2

Why Not the Other Options

Option A (tPA alone): IV alteplase achieves recanalization in less than 50% of large vessel occlusions, with particularly poor results in proximal occlusions like M1 segments 2. At 12 hours, tPA alone is outside the standard 4.5-hour window and would be inadequate for a proximal occlusion with moderate core 1.

Option B (Mechanical thrombectomy alone): While thrombectomy is the definitive intervention, withholding tPA contradicts the evidence from positive trials where 83.7-91.5% of patients received IV thrombolytics alongside mechanical intervention 1, 2. Additionally, IV alteplase was associated with a 68% reduction in the odds of infarct in new territory (3.0% with versus 9.1% without; OR 0.32,95% CI 0.11-0.96) 4.

Option C (Observation): This is unacceptable given that rapid endovascular treatment improved functional outcomes (53.0% vs 29.3% functional independence) and reduced mortality (10.4% vs 19.0%) compared to standard care alone in the ESCAPE trial 3.

Post-Procedure Management

Maintain blood pressure ≤180/105 mmHg for 24 hours after thrombectomy to optimize outcomes and reduce hemorrhagic complications. 1

• Monitor closely for compartment syndrome and hemorrhagic transformation in the immediate post-procedure period 1
• Symptomatic intracerebral hemorrhage occurs in approximately 3.6% of patients receiving combined therapy 3

Common Pitfalls to Avoid

Critical Error #1: Delaying treatment for unnecessary testing beyond confirming blood glucose and obtaining essential vascular imaging 1

Critical Error #2: Waiting to assess clinical response to IV tPA before mobilizing for thrombectomy—both treatments must proceed in parallel 2

Critical Error #3: Proceeding without advanced perfusion imaging at 12 hours, as tissue viability (not time alone) determines eligibility in the extended window 1

Critical Error #4: Assuming the moderate infarct core is a contraindication—patients with ASPECTS 3-5 now have evidence supporting endovascular treatment with numbers needed to treat of 4.7 for better functional outcomes 2