What's the most appropriate management for a patient with a 12-hour history of lower limb weakness, now asymptomatic, with normal vitals, coagulation profile, and platelet count, and imaging showing a small to moderate ischemic core and proximal anterior circulation occlusion?

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

This patient requires combined intravenous tPA and mechanical thrombectomy (Option C), as the presence of a small to moderate ischemic core with proximal anterior circulation occlusion at 12 hours meets criteria for extended-window intervention based on tissue viability rather than time alone. 1

Why Combined Therapy is Indicated

The American Heart Association specifically recommends combined tPA and mechanical thrombectomy for patients with proximal anterior circulation occlusion and a small to moderate ischemic core when salvageable tissue is demonstrated, even beyond traditional time windows. 1 This recommendation is based on:

• 83.7% of patients in the MR CLEAN trial and 91.5% in the ESCAPE trial received IV tPA in addition to mechanical thrombectomy, with subgroup analyses demonstrating benefit in this combined approach. 2, 1

• The ESCAPE trial specifically enrolled patients up to 12 hours from onset and demonstrated an adjusted odds ratio of 1.67 (95% CI, 1.21-2.30) favoring combined intervention over usual care alone, with an absolute difference of 13.5% in functional independence. 2

• 445 of 500 patients in MR CLEAN received IV tPA alongside thrombectomy, establishing this as the evidence-based standard rather than thrombectomy alone. 2, 1

Critical Imaging Requirements Already Met

Your patient's imaging demonstrates the essential criteria for proceeding:

• Small to moderate ischemic core indicates salvageable tissue, which is the primary determinant for treatment eligibility at 12 hours, not the time window itself. 1

• Proximal anterior circulation occlusion is specifically the target lesion for mechanical thrombectomy, as intravenous thrombolysis alone is less efficacious for proximal thrombus. 2

• Advanced perfusion imaging should confirm either DAWN criteria (clinical-imaging mismatch) or DEFUSE-3 criteria (ischemic core <70 mL, mismatch ratio ≥1.8, mismatch volume ≥15 mL) before proceeding. 1

Why Not the Other Options

Option A (tPA alone) is inadequate because intravenous thrombolysis achieves recanalization rates of less than 50% for proximal large-vessel occlusions, and this patient is beyond the 4.5-hour window where tPA monotherapy is standard. 3, 4

Option B (manual embolectomy alone) contradicts the evidence, as the vast majority of positive thrombectomy trials included IV tPA administration, and withholding tPA when not contraindicated removes a proven beneficial component. 2, 1

Option D (observation) is inappropriate because the patient has documented proximal vessel occlusion with salvageable tissue—the exact scenario where intervention prevents permanent disability, regardless of current symptom resolution. 2 Transient symptom improvement does not indicate spontaneous recanalization and should not delay definitive treatment.

Technical Execution

Minimize door-to-groin puncture time, targeting the ESCAPE trial benchmark of 110 minutes median time, though your patient's 12-hour presentation allows some flexibility given the extended window. 1

Use stent retrievers as the primary thrombectomy device, which achieved 81.5% utilization in MR CLEAN with 59% achieving TICI 2b/3 recanalization. 2, 1

The goal is TICI 2b/3 reperfusion to maximize functional outcomes. 1

Critical Pitfalls to Avoid

Do not delay treatment to obtain unnecessary additional testing beyond confirming blood glucose and completing essential vascular imaging. 1 Your patient already has normal coagulation profile and platelet count, which addresses the primary contraindications.

Do not proceed if repeat imaging shows ASPECTS of 0, no perfusion mismatch, or large established infarct core >70 mL, as these indicate non-salvageable tissue. 1

The patient's current asymptomatic status is misleading—proximal vessel occlusion with salvageable tissue requires intervention regardless of transient symptom fluctuation, as early neurological improvement trajectories do not reliably predict outcomes without recanalization. 5

Post-Intervention Management

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

Monitor closely for hemorrhagic transformation, as symptomatic intracerebral hemorrhage occurs in approximately 6% of tPA-treated patients, though this risk is acceptable given the 13.5% absolute improvement in functional independence. 2