Management of Acute Ischemic Stroke with Proximal Anterior Circulation Occlusion at 12 Hours
This patient requires combined intravenous tPA and mechanical thrombectomy immediately, as they present within the extended window (up to 24 hours) with a small to moderate ischemic core and proximal anterior circulation occlusion—criteria that define salvageable brain tissue. 1
Why Combined Therapy is the Standard of Care
Mechanical thrombectomy plus IV tPA is superior to either therapy alone for proximal anterior circulation occlusions with salvageable tissue. The evidence is unequivocal:
The ESCAPE trial demonstrated that rapid endovascular treatment plus standard care (which included IV tPA in 91.5% of patients) achieved functional independence in 53.0% versus 29.3% with standard care alone (common odds ratio 2.6, P<0.001), with reduced mortality (10.4% vs 19.0%) 2
The MR CLEAN trial showed that 83.7% of patients in the intervention arm received IV tPA alongside mechanical thrombectomy, with an adjusted common odds ratio of 1.67 favoring the combined approach 3
At 12 hours post-onset, patients remain within the 24-hour window for mechanical thrombectomy when imaging demonstrates salvageable tissue, as established by multiple guidelines 4, 1
Critical Imaging Confirmation Required
Before proceeding, you must verify the patient meets salvageable tissue criteria:
- DAWN criteria: 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
- ASPECTS score must be >0 on non-contrast CT, as ASPECTS of 0 is an absolute contraindication 1
The patient's "small to moderate ischemic core" description suggests they meet these criteria, but advanced perfusion imaging should confirm salvageable penumbra 1.
Why Not TPA Alone?
IV tPA alone is inadequate for proximal anterior circulation occlusions:
- Proximal large vessel occlusions (ICA, M1) have dismal natural history outcomes, with only 38.5% achieving functional independence and 23.1% mortality at 6 months without mechanical intervention 5
- Patients with baseline NIHSS ≥10 and proximal occlusions achieve functional independence in only 7.1-23.5% without thrombectomy 5
Why Not Thrombectomy Alone?
The landmark trials that established thrombectomy efficacy used combined therapy as the standard:
- 89.0% of MR CLEAN patients received IV alteplase before randomization 3
- Subgroup analyses consistently show benefit when IV tPA is added to mechanical thrombectomy 1
Technical Execution
Minimize door-to-groin puncture time—the ESCAPE trial achieved median groin puncture at 110 minutes, and the median time from CT to first reperfusion was 84 minutes 2:
- Administer IV tPA immediately while preparing for thrombectomy (do not delay tPA for thrombectomy preparation) 4, 1
- Use stent retrievers (used in 81.5% of MR CLEAN cases) to achieve TICI 2b/3 reperfusion 1, 3
- Target TICI 2b/3 recanalization (achieved in 59% of MR CLEAN patients) 1
Critical Contraindications to Avoid
Do not proceed if:
- ASPECTS score is 0 1
- No perfusion mismatch on advanced imaging 1
- Large established infarct core >70 mL by DEFUSE-3 criteria 1
- Patient does not meet DAWN or DEFUSE-3 criteria 1
Post-Procedure Management
- Maintain blood pressure ≤180/105 mmHg for 24 hours post-thrombectomy to reduce hemorrhagic transformation risk 1
- Monitor closely for symptomatic intracerebral hemorrhage (occurred in 3.6% of ESCAPE intervention patients) 2
- Assess for compartment syndrome if there was any limb ischemia component 1
Common Pitfall
Do not delay treatment for unnecessary testing beyond confirming blood glucose and obtaining vascular imaging. The normal coagulation profile and platelet count already provided are sufficient—additional laboratory work should not delay therapy 1.