Late-Window Large Vessel Occlusion in a Patient Who Recently Took a Factor Xa Inhibitor
A 74-year-old woman with atrial fibrillation on apixaban, last dose 10 hours ago, is found on the floor at 6:00 a.m. by her daughter; she was seen normal at 10:00 p.m. the previous night. She has global aphasia, right gaze preference, and dense right hemiplegia, NIHSS 15. Noncontrast CT shows no hemorrhage and an ASPECTS of 8. CTA shows a left M1 occlusion. CT perfusion shows a core of 20 mL and a Tmax greater than 6 seconds volume of 95 mL. Blood pressure is 178/96 mm Hg, glucose 118 mg/dL, weight 70 kg, and creatinine clearance 62 mL/min. She lives alone and was independent in all activities of daily living. The stroke team is divided on whether she should receive intravenous thrombolysis while the angiography suite is prepared.
1. Should she receive intravenous thrombolysis? Walk through the competing considerations and state your decision with its justification.
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Decision: no intravenous thrombolytic; proceed directly to thrombectomy.
Time is not the deciding issue. She is roughly 8 hours from last known well, and if she woke from sleep the midpoint of the sleep period would place her even earlier. Perfusion-mismatch trials support reperfusion therapy in this time frame, so "outside the window" is not by itself disqualifying.
The anticoagulant is the deciding issue. Apixaban taken 10 hours earlier means meaningful residual factor Xa inhibition. Current labeling and guidelines treat a direct oral anticoagulant taken within 48 hours as a contraindication to intravenous alteplase or tenecteplase. Normal coagulation studies do not reliably exclude residual effect with a factor Xa inhibitor, and reversal with andexanet specifically to permit thrombolysis is not established and would add thrombotic risk without proven benefit.
She clearly meets thrombectomy criteria: anterior circulation occlusion, NIHSS 15, core 20 mL with a penumbra of 75 mL, mismatch ratio 4.75, and prestroke independence. The benefit of thrombectomy in this profile is large and does not depend on prior thrombolysis.
Practical corollary: do not let the lytic debate delay groin puncture, and do not transfuse or reverse the apixaban for the sole purpose of giving a lytic when mechanical reperfusion is available.
2. Set out your blood pressure targets before, during, and after the procedure, and justify the upper and lower bounds.
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Before and during the procedure: keep systolic below 185 mm Hg and diastolic below 110 mm Hg - the threshold at which the patient becomes eligible under standard reperfusion criteria - but do not overshoot. A systolic in the 150–180 mm Hg range is generally acceptable and even desirable, because during an M1 occlusion the penumbra is perfused through collaterals that are pressure-passive. A sharp drop at induction of anesthesia or with a single intravenous bolus can convert penumbra into core before recanalization. Use a nicardipine infusion rather than intermittent boluses, and avoid hypotension (systolic below 100 mm Hg or a fall of more than 20% from baseline) at all times.
After successful reperfusion: target systolic below 180/105 mm Hg per guidelines, but resist the urge to push much lower. Three randomized trials of intensive lowering after endovascular therapy (BEST-II targeting below 140, OPTIMAL-BP targeting below 140, and ENCHANTED2/MT targeting below 120) showed no benefit and signals of harm, including worse functional outcomes. The pressure that was protective during occlusion can become a liability once the vessel is open, so the goal is moderate control, not the lowest tolerated number.
If reperfusion fails or is incomplete: continue permissive hypertension with systolic below 185 mm Hg, since collateral dependence persists.
3. Describe your plan for antithrombotic therapy over the next two weeks. What determines the timing of anticoagulation restart, and what pitfalls do you want to avoid?
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First 24 hours: no thrombolytic was given, so antiplatelet therapy is not precluded. Obtain post-procedure imaging and start aspirin once hemostasis is confirmed and there is no significant hemorrhagic transformation. Mechanical thrombectomy alone is not a reason to withhold early antiplatelet therapy.
Restarting anticoagulation: the dominant variable is infarct size and hemorrhagic transformation risk, not the presence of atrial fibrillation alone. With a 20 mL core and a moderate completed infarct, restarting apixaban in roughly the 2–5 day range is reasonable after repeat imaging shows stability; a very small infarct might justify earlier restart, and a large confluent infarct with petechial hemorrhage might justify deferral toward 7–14 days. Recent randomized data and meta-analyses suggest early direct oral anticoagulant resumption is not inferior to delayed resumption, so a rigid two-week wait is not required.
Pitfalls:
- Do not bridge with therapeutic heparin or low-molecular-weight heparin "while awaiting" the oral agent; bridging increases bleeding without reducing stroke.
- Do not use dual antiplatelet therapy as a substitute for anticoagulation in atrial fibrillation.
- Do not miss the opportunity to document the rhythm, arrange adherence support, and address the fact that she lives alone and may have taken a delayed or missed dose - the dose history matters for both the lytic decision and the restart plan.
- Reassess renal function before finalizing the apixaban dose.