Can a 70-year-old woman with a posterior circulation ischemic stroke presenting with unsteadiness and left-sided weakness (grade 4/5) receive intravenous thrombolysis?

Yes, you can thrombolyse this patient

For a 70-year-old woman with posterior circulation stroke presenting with unsteadiness and 4/5 left-sided weakness within 4.5 hours of symptom onset, intravenous alteplase is recommended unless specific contraindications exist. 1

Key Decision Points

Eligibility Criteria

The 2018 AHA/ASA guidelines provide clear Class I, Level A evidence for IV alteplase (0.9 mg/kg, maximum 90 mg) within 3 hours of symptom onset, and Class I, Level B-R evidence for treatment within 3-4.5 hours 1. Age 70 is not a contraindication—the guidelines explicitly state that benefit is well established "regardless of age and stroke severity" 1.

Posterior Circulation Considerations

The 2024 ESO/ESMINT guidelines on basilar artery occlusion specifically support IVT for posterior circulation strokes within 4.5 hours when there are no contraindications and no extensive ischemic changes 2. The expert consensus (10/10 members) favors IVT in this time window 2.

Critical safety data: Posterior circulation strokes have half the bleeding risk compared to anterior circulation strokes (symptomatic ICH 0.6% vs 1.9% by SITS-MOST criteria) 3. Recent data from the Austrian Stroke Unit Registry confirms treatment benefit within 4.5 hours, with maximum benefit in the first 2 hours and a transition point at 258 minutes 4.

Severity Assessment

Your patient's presentation (4/5 weakness with unsteadiness) suggests a disabling stroke—this is precisely the population where IV alteplase shows proven benefit 1. The mild-to-moderate severity actually favors treatment, as posterior circulation strokes typically present with lower NIHSS scores but still benefit from thrombolysis 3.

Common Pitfalls to Avoid

1. Don't withhold treatment based on "mild" symptoms: Unsteadiness with hemiparesis is disabling and warrants treatment
2. Don't delay for extensive imaging: If within 4.5 hours and no contraindications on non-contrast CT, proceed
3. Check for posterior circulation ASPECTS ≥8: Extensive early ischemic changes would be a relative contraindication 2
4. Verify absolute contraindications from Table 6 in the AHA guidelines 1:
   • Blood glucose <60 mg/dL (treat first)
   • Blood pressure ≥185/110 mmHg (lower first to <185/110)
   • Recent surgery, bleeding, or anticoagulation issues

Treatment Protocol

• Dose: 0.9 mg/kg (maximum 90 mg) over 60 minutes with 10% as initial bolus over 1 minute 1
• Blood pressure target: Maintain <180/105 mmHg during and for 24 hours after treatment 1
• Blood glucose: Keep 140-180 mg/dL 1
• Time is critical: Each 30-minute delay reduces probability of functional independence by 2.6% 4

Gender Consideration

Note that women have lower IVT rates overall (11.3% vs 13.0%) but achieve similar functional outcomes to men when treated 4. Don't let gender bias delay appropriate treatment.

The evidence strongly supports thrombolysis in this scenario, with posterior circulation strokes showing better safety profiles than anterior circulation strokes and functional independence rates of 45-61% at 3 months 3, 5.