What is the appropriate treatment for an acute posterior circulation stroke presenting with vertigo?

Treatment of Acute Posterior Circulation Stroke Presenting with Vertigo

For patients with acute posterior circulation stroke presenting with vertigo, endovascular thrombectomy is indicated for basilar artery occlusion within 12 hours (and reasonable up to 24 hours) when NIHSS ≥6 and PC-ASPECTS ≥6, while intravenous alteplase should be administered within 4.5 hours for patients without contraindications and without extensive ischemic changes. 1, 2

Endovascular Thrombectomy for Large Vessel Occlusion

Within 12 Hours (Class I Recommendation)

• Thrombectomy is definitively indicated for basilar artery occlusion (BAO) patients meeting these criteria: 1
  • NIHSS score ≥6
  • PC-ASPECTS ≥6 on imaging
  • Age 18-89 years
  • Within 12 hours of last known well

12-24 Hour Window (Class IIa Recommendation)

• Thrombectomy remains reasonable for BAO patients presenting between 12-24 hours with NIHSS ≥6 and PC-ASPECTS ≥6 1
• This recommendation is based on the BAOCHE and ATTENTION trials demonstrating superiority of thrombectomy over medical therapy alone 1

Beyond 24 Hours (Class IIb Recommendation)

• Thrombectomy may be considered on a case-by-case basis for BAO patients beyond 24 hours, though outcomes are universally poor when NIHSS ≤6 1
• Successful recanalization has been achieved in 50% of patients treated beyond 24 hours in case series, though benefit remains uncertain 1

Intravenous Thrombolysis

Standard Time Window (<4.5 Hours)

• For patients presenting within 4.5 hours without contraindications and without extensive posterior circulation ischemic changes (PC-ASPECTS ≥8), intravenous alteplase is strongly recommended 1
• The European Stroke Organisation expert consensus (10/10 members) supports IVT in this population despite lack of randomized data specific to BAO 1
• Meta-analysis data shows 77% achieve favorable functional outcomes (mRS 0-2) when treated in the standard window, with only 4% symptomatic intracranial hemorrhage rate 3

Extended Time Window (4.5-24 Hours)

• Recent breakthrough evidence from the EXPECTS trial demonstrates that alteplase administered 4.5-24 hours after posterior circulation stroke onset results in significantly higher functional independence (89.6% vs 72.6%) compared to standard care 2
• This applies specifically to patients with mainly mild posterior circulation strokes (median NIHSS 3) without extensive early hypodensity on CT and no planned thrombectomy 2
• Symptomatic intracranial hemorrhage risk remains low at 1.7% in the extended window 2

Special Considerations for Vertigo Presentations

Clinical Decision-Making Challenges

• Patients presenting with acute vestibular syndrome (AVS) or acute imbalance syndrome (AIS) pose diagnostic challenges, as only 45.7% of evaluated patients meet AVS criteria and 23.7% meet AIS criteria 4
• Key factors that guide decision-making toward IVT in dizzy patients include: 5
  • Disabling vestibular symptoms (severe dizziness/vertigo, inability to stand unsupported)
  • Central oculomotor signs
  • Mild focal neurological abnormalities
  • Hypoperfusion on perfusion CT imaging

Timing Considerations

• Door-to-needle time may be significantly longer for posterior circulation strokes compared to anterior circulation (90±29 min vs 74±30 min), likely due to diagnostic uncertainty 4
• However, when AVS/AIS patients are identified as stroke candidates, DNT can be comparable to other posterior circulation presentations (70±39 min) 4

Perfusion Imaging Role

• Perfusion CT was performed in 80% of IVT-treated AVS/AIS patients versus 0% of non-treated patients in one series 5
• When comparing initial hypoperfusion to final infarct size, IVT-related tissue salvage was demonstrated in 3 of 7 patients 5

Safety Profile

Hemorrhagic Risk

• No symptomatic intracranial hemorrhages occurred in small cohorts of AVS/AIS patients treated with IVT 5
• Overall pooled sICH rate for posterior circulation IVT is 4% (95% CI: 0.02-0.07), lower than anterior circulation 3
• Extended window treatment (4.5-24 hours) shows acceptable safety with 1.7% sICH rate 2

Mortality Outcomes

• Overall 90-day mortality after IVT for posterior circulation stroke is 19% 3
• Mortality is significantly lower when treated in standard versus extended time window (RR=0.42) 3
• The EXPECTS trial showed 5.2% mortality with alteplase versus 8.5% with standard care at 90 days 2

Common Pitfalls to Avoid

• Do not withhold IVT from posterior circulation stroke patients solely based on presentation with isolated vertigo - central oculomotor signs and focal deficits should prompt aggressive workup 1, 4
• Do not assume all dizzy patients are benign peripheral vestibulopathy - up to 50% of BAO patients can achieve favorable outcomes with appropriate treatment when PC-ASPECTS ≥8 1
• Do not delay thrombectomy evaluation beyond 24 hours without consideration - case-by-case assessment may still identify candidates for intervention 1