What is the golden period for ischemic stroke treatment?

Golden Period of Ischemic Stroke

The golden period for ischemic stroke treatment is the first 60 minutes after symptom onset, during which intravenous thrombolysis provides maximum benefit with the best functional outcomes. 1, 2

Time Windows for Treatment

The Golden Hour (0-60 minutes)

• Treatment within the first 60 minutes after stroke onset yields the most dramatic benefits, with patients achieving a median NIHSS of 0 at discharge regardless of age or comorbidities 3
• Golden hour thrombolysis increases odds of excellent functional outcomes (mRS 0-1) by 40% compared to later treatment (OR 1.40,95% CI 1.16-1.67) 2
• The number needed to treat within the golden hour to reduce disability by at least 1 level on the modified Rankin Scale is only 2.6 patients 2
• Patients treated within 60 minutes have significantly higher rates of discharge to home (adjusted OR 1.25), independent ambulation (adjusted OR 1.22), and freedom from disability (adjusted OR 1.72) compared to those treated 61-270 minutes after onset 4

Standard Treatment Window (0-3 hours)

• The American Heart Association establishes the traditional window for intravenous rtPA as within 3 hours of symptom onset, with Class I recommendation 5, 1
• Treatment within 90 minutes yields an OR of 2.11 for favorable outcomes, while 90-180 minutes yields an OR of 1.69 5
• The benefit declines progressively with time, with more rapid benefit loss in the first 170 minutes 4

Extended Window (3-4.5 hours)

• The treatment window can be extended to 3-4.5 hours for carefully selected patients (Class I Recommendation, Level of Evidence B) 5, 1
• The ECASS-3 trial demonstrated 52.4% of patients achieved mRS 0-1 when treated in this window versus 45.2% with placebo (OR 1.34) 5
• Additional exclusion criteria apply: age >80 years, oral anticoagulant use, baseline NIHSS >25, and combination of prior stroke plus diabetes 5, 1

Beyond 4.5 Hours

• For basilar artery occlusion specifically, endovascular therapy can be considered 6-24 hours from last known well in selected patients 5
• Treatment beyond 4.5-6 hours for anterior circulation strokes shows diminishing benefit (OR 1.15) and increased mortality risk 5

Critical Clinical Implications

Why Time Matters

• Every minute of delay results in loss of 1.9 million brain cells, 13.8 billion synapses, and 12 km of axonal fibers 5
• Each hour without treatment causes brain aging equivalent to 3.6 years of normal aging 5
• The risk-benefit ratio changes over time, with symptomatic intracerebral hemorrhage rates of 7.9% in the 3-4.5 hour window versus 3.5% with placebo 5, 1

Optimizing the Treatment Chain

• "Last known well time" is the single most important determinant of treatment eligibility and must be established immediately by EMS personnel 5
• Prehospital notification of the receiving hospital is imperative to ensure stroke teams are ready when the patient arrives 5
• Door-to-needle times must be minimized, with systematic improvements demonstrating the ability to increase golden hour treatments from 2.2% to 18.3% of all thrombolysis cases 3

Common Pitfalls to Avoid

• Do not delay treatment to obtain "perfect" imaging - the clock is ticking and standard CT is sufficient to exclude hemorrhage and proceed with thrombolysis in appropriate candidates 5
• Do not dismiss patients with "minor" or "rapidly improving" symptoms - these patients may still benefit from treatment within the golden hour, though this represents off-label use 5
• Do not forget that symptom onset time means "last known well" - if the patient woke up with symptoms, use the time they went to sleep 5
• Do not administer glucose-containing fluids unless the patient is hypoglycemic - this can worsen outcomes 5