What are the contraindications for thrombolysis in acute ischemic cerebrovascular accident (stroke)?

Contraindications for Thrombolysis in Acute Ischemic Stroke

The 2026 AHA/ASA guidelines have significantly liberalized thrombolysis contraindications, shifting from rigid exclusion criteria to a more nuanced risk-benefit assessment for individual patients 1.

Absolute Contraindications (True Hard Stops)

The following remain absolute contraindications where thrombolysis should NOT be given:

• Active internal bleeding at time of presentation
• Intracranial hemorrhage on baseline imaging
• Suspected subarachnoid hemorrhage (even if CT negative)
• Severe uncontrolled hypertension (systolic BP >185 mmHg or diastolic >110 mmHg) that cannot be safely lowered
• Known intracranial arteriovenous malformation, aneurysm, or neoplasm with high bleeding risk
• Acute bleeding diathesis including:
  • Platelet count <100,000/mm³
  • INR >1.7 on warfarin
  • aPTT elevated with heparin use
  • Direct thrombin or factor Xa inhibitors with elevated sensitive lab assays

Relative Contraindications (Now Reconsidered)

Many traditional "contraindications" are now considered relative, where treatment may proceed after careful risk-benefit analysis 2, 1:

Age-Related

• Age >80 years is NO LONGER a contraindication - Multiple studies demonstrate equal benefit in elderly patients, particularly when treated within 3 hours 3, 2. The adjusted odds ratio for favorable outcome is 1.40 (95% CI 1.14-1.70) in patients >80 years 2.

Stroke Severity

• Minor stroke or rapidly improving symptoms - Previously excluded, but recent evidence shows these patients may still benefit, especially with large vessel occlusion on imaging 4, 5. The 2026 guidelines support treatment in this population 1.
• Severe stroke (NIHSS >22) - Can be treated with adjusted OR 1.57 (95% CI 1.12-2.18) for better outcomes 2.

Medical History

• Prior stroke PLUS diabetes - Can be treated with OR 1.50 (95% CI 1.03-2.18) 2
• Recent stroke (<3 months) - The 2026 guidelines have relaxed this restriction; case reports show successful treatment even within 48 hours of prior stroke 6, 1
• Prior antiplatelet therapy - Single agent shows OR 1.42 (95% CI 1.19-1.70) for benefit 2
• Oral anticoagulation with INR ≤1.7 - Can be treated with OR 2.20 (95% CI 1.12-4.32) 2

Recent Procedures

• Recent lumbar puncture (<7 days) - Previously absolute, now relative; successful treatment reported within 24 hours 6
• Recent surgery (<14 days) - Evaluate bleeding risk individually
• History of AAA repair - Only 6% rupture rate in one series; consider abdominal CTA if time permits but don't delay treatment 7

Laboratory Values

• Glucose >180 mg/dL (>10 mmol/L) - Can be treated with OR 1.50 (95% CI 1.15-1.97) 2. The 2026 guidelines emphasize hyperglycemia management but don't exclude treatment 1.

Time Windows

Standard window: 0-4.5 hours from symptom onset 8, 5, 3

• Treatment within 3 hours shows substantially greater benefit (OR 0.66,95% CI 0.56-0.79) without increased mortality 3
• Treatment between 3-4.5 hours still beneficial but less robust (OR 0.85,95% CI 0.78-0.93) 3

Wake-up stroke with DWI-FLAIR mismatch: Extended window possible 5

• High quality evidence supports treatment in selected patients with MRI mismatch pattern

Critical Pitfalls to Avoid

1. Don't delay treatment for "relative" contraindications - The 80.6% of patients excluded for late arrival represents the true tragedy 4. Time is brain.

2. Blood pressure management is crucial - Must achieve BP ≤185/110 mmHg BEFORE thrombolysis and maintain ≤180/105 mmHg for 24 hours after 8

3. Don't give aspirin within 24 hours of alteplase - Wait the full 24 hours unless compelling indication 8

4. Recognize that symptomatic ICH risk increases (OR 3.75,95% CI 3.11-4.51) but is outweighed by benefit in appropriate patients 3

5. The 2026 guidelines specifically modify the approach to contraindications - emphasizing individualized assessment over rigid exclusion 1

Thrombolytic Agent Selection

Alteplase (rt-PA) remains the gold standard with the most robust evidence 8, 5, 3. The 2026 guidelines discuss alternative thrombolytic choices, but alteplase has FDA approval for 0-3 hour window (3-4.5 hours off-label but guideline-supported) 1.

The European Stroke Organisation provides high-quality evidence supporting a more liberal approach to thrombolysis eligibility 5, which aligns with the 2026 AHA/ASA paradigm shift toward fewer absolute contraindications 1.