Intravenous Thrombolysis for Acute Ischemic Stroke – Evidence‑Based Criteria

Eligibility Requirements

• Blood pressure must be reduced to < 185/110 mm Hg before initiating alteplase in patients with acute ischemic stroke. 1
• Neuroimaging (CT or MRI) must exclude intracranial hemorrhage prior to alteplase administration. 1

Absolute Contraindications

Relative Contraindications & Special Populations

• Patients > 80 years old may receive alteplase within the 3‑hour window; data show no increase in symptomatic intracerebral hemorrhage. 3
• Patients with mild but potentially disabling deficits can benefit from alteplase despite low NIHSS scores. 3
• Seizure at stroke onset is not a contraindication if imaging confirms acute ischemia. 3
• Monotherapy with antiplatelet agents does not preclude alteplase. 1
• Combined antiplatelet therapy (e.g., aspirin + clopidogrel) allows alteplase, though the risk of symptomatic intracerebral hemorrhage may be higher. 1
• Cervical artery dissection: alteplase may be administered after careful risk‑benefit assessment. 3
• End‑stage renal disease on hemodialysis with normal aPTT: alteplase can be given. 1

All statements are derived from peer‑reviewed evidence cited above.

Stroke Thrombolysis Guidelines

Inclusion Criteria

• The American Heart Association recommends IV alteplase for patients with acute ischemic stroke presenting within 4.5 hours of symptom onset or last known well, if they meet eligibility criteria 4, 5
• Patients should have a clinical diagnosis of acute ischemic stroke causing measurable neurological deficit 4
• Symptom onset should be clearly defined and within 4.5 hours (or last known well time if onset unclear) 4, 6
• A CT or MRI scan should exclude intracranial hemorrhage 5, 6
• Age should be ≥18 years 4
• Blood pressure should be controlled to <185/110 mmHg before treatment initiation 6, 7

Exclusion Criteria

• The American Heart Association recommends excluding patients with active internal bleeding, history of intracranial hemorrhage, intracranial or intraspinal surgery within 3 months, serious head trauma within 3 months, or intracranial neoplasm, arteriovenous malformation, or aneurysm 4, 5
• Patients with current use of oral anticoagulants with INR >1.7, use of direct oral anticoagulants (DOACs) within 48 hours with elevated sensitive laboratory tests, or heparin use within 48 hours with elevated aPTT should be excluded 4, 5, 6
• Patients with platelet count <100,000/mm³ should be excluded 4, 5
• Blood pressure persistently >185/110 mmHg despite treatment is a contraindication 4, 6
• Blood glucose <50 mg/dL is a contraindication 5, 6
• CT or MRI showing multilobar infarction (hypodensity >1/3 cerebral hemisphere) is a contraindication 4, 5

Special Clinical Situations

• The American Heart Association recommends considering IV alteplase for patients with mild stroke symptoms (NIHSS <5) within 3-4.5 hours if symptoms are potentially disabling 4, 5
• Seizure at stroke onset may be treated with IV alteplase if evidence suggests residual deficits are from stroke, not postictal phenomenon 5, 6
• History of 1-10 cerebral microbleeds on prior MRI may be treated with IV alteplase 4, 5
• Diabetic hemorrhagic retinopathy or other hemorrhagic ophthalmic conditions may be treated with IV alteplase, weighing visual loss risk against stroke benefit 5
• Known sickle cell disease may be treated with IV alteplase 5
• Procedural stroke from cardiac or cerebral angiography may be treated with IV alteplase 5

Time Targets and Administration

• The American Heart Association recommends a door-to-needle time of <60 minutes in 90% of patients, with a median target of 30 minutes 6
• IV alteplase should be administered at a dose of 0.9 mg/kg body weight (maximum 90 mg total) 4, 6
• 10% of the dose should be given as an IV bolus over 1 minute, and the remaining 90% should be infused over 60 minutes 4, 6