Intra-arterial thrombolysis

Created 16/09/2022, last revision 06/11/2023

  • intra-arterial thrombolysis (IAT) = administration of thrombolytic agent via catheter directly into the occluded artery
  • several trials using prourokinase (MELT, PROACT) and alteplase ( IMS-3, SYNTHESIS) showed the benefit of this therapy
    • MELT  The Middle Cerebral Artery Embolism Local Fibrinolytic Intervention Trial) 
    • PROACT-2  (Prolyse in Acute Cerebral Thromboembolism)
    • IMS 3 (Interventional Management of Stroke trial)
      • demonstrated that the combined IV+IA approach to recanalization may be more effective than standard IVT alone for moderate to severe strokes with a similar safety profile
  • alteplase (tPA) is used in clinical practice; dosage is not standardized
  • the standard therapeutic window for IAT was 0-6h; studies with advanced imaging (showing penumbra) are not available (the individual window can theoretically be taken from IVT studies – but this is not discussed in the guidelines)


  • indications are the same as for mechanical thrombectomy (MT)
  • IAT is nowadays rarely used as a stand-alone procedure; MT is preferred as a more potent recanalization technique
  • IAT can be performed:
    • when the thrombus is inaccessible for mechanical recanalization (extreme kinking, etc.)
    • to treat distal embolization (incl. those occurring during embolectomy)  (Khatri, 2022)  [Kaesmacher, 2019]
    • as a rescue procedure after failed MT; the good effect of MT followed by IAT was reported in the CHOICE trial  (Zaidi,2019)


Apart from the usual contraindications to thrombolysis :

  • arterial dissection
  • proximal (usually carotid) stenosis or significant coiling preventing a microcatheter delivery to the occluded segment
  • extensive signs of ischemia on CT or absence of penumbra on CT perfusion


Dosing according to original IAT protocols

Content available only for logged-in subscribers (registration will be available soon)

IAT after previous mechanical thrombectomy

  • tPA dosing according to the CHOICE trial – alteplase 0.225 mg/kg; max 22.5 mg, administered within 15-30 minutes in patients with TICI 2b-3
Successful intra-arterial thrombolysis of occluded basilar artery

Related Content

You cannot copy content of this page

Send this to a friend
you may find this topic useful:

Intra-arterial thrombolysis