Stroke Thrombectomy

procedure

• Obtain access, often CFA with alternatives including radial and direct carotid access.

• If CFA access with tortuous iliacs, consider longer sheath

• Radial limited to 5-6 Fr sheath

• Direct carotid access, often short 6 Fr sheath. Should be closest to clavicle possible. Suture sheath in place and consider GA to avoid dislodgement. Can use Y-adaptor if plan for multiple exchanges.

• Select the ICA with 5 Fr catheter (e.g. Vert) and perform cerebral angiography in AP and lateral projections.

• Perform thrombectomy - many techniques with many variations

• Most techniques are slight variation on similar principles and tools, generally a large sheath or balloon guide catheter into the parent vessel (e.g. cervical ICA), aspiration catheter, microwire, microcatheter, +/- stent-retriever device

• Some advocate for trying aspiration alone first since faster and cheaper (ADAPT technique) with stent-retriever based techniques as back up

• If using stent-retriever, retrieval force directly related to degree of integration via proper positioning, pushing out closed cell stents, allow 5-7 minutes for integration

• Harder to retrieve with longer dwell time, multiple passes, and high fibrin content

• Higher risk of thrombus shearing with small aspiration catheter

• Distal to M2 and PCA can be challenging with ischemia risk from catheter being occlusive and shearing small perforators, particularly distal superior MCA branches along frontal operculum

• ADAPT FAST technique

• Place balloon guide catheter or large sheath into parent vessel

• Advance triaxial system but AVOID distal passage

• Remove microwire and microcatheter

• Slight negative pressure on aspiration catheter with 50 mL syringe until absence of backflow

• Inflate BGC if using, advance aspiration catheter slight forward and then slowly withdraw under forceful negative aspiration

• E.g. default Einstein approach: 8F groin sheath, 4F Berenstein cath and glidewire advantage, Neuro Max sheath, Penumbra 68, Penumbra 3 max, Marksman cath, fathom 0.016 vs synchro 2 0.014

• Balloon Guide/ Stent-retriever

• Advance balloon guide catheter (e.g., Cello, Merci, or FlowGate 2)

• Attached RHV with side port, flush catheter, and prep balloon

• Good to use 1 cc syringe for inflation with 50/50 contrast to not over inflate and damage the vessel

• Attach two 60 mL syringes for negative aspiration

• Advance microwire (e.g. synchro 2) and microcatheter (e.g. velocity) beyond clot with gentle puff to confirm

• Advance and unsheath stent-retriever device andallow to integrate in clot 5-7 min

• Retriever device and microcatheter as a unit into the guiding catheter under constant aspiration until good flow reversal

• *DO NOT perform >3xs in same vessel*

• Solumbra technique

• Advance large sheath into cervical internal carotid

• Neuron Max may be superior in terms of distal softness and proximal support vs Cook Shuttle, Terumo Destination, Stryker AXS)

• Advance distal aspiration catheter, microcatheter, and microwire to clot as above and deploy stent-retriever

• Advance aspiration catheter under suction to clot until drip rates slows in tubing

• Remove stent-retriever and aspiration catheter as single unit into cervical sheath

• CAPTIVE technique

• Advance large sheath into cervical ICA followed by triaxial system as above

• Advance stent-retriever but turn on aspiration catheter prior to deployment

• Remove microcatheter and advance aspiration catheter until drip rate slows in tubing (holding clot “captive”)

• Remove stent-retriever and aspiration catheter as single unit into cervical sheath

• TRAP/ARTS technique

• Advance balloon guide catheter into ICA

• Advance triaxial system to clot as above and deploy stent-retriever using forward tension technique

• Remove microcatheter and inflate balloon guide catheter balloon

• Initiate aspiration catheter during withdrawal of retriever until there’s resistance on the retriever wire suggesting the clot is “trapped”

• Remove stent-retriever and aspiration catheter as single unit while aspirating through the balloon guide catheter

• SAVE technique

• Deploy ⅔ of stent-retriever distal to clot using the active push deployment technique

• Advance aspiration catheter to edge of clot and starting aspiration until wedged

• Switch aspiration to guide catheter while maintaining vacuum on aspiration catheter with  a syringe

• Remove stent-retriever and aspiration catheter as single unit while aspirating through the guide catheter

• GUARD technique

• Advance 6 Fr flexible large bore guide sheath (e.g. Neuro Max) into distal petrocavernous ICA

• Adjunctive DAC aspiration and stent-retriever similar to above

• Can give IA rt-PA <10 mg for distal fragments even after IV rt-PA. IA GPIIb/IIIa inhibitors may also be safe in a small series.

• Refractory cases (8.7% US cohort, 14.6% Korean cohort), e.g., intracranial dissection, refractory clot, or underlying significant atherosclerotic stenosis

• IA GPIIb/IIIa inhibitor or primary stenting likely ideal, no difference in treatment failure (NW experience)

• Angioplasty alone tended to have worse outcomes and lead to stenting anyways

• Completion angiography to assess thrombolysis in cerebral infarction (TICI) scale

• Grade 0 (no perfusion), 1 (minimal perfusion), 2A (<2/3 filling of vascular territory), 2B (complete filling but delayed), 3 (complete perfusion)

• +/- Adjunctive carotid artery stenting or PFO closure

• PFO/ASD closure recommended for ASD or 2nd cryptogenic stroke with PFO, otherwise debated, mixed results w/ RTCs (CLOSURE 1, PC, RESPECT trials). Guidelines generally recommend medical management.

• Obtain hemostasis (can use closure devices for carotid access)