Management of difficult thrombectomy resulting in unproductive passes due to:
Highlights*: the newest devices on the market: Clotild and Thromb X
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Failed thrombectomy reasons:
MID-BA ICAD MANAGEMENT step-by-step:
It is important to prove the ICAD à run from ipsilateral ICA to reveal the presence of PCoM and patency of the top of BA and PCAs
- sheath at the origin of VA
- run from the VA
- gentle aspiration at the level of the ICAD from aspiration catheter to clean up the lesion because there will be always some clot on the ruptured atherosclerotic plaque
- once the lesion is cleaned and ICAD confirmed, the stenosis can be passed by microcatheter and SR can be introduced and opened at the level of stenosis
- Dyna-CT to exclude the hemorrhage
- if there is no bleeding – introduction of antiplatelet therapy (Integrilin iv.)
- coronary balloon angioplasty of the lesion
Special remarks:
*pay attention to washout from the competitive flow – do not confuse it with occlusion
- characteristic run pattern: up and down
*do the run after 1st pass very quickly otherwise the lesion may reocclude and you will not see the point of the stenosis
*do not finish the procedure immediately after successful recanalization, do delayed runs of stenosis because it can occlude with a delay
First-line contact aspiration vs. stent-retriever in ICAD according to publication and Slice Faculty:
Antiplatelet therapy in ICAD:
Highlight*:
2 . REFRACTORY CLOTS:
A) WHITE THROMBI:
PINCHING TECHNIQUE step by step
- pass with wire and microcatheter between the thrombus and the vessel wall
- introduce the Nimbus device, position it properly (tip to tip with microcatheter, the dense marker few millimeters behind the front of the thrombus) and unsheathe it
- push the microcatheter while slightly pulling back the Nimbus until you feel resistance = pinning the clot (you can use torque device to better control the wire of the stent and block it after pinning to keep the tension on the stent)
- retrieve en bloc: intermediate catheter-microcatheter-SR while maintaining the tension on microcatheter, aspirate from the BCG and/or aspiration catheter
*if the clot is trapped in BCG – keep negative pressure on the balloon, deflate it and remove it (long sheath can be beneficial in these cases)
Highlight*:
B) BIFURCATION THROMBI:
Double stent-retriever technique - applications:
- T occlusion
- flip flopping bifurcation MCA clot
- sticky rolling thrombus
- second line treatment in other types of clots
DOUBLE STENT-RETRIEVER TECHNIQUE step by step:
- deploy the first SR (MCA) via microcatheter and remove the microcatheter
- place the same microcatheter in second occluded branch (ACA) and deploy the second SR
or
- go through BCG: deploy the first SR and partially recapture it with microcatheter so you could easily pass to the second branch with another device
- place the second SR in the second occluded branch
- remove both microcatheters
- do a blind exchange using an aspiration catheter*
*double stent technique may generate lot of frictions – to improve the safety you can use an intracranial catheter and/or reduce the length of opened stents
- possible combination of stents:
INITIAL/RESCUE STENTING step by step
- if you are sure that it is calcified emboli, you can go directly with stenting
- if you are not sure, try first attempt as usually in MT with either aspiration or SR (sometimes calcification is combined with thrombus)
- it can be difficult to even cross the lesion with a microcatheter and a wire
- 20 min before stent-implantation, give GP IIb/IIIa inhibitor to the patient (you should never combine it with heparin because of high risk of hemorrhage)
- depending on the size of calcification, the concomitant thrombus and their location, you can use self-expanding stents or balloon-mounted stents
- stent types in use (mandatory: high radial force and/or oversizing): Wingspan, Enterprise, Atlas, Credo, Solitaire AB, balloon-mounted stents (with caution because of higher risk of rupture)
Rescue stenting for failed mechanical thrombectomy (in publication):