LINNC Americas - Daily report Day
The first LINNC course of the year is taking place – as usual – in sunny Miami! And, as usual, it covers the entire spectrum of INR, leading to very interesting and informative discussions!
STROKE and ICAD
After the opening ceremony, the day began with Dr Victor Torres from Columbia presenting the first selected case from those submitted by the attendees – a very interesting stroke case of an atypical “tandem” occlusion of the brachiocephalic trunk and right MCA. Having failed to recanalize le brachiocephalic trunk coming from the femoral route, his team chose to do the recanalization from a second, right radial access, inspired by the “rendez-vous” technique currently used in peripheral interventional radiology. This enabled access to the ICA from the femorally inserted guiding catheter and allowed the for an MCA revascularization. The brachiocephalic trunk then underwent angioplasty and stenting.
Continuing with the topic of ischemic disease, Prof. Laurent Spelle presented two recorded stroke treatment cases. The first concerned a posterior fossa stroke in a patient with acute Covid having a basilar artery occlusion with a floating clot inside the aortic arch obliterating the left subclavian artery. The recanalization was performed by distal aspiration through a right radial artery access in order to avoid mobilizing the aortic thrombus, which gave Prof. Spelle the occasion to review the literature about stroke during Covid infections.
The second recorded stroke case was of a patient who had an acute tandem ICA and MCA occlusion on the right side while having a chronic occlusion of the left ICA. Despite an excellent recanalization result performed using a stent retriever thrombectomy with distal aspiration (the ADAPT technique), the patient had a severe negative clinical presentation and the evolution was unfavorable.
Then Dr Jane Khalife from the USA presented a case of a symptomatic tight stenosis of the left pericallosal artery and discussed the different treatment strategies. Since the balloon mounted stent did not navigate to the target artery, in the end, the stenosis was treated by balloon angioplasty and subsequent stenting with a laser-cut stent. During the discussion that followed, Prof. Vitor Mendes Pereira hypothesized that the present stenosis was due to chronic trauma since it was localized at a spot facing the falx cerebri and might have resulted from a dissection, thus behaving differently than a “classic” ICAD.
AVM and AVF
The second subject of the day was AVM and we began with Prof. Jacques Moret showing a recorded case of a straightforward intra-arterial embolization of an occipital AVM remnant. The AVM had previously bled and been partially embolized during the acute phase. Prof. Moret explained that, when using liquid emboli, he always favors the microcatheter with the longest detachable segment possible in order to be able to build a solid plug. The case gave rise to an interesting and lively discussion about the management of AVMs, the timing to treat after rupture, and how long we should follow up a completely cured AVM patient.
The basic question, nevertheless, remains the indications for AVM treatment, regardless of the strategy, since the randomized ARUBA trial demonstrated that any treatment is worse than the natural history of the disease, and the preliminary results of TOBAS seem to point in the same direction. In this context, Prof. Tudor Jovin advocated for a new ARUBA-like study, explaining that with the evolving technology that we have today, he feels the natural history of AVMs might not be seen as that favorable. However, Prof. Moret pointed out that even with safer treatments, we should remain humble since we face biological reactions in treated AVMs that we neither understand nor control and which can lead to delayed bleeding in spite of a complete occlusion.
Concerning the topic of AVF, Dr Nathaniel Ellens from the USA presented a case of a dural AFV occurring after stenting of a venous sinus to treat idiopathic hypertension. The fistula was managed by embolization via the middle meningeal artery with so-called venous remodeling. He discussed the hypothesis that the fistula might be a consequence of parietal inflammation of the venous sinus related to a small clot trapped between the stent and the vessel wall.
The submitted case by Dr Pierre-Olivier Comby from Montréal, Canada dealt with an exceptional case of a spinal epidural arterio-venous fistula with intradural drainage through the left radicular L3 vein which explained the patient’s symptoms. Since arterial access was difficult and the primary goal of the treatment was to disconnect this drainage, the treatment was performed from the venous side.
The next topic of the day was the treatment of aneurysms. Prof. Vitor Mendes Pereira, in his first meeting as a LINNC Course Co-Director, presented a case recorded at St Michaels Hospital in Toronto, Canada of a recurrent PCom aneurysm which he treated with a flow diverter. Using this case Prof. Mendes Pereira highlighted the tremendous contribution that OCT imaging can have in INR, demonstrating the use of a high frequency OCT probe dedicated for neuro-intervention going through a 0.21’ microcatheter. This tool, which has an incredible spatial resolution of up to 10 µ, is equally useful for diagnosis and monitoring during procedures with stent placement since it can precisely show the sections with poor parietal apposition of the stent and guide balloon angioplasty. Moreover, there are no artifacts due to the presence of coils from anterior treatments, the contrary of CBCT.
Dr Ricardo Hanel presented another technical innovation, a new torqueable and shape-retaining micro-guidewire – the Aristotle. Its particular feature is that it is available in different diameters – 14, 18 and 24 – since the choice of a larger wire reduces the ledge effect during navigation of the microcatheter and may avoid going into perforators. Dr Hanel illustrated the use of these microwires with a case of a giant carotid syphon aneurysm treated by flow diverters.
Prof. Laurent Spelle presented three recorded cases of very difficult aneurysm treatments. The first case involved a giant dissecting fusiform basilar artery aneurysm with partial thrombosis and was treated using a staged management. Prior to the endovascular treatment itself the patient underwent posterior fossa craniectomy in order to manage the oedema due to the anticipated modifications in the thrombus as well as to prevent brain stem compression. The interventional treatment was accomplished under double antiplatelet treatment and involved four steps: 1st, a balloon occlusion test showed the impossibility of occluding the basilar artery in this specific patient; 2nd, scaffolding was accomplished of the basilar artery until the dominant left vertebral artery by a long braided stent; 3rd, flow diverters were placed inside the braided stent and; 4th, coil embolization of the aneurysm was used in order to decrease the amount of clot inside the sac and occlude the hypoplastic right vertebral artery. The take-home message of this case was that pre-interventional craniectomy can save a patient’s life.
The second recorded aneurysm case was a ruptured blood-blister-like basilar artery aneurysm treated by a variant of stent-jacking with a flow diverter and deployment of a coil inside the pouch.
The third case was a recurrent, previously ruptured, ACom aneurysm, treated with a laser-cut stent which was deployed from the right A2 to the contralateral A1 with subsequent coiling.
Finally, two industry sponsored symposiums completed the overview of the aneurysm topic.
First Prof. Spelle presented the results of the CLEVER study during the Microvention symposium. This study evaluated the safety and efficacy of the latest generation of the WEB device, the WEB 17, finding it to be equivalent to previous generations of this device.
Then Dr Robert Fahed from Ottawa, Canada presented his experience with the Surpass Evolve flow-diverter stent during the Stryker symposium.
THE DARK SIDE OF INR
The last topic of the day was not the least: complications!
Faculty members and attendees presented some of their complications along with – importantly – the lessons learned from their mistakes.
Prof. Spelle presented a recorded case of an intraparenchymal hematoma. This occurred after the flow-diverter treatment of two MCA bifurcation aneurysms during which a perforation of a distal branch by a microguide had occurred. This perforation was not noticed by the operator and Tirofiban was given to prevent thrombosis of the covered bifurcation branches. The mistake here was that no CBCT had been performed prior to the administration of the anti GP-IIb/IIIa.
Another complication of the pressure-cooker technique was presented by Dr Francisco Mont’Averde from Foertaleza, Brazil concerning an untargeted embolization due to the undetectable reflux of insufficiently homogenized EVOH. Finally, Dr Mont’Averde was able to manage this complication by performing an embolectomy with a stent retriever.
Then Prof. Moret showed a recorded case of a transarterial embolization of a cerebellar AVM using the pressure-cooker technique with a detachable tip microcatheter advanced via the ipsilateral vertebral artery and a microcatheter for the glue advanced via the opposite one. The treatment was complicated by a hemispheric cerebellar and spinal ischemia which led to a significant handicap for the patient, due to an important and uncontrolled reflux of glue in the PICA. Prof. Moret explained that placing two microcatheters in a small artery raises the risk of faster and longer reflux which is, moreover, difficult to see.
During the other presentations, Dr Dana Iancu from Montreal, Canada showed us a case of a spinal infarct after a complicated attempt at treating a basilar tip aneurysm with Y stenting that had to be recaptured because of acute per-procedure thromboses.
Dr Jose De Jesus Gutierrez-Banos from Mexico presented the case of a ruptured PCom aneurysm treatment with a succession of thrombotic and hemorrhagic complications which finally resulted in a large hemispheric stroke.
And Dr Yeison Esteban Montana Munoz presented the case of middle meningeal artery lesion by a transcutaneous inserted canula into the foramen ovale for the treatment trigeminal neuralgia.
After this difficult and challenging session, the day was crowned by a cocktail at the poolside of the hotel.
And now it’s time to get ready for what Day 2 promises at LINNC Americas!
Report by Dr Sophie GALLAS & Dr Léon IKKA