Internal Carotid Artery Reconstruction with a "Mega Flow Diverter": First Experience with the 6×50 mm DERIVO Embolization Device

Triple therapy versus dual-antiplatelet therapy for dolichoectatic vertebrobasilar fusiform aneurysms treated with flow diverters

Background

Dolichoectatic vertebrobasilar fusiform aneurysms (DVBFAs) have poor natural history when left untreated and high morbimortality when treated with microsurgery. Flow diversion (FD) with dual-antiplatelet therapy (DAPT) is feasible but carries high risk of perforator occlusion and progression of brainstem compression. Elaborate antithrombotic strategies are needed to preserve perforator patency while vessel remodeling occurs. We compared triple therapy (TT (DAPT plus oral anticoagulation)) and DAPT alone in patients with DVBFAs treated with FD.

Methods

Retrospective comparison of DAPT and TT in patients with DVBFAs treated with FD at eight US centers.

Results

The groups (DAPT=13, TT=14) were similar in age, sex, clinical presentation, baseline disability, and aneurysm characteristics. Radial access use was significantly higher in the TT group (71.4% vs 15.3%; P=0.006). Median number of flow diverters and adjunctive coiling use were non-different between groups. Acute ischemic stroke rate during the oral anticoagulation period was lower in the TT group than the DAPT group (7.1% vs 30.8%; P=0.167). Modified Rankin Scale score decline was significantly lower in the TT group (7.1% vs 69.2%; P=0.001). Overall rates of hemorrhagic complications (TT, 28.6% vs DAPT, 7.7%; P=0.162) and complete occlusion (TT, 25% vs DAPT, 54.4%; P=0.213) were non-different between the groups. Rate of moderate-to-severe disability at last follow-up was significantly lower in the TT group (21.4% vs 76.9%; P=0.007).

Conclusions

Patients with DVBFAs treated with FD in the TT group had fewer ischemic strokes, less symptom progression, and overall better outcomes at last follow-up than similar patients in the DAPT group.

Implantation of Large Diameter (5.5-6 mm) Derivo Embolization Devices for the Treatment of Cerebral Aneurysms

BACKGROUND

The efficacy of flow diverters is dependent upon robust wall apposition in the parent artery. Usage in large caliber cerebral vessels has therefore been limited as few implants with diameters > 5 mm exist. We present our initial experience in treating cerebral aneurysms using the 5.5 mm and 6 mm diameter implants of the Derivo embolization device (DED).

METHODS

Our prospectively maintained institutional database was reviewed to identify patients in whom a > 5 mm DED was implanted between November 2016 and February 2021. The primary efficacy outcome was complete or near-complete aneurysm occlusion at 6 months (O'Kelly-Marotta, OKM, C-D, adapted for magnetic resonance angiography). Safety outcomes included 30-day major morbidity defined as modified Rankin Score (mRS) 3-5, mortality, serious adverse events and procedural complications.

RESULTS

A total of 21 large diameter DEDs were deployed in 18 patients (age 59.5 ± 14.1 years), harboring 19 unruptured aneurysms. Of the aneurysms 14 (73.7%) were saccular in morphology (sac diameter 10.9 ± 5.5 mm, neck diameter 6.8 ± 3.1 mm), 3 (15.8%) aneurysms were dissecting, 1 (5.3%) iatrogenic pseudoaneurysm and 1 (5.3%) fusiform. Aneurysm locations were: ICA (internal carotid artery) (n = 17); (7 cavernous, 4 paraophthalmic, 2 paraclinoid, 1 petrous, 2 communicating, 1 cervical); vertebrobasilar (n = 2). Adjunct stenting to optimize proximal wall apposition was undertaken in 5 (27.8%) patients. At 6 months 75% of patients followed-up met the primary efficacy endpoint (OKM C-D). There were no serious adverse events, 30-day major morbidity (mRS 3-5) or mortality.

CONCLUSION

Implantation of large diameter (5.5 mm and 6 mm) DEDs into capacious cerebral vessels to treat a range of complex aneurysms is safe and technically feasible but may require adjunct stenting to optimize proximal wall apposition. Short-term efficacy of this device subset is comparable to previous DED and other flow diverter studies. Long-term follow-up and comparative studies are required for further assessment.

Outcome of intracranial flow diversion according to the antiplatelet regimen used: a systematic review and meta-analysis

Background

Thromboembolic complications are not uncommon in patients undergoing neurointerventional procedures. The use of flow diverting stents is associated with higher risks of these complications despite current dual antiplatelet regimens.

Objective

To explore contemporary evidence on the safety of emerging dual antiplatelet regimens in flow diverting stenting procedures.

Methods

We performed a systematic review and meta-analysis to identify relevant articles in electronic databases, and relevant references. Studies reporting the complications and mortality of flow diverting stenting procedures using acetyl salicylic acid (ASA) + ticagrelor or ASA + prasugrel compared with ASA + clopidogrel were included.

Results

Of 452 potentially relevant studies, we identified 49 studies (2526 patients) which reported the safety of ticagrelor or prasugrel for pooled analysis, and five studies (1005 patients) for meta-analysis. The pooled overall mortality in all studies was 2.14%, ischemic complications 6.89%, and hemorrhagic complications 3.68%. The use of ticagrelor or prasugrel was associated with a lower risk of mortality compared with clopidogrel (RR=4.57, 95% CI 1.23 to 16.99; p=0.02). Considering ischemic events, ASA + clopidogrel was as safe as ASA + prasugrel (RR=0.55, 95% CI 0.11 to 2.74; p=0.47) and ASA + ticagrelor (RR=0.74, 95% CI 0.32 to 1.74; p=0.49). ASA +ticagrelor was not associated with a higher risk of hemorrhagic complications (RR=0.92, 95% CI 0.27 to 3.16; p=0.89).

Conclusions

Evidence suggests that dual antiplatelet regimens including ticagrelor or prasugrel are safe for patients undergoing flow diversion procedures. Regimens using ticagrelor were associated with better survival than those using clopidogrel in the included studies.