Possible Contribution of the Aspiration Catheter in Preventing Post-stent Retriever Thrombectomy Subarachnoid Hemorrhage

Factors related to vessel displacement due to stent retriever retraction: An in vitro study

BACKGROUND

Thrombectomy with a stent retriever (SR) may lead to intracranial hemorrhage due to vessel displacement. We aimed to explore factors related to vessel displacement using an in vitro vessel model.

METHODS

A vessel model mimicking two-dimensional left internal carotid angiography findings was used in this study. Six SR types (Solitaire 3 × 40, 4 × 40, and 6 × 40; Embotrap 5 × 37; Trevo 4 × 41; and Tron 4 × 40) were fully deployed in the M2 ascending, M2 bend, or M1 horizontal portion. Subsequently, the SR was retracted, and the vessel displacement, maximum SR retraction force, and angle of the M2 bend portion were measured. A total of 180 SR retraction experiments were conducted using 6 SR types at 3 deployment positions with 10 repetitions each.

RESULTS

The mean maximum distance of vessel displacement for Embotrap Ⅲ 5 × 37 (6.4 ± 3.5 mm, n = 30) was significantly longer than that for the other five SR types (p = 0.029 for Solitaire 6 × 40 and p < 0.001 for the others, respectively). Vessel displacement was significantly longer in the M2 ascending portion group (5.4 ± 3.0 mm, n = 60) than in the M2 bend portion group (3.3 ± 1.6 mm, n = 60) (p < 0.001) and it was significantly longer in the M2 bend portion group than in the M1 horizontal portion group (1.1 ± 0.7 mm, n = 60) (p < 0.001). A positive correlation existed between the mean maximum SR retraction force or mean angle of the M2 bend portion due to SR retraction (i.e., vessel straightening) and the mean maximum distance of vessel displacement (r = 0.90, p < 0.001; r = 0.90, p < 0.001, respectively).

CONCLUSIONS

Vessel displacement varied with the SR type, size, and deployment position. Moreover, vessel displacement correlated with the SR retraction force or vessel straightening of the M2 bend portion.

Treatment practice of vasospasm during endovascular thrombectomy: an international survey

BACKGROUND AND AIM

The clinical importance and management of vasospasm as a complication during endovascular stroke treatment (EVT) has not been well studied. We sought to investigate current expert opinions in neurointervention and therapeutic strategies of iatrogenic vasospasm during EVT.

METHODS

We conducted an anonymous international online survey (4 April 2023 to 15 May 2023) addressing treatment standards of neurointerventionalists (NIs) practising EVT. Several illustrative cases of patients with vasospasm during EVT were shown. Two study groups were compared according to the NI's opinion regarding the potential influence of vasospasm on patient outcome after EVT using descriptive analysis.

RESULTS

In total, 534 NI from 56 countries responded, of whom 51.5% had performed >200 EVT. Vasospasm was considered a complication potentially influencing the patient's outcome by 52.6% (group 1) whereas 47.4% did not (group 2). Physicians in group 1 more often added vasodilators to their catheter flushes during EVT routinely (43.7% vs 33.9%, p=0.033) and more often treated severe large-vessel vasospasm with vasodilators (75.3% vs 55.9%; p<0.001), as well as extracranial vasospasm (61.4% vs 36.5%, p<0.001) and intracranial medium-vessel vasospasm (27.1% vs 11.2%, p<0.001), compared with group 2. In case of a large-vessel vasospasm and residual and amenable medium-vessel occlusion during EVT, the study groups showed different treatment strategies. Group 2 continued the EVT immediately more often, without initiating therapy to treat the vasospasm first (9.6% vs 21.1%, p<0.001).

CONCLUSION

There is disagreement among NIs about the clinical relevance of vasospasm during EVT and its management. There was a higher likelihood of use of preventive and active vasodilator treatment in the group that perceived vasospasm as a relevant complication as well as differing interventional strategies for continuing an EVT in the presence of a large-vessel vasospasm.