Abstract 1122‐000009: Impact of RNF213 p.R4810K Variant on Endovascular Therapy Outcome for Acute Large Vessel Occlusion Stroke
Authors: Yoshimoto Takeshi , Yoshimoto Takeshi , Tanaka Kanta , Koge Junpei , Saito Satoshi , Yamagami Hiroshi , Nakaoku Yuriko , Nishimura Kunihiro , Yamaguchi Eriko , Chiba Tetsuya , Kawakami Daisuke , Shiozawa Masayuki , Kamogawa Naruhiko , Ohta Tsuyoshi , Satow Tetsu , Inoue Manabu , Hattori Yorito , Washida Kazuo , Kataoka Hiroharu , Toyoda Kazunori , Koga Masatoshi , Ihara Masafumi 
Published: December 2021

Introduction
: The ring finger protein 213 gene (
RNF213
) has been identified as a susceptibility gene for moyamoya disease, and the p.R4810K polymorphism as a founder variant commonly found in East Asian patients.

1

 A recent large case‐control study including over 46,958 Japanese subjects reported that the 
RNF213
 p.R4810K variant was a strong risk factor for Japanese cerebral infarction: the variant was found in 5.2% of patients with non‐cardioembolic stroke and in 2.1% of healthy controls.

2  

Mechanical thrombectomy (MT) is a standard treatment for acute ischemic stroke due to occlusion of the internal carotid artery and M1 segment of the middle cerebral artery, but in East Asians, about 15–25% of LVOs for which MT was performed were reportedly caused by intracranial atherosclerotic disease (ICAD).

3

 
RNF213
 p.R4810K variant may be involved to some extent in ICAD‐related LVO of Asian patients undergoing MT. In this study, we aimed to investigate the impact of 
RNF213
 p.R4810K variant on EVT for anterior circulation LVO stroke.

Methods
: Of the consecutive ischemic stroke patients from 2011 to 2021 seen in our institute, patients who underwent EVT for acute occlusion of the intracranial ICA or M1 segment of MCA and signed a consent form for 
RNF213
 genotyping were included. Outcomes were instant re‐occlusion, final modified Thrombolysis in Cerebral Infarction (mTICI) ≥2b reperfusion, early re‐occlusion, and modified Rankin Scale (mRS) score 0–2 at 90 days. Instant re‐occlusion was defined as occurrence of re‐occlusion during the procedure, whereas early re‐occlusion as re‐occlusion detected on magnetic resonance angiography within 2 weeks after confirmation of successful reperfusion at the end of the procedure.

4

Results
: Of the 277 patients (128 women [46.2%]; median age, 76 years) analyzed, 10 (3.6%) patients had the 
RNF213
 p.R4810K variant. The variant carriers were younger (67 years vs. 76 years, 
P
<0.01), more frequently received angioplasty (40.0% vs. 12.0%, 
P
<0.01), and more frequently had intracranial atherosclerotic disease‐related LVO as a cause of acute LVO (70.0% vs. 8.6%, 
P
<0.01) than non‐carriers. The variant carriers showed higher rates of instant re‐occlusion (40.0% vs. 5.6%, 
P
<0.01), but there were no statistically significant inter‐group differences for the final mTICI ≥2b reperfusion rate between carriers and non‐carriers (100.0% vs. 81.6%, 
P
= 0.22). Early re‐occlusion was more frequent in the variant carriers than non‐ carriers (60.0% vs. 0.4%, P<0.01) with no intergroup difference in the rate of repeated EVT (67.7% vs. 100.0%, P = 0.71). There were no statistically significant inter‐group differences for achievement of mRS score 0–2 (60.0% vs. 51.7%, 
P
= 0.75)

Conclusions
: Both instant and early re‐occlusion were more frequent in the 
RNF213
 p.R4810K variant carriers who had received EVT for acute anterior circulation LVO than in the non‐carriers. Potential impact of 
RNF213
 polymorphism status on EVT outcomes was clarified.