Abstract Body: Introduction: Randomized clinical trials evaluating the effects of endovascular treatment (EVT) for medium vessel occlusion (MeVO) are ongoing. However, it remains unclear how clinicians determine the indication for EVT in MeVO cases in real-world practice
Hypothesis: We hypothesize that in actual clinical practice, there is a threshold of clinical symptoms and perfusion imaging findings that guide the decision to intervene with EVT for MeVO.
Methods: We conducted a single-center retrospective registry from April 2019 to April 2024, enrolling consecutive patients with acute ischemic stroke due to MeVO. We compared the outcomes of MeVO patients who received EVT with those who received medical treatment (MT). The primary outcome was defined as a good functional outcome, indicated by a modified Rankin scale score of 0-2 at 90 days post-stroke onset. Secondary outcomes included exploring the optimal thresholds for EVT intervention in real-world clinical practice, based on clinical symptoms indicated by the National Institutes of Health Stroke Scale and perfusion imaging using RAPID software.
Results: We analyzed 162 patients (EVT, n = 102; MT, n = 60). The mean age was 80 years, with 53.7% being men. Recombinant tissue plasminogen activator was used more frequently in the EVT group (42.2% vs. 18.3%). The median NIHSS was higher in the EVT group (median [interquartile range, IQR]; 13 [6–19] vs. 7 [2–14]). In terms of perfusion imaging, there was no significant difference between the two groups in CBF < 30% (median [IQR]; 4 [0–17] vs. 4 [0–22]). However, the median T max > 6 sec and mismatch volume were significantly higher in the EVT group (median [IQR]; 44 [27–82] vs. 28 [6–49] and 35 [21–55] vs. 12 [2–28], respectively). The primary outcome was not significantly different between the EVT and MT groups (41 [40.2%] vs. 25 [41.7%]; adjusted odds ratio [aOR]: 1.10 [95% CI: 0.42–2.89]). Receiver-operating characteristic analyses showed that the areas under the curves for NIHSS, CBF < 30%, T max > 6 sec, and mismatch volume were 0.64, 0.49, 0.68, and 0.74, respectively. Mismatch volume had the best discriminatory power with respect to EVT intervention, with a threshold of 20 ml.
Conclusions: A mismatch volume of ≥ 20 ml may be a useful criterion for determining EVT intervention in MeVO cases in real-world practice.