Premio nazionale per la ricerca sull'ictus cerebrale "HIPPONION – ISA-AII"

Background: Futile recanalization (FR) is defined as poor 90 outcome or lack of neurological improvement at 24 hours despite successful recanalization in AIS with LVO treated by mechanical throbectomy (MT). No-reflow phenomenon (NRP) could be a possible cause of FR but its evidence in AIS patients is scarce. Methods: We retrospectively analyzed 185 digital subtraction angiographies (DSA) of AIS patients with anterior circulation LVO after endovascular treatment (EVT). In order to better define NRP, we designed a score called modified capillary index score (mCIS). The score is obtained by dividing middle cerebral artery territory in three segments. For each segment we gave 2 points if the capillary blush was present without any delay, 1 if delayed and 0 if absent. The primary endpoint 2 was to use mCIS to identify NRP on post-interventional DSA and to test whether this marker may predict FR and fENI. Secondary endpoint was to search a correlation between NRP, lesion volume and hemorrhagic transformation. We used ROC curve to define mCIS≤3 as cut-off and marker of NRP. Results: NRP was present in 35.1% of patients. NRP predicted fENI at 24h (aOR 2.825, 95%CI 1.265–6.308, P=0.011) and at 7 days (aOR 2.191, 95%CI 1,008-4.762, P=0.048), but not 90-day FR. Moreover, NRP predicted hemorrhagic transformation (aOR2.444, 95%CI 1.266–4.717, P=0.008). Conclusions: Modified capillary index score (mCIS) seems useful in identifying NRP in AIS patients. In addition, mCIS was able to predict NRP that correlated with early clinical outcome and hemorrhagic transformation of the ischemic lesion. An external validation of the score is warranted.