Thesis title: "No-reflow phenomenon" in patients with acute ischemic stroke from large vessels occlusion treated successfully with mechanical thrombectomy: an angiographic evaluation.
Introduction:
In acute ischemic stroke (AIS) FR is defined as poor 90-days outcome or lack of neurological improvement at 24 hours or at 7-days despite successful recanalization in patients receiving MT for LVO. NRP could be a possible cause of FR but its evidence in AIS patients is scarce. Aim of this research was to identify NRP with a possible angiographic marker, through a retrospective analysis of post MT DSA to define brain capillary status after successful recanalization. From imaging analysis, we created a post-interventional angiographic score: the modified Capillary Index Score (mCIS).
Methods:
We retrospectively analyzed 190 DSA of AIS patients with anterior circulation LVO after MT. In order to better define NRP, we designed a score named 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 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:
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.