Bringing forward reperfusion with oxygenated blood perfusion beyond arterial occlusion during endovascular procedures in patients with acute ischemic stroke.
BACKGROUND AND PURPOSE
High recanalization rates achieved with endovascular procedures are not always followed by the expected clinical improvement. These time-consuming procedures imply a delayed reperfusion despite the capacity of earlier intravascular microcatheter bypass to the ischemic tissue beyond the clot. We aimed to explore the safety and feasibility of MOB beyond the clot.


MATERIALS AND METHODS
We studied patients with stroke undergoing endovascular procedures. The timing of procedural steps was recorded. We then explored the safety and feasibility of repeated femoral artery MOB injections beyond the occlusion every time the clot was crossed in 17 patients. Pre- and postocclusion flow was continuously monitored with TCD.


RESULTS
We studied 60 patients (mean age, 70 ± 11 years; median NIHSS score, 20; IR, 18-21). Of them, 33 (55%) received IV-tPA before the endovascular procedure. The following arteries were occluded: the MCA (63.3%, n = 38) and the ICA (36.6%, n = 22). The TSO to arterial puncture was 193 ± 77 minutes. The occluding clot was successfully crossed with the microcatheter in 46 patients (76.6%; mean TSO, 228 ± 82 minutes). Recanalization was achieved in 44 patients (73.2%; mean TSO, 328 ± 144 minutes). Repeated MOB injections were performed in 17 patients. Patients with/without MOB presented with similar baseline characteristics. The median number of MOB injections was 2 (IR, 2-3), and the median injected blood volume was 40 mL (IR, 27.5-50). The mean time from first MOB to arterial recanalization was 136 ± 86 minutes. During MOB, a nonpulsatile flow appeared in previously nonvisible distal branches on TCD.


CONCLUSIONS
In this small series, oxygenated blood delivered through a microcatheter positioned distal to the site of occlusion was feasible and safe. Until final recanalization is achieved, MOB injections may generate intermittent reperfusion for up to 2 hours.