The purpose of this study is to determine whether super-selective intra-arterial administration of verapamil immediately following successful intra-arterial thrombolysis is safe as a potential neuroprotective agent. Standard procedures are cerebral angiography and intra-arterial thrombolysis (intra-arterial administration of tPA and/or mechanical thrombectomy). Experimental procedure is superselective injection of verapamil intra-arterially.