Abstract 157: A Streamlined Hyperacute MRI Protocol Identifies IV tPA-Eligible Stroke Patients When Initial Clinical Assessment Favors Stroke Mimic
Background: The possibility of a stroke mimic (SM) challenges the initial clinical assessment of patients presenting with suspected acute ischemic stroke (AIS). When SM is deemed likely, IV tPA may be withheld, risking an opportunity to treat an AIS. Though not routinely used in the hyperacute setting, MRI may help in diagnosing stroke when SM is favored but not certain. We hypothesized that a streamlined, hyperacute MRI (HMRI) protocol would identify a small, but important, group of IV tPA-eligible AIS patients among those initially favored to have SM.
Methods: A streamlined HMRI protocol was designed based on several identified barriers to rapid patient transport, MR image acquisition, and post-MRI tPA delivery. Treating neurologists were trained to only order HMRI when SM was favored and IV tPA was being withheld (Fig). Use of HMRI for tPA decision-making, as well as baseline variables, door-to-needle times (DNT), and discharge outcomes were compared before HMRI implementation (“Pre-HMRI”: 8/1/2011-7/31/2013) and after (“Post-HMRI”: 8/1/13-7/31/14).
Results: Post-HMRI, 53 patients with suspected SM, who were otherwise IV tPA eligible, underwent HMRI (median MRI order to start time 29 min). Seven of 53 patients (13%) were subsequently diagnosed with AIS based on HMRI, of whom 4 received IV tPA; 3 were excluded from IV tPA due to blood pressure, symptom improvement, and change in last known normal time. Pre-HMRI, 158 patients were treated with IV tPA, of whom none received IV tPA aided by HMRI. Post-HMRI, 80 patients were treated with IV tPA, of whom 4 patients (5%) were treated with IV tPA utilizing HMRI results (0 vs 5%, p=0.012). In pre- and post-HMRI IV tPA-treated patients, DNT (39 vs 37 min, p=0.95), symptomatic hemorrhage rate (5 vs 2%, p=0.28), and favorable discharge location (85 vs 90%, p=0.32) did not differ.
Conclusions: A streamlined HMRI protocol permitted IV tPA administration to a small, but significant, subset of AIS patients initially deemed to have a SM.
Author Disclosures: M. Goyal: None. B. Hoff: None. J.A. Williams: None. J. Buck: None. L. Heitsch: None. P. Panagos: Speakers' Bureau; Modest; Genentech. K.D. Vo: None. T. Benzinger: None. C.P. Derdeyn: Ownership Interest; Modest; Pulse Therapeutics. Consultant/Advisory Board; Modest; Microvention, Penumbra, Silk Road, Pulse Therapeutics. J. Lee: None. A.L. Ford: None.
- © 2015 by American Heart Association, Inc.