Abstract TP19: Impact of Revascularization Therapy on Patient Outcome by the Severity of Acute Ischemic Stroke

Abstract

Background and Purpose: It has not fully investigated whether the benefit from revascularization therapy for patients with mild acute ischemic stroke (AIS) can overweigh the risk. The aim of this study was to investigate the impact of revascularization therapy on patient outcome as related to the severity of the stroke. Methods: From our hospital’s stroke database from January 2006 to March 2017, we extracted data for patients with AIS. Eligible criteria for the patients were: modified Rankin Scale (mRS) of 0 or 1 before onset, admitted less than 24 hours after onset, and followed up for at least 3 months. Revascularization therapy included intravenous tissue plasminogen activator; endovascular therapy (intra-arterial urokinase infusion, percutaneous transluminal angioplasty, emergent carotid artery stenting, and thrombectomy); and carotid endarterectomy performed within 14 days from onset. Patients were divided into 4 groups based on the severity using the National Institutes of Health Stroke Scale (NIHSS) on admission : Group 1 = 0-4, Group 2 = 5-9, Group 3 = 10-19, and Group 4=20-. We defined a good outcome as mRS score of 0-1 at 3 months after onset. The odds ratio of a good outcome was computed among 4 groups, adjusting for age and sex. Results: We extracted data for 3275 patients with AIS (71.3 years, 65.1% men). Of these, 17.9% received revascularization therapy of any type. This was distributed across the 4 NIHSS groups as follows: 6.1% of Group 1 (n=2193), 27.1% of Group 2 (n=527), 56.4% of Group 3 (n=298), and 55.6% of Group 4 (n=257). The odds ratios (95% confidence interval) of treatment for good outcome in group 1 to 4 were 0.42 (0.29-0.62), 1.15 (0.78-1.72), 2.80 (1.60-4.90), and 4.40 (1.79-10.82), respectively. Group 1 was further divided into 5 subgroups by each NIHSS scores of 0-4. The odds ratios for each subgroup (NIHSS scores 0, 1, 2, 3, and 4) were 0.20 (0.07-0.61), 0.28 (0.11-0.69), 0.27 (0.11-0.69), 0.93 (0.43-2.03), and 0.88 (0.42-1.85), respectively. Conclusions: Approximately half of the patients with NIHSS score of ≥10 received revascularization therapy and had significant benefit. However, revascularization therapy for patients with mild AIS (specifically NIHSS scores of 0, 1, or 2) could be rather harmful.