Features of Patients With Stroke Receiving Intracranial Balloon Angioplasty for Secondary Prevention in Comparison to Rescue Recanalization.

Background: Susceptibility to intracranial atherosclerosis is a unique feature of stroke in Asian patients. Intracranial percutaneous transluminal balloon angioplasty/stenting (IC-PTAS) is an important therapy for secondary prevention and rescue in such patients. Objective: The purpose of this study is to clarify features of Japanese patients with stroke receiving IC-PTAS for secondary prevention or for rescue recanalization. Methods: Medical records of 116 consecutive stroke patients treated with IC-PTAS at our hospital from April 2006 to May 2018 were retrospectively reviewed. The patients were divided into secondary prevention (P) and rescue (R) groups based on the purpose of IC-PTAS. Backgrounds, procedures, andtechnical and clinical outcomes were compared between the groups. Results: In groups P (n=60, male=40) and R (n=56, male=35), the mean ages were 70 and 72 years, the median times from ischemic events to IC-PTAS were 21 and 0.5 days, the mean stenotic ratios were 84.6% and 97.9%, the number of cases with morphology suitable for IC-PTAS (modified Mori class A or B1) were 35 and 8, and the distributions of treated vessels (extradural ICA, intradural ICA, MCA, BA, VA, others) were 31, 6, 11, 5, 5, 2, and 4, 14, 24, 6, 5, 3, respectively. In groups P and R, stents were deployed in 26 (43%) and 23 (41%) cases, technical success was achieved in 60 (100%) and 48 (86%) cases, the mean residual stenotic ratios were 27.6% and 40.3%, and there were major complications in 4 (7%) and 6 (12%) cases, stroke within 30 days in 4 (7%) and 6 (12%) cases, and symptomatic intracranial hemorrhage in 0 and 1 cases, respectively. Conclusion: Stroke patients receiving IC-PTAS for secondary prevention in Japan have a longer interval between the ischemic event and the procedure and a higher number of safer lesions, such as those with a lower stenotic ratio, suitable morphology, and an intradural site, compared to patients who receive this treatment for rescuerecanalization. This might result in favorable technical and clinical outcomes for patients receiving IC-PTAS in Japan.