1252. Use of Instantaneous Wave Free Ratio to Guide Intracranial Angioplasty

Authors: Muhammad Waqas, MBBS; Kunal Vakharia; Amanda Young; Najya Fayaz; Hussain Shallwani; Jason Davies; Kenneth Snyder; Elad Levy; Adnan Siddiqui (Buffalo, NY)

Introduction: The degree of anatomical narrowing does not always correlate with the amount of blood flow across the area of stenosis. Fractional flow reserve (FFR) and instantaneous wave free ratio (IFR) measurements pre and post angioplasty plasty provide an objective estimate of flow across the area of stenosis and have become gold standard for percutaneous coronary interventions. In this study we have described the feasibility of use of IFR for intracranial angioplasty. Methods: This was a case series of consecutive patients treated with intracranial angioplasty with IFR before and after the angioplasty with Volcano pressure wire. The study was approved by institutional review board. We collected patient data on age, gender, comorbid conditions, presenting complaints, modified Rankin score at presentation, neurological findings, procedure duration, intra-operative complications length of hospital stay and modified Rankin score (mRS) at one month and last follow up. Degree of stenosis and IFR values before and after angioplasty were recorded. Results: Twelve patients underwent IFR guided angioplasty during the study period. Median age of patients was 70 years (range 48-81 years). All the patients had symptomatic disease. Three patients had basilar artery while, 2 had vertebral artery stenosis. Six patients underwent angioplasty for MCA, 1for ICA, 2 for vertebral artery, and 3 for basilar artery stenosis. The degree of stenosis ranged from 55% to 90%. The average improvement in the degree of stenosis was 15.92±9.98%. A significant improvement in IFR value was seen in all the patients. No procedure related complication were reported. Median follow was 11 months. Favorable outcomes defined as mRS 0-2 were seen in 10 patients Conclusion: IFR measurement before and after intracranial angioplasty is safe and feasible. It may be used as an endpoint for angioplasty and guide the aggressiveness of the procedure.