Abstract TP300: Passing Extracranial Artery Occlusion by Intermediate Catheter with Expanding Microballoon (PEACE): A Novel Endovascular Therapy for Posterior Circulation Tandem Lesions (PCTLs)

Background: Posterior circulation acute ischemic stroke (AIS) accounts for ~20% of all AIS cases and is associated with high rates of mortality and disability. Posterior circulation tandem lesions (PCTLs) represent a particularly challenging subtype, given atypical clinical presentation and complex vascular anatomy, and remain associated with poor clinical outcomes. The optimal endovascular treatment strategy remains uncertain. Rapid and safe traversal of extracranial occlusions is critical to enable timely intracranial recanalization. In anterior circulation tandem lesions (ACTLs), we developed the PEACE technique to address this challenge, which demonstrated high recanalization rates and favorable outcomes in ACTLs. This study evaluated the safety, feasibility and comparative efficacy of PEACE in PCTLs. Methods: Endovascular treatment was performed on 29 patients with acute ischemic stroke with PCTLs, of whom, 19 were treated using PEACE. In this approach, a microballoon was used to facilitate rapid and safe passage of an intermediate catheter across the extracranial lesions, minimizing forward flow and distal embolization. Intracranial recanalization was primarily achieved by aspiration, with angioplasty and stenting performed for basilar or vertebral artery lesions when indicated. Results: As compared with previous studies of PCTLs, the PEACE technique achieved shorter recanalization time, higher reperfusion rates, and improved outcomes (Table 1). Median puncture-to-recanalization times in prior reports typically ranged from 57 to 130 minutes, whereas the PEACE group achieved 55 minutes. All PEACE cases (100%) achieved successful reperfusion (TICI ≥2b), exceeding the pooled rate of 87.7% in previous cohorts. Favorable 90-day outcome (mRS 0–2) was achieved in 63.2% with PEACE as compared with 33.7% in earlier studies. Mortality was lower with PEACE (10.5% vs 34.8%), while symptomatic intracranial hemorrhage(sICH) was similar (5.3% vs 6.5%). Conclusion: PEACE provides a novel endovascular solution for PCTLs, combining expanding microballoon-assisted access with aspiration-based clot removal to achieve rapid, complete recanalization while minimizing distal embolization. By delivering markedly better functional outcomes and survival compared to prior approaches, PEACE represents a safe, feasible, and potentially practice-changing strategy for complex posterior circulation strokes. Larger multicenter validation is warranted.