Failed mechanical thrombectomy: prevalence, etiology, and predictors.

OBJECTIVE: Despite advances in endovascular techniques, mechanical thrombectomy (MT) fails to achieve successful reperfusion in approximately 20% of patients. This study aimed to identify common etiologies and predictors of failed thrombectomy in a contemporary series. METHODS: A prospectively maintained database of MT patients between January 2013 and August 2021 was interrogated. Failed MT was defined as a final modified Thrombolysis in Cerebral Infarction score < 2b. Demographic data, procedural details, stroke etiology, and anatomical data in patients who underwent MT with subsequent failed reperfusion were collected. RESULTS: Of a total 1010 MT procedures, 120 (11.9%) were unsuccessful. The mean patient age was 66.8 years; 51.5% of patients were male, and 61.1% were White. The most common failure location was intracranial (93.3%) followed by failure at the arch (3.3%) and neck (3.3%). Among patients with intracranial failure, underlying intracranial atherosclerosis (ICAS) was the cause of failure in 84 patients (70%). Compared with patients with successful MT, patients with failed MT had a longer onset to puncture time (p = 0.012) and onset to groin time (p = 0.04). Rescue stenting was performed in 45 cases: 39 patients (4.4%) with successful MT and 6 (5.0%) with MT failure (p = 0.765). Multivariate analysis demonstrated that diabetes mellitus (p = 0.009) was independently associated with unsuccessful reperfusion. CONCLUSIONS: Failed MT was encountered in approximately 12% of MT procedures. The most common cause of failed MT was underlying ICAS. Further studies to evaluate better ways of early identification and treatment of ICAS-related large-vessel occlusion are warranted.

Initial Experience in Direct Aspiration Thrombectomy Using a Novel 0.071-Inch Aspiration Catheter.

INTRODUCTION: A Direct Aspiration First Pass Technique is one of the most widely used techniques in mechanical thrombectomy. Aspiration catheter size plays a major role in the success of this technique. The AXS Vecta (Stryker Neurovascular, Fremont, California, USA) aspiration catheter is the first approved 0.071-inch catheter for mechanical thrombectomy. Here, we report our initial experience with direct aspiration thrombectomy using the AXS Vecta aspiration catheter. METHODS: We reviewed the prospectively collected database of all consecutive patients with stroke who underwent thrombectomy using A Direct Aspiration First Pass Technique with the AXS Vecta aspiration catheter at our institution between September 26 and October 12, 2018. RESULTS: A total of 10 thrombectomy procedures were performed. Of those, 3 patients had M1 occlusion, 6 patients had M2 occlusion, and 1 patient had cervical carotid + M1 tandem occlusion. Modified Thrombolysis in Cerebral Ischemia grade 2b or greater revascularization was obtained in 9 of 10 patients. Median groin-to-reperfusion time was 29.5 (interquartile range 14.25-53.25) minutes. An intermediate catheter (3 Max) was used in all cases. No procedural complications or vascular injury were identified. The AXS Vecta catheter demonstrated excellent tractability and navigability in all cases except 1 case with severe narrowing of M1 segment secondary to atherosclerosis. CONCLUSIONS: In this early experience with the new AXS Vecta aspiration catheter, the catheter was safely navigated to the target vessel even at the level of M2 segment.