Introduction Ischemic stroke is a devastating condition resulting in significant morbidity and mortality. Strong positive results of randomized trials have established mechanical thrombectomy as a mainstay for large vessel occlusive stroke, with significant improvements in functional outcomes. Our aim was to examine our thrombectomy procedures, and to evaluate relationships in practice change and development that could inform the adoption and selection of techniques.

Methods Retrospective review was conducted on mechanical thrombectomy cases from July, 2011 through December, 2015. Patients must have been 18 years old, diagnosed with ischemic stroke, and were treated with thrombectomy. Primary outcomes were time to recanalization, final TICI score, procedural complications, NIHSS improvement, mortality, and incidence of single pass thrombectomy.

Results 130 procedures were performed. 79.1% had a TICI score of at least 2b. Achieving a TICI score of 3 significantly improved over time (OR = 1.5, p = 0.004). 30% of thrombectomies were single pass. When evaluated by technique, single pass recanalization was achieved with reperfusion catheter alone in 52%, with stent-triever alone in 27%, and with combination techniques in 26% (Chi-squared 6.04, p = 0.048). In regards to technique used, 42.3% were a combination of reperfusion catheter and stent-triever, 19.2% were reperfusion catheter alone, and 31.5% were stent-triever alone. Procedural mortality was 0.77% (one patient). Improvement in NIHSS following thrombectomy became significantly better each year with the difference between NIHSS on discharge vs. on arrival dropping by -1.88 each year (p = 0.00416). Additionally, improvement in NIHSS had a significant inverse association with time to recanalization (p = 0.000398)

Conclusions: Preliminary data suggest that thrombectomy is a safe procedure that results in extremely low mortality and significant decreases NIH score over time, which may point to better functional outcome. Overall, there was an improvement in NIHSS reduction with time. Additionally, achieving faster times to recanalization resulted in better improvements in NIHSS. There was a significant difference in the ability of different techniques to achieve first-pass recanalization, though this may reflect clinical judgments about when to use each technique. Producing a TICI score of 3 also improved over time, demonstrating increased ability to recanalize at our institution over time.

Disclosures: S. Trott: None. O. Vsevolozhskaya: None. A. Alhajeri: None. J. Fraser: None.