Abstract 3198: Procedural Outcomes in Mechanical Thrombectomy for Acute Stroke: Atrial Fibrillation Predicts Single Device Therapy

Abstract

Background Timely and efficient reperfusion is associated with better outcome from acute cerebral ischemia. The predictors of procedural success in patients treated with multimodal mechanical device strategies (Merci ± Penumbra ± angioplasty and stenting) have not been well delineated. Methods In a prospectively maintained database, we analyzed consecutive patients with acute ICA and M1 occlusions treated with endovascular recanalization following multimodal MRI. We investigated the pretreatment clinical and imaging factors affecting three procedural outcomes: number of passes, single device-type therapy, and presence of SAH after the procedure. We also sought to determine the relationship between these procedural variables with substantial recanalization (TICI≥2b) and clinical outcome. Results Among 105 patients meeting study entry criteria, mean age was 66.6 (±17.8), 65% were female and 34% had history of atrial fibrillation. The median pretreatment NIHSS was 18 (range 2-31), mean baseline DWI volume was 30.6cc (SD±35.1), and mean time to groin puncture was 412min (SD±207.6). The median number of mechanical device passes was 2 (range 0-8). 73 (70%) patients were treated with a single device. IV tPA was used in 43 patients (41%). Substantial recanalization occurred in 43 patients (41%). In the final binary logistic regression multivariate analysis, among all baseline clinical and imaging variables, history of atrial fibrillation was the most significant factor associated with a single device therapy (OR 0.249; p=0.024). Age, gender, baseline DWI volumes, arterial occlusion site and time to recanalization did not correlate with the number of attempts, single or multiple device usage, or presence of SAH after the procedure. None of the procedural or baseline variables correlated with recanalization rates. The strongest predictors of poor outcome (mRS≥3 at discharge) were high baseline NIHSS (OR 0.87; p<0.001) and presence of SAH after the procedure (OR 0.05; p=0.001). However, the presence of SAH did not correlate with the number of attempts or devices used. Conclusions: A history of atrial fibrillation predicts single device usage in mechanical thrombectomy for acute ischemic stroke treatment. This is likely due to the fibrin-rich histological composition of the clot. In contrast to prior studies involving a single type of device, increased number of passes with multiple different mechanical devices was not associated with lower recanalization rates and did not worsen clinical outcome.