Abstract WP7: Mstu Validation Of A Pre-reperfusion Map For Better Thrombectomy Outcomes

Abstract

Background: We sought to determine and validate a pre-reperfusion blood pressure threshold for MCA occlusions patients with better thrombectomy outcomes. Methods: We reviewed patients from 2013 to 2015 treated with thrombectomy for a MCA M1 occlusion at our center. Blood pressure measurements from available records at the time of EMS activation to the time of reperfusion were used to calculate an averaged pre-reperfusion mean arterial pressure (MAP). All patients in our analysis had successful reperfusion. Our endpoint was a mRS ≤2 at 90 days. The averaged MAP was grouped as follows: ≥85mmHg, ≥90mmHg, ≥95mmHg, ≥100mmHg, ≥110 mmHg and ≥115mmHg. We considered hourly epochs from symptom onset to reperfusion, pre-treatment ASPECTS, thrombolytics, and collateral status. Significant parameters from a univariate analysis were included into a multivariate logistic regression to determine independent predictors of outcome. The multivariate findings were then validated with a prospective set of similar patients evaluated with our mobile stroke treatment unit. Results: We reviewed 52 patients. Mean age was 70; NIHSS was 16±6; 40% (21) received t-PA; median ASPECTS score was 10; TICI 3 score was achieved in 63% (33), and 67% (35) had a good outcome. The number of patients having a mean arterial blood pressure threshold were as follows: ≥85mmHg (96%), ≥90mmHg (83%), ≥95mmHg (73%), ≥100mmHg (58%), ≥110mmHg (31%) and ≥115mmHg (15%). Reperfusion occurred as follows: ≤3hrs (4%), ≤4hrs (21%), ≤5hrs (39%), ≤6hrs (52%), ≤7hrs (67%), ≤8hrs (79%), ≤9hrs (87%), and ≤12hrs (90%). Our multivariate logistic regression model identified an average pre-reperfusion MAP ≥95mmHg as the sole factor statistically associated with a better outcome post successful thrombectomy [OR 15.1, CI 1.3-170.1,p=0.02]. Good clinical outcome in those patients with an averaged MAP ≥95mmHg was 76% and 43% in those below the threshold [OR 5.2, p=0.02]. Our validation cohort consisted of 32 patients, and a pre-reperfusion averaged MAP ≥ 95 mmHg had a sensitivity of of 93% for a good outcome. Conclusion: Our analysis suggests with validation that a pre-reperfusion averaged MAP ≥ 95mmHg results in better outcomes with successful thrombectomy and may be used as a therapeutic target in the pre-hospital setting.