The goal of the study was to evaluate the association between last known normal-to-puncture time and favorable neurological outcome on discharge.

Mechanical thrombectomy (MT), an established treatment for acute ischemic stroke due to proximal anterior circulation large vessel occlusion, has been shown to help patients achieve functional independence. The effect of time to treatment based on specific treatment time-frames and ASPECTS has not been established.

We conducted a retrospective cohort study collecting data prospectively on patients who underwent MT. We used binary logistic regression models adjusted for age, mTICI score, initial NIHSS, and ASPECTS to assess the association between LKN-to-puncture time and favorable neurological outcome defined as mRS 0-2 on discharge. Treatment times were discretized into fifteen minute intervals. Patients were excluded if they were missing a LKN time, puncture time, or mRs score on discharge.

Among 421 patients, 93 patients were missing data for inclusion criteria. 328 patients were included in the analysis. Increased LKN-to-puncture time was associated with a decreased probability of achieving mRS 0-2 (aOR ratio per 15 minute delay 0.98; 95% confidence interval, 0.97-0.99, p =0.001). This was especially true when LKN-puncture time was 0-6 hours (aOR per 15 minute delay 0.94; 95% confidence interval 0.89-0.99, p = 0.05) or ASPECTS 8-10 (aOR 0.98, 95% confidence interval 0.97-0.99, p=0.002 ) as opposed to when LKN-puncture time was 6-24 hours (aOR per 15 minute delay 0.99 ; 95% confidence interval 0.97-1.00, p=0.16 ) and ASPECTS < 8 (aOR 0.98, 95% confidence interval 0.93-1.03, p= 0.37).

Decreased LKN-groin puncture time improves outcome particularly in those with good ASPECTS presenting within the first 6 hours. Neuroprotective therapy and strategies to decrease reperfusion times should be investigated to reduce infarct growth and improve outcomes.