Abstract TP335: Comparative Impact of Timing From Ictus to Intracerebral Hemorrhage Evacuation on Outcome in MISTIE III, STICH I & II Trials

Abstract

Introduction: Completion of the MISTIE procedure requires a period of hematoma stability before and during hematoma removal and, if necessary, dosing of rtPA which can take days to complete. Early surgery was intended in the STICH I and II trials, yet was performed after varying delays. No previous analysis has evaluated the timing for hematoma removal on outcomes in these trials. Objective: Determine if time from ictus to completion of hematoma removal may have affected patient outcome in three large surgical clinical trials of ICH evacuation. Methods: Patients randomized to surgery in the MISTIE III (n=242), STICH I (n=464) and STICH II (n=266) trials who received the procedure were analyzed, excluding cases crossing over to surgery. Time from ictus to end of treatment, defined as 24 hours after last dose in (MISTIE III) or time to craniotomy (STICH I and II), was analyzed in relation to likelihood of survival and functional outcome at 180 days. Cubic spline models with dichotomized outcomes were used. Results: The probability of achieving an mRS 0-3 increased significantly with longer time until completion of the procedure, up to 83 hours post-ictus, and worsened with longer delays thereafter (p=0.05). Better mRS was also achieved in STICH I patients with longer time until surgical removal, up to 60 hours post-ictus (p=0.0002), but not with longer delays (p=0.49). In STICH II (lobar cases), there was greater likelihood of mRS 0-3 with longer delay after 22 hours post-ictus (p=0.004), but not with earlier surgery (p=0.19). There was no significant benefit in survival, with earlier intervention across modalities and trials. Adjustment by initial hematoma volume further validated that early procedures do not favor survival or achieving a mRS 0-3. Conclusion: Early hematoma evacuation up to 60-80 hours post-ictus does not increase the probability of survival nor a good functional outcome in non-herniating ICH patients included in clinical trials, likely in view of bleeding instability. This was true in minimally invasive intervention as well as open surgeries.