Abstract Body: BACKGROUND:
Nontraumatic intracerebral hemorrhage (ICH) especially in deep locations is independently associated with a long-term increased risk of major arterial ischemic events. Minimally invasive surgery (MIS) has not been shown to improve outcomes for deep ICH. Whether ischemic events modify the effect of MIS on outcomes for deep ICH has not been studied.
METHODS:
We pooled individual patient data from the MISTIE III (Minimally Invasive Surgery Plus Alteplase for Intracerebral Hemorrhage Evacuation Phase 3) and the ATACH-2 (Antihypertensive Treatment of Acute Cerebral Hemorrhage-2) trials. The exposure was ICH location (deep vs. lobar). The outcome was a symptomatic, clinically overt ischemic stroke or coronary ischemic event, adjudicated centrally within each trial. We evaluated the association between ICH location and risk of an ischemic event using Cox regression analyses after adjustment for demographics, vascular comorbidities, and ICH characteristics. We used logistic regression to assess whether ischemic events modified the effect of MIS with end of treatment volume (EOT) <15mL on modified Rankin scale (mRS) 0-3 at one year in MISTIE III.
RESULTS:
Of 1470 patients with ICH, mean age was 61.7 (SD, 12.8) years, and 574 (38.3%) were female. The median hematoma volume was 17.3 mL (interquartile range, 7.2–35.7) and 1186 (80.7%) were deep. During a median follow-up of 110 days (iqr 110-365), a total of 70 ischemic events occurred, 60 (5.0% cumulative incidence) in patients with deep ICH and 10 in patients with lobar ICH (cumulative incidence 3.2%). In adjusted analysis, deep ICH location, but not MIS was associated with increased risk of ischemic events (hazard ratio, 2.1 [95% CI, 1.07–4.3]). In the full MISTIE cohort, in patients without ischemic events during follow-up, MIS with EOT<15 mL was significantly associated with favorable one year outcome (OR 1.90 (95% CI: 1.16-3.12; Pinteraction = 0.04). There was no effect modification for deep location (Pinteraction = 0.13) and for lobar ICH, achieving EOT<15 with MIS was associated with good outcome regardless of ischemic events in adjusted analyses.
CONCLUSIONS:
In a heterogeneous cohort of patients with ICH, deep ICH location was associated with increased risk of ischemic events over the short term, but this appears to have low impact on one-year outcomes with successful surgery and does not help to explain worse outcomes of deep (vs. lobar) ICH with MIS.