Abstract Body: Background: The Early MiNimally-Invasive Removal of ICH (ENRICH) trial established minimally invasive surgical evacuation as an effective therapy for acute, spontaneous, lobar intracerebral hemorrhage (ICH). We aimed to estimate the annual number of US patients in 2020 eligible for minimally invasive hematoma evacuation by extrapolating Greater Cincinnati Northern Kentucky (GCNK) Stroke Study epidemiologic data to US census data.
Methods: We ascertained all adults (>18 years) with acute (<24 hours from last known well), spontaneous ICH presenting to the ED in GCNK in 2015. Cases were identified by ICD codes, clinical data abstracted, and physician adjudicated. The location and volume of ICH was centrally adjudicated by neuroradiologists. We calculated conservative and liberal estimates of the number of GCNK patients with acute, spontaneous, lobar ICH that met ENRICH trial eligibility for minimally invasive surgical evacuation. Lobar ICH was analyzed separately given the benefit of surgical hematoma evacuation was attributable to intervention for lobar ICH in ENRICH. Conservative estimates considered all clinically relevant ENRICH trial eligibility criteria. Liberal estimates removed anticoagulant use as exclusion criterion because these patients were included in ENRICH if coagulopathy was rapidly reversed. The derived estimates of ENRICH eligible patients were then extrapolated to the 2020 US adult population using characteristics of ICH patients in GCNK and 2020 US census data.
Results: Over the 2015 GCNK study period, 197 patients with acute, spontaneous ICH were identified (median age 74, 55% female, 28% Black). In conservative estimates applying all clinically relevant ENRICH criteria, 5.7% (n=6) of lobar ICH patients were eligible for minimally invasive surgical evacuation. Including those on anticoagulants resulted in 6.7% (n=7) of lobar ICH patients being eligible for minimally invasive surgical evacuation. After extrapolation to the 2020 US population, of an estimated 96,120 ICH cases in 2020, we calculated that 1,972 (conservative) to 2,318 (liberal) patients with acute lobar ICH would be eligible for minimally invasive surgical evacuation based on ENRICH eligibility criteria (Figure 1).
Conclusion: It is estimated that 1,972-2,318 acute, spontaneous, lobar ICH patients in the US in 2020 met eligibility for minimally invasive surgical hematoma evacuation. US stroke systems of care should be designed to meet the demand for this new therapy.