Minimally Invasive Surgery More Effective than Medical Management for Intracerebral Hemorrhage According to ENRICH Study Results in NEJM

According to results from the ENRICH clinical trial (NCT02880878) published in The New England Journal of Medicine, people with an intracerebral hemorrhage removed via minimally invasive surgery within 24 hours had better functional outcomes at 180 days compared with those receiving guideline-based medical management alone. The difference in functional outcomes was especially pronounced in people with lobar hemorrhage. Additionally, the percentage of individuals who died within 30 days of intracerebral hemorrhage was nearly 2-times higher in people who received only medical management.

ENRICH was a prospective, multicenter, adaptive, randomized trial that included 300 people with acute intracerebral hemorrhage from 37 centers in the United States. Participants were randomly assigned to receive either minimally invasive surgical removal of the hematoma using Nico Corporation’s BrainPath and Myriad Technology (Indianapolis, IN) along with medical management (n=150) or medical management alone (n=150). Participants in both assigned groups had similar demographic and baseline characteristics.

Of the 300 total participants, 30.7% had anterior basal ganglia hemorrhages and 69.3% had lobar hemorrhages. The primary efficacy endpoint was the mean score on the utility-weighted modified Rankin scale (mRS) at 180 days, with secondary endpoints measuring safety outcomes, including mortality at 30 days after intracerebral hemorrhage. 

At 180 days, the posterior probability of superiority for surgical intervention + medical management versus medical management alone was .981, with participants showing a utility-weighted mRS mean score of:

• .458 in the surgery and medical management group
• .374 in the medical management group

The mean between-group difference was:

• .127 for people with lobar hemorrhage (95% Bayesian credible interval, .035 to .219)
• .013 for people with anterior basal ganglia hemorrhage (95% Bayesian credible interval, -.147 to .116)

At 30 days, the percentage of participants who died was:

• 9.3% for those receiving surgery and medical management

18.0% for those receiving medical management only

“ENRICH is the first, randomized clinical trial to meet its primary endpoint, while improving outcomes for these deadly strokes,” said Gustavo Pradilla, MD, co-lead investigator for ENRICH and Associate Professor of Neurosurgery at Emory University School of Medicine, regarding initial data from the trial which was presented at the American Association of Neurological Surgeons (AANS) meeting in 2023. “This trial will help to change how we treat hemorrhagic stroke moving forward.”