The Source for Neurovascular News and Education

November 29, 2022

In the DEFUSE 3 trial, the improvement correlated with favorable clinical and radiographic outcomes and shorter hospital stays.


Rapid neurological improvement is a strongly positive prognostic sign for patients with stroke due to large-vessel occlusion who undergo thrombectomy in late time windows, just as it is in early time windows, a new study shows.


The findings, from an analysis of the DEFUSE 3 data, were published online April 1, 2019, ahead of print in Stroke.


“We’ve learned from earlier-window trials for thrombectomy in patients who are treated up to 6 hours from when their symptoms started that, if you treat a patient [with thrombectomy] and then the next morning their symptoms have improved significantly. . . . When you look out longer term, those patients do really, really well,” lead author Jeremy J. Heit, MD, PhD (Stanford University School of Medicine, Stanford, CA), told Neurovascular Exchange in an interview. “The question is: is it different when you are looking at [patients treated in] these very late time windows?”


Heit et al used the DEFUSE 3 data set to evaluate the prognostic value of rapid neurological improvement, defined as a reduction of ≥ 8 on the NIHSS or a score of 0 to 1 at 24 hours after thrombectomy. All patients were treated with thrombectomy more than 6 hours after the first signs of an acute ischemic stroke.


Overall, 91 patients in DEFUSE 3 underwent thrombectomy and had follow-up data available. Of these patients, 34% experienced rapid neurological improvement after thrombectomy. Patient demographics as well as stroke presentation and imaging details were similar between those who did and did not experience rapid neurological improvement.


Rates of reperfusion, defined as a TICI score 2b-3 after thrombectomy, and of symptomatic intracranial hemorrhage were similar for both groups (P = 0.2 for both comparisons).


On the other hand, patients who experienced rapid neurological improvement had a more favorable 90-day mRS shift (OR 3.8; 95% CI 1.7-8.6; P = 0.001). In addition, a higher proportion of these patients achieved an mRS 0-2 (OR 2.7; 95% CI 1.1-6.7; P = 0.03).


Mortality rate, median 24-hour NIHSS, 24-hour infarct volume, and 24-hour infarct growth were all lower for patients who showed rapid neurological improvement. These patients also had shorter hospital stays.


Outcomes by Presence of Rapid Neurological Improvement



(n = 31)


(n = 60)

P Value

Median 90-Day mRS (IQR)

2 (1-3)

3.5 (2-5)


mRS 0-2




Median NIHSS



< 0.001

Median 24-Hour Infarct Volume, mL



< 0.001

Median 24-Hour Infarct Growth, mL



< 0.001

Median Hospital Stay, days



< 0.001


An important implication of these findings, said Heit, is that they allow physicians to reassure those who recover quickly from a stroke, and their families, that the long-term prognosis will likely be excellent—even if they were treated outside the 6-hour time window.


He added the study can also inform stroke trial research.


“If you’re doing the next big stroke study and budgets get cut, what you really would like is an earlier predictor of good outcome,” Heit said, adding that rapid neurological improvement might serve as a reliable proxy for 90-day mRS. Finally, prognostic markers like this, he noted, are useful for streamlining posthospitalization care, which can ultimately lower healthcare costs related to stroke.



Heit JJ, Mlynash M, Kemp SM, et al. Rapid neurologic improvement predicts favorable outcome 90 days after thrombectomy in the DEFUSE 3 study. Stroke. 2019;Epub ahead of print.



Heit reports consulting for Medtronic and MicroVention, and serving on the medical and scientific advisory board for iSchemaView.