VIENNA – Reperfusion within 6 hours of a stroke proved to be a better predictor of both imaging and clinical outcomes than recanalization in an analysis of patients included in a multicenter, prospective, longitudinal study.
Indeed, when reperfusion was achieved, penumbra salvage was more likely (P < .0001), there was less lesion growth (P = .0002), and a smaller overall infarct size (P < .0001).
“Early revascularization is the main therapeutic goal in ischemic stroke as it can reduce infarct growth and improve clinical recovery,” said Tae-Hee Cho, Ph.D., who presented the research at the annual European Stroke Conference.
Dr. Cho of Hôpital Neurologique Pierre Wertheimer in Lyon, France, noted that reperfusion and recanalization are often closely related but can be disassociated with one occurring without the other. Although prior studies have looked at which might be a better marker for poststroke outcomes, later time windows were involved, so the aim of the present research was to look at an earlier point in time.
The I-KNOW European consortium database was used to identify patients with acute ischemia in the anterior circulation who had a confirmed occlusion on magnetic resonance angiography (MRA) and in whom reperfusion and recanalization had been assessed on a repeat scan, either within 6 hours of symptom onset if intravenous tissue plasminogen activator (tPA) was used or within 12 hours if no tPA was given.
Of 168 patients included in the database, 46 had the necessary data and were analyzed. The median age of the included patients was 69 years (range, 64-74). The majority was male (61%), with a median lesion size of 18.9 mL measured using diffusion-weighted magnetic resonance imaging.
At admission, the middle cerebral artery was occluded at M1 in 15 patients, 22 had M2 occlusion, 9 had M3 occlusion, and 1 patient had A1 occlusion. The median penumbra volume was 13.3 mL.
“Reperfusion and recanalization were assessed within 6 hours in all patients,” Dr. Cho observed. The median delay was 302 minutes, he added.
Results showed that reperfusion occurred in 27 (59%) patients and recanalization in 19 (41%) patients. Around 30% achieved reperfusion without recanalization, but the latter didn’t occur if reperfusion was not present.
“All imaging events were significantly improved by reperfusion,” Dr. Cho reported. This was not seen with recanalization, he observed. A similar pattern was seen for favorable clinical responses, which was defined as a fall of 8 points or a score of 0-1 on the National Institutes of Health Stroke Scale.
Dr. Cho noted that the research, which was published in Stroke just before the conference, showed that reperfusion within 6 hours of symptom onset was better than recanalization at predicting imaging outcomes and that it might be a reliable surrogate for clinical outcome.
Dr. Jenny Tsai and Dr. Gregory Albers of the Stanford Stroke Center in Palo Alto, Calif., commented on the data independently in an editorial accompanying the published paper, noting, “Optimal stroke therapy should result in both recanalization and reperfusion.”
They suggested that the higher rate of reperfusion than recanalization in the study is perhaps not unexpected “because recruitment of collateral circulation can occur rapidly in the setting of an acute vessel obstruction.”
They also observed that, while the findings suggest that reperfusion is of greater physiologic importance, these are not discrete or static entities. Imaging provides “a snapshot of an evolving process” and “an occluded vessel at a moment in time does not imply that beneficial recanalization did not occur subsequently.”
However, the editorialists concluded that, “if you must choose one, we agree with Cho et al.: the Oscar goes to reperfusion.”
Dr. Cho and Dr. Tsai had no disclosures. Dr. Albers is an equity shareholder in iSchemaView.