Reperfused Penumbral Volume Predicts Outcomes in Acute Ischemic Stroke
The goal for intravenous therapy in patients with acute ischemic stroke is rescuing the ischemic penumbra from infarction.
Reperfused penumbral volume offers prognostic utility for early and late clinical outcomes in alteplase-treated patients with acute ischemic stroke, according to findings from a registry-based study published in Stroke.
Investigators analyzed data from 1507 patients with acute ischemic stroke who were included in INSPIRE (International Stroke Perfusion Imaging Registry). The volume of reperfused penumbra was able to predict 90-day modified Rankin Scale 0 to 1 (area under the curve [AUC], 0.77; R², 0.28; P <.0001). Additionally, adjustment for baseline ischemic core volume demonstrated that reperfused penumbral volume provided strong prognostic value for good functional outcome (AUC, 0.946; R², 0.55; P <.0001).
According to the investigators, with each 1% increase in penumbral reperfusion volume, patients had a 7.4% increase in the odds of achieving an excellent outcome at 90 days. The degree of reperfused penumbra was also related to an improvement in acute 24-hour National Institutes of Health Stroke Scale (R², 0.31; P <.0001), a correlation that was stronger following baseline ischemic core volume adjustment (R², 0.41; P <.0001).
Researchers also discovered that if >20 mL of penumbra is salvaged, the chance of a good clinical outcome with complete reperfusion is >80%. No penumbral reperfusion, however, lowers the probability to 6%. Investigators suggest that this information may be helpful for clinical decision making.
One of the limitations of this study was the lack of readily available endovascular treatment and the inclusion of only patients treated with intravenous therapy. The investigators suggest that data from patients who received endovascular treatment would validate their current findings because endovascular therapy leads to more complete reperfusion.
Investigators suggest that these findings “indicate that penumbra salvaged is an important metric to predict individual patient outcome which can be used to measure benefit from therapy” in clinical practice.
Chen C, Parsons MW, Clapham M, et al. Influence of penumbral reperfusion on clinical outcome depends on baseline ischemic core volume. Stroke. 2017;48(10):2739-2745.