Stroke: significance of baseline ischemic core volume for endovascular treatment outcomes in older stroke patients

Age and infarct volume are powerful factors
in predicting the prognosis of ischaemic stroke patients receiving endovascular therapy (EVT).
Scholars from the University of Calgary in Canada aimed to investigate the effect
of ischemic core volume (ICV) on stroke outcomes following EVT in older adults.

Using the HERMES (efficient reperfusion using multiple intravascular devices), the investigators conducted a patient-level meta-analysis of seven randomized trials enrolled between December 2010 and April 2015, dividing patients into patients aged < 75 years and ≥ 75 years
.
ICV is calculated based on computed
tomography perfusion or magnetic resonance diffusion-weighted imaging.
The relationship between ICV and the benefit of EVT relative to optimal drug therapy on outcomes (modified Rankin scale [mRS]) at 90 days and ICV thresholds
(≥90%) for high probability (mRS score ≥5) after EVT were investigated.

The results showed a total of 899 patients with baseline ICV data, 247 patients aged ≥ 75 years, of whom 118 were randomized to the EVT group
.
In the EVT group, patients aged ≥ 75 years required a smaller ICV to achieve an mRS score of ≤ 3 (median 10.
7 mL versus 23.
9 mL, P< 0.
001)
than those aged < 75 years.
In patients aged ≥ 75 years, outcome models in both treatment groups showed a potential loss
of EVT for achieving mRS scores ≤ 3 or ≤4 at ICV ≥ 50 mL or ≥85 mL.
The efficacy of EVT on mRS≤3 was significant at ICV < 50 mL (OR=2.
38, 95% CI 1.
35 to 4.
22).

ICV≥132 mL is the threshold
at which very poor results are likely to occur after EVT.
However, EVT can still predict mRS≤3 rates
of at least 30% at 150 ml of ICV if near-complete or complete reperfusion is achieved.

In summary, baseline ICV has an effect on stroke outcomes after EVT in older adults, but older patients with large ICV may still benefit
from EVT if near-complete or complete reperfusion is achieved.
Regardless of ICV status, younger patients appear to benefit
from EVT.

References:

Significance of Baseline Ischemic Core Volume on Stroke Outcome After Endovascular Therapy in Patients Age ≥75 Years: A Pooled Analysis of Individual Patient Data From 7 Trials