Effectiveness and safety of EVT in patients with acute LVO and low NIHSS

There is much uncertainty in endovascular treatment (EVT) decisions in patients with acute large vessel occlusion (LVO) and mild neurological deficits.

From a prospective, nationwide stroke registry, all patients with LVO and baseline NIHSS <6 presenting within 24 h from the time last known well (LKW) were included. Early neurological deterioration (END) developed before EVT was prospectively collected as an increasing total NIHSS score ≥2 or any worsening of the NIHSS consciousness or motor subscores during hospitalization not related to EVT. Significant hemorrhage was defined as PH2 hemorrhagic transformation or hemorrhage at a remote site. The modified Rankin Scale (mRS) was prospectively collected at 3 months.

Among 1,083 patients, 149 (14%) patients received EVT after a median of 5.9 [3.6-12.3] h after LKW. In propensity score-matched analyses, EVT was not associated with mRS 0-1 (matched OR 0.99 [0.63-1.54]) but increased the risk of a significant hemorrhage (matched OR, 4.51 [1.59-12.80]). Extraneous END occurred in 207 (19%) patients after a median of 24.5 h [IQR, 13.5-41.9 h] after LKW (incidence rate, 1.41 [95% CI, 1.23-1.62] per 100 person-hours). END unrelated to EVT showed a tendency to modify the effectiveness of EVT (P-for-interaction, 0.08), which decreased the odds of having mRS 0-1 in mild LVO patients without END (adjusted OR, 0.63 [0.40-0.99]).

The use of EVT in patients with acute LVO and low NIHSS scores may require the assessment of individual risks of early deterioration, hemorrhagic complications and expected benefit.