Factors associated with early recanalization failure following intravenous rt-PA therapy for ischemic stroke.

BACKGROUND: Although intravenous recombinant tissue-type plasminogen activator (rt-PA) therapy can be effective for ischemic stroke, a considerable percentage of patients do not receive any benefit as a result of early recanalization failure. We aimed to investigate the factors associated with early recanalization failure following intravenous rt-PA therapy.

METHODS: Patients with acute ischemic stroke and internal carotid artery (ICA) or middle cerebral artery occlusion on initial magnetic resonance angiography (MRA) who received intravenous rt-PA therapy within 3 h of stroke onset and underwent follow-up MRA within 8 h after treatment were enrolled. Baseline characteristics, stroke features, onset to treatment time, initial National Institutes of Health Stroke Scale (NIHSS) score, initial Alberta Stroke Programme Early CT Score on diffusion-weighted imaging-ASPECTS (Alberta Stroke Program Early Computed Tomography Score), the presence of ICA or M1 origin (the residual length <5 mm) (ICA/M1 origin occlusion), initial vital signs, and laboratory findings were recorded. Early recanalization on the follow-up MRA within 8 h was evaluated by modified Mori grade: grade 0, no reperfusion; grade 1, movement of thrombus; grade 2, partial recanalization, and grade 3, complete recanalization.

RESULTS: Seventy subjects (35 women, 77 ± 12 years) were enrolled. The median (interquartile range: IQR) NIHSS score was 18 (12.5-24), and the mean onset to treatment time was 141 ± 54 min. ICA was occluded in 29%, M1 origin in 17%, M1 middle in 13%, M1 distal in 26% and M2 in 15%. The median (IQR) pretreatment diffusion weighted imaging-ASPECTS was 8 (6-9), and follow-up time of MRA was 65 min (59-70) after rt-PA therapy. Thirty-two subjects (46%) showed modified Mori grade 0; 10 (14%), grade 1; 9 (13%), grade 2, and 19 (27%), grade 3. Multivariate analyses revealed ICA/M1 origin occlusion (OR 3.71, 95% CI 1.03-14.87, p = 0.044), and C-reactive protein (per 0.1-mg/dl increment, OR 1.19, 95% CI 1.03-1.44, p = 0.013) were independently associated with subjects with no recanalization (grade 0-1), whereas age (per years old, OR 0.93, 95% CI 0.86-0.99, p = 0.014) and high-density lipoprotein cholesterol (per 1-mg/dl increment, OR 0.94, 95% CI 0.89-0.98, p = 0.004) were inversely associated with those.

CONCLUSION: ICA/M1 origin occlusion and C-reactive protein were positively and high-density lipoprotein cholesterol was negatively associated with early recanalization failure.