Contrast Neurotoxicity and its Association with Symptomatic Intracranial Hemorrhage After Mechanical Thrombectomy

Purpose: Despite improved techniques and sophisticated postinterventional care, symptomatic intracranial hemorrhage (sICH) remains the most feared complication of mechanical thrombectomy (MT). Based on peri-interventional parameters, we aimed to discover which patients have a higher risk of sICH.

Methods: From March 2017 until March 2020 consecutive patients with acute ischemic stroke (AIS) and confirmed large-vessel occlusion who underwent MT were analyzed retrospectively. Demographic, clinical, and radiological variables and parameters specific to thrombectomy were reviewed. A univariate analysis was performed and statistically significant variables were included in a logistic regression model to identify independent factors predictive of sICH.

Results: A total of 236 patients with confirmed large-vessel occlusion were included and 22 (9.3%) had sICH. Univariate predictors of sICH included diabetes mellitus, glucose > 11.1 mmol/L, creatinine clearance (CrCl) ≤ 30 ml/min/1.73, ASPECTS indicating pretreatment infarct size, acute internal carotid artery (ICA) occlusion, stent implantation, tirofiban use, time from symptom onset to groin puncture > 4.5 h and high contrast medium consumption. In the adjusted analysis, ASPECTS < 6 (OR 3.673, p = 0.041), and amount of contrast injected ≥ 140 ml (OR 5.412, p = 0.003) were independent predictors of sICH, but not any more baseline glucose > 11.1 mmol/L (OR 1.467, p = 0.584), CrCl ≤ 30 ml/min/1.73 (OR 4.177, p = 0.069), acute ICA occlusion (OR 2.079, p = 0.181), stent implantation (OR 0.465, p = 0.512), tirofiban use (OR 5.164, p = 0.167), and time from onset-to-groin puncture (OR 1.453, p = 0.514).

Conclusion: The amount of contrast medium used is a modifiable factor associated with sICH. This association is novel and may be related to the neurotoxicity of the contrast medium disrupting the blood-brain barrier.