Middle cerebral artery pressure changes following Pipeline flow diversion

Objective Pipeline embolization devices (PED) are commonly used for endovascular treatment of cerebral aneurysms but changes in intracranial hemodynamics after PED deployment are poorly understood. Here, we assess middle cerebral artery (MCA) and systemic blood pressure before and after PED treatment. Methods Records of patients with cerebral aneurysms proximal to the internal carotid artery terminus treated with PED at our institution between 2015 and 2017 were retrospectively reviewed. Patients were included if ipsilateral MCA pressure measurements were available. Ipsilateral MCA pressure was transduced via the microcatheter before and after PED deployment. Systemic arterial blood pressure was also simultaneously recorded. MCA, systemic blood pressure, and ratios of MCA to systemic blood pressure values were compared before and after treatment among the study cohort using the two-sample paired Student t test. Results Fourteen patients were included. Mean age was 54 years. Among the entire cohort, the ratio of MCA to systemic systolic and mean blood pressure were significantly higher after treatment (respectively 0.76 vs. 0.69, p = 0.01, and 0.94 vs. 0.89, p = 0.03), and the ratio of MCA to systemic diastolic pressures showed an increasing trend (1.08 vs. 1.03, p = 0.09). The percentage of ratio increase was independent of aneurysm size ( r = -0.24, p = 0.42 for systolic ratio; r = -0.09, p = 0.74 for diastolic ratio; r = -0.09; p = 0.76 for mean ratio, respectively). Conclusions Following PED deployment, the ratio of ipsilateral MCA to systemic systolic and mean blood pressure increased. These pressure changes should be further evaluated in a larger sample size.