Blood Pressure After Endovascular Stroke Therapy-II: A Randomized Trial

Several thousand patients suffer from an ischemic stroke caused by an occlusion of a large blood vessel supplying the brain. Endovascular mechanical thrombectomy (EVT) has revolutionized management of this most devastating type of ischemic stroke by allowing removal of the occlusive clot. However, about half of the successfully EVT-treated patients (~85% of all treated patients) still remain disabled at 90 days. Early evidence suggests that patients with lower blood pressure (BP) after the thrombectomy procedure have better outcomes. However, safety of lowering BP in these patients has not been determined. The primary safety concern of lowering BP comes from the potential of compromising blood flow to the "at risk" area of the brain following the stroke.

The purpose of this trial is to evaluate the safety of lower BP management strategies in patients who are successfully treated with endovascular treatment for ischemic stroke. The investigator will enroll 120 individuals who qualify and randomly assign them to one of the three systolic BP (SBP) targets: ≤180 mmHg, <160 mmHg, and <140 mmHg (40 patients in each group). Treatment will begin soon after the blood clot causing the stroke is removed, using anti-hypertensive medication given intravenously with a goal to lower and maintain the SBP below assigned target for 24 hrs.

The scientists will assess the safety of lower BP targets (<160 mmHg and <140 mmHg) by quantifying the volume of stroke measured with an MRI scan obtained at 36+/-12 hours and participants' functional status at 90 days measured with a patient centered disability score. Participants will undergo the 36 +/-12-hour MRI scan as part of their routine clinical care and will not be asked to prolong their hospital stay for study purpose. A phone interview will take place to determine their functional status at 90-days.

Enrollment of 120 patients will provide 80% power to detect a 10 cubic centimeter increase in stroke volume and a 0.10 decrease in utility-weighted modified Rankin score (a patient-centered disability score) for every 20 mmHg decrease in SBP. An interim analysis will be conducted after enrollment of 60 patients at which time the study may stop for safety concerns.