Blood PREssure Augmentation in Large-vessel Occlusion Stroke Study (PRESS)

Blood PREssure Augmentation in Large-vessel Occlusion Stroke Study (PRESS) - The occlusion of a large brain blood vessel leads - within minutes to hours - to the formation of an area of irreversibly damaged tissue. A larger region of hypoperfused tissue that is functionally impaired but not yet infarcted (the penumbra) surrounds this infarct core. The fate of the penumbra - and thus final infarct size - largely depends on compensatory perfusion via collateral blood vessels.

Robust animal data shows that blood pressure augmentation improves blood flow to the ischemic tissue, resulting in improved neurologic function and decreased infarct volume. In humans, the direct relationship between blood pressure and CBF can be observed in vivo using monitoring of physiological data or neuroimaging (Figure 1). Furthermore, several case reports and small studies have demonstrated improvement in cerebral blood flow and clinical deficits with induced hypertension in acute LVO stroke.

Our central hypothesis is that induced hypertension can be used as a neuroprotective strategy to "freeze" the ischemic penumbra until recanalization is reached.

PRESS is an open-label, prospective, single-center pilot trial to assess the feasibility and tolerability of short-term blood pressure augmentation to enhance collateral flow and minimize infarct progression in acute LVO stroke patients undergoing endovascular therapy (Figure 2). The trial is planned to include 40 subjects with acute LVO stroke who meet the eligibility criteria. In Stage I of the study, we will monitor beat-to-beat blood pressure and other hemodyanmic parameters in 20 patients receiving standard-of-care therapy. For the second stage, we will enroll an additional 20 patients who will receive blood pressure augmentation therapy using intravenous fluids and phenylephrine or norepinephrine infusion. The study will assess how quickly a target blood pressure can be reached in the acute stroke setting, and furthermore, the ability to successfully maintain these blood pressure targets throughout the intervention and avoid hypotension during conscious sedation or general anesthesia. The study will also evaluate recruitment feasibility and preliminary safety of blood pressure augmentation. Stage II of the study will begin after Stage I have been completed (Figure 3).