Paradigm Change? Cardiac Output Better Associates with Cerebral Perfusion than Blood Pressure in Ischemic Stroke

Abstract

IntroductionIn patients with acute ischemic stroke, penumbral perfusion is maintained by collateral flow and so far is maintained by normal mean arterial pressure (MAP) levels. Since MAP is dependent on cardiac function, optimization of cardiac output might be a valuable hemodynamic goal in order to optimize cerebral perfusion (CP).MethodsCerebral perfusion was assessed by transcranial color-coded duplex and transcranial perfusion sonography in 10 patients with acute large hemispheric stroke. Time-to-peak (TTP) values of defined regions of interest (ROI) within the middle cerebral artery (MCA) territory were assessed bilaterally in addition to mean flow velocities of the MCA. Via semi-invasive advanced hemodynamic monitoring systemic hemodynamic parameters were assessed, including MAP and cardiac index (CI). Patients received sonographic follow-up after optimizing CI.ResultsTTP values of the deeply located ROIs of the non-affected as well as the affected hemisphere correlated highly significantly with CI (in affected side r = −0.827, p = 0.002; and in non-affected side r = −0.908, p < 0.0001). This demonstrates dependence of CP on CI, while correlation with MAP was not detected. Neither CI nor MAP revealed significant correlation with MCA velocity.

Brain–heart interaction after acute ischemic stroke

“…Additionally, since brain damage can modify the autonomic and neurohormonal pathways involved in the control of heart function, patients affected by stroke are extremely vulnerable to severe cardiac adverse events [2]. In particular, AIS can contribute to impaired cerebral autoregulation, thus making cerebral blood flow directly dependent on cardiac function [3]. In this context, the concept of a two-way interaction between the brain and heart has been proposed [4,5].…”

Cognitive Dysfunction after Heart Disease: A Manifestation of the Heart‐Brain Axis

“…The occurrence of brain disease, including cerebrovascular diseases, degenerative diseases of the nervous system, and infectious diseases of the central nervous system, can lead to myocardial injury and even cardiac dysfunction, which is described as the brain-heart axis [ 2 – 4 ]. On the other hand, the physiological activities and processes of the brain, such as cognitive ability and language capabilities, are directly affected by cardiac function, which is described as the heart-brain axis [ 5 – 8 ]. Cardiac dysfunction due to various causes, not only existing brain disease, can lead to new brain injury [ 8 ].…”

Fluid management concepts for severe neurological illness

“…It seems evident that a blood-volume responsive measure like CO , rather than mean arterial pressure, would be superior in a situation in which avoiding secondary brain injury requires both avoiding hypoperfusion of penumbral tissue, and limiting edema related to ischemic necrosis from the primary insult. Pilot data from [32] strongly support the link between CO and cerebral perfusion, and are the basis for this group’s recently reported clinical trial design [33], the results of which we eagerly await. Conversely, the risks of volume therapy without CO guidance are suggested by a secondary analysis of the Albumin in Acute Stroke Part 2 (ALIAS 2) trial [34].…”