Impact of stroke co-morbidities on cortical collateral flow following ischaemic stroke

Abstract

Acute hyperglycaemia and chronic hypertension worsen stroke outcome but their impact on collateral perfusion, a determinant of penumbral life span, is poorly understood. Laser-speckle contrast imaging (LSCI) was used to determine the influence of these stroke comorbidities on cortical perfusion after permanent middle cerebral artery occlusion (pMCAO) in spontaneously hypertensive stroke prone rats (SHRSP) and normotensive Wistar rats. Four independent studies were conducted. In animals without pMCAO, cortical perfusion remained stable over 180 min. Following pMCAO, cortical perfusion was markedly reduced at 30 min then gradually increased, via cortical collaterals, over the subsequent 3.5 h. In the contralateral non-ischaemic hemisphere, perfusion did not change over time. Acute hyperglycaemia (in normotensive Wistar) and chronic hypertension (SHRSP) attenuated the restoration of cortical perfusion after pMCAO. Inhaled nitric oxide did not influence cortical perfusion in SHRSP following pMCAO. Thus, hyperglycaemia at the time of arterial occlusion or pre-existing hypertension impaired the dynamic recruitment of cortical collaterals after pMCAO. The impairment of collateral recruitment may contribute to the detrimental effects these comorbidities have on stroke outcome.

Time Course and Clinical Relevance of Neurological Deterioration After Endovascular Recanalization Therapy for Anterior Circulation Large Vessel Occlusion Stroke

“…Recanalization rates should receive more attention during EVT. If recanalization is not achieved, prevention of hypovolemia ( Arenillas et al, 2018 ), hypo- and hypertension ( Biose et al, 2020 ; Raychev et al, 2020 ), hyperglycemia ( Biose et al, 2020 ), and hyperuricemia ( Menon et al, 2013 ) are primary targets for preserving collaterals. Other uncontrollable factors, including history of hypertension, CE stroke, lower ASPECTS and high NIHSS score, should also be considered in decision-making protocols before EVT.…”

Hemodynamics of Leptomeningeal Collaterals after Large Vessel Occlusion and Blood Pressure Management with Endovascular Treatment

“…The normal physiological response of vasodilation to decreased perfusion pressure is altered in various pathological conditions such as aging, long-standing hypertension, and hyperglycemia. [19][20][21] This resulting impairment in the CA response is not an all-or-none phenomenon but rather a graded and variable response (Figure 1). 22,23…”

Role of diabetes in collateral status assessed in CT perfusion–derived dynamic CTA in anterior circulation stroke

“…There is a controversial debate regarding the influence of diabetes on collaterals in acute ischemic stroke. While results of animal studies indicate a strong association between diabetes and collateral status [3][4][5], clinical studies based on single-phase collateral assessment report to the contrary [8,9,[16][17][18]. To our knowledge, this is the first study particularly analyzing the association of diabetes with collaterals based on dynamic/multiphase collateral assessment.…”

“…It has not yet been clarified why diabetic patients tend to have poor clinical outcome. Based on animal experiments, several authors have discussed that diabetes might be associated with poor collaterals leading to poor outcome [3][4][5].…”